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Liu M, Liu Y, Wang X. Discrimination between the Triglyceride Form and the Ethyl Ester Form of Fish Oil Using Chromatography-Mass Spectrometry. Foods 2024; 13:1128. [PMID: 38611433 PMCID: PMC11012042 DOI: 10.3390/foods13071128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 03/25/2024] [Accepted: 03/30/2024] [Indexed: 04/14/2024] Open
Abstract
Although the triglyceride form is the natural form of fish oil found in fish, the ethyl ester form of fish oil, which is used during processing to save costs, is also present on the market. In this study, fatty acids and lipids were determined using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-linear ion trap mass spectrometry (LC-LIT/MS), respectively, according to developed methods. The identification of fatty acids was based on the mass spectral characteristics and equivalent chain lengths. However, the fatty acid contents of both forms of fish oils are quite similar. The application of the LC-LIT/MS method for the structural characterization of triacylglycerols (TAGs) and the mechanism of LIT/MS fragmentation are also discussed. Neutral losses of CH2=CH2 (m/z 28) and CH3CH2OH (m/z 46), which are LIT/MS characteristics of ethyl ester from fish oil, were found for the first time. The triglyceride form of fish oils was easily and accurately identified using fingerprint chromatography. In conclusion, lipid analysis combined with LC-LIT/MS showed an improved capability to distinguish between types of fish oil.
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Affiliation(s)
- Mingxuan Liu
- Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan 430062, China; (M.L.); (Y.L.)
- College of Chemistry, Beijing University of Chemical Technology, Beijing 100029, China
| | - Yuchong Liu
- Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan 430062, China; (M.L.); (Y.L.)
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan 430062, China
- Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture, Wuhan 430062, China
- Laboratory of Risk Assessment for Oilseeds Products (Wuhan), Ministry of Agriculture, Wuhan 430062, China
- Quality Inspection and Test Center for Oilseeds Products, Ministry of Agriculture, Wuhan 430062, China
| | - Xiupin Wang
- Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan 430062, China; (M.L.); (Y.L.)
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, Wuhan 430062, China
- Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture, Wuhan 430062, China
- Laboratory of Risk Assessment for Oilseeds Products (Wuhan), Ministry of Agriculture, Wuhan 430062, China
- Quality Inspection and Test Center for Oilseeds Products, Ministry of Agriculture, Wuhan 430062, China
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2
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Ombredane AS, Silva LRA, Araujo VHS, Costa PL, Silva LC, Sampaio MC, Lima MCF, Veiga Junior VF, Vieira IJC, Azevedo RB, Joanitti GA. Pequi oil (Caryocar brasilense Cambess.) nanoemulsion alters cell proliferation and damages key organelles in triple-negative breast cancer cells in vitro. Biomed Pharmacother 2022; 153:113348. [PMID: 35820315 DOI: 10.1016/j.biopha.2022.113348] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/24/2022] [Accepted: 06/24/2022] [Indexed: 11/28/2022] Open
Abstract
Pequi oil is extracted from the fruit of a Brazilian native plant (Caryocar brasiliense Camb) that contains some molecules with anticancer potential. Due to its hydrophobic property, the administration of pequi oil associated with nanoemulsion systems represents a successful strategy to improve oil bioavailability. Breast cancer is the most frequent type of cancer among women and conventional therapies used are frequently associated with several side effects. Thus, the aim of this study was to investigate the effects of pequi oil-based nanoemulsion (PeNE) on triple-negative breast cancer cells (4T1), in vitro. PeNE presented a dose- and time-dependent cytotoxic effect with lower IC50 than free pequi oil after 48 h of exposure (p < 0.001). At 180 µg/mL, PeNE demonstrated numerous cell alterations, when compared to free pequi oil, such as morphological alterations, reduction in cell proliferation and total cell number, damage to plasmatic membrane, induction of lysosomal membrane permeability and depolarization of mitochondrial membrane, alteration of intracellular ROS production and calcium level, and increase in phosphatidylserine exposure. Taken together, the results suggest an interesting induction of cell death mechanisms involving a combined action of factors that impair nucleus, mitochondria, lysosome, and ER function. In addition, more pronounced effects were observed in cells treated by PeNE at 180 µg/mL when compared to free pequi oil, thereby reinforcing the advantages of using nanometric platforms. These promising results highlight the use of PeNE as a potential complementary therapeutic approach to be employed along with conventional treatments against breast cancer in the future.
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Affiliation(s)
- Alicia S Ombredane
- Laboratory of Bioactive Compounds and Nanobiotechnology (LBCNano), University of Brasilia, Campus Universitário - Centro Metropolitano, Ceilândia Sul, Brasília, DF 72220-275, Brazil; Post-Graduation Program in Nanoscience and Nanobiotechnology, Institute of Biological Sciences, University of Brasilia, Campus Universitário Darcy Ribeiro, Brasília 70910-900, Brazil
| | - Lídia R A Silva
- Laboratory of Bioactive Compounds and Nanobiotechnology (LBCNano), University of Brasilia, Campus Universitário - Centro Metropolitano, Ceilândia Sul, Brasília, DF 72220-275, Brazil
| | - Victor H S Araujo
- Laboratory of Bioactive Compounds and Nanobiotechnology (LBCNano), University of Brasilia, Campus Universitário - Centro Metropolitano, Ceilândia Sul, Brasília, DF 72220-275, Brazil
| | - Patrícia L Costa
- Laboratory of Bioactive Compounds and Nanobiotechnology (LBCNano), University of Brasilia, Campus Universitário - Centro Metropolitano, Ceilândia Sul, Brasília, DF 72220-275, Brazil; Post-Graduation Program in Sciences and Technologies in Health, Faculty of Ceilandia, University of Brasilia, Campus Universitário - Centro Metropolitano, Ceilândia Sul, Brasília, DF 72220-275, Brazil
| | - Lucas C Silva
- Laboratory of Bioactive Compounds and Nanobiotechnology (LBCNano), University of Brasilia, Campus Universitário - Centro Metropolitano, Ceilândia Sul, Brasília, DF 72220-275, Brazil; Post-Graduation Program in Sciences and Technologies in Health, Faculty of Ceilandia, University of Brasilia, Campus Universitário - Centro Metropolitano, Ceilândia Sul, Brasília, DF 72220-275, Brazil
| | - Marina C Sampaio
- Laboratory of Bioactive Compounds and Nanobiotechnology (LBCNano), University of Brasilia, Campus Universitário - Centro Metropolitano, Ceilândia Sul, Brasília, DF 72220-275, Brazil; Post-Graduation Program in Nanoscience and Nanobiotechnology, Institute of Biological Sciences, University of Brasilia, Campus Universitário Darcy Ribeiro, Brasília 70910-900, Brazil
| | - Milena C F Lima
- Chemistry Section, Military Institute of Engineering, Praça Gen. Tibúrcio, 80, Praia Vermelha, Rio de Janeiro, RJ 22290-270, Brazil
| | - Valdir F Veiga Junior
- Chemistry Section, Military Institute of Engineering, Praça Gen. Tibúrcio, 80, Praia Vermelha, Rio de Janeiro, RJ 22290-270, Brazil
| | - Ivo J C Vieira
- Laboratório de Ciências Químicas-LCQUI, Universidade Estadual do Norte Fluminense Darcy Ribeiro-UENF, Avenida Alberto Lamego 2000, Campos dos Goytacazes, RJ 28013-602, Brazil
| | - Ricardo B Azevedo
- Post-Graduation Program in Nanoscience and Nanobiotechnology, Institute of Biological Sciences, University of Brasilia, Campus Universitário Darcy Ribeiro, Brasília 70910-900, Brazil; Laboratory of Nanobiotechnology, Institute of Biological Sciences, Department of Genetics and Morphology, University of Brasilia, Campus Universitário Darcy Ribeiro, Brasília 70910-900, Brazil
| | - Graziella A Joanitti
- Laboratory of Bioactive Compounds and Nanobiotechnology (LBCNano), University of Brasilia, Campus Universitário - Centro Metropolitano, Ceilândia Sul, Brasília, DF 72220-275, Brazil; Post-Graduation Program in Nanoscience and Nanobiotechnology, Institute of Biological Sciences, University of Brasilia, Campus Universitário Darcy Ribeiro, Brasília 70910-900, Brazil; Post-Graduation Program in Sciences and Technologies in Health, Faculty of Ceilandia, University of Brasilia, Campus Universitário - Centro Metropolitano, Ceilândia Sul, Brasília, DF 72220-275, Brazil.
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3
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Kapur BM, Baber M. FASD: folic acid and formic acid — an unholy alliance in the alcohol abusing mother. Biochem Cell Biol 2018; 96:189-197. [DOI: 10.1139/bcb-2017-0079] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Alcohol consumption during pregnancy remains a significant cause of preventable birth defects and developmental disabilities; however, the mechanism of toxicity remains unclear. Methanol is present as a congener in many alcoholic beverages and is formed endogenously. Because ethanol is preferentially metabolized over methanol, it has been found in the sera and cerebro-spinal fluid of alcoholics. Toxicity resulting from methanol has been attributed to formic acid. Formic acid is present in significantly higher quantities in the biofluids of alcoholics. These higher levels can be cytotoxic and cause neuronal cell death. However, the adverse effects can be mitigated by adequate levels of hepatic folic acid, because formic acid elimination depends on folic acid. During pregnancy, folate concentrations are at least 2-fold higher in cord blood then in maternal blood, owing to increased folate requirements. The reverse has been demonstrated in pregnancies with alcohol abuse, suggesting downregulation of folate transporters and low fetal folate levels. Moreover, formic acid can cross the placenta and its adverse effects can be mitigated by folic acid. Thus, the combination of low fetal folate levels and presence of formic acid form a potent cytotoxic combination that may play a significant role in the etiology of fetal alcohol spectrum disorder.
