In vitro effect of omentin-1 on level of other adipokines in granulosa cells from ovaries of Large White and Meishan pigs.

Omentin-1, also known as intelectin-1 (ITLN1), is an adipokine produced by visceral adipose tissue and effect on improve insulin sensitivity, regulate energy metabolism and reproduction. Our previously data has shown that ITLN1 expression in porcine ovarian follicles is influenced by both the level of adiposity and the phase of the estrous cycle. Additionally, recent studies have indicated variations in the serum levels of adipokines in pigs with higher fat content, suggest their common interaction. It was therefore hypothesized that ITLN1 regulates the levels of other adipokines and their receptors in the ovary of pigs with different fat content. The aim of this study was to investigate the in vitro effect of ITLN1 (10-100 ng/mL) on the levels of other adipokines, namely adiponectin, apelin, leptin, chemerin, resistin, visfatin, and vaspin in the culture medium, assessed by ELISA. In addition, the effect of ITLN1 on the mRNA expression of the above-mentioned adipokines with their receptors was investigated using RT-qPCR in granulosa cells (Gc) from normal weight Large White (LW) and fat Meishan (MS) pigs on days 10-12 of the estrous cycle. The results showed that ITLN1 reduced apelin levels, increased leptin, and had no effect on vaspin in the culture medium. ITLN1 was found to have a modulating effect on the mRNA expression of the other adipokines with their receptors in porcine Gc. It can, therefore, be proposed that ITLN1 represents a previously unidentified auto- and paracrine regulator of the functions of ovarian microenvironmental compartments in different types of pig breeds.