Converting and storing solar energy directly as chemical energy through photoelectrochemical devices are promising strategies to replace fossil fuels. Metal oxides are commonly used as photoanode materials, but they still encounter challenges such as limited light absorption, inefficient charge separation, sluggish surface reactions, and insufficient stability. The regulation of surface oxygen species on metal oxide photoanodes has emerged as a critical strategy to modulate molecular and charge dynamics at the reaction interface. However, the precise role of surface oxygen species in metal oxide photoanodes remains ambiguous. The review focuses on elucidating the formation and regulation mechanisms of various surface oxygen species in metal oxides, their advantages and disadvantages in photoelectrochemical reactions, and the characterization methods employed to investigate them. Additionally, the article discusses emerging opportunities and potential hurdles in the regulation of surface oxygen species. By shedding light on the significance of surface oxygen species, this review aims to advance our understanding of their impact on metal oxide photoanodes, paving the way for the design of more efficient and stable photoelectrochemical devices. The increasing demand for sustainable and clean energy has led to an intense focus on the development of efficient solar energy conversion systems . The useIn PECs, the electron–hole pairs produced by the photoelectrode undergo reduction and oxidation reactions at the cathode and anode, respectively. In the actual photoelectrochemical production of sustainable fuels and chemicals, whether it is hydrogen production from water or the reduction of carbon dioxide or nitrogen, consuming electrons and protons at the photocathode needs to be matched with the photoanode to drive water oxidation or other substrates’ oxidation . This ne4, TiO2, Fe2O3, and WO3, have emerged as promising materials for photoanodes due to their unique electronic structure properties, good stability, and abundance [Metal oxides, such as BiVObundance . Despitebundance . In recebundance , crystalbundance , ion dopbundance ,13, defebundance , and corbundance . HoweverTo enhance the efficiency of photoelectrochemical systems, a thorough understanding and precise control of the surface properties of metal oxide photoanodes are crucial. Among the various factors influencing the photoelectrocatalytic performance of these photoanodes, surface oxygen species play a particularly significant role. These surface oxygen species can profoundly impact the reactivity, stability, and photoelectrochemical properties of metal oxide photoanodes. Specifically, surface oxygen vacancies, which are oxygen-related surface structures that influence the surrounding metal coordination environment, have been extensively studied as crucial reaction sites. Therefore, in this article, we acknowledge surface oxygen vacancies as a distinct and noteworthy type of surface oxygen species.Additionally, we focus on exploring oxygenated species present on the surface of metal oxides as another important category of surface oxygen species. In this section, we provide a detailed overview of surface oxygen vacancies and oxygenated species in metal oxide photoanodes. Specifically, we discuss the classification of these surface oxygen species and delve into their respective generation mechanisms. Furthermore, we examine the advantages and disadvantages associated with their presence in photoelectrocatalytic processes.Vacancies are inherent in metal oxides and can be categorized into metal vacancies and oxygen vacancies based on the type of missing ions. Surface oxygen vacancies specifically pertain to defects occurring within the lattice of oxygen atoms on the surface of metal oxides. The formation of surface oxygen vacancies primarily stems from the behavior of oxygen atoms within the solid structure. Two mechanisms commonly contribute to the generation of vacancies on the solid surface: 1. Differences in lattice structure, morphology, or composition of the material surface from the bulk can lead to a scarcity of oxygen atoms on the surface . 2. The The introduction of surface oxygen vacancies induces changes in the electronic structure and band gap of metal oxides. By regulating surface oxygen vacancies, it is possible to adjust charge transport at the interface and increase the participation of holes in surface reactions . MoreoveHowever, it is important to consider the disadvantages associated with surface oxygen vacancies. A high concentration of oxygen vacancies can create intermediate energy gap states within the photoanode, resulting in a more pronounced recombination and reduced photocatalytic activity . FurtherTo enhance the efficiency of the photoanode’s reaction, it is imperative to gain a clearer understanding of the role of surface oxygen vacancies in photoelectrochemistry. By carefully analyzing the structure–activity relationship between surface vacancies and activity, we can provide refined guidelines and design strategies for the regulation of oxygen vacancies. In this section, we primarily discuss the construction strategies for surface oxygen vacancies in metal oxides and their role in photoelectrocatalysis.2 is often used as the reducing atmosphere. For example, Li achieved non-stoichiometric WO3-X by calcining a tungsten oxide photoanode in an H2/Ar atmosphere [3-X photoanode, with an optimal amount of oxygen vacancies and calcined at 350 °C, exhibited a ten-fold increase in photocurrent density compared to WO3, along with excellent catalytic stability. It has been observed that non-stoichiometric WO3-x obtained through hydrogen treatment is resistant to reoxidation and can prevent the dissolution of peroxy species induced by oxidation.Heat treatment is a commonly employed method to introduce oxygen defects in metal oxides. It involves subjecting metal oxides to elevated temperatures in a reducing gas atmosphere, where reducing gases react with the metal oxides, resulting in the removal of some lattice oxygen atoms and the introduction of oxygen defects. Hmosphere . The con3 has a large number of oxygen vacancies both on the surface and in the bulk, but only the surface oxygen vacancies acted as charge recombination centers [3  surface (5.483 Å). This allowed ethylene glycol to form stable bifurcated hydrogen bonds with O-H groups, with a distance of approximately 2.5 Å  to treat a WOcarriers . This en4 solution. When a BiVO4 photoanode is immersed in NaBH4 solution, the Bi-O bonds on its surface break, leading to the removal of oxygen atoms and the formation of oxygen vacancies [4 photoanodes, optimizing the performance of the photoanode [4 solution, or hypophosphorous acid, researchers can achieve the desired defect structures in metal oxide photoanodes, leading to enhanced charge transfer, improved conductivity, and better catalytic performance.Another commonly used reduction reagent is NaBHacancies . Furtherotoanode . These aRHE in a potassium borate solution to reduce BiVO4 for 150 s [3+ and V5+ ions in BiVO4, resulting in the generation of oxygen vacancies. They found that the introduction of oxygen vacancies enhanced the separation efficiency between the bulk phase and the surface of BiVO4, thereby improving its water oxidation performance. This electrochemical reduction method was also applied to TiO2 photoanodes [In addition to the methods mentioned earlier, electrochemical reduction offers a milder and more environmentally friendly approach to generate oxygen vacancies in metal oxide photoanodes . For exaor 150 s . This prtoanodes .4 by exposing it to light for 20 h under an open-circuit voltage in a potassium borate electrolyte [4 at 1.23 VRHE from 1.0 mA cm−2 to 4.3 mA cm−2  on the behavior of oxide semiconductors, particularly in terms of Fermi level de-pinning and enhanced hole migration  on the TiO species . Similar halides . Oxygen acancies .4 has been found to enhance the adsorption of OHads, Oads, and OOHads species involved in the water splitting process, thereby promoting the surface catalytic activity [4 photoanode. This surface modification facilitates the adsorption of water molecules, thereby improving the charge transfer during oxygen evolution reactions [2O3 photoanodes has been shown to improve both their water oxidation activity and stability. These vacancies reduce the width of the depletion layer, while also enhancing the hydrophilicity of α-Fe2O3. As a result, the water oxidation kinetics on α-Fe2O3 photoanodes are significantly improved [The presence of surface oxygen vacancies in W-doped BiVOactivity . Liu et eactions . Furtherimproved .3 photoanode tends to follow a four-electron pathway, leading to suppression of peroxygen species generation. This contributes to a higher Faradaic efficiency in oxygen production and improved stability of oxygen-deficient WO3 photoanodes [2-treated surface-oxygen-vacancy-enriched BiVO4 photoanode, which tunes the surface wettability of BiVO4 toward a kinetically controlled H2O2 production process. This modification enhances the charge separation efficiency, resulting in a significantly higher Faradaic efficiency (FE) (81.2%) compared to BiVO4 photoanodes. At 1.6 VRHE, the H2O2 concentration could accumulate to 4.58 × 10−4 M within 2 h, corresponding to a production rate of 11.45 μmol h−1. This work highlights the importance of the microenvironment at the surface of photoanodes in mediating competing reactions in aqueous solutions [4 (001) surface with subsurface vacancies is most suitable for the oxygen evolution reaction, while the pristine (011) surface is more favorable for the production of H2O2 [The presence of surface oxygen vacancies can also affect product selectivity by regulating the reaction pathway. The water oxidation on the oxygen-vacancy-rich WOtoanodes . Park etolutions . Theoret of H2O2 .The surface of a photoanode is covered with a large number of adsorbed oxygenated species, some existing before the reaction occurs and some generated during the reaction. Common oxygenated species on metal oxide photoanodes include adsorbed water molecules, adsorbed hydroxyl groups, adsorbed oxygen, peroxygenic species, and oxyanion species. The configuration and composition of oxygen-containing species on the surface of metal oxides are influenced by factors such as the nature of the metal oxide, the preparation method employed, and the reaction conditions. For example, the adsorption properties of water on metal oxides vary due to the inherent differences in the nature of different materials. The surface exposure of the same metal oxide due to different preparation methods also affects the coverage of surface hydroxyl groups. The type and content of oxygen-containing species on the surface of metal oxides can be changed by introducing defects or coating co-catalysts. During the photoelectrocatalytic process, metal oxide photoanodes are usually exposed to electrolytes with water as the solvent. Oxygen-containing species such as water molecules adsorbed on the surface can generate new oxygen-containing species under light or high potential. For example, the adsorbed hydroxyl groups are transformed into hydroxyl radicals with strong oxidizing ability under light irradiation, and the oxoacid anions on the surface of metal oxide photoanodes may be transformed into corresponding anion radicals. These oxygenated species on the surface of metal oxides are crucial for oxidation reactions, especially when the selectivity of oxidation products needs to be controlled.Oxygenated species on the surface of metal oxide photoanodes affect multiple aspects of the photoelectrochemical process. For example, surface oxygenated species introduce new energy levels at the metal oxide surface, which can act as electron donors or acceptors, thereby influencing the band bending of the material and the overall charge separation process. Furthermore, the adsorbed oxygenated species on the surface of metal oxides have a direct impact on the adsorption and activation processes of reactants at the photoanode surface. Therefore, understanding the classification, generation mechanisms, and roles of these adsorbed oxygenated species is crucial for comprehending their influence on photoelectrocatalytic