Anti-inflammatory effects of acupuncture in the treatment of chronic obstructive pulmonary disease

Numerous randomised controlled trials have suggested the positive effects of acupuncture on chronic obstructive pulmonary disease(COPD).However,the underlying therapeutic mechanisms of acupuncture for COPD have not been clearly summarized yet.Inflammation is central to the development of COPD.In this review,we elucidate the effects and underlying mechanisms of acupuncture from an antiinflammatory perspective based on animal studies.Cigarette smoke combined with lipopolysaccharide is often used to establish animal models of COPD.Electroacupuncture can be an effective intervention to improve inflammation in COPD,and Feishu(BL13)and Zusanli(ST36)can be used as basic acupoints in COPD animal models.Different acupuncture types can regulate different types of inflammatory cytokines;meanwhile,different acupuncture types and acupoint options have similar effects on modulating the level of inflammatory cytokines.In particular,acupuncture exerts anti-inflammatory effects by inhibiting the release of inflammatory cells,inflammasomes and inflammatory cytokines.The main underlying mechanism through which acupuncture improves inflammation in COPD is the modulation of relevant signalling pathways:nuclear factor-κB(NF-κB)(e.g.,myeloid differentiation primary response 88/NF-κB,toll-like receptor-4/NF-κB,silent information regulator transcript-1/NF-κB),mitogen-activated protein kinase signalling pathways(extracellular signal-regulated kinase 1/2,p38 and c-Jun NH2-terminal kinase),cholinergic anti-inflammatory pathway,and dopamine D2 receptor pathway.The current synthesis will be beneficial for further research on the effect of acupuncture on COPD inflammation.