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Desaulniers D, Zhou G, Stalker A, Cummings-Lorbetskie C. Effects of Copper or Zinc Organometallics on Cytotoxicity, DNA Damage and Epigenetic Changes in the HC-04 Human Liver Cell Line. Int J Mol Sci 2023; 24:15580. [PMID: 37958568 PMCID: PMC10650525 DOI: 10.3390/ijms242115580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 10/13/2023] [Accepted: 10/19/2023] [Indexed: 11/15/2023] Open
Abstract
Copper and zinc organometallics have multiple applications and many are considered "data-poor" because the available toxicological information is insufficient for comprehensive health risk assessments. To gain insight into the chemical prioritization and potential structure activity relationship, the current work compares the in vitro toxicity of nine "data-poor" chemicals to five structurally related chemicals and to positive DNA damage inducers (4-nitroquinoline-oxide, aflatoxin-B1). The HC-04 non-cancer human liver cell line was used to investigate the concentration-response effects (24 h and 72 h exposure) on cell proliferation, DNA damage (γH2AX and DNA unwinding assays), and epigenetic effects (global genome changes in DNA methylation and histone modifications using flow cytometry). The 24 h exposure screening data (DNA abundance and damage) suggest a toxicity hierarchy, starting with copper dimethyldithiocarbamate (CDMDC, CAS#137-29-1) > zinc diethyldithiocarbamate (ZDEDC, CAS#14324-55-1) > benzenediazonium, 4-chloro-2-nitro-, and tetrachlorozincate(2-) (2:1) (BDCN4CZ, CAS#14263-89-9); the other chemicals were less toxic and had alternate ranking positions depending on assays. The potency of CDMDC for inducing DNA damage was close to that of the human hepatocarcinogen aflatoxin-B1. Further investigation using sodium-DMDC (SDMDC, CAS#128-04-1), CDMDC and copper demonstrated the role of the interactions between copper and the DMDC organic moiety in generating a high level of CDMDC toxicity. In contrast, additive interactions were not observed with respect to the DNA methylation flow cytometry data in 72 h exposure experiments. They revealed chemical-specific effects, with hypo and hypermethylation induced by copper chloride (CuCl2, CAS#10125-13-0) and zinc-DMDC (ZDMDC, CAS#137-30-4), respectively, but did not show any significant effect of CDMDC or SDMDC. Histone-3 hypoacetylation was a sensitive flow cytometry marker of 24 h exposure to CDMDC. This study can provide insights regarding the prioritization of chemicals for future study, with the aim being to mitigate chemical hazards.
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Affiliation(s)
- Daniel Desaulniers
- Health Canada, Environmental Health Science and Research Bureau, Ottawa, ON K1A 0K9, Canada; (D.D.)
| | - Gu Zhou
- Health Canada, Environmental Health Science and Research Bureau, Ottawa, ON K1A 0K9, Canada; (D.D.)
| | - Andrew Stalker
- Health Canada, Regulatory Research Division, Biologics and Radiopharmaceutical Drugs Directorate, Ottawa, ON K1A 0K9, Canada
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Xie GL, Yu H, Deng MH, Zhao XL, Yu P. A colorimetric microfluidic sensor made by a simple instrumental-free prototyping process for sensitive quantitation of copper. CHEMICAL PAPERS 2019. [DOI: 10.1007/s11696-019-00702-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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3
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Jivan R, Peres J, Damelin LH, Wadee R, Veale RB, Prince S, Mavri-Damelin D. Disulfiram with or without metformin inhibits oesophageal squamous cell carcinoma in vivo. Cancer Lett 2017; 417:1-10. [PMID: 29274360 DOI: 10.1016/j.canlet.2017.12.026] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 11/30/2017] [Accepted: 12/15/2017] [Indexed: 12/18/2022]
Abstract
Oesophageal squamous cell carcinoma (OSCC) is highly prevalent in developing countries but there has been little recent progress into efficacious yet affordable treatment strategies. Drug repurposing is one attractive approach for cancer therapy. Disulfiram (DSF), used to treat alcoholism, inhibits cancer growth and we previously found that DSF perturbs protein degradation/turnover pathways in vitro. This was enhanced by combining DSF with the anti-diabetic drug metformin (Met). Here, we investigated DSF with/without Met, against OSCC in vivo. Nude mice injected subcutaneously with the human OSCC cell line WHCO1, were treated with 30 mg/kg or 50 mg/kg DSF three times per week and with/without Met, for 21 days. DSF and DSF/Met-treated animals had significantly smaller tumours compared to untreated, vehicle and positive control cisplatin-treated groups. This effect for DSF was independent of copper, with no significant accumulation of copper in tumours, together with maintained proteasome activity. However, increases in total ubiquitinated proteins, LC3B-II, LAMP1 and p62 in DSF and DSF/Met groups, indicate that autophagy is inhibited. These findings show that DSF and DSF/Met significantly impede OSCC tumour growth in vivo and offer prospective alternative chemotherapy approaches for OSCC.
