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Félix Alexandre Antunes Soares - One of the best experts on this subject based on the ideXlab platform.
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An Organotellurium Compound with antioxidant activity against excitotoxic agents without neurotoxic effects in brain of rats.
Brain research bulletin, 2008Co-Authors: Daiana Silva Ávila, Priscila Gubert, Aline Palma, Dirleise Colle, Diego Alves, Cristina Wayne Nogueira, João Batista Teixeira Rocha, Félix Alexandre Antunes SoaresAbstract:The glutamatergic system is an important target in many neurodegenerative diseases and for several neurotoxic drugs. Organotellurium Compounds are often very good free radical scavengers' agents. Recently, we reported that diethyl-2-phenyl-2-tellurophenyl vinylphosphonate is a Compound with low toxicity in vitro and in vivo, as well as also possesses antioxidant activity against iron-induced lipid peroxidation. The aim of this study was to evaluate in vitro the antioxidant and mitochondrial protective effect of this Organotellurium Compound against quinolinic acid (QA) and sodium nitroprusside (SNP), and to evaluate the in vitro actions of this Organotellurium Compound in the glutamatergic system in brain of rats. We observed that the telluro vinylphosphonate possess an antioxidant activity against QA and SNP at micromolar concentrations. When tested at antioxidant concentrations (from 2 to 10muM), the Compound does not affect the mitochondrial viability and [3H]glutamate uptake in slices from cerebral cortex, hippocampus and striatum, [3H]glutamate release from synaptosomal preparations and [3H]glutamate binding in membrane preparation. Our data suggest that the telluro vinylphosphonate act as an antioxidant in the central nervous system in vitro with no effects on the glutamatergic system; nevertheless more studies in different models of brain injury must be performed in order to corroborate our findings.
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A biochemical and toxicological study with diethyl 2-phenyl-2-tellurophenyl vinylphosphonate in a sub-chronic intraperitoneal treatment in mice.
Life sciences, 2007Co-Authors: Daiana Silva Ávila, Cristina W. Nogueira, João Rocha, Priscila Gubert, Diego Alves, Cristiane L. Dalla Corte, Félix Alexandre Antunes SoaresAbstract:Diethyl-2-phenyl-2-tellurophenyl vinylphosphonate (DPTVP) is an Organotellurium Compound with low toxicity after subcutaneous administration in mice. This study evaluated possible in vivo and ex vivo toxicological effects of daily injections of DPTVP for 12 days in mice, using the intraperitoneal administration. This route potentially increases the pharmacokinetics of absorption, distribution, metabolism and toxicity of DPTVP. Treatment with DPTVP (0, 30, 50, 75, 100, 250, 350 or 500 micromol/kg) were not associated with mortality or body weight loss. Nevertheless, the liver and liver-to-body weight ratio increased in groups treated with 350 and 500 micromol/kg of DPTVP. However, plasmatic aspartate and alanine aminotransferase activities (classical markers of hepatotoxicity) were not increased after diethyl-2-phenyl-2-tellurophenyl vinylphosphonate administration. Hepatic, renal and cerebral thiobarbituric acid reactive substances (TBARS), delta-ALA-D activity and Vitamin C levels were not modified after DPTVP treatment. Renal and hepatic superoxide dismutase (SOD) and catalase (CAT) were unchanged after DPTVP treatment. Conversely, SOD activity significantly increased in brain in groups treated with 50, 75, 100 and 500 micromol/kg of DPTVP treated groups. Our findings corroborates that brain is a potential target for organochalcogen action. The absence of severe overt signs of toxicity after sub-chronic exposure to DPTVP reinforces the necessity for more detailed pharmacological studies concerning this new Organotellurium Compound.
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Diethyl 2-phenyl-2 tellurophenyl vinylphosphonate: an Organotellurium Compound with low toxicity.
