Xing Longfei, Chen Xilin, Guo Changqing, Zhu Wenting, Hu Tingyao, Ma Weiwei, Du Mei, Xu Yue, Guo Changqing
School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, People's of Republic of China.
Department of Acupuncture and Rehabilitation, The Fifth College of Clinical Medicine, Guangzhou University of Traditional Chinese Medicine, Guangzhou, People's Republic of China.
J Pain Res. 2023 Aug 21;16:2871-2882. doi: 10.2147/JPR.S416242. eCollection 2023.
Mitochondrial dysfunction of chondrocytes has become an area of focus in Knee Osteoarthritis (KOA) in recent years. Activation of mitophagy could promote the survival of chondrocytes and alleviate cartilage degeneration. The aim of this study was to explore whether mitophagy was involved in the cartilage protection of KOA rabbits after electroacupuncture (EA) intervention.
The rabbits were divided into 3 groups, Control group, KOA group, EA group, with 6 rabbits in each group. KOA model rabbits were established by modified Videman's extended immobilization method for 6 weeks and randomly divided into KOA group and EA group. The rabbits in EA group were treated every other day for 3 weeks. The degree of cartilage degeneration was detected by Safranine O-Fast Green staining and immunofluorescence. The morphological changes of chondrocytes mitochondria were detected by transmission electron microscope. ATP concentration in cartilage was measured by ATP Assay Kit. The changes of Pink1-Parkin signal pathway were detected by immunofluorescence, Western blot, and Real-time PCR.
The morphology showed that EA could reduce the degeneration of KOA cartilage and increase the distribution of collagen II. We also found that EA could activate mitophagy in KOA rabbit chondrocytes to remove damaged mitochondria and restore mitochondrial homeostasis, which was manifested as increasing the expression of LC3 II/I, promoting the colocalization of TOM20 and LC3B, reducing the accumulation of mitochondrial markers outer mitochondrial membrane 20 (TOM20) and inner mitochondrial membrane 23 (TIM23), and increasing ATP production in chondrocytes. This regulation might be achieved by upregulating the Pink1-Parkin signal pathway.
EA may play a role in protecting KOA cartilage by activating mitophagy mediated through Pink1-Parkin pathway.
近年来，软骨细胞的线粒体功能障碍已成为膝关节骨关节炎（KOA）的一个研究热点。线粒体自噬的激活可促进软骨细胞存活并减轻软骨退变。本研究旨在探讨电针（EA）干预后线粒体自噬是否参与KOA兔的软骨保护作用。
将兔分为3组，即对照组、KOA组、EA组，每组6只。采用改良的Videman长期制动法建立KOA模型兔，持续6周，然后随机分为KOA组和EA组。EA组兔每隔一天接受治疗，共3周。采用番红O-固绿染色和免疫荧光检测软骨退变程度。通过透射电子显微镜检测软骨细胞线粒体的形态变化。使用ATP检测试剂盒测量软骨中的ATP浓度。通过免疫荧光、蛋白质免疫印迹法和实时荧光定量PCR检测Pink1-Parkin信号通路的变化。
形态学显示，EA可减轻KOA软骨退变并增加Ⅱ型胶原分布。我们还发现，EA可激活KOA兔软骨细胞中的线粒体自噬以清除受损线粒体并恢复线粒体稳态，表现为增加LC3 II/I的表达，促进TOM20与LC3B的共定位，减少线粒体标记物外膜20（TOM20）和内膜23（TIM23）的积累，并增加软骨细胞中的ATP生成。这种调节可能是通过上调Pink1-Parkin信号通路实现的。
EA可能通过激活由Pink1-Parkin途径介导的线粒体自噬对KOA软骨发挥保护作用。
