Neuromedin B regulates porcine granulosa cell proliferation, apoptosis, and steroidogenesis via NMBR

Ovarian follicular development is a complex process critically dependent on the precise regulation of granulosa cell (GC) proliferation, apoptosis, and steroidogenesis. Dysregulation in these processes can lead to infertility or ovarian disorders. While various local regulatory peptides are known to influence female reproductive physiology, the specific role of Neuromedin B (NMB), a bombesin-like peptide, in porcine ovarian GCs has been largely unexplored. Understanding NMB's influence on GC function could reveal novel neuroendocrine mechanisms governing follicular maturation and provide targets for improving reproductive outcomes in livestock.

In an in vitro study, researchers investigated Neuromedin B's effects on porcine ovarian granulosa cells. They first mapped NMBR distribution, noting higher expression in larger follicles. Granulosa cells were then treated with various concentrations of NMB. To confirm NMBR involvement, the selective NMBR antagonist PD168368 was co-administered. Endpoints included cell viability, apoptosis rates, and steroidogenesis (E2 production), assessed via ELISA for hormones and qPCR/Western blot for gene/protein expression of proliferation (Cyclin B1, PCNA), apoptosis (Bax, Bcl-2, Caspase-3), and steroidogenic enzymes (STAR, CYP11A1, HSD3B1, CYP19A1).