Toxicology, 2006Co-Authors: Daiana Silva Ávila, Marisa C. Beque, Vanderlei Folmer, Antonio L. Braga, Gilson Zeni, Cristina W. Nogueira, Félix Alexandre Antunes Soares, João RochaAbstract:It is well-known that Organotellurium Compounds can have antioxidant activity in vitro, but in vivo these Compounds can be potentially toxic to rodents. Here we investigated the potential in vitro and ex vivo toxicity of a new beta-organochalcogenyl vinylphosphonate, the diethyl 2-phenyl-2 tellurophenyl vinylphosphonate. The in vitro antioxidant activity of this Organotellurium Compound was also investigated. In vitro, the rate of dithiotreitol (DTT) oxidation was increased and the activity of cerebral, renal and hepatic delta-aminolevulinate dehydratase (delta-ALA-D) was decreased by diethyl 2-phenyl-2-tellurophenyl vinylphosphonate (120-1200 microM), indicating that this Compound oxidize-SH groups. The antioxidant activity was also observed in brain, liver and kidney, in very low concentrations (0.4, 1.0, 4.0, 10.0 and 40.0 microM), and this capacity was comparable to the antioxidant standard Organotellurium Compound, diphenyl ditelluride. In vivo, delta-ALA-D activity in liver, kidney and brain of mice treated for 12 days with dimethylsulfoxide (DMSO) as vehicle, 25, 75 or 250 micromol/kg of diethyl 2-phenyl-2-tellurophenyl vinylphosphonate was not affected. Furthermore, only one animal treated with the highest dose died, whereas all animals treated with diphenyl ditteluride died in the fourth day. These results suggest that this novel Organotellurium Compound interacts with the sulfhydryl groups, however only at higher doses when compared with diphenyl ditelluride. Since diethyl 2-phenyl-2 tellurophenyl vinylphosphonate had low toxicity to mice after sub-chronic exposure, it becomes important to investigate its possible pharmacological properties.
Daiana Silva Ávila - One of the best experts on this subject based on the ideXlab platform.
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An Organotellurium Compound with antioxidant activity against excitotoxic agents without neurotoxic effects in brain of rats.
Brain research bulletin, 2008Co-Authors: Daiana Silva Ávila, Priscila Gubert, Aline Palma, Dirleise Colle, Diego Alves, Cristina Wayne Nogueira, João Batista Teixeira Rocha, Félix Alexandre Antunes SoaresAbstract:The glutamatergic system is an important target in many neurodegenerative diseases and for several neurotoxic drugs. Organotellurium Compounds are often very good free radical scavengers' agents. Recently, we reported that diethyl-2-phenyl-2-tellurophenyl vinylphosphonate is a Compound with low toxicity in vitro and in vivo, as well as also possesses antioxidant activity against iron-induced lipid peroxidation. The aim of this study was to evaluate in vitro the antioxidant and mitochondrial protective effect of this Organotellurium Compound against quinolinic acid (QA) and sodium nitroprusside (SNP), and to evaluate the in vitro actions of this Organotellurium Compound in the glutamatergic system in brain of rats. We observed that the telluro vinylphosphonate possess an antioxidant activity against QA and SNP at micromolar concentrations. When tested at antioxidant concentrations (from 2 to 10muM), the Compound does not affect the mitochondrial viability and [3H]glutamate uptake in slices from cerebral cortex, hippocampus and striatum, [3H]glutamate release from synaptosomal preparations and [3H]glutamate binding in membrane preparation. Our data suggest that the telluro vinylphosphonate act as an antioxidant in the central nervous system in vitro with no effects on the glutamatergic system; nevertheless more studies in different models of brain injury must be performed in order to corroborate our findings.
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A biochemical and toxicological study with diethyl 2-phenyl-2-tellurophenyl vinylphosphonate in a sub-chronic intraperitoneal treatment in mice.
Life sciences, 2007Co-Authors: Daiana Silva Ávila, Cristina W. Nogueira, João Rocha, Priscila Gubert, Diego Alves, Cristiane L. Dalla Corte, Félix Alexandre Antunes SoaresAbstract:Diethyl-2-phenyl-2-tellurophenyl vinylphosphonate (DPTVP) is an Organotellurium Compound with low toxicity after subcutaneous administration in mice. This study evaluated possible in vivo and ex vivo toxicological effects of daily injections of DPTVP for 12 days in mice, using the intraperitoneal administration. This route potentially increases the pharmacokinetics of absorption, distribution, metabolism and toxicity of DPTVP. Treatment with DPTVP (0, 30, 50, 75, 100, 250, 350 or 500 micromol/kg) were not associated with mortality or body weight loss. Nevertheless, the liver and liver-to-body weight ratio increased in groups treated with 350 and 500 micromol/kg of DPTVP. However, plasmatic aspartate and alanine aminotransferase activities (classical markers of hepatotoxicity) were not increased after diethyl-2-phenyl-2-tellurophenyl vinylphosphonate administration. Hepatic, renal and cerebral thiobarbituric acid reactive substances (TBARS), delta-ALA-D activity and Vitamin C levels were not modified after DPTVP treatment. Renal and hepatic superoxide dismutase (SOD) and catalase (CAT) were unchanged after DPTVP treatment. Conversely, SOD activity significantly increased in brain in groups treated with 50, 75, 100 and 500 micromol/kg of DPTVP treated groups. Our findings corroborates that brain is a potential target for organochalcogen action. The absence of severe overt signs of toxicity after sub-chronic exposure to DPTVP reinforces the necessity for more detailed pharmacological studies concerning this new Organotellurium Compound.
