Hydroxysafflor yellow a promotes angiogenesis in rat brain microvascu-lar endothelial cells injured by oxygen-glucose deprivation/reoxygena-tion(OGD/R) through SIRT1-HIF-1α-VEGFA signaling pathway

Objective: Angiogenesis led by brain microvascular endothelial cells (BMECs) con-tributes to the remission of brain injury after brain ischemia reperfusion. In this study, we investigated the effects of hydroxysafflor yellow A(HSYA) on angiogenesis of BMECs injured by OGD/R via SIRT1-HIF-1α-VEGFA signaling pathway. Methods: The OGD/R model of BMECs was established in vitro by OGD for 2h and reoxygena-tion for 24h. At first, the concentrations of vascular endothelial growth factor (VEGF), Angiopoi-etin (ang) and platelet-derived growth factor (PDGF) in supernatant were detected by ELISA, and the proteins expression of VEGFA, Ang-2 and PDGFB in BMECs were tested by western blot; the proliferation, adhesion, migration (scratch healing and transwell) and tube formation experiment of BMECs; the expression of CD31 and CD34 were tested by immunofluorescence staining. The levels of sirtuin1(SIRT1), hypoxia-inducible factor-1α (HIF-1α), VEGFA mRNA and protein were tested. Results: HSYA up-regulated the levels of VEGF, Ang and PDGF in the supernatant of BMECs un-der OGD/R, and the protein expression of VEGFA, Ang-2 and PDGFB was increased; HSYA could significantly alleviate the decrease of cell proliferation, adhesion, migration and tube formation ability of BMECs during OGD/R; HSYA enhanced the fluorescence intensity of CD31 and CD34 of BMECs during OGD/R; HSYA remarkably up-regulated the expression of SIRT1, HIF-1α, VEGFA mRNA and protein after OGD/R, and these increase decreased after SIRT1 was inhibited. Conclusion: SIRT1-HIF-1α-VEGFA signaling pathway is involved in HSYA improves angiogene-sis of BMECs injured by OGD/R