Thyroid Hormone Pathways in Respiratory Diseases: Mechanism and Therapeutic Potential

Thyroid hormones (THs) influence a wide range of processes, from gene expression to complex signaling pathways, in almost every tissue. Over the past few years, there has been renewed interest in the TH synthesis, metabolism, secretion, and action; and the therapeutic potential of TH-related pathways and factors; as well as the mechanisms involved, including endocrine-immune/inflammatory relation. We hypothesize that TH-related factors and processes (ie, iodothyronine deiodinase, thyroid hormone transporters, etc) might influence the pathomechanism, disease course of respiratory pathology. TH-related molecules and processes may have the potential for use as indicators that may explain biological heterogeneity and/or be biomarkers of respiratory diseases. Furthermore, we postulate to explore whether the immune-inflammatory and/or other pathway components involved in lung diseases represent potential therapeutic agents. Exploration and validation of the distinctive utility of the abovementioned factors in respiratory disease should be planned and performed, paying attention to novel therapies and a panel of biomarkers, especially as the number of studies is limited and lacking, which makes it difficult to come to significant conclusions and find potential applications regarding respiratory diseases.