Nature breakthrough!

Responsible Editor | One of the core mechanisms of acupuncture and moxibustion in the treatment of diseases is to remotely regulate body functions by stimulating specific parts of the body (acupoints), and the meridian is considered to be an important transmission carrier to achieve this remote effect
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Although modern anatomical research has not yet clarified the existence of the specific structural basis of the meridian, it has revealed that the long-range effect of acupuncture stimulation can be realized through the somatosensory nerve-autonomic nerve reflex
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This reflex first activates the peripheral sensory nerve fibers located in the dorsal root ganglion (DRG) or trigeminal ganglion, and then transmits sensory information to the spinal cord and brain, thereby activating the peripheral autonomic nerves, and finally realizing the regulation of various functions
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Since the 1970s, it has been discovered that such reflexes have somatic area specificity
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In 2020, the Harvard Medical School Professor Ma Qiufu’s team published in Neuron’s research results, revealing that low-intensity acupuncture to stimulate acupoints on the hind limbs of mice (such as Zusanli ST36) can activate the vagus nerve-adrenal anti-inflammatory pathway, while acupuncture stimulates acupuncture points on the abdomen (such as ST36).
Tianshu ST25) cannot induce this anti-inflammatory pathway (see BioArt report for details: Neuron | Ma Qiufu team reported that acupuncture activates different autonomic nerve pathways to regulate systemic inflammation)
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The neuroanatomical basis behind this body region specificity (or the relative specificity of acupuncture points) is still unclear
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On October 13, 2021, Professor Ma Qiufu’s team and Professor Wang Yanqing of Fudan University and Professor Jing Xianghong from the Institute of Acupuncture and Moxibustion of China Academy of Chinese Medical Sciences (first authors are Dr.
Liu Shenbin and Dr.
Wang Zhifu) published an article in Nature on A neuroanatomical basis for electroacupuncture to drive the vagal-adrenal axis, achieving a historic breakthrough in acupuncture research, revealing a type of PROKR2-Cre labeled DRG sensory neurons, which is essential for low-intensity acupuncture to activate the vagal-adrenal anti-inflammatory pathway
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It is particularly noteworthy that according to the physical distribution characteristics of such nerves, the anti-inflammatory effects of low-intensity electroacupuncture at different locations can be predicted, which provides a modern neuroanatomical basis for the relatively specific existence of acupoints
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First, the myelinated neurons labeled with PROKR2-Cre are mainly enriched and expressed in the DRG innervating the limb segments, and such neurons specifically innervate the deep fascia tissues of the limbs (such as periosteum, joint ligaments and myofascial membranes).
Etc.
) without dominating the epidermal tissue of the skin and the main fascial tissue of the abdomen (such as the peritoneum)
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Secondly, in order to study the role of PROKR2-Cre-labeled neurons in acupuncture-induced vagus nerve-adrenal gland anti-inflammatory pathway, the research team used cross-inheritance and other methods to specifically knock out such DRG sensory neurons
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After knocking out such neurons, low-intensity acupuncture to stimulate the hindlimb acupoint ST36 could not activate the vagus nerve-adrenal pathway, nor could it inhibit the inflammatory storm induced by LPS (bacterial lipopolysaccharide); but knocking out such neurons did not affect the high Intensively stimulate the anti-inflammatory pathways of sympathetic nerves induced by acupoint ST36 in the hind limbs and acupoint ST25 in the abdomen
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The research team further used the method of cross-inheritance to specifically induce the expression of the photosensitive protein CatCh in PROKR2-Cre-labeled neurons, and used 473nm blue light to specifically activate such sensory nerve fibers innervating the acupoint ST36 of the hind limbs
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Studies have found that activating such nerve fibers can significantly induce the discharge of the efferent vagus nerve, and can induce the adrenal gland to release catecholamine neurotransmitters in a vagus-dependent manner, inhibit the release of pro-inflammatory cytokines induced by LPS, and significantly improve animal survival Rate
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The results of this part of the study almost simulate the anti-inflammatory effect of low-intensity electric acupuncture stimulation of ST36 on the hind limbs
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Finally, the researchers accurately verified the structural basis of the anti-inflammatory effect induced by low-intensity electroacupuncture stimulation based on the tissue innervation pattern of sensory nerve fibers labeled with PROKR2-Cre
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In contrast to the dense projections in the fascia tissue near the tibia of the lower limbs, the muscle tissues of the back of the lower limbs, including the calf gastrocnemius muscle and the semitendinosus muscle of the thigh, are less innervated by PROKR2-Cre sensory nerve fibers
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Low-intensity acupuncture stimulation of these sites failed to significantly inhibit the inflammatory response induced by LPS
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Amazingly, the gastrocnemius and semitendinosus muscles, where PROKR2-Cre nerve fibers rarely project, happen to be rarely distributed in traditional acupuncture points
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Further research found that the sensory neurons labeled with PROKR2-Cre are also densely innervated to the deep fascia tissues of the forelimbs (such as the periosteum of the radius).
The deep branch of the nerve was stimulated with bilateral low-intensity, and it was found that acupuncture stimulation of this acupoint can also significantly inhibit the LPS-induced inflammatory response through such neuron and vagus nerve-dependent methods
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The above studies have shown that for acupuncture stimulation to induce the vagus nerve-adrenal gland anti-inflammatory pathway, there are body site selectivity (such as effective ST36, LI10 and ineffective ST25 acupoints) and acupoint specificity (such as ST36 and ineffective hindlimb muscles in the traditional Non-acupoints)
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The relative specificity of this acupuncture point is related to the site-specific distribution of PROKR2 nerve fibers
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In addition, acupuncture intensity, depth, and test result indicators are all important factors that affect the specificity of acupuncture points
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These findings enrich the modern scientific connotations of acupuncture and other body surface stimulation therapies, and provide important scientific basis for clinical optimization of acupuncture stimulation parameters, inducing different autonomic reflexes, and treating specific diseases (such as inflammatory storms, etc.
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It is reported that the research was supported by Professor Wang Yanqing of Fudan University, Researcher Jing Xianghong from the Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Associate Professor Wang Zhifu, Fujian University of Traditional Chinese Medicine, Dr.
Su Yangshuai from the Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, and Yang Wei and Qi Lu , Fu Mingzhou participated in the work of this research
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Original link: https://doi.
org/10.
1038/s41586-021-04001-4 Plate maker: Notes for reprinting on the 11th [Non-original article] The copyright of this article belongs to the author of the article.
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