Pentavalent vanadium (V5+) (metavanadate salt) tox- icity is a challenging problem to the health professionals and has been recognized as an industrial hazard that adversely affects human and animal health, but its cy...Pentavalent vanadium (V5+) (metavanadate salt) tox- icity is a challenging problem to the health professionals and has been recognized as an industrial hazard that adversely affects human and animal health, but its cytotoxic mechanisms have not yet been completely understood. In this study, we investigated the cytotoxic mechanisms of V5+ in freshly isolated rat hepatocytes. V5+ cytotoxicity was associated with reactive oxygen species (ROS) formation, collapse of mitochondrial membrane potential, lysosomal membrane rupture and cytochrome c release into the hepatocyte cytosol. All of the above mentioned V5+ -induced cytotoxicity markers were significantly (p 5+ is activated by GSH. Our findings also showed that the lysosomotropic agents prevented V5+ induced mitochondrial membrane potential collapse. On the other hand, mitochondrial MPT pore sealing agents inhibited lysosomal membrane damage caused by V5+. It can therefore be suggested that there is probably a toxic interaction (cross-talk) between mitochondrial and lysosomal oxidative stress generating systems, which potentiates ROS formation and further damages both sub-organelles in V5+-induced induced hepatotoxicity. In conclusion, V5+-induced cytotoxicity can be attributed to oxidative stress started from glutathione mediated metal reductive activation and continued by mitochondrial/lysosomal toxic interaction.展开更多
在不同的钒（V）胁迫浓度（0、25、50、100和200 mg＆#183; kg -1）条件下，通过40 d盆栽试验，研究了枸杞植株对V积累及V对枸杞叶中细胞膜透性、抗氧化酶活性，以及丙二醛（ MDA）、脯氨酸（ Pro）、叶绿素和可溶性蛋白含量的影响。结...在不同的钒（V）胁迫浓度（0、25、50、100和200 mg＆#183; kg -1）条件下，通过40 d盆栽试验，研究了枸杞植株对V积累及V对枸杞叶中细胞膜透性、抗氧化酶活性，以及丙二醛（ MDA）、脯氨酸（ Pro）、叶绿素和可溶性蛋白含量的影响。结果表明，枸杞中各部位V含量分布大小的顺序依次为根＞叶＞茎。随着V浓度增大，过氧化氢酶（CAT）和过氧化物酶（POD）活性、叶绿素含量和可溶性蛋白含量等呈先上升、后下降的变化趋势，当 V 胁迫浓度≤100 mg ＆#183; kg -1时，与对照组相比， CAT和POD的活性、叶绿素含量和可溶性蛋白含量分别增大了227.9％、76.2％、40.2％和117.4％；当V胁迫浓度＞100 mg＆#183; kg -1，则分别降低了5.1％、5.8％、22.8％和36.7％。在不同浓度V的处理下， MDA含量、细胞膜透性和 Pro 含量比对照分别增加了13.3％～220.7％、12.4％～76.9％和69.7％～276.3％。可见，低浓度V （＜100 mg＆#183; kg -1）刺激了叶绿素和抗氧化酶活性的增加，促进了植物可溶性蛋白质的合成；高浓度V （≥100 mg ＆#183; kg-1）破坏了叶绿素结构，抑制了抗氧化酶和可溶性蛋白的合成，膜脂过氧化作用和细胞膜透性显著增大，游离脯氨酸含量明显增加。展开更多
文摘Pentavalent vanadium (V5+) (metavanadate salt) tox- icity is a challenging problem to the health professionals and has been recognized as an industrial hazard that adversely affects human and animal health, but its cytotoxic mechanisms have not yet been completely understood. In this study, we investigated the cytotoxic mechanisms of V5+ in freshly isolated rat hepatocytes. V5+ cytotoxicity was associated with reactive oxygen species (ROS) formation, collapse of mitochondrial membrane potential, lysosomal membrane rupture and cytochrome c release into the hepatocyte cytosol. All of the above mentioned V5+ -induced cytotoxicity markers were significantly (p 5+ is activated by GSH. Our findings also showed that the lysosomotropic agents prevented V5+ induced mitochondrial membrane potential collapse. On the other hand, mitochondrial MPT pore sealing agents inhibited lysosomal membrane damage caused by V5+. It can therefore be suggested that there is probably a toxic interaction (cross-talk) between mitochondrial and lysosomal oxidative stress generating systems, which potentiates ROS formation and further damages both sub-organelles in V5+-induced induced hepatotoxicity. In conclusion, V5+-induced cytotoxicity can be attributed to oxidative stress started from glutathione mediated metal reductive activation and continued by mitochondrial/lysosomal toxic interaction.
文摘在不同的钒（V）胁迫浓度（0、25、50、100和200 mg＆#183; kg -1）条件下，通过40 d盆栽试验，研究了枸杞植株对V积累及V对枸杞叶中细胞膜透性、抗氧化酶活性，以及丙二醛（ MDA）、脯氨酸（ Pro）、叶绿素和可溶性蛋白含量的影响。结果表明，枸杞中各部位V含量分布大小的顺序依次为根＞叶＞茎。随着V浓度增大，过氧化氢酶（CAT）和过氧化物酶（POD）活性、叶绿素含量和可溶性蛋白含量等呈先上升、后下降的变化趋势，当 V 胁迫浓度≤100 mg ＆#183; kg -1时，与对照组相比， CAT和POD的活性、叶绿素含量和可溶性蛋白含量分别增大了227.9％、76.2％、40.2％和117.4％；当V胁迫浓度＞100 mg＆#183; kg -1，则分别降低了5.1％、5.8％、22.8％和36.7％。在不同浓度V的处理下， MDA含量、细胞膜透性和 Pro 含量比对照分别增加了13.3％～220.7％、12.4％～76.9％和69.7％～276.3％。可见，低浓度V （＜100 mg＆#183; kg -1）刺激了叶绿素和抗氧化酶活性的增加，促进了植物可溶性蛋白质的合成；高浓度V （≥100 mg ＆#183; kg-1）破坏了叶绿素结构，抑制了抗氧化酶和可溶性蛋白的合成，膜脂过氧化作用和细胞膜透性显著增大，游离脯氨酸含量明显增加。
