[Effect of Buyi Pishen acupuncture on inflammatory factor and cartilage matrix in adjuvant arthritis rats]

To observe the effect of Buyi Pishen acupuncture (acupuncture for invigorating spleen and kidney) on inflammatory factor and synovial cartilage matrix in adjuvant arthritis (AA) rats, and to explore the mechanism of acupuncture for rheumatoid arthritis (RA).

A total of 60 clean male Wistar rats were randomized into a normal group, a model group, a tripterygium wilfordii polyglycoside tablet (TWP) group and an acupuncture group, 15 rats in each group. Rats in the model group, the TWP group and the acupuncture group received intradermal injection of Freund's complete adjuvant (FCA) at right hind foot pad to induce the AA model. TWP suspension of 8 mg/kg was given by gavage in the TWP group. Acupuncture was applied at "Shenshu" (BL 23), "Pishu" (BL 20) and right "Housanli" (ST 36), "Sanyinjiao" (SP 6), "Yanglingquan" (GB 34) in the acupuncture group, 15 min a time, once a day. The intervention was given 15 days in both TWP group and acupuncture group. The foot-pad swelling degree before modeling, before and after intervention and the arthritis index (AI) score before and after intervention were calculated; the serum levels of interleukin (IL)-1β, IL-4, IL-10 and tumor necrosis factor-α (TNF-α) were detected by ELISA method; the ultrastructure and histomorphological changes of synovium issue were observed by transmission electron microscope and HE staining; the positive expression of matrix metalloproteinase (MMP)-3 and MMP-9 in synovium issue was detected by immunohistochemistry method.

Before intervention, foot-pad swelling degree of the model group, the TWP group and the acupuncture group was increased compared with the normal group (P<0.01). After intervention, foot-pad swelling degree and AI score were increased compared with the normal group (P<0.01), foot-pad swelling degree and AI scores in the TWP group and the acupuncture group were lower than the model group (P<0.05), and those in the acupuncture group were decreased compared with the TWP group (P<0.05). The model group exhibited unclear nuclear membrane of synovial cells, chromatin pyknosis, massive inflammatory cell infiltration and hyperplasia in synovial tissue; the TWP group and the acupuncture group exhibited clear and smooth nuclear membrane of synovial cells, inapparent chromatin pyknosis, less inflammatory cell infiltration and hyperplasia in synovial tissue, the acupuncture group exhibited less matrix destruction as well. Compared with the normal group, serum levels of IL-1β and TNF-α and positive expression of MMP-3 and MMP-9 in synovium issue were increased (P<0.01), while serum levels of IL-4 and IL-10 were decreased (P<0.01) in the model group. Compared with the model group, serum levels of IL-1β and TNF-α and positive expression of MMP-3 and MMP-9 in synovium issue were decreased (P<0.05, P<0.01), while serum levels of IL-4 and IL-10 were increased (P<0.05) in the TWP group and the acupuncture group; compared with the TWP group, serum level of TNF-α and positive expression of MMP-3 and MMP-9 in synovium issue were decreased (P<0.05), while serum levels of IL-4 and IL-10 were increased (P<0.05) in the acupuncture group.

Buyi Pishen acupuncture can effectively improve the injury of articular cartilage in AA rats, its mechanism maybe related to reducing the inflammatory reaction in synovium and inhibiting the degradation of articular cartilage matrix.