Influência da adiponectina sobre a maturação de oócitos in vitro no modelo caprino

Abstract

In Brazil, goat farming is an activity in potential growth, this can be evidenced with greater intensity in the northeast region, which holds the great majority of the Brazilian goat herd. As a result, the demand for investments in this activity has been significant in recent years, thus requiring more technification to improve and expand this sector. In this sense, reproductive biotechnologies prove to be effective instruments, in which we highlight the In-vitro production of embryos (PIVE), which promotes the multiplication of higher genetics in a shorter period of time than traditional methods. However, there is still a long way to go with this technique in the caprine species, since, currently, its results in this species are still variable and limited, which implies limitation at the commercial level. Adiponectin is a protein hormone produced predominantly by adipose tissue, it may be an alternative to increase in this area. Some of its functions are related to female reproduction, as a positive influence on steroidogenesis and also on the in vitro maturation of oocytes in some species, including the goat species. This work aimed to investigate whether: 1) adiponectin influences the meiotic maturation of goat oocytes; 2) the MAPK MEK1 / 2 pathway mediates the effects of adiponectin during in vitro maturation and 3) adiponectin differentially affects the mRNA abundance of genes relevant for adiponectin signal transduction in oocytes and cumulus cells. The addition of adiponectin (5 μg / mL) during the maturation of goat oocytes affected the percentage of oocytes that successfully completed nuclear maturation (P <0.05). Adiponectin-stimulated nuclear maturation of oocytes was significantly impaired when the specific inhibitor of MEK 1/2 (U0126) was added to the maturation medium. There was no evidence of any difference induced by adiponectin in the relative abundance of the transcripts of the genes AdipoR1, AdipoR2, AMPKα1, PPARα and PPARγ. AMPKα2 expression was significantly inhibited in cumulus cells derived from cumulus-oocyte complexes matured with 5 μg / mL adiponectin compared to those matured at 0 μg / mL (P <0.05). In conclusion, adiponectin improves meiotic maturation of goat oocytes via MAPK MEK 1/2. Additionally, effects on AMPKα2 transcript levels were detected in cumulus cells but not in oocytes.