Autoimmune thyroid disease(AITD)is a disease in clinical work,which is developed by the combined action of immune dysfunction and environmental abnormalities and other factors based on the genet-ic factor.In recent years,with the continual improvement of living level,people are more concerned about their health,the detection rate of AITD has increased.Studies find that the occurrence of AITD is closely related to the abnormal immunity mediated by T lymphocytes.As an organ-specific disease,AITD mainly includes Graves'disease(GD)and Hashimoto thyroiditis(HT).Selenium is an essential trace element in human body.In recent years,it has been found that the selenium preparations are involved in immune regulation,and have the functions for maintaining immune homeostasis,improving chronic inflammation and alleviating im-mune disorders of thyroid tissue.This paper reviews the research progress on the effects of selenium on AI-TD,aiming to provide the new ideas for the prevention and treatment of AITD.

Objective To investigate the effect of subclinical hypothyroidism during pregnancy on hippocampus insulin-like growth factor Ⅰ (IGF-Ⅰ) signaling pathway in rat offspring.Methods A total of 60 female Wistar rats were evenly divided into control(CON),subclinical hypothyroidism(SCH),and clinical hypothyroidism (CH) groups.The hippocampus of progenies were collected on the postnatal day 3,postnatal day 7 to measure protein kinase B (Akt) and phosphorylated-Akt (p-Akt) by Western blot,IGF-Ⅰ and insulin-like growth factor Ⅰ receptor (IGF-Ⅰ R) by Elisa.Morris water maze and field excitatory postsynaptic potential long-term potentiation were measured at the postnatal 40 day.Results Western blot and Elisa revealed that levels of IGF-Ⅰ,IGF-Ⅰ R,and p-Akt of pups from SCH group were lower than that of CON group and were higher than CH group on day 3 (P ＜ 0.05).On day 7,the levels of IGF-Ⅰ,IGF Ⅰ R,and p-Akt of pups from SCH group were lower than CON group (P＜ 0.05),but no difference was observed in p-Akt and IGF-Ⅰ R level between SCH group and CH group (P ＞ 0.05).Latencies of all groups had shortened in Morris water maze test with increasing of training trials.The slope of field excitatory postsynaptic potenial was increased in all groups after Theta burst stimulation.The amplification percentage of slope of field excitatory postsynaptic potenial in SCH group's was lower than control group's but was higher than CH group's(all P values＜0.05).Conclusions Maternal subclinical hypothyroidism impairs long-term potentiation induction in hippocampus of rat might be associated with the levels of IGF-Ⅰ,IGF-Ⅰ R,and p-Akt.