Human ovarian follicular granulosa cells isolated during ART procedure reflect substantial changes in activation of hormonal signaling pathways, during long-term in vitro conditions

Abstract

The ovary is commonly known as an endocrine gland responsible for sex steroid production. One of the outstanding cells in ovarian microenvironment - granulosa cells (GCs) are responsible for converting the androgens to estrogens during follicular growth and secreting progesterone after ovulation. These secretory processes within the ovary are directly involved in hormonal signaling pathways, and they depend on different stages of cholesterol and lipid biosynthesis during the ovarian cycle. The understating of the regulation and further investigation into the processes taking part in ovary will expose new clinical advantages in detection and treatment of female reproductive system diseases associated with sex hormone abnormalities. The expression of genes belonging to ontology groups associated with steroid biosynthesis and metabolism, such as “cholesterol biosynthetic process” (GO:0006695, “regulation of lipid biosynthetic process” (GO:0046890), “regulation of lipid metabolic process” (GO:0019216), “response to insulin” (GO:0032868) and “response to lipopolysaccharide” (GO:0032496) were analyzed by using the microarray approach. The patterns of gene expression in human GCs at days 1-day, 7-day, 15-day, and 30-day of primary in vitro culture have been analyzed. Based on the microarray results, a group of upregulated genes have been selected: CCL20, CXCL5, STAR, MSMO1, and AADAC. The genes STAT5B, OPA3, PPARG, PROX1, and SEC14L2 were decreased across all the experimental groups during the 30-day cell cultivation period. These results suggest that, the GCs in cell culture under in vitro express steroidogenic markers and it is important to understand associations with lipid and liposaccharide synthesis relative to reproductive medicine.