Transcriptomic Profile of Genes Regulating Cellular Response to Extra- and Intracellular Stimuli in Porcine Ovarian Granulosa Cells During In Vitro Cultivation.

Granulosa cells (GCs), an element of the ovarian follicle, are crucial for oocyte maturation, folliculogenesis, and steroidogenesis. Granulosa cells play a crucial role in fertilization by providing metabolic and hormonal support to the oocyte, maintaining its quality and regulating its meiotic arrest. Oocyte quality and fertilization efficiency depend on the proper activity of GCs, especially their mutual communication, providing metabolic support and protecting against oxidative stress. When interrupted, they may take part in the pathogenesis of polycystic ovary syndrome, premature ovarian failure, primary ovarian insufficiency, and diminished ovarian reserve. GCs are enclosed in the antrum where they communicate with surrounding cells, create a dynamic microenvironment, and regulate hormone biosynthesis. To analyze molecular mechanisms regulating endogenous signaling, it is important to consider the dynamic transcriptomic response of porcine GCs during in vitro culturing over 48, 96, and 144 h. Transcriptomic analysis revealed a variable and dynamic transcriptional upregulation of genes associated with cellular response to endogenous and external stimuli, chemical compound metabolism, vascular development, and GCs migration. Also, proven by Gene Ontology (GO) enrichment analysis, the following terms were highlighted: "cellular response to chemical stimulus" and "cellular response to organic substance". Specific genes, such as HSD3B1, POSTN, LOX, SERPINB2, ITGB3, ANKRD1, SLC1A1, and SFRP2, exhibited significant expression changes, suggesting extensive GCs self-regulation and metabolism changes. Further analysis indicates improvements in cellular response to a cytokine stimulus, growth factor response, hormone response, enzyme-linked receptor protein signaling, and positive regulation of cell migration. These findings suggest interweaving of regulatory mechanisms underlying intercellular communication in GCs during in vitro culturing, despite the lack of signals from the native ovarian environment. Further investigating interplays of detecting pathways will provide a more comprehensive understanding and even insights into the potential clinical use of the knowledge about the role of GCs in folliculogenesis, oocyte maturation and ovulation.