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Hisao Matsui - One of the best experts on this subject based on the ideXlab platform.
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In vitro metabolism of tributyltin and Triphenyltin by human cytochrome P-450 isoforms.
Toxicology, 2006Co-Authors: Shuji Ohhira, Mitsunori Enomoto, Hisao MatsuiAbstract:The metabolic fate of tributyltin and Triphenyltin may contribute to the toxicity of these chemicals. We used human hepatic cytochrome P-450 (CYP) systems to confirm the specific CYP(s) involved in the in vitro metabolism of tributyltin and Triphenyltin. There were no significant sex differences in the metabolic pattern of tributyltin or Triphenyltin, indicating that the CYP(s) responsible for the metabolism of these chemicals in humans is/are not sex-specific form(s). Six major drug-metabolizing isoforms of cDNA-expressed human CYPs and the CYP2C subfamily were tested to determine their metabolic capacities for tributyltin and Triphenyltin. CYP2C9, 2C18, 2C19, and 3A4 significantly mediated both dealkylation and dearylation of these triorganotins. Furthermore, the metabolism of tributyltin and Triphenyltin was significantly inhibited in vitro by pretreatment with selective inhibitors, azamulin for CYP3A4 and N-3-benzylnirvanol for CYP2C19. Since the CYP2C18 content of hepatic microsomes in humans is relatively low, CYP2C9, 2C19, and 3A4 might be the main isoforms of CYP that are responsible for tributyltin and Triphenyltin metabolism in the human liver.
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Identification of principal cytochrome P-450 in Triphenyltin metabolism in rats.
Toxicology letters, 2004Co-Authors: Shuji Ohhira, Masatomo Watanabe, Hisao MatsuiAbstract:The in vivo and in vitro metabolism of Triphenyltin using rat hepatic cytochrome P-450 (CYP) systems was investigated to confirm the specific CYP that is closely related to Triphenyltin metabolism. No significant sex differences occurred between the in vivo and in vitro metabolic patterns of the chemical, indicating that the principal CYP for Triphenyltin metabolism in rats is not a sex-specific form of CYP. In addition, seven types of complementary DNA (cDNA)-expressed rat CYPs, typical phenobarbital (PB)-inducible forms and the CYP2C subfamily were tested to determine the activity of Triphenyltin metabolism. Among the CYP isoforms studied, although CYP2B1 had a small metabolic capacity, a marked dearylation of the chemical was induced by CYP2C6. Furthermore, anti-rat CYP2C6 antibodies and cimetidine, a selective CYP2C6 inhibitor, inhibited Triphenyltin dearylation activity in the hepatic microsomes of rats. Taken together, these findings suggest that CYP2C6 is the principal CYP for the Triphenyltin metabolism in rats.
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Metabolism of tributyltin and Triphenyltin by rat, hamster and human hepatic microsomes
Archives of Toxicology, 2003Co-Authors: Shuji Ohhira, Masatomo Watanabe, Hisao MatsuiAbstract:Tributyltin and Triphenyltin are metabolized by cytochrome P-450 system enzymes, and their metabolic fate may contribute to the toxicity of the chemicals. In the current study, the in vitro metabolism of tributyltin and Triphenyltin by rat, hamster and human hepatic microsomes was investigated to elucidate the metabolic competence for these compounds in humans. The metabolic reaction using microsome-NADPH system that is usually conducted was not applicable to in vitro metabolism of organotins, especially Triphenyltin. We therefore examined the effects of dithiothreitol (DTT), one of the antioxidants for sulfhydryl groups, to determine the in vitro metabolism of tributyltin and Triphenyltin. As a result, the treatment with 0.1 mM DTT in vitro increased the activity of the microsomal monooxygenase system for metabolism of tributyltin as well as Triphenyltin; the total yield of tributyltin and Triphenyltin metabolites as tin increased, respectively, by approximately 1.8 and 8.9 times for rat, 2.1 and 1.2 times for hamster, and 1.6 and 1.5 times for human. It is suggested that the organotins directly inactivate cytochrome P-450 because of the interaction with critical sulfhydryl groups of the hemoprotein. We confirmed the utility of this in vitro metabolic system using DTT in the hepatic microsomes of phenobarbital (PB)-pretreated and untreated hamsters. Thus, the in vitro metabolic system described here was applied to a comparative study of the metabolism of organotins in rats, hamsters and humans. Tributyltin was metabolized more readily than Triphenyltin in all the species. In humans, the in vitro metabolic pattern resembled that of hamsters, which were susceptible to in vivo Triphenyltin toxicity because of incompetent metabolism. It is possible that the hamster is a qualitatively and quantitatively suitable animal model for exploring the influence of tributyltin and Triphenyltin in humans.
