Expression,distribution,and activity of TSHR in human microglia

CHEN Xuelan; FU Shien; KUANG Yaqi; ZHU Yingli; HUANG Zhenxing; YANG Haiyan; LUO Zuojie

doi:10.3969/j.issn.1002-266X.2024.14.005

Abstract：Objective To investigate the expression,distribution,and activity of thyroid-stimulating hormone receptor(TSHR)in human microglia(HMC3).Methods In this study,we used human microglial cells(HMC3)as the experimental group and human thyroid cells and hepatocytes as the controls.Reverse transcription polymerase chain reaction was used to detect the expression of TSHR mRNA to identify the transcript of TSHR mRNA.Western blotting and immunofluorescence staining analysis was used to detect TSHR protein level and the distribution in HMC3 cells.HMC3 cells were divided into the 0,20,50,100,200 ng/mL thyroid-stimulating hormone receptor-stimulat-ing antibody(TSAb)groups and negative control group.Each group was preincubated with 100 μmol/L phosphodies-terase inhibitor(IBMX)for 60 minutes.The corresponding concentrations of TSAb were added to cells of the TSAb groups and then they were incubated for 24 h.We measured cyclic adenosine monophosphate(cAMP)levels by immu-noassay kits to verify the functional activity of TSHR in HMC3 cells.Results TSHR mRNA was detected in HMC3 cells with the same sequence as mRNAs derived from human thyroid cells and hepatocytes.TSHR protein was ex-pressed in the cell membrane of HMC3 cells.Compared with the 0 ng/mL TSAb group,there was no significant statis-tical difference in cAMP levels in the 20 ng/mL TSAb group.However,cAMP levels increased in the 50,100,and 200 ng/mL TSAb groups,and the high-concentration group had higher cAMP levels than the low-concentration group(P<0.05 or P<0.01).Conclusion TSHR is expressed in the cell membrane of human microglia and has a signal-ing function.