processes.In the following section, we delve into the classification of adsorbed oxygenated species on metal oxide surfaces, explore their mechanisms of generation, and elucidate their significance in photoelectrocatalytic reactions.2O3 has abundant adsorbed hydroxyl groups after solvothermal treatment in methanol, which increases its hydrophilicity and enhances its water oxidation activity [2O3/Fe2TiO5 heterostructure. The HEDP-covering layer can be used as a hole storage layer by promoting charge transfer and improving the oxidation kinetics of water [4 photoanode surface with nitrogen doping introducing oxygen vacancies (N–OVac–BiVO4) becomes less hydrophilic, which promotes the generation of hydrogen peroxide and inhibits the decomposition of hydrogen peroxide [Vac–BiVO4 photoanode can realize the selective oxidation of water to hydrogen peroxide  [2, thus contributing to the enhancement of PEC performance. Similarly, it was also found that fully immersing the TiO2 photoanode in the NaBH4 solution also generates TiIIIO(OH) surface states to promote electron transfer, thereby improving the catalytic activity [2 by NaBH4 becomes challenging when the TiO2 photoanode is only partially submerged in the NaBH4 solution. Other studies have shown that hydroxyl groups can polarize the surface of TiO2, leading to the creation of a substantial electric field within the surface region. This phenomenon results in the elevation of the energy band edge, thus promoting the separation and migration of photogenerated charges, thereby improving the efficiency of water oxidation [2O3 photoanode can also act as active sites to mediate the water oxidation reaction [2O3 also contribute to charge recombination, thereby diminishing its ability to separate charges effectively [The hydroxyl groups on the surface of metal oxides are typically produced by the reaction of water or alcohol molecules on the surface. The hydroxyl species act as a bridge between the metal oxide surface and the solution, affecting the reactivity of the surface. They can also act as electron acceptors or recombination centers to affect the charge transfer at the interface. For example, Zhu et al. found that the electrochemical reduction treatment of TiOIIIO(OH) . Photoelactivity  were coated on oxygen-vacancy-rich BiVO4 using caffeic acid as a bridging agent. This transfer of oxygen evolution sites from the oxygen vacancy of BiVO4 to NiFe-MOFs enhances the activity and stability of the photoanode.Furthermore, studies also demonstrate that adsorbed oxygen also affects the charge separation performance of the photoanode . For exa3 photoanodes produced hydrogen peroxide under acidic conditions and believed that peroxide species would passivate the catalyst surface, resulting in a decrease in the activity of WO3. Therefore, when WO3 exhibits a high selectivity for oxygen evolution reaction, its stability is also enhanced [2O3 photoanodes are identified as low-energy surface states, which can cause Fermi level pinning and inhibited charge separation performance. We found that the coating of conductive MOF on Fe2O3 enhanced the high-energy surface state of Fe=O species, thereby enhancing water oxidation activity [4 by SnO2-x promotes the generation of H2O2, while inhibiting the competitive OER process [The oxidation process of water involves the formation of O–O bonds, resulting in the inevitable formation of peroxide species on the surface of metal oxides. These peroxides are undesirable during the oxygen evolution reaction, while in certain cases, hydrogen peroxide is a desired product. However, controlling water oxidation pathways is challenging. Sometimes, these peroxide species not only lead to surface passivation but also introduce recombination centers, reducing the charge separation efficiency and overall photoanode activity. Nonetheless, they can also act as active oxygen species to drive specific selective oxidation reactions. Therefore, it is crucial to investigate the formation mechanism of peroxide species on metal oxide photoanode surfaces. In earlier studies, researchers found that WOenhanced . The peractivity   scan tests, when combined with photoelectrochemical impedance spectroscopy data, provide valuable information on the presence of surface states. For example, Chen et al. studied the surface state of bismuth vanadate, and they found that during the photocatalytic water oxidation process, a large number of photogenerated electrons participated in the surface reduction process of VObination . This restigated . They hyThe combination of CV scan tests provides valuable insights into the charging and discharging behavior of surface oxygenated species, their participation in redox reactions, and their impact on the photoanode’s performance and reactivity.2O3 photoanode and observed that the impedance value initially decreased and then increased as the potential increased [2O3 photoanode  is a computational method that can be used to calculate the formation energy of oxygen vacancies on the surface of metal oxides and the adsorption energy of oxygen-containing species. By analyzing these energies, DFT can provide insights into the difficulty of vacancy formation and the effects of oxygen species on charge separation and surface reactions. For example, researchers have used DFT to calculate the adsorption energy of hydroxyl (OH) on different crystal planes and grain boundaries of tungsten oxide, such as the (200) and (002) planes. The results indicated that the adsorption energy of OH at grain boundaries is weaker, suggesting that hydroxyl radicals are more likely to form in these regions  Figure a. CalculIn summary, the development of efficient and stable photoanodes is crucial for solar energy conversion. These photoanodes should possess a high oxidation reaction activity, excellent charge separation performance and long-term stability, and high selectivity for specific oxidation reactions. However, current research has yet to produce a photoanode that simultaneously achieves high efficiency, selectivity, and stability. Metal oxides, as a promising class of photoanode materials, offer the ability to adjust surface oxygen species, their concentration, and spatial distribution. Modulating these surface properties holds potential for enhancing the performance of photoanodes in terms of activity, selectivity, and stability. With the advancement of surface characterization technology, the understanding of the surface of metal oxides has been deepened. It has been found that the composition and properties of metal oxide surfaces play a key role in the charge separation and reaction of photoanodes. The metal oxide surface not only affects the driving force of hole transfer from the bulk to the surface, and through the interface, but also influences the reaction path and efficiency of the substrate, and the long-term stability of the photoanode. As research in photoelectrochemical (PEC) oxidation extends beyond water oxidation to other oxidation reactions, the development of photoanodes suitable for different oxidation reactions becomes increasingly important. This necessitates a clear understanding of the relationship between surface properties of the photoanode and the specific oxidation reaction. Oxygen vacancies and oxygenated species on the surface of metal oxides are critical surface species that serve as oxidation reaction sites and participate in the transfer of oxygen during the oxidation process of substrates. However, the specific roles of surface oxygen species in oxidation reactions with different substrates are still not fully understood. Therefore, deeper insights into these surface species through advanced surface characterization techniques are necessary to clarify their functions and roles in different oxidation reactions.(1)Regulation and evolution: The regulation of surface oxygen vacancies and oxygen-containing species often relies on post-processing strategies involving specific atmospheres or solvents, coupled with external stimuli such as heat, electricity, or light. However, the underlying mechanisms governing surface changes during the regulation process remain unclear, and achieving precise control over the spatial distribution and concentration of these surface species remains challenging. Therefore, a deeper understanding of the regulation principles is needed, along with the development of simpler methods to achieve specific control, such as selectively introducing oxygen vacancies and oxygen-containing species on specific exposed crystal faces. Additionally, the stability and differences of surface oxygen vacancies and oxygen species generated by different regulation strategies are rarely investigated. Attention should also be directed toward their evolution during the reaction process, as this may impact their long-term activity. Protection strategies for preserving surface oxygen vacancies and oxygen species should be explored, along with efforts to achieve interface dynamic equilibrium or faster recovery strategies. The dynamic study of surface oxygen vacancies and oxygen species will provide insights into their specific roles in photoelectrocatalytic processes. The evolution study of surface oxygen species will also clarify their specific roles in the photoelectrocatalytic process.(2)Carrier separation: Surface oxygen species can be either favorable or unfavorable for carrier separation. They can act as charge recombination centers, accelerating charge recombination, or serve as electron donors, leading to Fermi level pinning and inhibiting hole migration, among other undesirable effects. Conversely, they can function as electron or hole capture acceptors, enhancing carrier lifetime and facilitating hole migration. Exploring the fundamental aspects of charge transport and providing a more comprehensive explanation for how surface structure influences electron and vacancy behavior are necessary. For instance, the role of polarons in charge transport and how the introduction of surface oxygen species affects them should be investigated. Furthermore, the influence of surface oxygen species on other material properties should be considered to avoid drawing erroneous conclusions regarding the relationship between catalyst surface structure and charge separation.(3)Control of product selectivity: The selectivity of oxidation reaction products is affected by various factors, including the adsorption configuration or strength of the substrate on the surface, as well as the energy barriers of different steps in the oxidation process such as dehydrogenation or hydration. Therefore, as the understanding of substrate oxidation reaction mechanisms advances, the role of surface oxygen species in this context should be further explored. Additionally, a clearer understanding of how oxygen species on metal oxide surfaces affect reaction intermediates and products is necessary. Attention should also be given to the influence of different oxygen-containing species on competing oxidation reactions and whether different reaction pathways share common oxygen-containing intermediates. When studying the effect of surface oxygen species on product selectivity, the effect of different metal atoms should be further explored, considering the synergy between single atoms or clusters and surface oxygen species.(4)For research methods and characterization strategies: To investigate the specific role of surface oxygen vacancies and oxygen-containing species in photocatalytic processes, the development of more comprehensive research methods is essential. These methods should aim to explore their influence on the behavior of molecules and charges. For example, experimental designs can be employed to examine the adsorption performance of surface oxygen species on different substrates or to investigate the adsorption strength of specific functional groups on the catalyst surface. As surface characterization technology advances, finer analyses of surface compositions may become possible. However, the detection of intermediate species for different metal oxides under varying electrolyte or substrate conditions is still lacking. Therefore, it is crucial to employ in situ characterization techniques to detect oxidation reaction intermediates under relevant conditions.


