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Schrenk D, Bignami M, Bodin L, Chipman JK, del Mazo J, Hogstrand C, (Ron) Hoogenboom L, Leblanc J, Nebbia CS, Nielsen E, Ntzani E, Petersen A, Sand S, Schwerdtle T, Vleminckx C, Wallace H, Romualdo B, Cristina F, Stephen H, Marco I, Mosbach‐Schulz O, Riolo F, Christodoulidou A, Grasl‐Kraupp B. Risk assessment of N-nitrosamines in food. EFSA J 2023; 21:e07884. [PMID: 36999063 PMCID: PMC10043641 DOI: 10.2903/j.efsa.2023.7884] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023] Open
Abstract
EFSA was asked for a scientific opinion on the risks to public health related to the presence of N-nitrosamines (N-NAs) in food. The risk assessment was confined to those 10 carcinogenic N-NAs occurring in food (TCNAs), i.e. NDMA, NMEA, NDEA, NDPA, NDBA, NMA, NSAR, NMOR, NPIP and NPYR. N-NAs are genotoxic and induce liver tumours in rodents. The in vivo data available to derive potency factors are limited, and therefore, equal potency of TCNAs was assumed. The lower confidence limit of the benchmark dose at 10% (BMDL10) was 10 μg/kg body weight (bw) per day, derived from the incidence of rat liver tumours (benign and malignant) induced by NDEA and used in a margin of exposure (MOE) approach. Analytical results on the occurrence of N-NAs were extracted from the EFSA occurrence database (n = 2,817) and the literature (n = 4,003). Occurrence data were available for five food categories across TCNAs. Dietary exposure was assessed for two scenarios, excluding (scenario 1) and including (scenario 2) cooked unprocessed meat and fish. TCNAs exposure ranged from 0 to 208.9 ng/kg bw per day across surveys, age groups and scenarios. 'Meat and meat products' is the main food category contributing to TCNA exposure. MOEs ranged from 3,337 to 48 at the P95 exposure excluding some infant surveys with P95 exposure equal to zero. Two major uncertainties were (i) the high number of left censored data and (ii) the lack of data on important food categories. The CONTAM Panel concluded that the MOE for TCNAs at the P95 exposure is highly likely (98-100% certain) to be less than 10,000 for all age groups, which raises a health concern.
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Jeon D, Choi WM, Kim JS, Jung Y, Lee SY, Seo HR, Kim KM. Serum Sorbitol Dehydrogenase as a Novel Prognostic Factor for Hepatocellular Carcinoma after Surgical Resection. Cancers (Basel) 2021; 13:6143. [PMID: 34885252 PMCID: PMC8657083 DOI: 10.3390/cancers13236143] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 12/12/2022] Open
Abstract
The majority of patients with hepatocellular carcinoma (HCC) undergoing curative resection experience tumor recurrence. To examine the association between preoperative serum sorbitol dehydrogenase (SORD), a liver-derived enzyme that reflects liver damage, and recurrence of HCC after curative resection, 92 patients were randomly selected who underwent curative resection for HCC between 2011 and 2012 from a prospective registry. Recurrence-free survival (RFS) was compared based on serum SORD levels. Cox proportional hazard models were used to investigate prognostic factors for RFS. During a median follow-up duration of 57.1 months, 43 patients experienced HCC recurrence. Patients with serum SORD ≥15 ng/mL (HR, 3.46; 95% CI, 1.76-6.81; p < 0.001) had worse RFS compared with patients with serum SORD <15 ng/mL. Serum AFP and SORD levels were two independent prognostic factors for RFS. When patients were stratified by baseline serum SORD and AFP levels, patients with serum AFP levels ≥400 ng/mL and serum SORD levels ≥15 ng/mL had a distinctly poor prognosis with the lowest RFS rates (HR, 22.08; 95% CI, 6.91-70.50; p < 0.001). Baseline serum SORD is an effective prognostic factor for HCC after resection. It may help guide patient selection for surgery, especially when combined with serum AFP levels.
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Affiliation(s)
- Dongsub Jeon
- Department of Gastroenterology, Asan Liver Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea; (D.J.); (W.-M.C.); (J.-S.K.); (Y.J.)
| | - Won-Mook Choi
- Department of Gastroenterology, Asan Liver Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea; (D.J.); (W.-M.C.); (J.-S.K.); (Y.J.)
| | - Jin-Sun Kim
- Department of Gastroenterology, Asan Liver Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea; (D.J.); (W.-M.C.); (J.-S.K.); (Y.J.)
| | - Yusun Jung
- Department of Gastroenterology, Asan Liver Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea; (D.J.); (W.-M.C.); (J.-S.K.); (Y.J.)
| | - Su-Yeon Lee
- Advanced Biomedical Research Laboratory, Institut Pasteur Korea, Seongnam-si 13488, Korea;
| | - Haeng Ran Seo
- Advanced Biomedical Research Laboratory, Institut Pasteur Korea, Seongnam-si 13488, Korea;
| | - Kang Mo Kim
- Department of Gastroenterology, Asan Liver Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea; (D.J.); (W.-M.C.); (J.-S.K.); (Y.J.)
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Krishnakumar K, Ramadoss R, Krishnan R, Sukhija H. In vitro Quantification of Collagen and Snail1 Gene Expression in Experimentally Induced Fibrosis by Arecoline and Commercial Smokeless Tobacco Products. Asian Pac J Cancer Prev 2020; 21:1143-1148. [PMID: 32334483 PMCID: PMC7445985 DOI: 10.31557/apjcp.2020.21.4.1143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Indexed: 02/06/2023] Open
Abstract
INTRODUCTION Extracellular matrix component derangement is the major event in pathogenesis of Oral submucous fibrosis. Many studies have elaborated the alteration of the matrix components at a cellular and genetic level. However elaborate quantification of the components with varying concentrations of Areca nut extract and commercial tobacco products have not been done so far. MATERIALS AND METHODS Primary culture of tissues sourced during crown lengthening procedures were used for establishment of fibroblast monoculture and fibroblast / keratinocyte co-culture. Extracts of areca nut, commercial smokeless tobacco products (gutkha and haans) and control CCl4 were tested at concentrations ranging from 20 μL, 40 μL, 80 μL, 160 μL, 320 μL and time intervals of 12, 24, 48, 72 hours. Collagen quantification by spectrophotometry and SNAI1 gene expression study were done. RESULTS Extract of areca nut was found to show increased collagen production than commercial tobacco products and closely similar values to CCL4. Kruskal Wallis test was used to analyse the difference in collagen obtained. The mean values of collagen obtained in co-culture were lesser than those obtained in the fibroblast monoculture. SNAI1 gene expression was negative in both the culture experiments. CONCLUSION Areca nut extract was found to be more potent as an individual agent. Commercial smokeless tobacco products Gutka and Hans exhibited increased collagen production at higher concentration. These findings further steps up the persuasive ill effects of tobacco products. Negative SNAI1 gene expression was corroborated to lack of extracellular environment in the co coculture experiment.