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Effects of pretreatment with SKF-525A on Triphenyltin metabolism and toxicity in mice.
Toxicology letters, 2000Co-Authors: Shuji Ohhira, Hisao Matsui, Keita WatanabeAbstract:Abstract The effects of cytochrome P-450 inhibition by α-phenyl-α-propylbenzeneacetic acid 2-[diethylamino]-ethyl ester hydrochloride (SKF-525A), which inhibits the activity of a number of cytochrome P-450s, on Triphenyltin metabolism and toxicity in mice were studied. At 24 h after Triphenyltin administration, the Triphenyltin levels in the tissues of SKF-525A-pretreated mice were about three times of those in the tissues of SKF-525A-untreated mice and the ratio of metabolites to parent Triphenyltin in the tissues of SKF-525A-pretreated mice was lower than those in the tissues of SKF-525A-untreated mice. These data indicate that the pretreatment of SKF-525A decelerated the Triphenyltin metabolism and increased Triphenyltin accumulation in the tissues of mice. Although Triphenyltin did not affect plasma glucose levels of in the SKF-525A-untreated mice, the Triphenyltin produced marked hyperglycemia in SKF-525A-pretreated mice. These results suggest that the inhibition of cytochrome P-450 system enzymes by SKF-525A affects the metabolism and toxicity of Triphenyltin and has a key role in inducing the hyperglycemic action of Triphenyltin, i.e. by increasing Triphenyltin accumulation in the mice.
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Effects of pretreatment with cytochrome P-450 inducers, especially phenobarbital on Triphenyltin metabolism and toxicity in hamsters
Toxicology, 1999Co-Authors: Shuji Ohhira, Hisao Matsui, Keita WatanabeAbstract:The effects of cytochrome P-450 (CYP) induction by phenobarbital (PB), CYP 2B, 2C, and 3A inducer in mammalians, on Triphenyltin metabolism and toxicity in hamsters were studied. A single dose of 50 mg/kg of Triphenyltin chloride was given by gavage to hamsters after pretreatment with or without PB for 3 days continuously at a daily dose of 80 mg/kg intraperitoneally (i.p.). Although the Triphenyltin produced marked but reversible hyperglycemia and hypertriglyceridemia in PB-untreated hamsters, the pretreatment of hamsters with PB, which increased levels of CYP, suppressed the diabetogenic effects compared with PB-untreated hamsters. Furthermore, we investigated whether the mitigation of Triphenyltin-induced diabetogenic toxicity by PB pretreatment is due to an alteration of Triphenyltin metabolism. Triphenyltin and its metabolites in liver, kidneys, pancreas and brain were determined by gas chromatography periodically for 96 h after Triphenyltin administration in both groups of hamsters. The initial Triphenyltin levels in the tissues of PB-pretreated hamsters were about half of those in the tissues of PB-untreated hamsters and PB pretreatment accelerated metabolism of Triphenyltin at early stage in hamsters. We also examined the other CYP 1A and 2A inducers, beta-naphthoflavone (B-NF) and 3-methylcholanthrene (MC). The PB pretreatment showed the strongest suppression of the toxicity at 24 h after the Triphenyltin intubation, compared with the effects of B-NF and MC. In addition, the maximum proportion of diphenyltin to parent Triphenyltin in pancreas was observed in PB-treated hamsters. These findings suggest that the induction of CYP system enzymes affects the metabolism and toxicity of Triphenyltin in hamsters. Especially, based on effects of PB and other CYP inducers, PB induction has a key role in suppressing the diabetogenic action of Triphenyltin, i.e. by decreasing Triphenyltin accumulation in the hamsters.