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Affiliation(s)
- Rupal Jivan
- The School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, Private Bag X3, WITS 2050, South Africa
| | - Jade Peres
- Division of Cell Biology, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Observatory, Cape Town 7925, South Africa
| | - Leonard Howard Damelin
- The School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown 2193, South Africa; Cell Biology Group, Centre for HIV and STI's, National Institute for Communicable Diseases (NHLS), Private Bag X4, Sandringham, Johannesburg 2131, South Africa
| | - Reubina Wadee
- Division of Anatomical Pathology, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown 2193, South Africa
| | - Robin Bruce Veale
- The School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, Private Bag X3, WITS 2050, South Africa
| | - Sharon Prince
- Division of Cell Biology, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Observatory, Cape Town 7925, South Africa
| | - Demetra Mavri-Damelin
- The School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, Private Bag X3, WITS 2050, South Africa.
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4
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Hansson C, Pontén A, Svedman C, Bergendorff O. Reaction profile in patch testing with allergens formed during vulcanization of rubber. Contact Dermatitis 2014; 70:300-8. [DOI: 10.1111/cod.12168] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 09/12/2013] [Accepted: 09/25/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Christer Hansson
- Department of Dermatology; Skåne University Hospital; SE-221 85 Lund Sweden
| | - Ann Pontén
- Department of Occupational and Environmental Dermatology; Skåne University Hospital; SE-205 02 Malmö Sweden
| | - Cecilia Svedman
- Department of Occupational and Environmental Dermatology; Skåne University Hospital; SE-205 02 Malmö Sweden
| | - Ola Bergendorff
- Department of Dermatology; Skåne University Hospital; SE-221 85 Lund Sweden
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Madan A, Parkinson A, Faiman MD. Identification of the Human P-450 Enzymes Responsible for the Sulfoxidation and Thiono-Oxidation of Diethyldithiocarbamate Methyl Ester: Role of P-450 Enzymes in Disulfiram Bioactivation. Alcohol Clin Exp Res 1998. [DOI: 10.1111/j.1530-0277.1998.tb03901.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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6
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Hart BW, Faiman MD. Inhibition of rat liver low Km aldehyde dehydrogenase by thiocarbamate herbicides. Occupational implications. Biochem Pharmacol 1995; 49:157-63. [PMID: 7840792 DOI: 10.1016/s0006-2952(94)00491-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
S-Methyl N,N-diethylthiolcarbamate (DETC-Me) is a metabolite formed during the bioactivation of disulfiram. The formation of its corresponding sulfoxide, S-methyl N,N-diethylthiolcarbamate sulfoxide (DETC-MeSO), from DETC-Me is required for low Km mitochondrial aldehyde dehydrogenase (ALDH2, EC 1.2.1.3) inhibition. DETC-Me is similar in structure to thiocarbamate herbicides with the general structure R1R2NC(O)SR3. Representative herbicides studied were n-propyl, n-propylthiocarbamate ethyl ester (EPTC), molinate, vernolate, ethiolate and butylate. All of these thiocarbamate herbicides inhibited rat liver ALDH2 in vivo. The dose of these thiocarbamates that inhibited rat liver ALDH2 by 50% (ID50) when administered 8 hr before determination of ALDH2, was found to be 5.2, 3.1, 1.6, 12, and 174 mg/kg, respectively. These thiocarbamates were ineffective rat liver ALDH2 inhibitors in vitro, unless rat liver microsomes and an NADPH-generating system were added to the incubation. The respective thiocarbamate sulfoxides were formed when the thiocarbamates were incubated with liver microsomes and an NADPH-generating system. The thiocarbamate sulfoxides all inhibited rat liver ALDH2 in vitro. An equimolar dose of molinate and molinate sulfoxide inhibited rat liver ALDH2 in vivo to the same degree. Molinate-treated rats challenged with ethanol exhibited a disulfiram-like ethanol reaction. In conclusion, thiocarbamate herbicides inhibit ALDH2, probably due to the formation of their sulfoxide, and therefore have the potential to produce a disulfiram-like ethanol reaction in an unsuspecting population.
