Elevated Ghrelin Plasma Levels in Patients with Polycystic Ovary Syndrome

Abstract

Polycystic ovary syndrome is a common endocrine disorder in women. It is associated with hirsuitism, obesity, insulin resistance, abnormality in the growth hormone/insulin-like growth factor I (IGF-1) axis and polycystic ovaries. The etiology of PCOS has not been clarified. Ghrelin is an endogenous ligand of the growth hormone secretagogue receptor. It is mainly secreted by stomach cells but has also been shown to be present in hypothalamus, pituitary, pancreas and gonads. Ghrelin is a regulator of energy homeostasis and GH secretion. The influence of ghrelin on insulin secretion and gonadal function is known. Since ghrelin may play an important role in pathophysiology of PCOS, we studied ghrelin levels in a group of 52 women with PCOS and in 16 women in a control group. Plasma levels of insulin, total testosterone, SHBG, LH, and FSH were also measured. In conclusion, PCOS women have higher ghrelin levels than controls. Ghrelin negatively correlates with BMI and insulin levels in PCOS group. A relation between ghrelin and SHBG was observed. Our data suggest that ghrelin could be the possible link in PCOS etiology.

Key words

Women - Insulin - Obesity - Androgens - Growth hormone - Insulin-like growth factor I axis

References

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