Impact of thyroid function on gut microbiota in rat models

Background: Recently, the role of gut microbiota on metabolic disease is widely verified. Thyroid hormones are vital factor regarding to regulation of energy homeostasis and metabolic processes. However, the relationship between gut microbiota and thyroid function influenced on host metabolism is poorly defined. Methods: To determine whether and how gut microbiota associated with thyroid function, metagenomics analysis of bacterial population in fecal samples of rat models of hyperthyroidism (induced by levothyroxine treatment) and hypothyroidism (induced by either propylthiouracil treatment or thyroidectomy) was performed through 16S rRNA gene sequencing. Results: Our results revealed that all the thyroid dysfunction models were definitely established and gut microbiota composition varied according to the different thyroid functional status. These alterations may be used to hunt a potential mechanism(s) for regulating thyroid hormone metabolism. Besides, the abundance of S24_7, Prevotella and Prevotellaceae were evidently affected on hypothyroidism status and especially, Prevotellaceae was intensely correlated with thyroid hormone variation. Conclusion: We demonstrated that the interaction of thyroid hormones and gut microbiota did exist and it supposes that modulation of those bacteria may improve thyroid functions. Moreover, this is a new perspective study concerning relationship between thyroid dysfunction and gut microbiota using NGS (Next Generation Sequencing)-based microbial sequencing technology.