Small, Thin Graphene Oxide Is Anti-inflammatory Activating Nuclear Factor Erythroid 2-Related Factor 2 via Metabolic Reprogramming.
Graphene oxide (GO), an oxidized form of graphene, has potential applications in biomedical research. However, how GO interacts with biological systems, including the innate immune system, is poorly understood. Here, we elucidate the effects of GO sheets on macrophages, identifying distinctive effects of GO on the inflammatory phenotype. Small, thin (s)-GO dose-dependently inhibited release of interleukin (IL)-1β and IL-6 but not tumor necrosis factor α. NLRP3 inflammasome and caspase-1 activation was not affected. The effect of s-GO was pretranslational, as s-GO blocked Toll-like receptor 4-dependent expression of Il1b and Il6 but not Nlrp3 or Tnf mRNA transcripts. s-GO was internalized by immortalized bone-marrow-derived macrophages, suggesting a potential intracellular action. Uptake of polystyrene beads with similar lateral dimensions and surface charge did not phenocopy the effects of s-GO, suggesting that s-GO-mediated inhibition of interleukin expression was not simply due to particle phagocytosis. RNA-Seq analysis established that s-GO had profound effects on the immunometabolism of the cells, leading to activation of the transcription factor nuclear factor erythroid 2-related factor 2, which inhibited expression of cytokines such as IL-1β and IL-6. Thus, we have identified immunometabolic effects of GO that reveal another dimension to its effects on cells. These findings suggest that s-GO may be used as a valuable tool to generate further insights into inflammatory mechanisms and indicate its potential applications in biomedicine.
['Hoyle|Christopher|C|', 'Rivers-Auty|Jack|J|', 'Lemarchand|Eloïse|E|', 'Vranic|Sandra|S|0000-0002-6653-7156', 'Wang|Emily|E|', 'Buggio|Maurizio|M|', 'Rothwell|Nancy J|NJ|', 'Allan|Stuart M|SM|', 'Kostarelos|Kostas|K|0000-0002-2224-6672', 'Brough|David|D|0000-0002-2250-2381']
D000818:Animals D002470:Cell Survival D002478:Cells, Cultured D016207:Cytokines D006108:Graphite D058847:Inflammasomes D008264:Macrophages D008810:Mice, Inbred C57BL D051267:NF-E2-Related Factor 2 D009457:Neuroglia D012333:RNA, Messenger D051197:Toll-Like Receptor 4 D014409:Tumor Necrosis Factor-alpha
graphene oxide macrophage NLRP3 inflammasome immunometabolism IL-1β inflammation