Alterations in the insulin pathway in the ovary of cows with induced follicular persistence.

GAREIS NC; STASSI AF; RODRÍGUEZ FM; CATTANEO MOREYRA ML; SALVETTI NR; ORTEGA HH; HEIN GJ; REY F

Mar del Plata

Congreso; LXII Reunión anual de la Sociedad Argentina de Investigación Clínica (SAIC); 2018

Severallocal factors, including components of the insulin pathway, are involved in theovarian follicular persistence associated with anovulation. In previousstudies, we detected alterations of insulin-signaling intermediaries in theovaries from cows with cystic ovarian disease. Therefore, we aimed to study theprotein expression of IR, IRS1, PI3K, total and phosphorylated AKT byimmunohistochemistry in ovarian follicular structures from a model offollicular persistence. We also measured the insulin concentrations in serumand follicular fluid by radioimmunoassay. The model was performed with anintravaginal progesterone device to get subluteal concentrations ofprogesterone, obtaining dominant follicles in the expected day of ovulation (n=5;P0) and follicles that persist for 5 (n=5; P 5), 10 (n=5; P10) or 15 days (n=5;P15) relative to the expected time of ovulation. Controls cows wereovariectomized in proestrus (n=5; C). Serum insulin concentrations were higherin all persistence groups than in control cows and the intrafollicularconcentrations were higher in P5, P10 and P15 groups respect to the controlgroup (p<0.05). In granulosa cells, the expression of IR was higher indominant follicles of control group relative to all persistent folliclesevaluated (p<0.05). In theca cells, the expression of IR was higher in persistentfollicles of P0 and P5 groups respect to persistent follicles of P10 and P15 groups(p<0.05). While in granulosa, the IRS1 was higher in the dominant folliclesthan in persistent follicles of P5 and P15 groups (p<0.05), the expressionin theca cells showed no differences (p>0.05). The PI3K and phosphorylatedAKT were higher in control group than all persistence groups in both cellpopulations (p<0.05). Total AKT expression showed no differences(p>0.05). Alterations of the insulin-signaling in follicular persistencecould be involved in a lower insulin response that might be associated withdisorders in ovarian functionality.