Expression of matrix metalloproteinase 2 (MMP2) in the ovary in a bovine stress model

BELOTTI EM; STASSI AF; VELÁZQUEZ MM; MATILLER V; REY F; ORTEGA HH; SALVETTI NR; PERREN L

Mar del Plata

Congreso; Reunión anual de SAIC, SAI, SAFE; 2016

Dairy cattle are daily subjected to stressful situations some of which can be associated to reproductive problems. Under these conditions, the microenvironment of the ovary is modified, affecting directly normal follicular remodeling, necessary to ovulation. The aim of this study was to evaluate the matrix metalloproteinase 2 expression, enzyme that is involved in follicular wall tissue remodelling during ovulation process. MMP2 expression was evaluated by immunohistochemistry on ovarian samples of cows treated with adreconcorticotropin (ACTH) every 12 hours, for four days before ovulation time. Primary, small preantral, large preantral, antral, atretic and preovulatory follicles oftreated animals (n=5) and control group (n=4) were evaluated. We detected that granulosa cells of preovulatory follicles of ACTH treated group presented higher expression than those of antral follicles of control group (p<0.05). Moreover, the theca interna cells of these preovulatory follicles showed atendency to higher expression compared to the theca interna cells from antral follicles of control group (p<0.09). In large preantral and atretic follicles from treated group, we detected a tendency to increase the MMP2 expression in relation to control animals (p=0.09). These results might indicate that exist an increase of MMP2 expression in preovulatory follicles of ACTH treated group that could affect the follicular remodeling changes of preovulatory phase. Follicular wall degradation process (one of most important MMP2 roles), raised as a focal acute inflammatory response, depends on an equilibrated and complex mechanism, that could be affected by tissue metalloproteinases and their inhibitors.