V. G. Kumar Das - One of the best experts on this subject based on the ideXlab platform.
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Speciation of phenyltin(IV) compounds using high‐performance liquid chromatography: Part 1. The direct analysis of mixed standard solutions of tetraphenyltin, Triphenyltin chloride, Triphenyltin hydroxide and Triphenyltin acetate
Applied Organometallic Chemistry, 2002Co-Authors: Shobha K. Lal, G. H. Tan, N. H. Tioh, V. G. Kumar DasAbstract:A rapid speciation high-performance liquid chromatography (HPLC) method has been developed for the simultaneous determination of phenyltin compounds. The commercially important products of Triphenyltin-chloride, -acetate, -hydroxide and tetraphenyltin were separated by reversed-phase HPLC on a Waters Spherisorb S5W ODS-2 (octadecylsilica) column using an isocratic mixture of 90:10 (v/v) acetonitrile:water as the mobile phase at a flow rate of 1 ml min−1. The phenyltin compounds were detected by UV detection at 254 nm and the total elution time is 8 min. The elution order is Triphenyltin-chloride, -acetate, -hydroxide and tetraphenyltin. Detection limits were 0.01 ppm for each of the Triphenyltin compounds and 0.02 ppm for tetraphenyltin. Spiked water samples containing the three biocidal Triphenyltin compounds could also be analysed simultaneously by the above method without the need for any prior derivatization, following extraction with toluene. The versatility of the method in sensing substituent group variations on the phenyl ring was also demonstrated by the successful resolution of the hydroxides, tris(p-chlorophenyl)tin hydroxide, diphenyl(p-chlorophenyl)tin hydroxide and Triphenyltin hydroxide. Copyright © 2002 John Wiley & Sons, Ltd.
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Speciation of phenyltin(IV) compounds using high-performance liquid chromatography. Part 2: The direct analysis of mixed standard solutions of Triphenyltin halides/pseudohalide and of Triphenyltin carboxylates containing functional group variations i
Applied Organometallic Chemistry, 2002Co-Authors: Shobha K. Lal, G. H. Tan, N. H. Tioh, V. G. Kumar DasAbstract:Simultaneous speciation of mixed standard solutions of Triphenyltin halides (Triphenyltin chloride, bromide, iodide) and pseudohalide (Triphenyltin isothiocyanate) has been achieved with reversed-phase high-performance liquid chromatography on a Waters Spherisorb S5W ODS-2 (octadecyl-silica) column. An isocratic mixture of 95:5 (v/v) acetonitrile:water was used as the mobile phase at a flow rate of 1 ml min−1. A series of selected Triphenyltin carboxylates, Ph3SnOCOZ, where Z = Me, Ph, CH:CHPh, CH:NOMe, CH2SC5H4N and CH2SC(S)NMe2, was also similarly analysed using this system with two separate isocratic elutions using 100% acetonitrile and 96:4 (v/v) acetonitrile:water as the mobile phase. UV detection was done at 254 nm and the total run time for each analysis was less than 3 min. The detection limits for all the phenyltin(IV) compounds were in the range 0.01–0.03 ppm. Spiked water samples containing the Triphenyltin carboxylates could also be simultaneously analysed by the above method without the need for any prior derivatization, following extraction with hexane. Pretreatment of the aqueous sample with NaCl/HCl and of the organic phase with hexamethylphosphoramide enabled recoveries of about 80% of the Triphenyltins. Copyright © 2002 John Wiley & Sons, Ltd.