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Affiliation(s)
| | - Ramya Ramadoss
- Department of Oral Pathology and Microbiology, SRM Dental College, SRM University, Chennai, India
| | - Rajkumar Krishnan
- Department of Oral Pathology and Microbiology, SRM Dental College, SRM University, Chennai, India
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8 Final Report on the Safety Assessment of Triethanolamine, Diethanolamine, and Monoethanolamine. ACTA ACUST UNITED AC 2016. [DOI: 10.3109/10915818309142006] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Triethanolamine (TEA), Diethanolamine (DEA), and Monoethanolamine (MEA) are amino alcohols used in cosmetic formulations as emulsifiers, thickeners, wetting agents, detergents, and alkalizing agents. The nitrosation of the etha-nolamines may result in the formation of N-nitrosodiethanolamine (NDELA) which is carcinogenic in laboratory animals. In single-dose oral toxicity for rats, TEA was practically nontoxic to slightly toxic, and DEA and MEA were slightly toxic. Long-term oral ingestion of the ethanolamines by rats and guinea pigs produced lesions limited mainly to the liver and kidney. Long-term cutaneous applications to animals of the ethanolamines also produced evidence of hepatic and renal damage. TEA and DEA showed little potential for rabbit skin irritation in acute and subchronic skin irritation tests. MEA was corrosive to rabbit skin at a 30% concentration in a single semioccluded patch application and at a >10% concentration in 10 open applications over a period of 14 days. The ethanolamines were nonmutagenic in the Ames test and TEA is also nonmutagenic to Bacillus subtilis. TEA did not cause DNA-damage inducible repair in an unscheduled DNA synthesis test. TEA had no carcinogenic or cocarcinogenic activity when dermally applied to mice for 18 months. Clinical skin testing of TEA and cosmetic products containing TEA and DEA showed mild skin irritation in concentrations above 5%. There was very little skin sensitization. There was no phototoxicity or photosensitization reactions with products containing up to 20.04% TEA. A formulation containing 11.47% MEA and a formulation containing 1.6% DEA and 5.9% MEA were irritating to human skin in patch tests. The Panel concludes that TEA, DEA, and MEA are safe for use in cosmetic formulations designed for discontinuous, brief use followed by thorough rinsing from the surface of the skin. In products intended for prolonged contact with the skin, the concentration of ethanolamines should not exceed 5%. MEA should be used only in rinse-off products. TEA and DEA should not be used in products containing N-nitrosating agents.
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Chen PJ, Chiu CH, Tseng JK, Yang KT, Chen YC. Ameliorative effects of D-glucuronolactone on oxidative stress and inflammatory/fibrogenic responses in livers of thioacetamide-treated rats. J Funct Foods 2015. [DOI: 10.1016/j.jff.2015.01.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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Babitha S, Banji D, Banji OJF. Antioxidant and hepatoprotective effects of flower extract of Millingtonia hortensis Linn. on carbon tetrachloride induced hepatotoxicity. J Pharm Bioallied Sci 2012; 4:307-12. [PMID: 23248564 PMCID: PMC3523526 DOI: 10.4103/0975-7406.103258] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 11/01/2011] [Accepted: 05/02/2012] [Indexed: 12/22/2022] Open
Abstract
Objective: Millingtonia hortensis Linn is an abundant resource of flavonoids, which might be beneficial in protecting liver tissue from injury. The hepatoprotective and antioxidant potential of ethanolic extract of M. hortensis on carbon tetrachloride (CCl4) induced hepatotoxicity and the possible mechanism involved therein were investigated in rats. Materials and Methods: Preliminary phytochemical studies were carried out to determine the total phenol and flavonoid contents. 30 adult Wistar rats were allocated into 5 groups. Control group received vehicle, group-2 received CCl4 alone (1 ml/kg body weight, intraperitonially), groups 3 - 5 received the ethanolic flower extract in 2 dose levels (200 and 400 mg/kg) and Curcumin (100 mg/kg) as a standard for 8 days orally, followed by CCl4 as a single dose on the 8th day. 48 hours later, blood was withdrawn, serum was subjected to biochemical assessments, and liver homogenate was examined for lipid peroxides, glutathione, superoxide dismutase, catalase and total protein levels. Furthermore, hepatic tissues were subjected to histopatological studies. Results: CCl4 treatment produced a profound increase in the levels of malondialdehyde, hepatic marker enzymes and bilirubin content compared with the control (P < 0.05). Pre-treatment with the flower extract of M. hortensis significantly enhanced the levels of endogenous antioxidants and reduced the levels of hepatic marker enzymes in relation to the CCl4 treated group (P < 0.05). Balloning degeneration and fatty changes in hepatocytes was prevented by pre-treatment with the flower extract. Conclusion: The antioxidant nature of the flower extract of M. hortensis could be responsible for averting damage to the liver.
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Affiliation(s)
- S Babitha
- Research Scholar, R and D Cell, JNTU, Hyderabad, India
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Luke NS, Sams R, DeVito MJ, Conolly RB, El-Masri HA. Development of a quantitative model incorporating key events in a hepatotoxic mode of action to predict tumor incidence. Toxicol Sci 2010; 115:253-66. [PMID: 20106946 DOI: 10.1093/toxsci/kfq021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Biologically based dose-response (BBDR) modeling of environmental pollutants can be utilized to inform the mode of action (MOA) by which compounds elicit adverse health effects. Chemicals that produce tumors are typically labeled as either genotoxic or nongenotoxic. Though both the genotoxic and the nongenotoxic MOA may be operative as a function of dose, it is important to note that the label informs but does not define a MOA. One commonly proposed MOA for nongenotoxic carcinogens is characterized by the key events cytotoxicity and regenerative proliferation. The increased division rate associated with such proliferation can cause an increase in the probability of mutations, which may result in tumor formation. We included these steps in a generalized computational pharmacodynamic (PD) model incorporating cytotoxicity as a MOA for three carcinogens (chloroform, CHCl(3); carbon tetrachloride, CCL(4); and N,N-dimethylformamide, DMF). For each compound, the BBDR model is composed of a chemical-specific physiologically based pharmacokinetic model linked to a PD model of cytotoxicity and cellular proliferation. The rate of proliferation is then linked to a clonal growth model to predict tumor incidences. Comparisons of the BBDR simulations and parameterizations across chemicals suggested that significant variation among the models for the three chemicals arises in a few parameters expected to be chemical specific (such as metabolism and cellular injury rate constants). Optimization of model parameters to tumor data for CCL(4) and DMF resulted in similar estimates for all parameters related to cytotoxicity and tumor incidences. However, optimization of the CHCl(3) data resulted in a higher estimate for one parameter (BD) related to death of initiated cells. This implies that additional steps beyond cytotoxicity leading to induced cellular proliferation can be quantitatively different among chemicals that share cytotoxicity as a hypothesized carcinogenic MOA.
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Affiliation(s)
- Nicholas S Luke
- Department of Mathematics, North Carolina Agricultural and Technical State University, Greensboro, North Carolina 27411, USA
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Ramachandran V, Raja B. Protective effects of syringic acid against acetaminophen-induced hepatic damage in albino rats. J Basic Clin Physiol Pharmacol 2010; 21:369-385. [PMID: 21305852 DOI: 10.1515/jbcpp.2010.21.4.369] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The protective effect of the phenolic compound syringic acid, one of the major benzoic acid derivatives from edible plants and fruits, was evaluated against acetaminophen (APAP)-induced hepatotoxicity in rats. Toxicity was induced in adult male albino Wistar rats by the administration of APAP (750 mg/kg body weight) intraperitoneally. Rats were treated with syringic acid (25, 50, and 100 mg/kg body weight) by the oral route. We assessed the activity of hepatic markers aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma-glutamyl transferase, and bilirubin. Lipid peroxidative markers thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides, and a decrease in enzymatic antioxidants superoxide dismutase, catalase, glutathione peroxidase, and non-enzymatic antioxidants vitamin C, vitamin E and reduced glutathione levels. Liver histology also showed convincing evidence regarding their protective nature against fatty changes induced during APAP intoxication. Syringic acid administered at a dose of 50 mg/kg body weight significantly decreased the activities of hepatic and renal function markers to near normal values when compared with the other two doses. The results suggest that syringic acid could afford a significant protective effect against APAP induced hepatic damage in rats.
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Affiliation(s)
- Vinayagam Ramachandran
- Department of Biochemistry and Biotechnology, Faculty of Science, Annamalai University, Annamalai nagar-608 002, Tamil Nadu, India.