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Affiliation(s)
- Bhushan M. Kapur
- Department of Clinical Pathology, Sunnybrook Health Science Centre, 2075 Bayview Avenue, Toronto, ON M4N 3M5; Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Marta Baber
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
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Heier C, Xie H, Zimmermann R. Nonoxidative ethanol metabolism in humans-from biomarkers to bioactive lipids. IUBMB Life 2016; 68:916-923. [PMID: 27714979 PMCID: PMC5324703 DOI: 10.1002/iub.1569] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 09/19/2016] [Indexed: 12/21/2022]
Abstract
Ethanol is a widely used psychoactive drug whose chronic abuse is associated with organ dysfunction and disease. Although the prevalent metabolic fate of ethanol in the human body is oxidation a smaller fraction undergoes nonoxidative metabolism yielding ethyl glucuronide, ethyl sulfate, phosphatidylethanol and fatty acid ethyl esters. Nonoxidative ethanol metabolites persist in tissues and body fluids for much longer than ethanol itself and represent biomarkers for the assessment of ethanol intake in clinical and forensic settings. Of note, the nonoxidative reaction of ethanol with phospholipids and fatty acids yields bioactive compounds that affect cellular signaling pathways and organelle function and may contribute to ethanol toxicity. Thus, despite low quantitative contributions of nonoxidative pathways to overall ethanol metabolism the resultant ethanol metabolites have important biological implications. In this review we summarize the current knowledge about the enzymatic formation of nonoxidative ethanol metabolites in humans and discuss the implications of nonoxidative ethanol metabolites as biomarkers of ethanol intake and mediators of ethanol toxicity. © 2016 IUBMB Life, 68(12):916-923, 2016.
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Affiliation(s)
- Christoph Heier
- Institute of Molecular Biosciences, University of GrazAustria
| | - Hao Xie
- Institute of Molecular Biosciences, University of GrazAustria
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5
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Heier C, Taschler U, Radulovic M, Aschauer P, Eichmann TO, Grond S, Wolinski H, Oberer M, Zechner R, Kohlwein SD, Zimmermann R. Monoacylglycerol Lipases Act as Evolutionarily Conserved Regulators of Non-oxidative Ethanol Metabolism. J Biol Chem 2016; 291:11865-75. [PMID: 27036938 PMCID: PMC4882453 DOI: 10.1074/jbc.m115.705541] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Indexed: 12/27/2022] Open
Abstract
Fatty acid ethyl esters (FAEEs) are non-oxidative metabolites of ethanol that accumulate in human tissues upon ethanol intake. Although FAEEs are considered as toxic metabolites causing cellular dysfunction and tissue damage, the enzymology of FAEE metabolism remains poorly understood. In this study, we used a biochemical screen in Saccharomyces cerevisiae to identify and characterize putative hydrolases involved in FAEE catabolism. We found that Yju3p, the functional orthologue of mammalian monoacylglycerol lipase (MGL), contributes >90% of cellular FAEE hydrolase activity, and its loss leads to the accumulation of FAEE. Heterologous expression of mammalian MGL in yju3Δ mutants restored cellular FAEE hydrolase activity and FAEE catabolism. Moreover, overexpression or pharmacological inhibition of MGL in mouse AML-12 hepatocytes decreased or increased FAEE levels, respectively. FAEEs were transiently incorporated into lipid droplets (LDs) and both Yju3p and MGL co-localized with these organelles. We conclude that the storage of FAEE in inert LDs and their mobilization by LD-resident FAEE hydrolases facilitate a controlled metabolism of these potentially toxic lipid metabolites.
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Affiliation(s)
- Christoph Heier
- From the Institute of Molecular Biosciences, University of Graz and
| | - Ulrike Taschler
- From the Institute of Molecular Biosciences, University of Graz and
| | - Maja Radulovic
- From the Institute of Molecular Biosciences, University of Graz and
| | - Philip Aschauer
- From the Institute of Molecular Biosciences, University of Graz and
| | | | - Susanne Grond
- From the Institute of Molecular Biosciences, University of Graz and
| | - Heimo Wolinski
- From the Institute of Molecular Biosciences, University of Graz and BioTechMed-Graz, 8010 Graz, Austria
| | - Monika Oberer
- From the Institute of Molecular Biosciences, University of Graz and
| | - Rudolf Zechner
- From the Institute of Molecular Biosciences, University of Graz and
| | - Sepp D Kohlwein
- From the Institute of Molecular Biosciences, University of Graz and BioTechMed-Graz, 8010 Graz, Austria
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6
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Bearer CF. A short history of fatty acid ethyl esters. Alcohol Clin Exp Res 2015; 39:413-5. [PMID: 25706667 DOI: 10.1111/acer.12675] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Accepted: 01/12/2015] [Indexed: 11/29/2022]
Affiliation(s)
- Cynthia F Bearer
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland
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7
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Zelner I, Matlow JN, Natekar A, Koren G. Synthesis of fatty acid ethyl esters in mammalian tissues after ethanol exposure: a systematic review of the literature. Drug Metab Rev 2013; 45:277-99. [PMID: 23713893 DOI: 10.3109/03602532.2013.795584] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The ability to undergo non-oxidative metabolism from ethanol to fatty acid ethyl esters (FAEEs) varies greatly among tissues and organs. To gain a greater understanding of non-oxidative ethanol metabolism to FAEE, we aimed to collect all published data on FAEE synthesis in mammalian organs and tissues to identify all tissues, organs, and enzymes that are known to, or likely possess FAEE-synthetic activity. A systematic search for relevant papers was performed and two independent reviewers examined potentially relevant abstracts (articles on FAEEs that pertain to ethanol exposure) to determine whether they met the inclusion criteria. Information on FAEE synthesis was retrieved from papers meeting the inclusion/exclusion criteria and summarized by organ/tissue/matrix examined. The systematic search through four databases yielded 78 articles that investigated FAEE synthesis by tissues, tissue fractions and cell lines, and 29 articles that attempted to purify and/or characterize the enzymes involved in FAEE synthesis. Two enzyme activities have been studied: FAEE synthase (FAEES, which conjugates ethanol and free fatty acid) and acyl-CoA: ethanol O-acyltransferase (AEAT, which conjugates ethanol and fatty acyl-CoA). Both activities are expressed by a variety of different enzymes. FAEES activity is the most widely studied and has been purified from several tissues and shown to be associated with several well-known enzymes, while the identity of enzymes possessing AEAT activity remains unknown. The organs and tissues that have been shown to synthesize FAEEs are discussed, with special emphasis on the studies that attempted to elucidate the enzymology of FAEE synthesis in those tissues.
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Affiliation(s)
- Irene Zelner
- Division of Clinical Pharmacology and Toxicology, Hospital for Sick Children, Toronto, Ontario, Canada
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8
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Elamin E, Masclee A, Juuti-Uusitalo K, van IJzendoorn S, Troost F, Pieters HJ, Dekker J, Jonkers D. Fatty acid ethyl esters induce intestinal epithelial barrier dysfunction via a reactive oxygen species-dependent mechanism in a three-dimensional cell culture model. PLoS One 2013; 8:e58561. [PMID: 23526996 PMCID: PMC3602318 DOI: 10.1371/journal.pone.0058561] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 02/05/2013] [Indexed: 12/15/2022] Open
Abstract
Background & Aims Evidence is accumulating that ethanol and its oxidative metabolite, acetaldehyde, can disrupt intestinal epithelial integrity, an important factor contributing to ethanol-induced liver injury. However, ethanol can also be metabolized non-oxidatively generating phosphatidylethanol and fatty acid ethyl esters (FAEEs). This study aims to investigate the effects of FAEEs on barrier function, and to explore the role of oxidative stress as possible mechanism. Methods Epithelial permeability was assessed by paracellular flux of fluorescein isothiocyanate-conjugated dextran using live cell imaging. Cell integrity was evaluated by lactate dehydrogenase release. Localization and protein levels of ZO-1 and occludin were analyzed by immunofluorescence and cell-based ELISA, respectively. Intracellular oxidative stress and cellular ATP levels were measured by dichlorofluorescein and luciferase driven bioluminescence, respectively. Results In vitro, ethyl oleate and ethyl palmitate dose dependently increased permeability associated with disruption and decreased ZO-1 and occludin protein levels, respectively, and increased intracellular oxidative stress without compromising cell viability. These effects could partially be attenuated by pretreatment with the antioxidant, resveratrol, pointing to the role of oxidative stress in the FAEEs-induced intestinal barrier dysfunction. Conclusions These findings show that FAEEs can induce intestinal barrier dysfunction by disrupting the tight junctions, most likely via reactive oxygen species-dependent mechanism.
