Serum irisin and apelin levels and markers of atherosclerosis in patients with subclinical hypothyroidism

Abstract

Objective: In this study, we aimed to evaluate serum irisin and apelin levels in patients with subclinical hypothyroidism (SCH) when they were subclinical hypothyroid and become euthyroid after levothyroxine therapy and association of these adipokines with markers of atherosclerosis such as serum homocysteine levels and carotid intima-media thickness (IMT). Subjects and methods: The study included 160 patients with newly diagnosed subclinical hypothyroidism due to Hashimoto's thyroiditis and 86 euthyroid healty subjects. Serum glucose and lipid profile, insulin, HOMA, TSH, free T3, free T4, anti-thyroperoxidase and anti-thyroglobulin antibodies, homocysteine, apelin and irisin levels were measured in all study subjects. Thyroid and carotid ultrasound examinations were performed. The subclinical hypothyroid group was reevaluated after 12-weeks of levothyroxine therapy when they became euthyroid. Results: Clinical characteristics of the patient and control group were similar. Glucose, insulin and HOMA levels, lipid parameters and free T3 were similar between the two groups.. Serum homocystein was higher and apelin was lower in patients with SCH, but irisin levels were similar between the two groups. While thyroid volume was lower, carotid IMT was significantly greater in patients with SCH (pCarotidIMT:0,01). After 12-weeks of levothyroxine therapy, all the studied parameters remained unchanged except, serum freeT4, TSH, homocystein and apelin. While homocystein decreased (p: 0,001), apelin increased significantly (p = 0,049). In multivariate analysis, low apelin levels significantly contributed to carotid IMT (p = 0,041). Conclusions: Apelin-APJ system may play a role in vascular and cardiac dysfunction in patients with SCH and treatment of this condition may improve the risk of cardiovascular disease.

Subclinical hypothyroidism contributes to poor glycemic control in patients with type 2 diabetes mellitus, and ellagic acid attenuates methimazole‐induced abnormal glucose metabolism in mice model

“…Subclinical hypothyroidism (SCH) is one of the most common endocrine disorders with a prevalence ranging from 3% to 15% in the general population and up to 20% among females with age more than 60 years or older population (Delitala et al., 2017; Yasar et al., 2019). SCH is characterized by the elevation of serum TSH levels within 10 μIU/mL, with normal serum thyroid hormones, including free thyroxine (FT4) and free tri‐iodothyronine (Surks et al., 2004).…”

Thyroid hormones modulate irisin concentrations in patients with recently onset hypothyroidism following total thyroidectomy

“…It was suggested that this might be attributed to the small number of treated patients, the short follow-up period and the variation of irisin not depending solely on TSH levels. On the other hand, two further studies described similar irisin levels in patients with subclinical hypothyroidism and in healthy control [ 7 , 11 ]. In particular, Yasar et al [ 11 ] enrolled patients with newly diagnosed subclinical hypothyroidism due to autoimmune thyroiditis (Hashimoto’s thyroiditis).…”

“…On the other hand, two further studies described similar irisin levels in patients with subclinical hypothyroidism and in healthy control [ 7 , 11 ]. In particular, Yasar et al [ 11 ] enrolled patients with newly diagnosed subclinical hypothyroidism due to autoimmune thyroiditis (Hashimoto’s thyroiditis). The authors hypothesized that thyroid tissue-derived FNDC5/irisin [ 12 ] is released in the circulation as a result of the chronic inflammation of the thyroid [ 11 ].…”

Adipocytokines and thyreopathies

“…Jednej sa nepodarilo preukázať, že by hypertyreóza alebo hypotyreóza, či už klinická alebo subklinická, akokoľvek korelovali so sérovými koncentráciami apelínu (14). Druhá zas preukázala nižšiu hladinu apelínu u hypotyreóznych pacientov oproti zdravým kontrolám (35).…”