NMR-based Metabolomic Analysis For Mechanisms Of Both Protections Of HDL And ApoA-I Mimetic Peptide D-4F,and Injury Of Contrast Media On Endothelial Cells

Cell metabolomics is being used to reveal comprehensive and dynamic metabolic alterations in cells,which integrates high throughput detection technology and several data analysis methods.It plays a vital role in drug research.In this thesis,we conducted nuclear magnetic resonance(NMR)-based cell metabolomic analysis to elucidate the molecular mechanisms underlying the effects of drugs on endothelial cell metabolisms.Previous works have demonstrated that the apoA-I mimetic peptide,D-4F,exhibited numerous endothelial protective effects similarly to high-density lipoprotein(HDL).However,it is still elusive whether the endothelial protection mechanism of D-4F is exactly the same as that of HDL.Hence,we performed 1H NMR-based metabolomic analysis to compare the protective effects of HDL and D-4F against oxidized low-density lipoprotein(ox-LDL)-triggered endothelial cell dysfunction.We found that ox-LDL not only induced inhibitory migration of endothelial cells,but also leaded to metabolic disturbance,mainly embodied in perturbing glycolysis,glycerophospholipid metabolism and metabolic pathways related to oxidative stress.Treatment with eitehr HDL or D-4F ameliorated migration inhibition,oxidative stress and glycolysis abnormality impaired by ox-LDL.Moreover,ox-LDL-perturbed glycerophospholipid metabolism could be partly attenuated by HDL rather than D-4F.These results suggested that D-4F could not completely substitute HDL to exert the identical endothelial protective effect.This work provides a theoretical basis for developing the clinical application of D-4F.The use of contrast media can damage endothelial cells,leading to organ-specific and general side effects.But so far,the molecular mechanism underlying the injury effects of constrast media on endothelial cells has not been well-understood.In this work,we performed 1H NMR-based metabolomic analysis to address the metabolic changes in endothelial cells exposed to two kinds of contrast media with two doses.The results displayed that both contrast media exerted significant influences on the metabolic profiles of endothelial cells,and resulted in metabolic disorder via similar molecular mechanisms.We found that oxidative stress might be one of the main factors significantly responsible for endothelial cell dysfunction.Oxidative stress activated the antioxidant system of endothelial cells,promoted the biosynthesis of glutathione,and consumed a large amount of glutathione.Additionally,contrast media caused glycolysis abnormality,promoted TCA cycle anaplerotic flux,and suppressed choline metabolism.These results revealed contrast media-induced endothelial cell dysfunction from the perspective of metabolomics,which may be helpful for further exploring the pathogenesis of contrast media-triggered side effects.