Source: Oncogene  |  Posted 9 years ago

Ghrelin levels fall in women with polycystic ovaries syndrome and correlate strongly with insulin resistance.

This suggests that ghrelin, a recently discovered growth hormone secretagogue, could be linked to insulin resistance in women with polycystic ovaries syndrome, say researchers in Hannover, Germany. But, whether the low ghrelin is a cause of insulin resistance or its consequence needs further study, the researchers say.

They noted that polycystic ovaries syndrome is associated with adiposity and metabolic changes which predispose women to insulin resistance and diabetes.

Because ghrelin is closely involved in the control of appetite and weight regulation, the researchers studied its level in 26 otherwise healthy women with polycystic ovaries syndrome. These volunteers were compared with 61 healthy female controls and five gastrectomised women.

Insulin sensitivity was measured in all patients by homeostasis model assessment (HOMA) and continuous infusion of glucose with model assessment (CIGMA) in all patients.

The women with polycystic ovaries syndrome had significantly lower serum ghrelin levels than healthy controls, whether lean or obese.

Those with polycystic ovaries syndrome who were insulin sensitive had ghrelin concentrations which compared well with the healthy controls. By contrast, in women who were insulin-resistant, ghrelin levels were significantly lower and indistinguishable from the levels in the gastrectomised women.

Ghrelin closely correlated to insulin sensitivity. When 10 insulin-resistant women with polycystic ovaries syndrome were given metformin, circulating fasting ghrelin concentrations increased significantly.

Ghrelin levels did not correlate with any of the parameters of hyperandrogenaemia or with LH/FSH ratio, body mass index or fasting insulin and glucose concentrations.