ATP and Kir2.1 channels as primary sensors. Finally, we present major unresolved questions and outline how they can be addressed.Pericytes, attached to the surface of capillaries, play an important role in regulating local blood flow. Using optogenetic tools and genetically encoded reporters in conjunction with confocal and multiphoton imaging techniques, the 3D structure, anatomical organization, and physiology of pericytes have recently been the subject of detailed examination. This work has revealed novel functions of pericytes and morphological features such as tunneling nanotubes in brain and tunneling microtubes in heart. Here, we discuss the state of our current understanding of the roles of pericytes in blood flow control in brain and heart, where functions may differ due to the distinct spatiotemporal metabolic requirements of these tissues. We also outline the novel concept of electro-metabolic signaling, a universal mechanistic framework that links tissue metabolic state with blood flow regulation by pericytes and vascular smooth muscle cells, with capillary K In the 2) and nutrients. Cardiac cells beat continuously, with their pace—and therefore energy requirements—modulated by external factors such as sympathetic:parasympathetic balance, hormone levels, and overwhelmingly the degree of whole-animal activity (+]), which fluctuates according to neuronal activity  ATPase and the plasma membrane calcium (Ca2+) ATPase, which reverse the ionic fluxes that occur during action potentials and synaptic activity  have evolved to guarantee a continuous and extremely efficient supply of energy to support moment-to-moment heart work for an entire lifetime. Here too, it is now emerging that pericytes are intimately involved in these processes. Coronary blood flow varies with time depending on aortic pressure, myocardial extravascular pressure, and resistance to flow, which, in turn, are critically dependent on myocardial metabolism and neural and hormonal controls  difference in heart is nearly always maximal, and the ratio of arterial pO2 to venous pO2 is maintained at around 1.6 to 1.7 unless the arterial pO2 falls to under 60% of its normal level  Arteries and arterioles secrete elastin (b) Arteries and arterioles are suitably wide to allow the passage of red blood cells (RBCs) side by side, whereas capillaries are narrow enough to allow only for single-file RBC transit  Art transit . Accordi transit . In the  transit , 41–43  to regulate tone (3) receptor–mediated intracellular Ca2+ signaling appears to play a prominent role in the contraction of these cells  and PDGFRβ (Pdgfrb) alone are two markers that can be used to at least initially identify cardiac pericytes and reveal their physical structures and locations  and the ATP-sensitive K+ (KATP) channel subunits Kcnj8 (Kir6.1) and Abcc9 (SUR2), which can be used as markers and also suggest important functional contributions of these proteins  and Tagln (transgelin), but to a much lower degree than upstream SMCs and contractile pericytes , which typically is around −100 mV under resting conditions in brain   . While tx (K (2) .2+ channels, which causes a fall in cytosolic Ca2+, interrupting the Ca2+-dependent process of actin-myosin crossbridge cycling  and are passed via gap junctions from cell to cell to arrive upstream at the level of the arteriole . En rout cycling . This re cycling .Several studies have noted the presence of peg-socket junctions formed between pericyte processes and cell bodies and underlying cECs , 105, whThe recent intensive focus on brain pericyte function has allowed us to make rapid progress in our understanding of the intricate cellular interactions that control blood flow in this vascular bed, and this likely offers clues to understand pericyte contributions to blood flow control in other organs, including heart.+ that appears to relax not only upstream SMCs but also these transitional zone contractile pericytes , a gaseous signaling molecule that rapidly diffuses to and relaxes overlying contractile pericytes. The Ca2+ events that precede NO generation are intimately dependent on capillary electrical signaling, which hyperpolarizes the membrane to increase the driving force for Ca2+ entry into ECs   .ATP channels couple changes in intracellular metabolism to electrical activity in the cell membrane. Thus, we reasoned that the high expression of KATP channels in thin-strand pericytes may position these cells as metabolic sentinels of the brain and that they may respond to local metabolic disturbances by generating hyperpolarization that can then be passed into the endothelium via peg-socket gap junctions to tune electrical signaling throughout the underlying capillary bed and shape blood flow  ions, forming MgADP, bind to a site on the auxiliary sulfonylurea subunit to induce channel opening   , 126 may in vivo , 128. ThATP channel–dependent and EC Kir channel–dependent electrical signal that propagates to upstream arterioles and drives profound dilation to elicit an increase in blood flow to the underlying capillaries   whether this is the direct result of changes in pericyte ADP:ATP ratio and (b) whether a more subtle contribution from EC KATP channels can be detected.Strikingly, we discovered that manipulation of energy substrate supply to pericytes evokes a pericyte Killaries , 21. Speillaries –134] leahannels) . These dhannels) . Accordihannels)  and astrhannels) , 137 to channels , which cncreases . These dATP channel activation may also promote GLUT1 translocation to the membrane  could also potentially promote high-capacity glucose import by relieving ATP inhibition of GLUT1. Further experiments are needed to examine these possibilities.Intriguingly, Kmembrane . The mol and ADP –141 and,ATP channel , which further hyperpolarizes cECs, increasing blood flow to provide the needed O2 and nutrients that are critical for ongoing healthy tissue function.Together, these collected findings represent state-of-the-art information on how brain and heart tissues use known and emerging features of the microcirculation and characteristics of small vessel elements to regulate blood flow through metabolic control. At the small vessel level, several mechanisms use metabolic cues and measures to provide a local signal to regulate flow. EMS, the umbrella term for these mechanisms, uses metabolic sensors to generate signals to increase blood flow in response to metabolic needs. As ventricular myocytes or brain pericytes consume ATP, cytosolic [ATP] declines and cytosolic [ADP] rises. Together, these concentration changes activate KNOTCH3 gene, which pericytes heavily express, and the ensuing damage to pericytes is a key pathogenic feature of the disease  contribute to the control of pericyte contractile state? Given the expression of several voltage-dependent K+ and Ca2+ genes in pericytes  through the sensitivity of the Ka) Optogenetic tools are needed to depolarize or hyperpolarize specific cells in the signaling chain between metabolically active elements  and the cells that directly control blood flow. Thus, an exciting target includes the cECs in addition to pericytes themselves. (b) Fluorescence signaling reporters expressed in cells that regulate blood flow will be remarkably helpful. Thus, GCaMP8  should be expressed as a transgene in pericytes or SMCs to indicate how contractile cells respond to an initiating electrical signal. Moreover, use of modern, easy to implement, genetically encoded voltage sensors in the vasculature would enable the study of signal propagation throughout the vasculature with unprecedented detail. (c) Fluorescence lifetime reporters expressed in transgenic form to measure [ATP] in a targeted cell would also be exceedingly useful. Surmounting this technical challenge will enable us to answer questions related to energy balance that span many fields. (d) Multiphoton imaging is already being extensively used in brain to carry out such fluorescence experiments in living animals through long-term cranial windows. Although investigations in brain are ahead of those in heart because of the difficulty in carrying out such experiments in moving tissue, progress is being made in both areas, and the prospects are great for further important advances in both tissues.The investigations spawned by recent exciting findings related to pericyte biology and the control of blood flow centered in heart and brain enable new hypotheses and detailed studies of the mechanisms of blood flow regulation in small vessels. This work seeks to address the key questions outlined above and will be greatly advanced through full exploitation of at least the following four technical methods. (Supplementary Boxes 1-3


Multiple myeloma (MM) is a hematological malignancy characterized by the dysregulated proliferation of transformed plasma cells (PCs) primarily in the bone marrow (BM) . For themilieu interplay in mediating resistance to PIs  and IMiDs (Chen and Gooding). While providing a detailed summary of the current knowledge on the interaction between MM cells and BM components, Schwestermann et al. have focused on how the metabolic rewire shapes MM cell ability to adapt, grow and resist to therapies, specifically PIs. Importantly, they highlight how metabolic switches occurring after treatment with PIs may be targeted to overcome PI-resistance and improve overall drug efficacy. On a similar line, Chen and Gooding summarize the current literature on the mechanisms underlying IMiDs resistance with a specific highlight at the gap existing in the characterization of Cereblon (CRBN)-independent mechanisms, including those related to immune microenvironment and metabolism. In a broader light, Solimando et al. provide an extensive overview on the mechanisms by which MM resist to different therapies, including epigenetic modification and cancer cell stemness; and discuss therapeutic strategies to improve the management of MM patients.Specifically, two reviews discuss the role of the MM-Raimondi et al. discuss the importance of metabolic reprogramming of MM cells in the context of MM-related bone disease. Specifically, they focus on the role of glutamine addiction, in controlling osteoblast differentiation from mesenchymal stromal cells, and thus bone remodeling. While providing an exhaustive review of the implication of metabolic features in the pathophysiology of MM bone disease, they also emphasize the clinical implication of such findings that may allow for the identification of new tracers of active bone disease that are under investigation that may be more sensitive in patients with negativity at the PET/TC with 18F-fluorodeoxyglucose (FDG).Of clinical relevance, Trudu et al. in this Research Topic, describes a novel intrinsic role of arginine shortage in directly promoting MM proliferation and resistance to therapies. The authors show that, beyond the established immunosuppressive role of arginine deprivation on T cells , or in particular by focusing on the MM tumor suppressor TRAF3  a signal transducer that has been recently showed to be recruited to the mitochondria in B cells (Nair et al. extensively analyze how mitochondria metabolism influences MM development and drug resistance and vice versa how MM mutations affect metabolic pathways. The authors also discuss the role of mitochondria in regulating MM metabolism, redox homeostasis, iron and calcium fluxes, and the activation of the integrated stress response and intrinsic apoptosis. On this line, Jung et al., describe the role of TRAF3 in normal and malignant B cells. TRAF3 is a negative regulator of key B cell signaling pathways, whose loss induces enhanced antibody responses and increased B cell survival (Growing evidence are showing that mitochondria are critical for MM development, progression, and sensitivity to therapies. Two reviews in this Research Topic analyzed the role of mitochondrial metabolism in general in MM pathobiology ( B cells . Nair etsurvival , 21. Morsurvival . In theiFairfield et al. The authors propose three in vitro culture systems allowing the study of MM-adipocyte crosstalk using primary BM adipocyte and not those obtained through the differentiation in vitro of BM-derived mesenchymal stromal cells. Of technological relevance, the authors describe in detail the protocols to perform 2D and 3D co-cultures and the following imaging and proteomic characterizations, providing novel tools to dissect how adipocytes and MM cells influence each other in the BM environment.Finally, novel original culture methods for the analysis of the interplay between BM adipocyte-MM cells have been presented by In summary, this Research Topic provides a critical overview and novel evidence on the role of proteomic and metabolic reprogramming of myeloma cells as key drivers of MM pathogenesis and drug resistance with important therapeutic implications. Open questions remain on how protein degradative and metabolic pathways affect immune activation and tumor sensitivity to immunotherapies. Further investigations will be instrumental in exploiting such metabolic and proteomic dependencies to improve the therapeutic efficacy of anti-MM agents, increase response durability and patient overall outcome.EM: Writing – original draft, Writing – review & editing, AG: Writing – original draft, Writing – review & editing.


