Zhang Yidan, Lin Caihong, Yang Qingqing, Wang Yuanzeng, Zhao Wen, Li Lei, Ren Xiuhua, Zhao Jianyuan, Zang Weidong, Cao Jing
Department of Human Anatomy, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan, China; Neuroscience Research Institute, Zhengzhou University Academy of Medical Sciences, Zhengzhou, Henan, China.
Department of Human Anatomy, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan, China.
Neuromodulation. 2023 Apr;26(3):563-576. doi: 10.1016/j.neurom.2022.07.009. Epub 2022 Aug 25.
Electroacupuncture (EA) is a traditional Chinese therapeutic technique that has a beneficial effect on neuropathic pain; however, the specific mechanism remains unclear. In this study, we investigated whether EA inhibits spinal Ca/calmodulin-dependent protein kinase II (CaMKIIα) phosphorylation through Sirtuin 3 (SIRT3) protein, thus relieving neuropathic pain.
We used wild-type and SIRT3 knockout (SIRT3) mice and used chronic constriction injury (CCI) as a pain model. We performed Western blotting, immunostaining, von Frey, and Hargreaves tests to gather biochemical and behavioral data. Downregulation and overexpression and spinal SIRT3 protein were achieved by intraspinal injection of SIRT3 small interfering RNA and intraspinal injection of lentivirus-SIRT3. To test the hypothesis that CaMKIIα signaling was involved in the analgesic effects of EA, we expressed CaMKIIα-specific designer receptors exclusively activated by designer drugs (DREADDs) in the spinal dorsal horn (SDH) of mice.
These results showed that the mechanical and thermal hyperalgesia induced by CCI was related to the decreased spinal SIRT3 expression in the SDH of mice. A significant reduction of mechanical and thermal thresholds was found in the SIRT3 mice. SIRT3 overexpression or EA treatment alleviated CCI-induced neuropathic pain and prevented the spinal CaMKIIα phosphorylation. Most importantly, EA increased the expression of spinal SIRT3 protein in the SDH. Downregulation of spinal SIRT3 or CaMKIIα Gq-DREADD activation inhibited the regulatory effect of EA on neuropathic pain.
Our results showed that CaMKIIα phosphorylation was inhibited by spinal SIRT3 in neuropathic pain and that EA attenuated CCI-induced neuropathic pain mainly by upregulating spinal SIRT3 expression in the SDH of mice.
电针是一种中医疗法，对神经性疼痛具有有益作用；然而，其具体机制仍不清楚。在本研究中，我们探究电针是否通过沉默调节蛋白3（SIRT3）蛋白抑制脊髓钙/钙调蛋白依赖性蛋白激酶II（CaMKIIα）磷酸化，从而缓解神经性疼痛。
我们使用野生型和SIRT3基因敲除（SIRT3 -/-）小鼠，并采用慢性缩窄损伤（CCI）作为疼痛模型。我们进行了蛋白质免疫印迹、免疫染色、von Frey和热辐射测试，以收集生化和行为学数据。通过脊髓内注射SIRT3小干扰RNA以及脊髓内注射慢病毒 - SIRT3来下调和上调脊髓SIRT3蛋白。为了验证CaMKIIα信号通路参与电针镇痛作用的假说，我们在小鼠脊髓背角（SDH）中表达了仅由设计药物（DREADDs）激活的CaMKIIα特异性设计受体。
这些结果表明，CCI诱导的机械性和热痛觉过敏与小鼠SDH中脊髓SIRT3表达降低有关。在SIRT3 -/-小鼠中发现机械和热阈值显著降低。SIRT3过表达或电针治疗可减轻CCI诱导的神经性疼痛，并防止脊髓CaMKIIα磷酸化。最重要的是，电针增加了SDH中脊髓SIRT3蛋白的表达。脊髓SIRT3下调或CaMKIIα Gq - DREADD激活抑制了电针对神经性疼痛的调节作用。
我们的结果表明，在神经性疼痛中脊髓SIRT3抑制CaMKIIα磷酸化，并且电针主要通过上调小鼠SDH中脊髓SIRT3表达来减轻CCI诱导的神经性疼痛。
