<p>Brain Metabolism in Rats with Neuropathic Pain Induced by Brachial Plexus Avulsion Injury and Treated via Electroacupuncture</p>

Abstract

These authors contributed equally to this workPurpose: Brain organisation is involved in the mechanism of neuropathic pain. Acupuncture is a common clinical practise in traditional Chinese medicine for the treatment of chronic pain. This study explored electroacupuncture's effects on brain metabolism following brachial plexus avulsion injury (BPAI)-induced pain. Methods: A total of 32 female rats were randomised into a normal group, model group, sham electroacupuncture group, and electroacupuncture group. A pain model was included via right BPAI. The electroacupuncture intervention at cervical "Jiaji" points (C5-7) was performed for 11 weeks. The mechanical withdrawal threshold of the non-injured (left) forepaw was measured at the baseline and on days 3, 7, 14, 21, 28, 56, 84, and 112 subsequent to BPAI. Positron emission tomography (PET) was applied to explore metabolic changes on days 28, 84, and 112. Results: After electroacupuncture, the mechanical withdrawal threshold of the left forepaws was significantly elevated and the effect persisted until 4 weeks after the intervention ceased (p<0.05 or p<0.001). In the sensorimotor-related brain regions, standardised uptake values in the bilateral somatosensory and motor cortices were observed in the electroacupuncture group. Metabolism particularly increased in the right somatosensory cortex. Metabolism changes also occurred in the pain-related brain regions and emotion-and cognition-related brain regions. Conclusion:The present study demonstrated the beneficial effects of electroacupuncture for relieving BPAI-induced neuropathic pain in rats. Electroacupuncture intervention might inhibit maladaptive plasticity in brain areas governing multidimensional functions, especially in sensorimotor-and cognition-related cortices.

Acetylglutamine facilitates motor recovery after brachial plexus root avulsion in ratsby promoting motoneuronal survival and axonal remyelination

“…This phenomenon results in caspase-1 or caspase-4/5/11 activation to promote the secretion of proin ammatory cytokines such as interleukin-1β (IL-1β) and interleukin-18 (IL-18) leading to cell pyroptosis [27][28][29]. There is ample evidence to suggest that pyroptosis occurs extensively in diseases of the central nervous system [30,31]. Accordingly, targeting the regulation of cell pyroptosis may lead to the regulation of disease in ammation.…”

Potential mechanisms of acupuncture for neuropathic pain based on somatosensory system

“…Animal models of neuropathic pain are critical for understanding the underlying mechanism and further development of acupuncture therapy. A variety of neuropathic pain animal models which induced by central or peripheral nerve injury have been used to study the acupuncture mechanism ( Table 3 ; Zhang Y. et al, 2018 ; Li et al, 2019b ; Huo B.B. et al, 2020 ; Du et al, 2021 ; Jang et al, 2021 ; Jiang et al, 2021 ; Wei et al, 2021 ; Xu et al, 2021 ; Zou et al, 2021 ).…”

Therapeutic strategies for brachial plexus injury

“…The polyphenol curcumin may also alleviate BPA-induced pain by suppressing the levels of proinflammatory cytokines and neuropathic-associated proteins, and deactivating astrocytes [96]. Electroacupuncture and naprapathy have also been used to attenuate neuropathic pain following BPRA [45,48,95].…”