Abstract: During the menstrual cycle, the ovarian function is maintained by a series of local growth factors and cytokines. Activin, an important member of the transforming growth factor-β (TGF-β) super family, is mostly produced by granulosa cells in the ovarian. Activin exerts its biological functions through the activin receptor-like kinase that activates SMAD signaling pathways or non-SMAD pathways. Activin plays an critical role in regulating ovarian functions through paracrine/autocrine signaling, including granulosa cells proliferation, follicular development and steroidogenesis. Besides, activin is associated with ovarian diseases. Abnormal expression of activins and their subunits was detected in ovarian cancer tissues which was implicated in the development of ovarian cancer. In addition, the imbalance between activins and their endogenous inhibitors may play an important part in the pathology of polycystic ovary syndrome (PCOS) and follicular dysplasia. This review summarized the regulatory effect of activins in ovarian function and related diseases.

Key words: Activins, Ovary, Ovarian follicle, Ovarian neoplasms, Polycystic ovary syndrome