Journal of Inflammation Research (Dec 2021)
The Anti-Inflammatory Actions and Mechanisms of Acupuncture from Acupoint to Target Organs via Neuro-Immune Regulation
Abstract
Ningcen Li,1,2,* Yi Guo,1,3,4,* Yinan Gong,1– 3 Yue Zhang,1,2 Wen Fan,5 Kaifang Yao,1,2 Zhihan Chen,1,2 Baomin Dou,1,2 Xiaowei Lin,1,3,4 Bo Chen,1– 3 Zelin Chen,1– 3 Zhifang Xu,1– 3 Zhongxi Lyu1– 3 1Research Center of Experimental Acupuncture Science, Tianjin University of Traditional Chinese Medicine, Tianjin City, People’s Republic of China; 2School of Acupuncture & Moxibustion and Tuina, Tianjin University of Traditional Chinese Medicine, Tianjin City, People’s Republic of China; 3National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin City, People’s Republic of China; 4School of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin City, People’s Republic of China; 5Suzuka University of Medical Science, Suzuka City, Japan*These authors contributed equally to this workCorrespondence: Zhifang Xu; Zhongxi LyuSchool of Acupuncture & Moxibustion and Tuina, Tianjin University of Traditional Chinese Medicine, No. 10 Poyang Lake Road, Tuanbo New Town, Jinghai District, Tianjin, 301617, People’s Republic of ChinaTel/Fax +86 22-5959-6290Email [email protected]; [email protected]: Inflammation plays a significant role in the occurrence and development of multiple diseases. This study comprehensively reviews and presents literature from the last five years, showing that acupuncture indeed exerts strong anti-inflammatory effects in multiple biological systems, namely, the immune, digestive, respiratory, nervous, locomotory, circulatory, endocrine, and genitourinary systems. It is well known that localized acupuncture-mediated anti-inflammatory effects involve the regulation of multiple populations and functions of immune cells, including macrophages, granulocytes, mast cells, and T cells. In acupuncture stimulation, macrophages transform from the M1 to the M2 phenotype and the negative TLR4 regulator PPARγ is activated to inhibit the intracellular TLR/MyD88 and NOD signaling pathways. The downstream IκBα/NF-κB and P38 MAPK pathways are subsequently inhibited by acupuncture, followed by suppressed production of inflammasome and proinflammatory mediators. Acupuncture also modulates the balance of helper T cell populations. Furthermore, it inhibits oxidative stress by enhancing SOD activity via the Nrf2/HO-1 pathway and eliminates the generation of oxygen free radicals, thereby preventing inflammatory cell infiltration. The anti-inflammatory effects of acupuncture on different biological systems are also specific to individual organ microenvironments. As part of its anti-inflammatory action, acupuncture deforms connective tissue and upregulates the secretion of various molecules in acupoints, further activating the NF-κB, MAPK, and ERK pathways in mast cells, fibroblasts, keratinocytes, and monocytes/macrophages. The somatic afferents present in acupuncture-activated acupoints also convey sensory signals to the spinal cord, brainstem, and hypothalamic neurons. Upon information integration in the brain, acupuncture further stimulates multiple neuro-immune pathways, including the cholinergic anti-inflammatory, vagus-adrenal medulla-dopamine, and sympathetic pathways, as well as the hypothalamus-pituitary-adrenal axis, ultimately acting immune cells via the release of crucial neurotransmitters and hormones. This review provides a scientific and reliable basis and viewpoints for the clinical application of acupuncture in various inflammatory conditions.Keywords: inflammation, acupuncture, immune, vagus, sympathetic nerve
