摘要
目的 :建立β淀粉样蛋白 (Aβ)所致的神经细胞毒模型 ,探讨调心方的药效及作用机理。 方法 :原代培养大鼠海马神经元 ,用 2 5 μmol/L聚集状态的Aβ1 4 2建立神经细胞毒模型。采用乳酸脱氢酶(LDH)释放量来检测神经元存活率 ,通过透射电镜、流式细胞仪检测判断神经元凋亡 ,应用免疫细胞化学法研究凋亡相关基因的表达蛋白 (Bcl 2、Bax、c Jun)。结果 :神经元经Aβ1 4 2处理后 ,LDH释放增加 ;电镜显示细胞体积缩小、染色质固缩、或浓聚成块状位于核周边、滑面内质网扩张 ;流式细胞仪检测可见亚二倍体峰 ;Bcl 2减少 ,而Bax与c Jun增加。调心方使LDH释放减少 ,电镜下具有凋亡形态特征的细胞减少 ,流式细胞仪检测显示凋亡率下降 ,Bcl 2增加 ,Bax减少 ,而c Jun变化不明显。四氢氨基吖啶 (THA)组神经元存活率增加 ,但其他指标的变化不明显。结论 :调心方对Aβ1 4 2神经细胞毒有保护作用 ,可提高细胞存活率 ,抑制凋亡 ,其抑制凋亡作用的机制可能是通过提高bcl 2、降低bax基因的蛋白表达而实现。THA对神经元存活率有提高作用 ,但抑制神经元凋亡的作用似不明显。调心方对抑制Aβ所致神经元凋亡明显优于THA。
Objective: To study the effect of Tiaoxin Recipe (TXR) on β amyloid induced neurotoxicity in the primary cultured hippocampal neurons and the therapeutical mechanism of it. Methods: In order to establish neurotoxic model ,the primary cultured rat hippocampal neurons were treated with 25μmol/L aggregated β amyloid fragment 1 42 (Aβ1 42). Neuronal survival was assessed by lactate dehydrogenase (LDH) activity . Apoptosis of neurons was determined with transmission electron microscopy (TEM) examination and flowcytometric analysis. The protein expression of apoptosis associated gene (Bcl 2, Bax, c Jun) were examined by using immunocytochemical SABC method. Results: In the Aβ1 42 treated neurons, the release of LDH was increased, TEM examination revealed that the cell body became shrunken, the chromatin was compacted or the patches of condensed chromatin lay against the nuclear membrane and the smooth surfaced endoplasmic reticulum was expanded. Flowcytometric analysis displayed the peak of hypodiploid DNA content. The expression of Bcl 2 was lowered, while Bax and c Jun protein were increased. After treated with TXR, the above mentioned changes were improved with the exception of c Jun expression. In the Tacrine treated group, only the neuronal survival was increased, other observed criteria had insignificant change. Conclusion: TXR could attenuate the neurotoxic action of Aβ1 42 and improve neuronal survival via suppressing apoptotic process. TXR could inhibit the apoptotic process via regulating the expression of bcl 2 and bax. Tacrine could improve neuronal survival, but its inhibition on neuronal apoptosis was not significant.
出处
《中国中西医结合杂志》
CAS
CSCD
北大核心
2001年第9期674-676,共3页
Chinese Journal of Integrated Traditional and Western Medicine
基金
国家自然科学基金重点项目 (No.39830 4 50 )
上海市教委科技发展基金 (No.98CJ0 1 )资助
关键词
Β淀粉样蛋白
调心方
神经元凋亡
凋亡相关基因表达
amyloid protein, Tiaoxin Recipe, neuronal apoptosis, apoptosis associated gene expression
