Abstract

To investigate the relationship between obestatin and TSH levels in patients who received thyroid hormone replacement and were in the euthyroid state. Included 30 patients who were followed up in the endocrinology outpatient clinic in 2020, who received L-thyroxine replacement, and 30 healthy individuals without any chronic disease who did not receive thyroid hormone replacement. Blood samples were taken from both groups for obestatin, thyroid-stimulating hormone (TSH) and free T4 hormone (fT4) levels. There is significant difference in TSH levels (p = 0.007) was found between the two groups. The obestatin levels of the L-thyroxine replacement group were lower than those of the control group (p = 0.001). No correlation was observed between the TSH and obestatin levels in the control and L-thyroxine replacement groups. In this study, obestatin levels were significantly lower in patients who received L-thyroxine replacement therapy and were in euthyroid status than those in the control group. No correlation was found between obestatin and TSH levels in the control and patient groups. As a result of this study, the thyroid gland may play a more important role in the synthesis or regulation of obestatin synthesis beyond our current knowledge.

Key words: Obestatin, hypothyroidism, obesity, thyroid gland functions