Combined Treatment with Myo-Inositol and Selenium Ensures Euthyroidism in Subclinical Hypothyroidism Patients with Autoimmune Thyroiditis
Background. Hashimoto's thyroiditis (HT), also known as chronic lymphocytic thyroiditis or chronic autoimmune thyroiditis, is the most common form of thyroiditis affecting more than 10% of females and 2% of males. The present study aims to evaluate the beneficial effect of a combined treatment, Myo-Inositol plus selenomethionine, on subclinical hypothyroidism. Methods. The study was designed as a double-blind randomized controlled trial. Eligible patients were women diagnosed with subclinical hypothyroidism having Tg antibodies (TgAb) titer higher than 350 IU/mL. Outcome measures were Thyroid Stimulating Hormone (TSH) levels, thyroid peroxidase antibodies (TPOAb) and TgAb titer, selenium, and Myo-Inositol plasma concentration. Results. In the present paper, we demonstrated that the beneficial effects obtained by selenomethionine treatment on patients affected by subclinical hypothyroidism, likely due to the presence of autoantibody (TPOAb and TgAb), are further improved by cotreatment with Myo-Inositol. Conclusions. Indeed, due to its action as TSH second messenger, Myo-Inositol treatment reduces TSH levels closer to physiological concentrations.[..]
The present study was performed as a prospective randomized double-blinded, controlled study in women ( ; mean age 38 years) with autoimmune thyroiditis and TPOAb; inclusion criteria were TgAb and /or TPOAb above 350 IU/mL, TSH levels between 4,01 mIU/L and 9,99 mIU/L, and a normal free-thyroxine level (0.6–1.8 ng/dL) as well as typical hypoechogenicity of the thyroid in high-resolution sonography. The primary endpoint of the study was restoration of TSH levels (lower than 4 mIU/L). Secondary end points were decreased in serum TPOAb and TgAb concentrations, free thyroid hormone levels and improvement of the thyroid and quality of life estimation. All patients enrolled signed an informed consent. Patients were randomized into 2 groups according to their initial TPOAb concentrations. group A consisted of 24 patients who received orally 83 g selenomethionine/day, in a soft gel capsule; group B consisted of 24 patients who received a combined treatment plus Myo-Inositol 600 mg also in a 83 g selenomethionine, soft gel capsule, orally, for 6 months. The patients were asked to take the medication with water about 2 h before or after a meal. They were not given further treatment, such as over-the-counter vitamins or trace elements. All patients were otherwise healthy. No patients were substituted with L-T4. TPOAb, TgAb, TSH, and free thyroid hormones were determined by commercial assays. The echogenicity of the thyroid was monitored with high-resolution ultrasound.[..]
Autoantibody titer, TPOAb and TgAb, significantly decreased in both groups. In particular, TPOAb concentration decreased significantly in the group A by 42% (905.6 ± 401.6 versus 522.6 ± 236.8 mIU/mL, ) and TgAb decreased by 38% (1080.8 ± 485.1 versus 670.1 ± 300.8 mIU/mL, ). In group B, TPOAb decreased by 44% (913.9 ± 543.9 versus 516.1 ± 315.4 mIU/mL, ) and TgAb decreased by 48% (1019 ± 374.2 versus 533.9 ± 258.4 mIU/mL, ).
Eleven patients in the combined treated group showed a reduction of the TgAb below the threshold identified as inclusion criterion, compared to three patients in group A. Ultrasound of the thyroid showed normalized echogenicity in these patients.[..]
The beneficial effect obtained by Myo-Inositol is easily explained by its biological role in signaling TSH hormone; indeed, inositol regulate H2O2-mediated iodination [4] and it has been shown that hypothyroidism can be caused by an impairment of the inositol-depended TSH signaling branch (TSH resistance) [5]; therefore, by increasing the amount of the second messenger, we can increase the TSH sensitivity.