Metabolic features of polycystic ovary syndrome are found in adolescent girls with hyperandrogenism.
Recently, we reported that hyperandrogenism in adolescent girls is accompanied by augmented LH pulsatility and elevated LH/FSH ratio with increased ovarian volume. Together with higher concentrations of 17-hydroxyprogesterone, androstenedione, testosterone, and estrone that are ovarian in origin, these neuroendocrine features are identical to those seen in adult women with polycystic ovary syndrome. In the present study, we report the metabolic characteristics of these hyperandrogenic adolescent girls. The GH insulin-like growth factor I (IGF-I)-binding protein (BP)-3 axis, insulin sensitivity, and insulin-IGFBP-1/insulin sex hormone binding globulin axes were evaluated in 13 adolescent girls (ages 11-18 yr) with mild to moderate signs of hyperandrogenism (HA) and 28 age-matched normal girls. Insulin sensitivity was assessed by a frequent-sample iv glucose tolerance test (ivGTT, 0.3 g/kg). Twenty-four hour blood samples were obtained at 10-min intervals and were used to determine GH pulsatility (20-min samples), IGFBP-3 levels (0800-0900 h), and fluctuations of insulin, IGFBP-1, and IGF-I (hourly samples) during feeding and fasting phases of the day. In addition, GH responses to GHRH stimulation (1 microgram/kg) were assessed. Fasting insulin concentrations, but not plasma glucose levels, were significantly elevated in the HA group compared with those in the normal group (256 +/- 35 vs. 103 +/- 24 pmol/L, P = 0.0008), as were insulin responses to ivGTT and meals (P < 0.01) and 24-h mean insulin concentrations (P < 0.01). Thus, hyperinsulinemia with normal fasting glucose levels in HA girls may reflect insulin resistance, as suggested by the increased ratio of insulin and glucose (P < 0.001). All measures of insulin were correlated with body mass index (BMI); however, insulin remained significantly higher in the HA group after correcting for BMI, suggesting that decreased insulin sensitivity was related to other factors in addition to BMI. Twenty-four hour IGFBP-1 concentrations showed a diurnal pattern with an inverse relationship to insulin, and 24-h mean concentrations were lower in the HA group (0.35 +/- 0.13 vs. 0.76 +/- 0.09 micrograms/L, P = 0.02). Reduced sex hormone binding globulin levels were also inversely related to insulin levels (P = 0.0007). In contrast, GH pulsatile characteristics and IGF-I/IGFBP-3 levels, as well as GH responses to GHRH, were similar between the groups.(ABSTRACT TRUNCATED AT 400 WORDS)
Apter
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D
Department of Reproductive Medicine, School of Medicine (0633), University of California San Diego, La Jolla 92093-0633, USA.
Bützow
T
T
Laughlin
G A
GA
Yen
S S
SS
D019326:17-alpha-Hydroxyprogesterone; D000293:Adolescent; D000328:Adult; D000728:Androgens / Q000097:blood*; D000735:Androstenedione / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D002648:Child; D004970:Estrone / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D005951:Glucose Tolerance Test; D013006:Growth Hormone / Q000097:blood / Q000378:metabolism; D006628:Hirsutism; D006801:Humans; D006908:Hydroxyprogesterones / Q000097:blood; D007328:Insulin / Q000097:blood; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000097:blood; D007986:Luteinizing Hormone / Q000097:blood / Q000378:metabolism; D008572:Menarche; D008598:Menstruation; D009839:Oligomenorrhea; D010053:Ovary / Q000503:physiopathology; D011085:Polycystic Ovary Syndrome / Q000097:blood / Q000378:metabolism* / Q000503:physiopathology; D012044:Regression Analysis; D012738:Sex Hormone-Binding Globulin / Q000032:analysis; D013739:Testosterone / Q000097:blood
D000728:Androgens; D001786:Blood Glucose; D006908:Hydroxyprogesterones; D007328:Insulin; D018970:Insulin-Like Growth Factor Binding Protein 1; D012738:Sex Hormone-Binding Globulin; D004970:Estrone; D013739:Testosterone; D000735:Androstenedione; D019326:17-alpha-Hydroxyprogesterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D013006:Growth Hormone