Glutathione （GSH） is a tripeptide that constitutes one of the main intracellular reducing compounds. The normal content of GSH in the intestine is essential to optimize the intestinal Ca2＋ absorption. The use of GS...Glutathione （GSH） is a tripeptide that constitutes one of the main intracellular reducing compounds. The normal content of GSH in the intestine is essential to optimize the intestinal Ca2＋ absorption. The use of GSH depleting drugs such as DL-buthionine-S,R-sulfoximine, menadione or vitamin K3, sodium deoxycholate or diets enriched in fructose, which induce several features of the metabolic syndrome, produce inhibition of the intestinal Ca2＋ ab-sorption. The GSH depleting drugs switch the redox state towards an oxidant condition provoking oxida-tive/nitrosative stress and inflammation, which lead to apoptosis and/or autophagy of the enterocytes. Either the transcellular Ca transport or the paracellular Ca route are altered by GSH depleting drugs. The gene and/or protein expression of transporters involved in the transcellular Ca2＋ pathway are decreased. The favonoids quercetin and naringin highly abrogate the inhibition of intestinal Ca2＋ absorption, not only by restoration of the GSH levels in the intestine but also by their anti-apoptotic properties. Ursodeoxycholic acid, melatonin and glutamine also block the inhibition of Ca2＋ transport caused by GSH depleting drugs. The use of any of these antioxidants to ameliorate the intestinal Ca2＋ absorption under oxidant conditions associated with different pathologies in humans requires more investigation with regards to the safety,pharmacokinetics and pharmacodynamics of them.展开更多
Salvianolic acid B(Sal B) is an active component of traditional Chinese medicine Salvia miltiorrhiza and is used to treat vascular diseases. To better understand its mechanism, the antioxidant capacities of Sal B was ...Salvianolic acid B(Sal B) is an active component of traditional Chinese medicine Salvia miltiorrhiza and is used to treat vascular diseases. To better understand its mechanism, the antioxidant capacities of Sal B was evaluated with human endothelial cells under oxidative stress. Human endothelial cells were pretreated with Sal B for 12 h followed by hydrogen peroxide for another 12 h. Production of reactive oxygen species (ROS), activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), and concentration of glu-tathione were measured. Protective effect of Sal B on the endothelial cells from hydrogen peroxide-induced damage was observed, and ROS production in the cells was found significantly inhibited. Sal B remarkably enhanced the activities of antioxidant enzymes SOD, CAT and GPX. Furthermore, Sal B up-regulated the intracellular glu-tathione concentration. The results indicate that Sal B protected endothelial cells from oxidative stress by improving the redox status of the cells through enhancing the antioxidant enzyme activities and increasing the reductive glu-tathione concentration after the oxidative challenge.展开更多
文摘Glutathione （GSH） is a tripeptide that constitutes one of the main intracellular reducing compounds. The normal content of GSH in the intestine is essential to optimize the intestinal Ca2＋ absorption. The use of GSH depleting drugs such as DL-buthionine-S,R-sulfoximine, menadione or vitamin K3, sodium deoxycholate or diets enriched in fructose, which induce several features of the metabolic syndrome, produce inhibition of the intestinal Ca2＋ ab-sorption. The GSH depleting drugs switch the redox state towards an oxidant condition provoking oxida-tive/nitrosative stress and inflammation, which lead to apoptosis and/or autophagy of the enterocytes. Either the transcellular Ca transport or the paracellular Ca route are altered by GSH depleting drugs. The gene and/or protein expression of transporters involved in the transcellular Ca2＋ pathway are decreased. The favonoids quercetin and naringin highly abrogate the inhibition of intestinal Ca2＋ absorption, not only by restoration of the GSH levels in the intestine but also by their anti-apoptotic properties. Ursodeoxycholic acid, melatonin and glutamine also block the inhibition of Ca2＋ transport caused by GSH depleting drugs. The use of any of these antioxidants to ameliorate the intestinal Ca2＋ absorption under oxidant conditions associated with different pathologies in humans requires more investigation with regards to the safety,pharmacokinetics and pharmacodynamics of them.
基金Supported by National Natural Science Foundation of China (No30873400)Natural Science Foundation of Tianjin (No06YFJMC07300)
文摘Salvianolic acid B(Sal B) is an active component of traditional Chinese medicine Salvia miltiorrhiza and is used to treat vascular diseases. To better understand its mechanism, the antioxidant capacities of Sal B was evaluated with human endothelial cells under oxidative stress. Human endothelial cells were pretreated with Sal B for 12 h followed by hydrogen peroxide for another 12 h. Production of reactive oxygen species (ROS), activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), and concentration of glu-tathione were measured. Protective effect of Sal B on the endothelial cells from hydrogen peroxide-induced damage was observed, and ROS production in the cells was found significantly inhibited. Sal B remarkably enhanced the activities of antioxidant enzymes SOD, CAT and GPX. Furthermore, Sal B up-regulated the intracellular glu-tathione concentration. The results indicate that Sal B protected endothelial cells from oxidative stress by improving the redox status of the cells through enhancing the antioxidant enzyme activities and increasing the reductive glu-tathione concentration after the oxidative challenge.