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Diethyl 2-phenyl-2 tellurophenyl vinylphosphonate: an Organotellurium Compound with low toxicity.
Toxicology, 2006Co-Authors: Daiana Silva Ávila, Marisa C. Beque, Vanderlei Folmer, Antonio L. Braga, Gilson Zeni, Cristina W. Nogueira, Félix Alexandre Antunes Soares, João RochaAbstract:It is well-known that Organotellurium Compounds can have antioxidant activity in vitro, but in vivo these Compounds can be potentially toxic to rodents. Here we investigated the potential in vitro and ex vivo toxicity of a new beta-organochalcogenyl vinylphosphonate, the diethyl 2-phenyl-2 tellurophenyl vinylphosphonate. The in vitro antioxidant activity of this Organotellurium Compound was also investigated. In vitro, the rate of dithiotreitol (DTT) oxidation was increased and the activity of cerebral, renal and hepatic delta-aminolevulinate dehydratase (delta-ALA-D) was decreased by diethyl 2-phenyl-2-tellurophenyl vinylphosphonate (120-1200 microM), indicating that this Compound oxidize-SH groups. The antioxidant activity was also observed in brain, liver and kidney, in very low concentrations (0.4, 1.0, 4.0, 10.0 and 40.0 microM), and this capacity was comparable to the antioxidant standard Organotellurium Compound, diphenyl ditelluride. In vivo, delta-ALA-D activity in liver, kidney and brain of mice treated for 12 days with dimethylsulfoxide (DMSO) as vehicle, 25, 75 or 250 micromol/kg of diethyl 2-phenyl-2-tellurophenyl vinylphosphonate was not affected. Furthermore, only one animal treated with the highest dose died, whereas all animals treated with diphenyl ditteluride died in the fourth day. These results suggest that this novel Organotellurium Compound interacts with the sulfhydryl groups, however only at higher doses when compared with diphenyl ditelluride. Since diethyl 2-phenyl-2 tellurophenyl vinylphosphonate had low toxicity to mice after sub-chronic exposure, it becomes important to investigate its possible pharmacological properties.
João Rocha - One of the best experts on this subject based on the ideXlab platform.
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A biochemical and toxicological study with diethyl 2-phenyl-2-tellurophenyl vinylphosphonate in a sub-chronic intraperitoneal treatment in mice.
Life sciences, 2007Co-Authors: Daiana Silva Ávila, Cristina W. Nogueira, João Rocha, Priscila Gubert, Diego Alves, Cristiane L. Dalla Corte, Félix Alexandre Antunes SoaresAbstract:Diethyl-2-phenyl-2-tellurophenyl vinylphosphonate (DPTVP) is an Organotellurium Compound with low toxicity after subcutaneous administration in mice. This study evaluated possible in vivo and ex vivo toxicological effects of daily injections of DPTVP for 12 days in mice, using the intraperitoneal administration. This route potentially increases the pharmacokinetics of absorption, distribution, metabolism and toxicity of DPTVP. Treatment with DPTVP (0, 30, 50, 75, 100, 250, 350 or 500 micromol/kg) were not associated with mortality or body weight loss. Nevertheless, the liver and liver-to-body weight ratio increased in groups treated with 350 and 500 micromol/kg of DPTVP. However, plasmatic aspartate and alanine aminotransferase activities (classical markers of hepatotoxicity) were not increased after diethyl-2-phenyl-2-tellurophenyl vinylphosphonate administration. Hepatic, renal and cerebral thiobarbituric acid reactive substances (TBARS), delta-ALA-D activity and Vitamin C levels were not modified after DPTVP treatment. Renal and hepatic superoxide dismutase (SOD) and catalase (CAT) were unchanged after DPTVP treatment. Conversely, SOD activity significantly increased in brain in groups treated with 50, 75, 100 and 500 micromol/kg of DPTVP treated groups. Our findings corroborates that brain is a potential target for organochalcogen action. The absence of severe overt signs of toxicity after sub-chronic exposure to DPTVP reinforces the necessity for more detailed pharmacological studies concerning this new Organotellurium Compound.
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Diethyl 2-phenyl-2 tellurophenyl vinylphosphonate: an Organotellurium Compound with low toxicity.
