Liu Li, Zhou Wei, Li Ming-Yu, Zhou Lan, Zhang Liang, Wang Wen-Yi, Gong Zhi-Xian, Ai Kun
The First Affiliated Hospital/the First Clinical College of Hunan University of Chinese Medicine, Changsha 410007, China.
College of Acupuncture-moxibustion and Tuina, Hunan University of Chinese Medicine, Changsha 410208.
Zhen Ci Yan Jiu. 2022 Aug 25;47(8):696-702. doi: 10.13702/j.1000-0607.20210695.
To observe the effect of electroacupuncture (EA) of "Zusanli"(ST36) and "Guanyuan"(CV4) on the apoptosis rate of synoviocytes and protein expression of Fas, FasL and Caspase-3 in synovial tissue of adjuvant-induced arthritis (AIA) rats, so as to explore its mechanisms underlying improvement of rheumatoid arthritis （RA）.
A total of 24 rats were randomly divided into normal, model, medication and EA groups, with 6 rats in each group. The AIA model was established by injection of complete Freund's adjuvant (CFA, 0.1 mL) into the left hindlimb paw. The rats in the medication group received intraperitoneal injection of 0.35 mg/kg of methotrexate, twice a week for 4 weeks. The rats in the EA group received EA stimulation of ST36 and CV4 (20 Hz/50 Hz, 1 mA) for 20 min, 6 times a week for 4 weeks. The left hind paw volume was measured using a paw volume meter, and histopathological changes of synovial tissue were observed by light microscope after H.E. staining. The serum contents of tumor necrosis factor-α（TNF-α） and interleukin-1 （IL-1） were measured by ELISA. The apoptosis of synoviocytes was detected by terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL), and the expression of apoptosis-associated proteins Fas, FasL and Caspase-3 in synovium were detected by Western blot.
Compared with the normal group, the left hind paw volume from day 3 to 24 after administration of CFA, serum IL-1 and TNF-α contents were significantly increased (<0.01), while the expressions of Fas, FasL and Caspase-3 proteins and apoptotic rate of synoviocytes were significantly decreased in the model group (<0.01). In comparison with the model group, the paw volume from day 17 to 24 after modeling, the serum IL-1 and TNF-α contents were significantly reduced (<0.01), while the apoptotic rate of synoviocytes, expressions of Fas protein in both medication and EA groups, Caspase-3 protein in the acupuncture group and FasL protein in the medication group were increased (<0.01, <0.05). Compared with the medication group, the expression of FasL protein was decreased in EA group (<0.05). H.E. stain showed obvious hyperplasia of the synovial lining layer, and disordered arrangement of synovial cells, with edema and enlargement in some cells in the model group, which was relatively milder in both medication and EA groups.
EA of ST36 and CV4 can promote the apoptosis of synoviocytes and the expressions of Fas and FasL proteins in AIA rats, which may contribute to its role in relieving synovitis through activating Fas/FasL signaling.
观察电针“足三里”（ST36）、“关元”（CV4）对佐剂性关节炎（AIA）大鼠滑膜细胞凋亡率及滑膜组织中Fas、FasL和Caspase-3蛋白表达的影响，以探讨其改善类风湿关节炎（RA）的作用机制。
将24只大鼠随机分为正常组、模型组、药物组和电针组，每组6只。通过向左侧后肢足掌注射完全弗氏佐剂（CFA，0.1 mL）建立AIA模型。药物组大鼠腹腔注射甲氨蝶呤0.35 mg/kg，每周2次，共4周。电针组大鼠接受ST36和CV4的电针刺激（20 Hz/50 Hz，1 mA），每次20 min，每周6次，共4周。用足容积仪测量左侧后足容积，苏木精-伊红（H.E.）染色后光镜观察滑膜组织的病理变化。采用酶联免疫吸附测定（ELISA）法检测血清肿瘤坏死因子-α（TNF-α）和白细胞介素-1（IL-1）含量。采用末端脱氧核苷酸转移酶介导的缺口末端标记法（TUNEL）检测滑膜细胞凋亡情况，采用蛋白质免疫印迹法（Western blot）检测滑膜中凋亡相关蛋白Fas、FasL和Caspase-3的表达。
与正常组相比，模型组在注射CFA后第3天至第24天左侧后足容积、血清IL-1和TNF-α含量显著升高（<0.01），而Fas、FasL和Caspase-3蛋白表达及滑膜细胞凋亡率显著降低（<0.01）。与模型组相比，造模后第17天至第24天，药物组和电针组的足容积、血清IL-1和TNF-α含量显著降低（<0.01），而滑膜细胞凋亡率、药物组和电针组的Fas蛋白表达、电针组的Caspase-3蛋白表达及药物组的FasL蛋白表达均升高（<0.01，<0.05）。与药物组相比，电针组FasL蛋白表达降低（<0.05）。H.E.染色显示，模型组滑膜衬里层明显增生，滑膜细胞排列紊乱，部分细胞水肿、肿大，药物组和电针组病变相对较轻。
电针ST36和CV4可促进AIA大鼠滑膜细胞凋亡及Fas和FasL蛋白表达，可能通过激活Fas/FasL信号通路发挥缓解滑膜炎的作用。
