Williams Zakia R, Goodman Carl B, Soliman Karam F A
College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA.
Neurochem Res. 2007 Jun;32(6):1071-80. doi: 10.1007/s11064-006-9276-7. Epub 2007 Mar 31.
The neurotoxin 1-methy-4-phenylpyridinium (MPP(+)) is used for its' capacity to induce Parkinsonism through its inhibitory effects on mitochondrial complex I. This inhibition disrupts cellular energy formation and aerobic glycolysis. The objective of this study was to demonstrate that the toxic effect of mitochondrial aerobic pathway inhibition with MPP(+ )can be reduced by stimulating anaerobic glycolysis using glucose supplementation. In this study, C6 Glioma cell viability was examined in the presence of different concentrations of MPP alone and with the addition of glucose. The results obtained indicate that there was a significant increase (P < 0.001) in cell viability in cells treated with glucose and MPP(+ )verses cells treated with MPP(+ )alone. Fluorometric analysis using 100 microM Rhodamine 123 indicated mitochondrial membrane potential was not restored in MPP(+ )treated cells with glucose; however, normal cell viability was confirmed using 2 microg/ml Fluorescein diacetate. This dual fluorescence indicated mitochondrial damage from MPP(+ )while glucose augmented cell survival. Further confirmation of cell survival upon damage to the mitochondria was evident in TUNEL staining. Positive staining was prominent only in MPP(+) treatment groups alone, while control and co-treated groups exhibited little to no TUNEL staining. ATP measurements of all MPP(+) treated groups exhibited a significant (P < 0.001) decrease verses control. Groups co-treated with MPP(+ )and glucose revealed a significant increase (250 microM group: P < 0.001) in ATP. It was concluded from this study that glucose supplementation was able to sustain cellular viability and ATP production through anaerobic glycolysis despite the inhibitory effect of MPP(+ )on aerobic glycolysis.
神经毒素1-甲基-4-苯基吡啶鎓（MPP(+)）因其对线粒体复合物I的抑制作用而被用于诱导帕金森症。这种抑制作用会破坏细胞能量生成和有氧糖酵解。本研究的目的是证明通过补充葡萄糖刺激无氧糖酵解可以降低MPP(+)对线粒体有氧途径的抑制毒性作用。在本研究中，检测了单独使用不同浓度MPP以及添加葡萄糖时C6胶质瘤细胞的活力。所得结果表明，与单独用MPP(+)处理的细胞相比，用葡萄糖和MPP(+)处理的细胞活力显著增加（P < 0.001）。使用100微摩尔罗丹明123的荧光分析表明，在用葡萄糖处理的MPP(+)细胞中线粒体膜电位未恢复；然而，使用2微克/毫升荧光素二乙酸酯证实了细胞活力正常。这种双重荧光表明MPP(+)造成了线粒体损伤，而葡萄糖增强了细胞存活能力。TUNEL染色进一步证实了线粒体受损后细胞的存活情况。仅在单独的MPP(+)处理组中阳性染色明显，而对照组和联合处理组几乎没有或没有TUNEL染色。所有MPP(+)处理组的ATP测量结果与对照组相比均显著降低（P < 0.001）。MPP(+)与葡萄糖联合处理的组中ATP显著增加（250微摩尔组：P < 0.001）。本研究得出的结论是，尽管MPP(+)对有氧糖酵解有抑制作用，但补充葡萄糖能够通过无氧糖酵解维持细胞活力和ATP生成。