Toxicology, 2006Co-Authors: Daiana Silva Ávila, Marisa C. Beque, Vanderlei Folmer, Antonio L. Braga, Gilson Zeni, Cristina W. Nogueira, Félix Alexandre Antunes Soares, João RochaAbstract:It is well-known that Organotellurium Compounds can have antioxidant activity in vitro, but in vivo these Compounds can be potentially toxic to rodents. Here we investigated the potential in vitro and ex vivo toxicity of a new beta-organochalcogenyl vinylphosphonate, the diethyl 2-phenyl-2 tellurophenyl vinylphosphonate. The in vitro antioxidant activity of this Organotellurium Compound was also investigated. In vitro, the rate of dithiotreitol (DTT) oxidation was increased and the activity of cerebral, renal and hepatic delta-aminolevulinate dehydratase (delta-ALA-D) was decreased by diethyl 2-phenyl-2-tellurophenyl vinylphosphonate (120-1200 microM), indicating that this Compound oxidize-SH groups. The antioxidant activity was also observed in brain, liver and kidney, in very low concentrations (0.4, 1.0, 4.0, 10.0 and 40.0 microM), and this capacity was comparable to the antioxidant standard Organotellurium Compound, diphenyl ditelluride. In vivo, delta-ALA-D activity in liver, kidney and brain of mice treated for 12 days with dimethylsulfoxide (DMSO) as vehicle, 25, 75 or 250 micromol/kg of diethyl 2-phenyl-2-tellurophenyl vinylphosphonate was not affected. Furthermore, only one animal treated with the highest dose died, whereas all animals treated with diphenyl ditteluride died in the fourth day. These results suggest that this novel Organotellurium Compound interacts with the sulfhydryl groups, however only at higher doses when compared with diphenyl ditelluride. Since diethyl 2-phenyl-2 tellurophenyl vinylphosphonate had low toxicity to mice after sub-chronic exposure, it becomes important to investigate its possible pharmacological properties.
Michael Albeck - One of the best experts on this subject based on the ideXlab platform.
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The Organotellurium Compound ammonium trichloro(dioxoethylene-o,o')tellurate reacts with homocysteine to form homocystine and decreases homocysteine levels in hyperhomocysteinemic mice.
The FEBS journal, 2007Co-Authors: Eitan Okun, Yahav Dikshtein, Alon Carmely, Hagar Saida, Gabi M. Frei, Ben-ami Sela, Lydia Varshavsky, Asher Ofir, Esthy Levy, Michael AlbeckAbstract:Ammonium trichloro(dioxoethylene-o,o′)tellurate (AS101) is an Organotellurium Compound with pleiotropic functions that has been associated with antitumoral, immunomodulatory and antineurodegenerative activities. Tellurium Compounds with a +4 oxidation state, such as AS101, react uniquely with thiols, forming disulfide molecules. In light of this, we tested whether AS101 can react with the amino acid homocysteine both in vitro and in vivo. AS101 conferred protection against homocysteine-induced apoptosis of HL-60 cells. The protective mechanism of AS101 against homocysteine toxicity was directly mediated by its chemical reactivity, whereby AS101 reacted with homocysteine to form homocystine, the less toxic disulfide form of homocysteine. Moreover, AS101 was shown here to reduce the levels of total homocysteine in an in vivo model of hyperhomocysteinemia. As a result, AS101 also prevented sperm cells from undergoing homocysteine-induced DNA fragmentation. Taken together, our results suggest that the Organotellurium Compound AS101 may be of clinical value in reducing total circulatory homocysteine levels.
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The Organotellurium Compound ammonium trichloro(dioxoethylene-0,0') tellurate enhances neuronal survival and improves functional outcome in an ischemic stroke model in mice.
Journal of neurochemistry, 2007Co-Authors: Eitan Okun, Benjamin Sredni, Michael Albeck, Thiruma V. Arumugam, Sung-chun Tang, Marc Gleichmann, Mark P. MattsonAbstract:Ammonium trichloro(dioxoethylene-0,0′) tellurate (AS101) is a non-toxic Organotellurium Compound with pleiotropic activities. It was recently shown to induce production of the neurotrophic factor glial cell line-derived neurotrophic factor and to rescue neuronal-like PC-12 cells from neurotrophic factor deprivation-induced apoptosis. In this study, we show that AS101 improves functional outcome and reduces brain damage in a mouse model of focal ischemic stroke. Both pre-stroke and post-stroke intraperitoneal treatments with AS101 reduced infarct size and edema and improved the neurological function of the animals. AS101 treatments reduced both apoptotic and inflammatory caspase activities, and also inhibited protein tyrosine nitration suggesting that AS101 suppresses oxidative stress. Studies of cultured neurons showed that AS101 confers protection against apoptosis induced by either glucose deprivation or the lipid peroxidation product 4-hydroxynonenal. Moreover, AS101 treatment reduced glutamate-induced intracellular calcium elevation, a major contributor to neuronal death in stroke. As AS101 has an excellent safety profile in humans, our pre-clinical data suggest a potential therapeutic benefit of AS101 in patients suffering from stroke and other neurodegenerative conditions.