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Affiliation(s)
- B W Hart
- Department of Pharmacology and Toxicology, University of Kansas, Lawrence 66045
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7
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Madan A, Faiman MD. Diethyldithiocarbamate methyl ester sulfoxide, an inhibitor of rat liver mitochondrial low Km aldehyde dehydrogenase and putative metabolite of disulfiram. Alcohol Res 1994; 18:1013-7. [PMID: 7978080 DOI: 10.1111/j.1530-0277.1994.tb00075.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
S-methyl N,N-diethylthiolcarbamate sulfoxide (DETC-MeSO) is a potent inhibitor of rat liver mitochondrial low Km aldehyde dehydrogenase (ALDH2) both in vivo and in vitro, and has been proposed to be the metabolite responsible for ALDH2 inhibition by disulfiram. Diethyldithiocarbamate methyl ester (DDTC-Me), a key intermediate in the metabolism of disulfiram, has been shown to be bioactivated by microsomal monooxygenases to diethyldithiocarbamate methyl ester sulfoxide (DDTC-Me sulfoxide). Studies were conducted to determine if DDTC-Me sulfoxide was also an active metabolite of disulfiram and inhibitor of ALDH2. DDTC-Me sulfoxide inhibited ALDH2 in vitro with an IC50 of 10 microM, and in vivo with an ID50 of 31 mg/kg (170 mumol/kg). Maximal ALDH2 inhibition in vivo was observed 8 hr after the administration of 45.2 mg/kg DDTC-Me sulfoxide, with ALDH2 activity returning to control levels after 48 hr. Although DDTC-Me sulfoxide inhibited ALDH2 in vivo, DDTC-Me sulfoxide was not detected in plasma from rats treated with either disulfiram (75 mg/kg), DDTC-Me (122.25 mg/kg), or DDTC-Me sulfoxide (45.2 mg/kg). However, DDTC-Me and S-methyl N,N-diethylthiolcarbamate (DETC-Me) were detected in plasma from rats treated with DDTC-Me sulfoxide. In rats treated with DDTC-Me sulfoxide and challenged with ethanol, a small increase of approximately microM in blood acetaldhyde and an inconsistent drop in blood pressure was observed. In conclusion, DDTC-Me sulfoxide inhibited ALDH2 in vitro and in vivo, was less potent than DETC- MeSO, and was not detected after disulfiram administration.
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Affiliation(s)
- A Madan
- Department of Pharmacology and Toxicology, University of Kansas, Lawrence 66045
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8
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Hart BW, Faiman MD. In vivo pharmacodynamic studies of the disulfiram metabolite S-methyl N,N-diethylthiolcarbamate sulfoxide: inhibition of liver aldehyde dehydrogenase. Alcohol Clin Exp Res 1994; 18:340-5. [PMID: 8048736 DOI: 10.1111/j.1530-0277.1994.tb00023.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
S-methyl N,N-diethylthiolcarbamate sulfoxide (DETC-MeSO) is proposed to be the metabolite of disulfiram responsible for the in vivo inhibition of liver low Km aldehyde dehydrogenase (ALDH) in the rat. Studies were conducted in male Sprague-Dawley rats and also in vitro using both rat liver mitochondrial and purified bovine mitochondrial low Km ALDH to investigate further the pharmacodynamic and pharmacokinetic characteristics of DETC-MeSO. Administration of DETC-MeSO to rats produced a rapid and maximal inhibition of liver mitochondrial low Km ALDH within 2 hr, which was still inhibited 30% after 168 hr. After DETC-MeSO treatment, the maximum plasma concentration of DETC-MeSO was reached within 0.5 hr, with DETC-MeSO being undetectable 2 hr after DETC-MeSO dosing. Although a trace amount of DETC-Me was detected in the plasma 0.5 hr after DETC-MeSO administration to rats, this disappeared within 1 hr. When rats were treated with disulfiram, the maximal plasma concentration of DETC-MeSO was found within 2 hr, with only a very small quantity of DETC-MeSO still detectable after 8 hr. Rats also were given the disulfiram metabolites diethyldithiocarbamate (DDTC), diethyldithiocarbamate-methyl ester (DDTC-Me), and S-methyl N,N-diethylthiolcarbamate (DETC-Me), and plasma analyzed for DETC-MeSO 2 hr after the administration of these metabolites. DETC-MeSO was detected in plasma, further illustrating that DETC-MeSO can be found in plasma after the administration of either disulfiram, or the subsequent in vivo metabolites DDTC, DDTC-Me, or DETC-Me.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- B W Hart
- Department of Pharmacology and Toxicology, University of Kansas, Lawrence 66045
