The positive influence of leptin in mature corpus luteum function of pregnant sows

Abstract

Abstract Background: Leptin, well-known modulator of fat deposition and energy metabolism, is a rather peptide hormone involved in reproduction. The mature corpus luteum (CL) of pregnant pig is able to undergo luteolysis in response to prostaglandin (PG)F2α, luteolytic capacity is established. However, the direct role of leptin in mature CL functin of pregnant sows has remained obscure, especially in PGF2α-reduced CL function. Methods: We first investigated the expressions of leptin and its long form receptor (Ob-R) in the mature CL and cultured luteal cells of pregnant sows. We therefore used luteal cells of mature CL of pregnant sows to investigate the effect of leptin on CL function. Results: Our results showed that leptin and Ob-R immunostaining was predominantly located in luteal cells of mature CL, and leptin and Ob-R proteins were detected in cultured luteal cells. In vitro, treatments of luteal cells with PGF2α are decreased cell viability and P4 release. To note, leptin is increased the basal and PGF2α-reduced cell viability, and P4 release by luteal cells. Leptin is also accelerated the LH-stimulated P4 secretion in luteal cells. Furthermore, leptin is induced PGE2 release, but reduced PGF2α secretion by luteal cells. Finally, leptin is increased the release and mRNA expression of LH by luteal cells. Conclusions: Our data provide evidence for the expressions of leptin and Ob-R in the mature CL and cultured luteal cells, and a positive influence of leptin in mature CL function of pregnant sows. The findings may represent an additional link between energy metabolism and pregnant female reproduction.