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Affiliation(s)
- Elhaseen Elamin
- Top Institute Food and Nutrition (TIFN), Wageningen, The Netherlands
- Department of Internal Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Ad Masclee
- Top Institute Food and Nutrition (TIFN), Wageningen, The Netherlands
- Department of Internal Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Kati Juuti-Uusitalo
- Top Institute Food and Nutrition (TIFN), Wageningen, The Netherlands
- Institute of Biomedical Technology, University of Tampere, Tampere, Finland
| | - Sven van IJzendoorn
- Top Institute Food and Nutrition (TIFN), Wageningen, The Netherlands
- Department of Cell Biology, University Medical Center Groningen, Groningen, The Netherlands
| | - Freddy Troost
- Top Institute Food and Nutrition (TIFN), Wageningen, The Netherlands
- Department of Internal Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Harm-Jan Pieters
- Department of Internal Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Jan Dekker
- Top Institute Food and Nutrition (TIFN), Wageningen, The Netherlands
- Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands
| | - Daisy Jonkers
- Top Institute Food and Nutrition (TIFN), Wageningen, The Netherlands
- Department of Internal Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
- * E-mail:
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9
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K Bhopale K, Nauduri D, V Soman K, K Sood G, Okorodudu A, Ansari GAS, S Kaphalia B. Differentially Altered Plasma Proteins in
Patients diagnosed with Alcoholic and
Nonalcoholic Fatty Liver Disease. Euroasian J Hepatogastroenterol 2011. [DOI: 10.5005/jp-journals-10018-1019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
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10
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Röttig A, Wenning L, Bröker D, Steinbüchel A. Fatty acid alkyl esters: perspectives for production of alternative biofuels. Appl Microbiol Biotechnol 2009; 85:1713-33. [DOI: 10.1007/s00253-009-2383-z] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2009] [Revised: 11/23/2009] [Accepted: 11/24/2009] [Indexed: 12/01/2022]
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Syn WK, Teaberry V, Choi SS, Diehl AM. Similarities and differences in the pathogenesis of alcoholic and nonalcoholic steatohepatitis. Semin Liver Dis 2009; 29:200-10. [PMID: 19387919 PMCID: PMC3644873 DOI: 10.1055/s-0029-1214375] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Subpopulations of individuals with alcohol-induced fatty livers and nonalcoholic steatosis develop steatohepatitis. Steatohepatitis is defined histologically: increased numbers of injured and dying hepatocytes distinguish this condition from simple steatosis. The increased hepatocyte death is generally accompanied by hepatic accumulation of inflammatory cells and sometimes increases in myofibroblastic cells, leading to hepatic fibrosis and eventually, cirrhosis. The purpose of this review is to summarize similarities and differences in the pathogenesis of steatohepatitis in alcoholic fatty liver disease and nonalcoholic fatty liver disease.
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Affiliation(s)
- Wing-Kin Syn
- Division of Gastroenterology, Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - Vanessa Teaberry
- Department of Surgery, Duke University Medical Center, Durham, North Carolina
| | - Steve S. Choi
- Division of Gastroenterology, Department of Medicine, Duke University Medical Center, Durham, NC 27710,Section of Gastroenterology, Department of Medicine, Durham Veteran Affairs Medical Center, Durham, NC 27705
| | - Anna Mae Diehl
- Division of Gastroenterology, Department of Medicine, Duke University Medical Center, Durham, NC 27710
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12
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Alhomsi K, Selig M, Sustic T, Katrangi E, Weissig V, Laposata M. Induction of Apoptosis and Necrosis in Human Peripheral Blood Mononuclear Cells by Fatty Acid Ethyl Esters. Alcohol Clin Exp Res 2008; 32:534-43. [DOI: 10.1111/j.1530-0277.2007.00597.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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13
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Castaneda F, Zimmermann D, Nolte J, Baumbach JI. Role of undecan-2-one on ethanol-induced apoptosis in HepG2 cells. Cell Biol Toxicol 2007; 23:477-85. [PMID: 17453350 DOI: 10.1007/s10565-007-9009-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2006] [Accepted: 03/16/2007] [Indexed: 12/20/2022]
Abstract
Based on the reduced expression of ethanol-oxidizing enzymes in human hepatocellular carcinoma (HepG2) cells, we analyzed the role of nonoxidative metabolites in ethanol-induced apoptosis in HepG2 cells. For this purpose, an analysis of volatile metabolites of ethanol using ion-mobility spectrometry and gas chromatography-mass spectrometry was performed. HepG2 cells exposed to 1 mmol/L ethanol exhibited significant synthesis of undecan-2-one compared to untreated cells. Undecan-2-one is a fatty acid ethyl ester metabolite synthesized through a nonoxidative pathway. Undecan-2-one had a dose-dependent cytotoxic effect on HepG2 cells as shown by release of lactate dehydrogenase (LDH). The most notable finding of this study was the potentiation of ethanol-induced apoptosis demonstrated by an increased apoptotic rate induced by undecan-2-one in ethanol-treated HepG2 cells. The data presented in this study contribute to the better understanding of the molecular mechanisms of ethanol exposure at low concentration in HepG2 cells, a human hepatocellular carcinoma-derived cell line.
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Affiliation(s)
- F Castaneda
- Laboratory for Molecular Pathobiochemistry and Clinical Research, Max Planck Institute for Molecular Physiology, Dortmund, Germany.
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14
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Borucki K, Dierkes J, Wartberg J, Westphal S, Genz A, Luley C. In Heavy Drinkers, Fatty Acid Ethyl Esters Remain Elevated for Up to 99 Hours. Alcohol Clin Exp Res 2007; 31:423-7. [PMID: 17295726 DOI: 10.1111/j.1530-0277.2006.00323.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Both medical and forensic needs require reliable detection of earlier ethanol intake after the disappearance of ethanol from blood. The esters of ethanol with free fatty acids (FAEEs) are candidate markers of this kind. However, it is unknown whether FAEEs can serve as a marker for a single prior ethanol intake. In addition, the period for which FAEEs are elevated is unknown. Therefore, we measured FAEEs in heavy drinkers admitted to detoxification, and in healthy subjects after a drinking experiment. METHODS Blood from 30 heavy drinkers was obtained for up to 5 days during a detoxification period in a psychiatric hospital. In addition, 17 healthy subjects who participated in a drinking experiment and who were abstinent thereafter gave blood during a similar time period for analysis of FAEEs. Fatty acid ethyl esters were measured by gas chromatography-mass spectroscopy. RESULTS Heavy drinkers had much higher ethanol and FAEEs concentrations than healthy subjects; however, in both groups, FAEEs decreased rapidly during the first day. Only in heavy drinkers, elevated concentrations of FAEEs were observed at days 2 to 4. Concentrations of FAEEs were not associated with serum triglycerides or patients' body mass index. CONCLUSIONS It is concluded that kinetics of FAEEs are different in heavy drinkers compared with healthy subjects and that FAEEs are of limited value for the detection of prior single ethanol intake.
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Affiliation(s)
- K Borucki
- Institute of Clinical Chemistry and Biochemistry, Magdeburg University Hospital, Germany.
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15
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Salem RO, Laposata M. Activation and impairment of platelet function in vitro by fatty acid ethyl ester, a nonoxidative ethanol metabolite: effect of fatty acid ethyl esters on human platelets. Alcohol Clin Exp Res 2007; 30:2079-88. [PMID: 17117973 DOI: 10.1111/j.1530-0277.2006.00256.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND The goal of this study was to investigate the effect of fatty acid ethyl esters (FAEE), nonoxidative metabolites of ethanol, on platelet function. We hypothesized that FAEE increase the risk of bleeding by producing an alteration in platelet membrane structure or function. METHODS Isolated human platelets incubated with FAEE were prepared and multiple assays for platelet activation were performed; beta-thromboglobulin release from platelet granules, platelet aggregation, arachidonate release from phospholipids, and intracellular cyclic AMP (cAMP) levels. We examined also the combined effect of epinephrine and FAEE on platelet aggregation. RESULTS FAEE induced platelet shape change, release of alpha granules and release of arachidonate from phospholipids without an increase in eicosanoid production and decreased cAMP levels. The platelets did not aggregate in response to FAEE alone, but did shorten the time to maximum aggregation with epinephrine. CONCLUSION These studies show that FAEE potentiate platelet activation but do not induce aggregation, presumably because they do not stimulate thromboxane A(2) production.
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Affiliation(s)
- Raneem O Salem
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA
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Blanco PG, Salem RO, Ollero M, Zaman MM, Cluette-Brown JE, Freedman SD, Laposata M. Ethanol administration to cystic fibrosis knockout mice results in increased fatty acid ethyl ester production. Alcohol Clin Exp Res 2006; 29:2039-45. [PMID: 16340462 DOI: 10.1097/01.alc.0000187593.86202.e8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Fatty acid ethyl esters (FAEE) are nonoxidative ethanol metabolites shown to produce toxic effects in the liver and pancreas in vivo and in vitro. Because alcohol-induced chronic pancreatitis is associated with mutations in the gene responsible for cystic fibrosis (CFTR), we hypothesized that CFTR dysfunction leads to increased levels of these toxic nonoxidative ethanol metabolites following alcohol administration. METHODS Cystic fibrosis (CF) and wild-type (WT) mice were injected intraperitoneally with 1, 2, or 3 g/kg of 50% ethanol. Mice were sacrificed and the liver and pancreas removed for FAEE analysis. RESULTS The mean FAEE concentration (pmol/g) detected in the liver of cftr mice following injection with 2 g/kg of ethanol was significantly greater than the amount detected in WT (p < 0.005). A similar trend in FAEE concentration was seen in the pancreas, but the difference was not statistically different. In both the liver and pancreas, analysis of individual FAEE species demonstrated a selective increase in ethyl oleate. CONCLUSION These data show an association between CFTR dysfunction and qualitative and quantitative changes in FAEE in liver and pancreas upon ethanol exposure.