CLEC11A (neighboring SHANK1) where DNAm and gene expression were significantly and negatively correlated, independently from genotype effects. As reported in previous studies, we confirmed the involvement of immune functions in the pathophysiology of ASD. Notwithstanding the complexity of the disorder, suitable biomarkers such as CLEC11A and its neighbor SHANK1 can be discovered using integrative analyses even with peripheral tissues.While the genetics of autism spectrum disorders (ASD) has been intensively studied, resulting in the identification of over 100 putative risk genes, the epigenetics of ASD has received less attention, and results have been inconsistent across studies. We aimed to investigate the contribution of DNA methylation (DNAm) to the risk of ASD and identify candidate biomarkers arising from the interaction of epigenetic mechanisms with genotype, gene expression, and cellular proportions. We performed DNAm differential analysis using whole blood samples from 75 discordant sibling pairs of the Italian Autism Network collection and estimated their cellular composition. We studied the correlation between DNAm and gene expression accounting for the potential effects of different genotypes on DNAm. We showed that the proportion of NK cells was significantly reduced in ASD siblings suggesting an imbalance in their immune system. We identified differentially methylated regions (DMRs) involved in neurogenesis and synaptic organization. Among candidate loci for ASD, we detected a DMR mapping to  Autism spectrum disorders (ASD) are diagnosed in children at a young age if they exhibit difficulties in social interaction and communication and have restricted interests and repetitive behaviors , 2. AffeBCL-2 and RORA) in the autistic brain, validating their methylation status of BCL-2 and RORA in lymphoblastoid cells of discordant monozygotic ASD twins and unaffected siblings  to check for spurious estimated P-values.To address the interactions between neighboring CpG sites and the net effect that these sites have on associated gene(s), we determined the methylation status of clusters of probes by running the DMRcate algorithm  built inTo assess the accuracy of the identified DMRs to classify ASD subjects, we first built a classifier model based on a Random Forest (RF) algorithm using the R package randomForest  and fed P-values for the different numbers of CpGs between genes  using bioinformatic tools that were developed explicitly for either DMPs or DMRs and that allowed us to correct gene sets ber bias ).P-values and, thus, to use the entire list of CpG-associated genes for each gene set to determine which biological functions were significantly influenced by differential DNAm between ASD and non-ASD subjects. Gene sets and the corresponding biological functions were extracted from widely used databases  and also from specialized databases which were composed of genes implicated in psychiatric disorders , genes l et al. ) and finl et al. ).For DMRs, we used an empirical Bayes GSEA method implemented in ChAMP  that hasP-values for detecting probe-gene pairs that may be potentially associated with ASD diagnosis.To examine the potential effects that differential DNAm may have on transcription activity and gene regulation, we integrated the DNAm profile with gene expression data from the same set of samples  using thcis-expression quantitative trait loci (eQTL) [cis-eQTL of the gene which was significantly associated with the differentially methylated distal probe. Then, we checked if such a genetic variant was also a mQTL. If a given SNP was a mQTL and corresponded to our distal probe, we estimated its effect on DNAm using a beta regression model [The correlation between DNAm and gene expression may also depend on genetic components. To understand potential genetic effects on DNAm and gene expression, we used the genotype data of our subjects and integrated them with published data of independent DNAm quantitative trait locus (mQTL)  and of ci (eQTL) . First, on model  where thon model .We obtained data from the Image-CpG database  to assesP-value < 0.001)  with the proportions that were calculated in the previous study where it was used an RNA-based deconvolution algorithm  Fig. . These dWe examined EPIC methylation arrays of 76 discordant autistic sibling pairs to understand the role of epigenetics in ASD. We identified two outlier families using a multidimensional scaling plot based on DNAm Beta-values . However, we found a strong correlation  between male and female coefficients estimated by sex-stratified DMP analysis, see Supplementary Fig For the differential methylation analysis between ASD and non-ASD siblings, we used the adjusted Beta-values and we identified 37,643 DMPs across the genome with a BH corrected ile TBX1 , SHANK2  [SHANK2 , and TTC2 [TTC23  .We performed GSEA to understand which biological processes may have been altered by differential methylation between ASD and non-ASD subjects. We extracted biological processes from a total of seven databases , we showed that identified DMPs were associated with biological processes related to synapse functions and neurogenesis. Although neurodevelopmental pathways are preferably studied using brain tissues, our results support the potential for identifying epigenetic biomarkers of neurodevelopment even in peripheral tissues , 48.CLEC11A. We then combined genotype data from the same samples and methylation eQTL data and showed that the correlation was not driven by genotype effects of candidate SNPs located in the same region.Differences in cellular composition, DNAm, and function of neurodevelopmental pathways are expected to be associated with differences in gene expression between affected subjects and controls. Ultimately, the association between multiple mechanisms may strongly depend on genetic variants that, for example, are responsible for differential DNAm and the regulation of gene activity . We inteCLEC11A has been identified as a candidate locus for the etiology of neurodevelopmental disorders due to its position nearby SHANK1, a gene strongly associated with ASD [SHANK1, SHANK2, and SHANK3) have been reported to disrupt neuronal activity [CLEC11A and SHANK1 in males with ASD [SHANK1 and SHANK3 [SHANK1 nor SHANK3 because these biomarkers are absent in the blood, but we did find a DMR associated with the SHANK2 gene which is instead also expressed in the blood [In other studies, the region of with ASD . SHANK factivity , 114. Diwith ASD , 116. Ind SHANK3 , 118. Wehe blood , showingCLEC11A-SHANK1 region. When validated, the methylation markers might become a valuable asset to support early diagnosis, particularly for non-syndromic or “idiopathic autism”, and assist the identification of epigenetically distinct subtypes of autism [Compared to studies based on brain tissues, our analysis using whole blood samples was limited in its power to capture neurodevelopmental genes and pathways, as we could only examine those that were not exclusively regulated in the brain. Still, we found differentially methylated sites in the blood that were associated with genes involved in neurodevelopment and ASD. We are aware that for some of these candidate genes differential DNAm may reflect a correlation between ASD diagnosis and some other variables that were not measured in our study, and may be transient, thus further investigations would be required to validate our findings. Nevertheless, our results provide further support for the possibility of using peripheral tissues to identify candidate epigenetic ASD biomarkers through integrative analyses across genomic data, as in the case of the f autism , 120, thSupplementary InformationSupplementary File 1Supplementary File 2Supplementary File 3Supplementary File 4Supplementary File 5Supplementary File 6


Promising results are expected from several ongoing clinical trials targeting new pathways involved in the pathophysiology of PAH. Pulmonary arterial hypertension (PAH) is an obstructive pulmonary vasculopathy that leads to increased pulmonary vascular resistance, right ventricular overload and failure, and to date it is still characterized by high morbidity and mortality rates . It has It is known that PAH patients’ clinical status and prognosis depend mostly on the capability of the RV to adapt to the increased afterload. In PAH, the vascular pathology causes a progressive rise in right ventricular afterload, and the right ventricle progressively increases its contractility in order to maintain its coupling to pulmonary circulation .In fact, homeometric adaptation  begins within minutes after an increase in the pulmonary arterial pressure (PAP), but when it becomes insufficient in order to support systolic function due to progression of the underlying vascular disease, the right ventricle undergoes heterometric adaptation , with consequential clinical manifestations of RV failure, leading eventually to death , 3.The mechanisms underlying the transition from hypertrophy to dilatation are not fully understood. However, the rate and magnitude of right ventricular overload, as well as the right ventricular adaptation due to genetic factors, neurohormonal activation and right ventricular ischemia supposedly play a role , 5.The ability to maintain coupling to pulmonary circulation is also influenced by the adaptive remodeling pattern of the right ventricle Fig. . An ecceDirect myocardial damage may be also responsible for a more rapid disease progression in specific PAH settings. In HIV-related PAH, inflammatory cytokines and/or viral proteins continuously released by the myocardium might cause an inflammatory damage of pulmonary vessels, characterized by intimal fibrosis and smooth muscle cell proliferation leading to plexiform vascular lesions. In support of this hypothesis is the improved survival of patients with HIV-associated PAH since the introduction of highly active antiretroviral therapy .Right heart reverse remodeling (RHRR) is considered one of the main goals for clinicians treating pulmonary arterial hypertension. It is defined as a complete morphological and functional recovery of the right heart chambers upon substantial reduction or near normalization of pulmonary vascular resistance obtained with PAH-specific therapy.An exact clinical definition is still missing, although the assessment of multiple morphological echocardiographic parameters such as RVEDA, right ventricular fractional area change (RVFAC), right atrial area, and left ventricular eccentricity index would be reasonable .Evidence has shown that patients who achieve right ventricular reverse remodeling have an excellent long-term survival and quality of life; however, it can be observed only in a small percentage of patients under treatment , 9.An important clue of the clinical relevance of achieving RHRR can be found in PAH patients undergoing lung transplantation, where early post-transplant normalization of mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance (PVR), and right ventricular ejection fraction was observed during the follow-up period in patients who underwent lung transplantation, regardless of the degree of pretransplant right ventricular dilatation and dysfunction, and tricuspid regurgitation .The impact of RV reverse remodeling on prognosis and survival has been also observed in group 4 pulmonary hypertension patients, whereas near-normalization of PVR achieved after successful pulmonary endarterectomy and balloon pulmonary angioplasty is associated with an important reduction in RV volumes and improvement in RV systolic function , with exRight heart reverse remodeling has recently become crucial for evaluating patients’ response to therapy. In fact, while a mild decrease in PVR achieved with less aggressive treatment strategies is associated with a lower probability of having right heart reverse remodeling, remarkable reductions