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9
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Hart BW, Faiman MD. Bioactivation of S-methyl N,N-diethylthiolcarbamate to S-methyl N,N-diethylthiolcarbamate sulfoxide. Implications for the role of cytochrome P450. Biochem Pharmacol 1993; 46:2285-90. [PMID: 8274162 DOI: 10.1016/0006-2952(93)90619-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Diethyldithiocarbamate (DDTC), diethyldithiocarbamate methyl ester (DDTC-Me), S-methyl N,N-diethylthiolcarbamate (DETC-Me) and S-methyl N,N-diethylthiolcarbamate sulfoxide (DETC-MeSO) are all metabolites of disulfiram. All inhibit rat liver low Km aldehyde dehydrogenase (ALDH) in vivo, with the order of potency being DETC-MeSO > DETC-Me > DDTC-Me > DDTC. Studies were carried out both in vivo and in vitro to further investigate the role of bioactivation as a requirement for the action of disulfiram as a liver ALDH inhibitor. The cytochrome P450 inhibitor 1-benzylimidazole (NBI) was employed as a pharmacological tool to study the metabolism of DETC-Me to DETC-MeSO. Administration of NBI to rats prior to DETC-Me treatment blocked the inhibition of liver mitochondrial low Km ALDH by DETC-Me. This was accompanied by an increase in plasma DETC-ME and a decrease in plasma DETC-MeSO. Pretreatment of rats with NBI prior to DETC-MeSO administration did not block the inhibition of liver mitochondrial low Km ALDH by DETC-MeSO. In in vitro studies, the inclusion of NBI in an incubation containing rat liver microsomes, mitochondria and an NADPH-generating system blocked the formation of DETC-MeSO and inhibition of liver mitochondrial low Km ALDH by DETC-Me. DETC-MeSO was found to be a potent inhibitor of rat liver mitochondrial low Km ALDH both in vivo and in vitro. The data suggest that the metabolism of DETC-Me to DETC-MeSO is mediated by cytochrome P450, and that inhibition of cytochrome P450 by inhibitors such as NBI block the inhibition of low Km ALDH by DETC-Me.
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Affiliation(s)
- B W Hart
- Department of Pharmacology and Toxicology, University of Kansas, Lawrence 66045
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10
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Abstract
Disulfiram (Antabuse) is one of several aldehyde dehydrogenase (ALDH) inhibitors that raise the plasma level of acetaldehyde following ethanol ingestion. The usually pleasant reaction to ethanol is thereby changed to an unpleasant one, owing to a number of bodily reactions to acetaldehyde. Populations showing genetic polymorphism with a lack of some isozymes of ALDH have exhibited an intolerance to ethanol similar to that seen with disulfiram. A normal isozyme pattern seems to be a prerequisite for the development of alcoholism, which supports the principle of disulfiram treatment. Disulfiram is an irreversible ALDH inhibitor when administered in vivo. Diethylthiomethylcarbamate (Me-DTC) is formed from disulfiram in three metabolic steps. This compound and two further oxidized metabolites appear to be active metabolites of disulfiram. Measurements of plasma Me-DTC or the reduction of leucocyte ALDH 1 activity may be valuable markers for the proper dose titration of disulfiram and the rational use of this drug. Some toxicological points are discussed.
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Affiliation(s)
- E N Petersen
- Department of Pharmacology, Dumex Ltd., Copenhagen
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11
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Hart BW, Faiman MD. In vitro and in vivo inhibition of rat liver aldehyde dehydrogenase by S-methyl N,N-diethylthiolcarbamate sulfoxide, a new metabolite of disulfiram. Biochem Pharmacol 1992; 43:403-6. [PMID: 1311578 DOI: 10.1016/0006-2952(92)90555-w] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In summary, these data provide the first evidence that DETC-MeSO is a natural metabolite of disulfiram, and a potent inhibitor of rat liver mitochondrial low Km ALDH both in vitro and in vivo. It is therefore proposed that, based upon evidence to date, DETC-MeSO appears to be the chemical species to which disulfiram must be bioactivated, and is the metabolite most likely responsible for disulfiram's inhibition of rat liver mitochondrial low Km ALDH in vivo. Characterization of the properties of DETC-MeSO as the metabolite responsible for disulfiram's action as an ALDH inhibitor is presently in the process of being completed.
