摘要
目的基于血管内皮生长因子(VEGF)介导的磷脂酰肌醇-3激酶(PI3K)/蛋白激酶B(Akt)信号通路,探讨地黄饮子对血管性痴呆(VD)模型大鼠的神经保护作用。方法取60只SD雄性大鼠,按随机原则选择10只大鼠作为假手术组,其余50只大鼠采用两血管阻断(2-VO)法制备VD模型,采用神经功能缺损Zea-Longa5级4分制评分方法筛选成模大鼠。将45只造模成功大鼠随机分为5组,每组9只。地黄饮子高、中、低剂量组分别给予3 g/kg、1.5 g/kg、0.75 g/kg地黄饮子汤灌胃,尼莫地平组给予6.25 mg/kg尼莫地平混悬液灌胃,假手术组和模型组给予等体积生理盐水灌胃,均1次/d。连续灌胃30 d后,采用Zea-Longa评分评估大鼠神经功能,以Morris水迷宫检测大鼠学习记忆能力,HE染色观察皮质区神经元形态结构,Western blot法检测脑组织中磷酸化磷脂酰肌醇3-激酶(p-PI3K)、磷酸化蛋白激酶B(p-Akt)、B淋巴细胞瘤-2基因(Bcl-2)、Bcl-2相关X蛋白(Bax)、VEGF受体2(VEGFR2)蛋白表达情况。结果与假手术组比较,模型组大鼠Zea-Longa评分明显升高(P<0.05),第3~5天的逃避潜伏期均明显延长(P均<0.05),穿梭有效区次数明显减少(P<0.05),皮质区神经元形态结构受损,脑组织中p-PI3K、p-Akt、Bcl-2蛋白相对表达量均明显降低(P均<0.05),Bax蛋白相对表达量明显升高(P<0.05)。与模型组比较,各药物组大鼠Zea-Longa评分均明显降低(P均<0.05),第3~5天的逃避潜伏期均明显缩短(P均<0.05),穿梭有效区次数明显增加(P均<0.05),皮质区神经元形态结构受损情况得到改善,地黄饮子中剂量组、地黄饮子低剂量组脑组织中p-PI3K、p-Akt、Bcl-2蛋白相对表达量,尼莫地平组p-PI3K及p-Akt蛋白相对表达量和地黄饮子中剂量组VEGFR2蛋白相对表达量均明显升高(P均<0.05),尼莫地平组、地黄饮子中剂量组、地黄饮子低剂量组Bax蛋白相对表达量均明显降低(P均<0.05);各药物组间各指标比较差异均无统计学意义(P均>0.05)。结论地黄饮子可以减轻VD大鼠皮质区神经元损伤,促进血管新生,抑制细胞凋亡,以改善VD大鼠神经功能和学习记忆能力,机制可能与VEGF介导的PI3K/Akt信号通路有关。
Objective It is to investigate the neuroprotective effect of Dihuang Decoction on vascular dementia(VD)model rats based on phosphatidylinositol-3-kinase(PI3K)/protein kinase B(Akt)signaling pathway mediated by vascular endothelial growth factor(VEGF).Methods Sixty SD male rats were taken,in which 10 rats were randomly selected as sham operation group,and the remaining rats were used to establish VD models by 2-VO method.The modeling rats were screened by the method of Zea-Longa 5-grade 4-point scoring for neurological deficits.45 successfully modeled rats were randomly divided into 5 groups,with 9 rats in each group.The high,medium and low dose groups of Rehmannia Decoction were respectively given Rehmannia Decoction 3 g/kg,1.5 g/kg and 0.75 g/kg by gavage,the nimodipine group was given nimodipine suspension 6.25 mg/kg by gavage,and the sham operation group and model group were given equal volumes of saline by gavage,all once daily.After 30 days of consecutive gavage,the neural function of the rats was assessed by Zea-Longa scores,the learning and memory abilities of the rats were detected by Morris water maze,the morphology and structure of neurons in cortical areas were observed by HE staining,and the protein expressions of phosphorylated phosphatidylinositol 3-kinase(p-PI3K),phosphorylated protein kinase B(p-Akt),B-lymphoblastoma-2 gene(Bcl-2),Bcl-2-related X protein(Bax),VEGF receptor 2(VEGFR2)were detected by Western blot.Results Compared with the sham operation group,the Zea-Longa scores of rats in the model group were significantly increased(P<0.05),the escape latency from the 3rd day to 5 th day were all significantly prolonged(all P<0.05),the times of crossing the effective area were significantly reduced(P<0.05),the morphology and structure of neurons in cortical areas were impaired,and the relative expressions of p-PI3K,p-Akt,and Bcl-2 proteins in the brain tissues were significantly reduced(all P<0.05),and the relative expression of Bax protein was significantly increased(P<0.05).Compared with the model group,the Zea-Longa scores of rats in each treatment group were significantly decreased(all P<0.05),the escape latency from the 3rd day to 5 th day were all significantly shortened(all P<0.05),the times of crossing the effective area were significantly increased(P<0.05),the injury of morphology and structure of neurons in cortical areas were improved,and the relative expressions of p-PI3K,p-Akt,and Bcl-2 proteins in the brain tissues of the medium and low dose groups of Rehmannia Decoction,the relative expressions of p-PI3K,p-Akt proteins in the brain tissues of nimodiping group,and the relative expression of VEGFR2 protein of the medium dose group of Rehmannia Decoction were all significantly increased(all P<0.05),and the relative expressions of Bax protein of nimodiping group,medium and low dose groups of Rehmannia Decoction were significantly decreased(P<0.05),there was no significant difference in these indexes among every treatment group(all P>0.05).Conclusion Rehmannia Decoction can alleviate neuronal injury,promote angiogenesis and inhibit apoptosis in the cortical area of VD rats,thus to improve their neurological function and learning and memory abilities,the mechanism may be related to VEGF-mediated PI3K/Akt signaling pathway.
作者
李晓宁
彭孟凡
周雨慧
LI Xiaoning;PENG Mengfan;ZHOU Yuhui(Tangshan Hospital of Traditional Chinese Medicine,Tangshan 063000,Hebei,China;School of Medicine of Huanghuai University,Zhumadian 463003,Henan,China)
出处
《现代中西医结合杂志》
CAS
2024年第14期1935-1940,1945,共7页
Modern Journal of Integrated Traditional Chinese and Western Medicine
基金
河北省中医药管理局科研计划项目(2023195)
河南省科技攻关项目(242102310523)。
作者简介
李晓宁,男,硕士,主治中医师,研究方向为中医药防治内科疾病;通信作者:周雨慧,E-mail:826757706@qq.com。
