Insulin-like growth factor binding proteins in a natural pre-ovulatory follicle from a woman with polycystic ovary syndrome.
Insulin-like growth factor binding protein (IGFBP) concentrations in the follicular fluid of ovarian follicles have been shown to correlate with dominance and atresia. IGFBP-2 and IGFBP-4 are increased in atresia, and IGFBP-3 is decreased in dominant follicles. The purpose of this study was to compare the IGFBP concentration in follicular fluid from a natural pre-ovulatory follicle of a woman with polycystic ovarian syndrome (PCOS) with other PCOS follicles and dominant follicles from normally cycling women. Follicular fluid was collected from 5-7 mm diameter follicles and a natural pre-ovulatory follicle from women with PCOS, and healthy and atretic follicles from normal women. The IGFBP profiles were analysed using Western ligand blotting. The IGFBP concentrations in the 5-7 mm diameter follicles from the polycystic ovaries containing a pre-ovulatory follicle were similar to those in follicles from other women with PCOS, and comparable with androgenic cohort follicles from normal women. In particular, the IGFBP-2 and IGFBP-4 concentrations were elevated significantly compared with the oestrogenic cohort follicles. The concentrations of all IGFBP detected in the follicular fluid from the PCOS pre-ovulatory follicle were significantly less than those of the 5-7 mm diameter follicles from the same subject. The IGFBP concentrations were within the range of normal dominant follicles, and IGFBP-2 and IGFBP-3 were at the lower end of the normal range. The results indicate that the PCOS pre-ovulatory follicle contained a normal pattern of IGFBP expression even though the other follicles exhibited a pattern typical of PCOS. These data support the hypothesis that decreased concentrations of IGFBP, in particular IGFBP-3, may be involved in selection of the dominant follicle, and that when a spontaneous pre-ovulatory follicle develops in PCOS, the underlying cause of the polycystic ovaries is not resolved but the rest of the ovary remains polycystic.
Magoffin
D A
DA
Department of Obstetrics and Gynecology, Cedars-Sinai Research Institute, Cedars-Sinai Medical Center/UCLA School of Medicine 90048, USA.
San Roman
G A
GA
Muderspach
L I
LI
D000328:Adult; D004958:Estradiol / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D015571:Follicular Fluid / Q000737:chemistry*; D006801:Humans; D018971:Insulin-Like Growth Factor Binding Protein 2 / Q000378:metabolism; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000378:metabolism; D018974:Insulin-Like Growth Factor Binding Protein 4 / Q000378:metabolism; D018969:Insulin-Like Growth Factor Binding Proteins / Q000032:analysis*; D007986:Luteinizing Hormone / Q000097:blood; D011085:Polycystic Ovary Syndrome / Q000378:metabolism*; D011374:Progesterone / Q000097:blood
D018971:Insulin-Like Growth Factor Binding Protein 2; D018972:Insulin-Like Growth Factor Binding Protein 3; D018974:Insulin-Like Growth Factor Binding Protein 4; D018969:Insulin-Like Growth Factor Binding Proteins; D011374:Progesterone; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone