Effects of tyrosine on expression of thyroid cell function related gene in primary cultured rat cells

Abstract

Objective To investigate the effect of tyrosine on mRNA expression of thyroglobulin (TG),thyroid peroxidase (TPO),sodium/iodine symporter (NIS) and thyroid-stimulating hormone receptor (TSHR) in primary cultured rat thyroid cells.Methods Primary cultured rat thyroid cells were divided into three groups(cells from 5 rats in each group):control group,tyrosine group Ⅰ,and tyrosine group Ⅱ,and tyrosine of 0,5％,10％was added to the culture medium,and the cells were collected after cultured for 96 h,respectively.The mRNA levels of TG,TPO,NIS and TSHR of thyrocyte were determined by real-time quantitative PCR.Results The expression levels of TG,NIS mRNA in control group,tyrosine group Ⅰ and tyrosine group Ⅱ were 1.11 ± 0.36,2.08 ± 0.45,2.52 ± 0.65 and 1.21 ± 0.36,1.94 ± 0.57,2.10 ± 0.56,respectively.The differences were statistically significant (F =10.48,4.42,all P ＜ 0.05).The mRNA levels of TG,NIS in tyrosine group Ⅰ and tyrosine group Ⅱ were significantly higher than that of control group(all P ＜ 0.05).TPO,TSHR mRNA expression levels of control group,tyrosine group Ⅰ and tyrosine group Ⅱ were 1.02 ± 0.54,1.14 ± 0.29,1.17 ± 0.38 and 0.81 ± 0.44,0.91 ± 0.30,0.90 ± 0.19,respectively.There was no significant differences among the three groups on TPO,TSHR mRNA levels(F =0.18,0.26,all P ＞ 0.05).Conclusions Tyrosine could effect on expression of thyroid cell function related gene and increase the storage of iodine in the thyroid by stimulating the iodine pump function,which may increase iodine intake. Key words: Tyrosine; Thyroglobulin; Iodine peroxidase; Cell culture techniques