Microbiome and thyroid diseases: future precision studies of the gut-thyroid axis to facilitate the adjuvant treatment

Arman Karimi Behnagh Karimi Behnagh; Mahsa  Bourbour; Sakineh Moghaddam Shiri; Omolbanin  Asadi; Maryam  Honardoost

doi:10.18502/ijm.v18i2.21297

Arman Karimi Behnagh Karimi Behnagh Breast Cancer Research Center, Iran University of Medical Sciences, Tehran, Iran
Mahsa Bourbour Breast Cancer Research Center, Iran University of Medical Sciences, Tehran, Iran
Sakineh Moghaddam Shiri Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences, Tehran, Iran
Omolbanin Asadi Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences, Tehran, Iran
Maryam Honardoost Breast Cancer Research Center, Iran University of Medical Sciences, Tehran, Iran

DOI: https://doi.org/10.18502/ijm.v18i2.21297

Keywords: Thyroid function; Thyroid disease; Microbiome; Dysbiosis

Abstract

Background and Objectives: The gut microbiome is a key determinant of overall health, impacting numerous bodily func- tions, such as those of the endocrine glands. The effect of the microbiota on thyroid function has become a matter of interest, more so since the revelation of the possible link between intestinal disease and autoimmune thyroid disorders (AITDs). This review aims to provide an in-depth insight into the possible link between gut microbiota and thyroid diseases and metabolism of thyroid hormones.

Materials and Methods: A set of online sources including, PubMed, Scopus, Google Scholar and CENTRAL were compre- hensively searched to find the studies relevant to the topic of the review. Only reports in English were included in this review. Results: It has been proposed that damage to the intestinal barrier is a key element in the passage of antigens from the lumen into the bloodstream and their subsequent contact with the immune system. In addition to AITDs, dysbiosis has been shown to be linked with thyroid cancers, in which higher counts of certain bacteria associated with inflammation and carcinogenesis have been identified.

Conclusion: The majority of the available literature is focused on the differences in the microbial strain composition in in- dividuals with thyroid disorders compared to that of healthy controls. Nonetheless, the current body of evidence has implied on possible role gut microbiome in the development of thyroid diseases.