in PVR associated with more aggressive therapies are associated with more significant improvements in right heart morphological and functional parameters .In a study conducted on treatment-naive idiopathic pulmonary arterial hypertension patients undergoing four different treatment approaches , the largest reduction in PVR occurred with initial parenteral prostanoid and single oral, with relevant improvement in RVEDA and RV fractional area change observed in patients with a large reduction in PVR (>40%) .This evidence has been confirmed in another cohort of patients with a severe form of PAH study treated with triple upfront combination of targeted therapies, where PVR decreased on average by 69%, and RHRR was observed in all patients, addressing that a time-sensitive and aggressive approach is crucial in order to restore right ventricular function and morphology .Medical treatment for PAH pulmonary is based on three main mechanisms: stimulating the nitric oxide–cyclic guanosine monophosphate , increasing prostacyclin effects on receptors , agonizing the prostacyclin receptor (selexipag), and antagonizing the endothelin pathway (bosentan and ambrisentan), all leading to vasodilation in the pulmonary vasculature .With the advent of disease-specific treatment, 5-year survival has doubled to more than 60% in the past 30 years. Current treatment consists of combination strategies, targeting more than 1 biological pathway, leading to a noteworthy improvement in morbidity and mortality compared with single-pathway targeted monotherapy , 17.The real turning point that has paved the way for upfront combination therapy in the treatment of pulmonary arterial hypertension has been the AMBITION trial . In this trial, the upfront combination of ambrisentan and tadalafil vs either drug alone determined a significant improvement in terms of event-free survival, as well as a 50% decrease from baseline in N-terminal pro-brain natriuretic peptide levels compared with the monotherapy group, a higher percentage of patients with a satisfactory clinical response and a greater improvement in the 6-min walk distance, in patients on double therapy compared to those on monotherapy, while no hemodynamic data was available from the trial .Right heart reverse remodeling is more constantly obtained by combined therapeutic strategies, and the likelihood of right heart reverse remodeling is a sigmoid function of decreased PVR, with > 50% RHRR observed when PVR decreases by > 50% .Upfront combination strategies seem to be more effective in terms of improving hemodynamics and RV morphology and function, and therefore slowing disease progression, compared with oral monotherapy, which is currently recommended by ESC/ERS guidelines only in specific settings of PAH patients .In fact, latest guidelines only recommend treatment with oral monotherapy in patients suffering from cardiopulmonary comorbidities from all risk categories. In this specific setting, patients tend to have a less brilliant response to PAH medication, are more likely to discontinue this medication due to lack of efficacy and tolerability, are less likely to reach a low-risk status, and have a higher mortality risk .Oral monotherapy with riociguat is recommended in patients affected by CTEPH .The positive effects of riociguat have been observed in terms of improved pulmonary artery remodeling, pulmonary hemodynamics, improved RV-PA coupling, improved RV function, reduced RA and RV dimensions, RV hypertrophy and fibrosis, reduced tricuspid regurgitation both in preclinical models and prospective randomized controlled phase III trials such as PATENT-1 and CHEST-1 .Apart from these settings, evidence shows that the effect monotherapy on afterload reduction is mild, with only a slight reduction in PVR after 3 to 6 months of treatment .More encouraging results were obtained in patients treated with high dose treprostinil s.c. and epoprostenol i.v. compared with oral drugs , 22, 23.The use of upfront combination with ERA+PDE5i for the treatment of low and intermediate risk patients without cardiopulmonary comorbidities is recommended by the latest guidelines. It is recommended to maintain this therapy also in patients that during follow-up belong to the low-risk category according to the four-risk strata model .Apart from the AMBITION study, the use of combination therapy is supported by other smaller real-life studies, which have proved that initial oral combination therapy can also significantly improve the hemodynamic status, with PVR reduction of 27–59% and mPAP reduction of 10–23% (from baseline) , 24.A recent multicenter retrospective analysis revealed that in newly diagnosed PH patients undergoing double upfront therapy with ambrisentan and tadalafil, in spite of the observed improvement REVEAL risk score in proportion to decreased PVR and preserved stroke volume, still 50% of these patients did not achieve low risk status and needed additional treatment .In patients who are at intermediate–low risk despite receiving double oral therapy with ERA+PDE5i, adding selexipag should be considered to reduce the risk of clinical worsening, but also switching from PDE5i to riociguat may also be considered .Evidence supporting these treatment strategies comes from randomized controlled trials such as the GRIPHON, where adding Selexipag in treatment naïve patients or on top of background therapy was associated with a reduced risk of clinical worsening events  and REPL2, SVI <31 mL/m2, and/or PVR ≥12 WU), and in patients presenting at intermediate-high or high risk at follow-up risk assessment, triple combination therapies with ERA+PDE5i and IV/SC PCA are recommended [According to the latest guidelines, in patients belonging to the high-risk group at baseline, in patients at intermediate risk presenting with severe haemodynamic impairment  and excellent long-term survival rates were observed in patients’ with severe PAH, defined by a PAPm >50 mmHg, who received early treatment and rapid uptitration with parenteral prostanoids in combination with background oral therapy .Early introduction and rapid uptitration of parenteral drugs were also proposed by Benza et al., who recently proposed the use of an implantable CardioMEMS to remotely monitor pulmonary hemodynamics and guide titration of parenteral prostacyclins. Within the first months of monitoring, patients underwent rapid uptitration in parenteral prostacyclin, and significant reductions in mPAP and an improvement in cardiac output were observed in response to therapy. Significant function and quality of life improvements were observed in the cohort within 1 year .On the other hand, data from an Italian study by Badagliacca and colleagues showed how late introduction of parenteral drugs was associated with scarce prognosis. This was relatable to the advanced clinical and hemodynamic condition of the patients, proving once again the importance of adopting early and aggressive treatment strategies in order improve the patients’ outcome and life expectancy .Currently approved PAH therapies, which act via the prostacyclin, endothelin or nitric oxide pathways, have radically modified the course of the disease; however, long-term prognosis remains poor. New therapeutic targets and novel therapies are needed to achieve low-risk status in a higher percentage of patients, and ultimately improve disease prognosis.Encouraging results have derived from the double-blind, randomized, placebo-controlled trials PULSAR and STELLAR, which evaluated the effect of sotatercept on top of background pulmonary arterial hypertension therapy.Sotatercept is a novel fusion protein composed of the extracellular domain of the human activin receptor type IIA fused to the Fc domain of human IgG1, acting as a ligand trap for members of the TGF-β superfamily and by balancing the growth-promoting activin growth differentiation factor pathway and the growth-inhibiting BMP pathway.−5 , while the least-squares mean difference between the sotatercept 0.7-mg group and the placebo group was −239.5 dyn · sec · cm−5 . Remarkable improvements in the 6MWT and NT-proBNP levels were also documented. Improvements in primary and secondary endpoints and clinical efficacy were confirmed in the extension period [In the phase 2 PULSAR trial, treatment with sotatercept determined an important reduction in pulmonary vascular resistance compared to placebo. The least-squares mean difference between the sotatercept 0.3-mg group and the placebo group in the change from baseline to week 24 in pulmonary vascular resistance was −145.8 dyn · sec · cmn period .The outstanding results were confirmed in the phase 3 trial (STELLAR), in which the patients were randomly assigned in a 1:1 ratio to receive subcutaneous sotatercept  or placebo every 3 weeks.The median change from baseline at week 24 in the 6-min walk distance was 34.4 m  in the sotatercept group and 1.0 m  in the placebo group. The first eight secondary end points were significantly improved with sotatercept as compared with placebo .A recently completed phase 2 randomized controlled trial, currently in the open label extension phase, evaluated the effect on improving hemodynamics determined by seralutinib (formerly known as GB002), a novel, potent, clinical stage inhibitor of PDGFRα/β, CSF1R, and c-KIT delivered via inhalation. In preclinical animal models, the drug reversed pulmonary vascular remodeling, improved hemodynamics, reduced circulating levels of N-terminal pro b-type natriuretic peptide (NT-proBNP), and increased lung BMPR2 protein expression compared to controls, while phase 1a and phase 1b trials proved that it was well tolerated .The ongoing phase 2b/phase 3 randomized controlled trial IMPAHCT aims to evaluate safety and efficacy of dry powder inhaled imatinib (AV-101) in patients with group 1 PAH. Imatinib is a small-molecule kinase inhibitor which inhibits tyrosine kinases involved in growth, differentiation, proliferation, survival, inflammation, metabolism and apoptosis , 39. ImaPatients treated with oral imatinib in the phase 2 study had a significant reduction in pulmonary vascular resistance and in the phase 3 randomized controlled trial (IMPRES) significant improvements in 6-min walk distance and haemodynamics were observed in the treatment group, yet with a high rate of adverse events , 45. In The phase 2b/phase 3 trials are ongoing, and primary endpoints include change from baseline in Pulmonary Vascular Resistance for the phase 2b study and in Six Minute Walk Distance (6MWD) for the phase 3 study after 24 weeks of treatment .53 , an inactive prodrug of Treprostinil, expected to provide extended release of Treprostinil in the lung, with the goals of less frequent dosing (once daily) and less recurrent and severe side effects associated with the currently approved forms of Treprostinil. Endpoints include change from baseline in PVR and 6MWD at week 16 of treatment Pulmonary arterial hypertension is still characterized by high mortality and morbidity. Data derived from studies and real-life experience suggest that a greater reduction in PVR is necessary to achieve reverse remodeling of the right ventricle in PAH, and consequently to improve clinical status and prognosis.Therefore, early and aggressive combination therapies are needed, especially in higher risk categories.Approved PAH therapies slow disease progression and improve life expectancy, although to date some patients do not achieve low-risk status with optimized medical therapy, and their long-term prognosis remains poor. New therapeutic targets and novel drugs are being investigated: remarkable results have derived from the phase II and III trials on Sotatercept, a subcutaneous drug with dosing every 3 weeks, and promising results are expected to come in the following years from several ongoing trials targeting new pathways for the treatment of pulmonary arterial hypertension.