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Triphenyltin N,N-dimethylthiocarbamoylacetate, Triphenyltin N,N-pentamethylenecarbamoylthioacetate and cyclopentyldiphenyltin N,N-dimethylthiocarbamoylacetate
Acta Crystallographica Section C Crystal Structure Communications, 1999Co-Authors: V. G. Kumar DasAbstract:Carboxylate bridges link two independent molecules of Triphenyltin N,N-dimethylthiocarbamoylacetate, [Sn(C 6 H 5 ) 3 (C 5 H 8 NO 3 S)], into a helical chain {i.e. catenapoly[Triphenyltin-μ-(N,N-dimethylthiocarbamoylacetato-O:O')]}, as do the carboxylate bridges in Triphenyltin N,N-pentamethylenecarbamoylthioacetate, [Sn(C 6 H 5 ) 3 (C 8 H 12 NO 3 S)] {i.e. catena-poly[Triphenyltin-μ-(N,N-pentamethylenethiocarbamoylacetato-O:O')]}, and cyclopentyldiphenyltin N,N-dimethylthiocarbamoylacetate, [Sn(C 6 H 5 ) 2 (C 5 H 9 )(C 5 H 8 NO 3 S)] {i.e. catena-poly[cyclopentyldiphenyltin-μ-(N,N-dimethylthiocarbamoylacetato-O:O']}.
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catena‐Poly[Triphenyltin‐μ‐(N,N‐diethylthiocarbamoylthioacetato‐O:O')], catena‐poly[Triphenyltin‐μ‐(N‐methyl‐N‐phenylthiocarbamoylthioacetato‐O:O')] and triphenyl(N,N‐tetramethylenethiocarbamoylthioacetato‐O)tin
Acta Crystallographica Section C Crystal Structure Communications, 1999Co-Authors: V. G. Kumar Das, James M. HookAbstract:Carboxylate bridges link the two independent molecules of Triphenyltin N, N-diethylthiocarbamoylthioacetate, (I), and the four independent molecules of Triphenyltin N-methyl-N-phenylthiocarbamoylthioacetate, (II), into linear chains whose Sn atoms show trans-trigonal-bipyramidal coordination, i.e. (I) is catena-poly[Triphenyltin-μ-(N,N-diethylthiocarbamoylthioacetato-O:O')], [Sn(C 6 H 5 ) 3 (μ-C 7 H 12 NO 2 S 2 )] n , and (II) is catena-poly[Triphenyltin-μ-(N-methyl-N-phenylthiocarbamoylthioacetato-O:O')], [Sn(C 6 H 5 ) 3 (μ-C 10 H 10 NO 2 S 2 )] n . Triphenyltin N,N-tetramethylenethiocarbamoylthioacetate {or triphenyl (N,N-tetramethylenethiocarbamoylthioacetato-O)tin, [Sn(C 6 H 5 ) 3 (C 7 H 10 -NO 2 S 2 )]} exists as a monomeric tetrahedral molecule.
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[3-(Diethylphosphono)propionato]Triphenyltin
Acta Crystallographica Section C Crystal Structure Communications, 1996Co-Authors: V. G. Kumar DasAbstract:In the title compound, [Sn(C7H14O5P)(C6H5)3], the planar Triphenyltin cations are axially bridged through the carboxyl and phosphoryl O atoms of the 3-(diethylphosphono)propionate anions into zigzag chains that run parallel to the c axis {i.e. catena-poly[Triphenyltin-μ-3(diethylphosphono)propionato-O:OP = O]}.
George Eng - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and structural determination of ionic Triphenyltin complexes of mercaptoacetic and 3-mercaptopropionic acids
Journal of Coordination Chemistry, 2020Co-Authors: Raymond Devaughn, George Eng, Robert D. Pike, Xueqing SongAbstract:Two ionic Triphenyltin complexes were obtained when two thiocarboxylic acids, mercaptoacetic acid and 3-mercaptopropionic acid, were mixed with Triphenyltin hydroxide in the presence of dicylcohexy...
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Synthesis and crystal structures of ionic Triphenyltin complexes with oxalic and malonic acid
Journal of Coordination Chemistry, 2013Co-Authors: Dain Thorpe, George Eng, Robert D. Pike, Andrei Callejas, Dmitry E. Royzman, Xueqing SongAbstract:Two ionic Triphenyltin complexes (1 and 2) were obtained via condensation of Triphenyltin hydroxide with oxalic and malonic acids in the presence of di-isobutylamine. Their structures have been characterized by IR and multinuclear (1H, 13C, and 119Sn) NMR spectroscopies. The coordinations of tin in the two Triphenyltin complexes are confirmed by X-ray crystallographic studies. In the solid state, oxalate complex 1 consists of a di-isobutylammonium cation and an oxalatotriphenylstannate anion. Tin is five-coordinate with a cis-trigonal-bipyramid (TBP) geometry, as the oxalate is a chelating bidentate ligand. Complex 1 is a 1-D polymer via hydrogen bonding between carboxylate oxygen and ammonium nitrogen. The crystallographic studies reveal that 2 is a trinuclear Triphenyltin complex formed with the molar ratio of tin, acid, and amine being 3 : 2 : 1. A negative charge is delocalized among the three tins in the complex; all tins have trans-TBP geometry with three phenyls in the equatorial plane and two O in...