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Affiliation(s)
- Paola G Blanco
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
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17
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Alhomsi K, Laposata M. Fatty acid ethyl ester effects on interleukin-2 production, cyclic AMP synthesis, and calcium influx in human mononuclear cells. Alcohol Clin Exp Res 2006; 30:1121-5. [PMID: 16792558 DOI: 10.1111/j.1530-0277.2006.00129.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Fatty acid ethyl esters (FAEE), nonoxidative ethanol metabolites, are produced by the esterification of fatty acids and ethanol. Plasma and serum FAEE correlate linearly with blood ethanol levels and are present in organs most commonly damaged by ethanol abuse. Our previous studies have shown that there is significant synthesis of FAEE by human mononuclear cells within seconds of exposure to physiologic doses of ethanol. OBJECTIVES We studied the effects of FAEE on selected early events of mononuclear cell activation that follow stimulation with phytohemagglutinin (PHA). Fatty acid ethyl esters induced changes in cytosolic free calcium ([Ca2+]) levels, the production and secretion of interleukin-2 (IL-2) by the cells, and intracellular cAMP concentrations. METHODS A mononuclear fraction of human white blood cells (WBC) was incubated with physiologic doses of FAEE. For experiments involving IL-2 production and calcium influx, PHA-stimulated cells were incubated with 10, 25, 50, or 100 microM ethyl oleate, a representative FAEE species, for 60 minutes. Interleukin-2 was measured by enzyme immunometeric assay and maximum levels of Ca2+ were monitored by spectrofluorimetry. In other experiments, mononuclear cells were incubated with 10, 25, and 50 microM ethyl oleate for 0.08 to 120 minutes, and then the concentration of cAMP was determined by a cAMP competitive enzyme immunoassay system. RESULTS Fatty acid ethyl esters inhibited the PHA-induced IL-2 production and secretion in activated human mononuclear cells. Fatty acid ethyl esters also inhibited PHA-induced [Ca2+] influx into cells in a dose-dependent fashion. There was a rapid increase in the intracellular cAMP concentration of mononuclear cells induced by FAEE, with FAEE dose dependence. The cAMP concentration decreased as the incubation time with FAEE was increased. CONCLUSIONS Fatty acid ethyl esters inhibited PHA-stimulated IL-2 production and Ca2+ influx into human mononuclear cells and elevated intracellular cAMP concentration. These changes in mononuclear cell signaling may be associated with the immunosuppression associated with alcohol abuse.
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Affiliation(s)
- Khaled Alhomsi
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA
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Salem RO, Laposata M, Rajendram R, Cluette-Brown JE, Preedy VR. The total body mass of fatty acid ethyl esters in skeletal muscles following ethanol exposure greatly exceeds that found in the liver and the heart. Alcohol Alcohol 2006; 41:598-603. [PMID: 16980711 DOI: 10.1093/alcalc/agl069] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
AIMS Skeletal muscle appears to be susceptible to chronic and acute excess alcohol intake, giving rise to alcoholic myopathy, a common disease among alcoholics. Fatty acid ethyl esters (FAEE), non-oxidative metabolites of ethanol, have been shown to be toxic to cells in vitro and in vivo. We hypothesized that accumulation of FAEE in skeletal muscle could contribute to the development of alcoholic myopathy. METHODS Male wistar rats were treated either with 75 mmol ethanol/kg body weight or saline, in the fed state or starved for 1 or 2 days before administration. Rats were thus divided into the following groups: fed-saline (n = 8); fed-ethanol (n = 8); starved 1 day, saline (n = 8); starved 1 day, ethanol (n = 9); starved 2 days, saline (n = 7); and starved 2 days, ethanol (n = 8). At the end of the incubation, skeletal muscles (abdominal and gastrocnemius), liver, and heart were isolated and processed for FAEE isolation and analysis by gas chromatography-mass spectrometry (GC-MS). RESULTS Total mass of FAEE in the muscles was much greater than that found in the liver and the heart. In general, the animals that were fasted for 1 day and received ethanol had the highest FAEE levels among the three groups of animals. The major ethyl ester species in all cases were ethyl 16:0, ethyl 18:0, ethyl 18:1 n-9, and ethyl 18:2 n-6. Ethyl 20:4 n-6 and ethyl 22:6 n-3 were also present, except in the fasted 1-day group, where ethyl 22:6 disappeared, though it reappeared in the fasted 2-day group. CONCLUSION These findings demonstrate that skeletal muscles contain high levels of FAEE that are synthesized in the body after ethanol exposure. The concentration of FAEE in skeletal muscle in this study was very similar to FAEE concentration in the liver. This differs from previous studies suggesting a low concentration of skeletal muscle FAEE with ethanol exposure.
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Affiliation(s)
- Raneem O Salem
- Massachusetts General Hospital and Harvard Medical School, Division of Laboratory Medicine, Boston, MA 02114, USA
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Yoerger DM, Best CA, McQuillan BM, Supple GE, Guererro JL, Cluette-Brown JE, Hasaba A, Picard MH, Stone JR, Laposata M. Rapid fatty acid ethyl ester synthesis by porcine myocardium upon ethanol infusion into the left anterior descending coronary artery. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 168:1435-42. [PMID: 16651611 PMCID: PMC1606583 DOI: 10.2353/ajpath.2006.050537] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Fatty acid ethyl esters (FAEEs), nonoxidative metabolites of ethanol, have been implicated in ethanol-induced heart injury. To assess the in vivo production of FAEEs by myocardial tissue, we used a modified ethanol ablation procedure in pigs. A controlled 60-minute ethanol infusion was administered into the distal left anterior descending coronary artery in seven swine; serial blood sampling of the coronary sinus and peripheral vein before, during, and after infusion allowed measurement of FAEE production and ethanol levels in the coronary sinus and the peripheral circulation. In a single animal, FAEEs were also quantified from nine different sites within the myocardium. FAEEs were produced by the heart within 5 minutes of exposure to ethanol, with very high concentrations of FAEEs detected in coronary sinus blood. Significant variability in amounts of FAEEs was detected in different regions of the heart tissue. A strong correlation was found between coronary sinus FAEEs and ethanol concentration (r = 0.9241, P < 0.00001). FAEE production by the heart after delivery of ethanol into the left anterior descending coronary artery was rapid, reaching levels in the coronary sinus blood 4 to 10 times greater than that found in peripheral blood after ethanol intake. These data demonstrate that FAEEs may be mediators of ethanol-induced cardiotoxicity.
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Affiliation(s)
- Danita M Yoerger
- Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA.
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20
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Best CA, Sarkola T, Eriksson CJP, Cluette-Brown JE, Laposata M. Increased Plasma Fatty Acid Ethyl Ester Levels Following Inhibition of Oxidative Metabolism of Ethanol by 4-Methylpyrazole Treatment in Human Subjects. Alcohol Clin Exp Res 2006; 30:1126-31. [PMID: 16792559 DOI: 10.1111/j.1530-0277.2006.00138.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Recent experimental evidence suggests that fatty acid ethyl esters (FAEE), nonoxidative metabolites of ethanol, mediate ethanol-induced organ damage. A direct association between pancreas-specific toxicity and increased levels of FAEE following inhibition of the oxidative metabolism of ethanol by 4-methylpyrazole (4-MP) has previously been shown in studies with rats. METHODS We obtained plasma samples from 32 healthy human volunteers who drank ethanol following 4-MP or placebo ingestion to determine whether in vivo inhibition of oxidative metabolism of ethanol causes a shift to nonoxidative metabolism of ethanol and the subsequent production of increased levels of FAEE. Plasma FAEE were isolated by solid-phase extraction and quantified by gas chromatography-mass spectrometry (GC-MS). RESULTS Plasma FAEE levels in subjects receiving 4-MP treatment before ethanol consumption were elevated compared with plasma FAEE concentrations taken from control subjects who received a placebo before ethanol ingestion. Increased FAEE levels in the 4-MP treatment group occurred after peak blood ethanol, and peak FAEE levels were achieved. There was a correlation between the blood ethanol and the plasma FAEE levels, and the correlation persisted in the presence or absence of 4-MP. The peak FAEE values were greater in men than in women, with or without 4-MP treatment. CONCLUSIONS Our results indicate that the in vivo inhibition of the oxidative metabolism of ethanol using 4-MP results in an increased circulating concentration of FAEE, products of the nonoxidative metabolism of ethanol.
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Affiliation(s)
- Catherine A Best
- Department of Pathology, Division of Laboratory Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA
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21
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Best CA, Laposata M, Proios VG, Szczepiorkowski ZM. METHOD TO ASSESS FATTY ACID ETHYL ESTER BINDING TO ALBUMIN. Alcohol Alcohol 2006; 41:240-6. [PMID: 16554377 DOI: 10.1093/alcalc/agl009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AIMS To develop a method to assess the relative binding of fatty acid ethyl esters (FAEE) and free fatty acids (FFA) to albumin, and to determine if binding affinity is related to fatty acid chain length and or degree of saturation. METHODS Radiolabelled ethyl-[14C] oleate bound to albumin was challenged with various ratios of FFA to FAEE. The displacement of ethyl-[14C] oleate by FFA was visualized and quantitated through a combination of native-PAGE, autoradiography, and liquid scintillation counting (LSC). RESULTS As the ratio of FFA to FAEE increased from 0:1 to 12:1, for all fatty acids tested (myristate, palmitate, stearate, oleate, linoleate, and arachidonate), ethyl-[14C] oleate displacement increased, when expressed as radioactivity (in DPM) as a percentage of control. In contrast, ethyl oleate did not displace stearate or oleate from albumin at molar ratios up to 5:1 (FAEE:FFA). CONCLUSIONS The method developed gave reproducible visualization of noncovalent binding of radiolabelled FAEE to albumin. The combination of native-PAGE and autoradiography LSC works well in assessing the binding properties of albumin and radiolabelled FAEE. The data indicate preferential binding of FFA over FAEE to albumin with six different FFA displacing FAEE to an approximately equal extent.
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Affiliation(s)
- Catherine A Best
- Department of Biomedical Sciences, Northeastern University, Boston, MA 02115, USA.