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Jadhav SH, Sarkar SN, Patil RD, Tripathi HC. Effects of subchronic exposure via drinking water to a mixture of eight water-contaminating metals: a biochemical and histopathological study in male rats. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2007; 53:667-77. [PMID: 17882470 DOI: 10.1007/s00244-007-0031-0] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2007] [Accepted: 05/06/2007] [Indexed: 05/17/2023]
Abstract
In the current study, we examined whether subchronic exposure via drinking water to low doses of a mixture of metals (arsenic, cadmium, lead, mercury, chromium, manganese, iron, and nickel), found as contaminants in various water sources of India, and to concentrations equivalent to WHO maximum permissible limits (MPL) in drinking water for individual metals, can alter systemic physiology of male rats. Data on water contamination with metals in India were collected from the literature and metals were selected on the basis of their frequency of occurrence and contamination level above MPL. Male Wistar rats were exposed to the mixture at 0, 1, 10, and 100 times the mode concentrations (the most frequently occurring concentration) of the individual metals via drinking water for 90 days. One more group of rats was exposed to the mixture at a concentration equivalent to the MPL (WHO) in drinking water for individual metals. Toxic potential of the mixture was evaluated by assessing general toxicological end points, serum chemistry and histopathology of vital organs. The mixture decreased body weight and water consumption and increased weights of brain, liver, and kidneys with 10x and 100x doses. After 30 days of exposure, no appreciable changes were found in any blood clinical markers. After 60 days, only the 100x dose, while after 90 days both 10x and 100x doses increased activities of aspartate aminotransferase and alkaline phosphatase and levels of urea nitrogen and creatinine and decreased total protein and albumin levels, but alanine aminotransferase activity and glucose level were not affected. At 10x and 100x exposure levels, qualitatively similar, but dose-dependent vascular, degenerative, and necrotic changes were observed in brain, liver, and kidney. The results indicate that subchronic exposure to the metal mixture affected general health of male rats by altering the functional and structural integrity of kidney, liver, and brain at 10 and 100 times the mode concentrations of the individual metals in Indian water sources, but exposure at mode concentrations of contemporary water contamination levels or at concentrations equivalent to the MPL for individual metals in drinking water may not cause any health hazards in male rats.
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Affiliation(s)
- S H Jadhav
- Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, 243 122 Izatnagar, Uttar Pradesh, India
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DiSilvestro RA, Zhang W, DiSilvestro DJ. Kava feeding in rats does not cause liver injury nor enhance galactosamine-induced hepatitis. Food Chem Toxicol 2007; 45:1293-300. [PMID: 17353074 DOI: 10.1016/j.fct.2007.01.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2006] [Revised: 12/26/2006] [Accepted: 01/15/2007] [Indexed: 10/23/2022]
Abstract
Kava, like a number of herbals, has been associated with causing liver damage based on limited evidence. In contrast, the present study found that in rats, 3 mo feedings of two types of kava extracts (an acetone extract and an ethanol extract of the Samoan kava cultivar Ava Laau) at three different doses (31.25, 62.5 and 133 mg/kg diet) produced no liver injury based on serum markers of liver damage (sorbitol dehydrogenase activities, bile acid concentrations, and beta-glucuronidase activities) and serum lipid peroxide readings. In fact, for some measurements and some kava doses, the injury marker readings were below control values. Moreover, for these same parameters, kava feeding did not enhance the effects of the hepatotoxin galacatosamine (500 mg/kg ip); some kava doses even showed modest protection against liver injury. Liver histology analysis showed no signs of kava causing or enhancing liver injury. Thus, this study does not support the concept that kava produces or aggravates liver injury.
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Affiliation(s)
- Robert A DiSilvestro
- Human Nutrition, The Ohio State University, 345 Campbell Hall, 1787 Neil Avenue, Columbus, OH 43210-1295, United States.
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11
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Amacher DE, Adler R, Herath A, Townsend RR. Use of proteomic methods to identify serum biomarkers associated with rat liver toxicity or hypertrophy. Clin Chem 2005; 51:1796-803. [PMID: 16099942 DOI: 10.1373/clinchem.2005.049908] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Our objectives were to identify serum marker proteins in rats that might serve as sensitive indicators of hepatomegaly, hepatocellular necrosis, or hepatobiliary injury and to use them to analyze data from a collaborative proteomics project. METHODS In each of 4 studies comprising the collaborative project, rats were given 1 of 4 compounds that target the liver through different mechanisms. Sera and liver samples were collected by terminal bleeds at 1 of 3 postdose time points. Sera were depleted of major secretory proteins and then separated into protein features by 2-dimensional gel electrophoresis (2DGE). Liver specimens were also processed and subjected to 2DGE. Protein spots that significantly increased or decreased in quantity after drug treatment were recovered, digested, analyzed by mass spectroscopy, and compared with available databases for identification. Criteria for further consideration were (a) temporal expression (i.e., increase or decrease at early, fulminant, or recovery periods), (b) known biological function, (c) probable hepatic origin, and (d) any previous association with toxicity in published studies. Markers that changed significantly at the early time point were important because of their potential sensitivity for signaling minimal damage. RESULTS Vitamin D-binding protein, paraoxonase, cellular retinol-binding protein, malate dehydrogenase, F-protein, and purine nucleoside phosphorylase were identified as empirically confirmed serum markers for hepatic effects in drug-treated rats. CONCLUSION Proteomics can be applied for the identification and confirmation of peripheral biomarkers for altered liver function after toxicant exposure.
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Affiliation(s)
- David E Amacher
- Molecular & Investigative Toxicology, World Wide Safety Sciences, Pfizer Inc., Groton, CT 06340, USA.
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Abstract
Biological markers (biomarkers) are used to recognize, characterize and monitor treatment-related responses following exposure to xenobiotics. Biomarkers serve three primary applications in toxicology: 1) to confirm exposure to a deleterious agent, 2) to provide a system for monitoring individual susceptibility to a toxicant, and 3) to quantitatively assess deleterious effects of a toxicant to an organism or individual. Because the liver is a general target for adverse effects of drugs and other chemicals, biomarkers of untoward hepatic response to xenobiotics are of particular interest to the pharmaceutical toxicologist. General requirements for the latter category of biomarkers are sample availability, target organ specificity, sensitivity for the toxicity of interest, accessibility, a relatively short half-life, and available detection systems. Biomarkers that can be assayed in biological fluids from both human and animal subjects are particularly desirable. Histologically, acute and subacute hepatic toxicity commonly involves necrosis, steatosis, cholestasis, vascular disorders, or multiple lesions. The purpose of this review is to summarize reported applications using clinical analytes and biochemical indicators of hepatic dysfunction with emphasis on those that show promise of supplementing or improving upon standard laboratory procedures. Liver function markers refer to peripheral indicators of hepatic synthetic and secretory activities, enterohepatic function, or perturbations of the hepatic uptake and clearance of circulating biomolecules. Liver injury biomarkers include various peripheral proteins released in response to a cellular damage or locally, proteins that are significantly altered within the liver. These include both circulating cytosolic, mitochondrial, or canalicular membrane markers, and the up-regulation or depletion of radical scavengers, modulators, and stabilizers of intracellular damage. Subsequent recovery from a toxic insult involves repair, regenerative, and proliferative responses that constitute the third class of biomarkers. Of these, protein markers found either in sera, plasma, or urine either during or just prior to the early manifestation of histological hepatic lesions are of greatest interest. Examples of a number of these markers, their documented applications in humans or animals, and potential advantages as well as limitations are presented.
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Affiliation(s)
- D E Amacher
- Drug Safety Evaluation, Pfizer Global Research and Development, Groton, Connecticut 06340, USA.
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Abstract
The objective of this study was to develop and describe an experimental canine model of multiple acquired portosystemic shunts (PSS) similar in nature to spontaneously occurring PSS. Sixteen dogs were used and were divided into a control (n = 6) and a diseased group (n = 10). Dogs of the diseased group were administered dimethylnitrosamine (2 mg/kg of body weight, po) twice weekly, and clinicopathologic, ultrasonographic, and hepatic scintigraphic findings were recorded during the development of hepatic disease and PSS. Surgery was then performed to permit visual verification of multiple shunts, catheter placement for portography examination, and biopsy of the liver. All diseased dogs developed severe hepatic disease and multiple PSS as documented visually at surgery and on portography. Based on this study, dimethylnitrosamine-induced portosystemic shunting appears to be an appropriate model for spontaneously occurring multiple PSS secondary to portal hypertension.
