| Objective To investigate the effect of miR-22-3p on osteoclast activity in osteoporosis (OP) mice based on the ROS/TXNIP/NLRP3 pathway. Methods Female mice were used to construct the OP model by bilateral ovariectomy. Mice were randomly assigned into OP group, agomir-NC group, miR-22-3p agomir group, miR-22-3p agomir+pc-NC group, and miR-22-3p agomir+pc-TXNIP group, with 12 mice in each group. The other 12 mice were included as the sham surgery (Sham) group. ELISA was applied to detect serum bone metabolism indicators CTX-I, TPACP5b, PINP, OC, and inflammatory factors IL-1β and IL-18. Micro-CT was applied to detect microstructure changes in mouse femoral trabeculae (BMD, BV/TV, Tb.N, Tb.Th). HE staining was applied to observe morphological changes in bone tissue. TRAP staining was applied to analyze the number of osteoclasts per square millimeter of the bone tissue (N.Oc/T.A). Dihydroethidium (DHE) staining was applied to detect ROS level in the bone tissue. qRT-PCR was applied to detect the mRNA expressions of miR-22-3p, TXNIP, and NLRP3 in the bone tissue. Western blotting was applied to detect the expressions of TXNIP and NLRP3 proteins in the bone tissue. Results Compared to those in the Sham group, the levels of serum CTX-I, TPACP5b, IL-1β, IL-18, the levels of N.Oc/T.A and ROS in the femurs, and mRNA and protein expressions of TXNIP and NLRP3 in OP group increased, the levels of serum PINP, OC and the levels of BMD, BV/TV, Tb.N. Tb.Th and miR-22-3p in the femurs decreased (P<0.05). Compared to those in the OP group and agomir-NC group, the levels of serum CTX-I, TPACP5b, IL-1β, and IL-18, the levels of N.Oc/T.A and ROS in the femurs, and mRNA and protein expressions of TXNIP and NLRP3 in miR-22-3p agomir group decreased, and the levels of serum PINP and OC and the levels of BMD, BV/TV, Tb.N. Tb.Th, and miR-22-3p in the femurs increased (P<0.05). Overexpression of TXNIP greatly eliminated the improvement effect of miR-22-3p mimics on the bone metabolism imbalance in OP mice. MiR-22-3p had a targeted relationship with TXNIP. Conclusion Overexpression of miR-22-3p may relieve the bone metabolism imbalance and microstructure changes in OP mice by inhibiting the ROS/TXNIP/NLRP3 signaling pathway and by suppressing osteoclast activity. |