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22
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Alhomsi K, Cluette-Brown JE, Laposata M. Fatty Acid Ethyl Esters in Human Mononuclear Cells: Production by Endogenous Synthesis Greatly Exceeds the Uptake of Preformed Ethyl Esters. Alcohol Clin Exp Res 2006; 30:560-6. [PMID: 16499498 DOI: 10.1111/j.1530-0277.2006.00062.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
BACKGROUND Fatty acid ethyl esters (FAEE) are nonoxidative metabolites of ethanol. They are esterification products of ethanol and fatty acids. Fatty acid ethyl esters have been implicated as important mediators of ethanol-induced cytotoxicity, organ damage, and disease. In addition, they serve as specific and sensitive biomarkers for ethanol intake. Following ethanol consumption, FAEE are found in circulating blood bound to albumin or/and lipoproteins. OBJECTIVES Using a mononuclear fraction of white blood cells (WBC) exposed to ethanol, we investigated FAEE synthesis. We then determined the amount of uptake of preformed FAEE presented to the cells and compared the amounts of FAEE within the cells that were derived from endogenous synthesis with the amount derived from uptake of exposure FAEE. We also measured the persistence of FAEE within these cells and assessed the fate of the FAEE-associated fatty acid upon FAEE hydrolysis. METHODS A mononuclear fraction of human WBC was incubated with 25, 50, or 100 mM ethanol for 0.08 to 120 minutes, and FAEE synthesis was measured by gas chromatography/mass spectrometry. In other experiments, mononuclear cells were incubated with 25, 50, and/or 100 microM [3H]ethyl oleate, a representative FAEE species, for 0.08-120 minutes, and FAEE uptake and hydrolysis were measured. RESULTS The total FAEE formed by treating the cells with 25 mM ethanol, which represents a physiologic dose achievable with excess alcohol intake, greatly exceeded the FAEE within cells derived from uptake of 100 microM ethyl oleate, which represents a supraphysiologic dose. There was hydrolysis of FAEE by human mononuclear cells, with free fatty acids as major metabolites of FAEE hydrolysis. Unlike any other cell type or homogenate studied, the only ethyl ester formed by human mononuclear cells exposed to ethanol was ethyl oleate. CONCLUSIONS There is significant synthesis of FAEE by human mononuclear cells within seconds of exposure to physiologic doses of ethanol. The amount of FAEE in these cells derived from endogenous synthesis greatly exceeds the amount acquired by exogenous uptake.
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Affiliation(s)
- Khaled Alhomsi
- Department of Pathology, Division of Laboratory Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA
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23
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Kulig CC, Beresford TP, Everson GT. Rapid, accurate, and sensitive fatty acid ethyl ester determination by gas chromatography-mass spectrometry. ACTA ACUST UNITED AC 2006; 147:133-8. [PMID: 16503243 DOI: 10.1016/j.lab.2005.11.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2005] [Revised: 09/30/2005] [Accepted: 11/02/2005] [Indexed: 01/19/2023]
Abstract
BACKGROUND Fatty acid ethyl esters (FAEEs) are useful markers of ongoing alcohol use and may be associated with alcohol-induced damage to the liver and pancreas. In this article, we describe a novel method for rapid determination of the three major FAEEs found in human plasma. METHODS Internal standard, ethyl heptadecanoate, was added to plasma samples, and FAEEs were isolated by acetone precipitation, hexane lipid extraction, and amino-propyl silica solid phase extraction. FAEEs were quantitated by gas chromatography-mass spectrometry (GC-MS) using a nonpolar dimethylpolysiloxane column. The accuracy, precision, specificity, and sensitivity of the assay were defined from plasma samples from recently drinking and abstinent persons, with and without the addition of FAEEs. RESULTS Individual FAEE peaks demonstrated excellent resolution. Instrument time was reduced by more than 60%. The lower limit of detection was 5 to 10 nM, and the lower limit of quantitation for each FAEE was 60 nM (for 22 samples with known concentration 60 nM, x +/-SD: 61 +/- 5.7, 57 +/- 5.7, and 57 +/- 5.9 nM, for ethyl palmitate, ethyl oleate, and ethyl stearate, respectively). Instrument precision (coefficient of variance, CV) for these three FAEEs was 0.3%, 0.4%, and 0.7%, respectively. Intra-assay precision (CV) for total FAEEs was less than 7%. FAEEs were absent in 49 samples from abstinent persons. FAEEs were detected in all 76 samples with associated positive blood alcohol levels. CONCLUSIONS Our method of FAEE analysis is rapid and potentially useful in research and clinical studies. FAEE determination using this method is precise, accurate, sensitive, and specific and deserves broader application.
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Affiliation(s)
- Clark C Kulig
- Division of Gastroenterology and Hepatology, University of Colorado Health Sciences Center, Denver, Colorado.
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24
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Aleryani SL, Cluette-Brown JE, Khan ZA, Hasaba H, Lopez de Heredia L, Laposata M. Fatty acid methyl esters are detectable in the plasma and their presence correlates with liver dysfunction. Clin Chim Acta 2005; 359:141-9. [PMID: 15894299 DOI: 10.1016/j.cccn.2005.03.038] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2004] [Revised: 02/02/2005] [Accepted: 03/21/2005] [Indexed: 11/15/2022]
Abstract
BACKGROUND Methanol is a component of certain alcoholic beverages and is also an endogenously formed product. On this basis, we have proposed that methanol may promote synthesis of fatty acid methyl esters (FAMEs) in the same way that ethanol promotes fatty acid ethyl ester (FAEE) synthesis. We tested the hypothesis that FAMEs appear in the blood after ethanol intake. METHODS Patient plasma samples obtained from our laboratory (n=78) were grouped according to blood ethanol concentrations (intoxicated, blood ethanol >800 mg/l) and non-intoxicated. These samples were further subdivided into groups based on whether the patient had normal or abnormal liver function tests (abnormal, defined as > or =1 abnormality of plasma alanine and aspartate aminotransferase, albumin, total bilirubin, and alkaline phosphatase). A separate set of plasma samples were also divided into normal and abnormal groups based on pancreatic function tests (amylase and lipase). There were no patients with detectable ethanol in this group. Patients with abnormalities in pancreatic function tests were included upon recognition of endogenously produced FAMEs by patients with liver function test abnormalities. FAMEs were extracted from plasma and individual species of FAMEs quantified by gas chromatography-mass spectrometry (GC/MS). RESULTS Increased concentrations of FAME were found in patient samples with evidence of liver dysfunction, regardless of whether or not they were intoxicated (n=21, p=0.01). No significant differences in plasma FAME concentrations were found between patients with normal (n=15) versus abnormal pancreatic function tests (n=22, p=0.72). CONCLUSIONS The presence of FAMEs in human plasma may be related to the existence of liver disease, and not to blood ethanol concentrations or pancreatic dysfunction. The metabolic pathways associated with FAME production in patients with impaired liver function remain to be identified.
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Affiliation(s)
- Samir Lutf Aleryani
- Department of Clinical Biochemistry, School of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
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25
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Borucki K, Schreiner R, Dierkes J, Jachau K, Krause D, Westphal S, Wurst FM, Luley C, Schmidt-Gayk H. Detection of Recent Ethanol Intake With New Markers: Comparison of Fatty Acid Ethyl Esters in Serum and of Ethyl Glucuronide and the Ratio of 5-Hydroxytryptophol to 5-Hydroxyindole Acetic Acid in Urine. Alcohol Clin Exp Res 2005; 29:781-7. [PMID: 15897723 DOI: 10.1097/01.alc.0000164372.67018.ea] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND At present, recent ethanol consumption can be routinely detected with certainty only by direct measurement of ethanol concentration in blood or urine. Because ethanol is rapidly eliminated from the circulation, however, the time span for this detection is in the range of hours. Several new markers have been proposed to extend the detection interval, but their characteristics have not yet justified their use in routine clinical practice. We therefore investigated three new markers and compared their kinetics and sensitivities: (1) fatty acid ethyl esters (FAEEs) in serum, (2) ethyl glucuronide (EtG) in urine, and (3) the ratio of 5-hydroxytryptophol to 5-hydroxyindole acetic acid (5-HTOL/5-HIAA) in urine. METHODS Seventeen healthy men participated in a drinking experiment. Blood and urine samples were collected twice daily on three consecutive days and once daily on days 4 and 5. Ethanol concentration was determined by gas chromatography, FAEE levels, by gas chromatography with mass spectrometry, EtG concentration, by liquid chromatography-tandem mass spectrometry, and 5-HTOL/5-HIAA ratio, by high-performance liquid chromatography. RESULTS The peak serum ethanol concentrations of the subjects ranged from 5.4 to 44.7 mmol/liter (mean +/- SD, 30.1 +/- 9.1 mmol/liter). In the case of the serum ethanol determination, 100% sensitivity was reached only immediately after the end of the drinking experiment, and in the case of FAEE levels and 5-HTOL/5-HIAA ratio, it tested for 6.7 hr after the end of the ethanol intake. Thereafter, these latter parameters declined until 15.3 hr (FAEEs) and 29.4 hr (5-HTOL/5-HIAA), subsequently remaining in a stable range until 78.5 hr without further decrease. In contrast, EtG concentration showed 100% sensitivity until 39.3 hr and thereafter decreased, falling to below the limit of quantification of 0.1 mg/liter at 102.5 hr. CONCLUSION After moderate drinking, EtG in the urine proved to be a superior marker of recent ethanol consumption in healthy subjects. This is because EtG is a direct ethanol metabolite, it occurs in the urine only when ethanol has been consumed, and its sensitivity remains at the level of 100% for 39.3 hr.
