[Effect of SIRT1 on delay of D-gal-induced premature ovarian failure in mice with ginsenoside Rg_1]

To explore the effect of slient mating type information regulation 2 homolog 1(SIRT1) on the delay of D-galactose(D-gal) induced premature ovarian failure in mice with ginsenoside Rg_1(Rg_1). Fifty-four female SPF BALB/c mice were randomly divided into PBS group, D-gal group, and Rg_1 group. In the D-gal group, D-galactose(200 mg·kg~(-1)·d~(-1)) was injected subcutaneously into the neck and back for 42 days. In the PBS group, the equal amount of phosphate buffered saline(PBS) was injected into the neck and back for 42 days. In addition to the therapy of D-gal group, Rg_1 group was given Rg_1(20 mg·kg~(-1)·d~(-1)) through the intraperitoneal injection on the 15 th day for 28 days. At the same time, the D-gal group and the PBS group were also given an equal amount of PBS through hintraperitoneal injection on the 15 th day for 28 days. The changes in body weight and ovarian weight coefficient of mice were detected. Expressions of estradiol 2(E_2), luteinizing hormone(LH), superoxide dismutase(SOD), catalase(CAT) and follicle-stimulating hormone(FSH) in peripheral blood were detected. Morphological changes of ovaries were detected by HE staining. Changes in expression of aging regulator SIRT1 were detected by fluorescent quantitative PCR and Western blot. The results showed that compared with the PBS group, the body weight growth rate of the D-gal group was significantly slowed, the ovarian weight coefficient was decreased, the serum levels of E_2, LH, SOD, CAT were significantly reduced, and FSH was significantly increased. After the administration with Rg_1, the body weight growth rate, ovarian weight coefficient, serum levels of E_2, LH, SOD, and CAT in the mice were higher than those in the D-gal group, while FSH was lower than those in the D-gal group. HE staining showed that the follicular morphology and structure of the PBS group were normal; the number of follicles in the D-gal group was reduced, the corpus luteum was vacuolated, and the number of atretic follicles was increased. Compared with the D-gal group, the number of follicles in the Rg_1 group was increased, whereas the number of corpus luteum was decreased. Compared with the PBS group, SIRT1 expression was down-regulated in the D-gal group, while SIRT1 expression was up-regulated in the Rg_1 group compared with the D-gal group. The results suggested that Rg_1 could delay D-gal-induced premature ovarian failure in a mouse model of premature ovarian failure, and SIRT1 played an important role in this.