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Affiliation(s)
- L M Howe
- Department of Small Animal Medicine and Surgery, Texas Veterinary Medical Center, Texas A&M University, College Station 77843-4474, USA
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Ladics GS, Smith C, Elliott GS, Slone TW, Loveless SE. Further evaluation of the incorporation of an immunotoxicological functional assay for assessing humoral immunity for hazard identification purposes in rats in a standard toxicology study. Toxicology 1998; 126:137-52. [PMID: 9620545 DOI: 10.1016/s0300-483x(97)00179-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A previous study (Ladics et al., 1995) conducted in our laboratory using the known immunosuppressant agent, cyclophosphamide, indicated that a functional assay for assessment of humoral immunity may be conducted in rats in a standard toxicology study. The objective of this study was to further examine the feasibility of conducting an immunotoxicological assay for assessing humoral immunity in rats in a standard toxicology study using a chemical, carbon tetrachloride (CCl4), whose principal target organ of toxicity is not the immune system. Specifically, the previous study and this study were done to determine whether the conduct of an assay for assessing humoral immune function would affect standard toxicological endpoints. Male CD rats were untreated or dosed orally for 30 or 90 days, excluding weekends, with vehicle or 12.5 or 25 mg/kg CCl4. Six days prior to sacrifice, selected rats were injected intravenously with sheep red blood cells (SRBC) for assessment of humoral immune function. One day prior to necropsy, blood for hematological and clinical chemical measurements was collected from each rat. On the day of necropsy standard protocol tissues were collected, weighed, processed to slides, and later examined microscopically. One-half of each spleen was used to assess spleen cell numbers and quantitate lymphocyte subsets (Thelper; Tcyt/sup; total T- and B-cells) by flow cytometry. Serum was analyzed for anti-SRBC IgM antibody by using an enzyme-linked immunosorbent assay. Administration of 12.5 and 25 mg/kg CCl4 for 30 days decreased SRBC-specific serum IgM levels 42 and 45%, respectively, while 25 mg/kg CCl4 for 90 days increased SRBC-specific IgM levels by 50%. CCl4 did not alter splenic lymphocyte subset numbers nor the weight nor morphology of lymphoid organs. Exposure to 25 mg/kg CCl4 did increase liver weight and serum sorbitol dehydrogenase levels, as well as produce centrilobular fatty change. SRBC administration did not alter any hematological or clinical chemistry parameters, nor lymphocyte subset numbers. With the expected exception of the spleen (slight increase in number and size of germinal centers), administration of SRBC did not significantly alter the weights or morphology of routine protocol tissues. Furthermore, administration of SRBC did not mask the rather mild hepatotoxic effects of CCL4 exposure observed in this study. Based on these and previous findings, it appears that a functional assay for assessing humoral immunity may be conducted in animals on standard toxicology study without altering standard toxicological endpoints.
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Affiliation(s)
- G S Ladics
- E.I. du Pont de Nemours and Co., Haskell Laboratory for Toxicology and Industrial Medicine, Newark, DE 19714, USA
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Abstract
To confirm an earlier report that laboratory rats are susceptible to infection with the hepatitis E virus (HEV), we inoculated 27 Wistar rats intravenously with a suspension of a human stool known to contain infectious HEV. Stool, sera, and various tissues were collected from three rats each on days 0 (preinoculation) and 4, 7, 11, 14, 18, 21, 25, 28, and 35 postinoculation. Stool and sera specimens were examined by reverse transcription-polymerase chain reaction for the presence of HEV genomic sequences. Tissues were examined by light microscopy for detection of histopathological changes and by direct immunofluorescence for detection of HEV antigens. We detected HEV RNA in stools on day 7 in all three animals and in serum intermittently between days 4 and 35. We found HEV antigens in liver, peripheral blood mononuclear cells, spleen, mesenteric lymph nodes, and small intestine. We detected histopathology attributable to the inoculum in liver, spleen, and lymph nodes. The results confirm that HEV can replicate in laboratory rats and suggest new tissue sites for HEV replication.
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Affiliation(s)
- Y Maneerat
- Department of Pathobiology, Mahidol University, Bangkok, Thailand
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Travlos GS, Morris RW, Elwell MR, Duke A, Rosenblum S, Thompson MB. Frequency and relationships of clinical chemistry and liver and kidney histopathology findings in 13-week toxicity studies in rats. Toxicology 1996; 107:17-29. [PMID: 8597028 DOI: 10.1016/0300-483x(95)03197-n] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The relative sensitivities of eight commonly used clinical chemistry end points and histopathology to detect potential toxic effects in liver and kidney were evaluated for a series of 61 13-week rat toxicity studies conducted for the National Toxicology Program. The data consisted of 1-,2- to 3-, and 13 week clinical chemistry measurements and 13-week histopathological assessments of liver and kidney. Except for serum alkaline phosphatase, treatment-related alterations of individual clinical chemistry variables occurred in 20-48% of the studies, depending on the analyte, sampling time, and sex. Liver and kidney lesions were reported for 31% and 41% of the studies respectively. There was an association between treatment-related increases in alanine aminotransferase (ALT) and sorbitol dehydrogenase (SDH) activities and histopathological changes in the liver. SDH activity had greater positive and negative predictive values than similar changes in ALT; by week 1 in females and weeks 2-3 in both sexes. SDH predicted morphological hepatic change at study termination with 75% or better accuracy. If increases in activities of both enzymes occurred simultaneously, however, terminal histopathological changes could be predicted, in both sexes, with 75% accuracy by week 1, increasing to 100% by weeks 2-3. There also was an association between treatment-related increases in urea nitrogen (UN) and creatinine (Cre) concentrations and morphological kidney change. Cre concentration had greater positive predictive values than similar changes in UN; by weeks 2-3 in males and week 13 in both sexes. Cre predicted morphological renal change at study termination with 56% or better accuracy. UN concentration was associated and predictive of morphological kidney change only in females at week 13. Depending on time point and sex, serum alkaline phosphatase activity increased in 5-22% of the studies. Increases in total bile acid concentration occurred in 33-48% of the studies. Because both tests are used as markers of cholestasis, this marked discrepancy was unexpected. Treatment-related decreases in alkaline phosphatase activity occurred, however, in 39-56% of the studies; serum alkaline phosphatase may be more useful as an indicator of decreased food intake (decreased activity) than of cholestasis (increased activity). In summary, treatment-related alterations of clinical chemistry and histopathology occurred frequently in this series of toxicity studies in rats. Changes in the chemistry end points also occurred frequently at interim time points, indicating that clinical chemistry evaluations can be useful for detecting potential treatment effects throughout a study. This observation is important, since histopathological evaluations are limited to animal termination and not useful for detecting transient responses or the onset of treatment-related effects.
