GH release after GHRH plus arginine administration in obese and overweight women with polycystic ovary syndrome

Abstract

Few and unclear data are available in the literature about the relationship between impairment of GH/IGF-I axis and polycystic ovary syndrome (PCOS). This study was aimed to evaluate the basal GH and IGF- levels, and GH release after challenge test in obese and overweight women with PCOS. Thirty patients with PCOS and other 30 healthy women matched for age, body mass index (BMI) and waist-hip ratio (WHR) were studied. Serum follicle-stimulating hormone (FSH), LH, PRL, E2, P, 17OH-progesterone (17OH-P), total T, delta4, DHEA-S, SHBG, GH and IGF-I levels were evaluated in each subject. A GHRH plus arginine challenge test was performed in all subjects. After provocative test, in PCOS and control women the GH levels were significantly (p<0.05) higher in comparison to basal values from 30 min to 120 min. At the same times, a significant (p<0.05) difference was observed between women with PCOS in comparison to healthy women. The mean peak value of GH resulted significantly (p<0.05) lower in PCOS women in comparison to healthy women. The total GH response (area under curve, AUC) to GHRH plus arginine test resulted significantly (p<0.05) lower in PCOS than in healthy women. These findings were statistically significant (p<0.05) also considering the distinction in obese and overweight women. The AUC for GH secretion was significantly lower (p<0.05) in obese in comparison to overweight subjects in the control group, whereas no significant difference was detected between obese and overweight women in the PCOS group. In conclusion, in PCOS women there is a BMI-independent alteration of the GH levels. Further investigations will be necessary to establish the real cause of these data.

Pioglitazone Treatment Increases Spontaneous Growth Hormone (GH) Secretion and Stimulated GH Levels in Polycystic Ovary Syndrome

“…High insulin levels have been shown to decrease levels of IGFBP-1, and this may elevate serum levels of free IGF-I and subsequently inhibit the secretion of GH through increased IGF-I feedback on the pituitary (17). In agreement with this hypothesis, several studies found significantly higher levels of serum total IGF-I in PCOS patients, compared with weight-matched controls (5,(42)(43)(44); however, other studies were not able to reproduce this. As recently reviewed by Frystyk (17), measurement of free IGF-I may be a better indicator of the GH secretion in conditions with an abnormal insulin sensitivity.…”

Administration of exogenous ghrelin in obese patients with polycystic ovary syndrome: effects on plasma levels of growth hormone, glucose, and insulin

“…A significantly lower GH response to exercise was demonstrated in patients with PCOS, with a negative correlation between GH response and BMI (34). Both the mean peak value of GH and the total GH response to GHRH plus arginine were found to be significantly lower in obese patients with PCOS than in healthy obese women (35). Obese women with PCOS show a markedly decreased GH response to the administration of GHRH (14) in basal conditions.…”