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Synthesis and structural determination of two Triphenyltin thiosalicylates
Journal of Coordination Chemistry, 2009Co-Authors: Russell Knighton, Xueqing Song, Robert D. Pike, Angel C. De Dios, Leah B. Casabianca, George EngAbstract:Two structurally different Triphenyltin complexes of thiosalicylic acid were obtained depending on the amine used. Bis(Triphenyltin) thiosalicylate was obtained when diethylamine was used while dicyclohexylammonium thiosalicylatotriphenylstannate resulted with dicyclohexylamine. Their structures have been characterized by IR and multi-nuclear (1H, 13C, 119Sn) NMR spectroscopies. In the solid state, both tins in the bis(Triphenyltin) thiosalicylate complex are four-coordinate while the tin in dicyclohexylammonium thiosalicylatetriphenylstannate is five-coordinate. However, in solution, dissociation occurs in the dicyclohexylammonium thiosalicylatotriphenylstannate complex reducing the coordination of tin to four. The coordination of the tin atoms in the two Triphenyltin complexes is confirmed by X-ray crystallographic studies.
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The effects of salinity and pH on the speciation of some Triphenyltin compounds in estuarine sediments using Mössbauer spectroscopy
Applied Organometallic Chemistry, 1993Co-Authors: Deborah Whalen, Rosemarie A. Lucero, Leopold May, George EngAbstract:The speciation of some Triphenyltin compounds i.e. Triphenyltin hydroxide, Triphenyltin chloride, Triphenyltin fluoride, under varying salinity and pH conditions, was studied by Mossbauer spectroscopy in both anoxic and oxic estuarine sediments. The results indicate that altering the pH or salinity of the sediment environment does not apparently affect the speciation of these compounds.
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Speciation of some Triphenyltin compounds in estuarine sediments using mössbauer spectroscopy
Applied Organometallic Chemistry, 1992Co-Authors: Rosemarie A. Lucero, Monicah A. Otieno, Leopold May, George EngAbstract:The speciation of several Triphenyltin compounds, i.e. Triphenyltin hydroxide, acetate, chloride and fluoride, was studied by Mossbauer spectroscopy in both anaerobic and aerobic estuarine sediments. The results indicated that Triphenyltin hydroxide and acetate were converted to the Triphenyltin cation, the species that interacts with the sediments. However, both Triphenyltin fluoride and chloride remained in their molecular form in their interaction with the sediments.
Shuji Ohhira - One of the best experts on this subject based on the ideXlab platform.
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In vitro metabolism of tributyltin and Triphenyltin by human cytochrome P-450 isoforms.
Toxicology, 2006Co-Authors: Shuji Ohhira, Mitsunori Enomoto, Hisao MatsuiAbstract:The metabolic fate of tributyltin and Triphenyltin may contribute to the toxicity of these chemicals. We used human hepatic cytochrome P-450 (CYP) systems to confirm the specific CYP(s) involved in the in vitro metabolism of tributyltin and Triphenyltin. There were no significant sex differences in the metabolic pattern of tributyltin or Triphenyltin, indicating that the CYP(s) responsible for the metabolism of these chemicals in humans is/are not sex-specific form(s). Six major drug-metabolizing isoforms of cDNA-expressed human CYPs and the CYP2C subfamily were tested to determine their metabolic capacities for tributyltin and Triphenyltin. CYP2C9, 2C18, 2C19, and 3A4 significantly mediated both dealkylation and dearylation of these triorganotins. Furthermore, the metabolism of tributyltin and Triphenyltin was significantly inhibited in vitro by pretreatment with selective inhibitors, azamulin for CYP3A4 and N-3-benzylnirvanol for CYP2C19. Since the CYP2C18 content of hepatic microsomes in humans is relatively low, CYP2C9, 2C19, and 3A4 might be the main isoforms of CYP that are responsible for tributyltin and Triphenyltin metabolism in the human liver.