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Affiliation(s)
- K Borucki
- Institute for Clinical Chemistry and Biochemistry, Magdeburg University Hospital, Magdeburg, Germany.
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26
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Bisaga A, Laposata M, Xie S, Evans SM. COMPARISON OF SERUM FATTY ACID ETHYL ESTERS AND URINARY 5-HYDROXYTRYPTOPHOL AS BIOCHEMICAL MARKERS OF RECENT ETHANOL CONSUMPTION. Alcohol Alcohol 2005; 40:214-8. [PMID: 15797884 DOI: 10.1093/alcalc/agh154] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AIMS To examine the effects of an acute dose of ethanol on serum fatty acid ethyl esters (FAEEs) concentration and urinary 5-hydroxytryptophol (5-HTOL)/5-hydroxyindole-3-acetic acid (5-HIAA) ratio. METHODS Sixteen (14 male, 2 female) heavy alcohol drinkers were tested in a single, 2-day long session. Six participants received 1.5 g/l of ethanol/l of body water (approximately 0.75 g/kg of body weight, low dose group: LD) and 10 participants received 2.0 g/l of ethanol ( approximately 1.0 g/kg of body weight, high dose group: HD) in four divided doses every 20 min. Blood, urine, and breath samples were collected repeatedly over 36 h following the ingestion of ethanol and were analyzed for the presence of FAEE, 5-HTOL/5-HIAA, and ethanol, respectively. Serum gamma-glutamyltransferase (GGT), a marker of chronic ethanol use, was also included. RESULTS The breath ethanol level peaked approximately 1 h after the last dose, at 95 and 120 mg/dl for the LD and HD groups, respectively. The mean ratio of urinary 5-HTOL/5-HIAA was significantly elevated 5 and 9 h after ethanol administration, but returned to baseline 13 h after ethanol administration. This ratio was twice as high for the HD group compared with the LD group. Serum levels of FAEEs were significantly elevated at 5 h, but not 13 h after ethanol administration. There were no time-dependent changes in serum GGT levels. CONCLUSIONS Measuring the levels of FAEE and 5-HTOL/5-HIAA ratio provides a convenient method to detect recent, particularly binge-type, ethanol use, but these measures may have limited applicability in detecting ethanol use in traditional clinical trial settings.
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Affiliation(s)
- Adam Bisaga
- Division on Substance Abuse, NYS Psychiatric Institute and Columbia University, New York, NY, USA.
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Aydin HH, Celik HA, Deveci R, Karacali S, Saydam G, Bedii Omay S, Batur Y. Induction of apoptosis by fatty acid ethyl esters in HepG2 cells. Food Chem Toxicol 2005; 43:139-45. [PMID: 15582206 DOI: 10.1016/j.fct.2004.09.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2004] [Accepted: 09/16/2004] [Indexed: 10/26/2022]
Abstract
Fatty acid ethyl esters (FAEEs) are esterification products of ethanol and fatty acids which have been found particularly in the organ damaged by ethanol abuse. To evaluate any effect of FAEEs on HepG2 cells, we added FAEEs to cell culture medium. Electrophoresis of DNA from HepG2 cells exposed to 18.5 microM ethyl palmitate (EP) and 10.6 microM ethyl stearate (ES) for 24 h revealed a smear which is typical of non-specific degradation by DNA ladder assay. Apoptosis was characterized by electron microscopy, flow cytometry revealed that the cell cycle of HepG2 cells was perturbed by exposure to FAEEs. In the present study we demonstrate that treatment of HepG2 cells with EP and ES induces apoptosis, as well as perturbing the cell cycle as the number of cells in the G(2)/M and S phases decreased.
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Affiliation(s)
- Hikmet Hakan Aydin
- Department of Biochemistry, Ege University, School of Medicine, Bornova, 35100 Izmir, Turkey.
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Kaphalia BS, Cai P, Khan MF, Okorodudu AO, Ansari GAS. Fatty acid ethyl esters: markers of alcohol abuse and alcoholism. Alcohol 2004; 34:151-8. [PMID: 15902908 DOI: 10.1016/j.alcohol.2004.07.013] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Chronic alcoholism, which is associated with hepatic, pancreatic, and myocardial diseases, is one of the major health problems in the United States with high morbidity and mortality. Many individuals who abuse alcohol chronically die even before reaching the clinical stage of the disease. Reliable biomarkers of the diseases induced by chronic alcohol abuse, as well as for alcoholism, currently are not available. In the current study, we measured plasma concentrations of fatty acid ethyl esters [(FAEEs), nonoxidative metabolites of ethanol] in 39 patients with a detectable concentration of alcohol in their blood samples. In turn, we determined the relation of FAEE concentrations with blood alcohol concentration (BAC). Of 39 patients in whom we evaluated this relation, only five had a history of chronic alcohol abuse, and six had a history of acute alcohol abuse. Patients' age ranged from 25 to 71 years. Within this age range, greater concentrations of FAEEs were found in the plasma samples obtained from patients in the 41- to 50-year age group. There were no sex-related differences in BAC, nor in FAEE concentrations. Thirteen patients had a BAC greater than 300 mg%. For 11 patients, the BAC ranged between 200 and 299 mg%, and, for 12 patients, the BAC ranged between 100 and 199 mg%. In comparison with findings for patients with a BAC that ranged between 100 and 299 mg%, the FAEE concentrations were approximately twofold higher in patients with a BAC greater than 300 mg%. Ethyl palmitate and ethyl oleate were the main FAEEs detected in most patients. In general, FAEE concentrations increased with increasing BAC. However, in comparison with patients with a history of acute alcohol abuse, a greater increase in total FAEE concentrations was observed in patients with a history of chronic alcohol abuse (4,250 ng/ml and 15,086 ng/ml, respectively). Fatty acid ethyl esters were either detected in trace amounts or not detectable in the plasma of control subjects with no known alcohol ingestion. These results support our hypothesis that nonoxidative metabolism of ethanol to FAEEs is an important pathway of ethanol disposition during chronic alcohol abuse, and that FAEE concentrations can be a more reliable biomarker of chronic alcohol abuse than a history of acute alcohol abuse.
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Affiliation(s)
- Bhupendra S Kaphalia
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
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Hasaba A, Cluette-Brown JE, Laposata M. Stearic acid stimulates FA ethyl ester synthesis in HepG2 cells exposed to ethanol. Lipids 2004; 38:1051-5. [PMID: 14669970 DOI: 10.1007/s11745-006-1160-3] [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: 10/21/2022]
Abstract
FA ethyl esters (FAEE) are nonoxidative metabolites of ethanol produced by the esterification of FA and ethanol. FAEE have been implicated as mediators of ethanol-induced organ damage in vivo and in vitro, and are markers of ethanol intake. Upon ethanol intake, FAEE are synthesized in the liver and pancreas in significant quantities. There is limited information on the stimulation of FAEE synthesis upon addition of exogenous FA in vitro. HepG2 cells were incubated with ethanol alone, ethanol with 25 microM linoleate, and ethanol with 25 microM stearate. The amount of FAEE in human hepatoblastoma (HepG2) cells was determined 1-3 h after ethanol and FA addition. Stearate increased the FAEE concentration in HepG2 cells when incubated with the cells for 1 h, whereas linoleate did not increase the cellular FAEE concentration at any time. Ethyl palmitate, ethyl stearate, and ethyl oleate were the predominant FAEE species identified in all cases, independent of the specific supplemental FA added to the medium.
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Affiliation(s)
- Ali Hasaba
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA
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Haber PS, Apte MV, Moran C, Applegate TL, Pirola RC, Korsten MA, McCaughan GW, Wilson JS. Non-oxidative metabolism of ethanol by rat pancreatic acini. Pancreatology 2004; 4:82-9. [PMID: 15056978 DOI: 10.1159/000077608] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2003] [Accepted: 01/28/2004] [Indexed: 12/11/2022]
Abstract
BACKGROUND The pathogenesis of alcoholic pancreatitis may involve the metabolism of ethanol (via oxidative and non-oxidative pathways) within the pancreas. The aims of this study were to determine the rate of non-oxidative metabolism in isolated rat pancreatic acini and to compare this to the rate of ethanol oxidation. METHODS Pancreatic acini were isolated from male Sprague-Dawley rats and incubated with (14)C-ethanol. Radiolabelled fatty acid ethyl esters (non-oxidative metabolites) were isolated from lipid extracts by thin-layer chromatography. Radiolabelled acetate (oxidative metabolite) was isolated from the incubation medium by ion-exchange chromatography. RESULTS Non-oxidative metabolism by isolated pancreatic acini was demonstrated. At 50 and 100 mmol/l ethanol, fatty acid ethyl ester concentrations were 49.6 +/- 13.3 and 199 +/- 93 micromol/l, respectively. These levels have previously been shown to result in tissue injury. Non-oxidative metabolism was increased 9-fold by addition of oleic acid and inhibited by the lipase inhibitor, tetrahydrolipstatin, by 91.05 +/- 1.99%. The rate of oxidative metabolism was 21-fold higher than that of non-oxidative metabolism. CONCLUSIONS Intact pancreatic cells metabolize ethanol by the non-oxidative pathway, generating fatty acid ethyl esters at a rate sufficient to cause pancreatic damage. Oxidative metabolism of ethanol occurs at a much higher rate and may also play a role in pancreatitis.
