Asprosin modulates female reproductive functions in teleosts: An in vitro study in Channa punctata

Asprosin regulates various aspects of physiology in mammals including reproduction. It is reported to profoundly affect both male and female reproductive functions including gametogenesis and steroidogenesis. Asprosin is the cleaved product of a profibrillin protein encoded by the fbn1 gene. For the first time in non-mammalian vertebrates, our group demonstrated the ubiquitous expression of fbn1 and characterized asprosin protein in silico in teleost Channa punctata commonly known as spotted snakehead (ss). Based on the prominent expression of the fbn1 gene and the reproductive phase-dependent temporal expression of fbn1 in the ovary of C. punctata, we hypothesized the regulatory role of asprosin in female reproduction similar to that reported in mammals. In vitro studies confirmed the effect of asprosin on the oogenesis and steroidogenesis in C. punctata. Asprosin significantly enhanced the expression of genes crucial for oogenesis such as pcna and gdf9. It also increased the transcription of gonadotropin receptors and sex steroid receptor genes. In addition to this, asprosin accentuated the expression of steroidogenic markers such as star and cyp17a1 along with 17α, 20β dihydroxy-progesterone levels. We also measured the levels of the second messenger cAMP in ovaries exposed to asprosin to explore the probability of GPCRs as asprosin receptors. However, asprosin could not alter the cAMP levels indicating that, in the ovary of teleosts, receptors other than GPCRs might be involved in transducing asprosin action. Thus, the present study in elucidates the important role of asprosin in modulating the ovarian functions in C. punctata.