Work

MicroRNA-376b is involved in the pathogenesis of thyroid-associated ophthalmopathy by regulating HAS2

Year: 2023

Type: article

Abstract: Background: Accumulating data suggest that microRNAs play important roles in the pathophysiology of Graves’ disease (GD). The aim of this study was to investigate the changes in the expression of miR-376b and its downstream target, hyaluronan synthase 2 (HAS2), in patients with GD, and the molecular mechanisms involved in the pathogenesis of GD. Methods: Initial GD patients, GD patients in remission and healthy controls were recruited from Shanghai Tongji Hospital. The expression changes of miR-376b and HAS2 in peripheral blood mononuclear cells (PBMCs) were detected among three groups. 6T-CEM cells were treated with T3, hsa-miR-376b mimics or hsa-miR-376b inhibitors, respectively. Cell proliferation was detected by CCK8, and cell apoptosis was assayed by TUNEL. In addition, the gene expression was analyzed by quantitative real time polymerase chain reaction (qPCR), and the protein expression was detected by Western blotting. Results: Compared with the healthy controls, the expression of miR-376b in PBMC of initial GD patients was significantly decreased, while the expression of HAS2 was significantly increased. Compared with initial GD patients, miR-376b expression in PBMC of GD patients in remission was remarkably increased, whereas HAS2 expression was dramatically decreased. MiR-376b expression in PBMC was dramatically negatively correlated with FT3 and FT4 levels, whereas HAS2 expression showed a significant positive relationship with FT3 and FT4. Furthermore, the expression of HAS2 in PBMC showed a significant negative correlation with miR-376b. After stimulation with T3, the expression of miR-376b in 6T-CEM cells was obviously reduced compared to the controls. MiR-376b mimics significantly decreased HAS2 protein expression and the mRNA expression of ICAM1 and TNF-α in 6T-CEM cells, while miR-376b inhibitors markedly elevated HAS2 protein expression and the gene expression of ICAM1 and TNF-α. We also found that miR-376b could inhibit apoptosis of 6T-CEM cells. Conclusions: The expression of miR-376b and HAS2 in PBMCs was significantly correlated with the levels of FT3 and FT4. T3 could regulate the expression of miR-376b, while miR-376b could modulate the expression of HAS2 and inflammatory factors and inhibit cell apoptosis. We speculate that miR-376b and HAS2 may be predictors of GD pathogenesis and possible therapeutic targets of GD.

Source: Endocrine

DOI: 10.1007/s12020-023-03382-y