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Affiliation(s)
- Paul S Haber
- Pancreatic Research Group, University of New South Wales, Sydney, Australia
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Lugea A, Gukovsky I, Gukovskaya AS, Pandol SJ. Nonoxidative ethanol metabolites alter extracellular matrix protein content in rat pancreas. Gastroenterology 2003; 125:1845-59. [PMID: 14724836 DOI: 10.1053/j.gastro.2003.09.021] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND & AIMS The mechanisms involved in ethanol-induced pancreas fibrosis are poorly understood. Here we show that fatty acid ethyl esters (FAEEs), nonoxidative ethanol metabolites, increase extracellular matrix (ECM) protein levels in pancreas. METHODS Rat pancreatic acini were incubated for 1-4 hours with FAEEs or acetaldehyde. In another set of experiments, rats received an intravenous infusion of FAEEs for 6 hours. Collagens were assessed by a hydroxyproline assay. Laminin and fibronectin were analyzed by Western blotting. Gene expression of ECM proteins was measured by conventional and real-time reverse-transcription polymerase chain reaction (RT-PCR). Matrix metalloproteinase (MMP), plasmin, and urokinase-type plasminogen activator (uPA) activities were determined by zymography and fluorogenic assays. RESULTS FAEEs increased collagen, laminin, and fibronectin levels in pancreatic acini without affecting messenger RNA (mRNA) expression for these proteins. Actinomycin D, a transcriptional inhibitor, did not block the increase in ECM proteins induced by FAEEs. FAEEs reduced the activity of the serine protease, plasmin, and that of the uPA. Consistent with these results, the serine protease inhibitor aprotinin reproduced the effects of FAEEs and prevented the further increase in ECM proteins induced by FAEEs. In vivo administration of FAEEs reduced plasmin and uPA activities and increased ECM protein levels in pancreas. Acetaldehyde had minor effects on ECM protein levels and did not affect plasmin activity. CONCLUSIONS FAEEs increase ECM protein levels in pancreas. The results suggest that this effect is caused primarily by an inhibition in ECM degradation via serine proteases including the plasminogen system.
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Affiliation(s)
- Aurelia Lugea
- University of Southern California-University of California Research Center for Alcoholic Liver and Pancreatic Diseases, Veterans Affairs Greater Los Angeles Healthcare System, 90073, USA.
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Best CA, Cluette-Brown JE, Teruya M, Teruya A, Laposata M. Red blood cell fatty acid ethyl esters: a significant component of fatty acid ethyl esters in the blood. J Lipid Res 2003; 44:612-20. [PMID: 12562827 DOI: 10.1194/jlr.m200398-jlr200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although alcohol abuse is known to cause an array of ethanol-induced red blood cell (RBC) abnormalities, the underlying molecular mechanisms remain poorly understood. Fatty acid ethyl esters (FAEEs) are toxic, nonoxidative ethanol metabolites that have been found in blood, plasma, and tissues. Because FAEEs have been shown to be incorporated into phospholipid bilayers, we conducted a controlled ethanol intake study to test the hypothesis that FAEEs accumulate and persist within RBCs following ethanol ingestion. We demonstrated that RBC FAEEs account for approximately 5% to 20% of total whole-blood FAEEs, and that the fatty acid composition of FAEEs in RBCs and plasma are different and vary differently over time. These data indicate that a significant percentage of FAEEs in the blood is associated with RBCs and that the metabolism of RBC FAEEs and that of plasma FAEEs (bound to albumin or lipoproteins) are largely independent.
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Affiliation(s)
- Catherine A Best
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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Laposata M, Hasaba A, Best CA, Yoerger DM, McQuillan BM, Salem RO, Refaai MA, Soderberg BL. Fatty acid ethyl esters: recent observations. Prostaglandins Leukot Essent Fatty Acids 2002; 67:193-6. [PMID: 12324241 DOI: 10.1054/plef.2002.0418] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Fatty acid ethyl esters (FAEE), esterification products of fatty acids and ethanol, have been shown to be mediators of ethanol-induced cell injury and their presence in the blood and tissues is a marker of ethanol intake. Recently, it has been shown that FAEE are produced within seconds of infusion of ethanol into the heart, when using a protocol similar to that used for myocardial ablation. This raises the possibility that the mechanism for the death of myocytes in cardiac ablation involves the generation of toxic FAEE. It has also been recently demonstrated that chronic alcoholics have a high concentration of a specific FAEE species--ethyl oleate. The use of the serum ethyl oleate concentration may be helpful in differentiating binge drinkers from chronic alcoholics.
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Affiliation(s)
- Michael Laposata
- Department of Pathology, Division of Laboratory Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
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Werner J, Saghir M, Warshaw AL, Lewandrowski KB, Laposata M, Iozzo RV, Carter EA, Schatz RJ, Fernández-Del Castillo C. Alcoholic pancreatitis in rats: injury from nonoxidative metabolites of ethanol. Am J Physiol Gastrointest Liver Physiol 2002; 283:G65-73. [PMID: 12065293 DOI: 10.1152/ajpgi.00419.2001] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The mechanism by which alcohol injures the pancreas remains unknown. Recent investigations suggest a role for fatty acid ethyl ester (FAEE), a nonoxidative metabolite of ethanol, in the pathogenesis of alcohol pancreatitis. In this study, we characterized ethanol-induced injury in rats and evaluated the contribution of oxidative and nonoxidative ethanol metabolites in this form of acute pancreatitis. Pancreatic injury in rats was assessed by edema, intrapancreatic trypsinogen activation, and microscopy after infusing ethanol with or without inhibitors of oxidative ethanol metabolism. Plasma and tissue levels of FAEE and ethanol were measured and correlated with pancreatic injury. Ethanol infusion generated plasma and tissue FAEE and, in a dose-dependent fashion, induced a pancreas-specific injury consisting of edema, trypsinogen activation, and formation of vacuoles in the pancreatic acini. Inhibition of the oxidation of ethanol significantly increased both FAEE concentration in plasma and pancreas and worsened the pancreatitis-like injury. This study provides direct evidence that ethanol, through its nonoxidative metabolic pathway, can produce pancreas-specific toxicity in vivo and suggests that FAEE are responsible for the development of early pancreatic cell damage in acute alcohol-induced pancreatitis.
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Affiliation(s)
- Jens Werner
- Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
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35
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Hannuksela ML, Liisanantti MK, Savolainen MJ. Effect of alcohol on lipids and lipoproteins in relation to atherosclerosis. Crit Rev Clin Lab Sci 2002; 39:225-83. [PMID: 12120782 DOI: 10.1080/10408360290795529] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Several studies indicate that light-to-moderate alcohol consumption is associated with a low prevalence of coronary heart disease. An increase in high-density lipoprotein (HDL) cholesterol is associated with alcohol intake and appears to account for approximately half of alcohol's cardioprotective effect. In addition to changes in the concentration and composition of lipoproteins, alcohol consumption may alter the activities of plasma proteins and enzymes involved in lipoprotein metabolism: cholesteryl ester transfer protein, phospholipid transfer protein, lecithin:cholesterol acyltransferase, lipoprotein lipase, hepatic lipase, paraoxonase-1 and phospholipases. Alcohol intake also results in modifications of lipoprotein particles: low sialic acid content in apolipoprotein components of lipoprotein particles (e.g., HDL apo E and apo J) and acetaldehyde modification of apolipoproteins. In addition, "abnormal" lipids, phosphatidylethanol, and fatty acid ethyl esters formed in the presence of ethanol are associated with lipoproteins in plasma. The effects of lipoproteins on the vascular wall cells (endothelial cells, smooth muscle cells, and monocyte/macrophages) may be modulated by ethanol and the alterations further enhanced by modified lipids. The present review discusses the effects of alcohol on lipoproteins in cholesterol transport, as well as the novel effects of lipoproteins on vascular wall cells.
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Affiliation(s)
- Minna L Hannuksela
- Department of Internal Medicine, Biocenter Oulu, University of Oulu, Finland
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36
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Pathogenesis of Alcoholic Liver Disease???Recent Advances. Alcohol Clin Exp Res 2002. [DOI: 10.1097/00000374-200205000-00020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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37
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Nanji AA, Su GL, Laposata M, French SW. Pathogenesis of Alcoholic Liver Disease-Recent Advances. Alcohol Clin Exp Res 2002. [DOI: 10.1111/j.1530-0277.2002.tb02598.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Gukovskaya AS, Mouria M, Gukovsky I, Reyes CN, Kasho VN, Faller LD, Pandol SJ. Ethanol metabolism and transcription factor activation in pancreatic acinar cells in rats. Gastroenterology 2002; 122:106-18. [PMID: 11781286 DOI: 10.1053/gast.2002.30302] [Citation(s) in RCA: 123] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND & AIMS Ethanol metabolism by pancreatic acinar cells and the role of its metabolites in ethanol toxicity to the pancreas remain largely unknown. Here, we characterize ethanol metabolism in pancreatic acinar cells and determine the effects of ethanol metabolites on nuclear factor kappa B (NF-kappa B) and activator protein (AP)-1, transcription factors that are activated in pancreatitis and mediate expression of inflammatory molecules critical for this disease. METHODS We measured activities of fatty acid ethyl ester (FAEE) synthase and alcohol dehydrogenase (ADH), as well as accumulation of ethanol metabolites. We measured the effects of ethanol and its metabolites on NF-kappa B and AP-1 activation by using a gel shift assay. RESULTS Pancreas metabolizes ethanol via both oxidative and nonoxidative pathways. Acinar cells are the main source of ethanol metabolism in the pancreas. Compared with the liver, FAEE synthase activity in the pancreas is greater, whereas that of ADH is much less. FAEEs activated NF-kappa B and AP-1, whereas acetaldehyde inhibited NF-kappa B activation. Ethanol decreased NF-kappa B binding activity in acinar cells, which was potentiated by cyanamide. CONCLUSION Oxidative and nonoxidative ethanol metabolites regulate transcription factors differently in pancreatic acinar cells. Ethanol may regulate NF-kappa B and AP-1 positively or negatively, depending on which metabolic pathway's effect predominates. These regulatory mechanisms may play a role in ethanol toxicity to the pancreas.