In particular, we outline studies regarding neurodevelopmental disorders with pharmaco-resistant seizures and/or severe cognitive impairment that to date lack effective drug treatments in which SAHA could ameliorate defective neuroplasticity.Neuroplasticity is a crucial property of the central nervous system to change its activity in response to intrinsic or extrinsic stimuli. This is mainly achieved through the promotion of changes in the epigenome. One of the epi-drivers priming this process is suberoylanilide hydroxamic acid (SAHA or Vorinostat), a pan-histone deacetylase inhibitor that modulates and promotes neuroplasticity in healthy and disease conditions. Knowledge of the specific molecular changes induced by this epidrug is an important area of neuro-epigenetics for the identification of new compounds to treat cognition impairment and/or epilepsy. In this review, we summarize the findings obtained in cellular and animal models of various brain disorders, highlighting the multiple mechanisms activated by SAHA, such as improvement of memory, learning and behavior, and correction of faulty neuronal functioning. Supporting this evidence,  Neuroplasticity is a fundamental capacity of neurons to reorganize themselves in response to new information and/or sensory stimulation changing connections in the neuronal network. This complex process occurs most profoundly in the first few years of life as neurons grow very rapidly and send out multiple branches, ultimately forming many connections. Defects in this process may compromise brain development and functioning, as observed in several neurodevelopmental disorders (NDDs).In the last decade, many studies have been aimed at identifying neuroactive molecules capable of exerting a positive effect on the ability of neurons to reorganize the synaptic network . This brin vitro and in vivo. Several studies highlight that, similarly to other HDACIs, the therapeutic outcome of SAHA—effect, efficacy, effectiveness, and benefit—may vary depending on the dosage used and the biological context analyzed  [in vivo models coupled with fast transcriptome and proteome screenings may help to figure out the pharmacology response of SAHA to distinguish at molecular levels the advantages and disadvantages of SAHA, also compared to other HDAC inhibitors, allowing the adoption of personalized applicability of HDAC activity inhibition. Although pharmacogenomic studies for HDAC inhibitors are still scarce, genotype-directed dosing could improve pharmacotherapy of SAHA, reducing toxicity risk or suboptimal dosage. In view of more in-depth studies on the pharmacology response of SAHA, the main point of this review is to highlight the neuroplasticity property of SAHA that could be tested in animal models of neurological disorders that have not been tested to date, giving an overview of cellular and animal models tested, functional processes analyzed, and molecular pathways sensitive to this epi-treatment. In particular, this article aims to review studies on the broad capacity of SAHA in governing neuroplasticity, providing a more complete picture of its multiple activities—at both molecular and cellular levels—such as neuronal maturation, activation of autophagy, microtubule remodeling, and neurospecific splicing modulation  for the treatment of T-cell lymphoma  and permw, etc.) ,16,17,18w, etc.) ; (ii) Itw, etc.) ,16,17,18dulation  [11,13,1in vivo and in vitro treatments have shown that this activity has multiple downstream effects and is not restricted to a particular signaling pathway , a well-conserved disease gene involved in multiple NDDs [Caenorhabditis elegans animals. Behavioral phenotype analysis of alr-1-KO worm mutants revealed that SAHA rescued defective touch response, a behavioral defect affecting mechanosensory neurons [Kdm5C, a gene encoding a histone demethylase involved in NDD and also counteracts the defective transcription of Bdnf II and IV isoforms [Supporting this evidence of SAHA as a proneuronal molecule, we previously showed the activity of this epidrug counteracting the defective neuronal differentiation and maturation in animal and cellular models ablated for aristaless homeobox-related gene  and the formation and maintenance of synapses. Mechanistically, it is a complex catabolic process that delivers cytosolic components to lysosomes for degradation. SAHA has been shown to influence the autophagy pathway at various points and to protect the aged brain against plasticity impairment. This is what emerges from two recent studies showing that cognitive dysfunction induced by the anesthetic sevoflurane or insulin resistance can be counteracted by SAHA, through the expression control of autophagy-related gene markers, such as LC3 and P62 ,21. As fMicrotubules (MTs) are cylindrical cytoskeletal structures constituted by polymers of αβ-tubulin that play essential roles in many essential mammalian cell functions, such as cytoskeletal support and transportation of intracellular cargo, thus regulating neuroplasticity and synaptogenesis. The dynamic changes regulating MT structure and stability are mediated by acetylation of K40 in α-tubulin, a posttranslational modification, which marks the luminal surface of microtubules and is fundamental for microtubule stabilization and vesicle transportation. The dynamics between acetylation/deacetylation of α-tubulin is mediated by the action of acetyltransferases and deacetylases, respectively. Because of its HDACi activity, SAHA induces hyperacetylation of α-tubulin, facilitating sliding between filaments and making MTs more mechanically stable ,22 FiguC. A defeRelated to the acetylation/deacetylation effect of SAHA, Luo et al. (2022) underlined a new mechanism of action preventing axonal damage and neurological dysfunction in a rat model of subarachnoid hemorrhage (SAH). This SAHA-induced response is mediated by heat shock protein (HSP) co-inducer activity via the acetylation of HSP70, which in turn induces the degradation of TDP-43 aggregates .Alternative splicing (AS) is a critical process of posttranscriptional gene expression that diversifies and expands the proteome and increases the functional diversity of molecules implicated in mammalian brain development and plasticity ,50. CharDMPK) gene. These expanded repeats lead to the formation of hairpin structures affecting the DMPK mRNA (GC-rich foci), which in turn causes the sequestration of splicing regulators such as MBLN1, resulting in aberrant alternative splicing of a variety of mRNAs [In relation to the levels of histone acetylation, the opening and closing states of chromatin have the ability to influence exon inclusion and exclusion by recruiting directly splicing factors to sites of specific exons . Indeed,of mRNAs . The autRest+/ΔEx4 mice induces histone hyperacetylation, rescues defective gene expression of REST target genes, and subsequently induces improvement of cochlear defects [More interestingly, the daily intraperitoneal injections of SAHA in DM1 mice and the daily administration in DM1 patient-derived myoblasts counteract the aberrant splicing affecting myotonia genes  . Moreove defects .This section discusses the available evidence in relation to the therapeutic implications of SAHA in a selected number of neurological diseases, affecting the early phases of brain development and characterized by severe cognition impairment and/or pharmaco-resistant epilepsy. Depending on the disease context, studies carried out in animal and cellular models agree that SAHA exerts neuroprotective and neuritogenic effects . Given SFmr1-KO, restores object location memory and passive avoidance memory and corrects repetitive behavior and social interaction deficits [Fmr1-KO mice is not linked to all behavioral abnormalities [Fragile X syndrome (FXS) is the most frequent inherited form of intellectual disability (ID) and autism spectrum disorder (ASD), caused by the silencing of the FMR1 gene and, subsequently, the loss of its encoded protein, fragile X mental retardation 1 protein (FMRP) . FMRP prdeficits   which is the major mediator of the cognitive-behavioral alterations in 7Dup, responsible for a large part of transcriptional dysregulation. Of note, a symmetrically opposite hemi-deletion of the same region causes Williams–Beuren Syndrome (WBS), a multisystemic disease, including hypersociability and selectively spared verbal abilities, mild to moderate ID, and a severely compromised visual-spatial processing [GTF2I expression [Autism spectrum disorder (ASD) is a neurodevelopmental disorder affecting almost 1% of children, characterized by impairments in language and social interaction coupled with various degrees of intellectual disability (ID) . Severalocessing . These tocessing   capable to stop and/or counteract the events transforming functional neuronal circuits into epileptic circuits (epileptogenesis) and consequently generating seizures (ictogenesis) ,70,71. EKcna1 that encodes the voltage-gated Kv1.1 potassium channel α-subunit, SAHA is capable to reduce daily seizure activity [kcna1-KO zebrafish larvae with SAHA for 30 min completely abolished the high-frequency spikes and thus hyperexcitability. Furthermore, they treated spontaneously epileptic Kcna1-null mice with SAHA and observed, using video EEG, reduced seizure frequency by 60%, a phenomenon that started 24 h after the start of the treatment and took 4 days to reach significance, indicating that SAHA activity requires additional time to be effective [Recent studies have highlighted the promising use of SAHA as a potent anticonvulsant drug with limited off-target activity . Since Sactivity   with an inherited dominant form of postlingual progressive hearing loss [REST-containing DFNA27 locus on chromosome 4q12-q13.1 [Rest+/ΔEx4 mice and to correct the stereocilia in the inner and outer hair cells of organs of Corti cultures. More interestingly, the systematic administration of SAHA in REST exon 4-deficient newborn mice—when the BBB is still not fully developed—was able to strongly improve the formation of stereocilia in the outer hair cells of the Corti organ [In addition, they demonstrated that the combined formulation of SAHA with rosiglitazone significantly reduced both the expression levels of the neuroinflammatory markers IL6 and TNF-a and the oxidative stress markers MDA and nitrite and restored GSH and SOD levels . In linetylation —and redutylation . Interestylation . In a motylation . This caEST gene . In humaing loss . Specifi12-q13.1 . Subsequ12-q13.1  identifi12-q13.1 . The autti organ . Recentlti organ , perhapsti organ .Bdnf) or counteracting oxidative stress [The combination of neuroprotective and neuritogenic effects observed in SAHA strengthens its potential for drug repurposing in the treatment of cognition impairment and epilepsy, overcoming contradictory observations reported in the previous literature about its neuroprotective or neurotoxic effects on the CNS that may depend on target cells and tissues, as well as the dosage used ,39. Indee stress ,61,77,78in vivo features of NDD phenotypes may clarify the promising therapeutic applications.The diversity of SAHA-sensitive pathways is not a surprise because this HDACi has two wide effects: (i) it induces hyperacetylation of histones H3 and H4 modifies global chromatin compaction and transcriptional gene expression; and (ii) it induces hyperacetylation of nonhistone proteins involved in different cellular functions, including neurogenesis and synaptogenesis. However, the effects of SAHA on the course of different neurological diseases are only partly understood, and further studies in complementary preclinical models and in patient-derived cortical brain organoids that recapitulate Given the potential of SAHA as a particularly promising repurposed compound for NDDs, a better comprehension of the mechanism(s) of action may represent the road ahead for personalized medicine and insights into potential pharmacological approaches to modulating neuronal functions during the early stages of the disease.


