Serum active ghrelin levels in hypothyroidism

Serum Active Ghrelin Levels in Hypothyroidism OBJECTIVE: Ghrelin is a 28 aminoacid peptide predominantly produced by the stomach oxyntic-XA like cells. Ghrelin has been discovered as a natural ligand of the growth hormone receptor but has effects on energy metabolism, food intake, gastric acidity and motility also on pancreas function. Alterations in thyroid function are associated with a large variety of symptoms, including changes in body weight and food intake. Unexpectively, ghrelin levels in hyperthyroidism is found to be decreased. In the case of hypotyhroidism controversial results have been reported. The aim of this study is to eveluate ghrelin levels in hypothyroidism. DESIGN: 30 hypothyroid patients were evaluated with 23 age, sex, body mass index matched controls. Fasting plasma TSH, fT4, fT3, anti-thyroglobulin, anti-thyroidperoxidase, total-LDL-HDL cholesterol, triglyseride, c-reactive protein, gastrin, insulin, glucose and ghrelin levels were studied. Ghrelin was eveluated with Linco active ELISA KIT. Aprotinin SIGMA was added to samples. Samples were centrifugated at +4 0 C 1500g for15 minutes. They were kept - 400C till the time for eveluation. RESULTS: Ghrelin levels vere significantly elevated according to the control group. After euthyroidism was maintained ghrelin levels were similar with the controls. Ghrelin correlated negatively with fT3 and fT4 and positively with HDL levels. CONCLUSION: Ghrelin could be the reason for weight gain and increased adiposity in hypothyroidism. Whether circulating ghrelin plays an important role in feeding behaviour and energy homeostasis is not still known. However, our results indicate that active ghrelin may have some critical actions in hypothyroidism induced weight gain. Further studies are needed to clarify the exact mechanism.