基于JNK/Nrf2/HO-1通路探讨芝麻酚对ox-LDL诱导的血管内皮细胞损伤的影响OA

Aim To explore the antagonistic effect of sesamol on endothelial cell injury induced by oxidized low density lipoprotein(ox-LDL),and elucidate its molecular mechanism of exerting antioxidant stress,inhibiting abnormal angiogenesis and blocking endothelial-to-mesenchymal transition(EndMT)through the JNK/Nrf2/HO-1 pathway.Methods Human umbilical vein endothelial cells and human aortic endothelial cells were used to establish an endothelial cell injury model induced by 75 μmol/L ox-LDL.The CCK-8 method,DCFH-DA fluorescent probe and Annexin V/PI apoptosis detection method were used to evaluate the safety of sesamol and its effects on cell viability,as well as its protec-tive effects against oxidative stress and cell apoptosis;Matrigel tubular formation experiment,Transwell migration/invasion experiment RT-qPCR,immunofluorescence and Western blot techniques were used to detect the effects of sesamol on ab-normal angiogenesis,endothelial barrier function and EndMT;time gradient Western blot,JNK inhibitor SP600125 inter-vention and immunofluorescence experiments were used to verify the activation and necessity of the JNK/Nrf2/HO-1 path-way.Results The oxidative stress model of endothelial cells was successfully established by stimulating with 75 μmol/L ox-LDL for 24 hours,which showed a significant increase in reactive oxygen species(ROS)levels,upregulation of inflammation/adhesion molecule expression,downregulation of endothelial nitric oxide synthase(eNOS)and vascular endo-thelial cadherin expression,and an increase in cell apoptosis rate(P<0.05 or P<0.01).Sesamol(≤50 μmol/L)was non-toxic to normal endothelial cells;among them,50 μmol/L sesamol could significantly restore the decrease in cell via-bility induced by ox-LDL,inhibit ROS generation and cell apoptosis(P<0.05 or P<0.01);simultaneously,it could sig-nificantly inhibit the formation of abnormal tube braching points and cell migration,downregulate the expression of vascular endothelial growth factor/vascular endothelial growth factor receptor 2 and matrix metalloproteinase-9,upregulate the ex-pression of zonula occludens-1,claudin-5,and VE-cadherin,and restore nitric oxide production(P<0.05 or P<0.01);in addition,this concentration of sesamol could reverse EndMT-related phenotypes,reduce the expression of mesenchymal markers such as α-smooth muscle actin and vimentin,and restore the expression levels of CD31 and VE-cadherin(P<0.05 or P<0.01).Mechanism studies showed that sesamol could time-dependently activate the expression of p-JNK,nuclear Nrf2,and downstream HO-1(P<0.01);the JNK inhibitor SP600125 could block the nuclear translocation of Nrf2 and in-hibit the protective effect of sesamin(P<0.01).Conclusion Sesamol can significantly antagonize the injury of vas-cular endothelial cells induced by ox-LDL,and its mechanism is related to the activation of JNK/Nrf2/HO-1 pathway,inhi-bition of oxidative stress,abnormal angiogenesis and EndMT induced by ox-LDL,which provides an important experimental basis for its use as a potential natural drug to prevent and treat atherosclerosis.