Aim To investigates whether sphingosine-1-phosphate(S1P)regulates the expression of mitochon-drial calcium uniporter(MCU)via the sphingosine-1-phosphate receptor/proline-rich tyrosine kinase 2(S1PR/Pyk2)sig-naling pathway,thereby reducing oxidative stress-induced mitochondrial damage and inhibiting mitochondria-related apopto-sis.Methods Human umbilical vein endothelial cells(HUVEC)were subjected to oxidative damage using hydrogen peroxide(H2O2)as a model.Different concentrations of S1P were applied to the oxidative damaged HUVEC.Addi-tionally,the S1PR1 agonist SEW2871,the S1PR1 inhibitor W146,and the Pyk2 inhibitor PF-562271 were used to explore the specific mechanism of S1P action.Results S1P treatment significantly alleviated oxidative damage in HUVEC and was accompanied by an increase in S1PR1 expression(P<0.05),while S1PR3 expression remained unchanged.Mean-while,the expression levels of Pyk2 and MCU decreased(P<0.05).SEW2871 further reduced mitochondrial damage,whereas W146 exacerbated it(P<0.05).Furthermore,the application of the Pyk2 inhibitor PF-562271 also reduced H2O2-induced mitochondrial damage(P<0.05),further confirming the role of Pyk2 in this process.Conclusion S1P reduces H2O2-induced mitochondrial damage and inhibits mitochondria-related apoptosis in HUVEC by suppressing Pyk2 expression via S1PR1.

Aim To investigates whether sphingosine-1-phosphate(S1P)regulates the expression of mitochon-drial calcium uniporter(MCU)via the sphingosine-1-phosphate receptor/proline-rich tyrosine kinase 2(S1PR/Pyk2)sig-naling pathway,thereby reducing oxidative stress-induced mitochondrial damage and inhibiting mitochondria-related apopto-sis.Methods Human umbilical vein endothelial cells(HUVEC)were subjected to oxidative damage using hydrogen peroxide(H2O2)as a model.Different concentrations of S1P were applied to the oxidative damaged HUVEC.Addi-tionally,the S1PR1 agonist SEW2871,the S1PR1 inhibitor W146,and the Pyk2 inhibitor PF-562271 were used to explore the specific mechanism of S1P action.Results S1P treatment significantly alleviated oxidative damage in HUVEC and was accompanied by an increase in S1PR1 expression(P<0.05),while S1PR3 expression remained unchanged.Mean-while,the expression levels of Pyk2 and MCU decreased(P<0.05).SEW2871 further reduced mitochondrial damage,whereas W146 exacerbated it(P<0.05).Furthermore,the application of the Pyk2 inhibitor PF-562271 also reduced H2O2-induced mitochondrial damage(P<0.05),further confirming the role of Pyk2 in this process.Conclusion S1P reduces H2O2-induced mitochondrial damage and inhibits mitochondria-related apoptosis in HUVEC by suppressing Pyk2 expression via S1PR1.