电针对KOA大鼠关节软骨及软骨下骨降解相关蛋白表达的影响*

目的：探讨电针对KOA大鼠关节软骨及软骨下骨降解相关蛋白表达的影响。方法：16只24月龄SD雄性大鼠随机分为老年组和电针组各8只，另8只6月龄SD雄性大鼠为青年组。电针组接受电针治疗（穴位：双侧“太溪”“足三里”“阳陵泉”“血海”；电针参数：疏密波，密波15Hz，疏波3Hz，电流1mA，每天1次，每次30min，每周5天，连续干预8周），其余两组不做处理。干预8周后取材，ELISA法检测血清Ⅱ型胶原C端肽（CTX-Ⅱ）含量；显微CT检测左侧胫骨软骨下骨微结构；番红-固绿染色在光镜下观察左胫骨平台软骨组织形态结构，改良Mankin’s评分评估关节软骨退变程度；RT-qPCR、Western blot检测aggrecanase-2、SIRT1 mRNA及蛋白表达水平。结果：(1)与青年组大鼠相比，老年组CTX-Ⅱ含量增高（P<0.05）；番红-固绿染色显示老年组软骨表面结构破坏严重，出现裂层，软骨与软骨下骨分界不清，形态结构异常，染色不均；改良Mankin’s评分增加（P<0.05）；骨密度、骨体积分数、骨小梁数量减少（P<0.05），骨小梁间距增大（P<0.05）...

Effects of Electroacupuncture on the Expression of Proteins Related to Degradation of Articular Cartilage and Subchondral Bone in KOA Rats

Objective: To explore the effects of electroacupuncture on the expression of proteins related to articular cartilage and subchondral bone degradation in KOA rats. Methods: Sixteen 24-month-old SD male rats were randomly divided into old age group (n=8) and electroacupuncture group (n=8), and 6-month-old SD male rats (n=8) were used as young group. The electroacupuncture group received electroacupuncture treatment, acupoints: bilateral "Taixi", "Zusanli", "Yanglingquan", "Xuehai". Electroacupuncture parameters: use dense wave, dense wave 15Hz, sparse wave 3Hz, current 1mA, once a day, 30min each time, 5 days a week, continuous intervention for 8 weeks, and the other two groups were not treated. After 8 weeks of intervention, the content of serum type Ⅱ collagen C-terminal peptide (CTX-Ⅱ) was detected by ELISA method, the subchondral bone microstructure of the left tibia was detected by micro-CT, the cartilage morphology of the left tibial plateau was observed by fuchsin-fast green staining, and the degree of articular cartilage degeneration was evaluated by modified Mankin''s score. The expression levels of aggrecanase-2, SIRT1mRNA and protein were detected by RT-qPCR and Westernblot. Results: (1)Compared with the young group of rats, the CTX-Ⅱ content in the old group increased (P＜0.05); Safranin-Fast Green staining showed that the cartilage in the old group showed serious structural damage, cracks appeared, and the cartilage and subchondral bone were not decomposed. Clear, abnormal morphological structure, uneven staining; modified Mankin''s score increased (P＜0.05); bone density, bone volume fraction, and number of trabeculae decreased (P＜0.05), and the distance between trabeculae increased (P＜0.05); the expression of aggrecanase-2 mRNA and protein increased (P＜0.05), and the expression of SIRT1 mRNA and protein decreased (P＜0.05); (2)Compared with the rats in the elderly group, the CTX-II content of the rats in the electroacupuncture group was reduced (P＜0.05); safranin-fast green staining showed that the cartilage was slightly flat, with no obvious cracks, and the staining was more uniform; Modified Mankin''s score decreased (P＜0.05); bone density increased (P＜0.05), trabecular distance decreased (P＜0.05), bone volume fraction and trabecular number tended to increase (P＞0.05), aggrecanase-2 mRNA and protein expression decreased (P＜0.05), SIRT1mRNA and protein expression increased (P＜0.05). Conclusion: Electroacupuncture can protect articular cartilage by promoting the expression of SIRT1, inhibiting the degradation of articular cartilage and improving the microstructure of subchondral bone.