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Identification of principal cytochrome P-450 in Triphenyltin metabolism in rats.
Toxicology letters, 2004Co-Authors: Shuji Ohhira, Masatomo Watanabe, Hisao MatsuiAbstract:The in vivo and in vitro metabolism of Triphenyltin using rat hepatic cytochrome P-450 (CYP) systems was investigated to confirm the specific CYP that is closely related to Triphenyltin metabolism. No significant sex differences occurred between the in vivo and in vitro metabolic patterns of the chemical, indicating that the principal CYP for Triphenyltin metabolism in rats is not a sex-specific form of CYP. In addition, seven types of complementary DNA (cDNA)-expressed rat CYPs, typical phenobarbital (PB)-inducible forms and the CYP2C subfamily were tested to determine the activity of Triphenyltin metabolism. Among the CYP isoforms studied, although CYP2B1 had a small metabolic capacity, a marked dearylation of the chemical was induced by CYP2C6. Furthermore, anti-rat CYP2C6 antibodies and cimetidine, a selective CYP2C6 inhibitor, inhibited Triphenyltin dearylation activity in the hepatic microsomes of rats. Taken together, these findings suggest that CYP2C6 is the principal CYP for the Triphenyltin metabolism in rats.
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Metabolism of tributyltin and Triphenyltin by rat, hamster and human hepatic microsomes
Archives of Toxicology, 2003Co-Authors: Shuji Ohhira, Masatomo Watanabe, Hisao MatsuiAbstract:Tributyltin and Triphenyltin are metabolized by cytochrome P-450 system enzymes, and their metabolic fate may contribute to the toxicity of the chemicals. In the current study, the in vitro metabolism of tributyltin and Triphenyltin by rat, hamster and human hepatic microsomes was investigated to elucidate the metabolic competence for these compounds in humans. The metabolic reaction using microsome-NADPH system that is usually conducted was not applicable to in vitro metabolism of organotins, especially Triphenyltin. We therefore examined the effects of dithiothreitol (DTT), one of the antioxidants for sulfhydryl groups, to determine the in vitro metabolism of tributyltin and Triphenyltin. As a result, the treatment with 0.1 mM DTT in vitro increased the activity of the microsomal monooxygenase system for metabolism of tributyltin as well as Triphenyltin; the total yield of tributyltin and Triphenyltin metabolites as tin increased, respectively, by approximately 1.8 and 8.9 times for rat, 2.1 and 1.2 times for hamster, and 1.6 and 1.5 times for human. It is suggested that the organotins directly inactivate cytochrome P-450 because of the interaction with critical sulfhydryl groups of the hemoprotein. We confirmed the utility of this in vitro metabolic system using DTT in the hepatic microsomes of phenobarbital (PB)-pretreated and untreated hamsters. Thus, the in vitro metabolic system described here was applied to a comparative study of the metabolism of organotins in rats, hamsters and humans. Tributyltin was metabolized more readily than Triphenyltin in all the species. In humans, the in vitro metabolic pattern resembled that of hamsters, which were susceptible to in vivo Triphenyltin toxicity because of incompetent metabolism. It is possible that the hamster is a qualitatively and quantitatively suitable animal model for exploring the influence of tributyltin and Triphenyltin in humans.
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Effects of pretreatment with SKF-525A on Triphenyltin metabolism and toxicity in mice.