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Affiliation(s)
- B W Hart
- Department of Pharmacology and Toxicology, University of Kansas, Lawrence 66045
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12
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Yourick JJ, Faiman MD. Disulfiram metabolism as a requirement for the inhibition of rat liver mitochondrial low Km aldehyde dehydrogenase. Biochem Pharmacol 1991; 42:1361-6. [PMID: 1656985 DOI: 10.1016/0006-2952(91)90446-c] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In humans and animals, disulfiram produces a disulfiram-ethanol reaction after an ethanol challenge, the basis of which is the inhibition of liver aldehyde dehydrogenase (ALDH). Disulfiram and the metabolites diethyldithiocarbamate (DDTC), diethyldithiocarbamate-methyl ester (DDTC-Me), and S-methyl-N,N-diethylthiolcarbamate (DETC-Me) were studied in order to determine the role of bioactivation in disulfiram's action as an inhibitor of rat liver mitochondrial low Km ALDH (RLM low Km ALDH). In in vitro studies, disulfiram and DDTC (0.01 to 2.0 mM) both inhibited RLM low Km ALDH in a concentration-dependent manner. The addition of rat liver microsomes to the mitochondrial incubation did not further increase disulfiram-induced RLM low Km ALDH inhibition. However, DDTC-induced RLM low Km ALDH inhibition was increased further, but only at DDTC concentrations less than 0.05 mM. DDTC-Me and DETC-Me (2.0 mM) similarly exhibited an increased RLM low Km ALDH inhibition after the addition of liver microsomes. In in vivo studies, disulfiram (75 mg/kg), DDTC (114 mg/kg), DDTC-Me (41.2 mg/kg) or DETC-Me (18.6 mg/kg) administered i.p. to female rats inhibited RLM low Km ALDH. Inhibition of drug metabolism by pretreatment of rats with the cytochrome P450 inhibitor N-octylimidazole (NOI) (20 mg/kg, i.p.) prior to either disulfiram, DDTC, DDTC-Me or DETC-Me administration blocked the inhibition of RLM low Km ALDH. The in vitro and in vivo data support the conclusion that bioactivation of disulfiram to a reactive chemical species is required for RLM low Km ALDH inhibition and a disulfiram-ethanol reaction.
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Affiliation(s)
- J J Yourick
- Department of Pharmacology and Toxicology, University of Kansas, Lawrence 66045
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13
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Kitson TM. Effect of some thiocarbamate compounds on aldehyde dehydrogenase and implications for the disulfiram ethanol reaction. Biochem J 1991; 278 ( Pt 1):189-92. [PMID: 1652937 PMCID: PMC1151466 DOI: 10.1042/bj2780189] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The effects of S-methyl diethyldithiocarbamate, S-methyl diethylmonothiocarbamate and bis(diethylcarbamoyl) disulphide on sheep liver cytoplasmic aldehyde dehydrogenase were investigated in vitro. The first compound has negligible effect. The second one is a weak inhibitor of the esterase activity of the enzyme and a weaker inhibitor of the dehydrogenase activity. A very low concentration of the third compound, however, acts as a potent inactivator of aldehyde dehydrogenase, similar in this respect to disulfiram, although somewhat slower to react. The possible involvement of these compounds in the physiological phenomenon known as the disulfiram ethanol reaction is discussed.