Immune cell infiltration occurs in the tumor microenvironment (TME) and influences cancer progression through interaction with tumor cells. Runt-related transcription factors (RUNXs), including RUNX1–3, are the master regulators of development and differentiation and are all important to the development of immune cells. However, the role of RUNXs in the immune cells of TME remains unclear. In this study, we first used online related databases and related low-grade glioma (LGG) data from TCGA and CGGA to conduct bioinformatics analysis. The analysis confirmed that RUNXs were significantly and positively correlated with immune infiltration in multiple tumors, especially in LGG and there was the highest correlation between RUNXs and the progress and prognosis of LGG. Furthermore, the functional enrichment analysis revealed that RUNXs might be involved in the inflammatory and immune responses of the biological processes, and RUNXs were tightly associated with the multiple immune checkpoint molecules. Subsequent results confirmed that RUNX1, as an independent prognostic factor for LGG, may target interferon-gamma receptor 2 (IFNGR2) to regulate glioma cell proliferation, invasion, and migration. Besides, we also found that the expression levels of RUNX1 and IFNGR2 were significantly reduced, and their correlation was enhanced in the IDH-mutant subtype. Patients with a high expression of RUNX1 and/or IFNGR2 (HH/H) in the IDH-mutant subtype showed poorer prognosis and significantly increased infiltration of M2 macrophages. This finding implied the possible key role of RUNX1 in the differentiation of IDH mutant subtypes as well as in the formation of TME infiltration signatures by monitoring IFNGR2. Glioma is the most common primary tumor in the central nervous system. According to the 2021 new classification specified by the World Health Organization (WHO), adult-type diffuse gliomas can mainly be categorized into three histological subtypes: (1) Astrocytoma, (2) Oligodendroglioma, and 3) Glioblastoma  Glioblas. LGG canDysregulation of transcription factors induced by gene mutations is the key factor contributing to the occurrence of cancer . Runt-reIn our past studies, we first conducted a comprehensive assessment of the differential expression of RUNXs in various types of human cancers, analyzed the correlation between RUNXs expression and immune infiltration in the TME of different solid tumors, assessed the prognostic significance of their expression and the closer co-relationship between RUNXs and immune infiltration, and verified the prognosis of LGG. We further investigated the relationship between RUNXs and common immune checkpoints in LGG. The independent prognostic value of RUNX1, RUNX2, and RUNX3 in LGG was analyzed by Multivariate Cox regression analysis and then further verified with reference to the specific data of The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA). Finally, RUNX1 and its target gene interferon-gamma receptor 2 (IFNGR2) were associated with growth, apoptosis, invasion, and migration of LGG cells, as well as immune infiltration and poor prognosis of LGG. Further analysis clarified that RUNX1 may be involved in the refinement of the LGG IDH mutation subtypes and immune infiltration by regulating IFNGR2.The present results provide novel insights into the functional role of RUNXs in LGG. Accordingly, we conclude that RUNX1 represents the family of RUNXs as an independent risk factor for LGG and may serve as a molecular target for IDH mutant subtype refinement and immunotherapy. Thus, there is a need to highlight the potential mechanistic basis for RUNXs to influence immune cell–tumor interactions.As a comprehensive database and an integrated data mining platform, the Oncomine database (www.oncomine.org) contains 715 gene expression datasets from 86,733 samples . Therefohttps://cistrome.shinyapps.io/timer/)  < 0.02), 6628 genes (blue) showed significant positive correlations with RUNX2 , and 6368 genes (red) showed significant positive correlations with RUNX3 . Among these, 4608 genes were enriched by three of them, suggesting a widespread impact of RUNXs on the transcriptome in LGG. The top 20 genes they targeted together were used to construct the PPI network via the GeneMANIA  –5E. GO tTumor immunotherapy is a strategy employed in the treatment of malignant tumors by applying the cytotoxic potential of the human immune system. Immune checkpoints and their ligands are often upregulated in the TME of different malignant tumors, which forms an important obstacle to inducing an effective anti-tumor immune response . In receWe further explored the relationship between the different RUNXs expression and the abundance of tumor-infiltrating lymphocytes (TILs) through TISIDB analysis and found that RUNX1, RUNX2, and RUNX3 were positively correlated with TILs . Moreovehttps://www.cbioportal.org/) [http://www.cgga.org.cn/). Patients with grade 2 or 3 LGG defined by WHO and complete clinical and transcriptional data were included for analysis in this study. A similar restricted coexpression pattern was verified through TCGA cohort (n ═ 514) and CGGA cohort (n ═ 182) analyses, and the significant positive correlation between RUNXs and the abovementioned checkpoint immune molecules is illustrated in Subsequently, in order to avoid any possible bias, we downloaded the clinical data, gene expression data of patients with LGG from the TCGA database   and the al.org/)  . However, RUNX2 and RUNX3 lose their independent prognostic value in the presence of RUNX1  and RUNXs expression using the TIMER database confirmed that age and RUNXs expression are independent prognostic factors . In addition, the outcome of LGG patients with a high expression of IFNGR2 was worse . In addition, a positive correlation was noted between RUNX1 and IFNGR2 expression in LGG, as verified with reference to the TCGA and CGGA cohort analysis . These results confirmed that RUNX1 could monitor the expression of IFNGR2 and participate in the LGG progression by regulating the STAT5 signaling pathway. In turn, it affected the TME of LGG and its response to immunotherapy to a certain extent, although the exact underlying mechanism warrants further experimental verification.Accordingly, we examined the IFNGR2 protein expression and mRNA expression after overexpression and knockdown of RUNX1 using two LGG cell lines, namely, SW1088 and HS683, and found that RUNX1 could regulate the expression and transcription of IFNGR2 –9F. We aClinically, LGG patients can be classified into IDH WT and IDH mutant-type according to the characteristics of IDH, and the IDH mutations were associated with prolonged overall LGG survival , 46.It has been reported that RUNX1 and its target gene REXO2 are upregulated in the IDH WT subgroup, which is related to the poor prognosis of IDH WT LGG . Our stuThe degree of immune infiltration in different subtypes of LGG and the prognosis of corresponding patients were different . Past stThe conventional method of tumor treatment involved killing the cancer cells “with the help of external forces” through surgery, radiotherapy, and chemotherapy, while tumor immunotherapy was employed to “attack” cancer cells from within by awakening the autoimmunity system. More emphasis was placed on the key role of the surrounding environment in the occurrence, development, and metastasis of cancer , 51. TMETranscription factors control chromatin and transcription by identifying specific DNA sequences, which together form a complex system that guides the expression of a genome. They form the basis of human physiology, diseases, and mutations, and participate in the occurrence and development of cancer and other diseases , accountIn the present study, we first performed a pan-cancer analysis of the expression of RUNXs and then demonstrated that RUNX1, RUNX2, and RUNX3 are highly expressed in various cancers. We also verified the different clinical and prognostic roles of RUNX1, RUNX2, and RUNX3 mRNA expressions as well as the correlation between them and immune infiltration in different solid tumors. For the first time in literature, we have reported a significant positive correlation between RUNXs and immune infiltration in diverse cancers. Immune infiltration analyses suggested that RUNX1, RUNX2, and RUNX3 all showed a strong positive correlation with immune infiltration in LGG, but a significant negative correlation with the prognosis of patients with LGG.LGG includes grade 2 and 3 gliomas, accounting for 43.2% of primary intracranial gliomas . WithoutIt has been demonstrated that the immunological characteristics of the TME vary significantly among different subtypes of LGG . The assAlthough the LGG grade is relatively low, its recurrence rate is high and it is easy to transform to a higher grade . The proOur study findings revealed that RUNX1 and macrophages can act as independent prognostic factors of LGG through multivariate Cox regression analysis, and there exists an obvious positive correlation between RUNX1 and IFNGR2. In response to immune monitoring, multiple immune cells were found to functionally migrate to the tumor sites and trigger anti-tumor immunity through the release of a series of cytotoxic factors, such as interferon (IFN)-γ, tumor necrosis factor (TNF)-α and CD95 ligand (FasL), and TNF-related apoptosis-inducing ligand (TRAIL) . In addiLGG is highly heterogeneous, existing with multiple subtypes. It has also been reported that IDH mutant type LGG presents with a better prognosis when compared with the IDH wild subtypes . SignifiThe TME is created by tumors. Immune cells in the TME not only exert anti-tumor effects but also promote tumor growth , 82. PasWe obtained three RUNX genes  that were significantly negatively associated with the prognosis of LGG patients. Multivariate Cox regression analysis further established RUNX1 and macrophages as independent prognostic factors for LGG. We also found that RUNX1 can regulate the transcription and expression of IFNGR2 and is involved in the regulation of glioma cell proliferation, cycle, apoptosis, invasion, and migration, and the differentiation process of glioma mutant subtypes. RUNX1 and IFNGR2 can serve as the most important potential therapeutic and prognostic target.https://www.bjbms.org/ojs/index.php/bjbms/article/view/8086/2749.Supplementary data are available at the following link:


The monomeric GTPase Rab27 regulates exocytosis of a broad range of vesicles in multicellular organisms. Several effectors bind GTP-bound Rab27a and/or Rab27b on secretory vesicles to execute a series of exocytic steps, such as vesicle maturation, movement along microtubules, anchoring within the peripheral F-actin network, and tethering to the plasma membrane, via interactions with specific proteins and membrane lipids in a local milieu. Although Rab27 effectors generally promote exocytosis, they can also temporarily restrict it when they are involved in the rate-limiting step. Genetic alterations in Rab27-related molecules cause discrete diseases manifesting pigment dilution and immunodeficiency, and can also affect common diseases such as diabetes and cancer in complex ways. Although the function and mechanism of action of these effectors have been explored, it is unclear how multiple effectors act in coordination within a cell to regulate the secretory process as a whole. It seems that Rab27 and various effectors constitutively reside on individual vesicles to perform consecutive exocytic steps. The present review describes the unique properties and in vivo roles of the Rab27 system, and the functional relationship among different effectors coexpressed in single cells, with pancreatic beta cells used as an example. Exocytosis comprises multiple steps, from vesicle biogenesis to fusion with the plasma membrane. Rab27 and its effectors are specifically located on secretory vesicles and are thought to play versatile and critical roles in their transport from the cell interior to the vicinity of the plasma membrane  and lysosome-related organelles derived from connections with endosomes  and is catalyzed by Rab geranylgeranyl transferase (RGGT) . The genCaenorhabditis elegans ortholog of Rab3GEP/DENN/MADD (The guanine nucleotide binding state of Rabs is regulated by guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). AEX-3, the While GEFs for Rabs such as Rab3GEP generally contain a DENN domain . In contleaden mice , RUND-1, and CCCP-1, function in the sorting of cargos during granule maturation  and are released upon fusion of MVEs to the plasma membrane . ExosomeThe involvement of Rab27 in exosome biogenesis and release suggests a role in cancer progression (Our understanding of the in vivo functions and mechanisms of action of the Rab27 effectors, with the exception of exophilin-9, has grown markedly in recent years. Nevertheless, the precise mechanisms by which individual effectors act through their molecular interactions remains elusive. Moreover, almost nothing is known about the functional hierarchy and redundancy among the different Rab27 effectors expressed in the same cell and which regulate the whole process of vesicle exocytosis. Further investigation is required to resolve these issues.


