MiR-143 Inhibits Osteoclastogenesis by Targeting RANK and NF-κB and MAPK Signaling Pathways

To explore the effect of miRNA-143 on osteoclast formation and provide new ideas for the treatment of osteoporosis.

Mice macrophage lines RAW264.7 cells after transfection were divided into four groups: control group, RANKL group, RANKL combined with miR-143 mimics group and RANKL combined with miR-NC group. TARCP staining was used to observe the effect of miR-143 on osteoclast formation. The expression of RANK, TRAF6 and NFATc-1 in the upstream of RANKL pathway was detected by real-time quantitative PCR (RT qPCR) and Western blotting (WB). The binding of miR-143 to TNFRSF11A was detected by double Luciferase Reporter Analysis. The effect of miR-143 on the expression of NF-κB (p65, I-κB-α) signal pathway in osteoclasts was detected. The effects of I-BET151 on the expression of osteoclast-specific genes TRACP, MMP 9, CtsK and c-Src were detected.

The positive level of osteoclasts in RANKL group and RANKL combined with miR-NC group was significantly higher than that of RANKL combined with miR-143 mimics group and control group (P < 0.05). The expression levels of RANK, TRAF6, NFATc-1, TRACP, MMP-9, CtsK and c-Src in RANKL group and RANKL combined with miR-NC group were significantly higher than those of RANKL combined with miR-143 mimics group and control group (P < 0.05). The expression levels of I-κB-α were significantly lower than that of RANKL combined with miR-143 mimics group and control group (P<0.05).

MiR-143 can inhibit the expression of RANK, TRAF6 and downstream NFATc-1 in the RANKL pathway, thereby inhibiting the RANK/RANKL pathway. MiR-143 can inhibit the signal pathway of NF-κB (p65, I-κB-α). MiR-143 inhibits the expression of osteoclast-specific genes TRACP, MMP 9, CtsK and c-Src. That is to say, miR-143 inhibits osteoclast formation by targeting RANK, NF- κB and MAPK signaling pathways.