Human Bcl-2 protects against AMPA receptor-mediated apoptosis
Human Bcl-2 protects against AMPA receptor-mediated apoptosis
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DOI：
10.1046/j.1471-4159.2000.0741613.x
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发表时间：
2000-04-01
影响因子：
4.7
通讯作者：
Bernard, O
中科院分区：
文献类型：
--
作者：
Cheung, NS;Beart, PM;Bernard, O
脑主要兴奋性神经递质L-谷氨酸盐的离子型受体（AMPA）亚型的（S）-α-氨基-3-羟基-5-甲基异恶唑-4-丙酸酯（AMPA）功能障碍发生在各种神经病症中。我们以前已经证明，AMPA受体介导的兴奋性毒性发生的细胞凋亡，并在这里检查细胞死亡阻遏基因Bcl-2的表达对这种兴奋性毒性损伤的影响。使用从表达人Bcl-2基因的转基因小鼠制备的神经元皮层培养物，将Bcl-2对AMPA受体介导的神经元死亡的影响与用星形孢菌素和H2 O2观察到的影响进行比较。在第6天，将培养物暴露于AMPA（0.1-100 μ M），并在损伤后48小时使用相差显微镜、3-（4，5-二甲基噻唑-2-基）-2，5-二苯基溴化四唑鎓活力测定和用4，6-二脒基-2-苯基吲哚和Sytox绿色进行DNA染色来分析细胞损伤。AMPA产生的细胞死亡的浓度依赖性增加，这是显着减弱人Bcl-2。AMPA（3 μ M）增加了野生型培养物中的凋亡细胞核的数量至对照的60%，而人Bcl-2显着降低了AMPA处理的培养物中的凋亡细胞核的数量至30%。人Bcl-2仅对由两种浓度的星形孢菌素（1-10 nM）和H2 O2（0.1-30 μ M）诱导的神经元损伤提供显著的神经保护，其中神经元死亡是通过细胞凋亡，但对H2 O2诱导的坏死不提供保护。我们的研究结果表明，Bcl-2在原代培养的神经元中的过表达保护在一个依赖于AMPA受体介导的细胞凋亡的方式，而保护没有看到更多的创伤性损伤。这项研究为神经退行性疾病的分子治疗提供了新的见解。
Dysfunctions of the (S)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) subtype of ionotropic receptor for the brain's major excitatory neurotransmitter, L-glutamate, occur in various neurological conditions. We have previously demonstrated that AMPA receptor-mediated excitotoxicity occurs by apoptosis and here examined the influence of the expression of cell death repressor gene Bcl-2 on this excitotoxic insult. Using neuronal cortical cultures prepared from transgenic mice expressing the human Bcl-2 gene, the influence of Bcl-2 on AMPA receptor-mediated neuronal death was compared with that seen with staurosporine and H2O2. At day 6 cultures were exposed to AMPA (0.1-100 mu M), and cellular injury was analyzed 48 h after insult using phase-contrast microscopy, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide viability assay, and DNA staining with 4,6-diamidino-2-phenylindole and Sytox Green. AMPA produced a concentration-dependent increase in cell death that was significantly attenuated by human Bcl-2. AMPA (3 mu M) increased the number of apoptotic nuclei to 60% of control in wild-type cultures, and human Bcl-2 significantly decreased the number of apoptotic nuclei to 30% of AMPA-treated cultures. Human Bcl-2 only provided significant neuroprotection against neuronal injury induced by tow concentrations of staurosporine (1-10 nM) and H2O2 (0.1-30 mu M) and where neuronal death was by apoptosis, but not against H2O2-induced necrosis. Our findings indicate that overexpression of Bcl-2 in primary cultured neurons protects in an insult-dependent manner against AMPA receptor-mediated apoptosis, whereas protection was not seen against more traumatic insults. This study provides new insights into the molecular therapeutics of neurodegenerative conditions.