In a study of women with Hashimoto's thyroiditis who still have normal thyroid hormone levels, researchers found that blood levels of the peptide kisspeptin (and also the hormone galanin) were higher than in healthy women. This suggests these molecules might be linked to the early stages of thyroid auto‑immunity, but the study didn’t test any treatments or give dosing advice.

The hallmarks of Hashimoto's thyroiditis (HT) include the destruction of thyroid cells by leading to insulin resistance (IR), hypothyroidism, and metabolic abnormalities. Kisspeptin, spexin, and galanin control appetite and body weight (BW) to regulate metabolisms. Here, we sought to determine if galanin, kisspeptin, and spexin are linked to the pathophysiology of HT in euthyroid female individuals. Forty-five women with HT and 45 healthy control women of the same age participated in the current study. The enzyme-linked immunosorbent assay (ELISA) method was used to measure the serum levels of galanin, spexin, and kisspeptin. In comparison to the controls, HT patients had significantly higher levels of kisspeptin (<i>p</i>&#x2009;&lt;&#x2009;0.01), galanin (<i>p</i>&#x2009;&lt;&#x2009;0.01), anti-thyroid peroxidase (anti-TPO) (<i>p</i>&#x2009;&lt;&#x2009;0.001), anti-thyroglobulin (anti-Tg) (<i>p</i>&#x2009;&lt;&#x2009;0.001), and body mass index (BMI) (<i>p</i>&#x2009;&lt;&#x2009;0.05). The two groups were comparable in terms of spexin, free triiodothyronine-3 (fT3), fT4, thyroid-stimulating hormone (TSH) levels, and homeostatic model assessment for insulin resistance (HOMA-IR). Galanin and kisspeptin were seen to have a positive correlation (<i>p</i>&#x2009;&lt;&#x2009;0.01; <i>r</i>&#x2009;=&#x2009;0.786). Euthyroid women with HT were found to have higher levels of kisspeptin and galanin. These results imply that kisspeptin and galanin may be linked to the pathogenesis of hypothyroidism, and as a result, we believe that these markers may be beneficial in the early detection and treatment of HT patients.