[Heat-reinforcing needling inhibits oxidative stress injury via modulating the Sirt1/FoxO1 pathway in rheumatoid arthritis rats with cold syndrome].

Objectives: To observe the effects of heat-reinforcing needling on inflammation and oxidative stress in rheumatoid arthritis (RA) model rats with cold syndrome, so as to analyze the mechanism of heat-reinforcing needling in improving RA.

Methods: Male SD rats were randomly divided into blank group, model group, heat-reinforcing needling group and resveratrol group according to random number table method, with 12 rats in each group. The rat model of RA with cold syndrome was established by subcutaneous injection of bovine type II collagen and complete Freund adjuvant combined with the stimulation of cold and wet environment. After successful modeling, rats of the resveratrol group was intraperitoneally injected with resveratrol (the agonist of Sirt1, 10 mg/kg), and rats of the heat-reinforcing needling group received heat-reinforcing needling at "Zusanli"(ST36)for 30 min every day. After 14 d of continuous intervention, the synovial morphology of knee joint was observed by HE staining. The activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), contents of reactive oxygen species (ROS) and malondialdehyde (MDA) in serum were detected by WST-1 method, colorimetric method probe method, and TBA method, respectively. The mRNA and protein expression levels of silencing information regulatory factor 1 (Sirt1) and (FoxO1) in the synovial tissue of knee joint were detected by Western blot and qPCR, respectively.

Results: Compared with blank group, the fibroplasia, inflammatory cell infiltration, the relative expressions of Sirt1 mRNA and protein in synovial of knee joint, serum SOD and GSH-Px activity in model group were significantly decreased(<0.01), while the relative expressions of FoxO1 mRNA and protein, the contents of ROS and MDA were significantly increased(<0.01). After interventions, the decreased Sirt1 mRNA and protein, decreased SOD and GSH-Px activities, and the increased FoxO1 mRNA and protein, increased contents of ROS and MDA were reversed (<0.01, <0.05)in both of the heat-reinforcing needling and resveratrol groups. At the same time, the fibrous tissue proliferation and inflammatory cell infiltration around the synovial tissue of knee joint induced by RA were significantly reduced in both of the intervention groups.

Conclusions: Heat-reinforcing needling can inhibit oxidative stress injury and inflammation response in RA rats with cold syndrome, which may be related to the regulation of Sirt1/FoxO1 pathway.