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Affiliation(s)
- G S Travlos
- Laboratory of Experimental Pathology, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, USA
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17
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Vandenberghe Y, Masson M, Palate B, Roba J. Effect of folate supplementation on clinical chemistry and hematologic changes related to bidisomide administration in the rat. Drug Chem Toxicol 1995; 18:235-70. [PMID: 8586020 DOI: 10.3109/01480549509014323] [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: 01/31/2023]
Abstract
In a chronic toxicity study in the rat, bidisomide administered as a dietary admixture produced a dose-related lowering of reticulocytes and leucocytes. Plasma alanine aminotransferase activity was increased at 300 mg/kg and decreased at 900 mg/kg. The potential mechanisms of these effects were investigated by comparing the responses in groups of male Sprague-Dawley rats receiving a control diet, or 300 or 1200 mg/kg/day bidisomide. Subsets of these groups were co-treated subcutaneously with folinic acid or with a vitamin B1, B6, B12 complex. Subsets of control and 300 mg/kg groups were maintained on a 20-25% feed restriction regimen for 3 months, to mimic the depression in body weight gain observed in animals receiving 1200 mg/kg. Body weight gains were significantly reduced at 1200 mg/kg and in all feed-restricted animals. Plasma and liver alanine aminotransferase (ALT) and plasma aspartate aminotransferase (AST) levels were also reduced at this dose level. At 300 mg/kg, plasma transaminases, glutamate dehydrogenase (GLDH) and sorbitol dehydrogenase (SDH) activities were increased. These changes were prevented in animals receiving folinic acid supplementation. Plasma glucose, triglycerides, and unsaturated and total iron binding capacities were decreased, while plasma iron levels tended to increase, mainly at the high dose. Vitamin supplementation prevented a decrease in reticulocyte counts at 300 mg/kg. Bidisomide increased urinary formimino-glutamic acid (FIGLU) excretion but did not affect methylmalonic acid (MMA) or taurine excretion. The effect on FIGLU at 1200 mg/kg was prevented by folinic acid co-treatment. Absolute liver weight was lowered at both dose levels and in feed-restricted animals. However, the relative liver weights were unaffected. Thymidine kinase and thymidylate synthase activity of the bone marrow cells were not altered by the bidisomide treatment. Except for the increase in plasma transaminase, GLDH and SDH levels at 300 mg/kg, changes in clinical chemistry parameters are considered to result mainly from nutritional restrictions. Changes in hematologic parameters appear to be related to the combination of decreased feed consumption (leukocytes) and decreased availability or utilization of folates (reticulocytes). This alteration, however, did not affect DNA synthesis in bone marrow. The prevention by folinic acid, but not by feed restriction, of the elevation of liver enzymes at 300 mg/kg is an intriguing, yet unexplained finding. There was no evidence that bidisomide affected B6 and B12 availability.
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Affiliation(s)
- Y Vandenberghe
- Department of Product Safety, Searle European Development Centre, Mont-St-Guibert, Belgium
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18
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Melnick RL, Mahler J, Bucher JR, Thompson M, Hejtmancik M, Ryan MJ, Mezza LE. Toxicity of diethanolamine. 1. Drinking water and topical application exposures in F344 rats. J Appl Toxicol 1994; 14:1-9. [PMID: 8157863 DOI: 10.1002/jat.2550140103] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Toxicology studies of diethanolamine were conducted in male and female F344 rats for 13 weeks' duration to characterize and compare effects of exposure in the drinking water with those caused by topical application. Doses of diethanolamine ranged from 160 to 5000 ppm in the drinking water study (equivalent to daily doses of 25-440 mg kg-1 in males and 15-240 mg kg-1 in females) and from 32 to 500 mg kg-1 in the topical application study. Dose-dependent toxic effects due to exposure to diethanolamine included hematological changes (a poorly regenerative, microcytic anemia), as well as toxic responses in the kidney (increased weight, tubular necrosis, decreased renal function, and/or tubular mineralization), brain and spinal cord (demyelination), testis (degeneration of the seminiferous tubules) and skin (site of application: ulceration, inflammation, hyperkeratosis and acanthosis). A no-observed-adverse-effect level was not achieved for hematological changes, nephropathy or hyperkeratosis of the skin. Differences in dose-response between the drinking water and topical application exposures were attributed largely to the limited dermal absorption of this chemical.
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Affiliation(s)
- R L Melnick
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709
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19
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Melnick RL, Mahler J, Bucher JR, Hejtmancik M, Singer A, Persing RL. Toxicity of diethanolamine. 2. Drinking water and topical application exposures in B6C3F1 mice. J Appl Toxicol 1994; 14:11-9. [PMID: 8157864 DOI: 10.1002/jat.2550140104] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Toxicology studies of diethanolamine were conducted in male and female B6C3F1 mice to characterize and compare effects of exposure in the drinking water with those caused by topical application and to compare responses in mice to those observed in rats. Each study consisted of five dose groups plus controls and the size of each group was 10 animals per sex. Doses of diethanolamine ranged from 630 to 10,000 ppm in the drinking water study (approximately equivalent to daily doses of 100-1700 mg kg-1 in males and 140-1100 mg kg-1 in females) and from 80 to 1250 mg kg-1 in the topical application study. Exposure to diethanolamine caused dose-dependent toxic effects in the liver (hepatocellular cytological alterations and necrosis), kidney (nephropathy and tubular epithelial necrosis in males), heart (cardiac myocyte degeneration) and skin (site of application: ulceration, inflammation, hyperkeratosis, and acanthosis). Cytological alterations in the liver consisted of multiple hepatocyte changes, including enlarged cells that were frequently multinucleated, increased nuclear pleomorphism, increased eosinophilia and disruption of hepatic cords. A no-observed-adverse-effect level (NOAEL) was not achieved for hepatocellular cytological alterations or for acanthosis in the skin.
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Affiliation(s)
- R L Melnick
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709
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20
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Szymańska JA, Swietlicka EA, Piotrowski JK. Protective effect of zinc in the hepatotoxicity of bromobenzene and acetaminophen. Toxicology 1991; 66:81-91. [PMID: 1996469 DOI: 10.1016/0300-483x(91)90180-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Mice of the Balb'c strain were administered bromobenzene (BB) or acetaminophen (AA) i.p., in single doses of 400 and 300 mg/kg, respectively. In the blood activity of SGOT and SGPT as well as SDH was determined. In the liver the level of metallothionein (MT), malondialdehyde (MDA) and glutathione (GSH) was measured. The level of MT as well as GSH (determined as non-protein SH groups) showed a significant increase following administration of zinc alone. Joint action of zinc and either BB or AA resulted in a decrease of GSH which was less pronounced than expected for each of the xenobiotics alone. The protective effect of zinc reflected in the reduction of the increase of SGPT and SGOT activity was apparent shortly (4 h) after administration of AA. A day after injection of AA alone the activity of enzymes was lower and the rate of decline followed the sequence SGPT greater than SGOT greater than SDH. For BB, both the toxic effect and the protective influence of zinc were apparent 24 h following administration. At 4 h in a group receiving BB alone no changes of the indicatory enzymes in blood were noted.
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Affiliation(s)
- J A Szymańska
- Department of Toxicological Chemistry, Medical Academy, Lódź, Poland
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21
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Hewitt LA, Palmason C, Masson S, Plaa GL. Evidence for the involvement of organelles in the mechanism of ketone-potentiated chloroform-induced hepatotoxicity. LIVER 1990; 10:35-48. [PMID: 2308479 DOI: 10.1111/j.1600-0676.1990.tb00433.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Ketones can potentiate the hepatotoxicity of haloalkanes in animals. This may be due, in part, to changes in organelle susceptibility. Male Sprague-Dawley rats were administered 15 mmol/kg (po) acetone, 2-butanone, 2-hexanone or 50 mg/kg (po) chlordecone or mirex (a nonketonic analog of chlordecone). Eighteen hours later, tests of organelle structure/function were performed (osmotic stress, respiration, and calcium pump activity). Other rats were given 14CHCl3 (0.5 or 1.0 ml/kg, po) 18 h after chlordecone or mirex administration. Three hours later, the organelle distribution of 14C was evaluated. In a final experiment, ketone-pretreated (chlordecone or 2-hexanone) animals were killed 6 h after CHCl3 administration and evaluated morphologically for evidence of modified organelle response. Acetone and chlordecone, when given alone, enhanced lysosomal fragility to osmotic stress; no changes in functional capacity of mitochondria or microsomes were observed. CHCl3-derived 14C in the mitochondrial fraction increased 2-fold in chlordecone-treated rats. Morphological evaluation suggested mitochondria respond differently to CHCl3 in ketone-pretreated (chlordecone or 2-hexanone) animals compared to corn oil-pretreated controls. These results support the concept that modifications of organelles contribute to the mechanism of ketone-potentiation of CHCl3-induced hepatotoxicity.
