Taurine improves follicular survival and function of mice ovarian grafts through increasing CD31 and GDF9 expression and reducing oxidative stress and apoptosis

Ischemia-reperfusion (IR) injury is a major limitation of ovarian transplantation which threatens the follicular and graft survival. Taurine as a potent anti-oxidant, anti-apoptotic and anti-inflammatory agent, can prevent graft damages due to IR. We aimed to investigate the effect of taurine on the follicular survival and function of autotransplanted mouse ovaries. Female mice (4-5 weeks old) were divided into: control, autograft and autograft + taurine (200 mg/kg/day). The level of CD31 expression was evaluated two days (48 h) post transplantation. In addition, on day 7 post transplantation the serum levels of malondialdehyde (MDA) and the total antioxidant capacity (TAC) were assessed. Also, 28 days post transplantation; ovaries were studied stereologically and the percentage of apoptotic follicles, level of GDF9 expression and the serum concentrations of progesterone and estradiol were measured. Data were analyzed using one-way ANOVA and Tukey's test and the means were considered significantly different at P < 0.05. The total volume of the ovary (P < 0.01), volume of the cortex (P < 0.01) and medulla (P < 0.04), total number of different types of follicles, expression of GDF9 and CD31 and also the levels of progesterone, estradiol and TAC increased significantly in the autograft + taurine group compared to the autograft group (P < 0.001). The MDA level and apoptosis rate decreased significantly in the autograft + taurine group compared to the autograft group (P < 0.001). Taurine could significantly improve follicular survival and the function of grafted ovaries by accelerating the angiogenesis and reducing oxidative stress and apoptosis.