Tannic Acid Regulates Autophagy in the Ovary of Female Brandt’s Voles Affecting their Reproduction

Tannic acid, as a polyphenol, is widely present in dicotyledonous plants and angiosperms. The study found that tannins could affect the ovarian development of Brandt’s voles. However, the specific effects of tannic acid on reproduction and its underlying mechanisms are still poorly understood. Therefore, this study explored the effects of tannic acid on the reproduction of Brandt’s voles. We treated female Brandt’s voles from four weeks postpartum with varying tannic acid doses (0 (control), 0.3% (low dose) or 0.6% (high dose) tannic acids) until 8 weeks (puberty) and 13 weeks (sexual maturity)). Ovarian specimens were collected for immunohistochemical analysis and RT-PCR. The treated Brandt’s voles were mated with male Brandt’s voles of the same age and we recorded the number of embryos, litters and the male to female ratio of the offspring. We found that the female Brandt’s voles in the low-dose tannic acid group had enhanced reproductive abilities, characterized by reduced follicular atresia and increased numbers of embryos and litters of offspring. The different doses of tannic acid altered the female-male ratio of the Brandt’s voles’ offspring. While the low-dose of tannic acid enhanced the level of ovarian autophagy by significantly increasing the expression of Beclin1 and LC3 proteins in the ovaries of the Brandt’s voles during sexual maturity. In short, tannic acid can promote the reproduction of Brandt’s voles by affecting the level of ovarian autophagy and improving the development of follicles. Tannins can boost the reproduction of Brandt’s voles.