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Affiliation(s)
- L A Hewitt
- Department of Pharmacology, Faculty of Medicine, University of Montreal, Quebec, Canada
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22
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Strubelt O, Younes M, Pentz R. Enhancement by glutathione depletion of ethanol-induced acute hepatotoxicity in vitro and in vivo. Toxicology 1987; 45:213-23. [PMID: 3603586 DOI: 10.1016/0300-483x(87)90107-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Ethanol at initial concentrations between 0.75 and 6 g/l produced a dose-dependent release of the enzymes glutamic-pyruvic-transaminase and sorbitol dehydrogenase (GPT, SDH) from the isolated perfused rat liver. At the concentration of 6 g/l, it also decreased the oxygen consumption and elevated the calcium content of the isolated livers. These toxic effects of ethanol were significantly enhanced in livers, the glutathione content of which had been depleted by pretreatment with phorone. Ethanol-induced toxicity in glutathione-depleted isolated livers could be prevented both by inhibition of alcohol dehydrogenase with 4-methylpyrazole and of xanthine oxidase with allopurinol. In rats, in vivo, 1.6 g/kg ethanol injected intravenously produced a small increase in serum GPT and SDH concentrations 4 h after its administration. This increase in enzyme activities was several-fold higher and longer lasting in rats pretreated with phorone. Glutathione depletion per se did not induce hepatotoxicity in vitro or in vivo. Since glutathione is involved in several lines of defense against oxidative damage, our results of an enhanced susceptibility of glutathione-depleted livers to ethanol toxicity favour the hypothesis that ethanol exerts its hepatotoxic action via an activation of molecular oxygen.
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23
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Pilon D, Brodeur J, Plaa GL. 1,3-Butanediol-induced increases in ketone bodies and potentiation of CCl4 hepatotoxicity. Toxicology 1986; 40:165-80. [PMID: 3726892 DOI: 10.1016/0300-483x(86)90076-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Evidence previously reported suggest that 1,3-butanediol (BD) enhances the hepatotoxic effect of a single small dose of carbon tetrachloride (CCl4) in a dose-related manner. The present study provides additional information concerning the quantitative relationship between the severity of the ketotic state produced by BD and the magnitude of the potentiation observed and emphasizes the use of ketone bodies (KB) to predict the potential hazard of the BD-CCl4 interaction. Liver damage was modulated in male Sprague-Dawley rats by varying the concentration of the BD solutions ingested prior to a CCl4 challenge (0.1 ml/kg, i.p.). These data were compared to ketone bodies in plasma, hepatic tissue and urine. BD produced a dose-dependent metabolic ketosis observable at dosages between 1.1 and 9.9 g/kg per day given for 7 days. Plasma and liver data correlated well together. Concomitantly, potentiation of the CCl4-induced liver injury was also dose-related for the same dosage range; the minimum effective dosage of BD for potentiation was estimated as 1.1 g/kg per day. The linear correlations between hepatic or plasma KB values and the indices of hepatic dysfunction (ALT, OCT) were highly significant. Using a semiquantitative method, a correlation was also found for the urinary KB data. These results suggest that plasma KB concentrations might be useful for predicting possible potentiation of the hepatonecrotic effect of CCl4 by BD.
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24
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Carakostas MC, Gossett KA, Church GE, Cleghorn BL. Evaluating toxin-induced hepatic injury in rats by laboratory results and discriminant analysis. Vet Pathol 1986; 23:264-9. [PMID: 3014705 DOI: 10.1177/030098588602300306] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The ability of 14 serum biochemical assays to predict the presence of hepatic necrosis induced by carbon tetrachloride (CCl4) (centrilobular necrosis), allyl alcohol (periportal necrosis), and 1-napththylisothiocyanate (ANIT) (biliary duct necrosis) was evaluated in rats. Results of these assays were analyzed using multivariate discriminant analysis to determine: which assays have the highest predictive value for discriminating between control and treated rats, and which assays would discriminate between rats in the three treatment groups. Individual assays with the highest predictive value for CCl4-induced lesions versus controls were glutamate dehydrogenase (GDH), sorbitol dehydrogenase (SDH), and alanine aminotransferase (ALT). Assays with the highest predictive value for ANIT-induced lesions were GDH, 5'-nucleotidase (5'NT), and ALT. Assays the highest predictive value for ANIT-induced lesions were GDH, 5'-nucleotidase (5'NT), and ALT. Assays with the highest predictive value for allyl alcohol-induced lesions were an ALT/isocitrate dehydrogenase (ICD) ratio, GDH, and ALT. Canonical correlation coefficients for each assay ranged from 0.98 to 0.91 with 95-100% correct group membership predictions (treated versus control) provided by each assay. Individual assays were not highly predictive for determining group membership among all three treatment groups. A two assay combination of 5'NT and an ALT/ICD ratio provided 100% correct group membership predictions and had high canonical correlations (f1 = 0.95, f2 = 0.83).
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25
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Dahab GM, Gerges SE, Abdel-Rahman MS. Effect of benzyl chloride on rat liver functions. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 1986; 18:431-9. [PMID: 3712500 DOI: 10.1080/15287398609530883] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Benzyl chloride (BCL) is extensively used in industry for the manufacture of dyes, perfumes, and pharmaceutical products. A previous study from this laboratory revealed the presence of liver steatosis of the microvesicular type and central focal inflammation in rats following the inhalation of BCL. This study was conducted to investigate the hepatotoxicity of intravenous (iv) BCL in rat. BCL (250, 25, and 0 micrograms/kg) was administered (iv) to rats, and serum enzyme tests were used to evaluate hepatic injury. After 10 min from BCL administration, serum glutamic-pyruvic transaminase and lactic dehydrogenase activities were significantly increased compared to the control group, while the values returned to normal within 1 h from the administration of BCL. Also, ornithine carbamyltransferase enzyme activity was significantly increased and reached a maximum as early as 0.5 h from the administration of BCL. Hepatic excretory function was investigated by the clearance of bromosulfophthalein (BSP) after 0.5 and 24 h from the administration of BCL. The clearance of BSP in both treatments was significantly slower compared to control group throughout the 24 h studied. Furthermore, BCL significantly decreased liver and blood glutathione values. This study revealed that BCL has the potential to cause hepatomalfunction.
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26
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Charbonneau M, Iijima M, Côté MG, Plaa GL. Temporal analysis of rat liver injury following potentiation of carbon tetrachloride hepatotoxicity with ketonic or ketogenic compounds. Toxicology 1985; 35:95-112. [PMID: 4002241 DOI: 10.1016/0300-483x(85)90025-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The administration of some ketonic or ketogenic compounds prior to a challenging dose of CCl4 potentiates the hepatic damage induced by this haloalkane. However, nothing is known about the recovery from the liver injury in these cases of chemically induced potentiation. To investigate this problem, we performed a temporal analysis of the hepatotoxic response of male Sprague-Dawley rats to CCl4 following a single pretreatment (p.o.) with: n-hexane, 2-hexanone, 2,5-hexanedione (15 mmol/kg in corn oil), isopropanol, acetone (33 and 34 mmol/kg in water, respectively); or the vehicle alone (10 ml/kg). They received, 18 h later, an i.p. injection of CCl4 (0.1, 0.75 or 1.0 ml/kg) and were killed 24-120 h later. Liver damage was assessed biochemically (ALT, OCT) and morphologically. A good correlation between biochemical and morphological results was observed. The ketonic or ketogenic compounds studied potentiated the liver injury produced by 0.1 ml/kg CCl4. Relative ranking orders regarding severity of maximal hepatic damage induced and time needed for complete recovery of liver injury were established; time of recovery was dependent on the maximal severity of the lesion, regardless of the potentiation. The results show that the temporal evolution of CCl4-induced liver injury is not markedly influenced by the administration of ketonic or ketogenic compounds as pretreatments, but rather depends on the severity of the maximal damage induced by the overall treatment.
