The number of papers about decavanadate has doubled in the past decade. In the present review, new insights into decavanadate biochemistry, cell biology, and antidiabetic and antitumor activities are described. Decame...The number of papers about decavanadate has doubled in the past decade. In the present review, new insights into decavanadate biochemistry, cell biology, and antidiabetic and antitumor activities are described. Decameric vanadate species (V10) clearly differs from monomeric vanadate (V1), and affects differently calcium pumps, and structure and function of myosin and actin. Only decavanadate inhibits calcium accumulation by calcium pump ATPase, and strongly inhibits actomyosin ATPase activity (IC50 = 1.4 μmol/L, V10), whereas no such ef- fects are detected with V1 up to 150 μmol/L; prevents actin polymerization (IC50 of 68 μmol/L, whereas no effects detected with up to 2 mmol/L V1); and interacts with actin in a way that induces cysteine oxidation and vanadate reduction to vanadyl. Moreover, in vivo decavanadate toxicity studies have revealed that acute exposure to polyoxovanadate induces different changes in antioxidant enzymes and oxidative stress parameters, in comparison with vanadate. In vitro studies have clearly demonstrated that mitochondrial oxygen consumption is strongly affected by decavanadate (IC50, 0.1 μmol/L); perhaps the most relevant biological effect. Finally, decavanadate (100 μmol/L) increases rat adipocyte glucose accumulation more potently than several vanadium complexes. Preliminary studies sug- gest that decavanadate does not have similar effects in human adipocytes. Although decavanadate can be a useful biochemical tool, further studies must be carried out before it can be conf irmed that decavanadate and its complexes can be used as anticancer or antidiabetic agents.展开更多
There is a growing body of evidence that Diabetes Mellitus leads to a specific cardiomyopathy apart from vascular disease and bring about high morbidity and mortality throughout the world.Recent clinical and experimen...There is a growing body of evidence that Diabetes Mellitus leads to a specific cardiomyopathy apart from vascular disease and bring about high morbidity and mortality throughout the world.Recent clinical and experimental studies have extensively demonstrated that this cardiomyopathy causes impaired cardiac performance manifested by early diastolic and late systolic dysfunction.This impaired cardiac performance most probably have emerged upon the expression and activity of regulatory proteins such as Na+/Ca2+exchanger,sarcoplasmic reticulum Ca2+-ATPase,ryanodine receptor and phospholamban.Over years many therapeutic strategies have been recommended for treatment of diabetic cardiomyopathy.Lately,inorganic elements have been suggested to have anti-diabetic effects due to their suggested ability to regulate glucose homeostasis,reduce oxidative stress or suppress phosphatases.Recent findings have shown that trace elements exert many biological effects including insulin-mimetic or antioxidant activity and in this manner they have been recommended as potential candidates for treatment of diabetes-induced cardiac complications,an effect based on their modes of action.Some of these trace elements are known to play an essential role as component of enzymes and thus modulate the organ function in physiological and pathological conditions.Besides,they can also manipulate redox state of the channels via antioxidant properties and thus contribute to the regulation of [Ca2+]i homeostasis and cardiac ion channels.On account of little information about some trace elements,we discussed the effect of vanadium,selenium,zinc and tungstate on diabetic heart complications.展开更多
Preliminary tests in rats have shown that the title complex is an efficient insulin mimic, which may be the first example of polyoxomatalates possessing insulin mimetic activity.
文摘The number of papers about decavanadate has doubled in the past decade. In the present review, new insights into decavanadate biochemistry, cell biology, and antidiabetic and antitumor activities are described. Decameric vanadate species (V10) clearly differs from monomeric vanadate (V1), and affects differently calcium pumps, and structure and function of myosin and actin. Only decavanadate inhibits calcium accumulation by calcium pump ATPase, and strongly inhibits actomyosin ATPase activity (IC50 = 1.4 μmol/L, V10), whereas no such ef- fects are detected with V1 up to 150 μmol/L; prevents actin polymerization (IC50 of 68 μmol/L, whereas no effects detected with up to 2 mmol/L V1); and interacts with actin in a way that induces cysteine oxidation and vanadate reduction to vanadyl. Moreover, in vivo decavanadate toxicity studies have revealed that acute exposure to polyoxovanadate induces different changes in antioxidant enzymes and oxidative stress parameters, in comparison with vanadate. In vitro studies have clearly demonstrated that mitochondrial oxygen consumption is strongly affected by decavanadate (IC50, 0.1 μmol/L); perhaps the most relevant biological effect. Finally, decavanadate (100 μmol/L) increases rat adipocyte glucose accumulation more potently than several vanadium complexes. Preliminary studies sug- gest that decavanadate does not have similar effects in human adipocytes. Although decavanadate can be a useful biochemical tool, further studies must be carried out before it can be conf irmed that decavanadate and its complexes can be used as anticancer or antidiabetic agents.
文摘There is a growing body of evidence that Diabetes Mellitus leads to a specific cardiomyopathy apart from vascular disease and bring about high morbidity and mortality throughout the world.Recent clinical and experimental studies have extensively demonstrated that this cardiomyopathy causes impaired cardiac performance manifested by early diastolic and late systolic dysfunction.This impaired cardiac performance most probably have emerged upon the expression and activity of regulatory proteins such as Na+/Ca2+exchanger,sarcoplasmic reticulum Ca2+-ATPase,ryanodine receptor and phospholamban.Over years many therapeutic strategies have been recommended for treatment of diabetic cardiomyopathy.Lately,inorganic elements have been suggested to have anti-diabetic effects due to their suggested ability to regulate glucose homeostasis,reduce oxidative stress or suppress phosphatases.Recent findings have shown that trace elements exert many biological effects including insulin-mimetic or antioxidant activity and in this manner they have been recommended as potential candidates for treatment of diabetes-induced cardiac complications,an effect based on their modes of action.Some of these trace elements are known to play an essential role as component of enzymes and thus modulate the organ function in physiological and pathological conditions.Besides,they can also manipulate redox state of the channels via antioxidant properties and thus contribute to the regulation of [Ca2+]i homeostasis and cardiac ion channels.On account of little information about some trace elements,we discussed the effect of vanadium,selenium,zinc and tungstate on diabetic heart complications.
基金Supported by the National Natural Science Foundation of China(No. 30 1710 11)
文摘Preliminary tests in rats have shown that the title complex is an efficient insulin mimic, which may be the first example of polyoxomatalates possessing insulin mimetic activity.
