Yao Hai-Hua, Min You-Jiang, Hong Dong-Ying, Wang Li, Lu Xiu-Yun, Yang Yi-Hua
Xuhui Branch of Shanghai Sixth People's Hospital, Shanghai Eighth People's Hospital, Shanghai 200235, China.
School of Traditional Chinese Medicine, Nanchang Medical College, Nanchang 300052.
Zhen Ci Yan Jiu. 2023 Aug 25;48(8):782-90. doi: 10.13702/j.1000-0607.20220513.
To observe the effect of electroacupuncture（EA） on the expression of cytosolic phospholipase A2 （cPLA2） and apoptosis of nerve cells in rats with spinal cord injury （SCI）, so as to explore its mechanisms underlying improvement of SCI.
Seventy-two female SD rats were randomly divided into model, EA, antagonist and EA+antagonist groups, with 18 rats in each group and other 18 rats were used as the sham operation （sham） group. The SCI model was established by referring to modified Allen's method with a weight impactor. The hindlimb motor function was assessed by using Basso-Beattie-Bresnahan （BBB） score. Rats of the EA group were subjected to EA stimulation at "Dazhui"（GV14）, "Yaoyangguan"（GV3）, bilateral "Ciliao"（BL32） and "Zusanli"（ST36） for 20 min, once a day for 14 days. Rats of the antagonist group received intravenous injection followed by intraperitoneal injection of arachidonyl trifluoromethyl ketone （AACOCF3, antagonist of cPLA2）, once every other day. Rats of the EA+antagonist group received EA treatment combined with antagonist injection. After the treatment, the rats were sacrificed and the spinal cord tissue was collected for detecting the protein expression of cPLA2, p-cPLA2, Bcl-2, Bax and Caspase-3 by Western blot, and the mRNA expression of cPLA2, Bcl-2, Bax and Caspase-3 using qRT-PCR. The morphological changes of the spinal cord were detected by Nissl staining.
In comparison with the sham group, the BBB score, expression of Bcl-2 protein and mRNA were significantly down-regulated （<0.01）, whereas the expression levels of Bax, Caspase-3 and p-cPLA2 proteins and mRNAs were considerably up-regulated in the model group （<0.01）. Compared with the model group, the BBB score, expression levels of Bcl-2 protein and mRNA were significantly up-regulated （<0.01, <0.05）, while the expression levels of Bax, Caspase-3 and p-cPLA2 proteins in the EA, antagonist and EA+antagonist groups, Bax and cPLA2 mRNAs in both antagonist and EA+antagonist groups, and Caspase-3 mRNA in the EA+antagonist group were obviously down-regulated （<0.01, <0.05）. The effect of EA+antagonist was significantly superior to EA in increasing BBB score and in lowering expression of Bax and cPLA2 mRNAs （<0.01, <0.05）. Nissl staining showed reduced number of nerve cells and Nissl bodies, and striped dark blue cells in the model group, which was milder in the EA and antagonist groups, particularly in the EA+antagonist group.
EA may improve the limb motor function of SCI rats, which may be related to its functions in down-regulating the expression of p-cPLA2, Bax and Caspase-3 and up-regulating Bcl-2 to reduce the apoptosis of nerve cells in the regional spinal cord.
观察电针（EA）对脊髓损伤（SCI）大鼠胞质型磷脂酶A2（cPLA2）表达及神经细胞凋亡的影响，以探讨其改善SCI的作用机制。
将72只雌性SD大鼠随机分为模型组、电针组、拮抗剂组和电针+拮抗剂组，每组18只，另取18只大鼠作为假手术（sham）组。参照改良Allen法，用重物撞击器建立SCI模型。采用Basso-Beattie-Bresnahan（BBB）评分评估后肢运动功能。电针组大鼠于“大椎”（GV14）、“腰阳关”（GV3）、双侧“次髎”（BL32）和“足三里”（ST36）进行电针刺激20分钟，每天1次，共14天。拮抗剂组大鼠隔日静脉注射并腹腔注射花生四烯酰三氟甲基酮（AACOCF3，cPLA2拮抗剂）。电针+拮抗剂组大鼠接受电针治疗并联合注射拮抗剂。治疗后，处死大鼠，取脊髓组织，采用蛋白质印迹法检测cPLA2、p-cPLA2、Bcl-2、Bax和Caspase-3的蛋白表达，采用qRT-PCR检测cPLA2、Bcl-2、Bax和Caspase-3的mRNA表达。采用尼氏染色检测脊髓形态学变化。
与假手术组比较，模型组BBB评分、Bcl-2蛋白及mRNA表达显著下调（<0.01），而Bax、Caspase-3和p-cPLA2蛋白及mRNA表达水平显著上调（<0.01）。与模型组比较，电针组、拮抗剂组和电针+拮抗剂组的BBB评分、Bcl-2蛋白及mRNA表达水平显著上调（<0.01，<0.05），而电针组、拮抗剂组和电针+拮抗剂组的Bax、Caspase-3和p-cPLA2蛋白表达水平，拮抗剂组和电针+拮抗剂组的Bax和cPLA2 mRNA表达水平，以及电针+拮抗剂组的Caspase-3 mRNA表达水平均明显下调（<0.01，<0.05）。电针+拮抗剂组在提高BBB评分及降低Bax和cPLA2 mRNA表达方面的效果显著优于电针组（<0.01，<0.05）。尼氏染色显示，模型组神经细胞和尼氏体数量减少，出现深蓝色条纹状细胞，电针组和拮抗剂组病变较轻，电针+拮抗剂组尤为明显。
电针可改善SCI大鼠的肢体运动功能，其机制可能与下调p-cPLA2、Bax和Caspase-3的表达，上调Bcl-2以减少脊髓局部神经细胞凋亡有关。