Cristina W. Nogueira - One of the best experts on this subject based on the ideXlab platform.
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A biochemical and toxicological study with diethyl 2-phenyl-2-tellurophenyl vinylphosphonate in a sub-chronic intraperitoneal treatment in mice.
Life sciences, 2007Co-Authors: Daiana Silva Ávila, Cristina W. Nogueira, João Rocha, Priscila Gubert, Diego Alves, Cristiane L. Dalla Corte, Félix Alexandre Antunes SoaresAbstract:Diethyl-2-phenyl-2-tellurophenyl vinylphosphonate (DPTVP) is an Organotellurium Compound with low toxicity after subcutaneous administration in mice. This study evaluated possible in vivo and ex vivo toxicological effects of daily injections of DPTVP for 12 days in mice, using the intraperitoneal administration. This route potentially increases the pharmacokinetics of absorption, distribution, metabolism and toxicity of DPTVP. Treatment with DPTVP (0, 30, 50, 75, 100, 250, 350 or 500 micromol/kg) were not associated with mortality or body weight loss. Nevertheless, the liver and liver-to-body weight ratio increased in groups treated with 350 and 500 micromol/kg of DPTVP. However, plasmatic aspartate and alanine aminotransferase activities (classical markers of hepatotoxicity) were not increased after diethyl-2-phenyl-2-tellurophenyl vinylphosphonate administration. Hepatic, renal and cerebral thiobarbituric acid reactive substances (TBARS), delta-ALA-D activity and Vitamin C levels were not modified after DPTVP treatment. Renal and hepatic superoxide dismutase (SOD) and catalase (CAT) were unchanged after DPTVP treatment. Conversely, SOD activity significantly increased in brain in groups treated with 50, 75, 100 and 500 micromol/kg of DPTVP treated groups. Our findings corroborates that brain is a potential target for organochalcogen action. The absence of severe overt signs of toxicity after sub-chronic exposure to DPTVP reinforces the necessity for more detailed pharmacological studies concerning this new Organotellurium Compound.
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Diethyl 2-phenyl-2 tellurophenyl vinylphosphonate: an Organotellurium Compound with low toxicity.
Toxicology, 2006Co-Authors: Daiana Silva Ávila, Marisa C. Beque, Vanderlei Folmer, Antonio L. Braga, Gilson Zeni, Cristina W. Nogueira, Félix Alexandre Antunes Soares, João RochaAbstract:It is well-known that Organotellurium Compounds can have antioxidant activity in vitro, but in vivo these Compounds can be potentially toxic to rodents. Here we investigated the potential in vitro and ex vivo toxicity of a new beta-organochalcogenyl vinylphosphonate, the diethyl 2-phenyl-2 tellurophenyl vinylphosphonate. The in vitro antioxidant activity of this Organotellurium Compound was also investigated. In vitro, the rate of dithiotreitol (DTT) oxidation was increased and the activity of cerebral, renal and hepatic delta-aminolevulinate dehydratase (delta-ALA-D) was decreased by diethyl 2-phenyl-2-tellurophenyl vinylphosphonate (120-1200 microM), indicating that this Compound oxidize-SH groups. The antioxidant activity was also observed in brain, liver and kidney, in very low concentrations (0.4, 1.0, 4.0, 10.0 and 40.0 microM), and this capacity was comparable to the antioxidant standard Organotellurium Compound, diphenyl ditelluride. In vivo, delta-ALA-D activity in liver, kidney and brain of mice treated for 12 days with dimethylsulfoxide (DMSO) as vehicle, 25, 75 or 250 micromol/kg of diethyl 2-phenyl-2-tellurophenyl vinylphosphonate was not affected. Furthermore, only one animal treated with the highest dose died, whereas all animals treated with diphenyl ditteluride died in the fourth day. These results suggest that this novel Organotellurium Compound interacts with the sulfhydryl groups, however only at higher doses when compared with diphenyl ditelluride. Since diethyl 2-phenyl-2 tellurophenyl vinylphosphonate had low toxicity to mice after sub-chronic exposure, it becomes important to investigate its possible pharmacological properties.