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Affiliation(s)
- T M Kitson
- Department of Chemistry and Biochemistry, Massey University, Palmerston North, New Zealand
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14
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Hart BW, Yourick JJ, Faiman MD. S-methyl-N,N-diethylthiolcarbamate: a disulfiram metabolite and potent rat liver mitochondrial low Km aldehyde dehydrogenase inhibitor. Alcohol 1990; 7:165-9. [PMID: 2158327 DOI: 10.1016/0741-8329(90)90079-r] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
S-methyl-N,N-diethylthiolcarbamate-methyl ester (DETC-Me), a proposed disulfiram metabolite, was investigated both in vivo and in vitro for its effectiveness as a liver mitochondrial low Km aldehyde dehydrogenase (L Km ALDH) inhibitor. Male Sprague-Dawley rats were treated intraperitoneally with DETC-Me, killed at various times and L Km ALDH determined. DETC-Me was found to be a more potent in vivo inhibitor of L Km ALDH than either disulfiram, diethyldithiocarbamate (DDTC) or diethyldithiocarbamate-methyl ester (DDTC-Me). The ID50 for DETC-Me, DDTC-Me and disulfiram was 6.5, 15.5 and 56.2 mg/kg, respectively. The ID50 for DDTC was similar to DDTC-Me. Maximal inhibition of L Km ALDH occurred 30 minutes after DETC-Me administration. DETC-Me was ineffective as an in vitro inhibitor. DETC-Me produced a marked disulfiram-ethanol reaction (DER) at one-quarter of the dose of disulfiram or DDTC. Plasma DETC-Me in rats was greater after DETC-Me administration than after DDTC-Me, DDTC or disulfiram. In conclusion, DETC-Me is proposed to be a metabolite of disulfiram, and may be the immediate precursor of the chemical species responsible for L Km ALDH inhibition.
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Affiliation(s)
- B W Hart
- Department of Pharmacology and Toxicology, University of Kansas, Lawrence 66045
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15
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Helander A, Carlsson S. Use of leukocyte aldehyde dehydrogenase activity to monitor inhibitory effect of disulfiram treatment. Alcohol Clin Exp Res 1990; 14:48-52. [PMID: 2178472 DOI: 10.1111/j.1530-0277.1990.tb00445.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Aldehyde dehydrogenase (ALDH; EC 1.2.1.3) activity was determined in leukocytes and erythrocytes from alcoholic patients during different stages of disulfiram (Antabuse) treatment. Assays were performed by incubating intact isolated blood cells in phosphate-buffered saline (pH 7.4, 37 degrees C), using 3,4-dihydroxyphenylacetaldehyde (DOPAL), the biogenic aldehyde derived from dopamine, as substrate. The ALDH activity was assessed from the amount of 3,4-dihydroxyphenylacetic acid (DOPAC) formed, as analysed by high-performance liquid chromatography with electrochemical detection. The leukocyte ALDH, which is similar to the liver "mitochondrial" low-Km ALDH isozyme, was maximally inhibited (about 40-60%) within 2 to 3 days after the initial disulfiram administration (dosage 200 or 400 mg/day orally). The time to reach maximum inhibition (about 95%) of the erythrocyte ALDH, which closely resembles the liver "cytosolic" high-Km isozyme, varied from 3 to more than 6 days. When medication was completed, the leukocyte ALDH activity remained unaltered for the first 2 days, and did not revert to normal levels until about 6 to 7 days after terminating treatment. The erythrocyte ALDH was still inhibited by about 90% 1 week after the last disulfiram administration. These results suggest that the leukocyte ALDH activity might provide an easily accessible marker for monitoring effect and time course of ALDH inhibition during disulfiram treatment.
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Affiliation(s)
- A Helander
- Department of Zoophysiology, Uppsala University, Sweden
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16
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Petersen EN. Pharmacological effects of diethylthiocarbamic acid methyl ester, the active metabolite of disulfiram? Eur J Pharmacol 1989; 166:419-25. [PMID: 2806369 DOI: 10.1016/0014-2999(89)90354-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A recently discovered metabolite, diethylthiocarbamic acid methyl ester (Me-DTC), has been found in the plasma of man and rats in much higher concentrations than any other described metabolite after therapeutic doses of disulfiram. Me-DTC, in contrast to other disulfiram metabolites, is a potent inhibitor of liver aldehyde dehydrogenase (ALDH) in vitro. Like disulfiram, Me-DTC had a pronounced hypothermic effect in rats. This hypothermic effect and the augmented blood pressure response to ethanol challenge in rats developed rapidly with Me-DTC but were somewhat delayed with disulfiram. The blood pressure response outlasted the presence of Me-DTC in plasma (less than 24 h); a significant effect was found 48 h after pretreatment but not 72 h after a single dose. No effect was observed when ethanol was given 15 min before Me-DTC or disulfiram. These latter two observations are consistent with a function of Me-DTC as a suicide inhibitor of ALDH. Since Me-DTC has been reported to inhibit ALDH in vitro, even under anaerobic conditions, Me-DTC may be the active metabolite of disulfiram.
