Changes in the Proliferation/Apoptosis Balance in the Bovine Ovary: A Key Early Event in Follicular Persistence

BELOTTI, E.M. (EQUAL CONTRIBUTION); STASSI A.F. (EQUAL CONTRIBUTION); VELAZQUEZ M.M.L.; DÍAZ, P. U.; MARELLI, B.E.; REY, F.; NOTARO, U. S.; ORTEGA, H.H.; SALVETTI, N.R.

CELLS TISSUES ORGANS

KARGER

Lugar: Basel; Año: 2017

1422-6405

The objective of this work was to evaluate proliferation andapoptosis in the bovine ovary in a model of follicular persistenceinduced by low levels of progesterone to detect incipientchanges during cystic ovarian disease developmenton the expected day of ovulation (day 0) and after 5, 10, and15 days of follicular persistence. We analyzed cell proliferationby evaluating the expression of Ki-67 and apoptosis byevaluating caspase-3, BAX, and BCL2 expression. Proliferationwas similar in the granulosa and theca cells of antral folliclesin the P0 group (treated with progesterone up to theexpected day of ovulation) and in the control group. A decreasein cell proliferation was detected after 5 days of persistence(P5) in relation to P0 ( p < 0.05). Similar changes werefound in the granulosa cells of the persistent follicles in relationto the control group ( p < 0.05). Caspase-3 expressionwas similar in granulosa cells of antral follicles at early stagesof persistence, with an increase after 15 days of persistence( p < 0.05). In the granulosa cells of group P10 (10 days of persistence), caspase-3 expression was reduced relative to thatof antral follicles from the control group ( p < 0.05). BCL2 expressionwas higher in granulosa cells of the persistent folliclesof group P0 relative to the control follicles, with nochanges in BAX expression, which was increased in persistentfollicles of group P15 ( p < 0.05). Similar results were observedin theca cells at initial stages of persistence. The resultsshow that, initially, proliferation is maintained with lowapoptosis and an increase in cell survival.