Heat shock protein patterns in the bovine ovary and their relation with cystic ovarian disease

VELÁZQUEZ MML; ALFARO NS; DUPUY C; SALVETTI NR; REY F; ORTEGA HH

ANIMAL REPRODUCTION SCIENCE

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2010 vol. 118 p. 201 - 209

0378-4320

The present study was performed to determine how the development of Cystic Ovarian Disease (COD) affects the ovarian expression of Heat Shock Proteins (HSPs) in cycling cows. HSP27, HSP60, HSP70 and HSP90 were evaluated in different ovarian components by western blot and semiquantitative immunohistochemical analysis. Higher expression of HSP27 was detected in the granulosa and theca of primary, secondary, tertiary and cystic follicles, with decreasing levels in atretic follicles. HSP60, 70 and 90 showed a similar pattern of immunostaining, with moderate expression in primary and secondary follicles, increased expression in tertiary and atretic and follicles and the highest levels of expression in cystic follicles. HSPs were also localized in the corpus luteum, corpus albicans, interstitial tissue and tunica albuginea. The relative protein expression in the follicular wall of small and large healthy follicles and cystic follicles as analysed by western immunoblot was consistent with the immunohistochemical data. We speculate that altered expression of HSPs decreases apoptosis in the follicular wall and leads to the delayed regression of cystic follicles.  This study supports earlier observations suggesting that aberrant HSP expression, observed in cells of the cystic follicles, is probably associated with the intra-ovarian component of COD pathogenesis.