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Affiliation(s)
- E N Petersen
- Department of Pharmacology, A/S Dumex, Copenhagen S, Denmark
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17
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Loomes KM, Kitson TM. Reaction between sheep liver mitochondrial aldehyde dehydrogenase and various thiol-modifying reagents. Biochem J 1989; 261:281-4. [PMID: 2775216 PMCID: PMC1138814 DOI: 10.1042/bj2610281] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Sheep liver mitochondrial aldehyde dehydrogenase reacts with 2,2'-dithiodipyridine and 4,4'-dithiodipyridine in a two-step process: an initial rapid labelling reaction is followed by slow displacement of the thiopyridone moiety. With the 4,4'-isomer the first step results in an activated form of the enzyme, which then loses activity simultaneously with loss of the label (as has been shown to occur with the cytoplasmic enzyme). With 2,2'-dithiodipyridine, however, neither of the two steps of the reaction has any effect on the enzymic activity, showing that the mitochondrial enzyme possesses two cysteine residues that must be more accessible or reactive (to this reagent at least) than the postulated catalytically essential residue. The symmetrical reagent 5,5'-dithiobis-(1-methyltetrazole) activates mitochondrial aldehyde dehydrogenase approximately 4-fold, whereas the smaller related compound methyl l-methyltetrazol-5-yl disulphide is a potent inactivator. These results support the involvement of mixed methyl disulphides in causing unpleasant physiological responses to ethanol after the ingestion of certain antibiotics.
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Affiliation(s)
- K M Loomes
- Department of Chemistry and Biochemistry, Massey University, Palmerston North, New Zealand
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Yourick JJ, Faiman MD. Comparative aspects of disulfiram and its metabolites in the disulfiram-ethanol reaction in the rat. Biochem Pharmacol 1989; 38:413-21. [PMID: 2537080 DOI: 10.1016/0006-2952(89)90380-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Diethyldithiocarbamate-methyl ester (DDTC-Me), a metabolite of disulfiram, has been shown recently to produce a disulfiram-ethanol reaction (DER). Studies were carried out to compare the ethanol-sensitizing properties of DDTC-Me with those of disulfiram and diethyldithiocarbamate (DDTC) in the rat. All three drugs inhibited liver mitochondrial low Km aldehyde dehydrogenase (ALDH) in vivo, with maximal ALDH inhibition occurring 8 hr after drug administration. The onset of ALDH inhibition was most rapid after DDTC-Me administration. ALDH was inhibited approximately 50% 0.5 hr after DDTC-Me, whereas ALDH was inhibited only 5 and 10%, respectively, after disulfiram and DDTC. Not until 8 hr after drug treatment was ALDH inhibition the same for disulfiram, DDTC and DDTC-Me. The degree of ALDH inhibition from 8 to 172 hr after dosing was the same for all three drugs. An ethanol (1 g/kg, 20% v/v) challenge administered to rats treated with disulfiram (75 mg/kg), DDTC (114 mg/kg), or DDTC-Me (41.2 mg/kg) for 8 hr produced similar blood acetaldehyde/ethanol concentration-time profiles. In addition, all three agents produced a DER (hypotension, tachycardia). No DER occurred if ethanol was administered more than 24 hr after drug pretreatment. The hypotension associated with the DER correlated with the increased blood acetaldehyde but not blood ethanol. A threshold blood acetaldehyde of 110 microM appeared to be required for hypotension to occur, and this was related to ALDH inhibition of approximately 40%. The tachycardia associated with the DER correlated more with blood ethanol. After DDTC-Me administration, no disulfiram or DDTC could be detected in the plasma. Furthermore, no DDTC-Me was found in the plasma 8 hr after DDTC-Me administration, suggesting that no correlation exists between the DER and plasma concentration of DDTC-Me and most likely disulfiram. These data suggest that the alcohol-sensitizing properties of DDTC-Me are similar to those observed with disulfiram and DDTC. Since DDTC-Me is an active metabolite and more potent than disulfiram and DDTC in producing a DER, disulfiram metabolism is an important consideration in the disulfiram-ethanol reaction.
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Affiliation(s)
- J J Yourick
- Department of Pharmacology and Toxicology, University of Kansas, Lawrence 66045
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