Influence of Thyroid Hormones on the Body’s Adaptive Capabilities (Review)

Thyroid hormones take an active part in the regulation of many body reactions, including adaptive responses. The purpose of this review was to analyse the role of thyroid hormones in the adaptive response of the body to stress factors. Materials and methods. The data presented in articles published in Russian and foreign scientific periodicals from 2019 to 2023 were studied. The following databases were searched: PubMed, Google Scholar, SpringerLink and eLIBRARY.RU. According to the results of this theoretical study, thyroid hormones are involved in almost all physiological processes, exerting a metabolic effect on a number of tissues and systems as well as influencing pro- and antioxidant mechanisms. In response to stress, the body consistently develops a number of adaptive reactions associated with the activity of thyroid hormones. Stressors of various nature affect the level of thyroid hormones in the body. A connection between the symptoms of thyroid dysfunction and a decrease in the body’s stress resistance has been noted, while the development of both hypo- and hyperthyroidism negatively affects the functioning of a number of organs and systems. The paper describes an interdependence between hypo-/hyperthyroidism and the body’s adaptive capabilities. The influence of thyroid hormones on the adaptive mechanisms realized at the metabolic level has been proven. There is data confirming the central role of thyroid hormones in the formation of exploratory behaviour and adaptive response. A more extensive investigation is required into the correlation between changes in the level of thyroid hormones and adaptive immune responses, as well as into the effect of thyroid hormones on the function of individual immune cells. Among the ongoing research, the article highlights studies aimed to determine patterns of changes in the level of thyroid hormones during adaptation to extreme stress, including climatic and geographical factors, as well as to find approaches to non-hormonal regulation of their concentrations in the body.