补阳还五汤通过BDNF/TrkB介导PI3K/Akt信号通路抗脊髓神经元凋亡的机制研究

Study on mechanism of Buyang Huanwu Decoction against spinal cord neuronal apoptosis through BDNF/TrkB-mediated PI3K/Akt signaling pathway

目的探讨补阳还五汤通过BDNF/TrkB介导PI3K/Akt信号通路抗脊髓神经元凋亡的机制。方法将48只SD大鼠分为标准模型组、补阳还五汤组、抑制剂组、假手术组四组,每组各12只。采用标准方法损伤大鼠脊髓,分别连续治疗7 d。改良神经功能评分(mNSS)评价大鼠经7 d治疗后神经功能,进行组织切片,用尼氏染色(NS)法、免疫组织化学法(Immunohistochemistry)和蛋白质印记(WB)法分别检测各组脊髓神经元细胞形态及BDNF、TrkB、PI3K/Akt的表达情况。结果给药治疗后对各组大鼠第1、3、7天mNSS评分,补阳还五汤组、抑制剂组分别与标准模型组相比,得分均有明显降低(P<0.05);治疗7 d后,补阳还五汤组与抑制剂组相比,两组得分有明显差异(P<0.05);尼氏染色显示,标准模型组镜下脊髓神经元破坏明显,大量空洞样改变,神经元髓鞘脱落散乱,余各组镜下神经元损伤较轻;标准模型组较假手术组明显减少(P<0.05);补阳还五汤组与标准模型组比较,明显增多(P<0.05);抑制剂组较标准模型组明显增多(P<0.05),但与补阳还五汤组比,明显降低(P<0.05);在BDNF表达方面,标准模型组较假手术组降低(P<0.05),补阳还五汤组、抑制剂组较标准模型组有所升高(P<0.05);在TrkB表达方面,补阳还五汤组、抑制剂组较标准模型组降低(P<0.05),抑制剂组比补阳还五汤组降低(P<0.05);在PI3K/Akt表达方面,补阳还五汤组、抑制剂组较标准模型组升高(P<0.05)。结论补阳还五汤可通过BDNF/TrkB介导PI3K/Akt信号通路,促进神经元修复,对于脊髓神经元再生、修复以及运动功能的恢复都具有一定的促进作用。

Objective To explore the mechanism of Buyang Huanwu Decoction in against spinal cord neuronal apoptosis through the BDNF/TrkB-mediated PI3K/Akt signaling pathway.Methods 48 SD rats were randomly divided into the standard model group,Buyang Huanwu Decoction group,the inhibitor group,and the sham surgery group,with 12 rats in each group.The spinal cord of rats was injured using standard methods and the rats were treated continuously for 7 days.Modified Neuropathy Symptom Score(mNSS)was used to evaluate the neurological function of rats after treatment for 7 days.Using Nissl staining(NS),immunohistochemistry,and Western blotting(WB)to perform tissue sectioning,and detect the morphology of spinal cord neurons and the expression of BDNF and TrkB,PI3K/Akt in each group.Results After treatment,the mNSS scores on days 1,3,and 7 post-treatment for each group of rats were significantly reduced in the Buyang Huanwu Decoction group and the inhibitor group compared to the standard model group(P<0.05).After 7 days of treatment,there was a significant difference in scores between the Buyang Huanwu Decoction group and the inhibitor group(P<0.05).Nissl staining revealed that the spinal cord neurons in the standard model group exhibited significant damage,characterized by numerous hollow-like changes and scattered myelin sheaths.Neuron damage in the other groups was comparatively less severe.The standard model group had a significantly lower number of spinal cord neurons compared to the sham surgery group(P<0.05).The Buyang Huanwu Decoction group had a significantly higher neuron count than the standard model group(P<0.05).The inhibitor group had a significantly higher neuron count than the standard model group but a lower count than the Buyang Huanwu Decoction group(P<0.05).BDNF expression was lower in the standard model group than in the sham surgery group,while both the Buyang Huanwu Decoction group and the inhibitor group showed an increase compared to the standard model group(P<0.05).TrkB expression was lower in both the Buyang Huanwu Decoction group and the inhibitor group compared to the standard model group(P<0.05),with the inhibitor group showing a further reduction(P<0.05).PI3K/Akt expression was higher in both the Buyang Huanwu Decoction group and the inhibitor group compared to the standard model group(P<0.05).Conclusions Buyang Huanwu Decoction can promote neuronal repair through the BDNF/TrkB-mediated PI3K/Akt signaling pathway,and has a promoting effect on spinal cord neuronal regeneration,repair,and motor function recovery.