17β-Estradiol Inhibits Oxidative Damage in Cataracts Rats via NOTCH1 Signaling

Abstract

This study assesses the effect of 17β-estradiol on oxidative damage and NOTCH1 levels in cataract rats. 45 SD rats, aged 8–12 weeks old and weighted 225–312 g were assigned into healthy group, cataract group, and treatment group with n = 15 in each group followed by analysis of the pathological morphology of rat lens by HE staining, cell apoptosis by flow cytometry, and the degree of turbidity under a microscope. Meanwhile, MDA and SOD levels were measured and NOTCH1, p53 and BAX expressions was detected by PT-PCR. The Healthy group rats showed complete and orderly lens structure, whereas, the cataract group showed disorganized and distributed loosely lens, with the formation of vacuoles and the rupture and degradation of fibrocells. In the treatment group, the lens epithelial cells were orderly and evenly distributed, and the vacuoles were significantly reduced. The apoptotic rate of lens epithelial cells in healthy group (1.79±0.11)% was significantly lower than that in cataract group (15.22±1.17)% (P < 0.05), which showed significantly higher apoptotic rate than treatment group (6.31±1.12)% (P < 0.05). The degree of eye turbidity was increased in cataract group and reduced in treatment group compared with that in healthy group (P < 0.05). In addition, cataract group showed significantly reduced SOD and increased MDA level groups along with upregulated Notch1, p53 and Bax (P < 0.05). However, treatment group showed significantly increased SOD, decreased MDA and downregulated Notch1, p53 and Bax. In conclusion, 17β-estradiol reduces the apoptosis rate of lens epithelial cells in cataract rats by reducing NOTCH1 level, thereby enhancing the ability to resist oxidative damage.