[Progress of research on mechanisms of acupuncture and moxibustion in the treatment of rheumatoid arthritis]

In the present paper, we summarize the literature about mechanisms of acupuncture and moxibustion ［including ordinary acupuncture, electroacupuncture, fire needling, warm acupuncture (acupuncture with the needle warmed by burning moxa), cheek acupuncture, wheat-sized moxibustion, suspension moxibustion, etc.］ treatments of rheumatoid arthritis (RA) both domestically and abroad in recent years. Results indicate that the role of acupuncture and moxibustion therapies in improving RA involves multi-targets and multi-levels. These targets and levels include 1) improving joint and synovial inflammatory response by regulating inflammatory cytokines, inhibiting cell adhesion factor and interferon expression, 2) directly or indirectly regulating immune cell balance, 3) regulating peripheral and central neurotransmitters (plasma CCK-8 and β-endorphin, hypothalamic prodynorphin, etc.), 4) regulating related signaling pathways (suppressing nuclear factor-kB/vascular endothelial growth factor, Janus tyrosine kinase-signal transducer and activator of transcription, transient receptor potential vanilloid and canonical Wnt/β-catenin pathways), and activating cholinergic anti-inflammatory pathway, 5) regulating histocyte energy metabolism (improving amino acid supply and reducing negative nitrogen balance to improve immune regulation function), 6) maintaining the balance of bone cells and articular cartilage (by regulating the balance between synthesis and degradation of articular cartilage matrix, and the balance of bone cells and osteoclasts), 7) up-regulating energy metabolism gene (Atp50, Atp6V1B2) expression and regulating biological rhythm gene (clock, Per2, Rev-erb) expression, 8) regulating miRNAs-mediated chondrocyte apoptosis. All these provide experimental basis for acupuncture and moxibustion treatments of RA.