黄芪对大鼠胫前肌失神经肌萎缩的防治研究

Study on preventive and therapeutic effects of Astragali Radix on denervated tibial muscle atrophy in rats

目的:研究黄芪对大鼠胫前肌失神经肌萎缩的影响,并探讨其机制。方法:建立大鼠腓总神经夹伤模型,将造模后的60只SPF级SD大鼠随机分为6组:黄芪高、中、低剂量组、弥可保组、模型组、假手术组。术后每日灌胃给药。术后18 d,病理切片染色,形态学分析,计算胫前肌湿重比与横截面积,并用实时荧光定量PCR检测Angptl4与PI3K基因的差异表达。结果:①湿重比:与模型组相比,黄芪高、中剂量组明显增高(P<0.05或P<0.01);②横截面积:假手术组较大,形态规则;模型组明显减小,结构紊乱,结缔组织明显增生;黄芪各组与弥可保组横截面积较小,形态较规则,结缔组织增生不明显。与模型组相比,黄芪各组明显增加(P<0.01);③运动终板:假手术组为棕黑色,形状为椭圆形或圆形,着色均匀,黄芪高剂量组与弥可保组边缘较粗糙;黄芪中、低剂量组与模型组数量逐渐减少,形态不规则,边缘不光滑;着色也逐渐变浅;④Angptl4与PI3K mRNA:与模型组相比,黄芪高剂量组明显升高(P<0.05)。结论:黄芪对失神经肌萎缩具有明显的防治作用,它可能通过增加Angptl4,PI3K基因表达从而延缓肌萎缩的发生。

Objective： To study the effect of Astragali Radix on the denervated tibial muscle atrophy in rats, and discuss its mechanism. Method： Totally 60 SPF-grade Sprague-Dawley rats were selected in the common peroneal nerve crush model, and then randomly divided into 6 groups： Astragali Radix high-dose, medium-dose, low-dose groups, the Mecobalamin group, the model group, and the sham operation group. They were administered with drugs after the operation. At 18 d, the pathological section staining and morphological analysis were performed. The wet-weight ratio and section area of tibial muscles were also measured. The real-time fluorescence quantification was adopted to detect the differential expression between Angptl4 and PI3K genes. Result： ①Wet-weight ratio： The wet-weight ratio in Astragali Radix high-dose, medium-dose groups was much higher than that in the model group （P〈0.05 or P〈0.01）. ②Section area： The sham operation group was higher, with regular morphology; Whereas the model group showed significant decrease, with chaotic structure and obvious connective tissue proliferation; Astragali Radix groups and the mecobalamin group showed relatively small section areas, with chaotic structure and unobvious connective tissue proliferation. Compared with the model group, Astragali Radix groups showed significant increase （P〈0.01）. ③Motor end plate： The sham operation group was in uniform brownish black color and oval or round shape; Astragali Radix medium-dose and high-dose group and the mecobalamin group showed rough line edges; Astragali Radix medium-dose and low-dose groups and the model group showed decline in the number, with irregular morphology, rough line edges and a light color. ④Angptl4 and PI3K： Compared with the model group, the Astragali Radix high-dose group showed significant increase （P〈0.05）. Conclusion： Astragali Radix has a significant effect in preventing and treating denervated tibial muscle atrophy. It may delay the muscle atrophy by increasing Angptl4 and PI3K gene expressions.