Toxicology letters, 2000Co-Authors: Shuji Ohhira, Hisao Matsui, Keita WatanabeAbstract:Abstract The effects of cytochrome P-450 inhibition by α-phenyl-α-propylbenzeneacetic acid 2-[diethylamino]-ethyl ester hydrochloride (SKF-525A), which inhibits the activity of a number of cytochrome P-450s, on Triphenyltin metabolism and toxicity in mice were studied. At 24 h after Triphenyltin administration, the Triphenyltin levels in the tissues of SKF-525A-pretreated mice were about three times of those in the tissues of SKF-525A-untreated mice and the ratio of metabolites to parent Triphenyltin in the tissues of SKF-525A-pretreated mice was lower than those in the tissues of SKF-525A-untreated mice. These data indicate that the pretreatment of SKF-525A decelerated the Triphenyltin metabolism and increased Triphenyltin accumulation in the tissues of mice. Although Triphenyltin did not affect plasma glucose levels of in the SKF-525A-untreated mice, the Triphenyltin produced marked hyperglycemia in SKF-525A-pretreated mice. These results suggest that the inhibition of cytochrome P-450 system enzymes by SKF-525A affects the metabolism and toxicity of Triphenyltin and has a key role in inducing the hyperglycemic action of Triphenyltin, i.e. by increasing Triphenyltin accumulation in the mice.
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Effects of pretreatment with cytochrome P-450 inducers, especially phenobarbital on Triphenyltin metabolism and toxicity in hamsters
Toxicology, 1999Co-Authors: Shuji Ohhira, Hisao Matsui, Keita WatanabeAbstract:The effects of cytochrome P-450 (CYP) induction by phenobarbital (PB), CYP 2B, 2C, and 3A inducer in mammalians, on Triphenyltin metabolism and toxicity in hamsters were studied. A single dose of 50 mg/kg of Triphenyltin chloride was given by gavage to hamsters after pretreatment with or without PB for 3 days continuously at a daily dose of 80 mg/kg intraperitoneally (i.p.). Although the Triphenyltin produced marked but reversible hyperglycemia and hypertriglyceridemia in PB-untreated hamsters, the pretreatment of hamsters with PB, which increased levels of CYP, suppressed the diabetogenic effects compared with PB-untreated hamsters. Furthermore, we investigated whether the mitigation of Triphenyltin-induced diabetogenic toxicity by PB pretreatment is due to an alteration of Triphenyltin metabolism. Triphenyltin and its metabolites in liver, kidneys, pancreas and brain were determined by gas chromatography periodically for 96 h after Triphenyltin administration in both groups of hamsters. The initial Triphenyltin levels in the tissues of PB-pretreated hamsters were about half of those in the tissues of PB-untreated hamsters and PB pretreatment accelerated metabolism of Triphenyltin at early stage in hamsters. We also examined the other CYP 1A and 2A inducers, beta-naphthoflavone (B-NF) and 3-methylcholanthrene (MC). The PB pretreatment showed the strongest suppression of the toxicity at 24 h after the Triphenyltin intubation, compared with the effects of B-NF and MC. In addition, the maximum proportion of diphenyltin to parent Triphenyltin in pancreas was observed in PB-treated hamsters. These findings suggest that the induction of CYP system enzymes affects the metabolism and toxicity of Triphenyltin in hamsters. Especially, based on effects of PB and other CYP inducers, PB induction has a key role in suppressing the diabetogenic action of Triphenyltin, i.e. by decreasing Triphenyltin accumulation in the hamsters.
Shobha K. Lal - One of the best experts on this subject based on the ideXlab platform.
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speciation of phenyltin iv compounds using high performance liquid chromatography part 1 the direct analysis of mixed standard solutions of tetraphenyltin Triphenyltin chloride Triphenyltin hydroxide and Triphenyltin acetate
Applied Organometallic Chemistry, 2002Co-Authors: Shobha K. Lal, G. H. Tan, N. H. Tioh, V. Kumar G. DasAbstract:A rapid speciation high-performance liquid chromatography (HPLC) method has been developed for the simultaneous determination of phenyltin compounds. The commercially important products of Triphenyltin-chloride, -acetate, -hydroxide and tetraphenyltin were separated by reversed-phase HPLC on a Waters Spherisorb S5W ODS-2 (octadecylsilica) column using an isocratic mixture of 90:10 (v/v) acetonitrile:water as the mobile phase at a flow rate of 1 ml min−1. The phenyltin compounds were detected by UV detection at 254 nm and the total elution time is 8 min. The elution order is Triphenyltin-chloride, -acetate, -hydroxide and tetraphenyltin. Detection limits were 0.01 ppm for each of the Triphenyltin compounds and 0.02 ppm for tetraphenyltin. Spiked water samples containing the three biocidal Triphenyltin compounds could also be analysed simultaneously by the above method without the need for any prior derivatization, following extraction with toluene. The versatility of the method in sensing substituent group variations on the phenyl ring was also demonstrated by the successful resolution of the hydroxides, tris(p-chlorophenyl)tin hydroxide, diphenyl(p-chlorophenyl)tin hydroxide and Triphenyltin hydroxide. Copyright © 2002 John Wiley & Sons, Ltd.