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27
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Carrillo MC, Rodriguez JV, Monti JA, Rodriguez Garay EA. Hepatic transport and biliary excretion of sulfobromophthalein in aflatoxin B1-treated rats. Toxicol Appl Pharmacol 1985; 77:353-7. [PMID: 3919465 DOI: 10.1016/0041-008x(85)90335-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The effects of a single dose of aflatoxin B1 (AFB1) on sulfobromophthalein (BSP) plasma disappearance, hepatic transport maximum (Tm), and relative storage capacity (S), were examined in rats 48 hr after AFB1 injection. BSP plasma concentration decay was delayed, and the BSP biliary excretion was diminished in treated animals. S and Tm values were unaltered. However, the Tm was reached in treated rats at a higher infusion rate. A Lineweaver-Burk plot of BSP biliary excretion rate vs BSP serum concentration curve showed a higher apparent Km in the AFB1-treated rats.
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28
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Whitby H, Gescher A, Levy L. An investigation of the mechanism of hepatotoxicity of the antitumour agent N-methylformamide in mice. Biochem Pharmacol 1984; 33:295-302. [PMID: 6704151 DOI: 10.1016/0006-2952(84)90488-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
N-Methylformamide (NMF) has been reported to cause liver damage in animals and man. This hepatotoxicity was characterized in BALB/c mice by the release of liver enzymes into the plasma and by histopathological examination of livers after single and repeated administration of NMF. Whereas plasma levels of sorbitol dehydrogenase were elevated dramatically 24 hr after 400 mg/kg given as a single dose, the glutathione content of the livers was not different from controls even after repeated administration. Liver damage was apparent on gross inspection and was defined as periacinar necrosis on histopathology. A dose of 100 mg/kg did not cause damage even after repeated injections on five consecutive days. The hypothesis that NMF is metabolized to a chemically reactive species was tested. Incubation of mouse hepatocytes with 7 mM NMF for 80 min produced a decrease in intracellular glutathione. Exposure of hepatocytes to NMF for 240 min led to the production of breakdown products of lipid peroxides at levels significantly above controls. However, incubation of microsomes or mitochondria with NMF and NADPH did not lead to raised levels of lipid peroxides. The effects described were specific to NMF as incubation of N,N-dimethylformamide, N-hydroxymethylformamide or formamide with hepatocytes did not result in glutathione depletion or increased lipid peroxidation. NMF undergoes extensive metabolism in vivo and the results indicate that NMF forms a chemically reactive metabolite, even though incubation of the drug with liver fractions or hepatocytes did not lead to metabolites at levels which were analytically identifiable.
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29
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Stromberg PC, Vogtsberger LM, Marsh LR. Pathology of the mononuclear cell leukemia of Fischer rats. III. Clinical chemistry. Vet Pathol 1983; 20:718-26. [PMID: 6649340 DOI: 10.1177/030098588302000607] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Serum biochemical analyses were done on F344 rats in the early and late stages of mononuclear cell leukemia. There were marked increases in serum bilirubin, alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and alkaline phosphatase. Increases in these parameters generally were more severe in the late stages of leukemia. Both direct and indirect-reacting bilirubin were increased with the unconjugated form predominating early and the conjugated form predominating late in the course of the disease. Lactate dehydrogenase isoenzyme determination correlated with histological examination indicated that liver damage was responsible for the observed changes. Urinalysis revealed marked hemoglobinuria, bilirubinuria and increased urine urobilinogen. Serum protein electrophoresis revealed marked reductions in the alpha globulin fractions.
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30
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Brondeau MT, Bonnet P, Guenier JP, De Ceaurriz J. Short-term inhalation test for evaluating industrial hepatotoxicants in rats. Toxicol Lett 1983; 19:139-46. [PMID: 6658818 DOI: 10.1016/0378-4274(83)90274-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Liver damage was investigated in rat using serum enzyme activities measurements. Responses were recorded 24 h after whole body inhalation exposure to vapors of bromobenzene, carbon tetrachloride, chloroform, o-dichlorobenzene, 1,2-dichloroethane and dimethylformamide as model toxicants. First, rats were exposed during a single 4 h period to different concentrations of each solvent and the minimally active concentration was determined. Second, repeated exposures to chemicals at this concentration level (6 h daily, 2 or 4 days) were used in order to examine whether hepatotoxicity was enhanced. GLDH and SDH are more sensitive and more constant indices than GOT and GPT. It appears that a single exposure period induced more marked serum activities enhancement than repeated exposures.
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31
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Hewitt WR, Brown EM, Plaa GL. Relationship between the carbon skeleton length of ketonic solvents and potentiation of chloroform-induced hepatotoxicity in rats. Toxicol Lett 1983; 16:297-304. [PMID: 6857725 DOI: 10.1016/0378-4274(83)90190-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Previous studies have suggested that ketonic solvents potentiate the hepatotoxic action of CHCl3 in rats. In addition, the relative potentiating capacity of the ketones appeared to be related to the length of their carbon skeleton. To test this hypothesis CHCl3-induced liver injury was evaluated in male Sprague-Dawley rats pretreated (15 mmol/kg, p.o.) with acetone (Ac), 2-butanone (Bu), 2-pentanone (Pn), 2-hexanone (Hx) or 2-heptanone (Hp). After 18 h, a challenging dose of CHCl3, (0.50 or 0.75 ml/kg, i.p.) was given. Liver damage was evaluated 24 h after CHCl3 administration by determining elevations in plasma GPT and OCT activity. Neither Ac, Bu, Pn, Hx, Hp or the CHCl3 challenging dosages produced marked liver injury when given alone. However, each of the ketones potentiated CHCl3-induced liver damage. The severity of the potentiated hepatotoxic response was significantly (positively) correlated with the ketone carbon chain length. These observations suggest that carbon skeleton length may play a role in determining the relative potentiating capacity of ketonic solvents.
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Abstract
The acute hepato- and nephrotoxic potentials of two trihalomethane water contaminants, bromodichloromethane (BrCHCl2) and dibromochloromethane (Br2CHCl), were determined in male Sprague-Dawley rats. Br2CHCl possessed a greater hepatotoxic and lethal potential than BrCHCl2. However, both Br2CHCl and BrCHCl2 were weak hepatotoxicants as compared to a related trihalomethane, CHCl3. Br2CHCl and BrCHCl2 did not produce liver injury until near-lethal dosages were administered. Neither trihalomethane appeared to produce appreciable kidney injury during the 24-h challenge period. Pretreatment of rats with acetone (15 mmol/kg, p.o.) markedly potentiated the hepatotoxic response to BrCHCl2 and Br2CHCl. The potentiated response observed with acetone plus BrCHCl2 or Br2CHCl was equal to or greater than that observed with acetone plus an approximately equimolar dosage of CHCl3. That is, acetone appeared to convert these weak hepatotoxicants into strong hepatotoxicants.
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33
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Story DL, Gee SJ, Tyson CA, Gould DH. Response of isolated hepatocytes to organic and inorganic cytotoxins. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 1983; 11:483-501. [PMID: 6620399 DOI: 10.1080/15287398309530362] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Thirty-four chemicals-diverse in structure, postulated mechanisms of action, and primary target organs--were tested for cytotoxic response in isolated hepatocyte suspensions from young male Sprague-Dawley rats. Hepatocytes were incubated in the presence and absence of the test chemicals in closed vessels fitted with side arms for serial sampling for up to 5 h at 37 degrees C with gentle shaking under an O2:CO2 (95:5) atmosphere. The parameters evaluated were glutamate-oxaloacetate transaminase and lactate dehydrogenase release from the cells, Trypan blue exclusion, cell count, urea synthesis capability, and steady-state ATP levels. All chemicals cytotoxic in animals following single or short-term repeated exposures caused statistically significant changes in one or more of these parameters in the 0.01-10-mM concentration range. Dimethylnitrosamine and thioacetamide were not as potent in the isolated cell system as expected from their in vivo hepatotoxicity, and the quantitative changes produced with thioacetamide in the hepatocytes were marginal, even at 10 mM. The solvents tested--ethanol, acetone, dimethyl sulfoxide (DMSO), and propylene glycol--were without effect. These results indicate that isolated hepatocyte suspensions are useful for the identification of cytotoxins in general and hepatotoxins in particular, but that their capability for yielding a quantitative index of cytotoxic potential for diverse chemical species remains to be demonstrated.
