Protective effect of estrogen on mouse cerebral microvascular endothelial cells after homocysteine injury

Yu Yahuan; Gao Wen; Wang Juan

doi:10.3969/j.issn.1009-0126.2024.06.023

Abstract：Objective To investigate the effect of estrogen on the expression of matrix metallopro-teinase protein 9 and 2(MMP-9,MMP-2)and tight junction protein Occludin in mouse brain mi-crovascular endothelium cell line bEnd.3 injured by homocysteine(Hcy),and explore the protec-tive effects and underlying mechanisms of estrogen on small cerebral vascular diseases.Methods bEnd.3 cells were treated with Hcy andβ-estradiol respectively,and the optimal concentration was determined for cell proliferation and toxicity with enhanced cell counting kit-8.The cells were divided into control group,Hcy group(200 μmol/L),E2β group(200 nmol/L)and combined treatment group(200 nmol/L E2β treatment for 30 min followed by 200 μmol/L Hcy).After 6 h corresponding treatment,Western blotting was used to detect the protein levels of MMP-9,MMP-2 and Occludin in each group of cells.Results There were no significant differences in the protein levels of MMP-9,MMP-2 and Occludin in above groups after treatment for 24 and 48 h(P＞0.05).Compared with the control group,the expression levels of MMP-9 and MMP-2 was signifi-cantly increased in the Hcy Group after treatment of 72 h(1.45±0.14 vs 1.00±0.00,1.35±0.15 vs 1.00±0.00,P＜0.05),while the level of Occludin was obviously decreased(0.64±0.05 vs 1.00±0.00,P＜0.05).Compared in the Hcy Group,the MMP-9 and MMP-2 levels were obviously decreased(0.84±0.19 vs 1.45±0.14,1.01±0.78 vs 1.35±0.15,P＜0.05),and that of Occludin was notably elevated in the combined treatment group(0.91±0.10 vs 0.64±0.05,P＜0.05).Con-clusion E2β can ameliorate blood-brain barrier damage in Hcy-treated bEnd.3 cells,resulting in decreased MMP-9 and MMP-2 expressions and increased Occludin expression.