The role of miR-146b-5p in TLR4 pathway of glomerular mesangial cells with lupus nephritis.

OBJECTIVE: MicroRNAs (miRNAs) are now recognized as important regulators of gene expression. The aim of the study was to investigate the role of miR-146b-5p in the TLR4 pathway and provide the basis for the treatment of lupus nephritis.

MATERIALS AND METHODS: The glomerular mesangial cells were cultured in vitro and divided into 3 groups: control group, a group of miR-146b-5p mimic added, and a group of miR-146b-5p inhibitor added. The levels of IL-6 and IL-8 in the cell culture supernatant of the three groups were detected by ELISA. The cell proliferation was detected by MTT. The expressions of MiR-146b-5p and TLR4 pathway-associated factor TRAF6 were detected by RT- PCR. The expression of TRAF6 and IRAK1 protein was detected by Western blot.

RESULTS: The overexpression of miR-146b-5p could reduce the level of IL6 and IL8 in cell culture and inhibit glomerular mesangial cell proliferation in some degree. Also, the overexpression of miR-146b-5p could inhibit the expressions of TLR4 pathway-associated factor TRAF6 and IRAK1mRNA, and the expressions of TRAF6 and IRAK1 protein.

CONCLUSIONS: MiR-146b-5p attenuated the inflammatory response of glomerular mesangial cells by inhibiting the expressions levels of TRAF6 and IRAK1 in lupus nephritis.