This is particularly timely since in the past 6 months a new wave of strong clinical level evidence has supported the efficacy of B cell targeting in SSc skin and lung involvement.SSc carries the highest morbidity and mortality across CTD. Effective treatment and clinical control of the disease remain challenging. Currently available treatment approaches slow disease progression while recent trials have informed new treatment strategies to help patients. In this issue of Although the pathogenesis of SSc is incompletely understood, three pathogenetic mechanisms have been identified as crucial: endothelial abnormalities with vascular damage, imbalance of immune system with inflammatory burden, and fibroblast activation with extensive extracellular matrix deposition and fibrosis.A dynamic interplay between these mechanisms in different disease stages is the core of the most credited pathophysiological model of SSc. Understanding the dominant pathogenic driver of cutaneous and other organ involvement in each stage of the disease could guide selection of appropriate therapeutic interventions within the heterogeneity and complexity of the spectrum of clinical manifestations in SSc.Sakkas and colleagues reviewed the crucial role of B cells and underlined the recent evidence on B cell abnormalities in SSc disease , 2. MultThere are extensive reports of B cells in biopsies of organs affected by SSc, such as skin, lung and gastrointestinal tract. Multi-omic approaches have indicated their activated phenotype as well as their roles beyond being the source of autoantibody-secreting cells, including inflammatory and profibrotic cytokine secretion, loss of regulatory properties, and through crosstalk with numerous other cells including endothelial cells, vascular smooth muscle cells, T cells, dendritic cells, other immune cells and, finally, fibroblasts.et al. review a recent study revealing that Topo I-autoreactive B cells produce a variety of cytokines depending on the affinity of their B cell receptor to Topo-I. In particular, B cells with high affinity for Topo-I showed a profibrotic profile due to proinflammatory cytokine production and proinflammatory TH17 polarization, while B cells with low affinity for Topo-I were antifibrotic due to anti-inflammatory cytokine production and induction of regulatory T cells.The role of SSc-specific antibodies in predicting progression to disease in patients with Raynaud’s phenomenon has been recently validated in a large multicentre European cohort . FurtherThese findings further support the notion that restoring B cell homeostasis in scleroderma with specific intervention could promote disease control. In this context the use of chimeric antigen receptor-T (Car-T) cells targeting CD19 or B cell receptor with high affinity for anti-Topo-I might be a future innovative therapeutic strategy for SSc as it has been recently proposed for refractory SLE .Parallel to this line of evidence, in SSc there is an imbalance in effector and regulatory functions of B cells due to an increase in B cell secretion of proinflammatory cytokine IL-6 and autoantibodies, and a reduction of secretion of anti-inflammatory cytokine IL-10 .Considering the growing evidence supporting the role of B cells in SSc, rituximab (RTX) has been used in everyday clinical practice although not licensed in Europe or the USA for this clinical indication. Its use was supported by numerous clinical studies that evaluated the safety and efficacy of this therapeutic agent published since 2009 and the pooled results of meta-analysis reporting that RTX was associated with improvement in skin score and stabilized lung involvement . The rea+ B cells and a high baseline skin score exhibited the greatest improvement in skin involvement [The DesiReS trial was a Japanese double-blind, investigator-initiated, randomized, placebo-controlled trial that demonstrated the efficacy of RTX in reducing skin score at 24 weeks in patients with SSC. Further, a machine learning analysis of this trial showed that SSc patients with a high level of CD19The RECITAL trial was a randomized, double-blind, phase 2b trial to assess the superiority of RTX compared with cyclophosphamide in patients with severe or progressive interstitial lung disease (ILD) related to SSc, idiopathic inflammatory myositis, or mixed connective tissue disease . RTX was2 once per week for 4 weeks, respectively), enrolment populations, and comparison with active treatment arm or placebo, confirmed that RTX is an effective treatment in SSc skin fibrosis and in patients with ILD related to connective tissue disease. The efficacy of RTX in apparently different diseases with similar organ involvement suggests that targeting B cells could represent an appropriate approach in a broad spectrum of connective tissue diseases with shared pathogenic pathways.Results of RECITAL and DesiReS, despite the differences in drug administration regimens (1000 mg at weeks 0 and 2 and 375/mIndeed, these developments in SSc parallel the development of B cell targeted therapy in the other rheumatic diseases, rheumatoid arthritis, systemic lupus erythematosus, inflammatory myositis and ANCA vasculitis. In each case, compelling case series evidence has preceded, and often superseded, the more complex evidence from randomized trials , 11. FurTaken altogether, the evidence currently available suggests that the present therapeutic paradigm, to implement the treatment or employ immunosuppressants only when overt SSc clinical manifestations or organ damage ensue, is poised to evolve towards a molecular or biologically driven strategy to pre-empt tissue fibrosis, exploiting a ‘window of opportunity’ to treat patients with SSc before they developed organ damage.In our opinion, the evidence from DesiReS and Recital and the evidence from the recent large trials of nintedanib in SSc-ILD  support


Chlamydomonas reinhardtii (Chlamydomonas) suggested that the activity of triose phosphate/inorganic phosphate translocators (TPTs) exceeds that of the malate-OAA reductant shuttle, thereby allowing the export of organic carbon while maintaining chloroplast phosphate homeostasis  cycle from the chloroplast. Metabolic flux analysis during heterotrophic growth of the model green alga eostasis . HoweverTPT2 and TPT3 in budding yeast allowed the reconstitution of translocator-containing liposomes. Subsequent liposome assays for the rate of triose phosphate/Pi exchange showed that both translocators have a typical TPT substrate spectrum and a similar substrate preference for dihydroxyacetone phosphate and 3-phosphoglycerate.The presence of TPTs in Chlamydomonas was investigated based on homology analysis with Arabidopsis TPTs. Of all TPT candidates, TPT2, TPT3, TPT10, and CGL51 contained a predicted chloroplast transit peptide. TPT2 and TPT3 were selected for further analysis based on their similarities with plant TPTs  and hightpt2 and tpt3 knockouts were generated using CRISPR/Cas9. Under photoautotrophic and heterotrophic conditions, tpt2 growth was inhibited only by high light, whereas tpt3 grew poorly even in low light and could not grow under moderate or high-light conditions. Lugol and Nile red staining revealed high levels of starch and lipid accumulation in tpt3 mutants but not in the wild-type cells following exposure to high light. These results suggest that TPT3 is important for the export of energy/fixed carbon from the chloroplast, particularly under high-light conditions. Furthermore, whereas other sugar transporters seemed to be able to partially compensate for the loss of TPT2, there appeared to be little compensation for the loss of TPT3. The tpt3 mutant phenotype was unexpectedly severe compared with known mutants in higher plants where transporters mostly compensate one another.To further investigate the function of these chloroplastic TPTs, tpt3 mutant contained a larger pool of glycolytic/gluconeogenic/CBB cycle intermediates but similar or lower levels of TCA and glyoxylate cycle intermediates compared with the wild-type cells. These results confirmed the function of TPT3 in the export of photosynthetic products and support the hypothesis that triose-P export drives the cytosolic segment of glycolysis and downstream metabolic pathways. Moreover, these findings confirm that the flux of fixed carbon as hexose-P from the chloroplast is negligible in Chlamydomonas (tpt3 was related to photosystem II damage, as revealed by a reduced oxygen evolution rate and photosystem II yield. In addition, tpt3 showed hyper-reduction of the photosynthetic electron transport chain, a higher plastoquinone pool reduction state, and a slower rate of photosystem I oxidation. Additionally, with increasing light intensity, tpt3 accumulated higher levels of reactive oxygen species in the stroma, cytosol, and nucleus than the wild-type cells. Surprisingly, the reactive oxygen species levels were lower in mitochondria, which might be due to lower activity of the mitochondrial electron transport chain as a consequence of lower carbon export from the chloroplast. All these observations are consistent with a bottleneck in the export of CBB cycle products from the chloroplast in tpt3, which causes saturation of the chloroplast photosynthetic capacity, even in moderately low-light conditions (see A comparative metabolite analysis showed that the ydomonas . The ligions see ..This study highlights the importance of TPTs in carbon and energy export from chloroplasts and provides new insights into the metabolic pathways that drive the growth and adaptation of microalgae in response to different light intensities. Understanding these pathways creates opportunities to tailor microalgae for the biotechnological production of lipids, starch, and other bioproducts.