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Hétu C, Dumont A, Joly JG. Effect of chronic ethanol administration on bromobenzene liver toxicity in the rat. Toxicol Appl Pharmacol 1983; 67:166-77. [PMID: 6836572 DOI: 10.1016/0041-008x(83)90221-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Female Sprague-Dawley rats were pair-fed a nutritionally adequate liquid diet containing either ethanol or isocaloric carbohydrate for 3 weeks. In vitro studies showed that chronic ethanol pretreatment preferentially increased the liver microsomal biotransformation of bromobenzene to p-bromophenol (via the toxic 3,4-epoxide) rather than to o-bromophenol (via the nontoxic 2,3-epoxide) and could thus potentiate bromobenzene hepatotoxicity. Bromobenzene administration (500 mg/kg body weight, ip), after an overnight fast, was associated in ethanol-pretreated rats with greater and accelerated liver glutathione depletion and subsequent decrease in liver cytochrome P-450 content than in controls. As assessed histologically and by determination of the rise in activities of serum enzyme markers of liver necrosis, chronic ethanol pretreatment, however, mainly resulted in earlier onset and resolution of bromobenzene-induced liver necrosis, with only a mild increase in the maximal severity of liver lesions. These results suggest that the twofold increase in liver microsomal bromobenzene 3,4-epoxidation by ethanol, being much less than that seen after phenobarbital pretreatment in our animal model and in that of others, is apparently not sufficient to markedly affect the severity of bromobenzene-induced liver toxicity.
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Plaa GL, Hewitt WR, du Souich P, Caillé G, Lock S. Isopropanol and acetone potentiation of carbon tetrachloride-induced hepatotoxicity: single versus repetitive pretreatments in rats. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 1982; 9:235-50. [PMID: 6281449 DOI: 10.1080/15287398209530158] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Acute oral pretreatment of rats with isopropanol or acetone results in a dose-related potentiation of CCl4 hepatotoxicity. Minimally effective doses (MED) and noneffective doses (NED) of both agents were estimated to be 0.25 and 0.10 ml/kg, respectively. Six MED given twice a day over 3 d caused a greater potentiation than a single MED, but not as much as that produced by the total dose given singly. Six NED given over 3 d did not potentiate CCl4, whereas the total dose did when given singly. A threshold for isopropanol and acetone appears to exist in the rat. A total dose of 1.5 ml/kg acetone was administered by four different treatment regimens (bolus, divided doses, infusion) over 3 d. Potentiation of CCl4 hepatotoxicity was then correlated with blood pharmacokinetic parameters: area under the concentration-time curve and peak blood concentration. An excellent correlation was found between the degree of potentiation observed and the peak blood concentration attained, but no correlation was found with area under the curve. Results of iv acetone infusions (over 3 d) with higher doses support the hypothesis that a threshold concentration of acetone is critical in the potentiation of CCl4 hepatotoxicity in the rat.
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Abstract
Dimethylformamide (DMF) and its biotransformation products monomethylformamide (MMF) and formamide (F) were administered intraperitoneally to rats. Serum levels of sorbitol dehydrogenase (SDH) were studied at 3 h intervals from 9 h to 30 h after administration. Liver histology at 12, 21 and 30 h proved elevated SDH levels to be an indication of liver necrosis. DMF 479 mg/kg produced elevated enzyme levels at 27 h and 30 h while half the dose, 240 mg/kg, produced elevated levels from 15 h onwards. MMF 387 mg/kg produced elevated SDH levels at all times studied. F did not give elevated levels at any time. DMF (479 mg/kg) and MMF (387 mg/kg) administered simultaneously produced elevated SDH levels from 24 h onwards. These findings suggest that DMF hepatotoxicity is mediated by a degradation product of MMF and that DMF delays the hepatotoxic effect induced by MMF.
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Summer KH, Greim H. Detoxification of chloroprene (2-chloro-1,3-butadiene) with glutathione in the rat. Biochem Biophys Res Commun 1980; 96:566-73. [PMID: 7425999 DOI: 10.1016/0006-291x(80)91393-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Hewitt WR, Miyajima H, Côté MG, Plaa GL. Acute alteration of chloroform-induced hepato- and nephrotoxicity by n-hexane, methyl n-butyl ketone, and 2,5-hexanedione. Toxicol Appl Pharmacol 1980; 53:230-48. [PMID: 7394766 DOI: 10.1016/0041-008x(80)90423-8] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Plugge H, Jaeger RJ. Acute inhalation toxicity of 2-chloro-1,3-butadiene (chloroprene): effects on liver and lung. Toxicol Appl Pharmacol 1979; 50:565-72. [PMID: 117569 DOI: 10.1016/0041-008x(79)90411-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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40
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Hewitt WR, Miyajima H, Côté MG, Plaa GL. Acute alteration of chloroform-induced hepato- and nephrotoxicity by Mirex and Kepone. Toxicol Appl Pharmacol 1979; 48:509-27. [PMID: 89712 DOI: 10.1016/0041-008x(79)90434-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Hewitt WR, Plaa GL. Potentiation of carbon tetrachloride-induced hepatotoxicity by 1,3-butanediol. Toxicol Appl Pharmacol 1979; 47:177-80. [PMID: 425116 DOI: 10.1016/0041-008x(79)90084-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Clampitt RB, Hart RJ. The tissue activities of some diagnostic enzymes in ten mammalian species. J Comp Pathol 1978; 88:607-21. [PMID: 30785 DOI: 10.1016/0021-9975(78)90014-2] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Abstract
Rats were dosed with CCl4 or diethylamine to induce liver injury. The time and magnitude of peak liver injury were assessed by histopathological examination of liver specimens taken at intervals after dosing. Serum enzymes were measured at the same intervals. Serum ornithine carbamyl transferase (SOCT) activity increased at least 6-fold in animals that showed liver damage by histopathology, and fell again as the injuries resolved. Measurements of other enzymes were less sensitive. SOCT measurements appear to be as sensitive a method as histopathology for detecting liver damage caused by administering xenobiotics. Since serum enzyme measurements do not require that the animals be sacrificed, they can be used for repeated examinations of the same animals, thus increasing the likelihood of detecting transient injury.
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Korsrud GO, Kuiper-Goodman T, Hasselager E, Grice HC, McLaughlan JM. Effects of dietary protein level on carbon tetrachloride-induced liver damage in rats. Toxicol Appl Pharmacol 1976; 37:1-12. [PMID: 968902 DOI: 10.1016/s0041-008x(76)80002-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Drotman RB. A study of kinetic parameters for the use of serum ornithine carbamoyltransferase as an index of liver damage. FOOD AND COSMETICS TOXICOLOGY 1975; 13:649-51. [PMID: 1205439 DOI: 10.1016/0015-6264(75)90155-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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46
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Jaeger RJ, Conolly RB, Murphy SD. Short-term inhalation toxicity of halogenated hydrocarbons: effects on fasting rats. ARCHIVES OF ENVIRONMENTAL HEALTH 1975; 30:26-31. [PMID: 1109268 DOI: 10.1080/00039896.1975.10666628] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Male rats, fasted overnight (18 hours), and exposed to various materials in inhalation were more sensitive to the hepatotoxic effects of carbon tetrachloride, 2-chlorobutadiene, 1,1-dibromoethylene, and 1,1-dichloroethylene (DCE). Vinyl chloride monomer and 1,1-difluoroethylene were not acutely hepatotoxic in fed or fasted rats at any concentration tested. Vinyl chloride monomer when administered simultaneously with DCE prevented the injury associated with DCE inhalation in fasted rats. This prevention of injury may be a result of a competitive interaction since the effect was concentration dependent.
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Korsrud GO, Trick KD. Activities of several enzymes in serum and heparinized plasma from rats. Clin Chim Acta 1973; 48:311-5. [PMID: 4765711 DOI: 10.1016/0009-8981(73)90201-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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