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Speciation of phenyltin(IV) compounds using high‐performance liquid chromatography: Part 1. The direct analysis of mixed standard solutions of tetraphenyltin, Triphenyltin chloride, Triphenyltin hydroxide and Triphenyltin acetate
Applied Organometallic Chemistry, 2002Co-Authors: Shobha K. Lal, G. H. Tan, N. H. Tioh, V. G. Kumar DasAbstract:A rapid speciation high-performance liquid chromatography (HPLC) method has been developed for the simultaneous determination of phenyltin compounds. The commercially important products of Triphenyltin-chloride, -acetate, -hydroxide and tetraphenyltin were separated by reversed-phase HPLC on a Waters Spherisorb S5W ODS-2 (octadecylsilica) column using an isocratic mixture of 90:10 (v/v) acetonitrile:water as the mobile phase at a flow rate of 1 ml min−1. The phenyltin compounds were detected by UV detection at 254 nm and the total elution time is 8 min. The elution order is Triphenyltin-chloride, -acetate, -hydroxide and tetraphenyltin. Detection limits were 0.01 ppm for each of the Triphenyltin compounds and 0.02 ppm for tetraphenyltin. Spiked water samples containing the three biocidal Triphenyltin compounds could also be analysed simultaneously by the above method without the need for any prior derivatization, following extraction with toluene. The versatility of the method in sensing substituent group variations on the phenyl ring was also demonstrated by the successful resolution of the hydroxides, tris(p-chlorophenyl)tin hydroxide, diphenyl(p-chlorophenyl)tin hydroxide and Triphenyltin hydroxide. Copyright © 2002 John Wiley & Sons, Ltd.
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Speciation of phenyltin(IV) compounds using high-performance liquid chromatography. Part 2: The direct analysis of mixed standard solutions of Triphenyltin halides/pseudohalide and of Triphenyltin carboxylates containing functional group variations i
Applied Organometallic Chemistry, 2002Co-Authors: Shobha K. Lal, G. H. Tan, N. H. Tioh, V. G. Kumar DasAbstract:Simultaneous speciation of mixed standard solutions of Triphenyltin halides (Triphenyltin chloride, bromide, iodide) and pseudohalide (Triphenyltin isothiocyanate) has been achieved with reversed-phase high-performance liquid chromatography on a Waters Spherisorb S5W ODS-2 (octadecyl-silica) column. An isocratic mixture of 95:5 (v/v) acetonitrile:water was used as the mobile phase at a flow rate of 1 ml min−1. A series of selected Triphenyltin carboxylates, Ph3SnOCOZ, where Z = Me, Ph, CH:CHPh, CH:NOMe, CH2SC5H4N and CH2SC(S)NMe2, was also similarly analysed using this system with two separate isocratic elutions using 100% acetonitrile and 96:4 (v/v) acetonitrile:water as the mobile phase. UV detection was done at 254 nm and the total run time for each analysis was less than 3 min. The detection limits for all the phenyltin(IV) compounds were in the range 0.01–0.03 ppm. Spiked water samples containing the Triphenyltin carboxylates could also be simultaneously analysed by the above method without the need for any prior derivatization, following extraction with hexane. Pretreatment of the aqueous sample with NaCl/HCl and of the organic phase with hexamethylphosphoramide enabled recoveries of about 80% of the Triphenyltins. Copyright © 2002 John Wiley & Sons, Ltd.
