Selected molecular and physiological aspects of mammalian ovarian granulosa cells in primary culture

The ovary is a complex endocrine gland that is responsible for sex steroid production in mammals. The basic functional unit of the ovary is the follicle, which contains the oocyte (OC), and surrounding cells, including granulosa cells (GCs) and theca cells, which support OC development. The process of formation and development of a follicle is known as folliculogenesis, during which the proliferation and differentiation of the GCs are required for proper formation of the follicle. In this review article, we present an overview of the molecular aspects of oogenesis and folliculogenesis, with subsequent description of mammalian ovulation. Moreover, we describe how growth, proliferation, and differentiation of GCs is regulated on a molecular level across mammalian species. Based on recent scientific reports, we depict possible biomedical applications and propose directions for future research using mammalian GCs in primary culture.