The Effect Of Angiotensin Ii Receptor Type 1 Autoantibodies On Fetal Rats' Cardiac Hypertrophy And Underlying Mechanisms

Objectives: Endothelial senescence has been proposed to be involved in endothelial dysfunction and atherogenesis. This study investigates the effects of ginsenoside Rb1, a major constituent of ginseng, on H2O2-induced endothelial senescence. And here we have investigated the expression and production of caveolin-1, a protein that has been shown previously to be upregulated in stress-induced premature senescence. Methods: Primary human umbilical vein endothelial cells (HUVECs) senescence was induced by H2O2 as judged by senescence-associated b-galactosidase assay (SAb-gal). Caveolin-1 mRNA expression was analyzed by real time PCR. Caveolin-1 protein expression was determined by Western blot and laser scanning confocal microscopelaser scanning confocal microscopy. Results: Treatment of HUVECs with 60mM H2O2 induced premature senescence. Pretreatment of HUVEC with Rb1 was found to reverse endothelial senescence, as witnessed by a significant decrease of senescent cell numbers (approximately 2-fold reduction). Rb1 could markedly decrease Caveolin-1 mRNA expression compared with cells treated with H2O2 alone. Meanwhile, Caveolin-1 protein expression decreased in the 20mM Rb1-pretreated cells compared to that in cells treated with H2O2 alone. By laser scanning confocal microscopy, we also found that Rb1 can effectively decrease Caveolin-1 protein expression. Conclusions: Our report demonstrates that Rb1 can exert reversal effects on H2O2induced cellular senescence through modulating Caveolin-1 expression.