Serum leptin levels and GHR-d3/fl gene polymorphism in acromegalic patients with thyroid nodules.

BACKGROUND: Acromegaly is a rare and serious syndrome that is commonly associated with pituitary neoplasms. Thyroid multinodular disease is a common finding in acromegaly. Leptin is a polypeptide hormone, and studies have shown that it can increase cell proliferation and inhibit apoptosis.

OBJECTIVES: The aim of the study was to determine the relationship of serum leptin levels with certain blood parameters and determine if growth hormone receptor (GHR)-d3/fl gene polymorphism is associated with thyroid nodules in acromegalic patients.

MATERIAL AND METHODS: A total of 24 acromegalic patients with or without thyroid nodules were included in the study. Gene polymorphisms and blood parameters were examined.

RESULTS: A marked increase was observed in serum leptin concentration in acromegalic patients with thyroid nodules compared to patients without them (p < 0.05). GH levels were lower in patients without nodules than in patients with nodules (p < 0.05). Blood glucose levels were higher in patients with nodules compared to those without them (p < 0.05), and the presence of thyroid nodules was associated with decreased blood low-density lipoprotein (LDL) levels compared to patients without nodules (p < 0.05). A significant relationship was observed between growth hormone receptor (GHR)-d3/fl gene polymorphism and leptin levels in acromegalic patients with thyroid nodules (p < 0.001).

CONCLUSIONS: These data from acromegalic patients indicate that thyroid nodules are associated with increased serum leptin, GH and blood glucose levels and with decreased LDL levels. GHR-d3/fl gene polymorphism status was strongly related to higher leptin levels.