Mitigation of isoquercitrin on β-lactoglobulin glycation: Insight into the mechanisms by mass spectrometry and interaction analysis.
Formation of advanced glycation end products (AGEs) on foods imposes threats to human health after intaking. This research firstly evaluated the inhibition of isoquercitrin on β-lactoglobulin (β-Lg) glycation, the mechanisms were elucidated by fluorescence spectroscopy, Orbitrap MSn and molecular docking. Fluorescence spectra indicated that isoquercitrin effectively alleviated the formation of AGEs, it could stabilize the conformation structure of glycated β-Lg (G-β-Lg), change the micro-environment in the vicinity of chromophores. SDS-PAGE analysis revealed the suppressed cross-linking of G-β-Lg induced by isoquercitrin. The number of glycation site detected on G-β-Lg was reduced from ten to eight after the addition of isoquercitrin, and the relative glycation degree of substitution of per site (RGDSP) of most glycation sites were also greatly decreased. As indicated by intermolecular interaction, isoquercitrin quenched the fluorescence of β-Lg via a static mechanism, and their combination is an endothermic processing mainly derived by hydrophobic interaction, hydrogen bonds, and van der Waals forces. Isoquercitrin interacted with β-Lg to form an equimolar complex, and one hydrogen bond was formed between isoquercitrin and Lys69 (4.96 Å). Above results proved that isoquercitrin can be a promising anti-glycation agent used in food system to prevent the formation of harmful glycation products.
['Ma|Tian-Xin|TX|', 'Zhang|Lu|L|', 'Xu|Liang|L|', 'Ye|Yun-Hua|YH|', 'Huang|Tao|T|', 'Zhou|Qi-Ming|QM|', 'Liu|Hai-Long|HL|']
D000818:Animals D002417:Cattle D017127:Glycation End Products, Advanced D006031:Glycosylation D006860:Hydrogen Bonding D057927:Hydrophobic and Hydrophilic Interactions D007782:Lactoglobulins D013058:Mass Spectrometry D062105:Molecular Docking Simulation D011794:Quercetin D013050:Spectrometry, Fluorescence
Isoquercitrin Intermolecular interaction Anti-glycation Orbitrap MS(n) Structural changes