Omentin-1 Modulates Porcine Endometrial Steroidogenesis and Tissue Remodelling During Early Pregnancy and the Oestrous Cycle.

In pigs, the establishment of pregnancy depends on tightly coordinated molecular interactions between the conceptus and the maternal endometrium during the peri-implantation period. Adipokines, peptide hormones produced by adipose tissue, function as endocrine mediators linking metabolic status with uterine function. Omentin-1, a hormone belonging to the adipokines group, is hypothesized to play a potential role in regulating female reproductive functions through its influence on uterine functions. Therefore, this study investigated the effects of omentin-1 on endometrial progesterone and oestradiol secretion using radioimmunoassay, on the abundance of key steroidogenic proteins and Akt phosphorylation using Western blot, and on endometrial cell proliferation and apoptosis using flow cytometry. Results showed that its actions are characterised by promotion of progesterone-dominant conditions, selective modulation of steroidogenic pathways, activation of Akt signalling, and cell-type-specific regulation of proliferation and apoptosis. This combination of effects positions omentin-1 as a previously unrecognised regulator of endometrial adaptation and suggests that adipokines may represent an important mechanistic link between metabolic status and reproductive success.