Ovarian follicular cells - living in the shadow of stemness cellular competence

Abstract

Abstract Granulosa cells (GCs) are a major component found in ovarian follicular fluid among oocytes, theca cells, and ovarian surface epithelial (OSE) cells. GCs are steroidogenic and have morphological functions that are important for the development of the follicular follicle. The follicle protects the developing female egg. GCs are also essential for the maturation of the female germ cell. Stem cell properties have been found in luteinised GCs and in vivo cultures have the potential to differentiate to become cells found outside of the ovary. Both three-dimensional (3D) culturing and mouse embryonic fibroblast (MEF) medium have been used to help improve the culturing lifespan of GCs so that their profound proliferation and differentiation capabilities can be studied. Small RNAs called MicroRNAs (miRNAs) are released from exosomes originating from GCs, and they are involved in transforming growth factor (TGF)-β signalling, follicle-stimulating hormone, hormone-related miRNAs, and apoptosis-related pathway. Finding the miRNAs involved in these pathways, and the mechanisms controlling GCs are important to treating conditions like polycystic ovary syndrome (PCOS), and creating new drug therapies. Besides GCs, ovarian stem cells (OSCs) were discovered in the OSE, and they are believed to be derived from very small embryonic stem cells (VSELs). Transplanting blood mononuclear cells, cell Hormone Therapy (cHT) with bone marrow stem cell supplement and increasing vitamin C levels are all therapies currently being researched into that involve GCs to combat the effects of aging and infertility. Running title: Stemness of ovarian follicular cells