Insulin-Like Growth Factor-II and Insulin-Like Growth Factor Binding Proteins in Bovine Cystic Ovarian Disease

REY F; RODRÍGUEZ F; SALVETTI N; PALOMAR MM; BARBEITO CG; ALFARO NS; ORTEGA HH

JOURNAL OF COMPARATIVE PATHOLOGY

Elsevier

Lugar: Bristol UK ; Año: 2010 vol. 142: p. 193 - 204

0021-9975

Cystic ovarian disease (COD) is one of the most common reproductive disorders of cattle and is considered tohave multifactorial aetiology. An accepted hypothesis involves neuroendocrinological dysfunction of the hypothalamic-pituitary-gonadalaxis; however, the role of growth factors and COD has not been extensively investigated.The present study examines the potential role of members of the insulin-like growth factor (IGF)family in COD. Expression of genes encoding IGF-II and insulin-like growth factor-binding proteins (IGFBPs)was examined and the distribution of IGF-II within the follicular wall was assessed immunohistochemically.Finally, the concentration of IGF-II protein was determined in follicular fluid. There was increased IGF-II mRNA in the wall of cystic follicles, mainly associated with granulosa cells. Additionally, there was significantly more IGF-II protein in granulosa and theca cells in cystic follicles, but no change in the concentration of IGF-II in follicular fluid. Total IGFBPs, assessed by western blotting, were similar in different structures.However, by discriminating each IGFBP a decrease was detected in IGFBP-2 expression in cystic follicles that may be related to the observed higher expression of IGF-II. In summary, the present study provides evidence to suggest that COD in cattle is associated with modifications in the IGF-II system