著者
高橋 恭兵 立浪 良介 丹保 好子
出版者
公益社団法人 日本薬学会
雑誌
YAKUGAKU ZASSHI (ISSN:00316903)
巻号頁・発行日
vol.128, no.10, pp.1443-1448, 2008 (Released:2008-10-01)
参考文献数
33
被引用文献数
7 11

Diabetic patients exhibit increased blood plasma levels of methylglyoxal (MG), a metabolite of glucose. Since MG generates advanced glycation end-products (AGEs) that disrupt the functions of such biomolecules as proteins, it is responsible for the progression and complications of diabetes. A functional disorder of the vascular endothelium may also contribute to the progression and complications of diabetes. In endothelial cells, MG is the major precursor for the formation of AGEs. In this study, we examined the effects of MG on vascular endothelial cells and found that it induced the apoptosis of bovine aortic endothelial cells (BAECs). MG induced the collapse of mitochondrial membrane potential, an index of apoptosis, and the elevation of caspase-3 activity, an apoptotic execution enzyme, leading to cell death. Flow cytometric analyses with annexin-V and propidium iodide double staining revealed that cells exposed to a lethal dose of MG displayed features characteristic of apoptosis. MG induced an increase in the level of intracellular reactive oxygen species (ROS) prior to induction of apoptosis. Taken together, these findings suggest that BAECs exposed to MG die by apoptosis due to the increase of intracellular ROS level.
著者
立浪 良介 高橋 恭兵 大場 達也 丹保 好子
出版者
公益社団法人 日本薬学会
雑誌
YAKUGAKU ZASSHI (ISSN:00316903)
巻号頁・発行日
vol.129, no.1, pp.147-153, 2009 (Released:2009-01-01)
参考文献数
32
被引用文献数
2 6

Methylglyoxal (MG), a highly reactive dicarbonyl compound, is a metabolic by-product of glycolysis. MG is often detected at high levels in the blood of diabetic patients. We examined whether MG was capable of inducing reactive oxygen species (ROS) production in bovine aortic endothelial cells (BAECs). The viability of BAECs decreased with time on treatment with 5 mM MG, and was almost completely lost at 24 h. In contrast, MG at 1 mM had little influence on BAEC viability up to 24 h, but induced the elevation of intracellular glutathione content at 24 h. Exposure of BAECs to MG caused a dose-dependent increase in oxidized-hydroethidine fluorescence intensity, indicating ROS production. In addition, aconitase inactivation, which is an indicator of intracellular superoxide, was observed in MG-treated cells. Finally, we found that MG at 5 mM increased the fluorescence intensity of BES-So, a specific probe for superoxide. Together, the results suggest that MG induces superoxide production in endothelial cells, and that the accumulation of ROS may be linked to cytotoxic effects.