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Affiliation(s)
- Anna S Gukovskaya
- Department of Medicine, Veterans Affairs Greater Los Angeles Healthcare System and University of California, Los Angeles 90073, California, USA.
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39
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Kaphalia BS, Ansari GA. Purification and characterization of rat hepatic microsomal low molecular weight fatty acid ethyl ester synthase and its relationship to carboxylesterases. J Biochem Mol Toxicol 2001; 15:165-71. [PMID: 11424227 DOI: 10.1002/jbt.14] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We reported purification of a high molecular weight (HMW) (ca. 180 kD) and a low molecular weight (LMW) (ca. 60 kD) protein fractions from digitonized rat liver microsomes using ammonium sulfate precipitation followed by ion exchange and gel filtration column chromatography. Both fractions expressed fatty acid ethyl ester (FAEE) synthase as well as p-nitrophenyl acetate (PNPA)-hydrolyzing (esterase) activities. The HMW fraction was found to be a trimer with subunit molecular weight ca. 60 kD and structurally and functionally similar to rat hepatic microsomal carboxylesterase (CE, pI 6.1) and adipose tissue FAEE synthase. In this article, we report further purification and characterization of the LMW (minor) fraction expressing FAEE synthase activity and its structural and functional relationship to hepatic microsomal CEs. Using isoelectric focusing (IEF) followed by gel filtration-high-performance liquid chromatography (GF-HPLC), five proteins were purified, which expressed FAEE synthase as well as PNPA-hydrolyzing activity. The isoelectric point values of 6.5, 5.8, 5.6, 5.3, and 5.0 were found for the purified LMW proteins by IEF and each showed a peak corresponding to ca. 60 kD molecular weight by GF-HPLC, which expressed FAEE synthase as well as PNPA-hydrolyzing activity. Sodium dodecyl sulfate-polyacrylamide gel elecrophoresis (SDS-PAGE) analysis of the GF-HPLC purified LMW proteins revealed that these proteins are monomers (ca. 60 kD). All the purified LMW proteins cross-reacted with antibodies to rat adipose tissue FAEE synthase. Coelution of PNPA-hydrolyzing and FAEE synthase activity at each step of purification and cross-reactivity with rat adipose tissue FAEE synthase antibodies suggest that the purified proteins are related to various hepatic microsomal CEs. This conclusion is further supported by the homology of N-terminal amino acid sequence of the purified LMW proteins to various hepatic microsomal CEs and protease precursors. Therefore, LMW FAEE synthase activity most probably is expressed by various isozymes of hepatic microsomal CEs, which are also involved in the biotransformation of xenobiotic alcohols and amines.
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Affiliation(s)
- B S Kaphalia
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA
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40
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Diczfalusy MA, Björkhem I, Einarsson C, Hillebrant CG, Alexson SE. Characterization of enzymes involved in formation of ethyl esters of long-chain fatty acids in humans. J Lipid Res 2001. [DOI: 10.1016/s0022-2275(20)31590-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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41
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Zybko WC, Cluette-Brown JE, Laposata M. Improved Sensitivity and Reduced Sample Size in Serum Fatty Acid Ethyl Ester Analysis. Clin Chem 2001. [DOI: 10.1093/clinchem/47.6.1120] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Walter C Zybko
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Joanne E Cluette-Brown
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Michael Laposata
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
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42
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Werner J, Saghir M, Fernandez-del Castillo C, Warshaw AL, Laposata M. Linkage of oxidative and nonoxidative ethanol metabolism in the pancreas and toxicity of nonoxidative ethanol metabolites for pancreatic acinar cells. Surgery 2001; 129:736-44. [PMID: 11391373 DOI: 10.1067/msy.2001.113891] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Alcohol abuse is a major cause of pancreatic damage. Recent experimental evidence suggests that fatty acid ethyl esters (FAEE), nonoxidative ethanol metabolites, injure pancreatic acinar cells. Linkage between oxidative and nonoxidative metabolism of ethanol in the pancreas may contribute to increased FAEE levels. METHODS To study the association between oxidative and nonoxidative ethanol metabolism, FAEE concentration and FAEE synthase activity in rat pancreatic and liver homogenates incubated with ethanol were evaluated with and without inhibitors of oxidative ethanol metabolism. For toxicity studies, trypsinogen activation peptide synthesis as a measure of pancreatic cell injury was quantitated in unstimulated and cerulein-stimulated isolated pancreatic acinar cells incubated with ethanol or FAEE. RESULTS Inhibition of oxidative ethanol metabolism results in a 2- to 3-fold increase in nonoxidative ethanol metabolism to FAEE in pancreas and in liver. Both ethanol and FAEE induce increased intracellular trypsinogen activation by more than 50% in the presence of physiologic concentrations of cerulein in vitro. CONCLUSIONS These findings demonstrate that the inhibition of oxidative ethanol metabolism results in an increase in flux through the nonoxidative pathway and support the proposition that alcohol-induced pancreatic injury is mediated at least in part by FAEE, which are important products of pancreatic ethanol metabolism.
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Affiliation(s)
- J Werner
- Department of Surgery, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St., Boston, MA 02114
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43
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Salem RO, Refaai MA, Cluette-Brown JE, Russo JW, Laposata M. Fatty Acid Ethyl Esters in Liver and Adipose Tissues as Postmortem Markers for Ethanol Intake. Clin Chem 2001. [DOI: 10.1093/clinchem/47.4.722] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
AbstractBackground: Fatty acid ethyl esters (FAEEs) are nonoxidative metabolites of ethanol. FAEEs are found in liver, pancreas, and adipose tissues up to 24 h after consumption of ethanol, and on that basis, they are potentially useful markers for ethanol intake. In this study with rats, we investigated the efficacy of using FAEEs in liver and in adipose tissue as postmortem markers for premortem ethanol ingestion.Methods: An animal study was conducted in which test rats received injections of ethanol and control rats received injections of normal saline. The rats were killed 2 h after the injections. The bodies of the animals were stored at 4 °C up to 12 h, and samples of liver and adipose tissues were collected at different time intervals and processed for FAEE quantification. In another set of experiments, the rats received injections and were killed as described above, but bodies of animals from both groups were stored at 4, 25, or 37 °C for up to 72 h, and liver samples were collected and processed for FAEE quantification.Results: FAEEs were detected up to 12 h after death in liver and adipose tissue samples from the bodies of ethanol-treated animals stored at 4 °C; negligible amounts were detected in the bodies of animals that received normal saline. Adipose tissues contained higher amounts of FAEEs than liver, as well as more species: eight FAEE species in adipose tissue and five in liver tissue. Higher concentrations of FAEEs were detected in livers of treated animals stored at 25 °C for up to 48 h than in livers of controls stored under the same conditions.Conclusions: For at least 12 h after death, FAEEs in liver and adipose tissues are useful postmortem markers of premortem ethanol ingestion.
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Affiliation(s)
- Raneem O Salem
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Majed A Refaai
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Joanne E Cluette-Brown
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Joshua W Russo
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Michael Laposata
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
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44
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Hasaba A, Laposata M. The Synthesis and Secretion of Fatty Acid Ethyl Esters From HepG2 Cells Are Stimulated by Lipoproteins and Albumin. Alcohol Clin Exp Res 2001. [DOI: 10.1111/j.1530-0277.2001.tb02219.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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45
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Calabrese V, Scapagnini G, Catalano C, Dinotta F, Bates TE, Calvani M, Stella AM. Effects of acetyl-L-carnitine on the formation of fatty acid ethyl esters in brain and peripheral organs after short-term ethanol administration in rat. Neurochem Res 2001; 26:167-74. [PMID: 11478744 DOI: 10.1023/a:1011003030287] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Increasing evidence suggests that Fatty acid ethyl esters (FAEE) play a central role in ethanol induced organ damage. In the current study we measured FAEE formation in rats after short-term oral administration of ethanol, in the presence and absence of pre-treatment with acetyl-L-carnitine. Ethanol treatment caused a significant increase in the levels of FAEE, particularly in the brain and heart, but also in the kidney and liver. Increases in FAEE were associated with a significant increase in FAEE synthase activity, GSH transferase activity, and lipid hydroperoxide levels. Pretreatment with acetyl-L-carnitine resulted in a significant reduction of FAEE accumulation, decrease in FAEE synthase and GSH transferase activities, and lipid hydroperoxide levels. Administration of acetyl-L-carnitine greatly reduced the metabolic abnormalities due to non-oxidative ethanol metabolism, through an increment in lipid metabolism/turnover and by the modulation of the activities of enzymes associated with FAEE synthesis. These results suggest a potentially important pharmacological role for acetyl-L-carnitine in the prevention of alcohol-induced cellular damage.
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Affiliation(s)
- V Calabrese
- Department of Chemistry, Faculty of Medicine, University of Catania, Italy.
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46
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Laposata M, Kabakibi A, Walden MP, Cluette-Brown JE, Nanji AA, Refaai MA, Werner J, Nanji AA. Differences in the Fatty Acid Composition of Fatty Acid Ethyl Esters in Organs and Their Secretions. Alcohol Clin Exp Res 2000. [DOI: 10.1111/j.1530-0277.2000.tb04565.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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47
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Soderberg BL, Sicinska ET, Blodget E, Cluette-Brown JE, Suter PM, Schuppisser T, Vetter W, Laposata M. Preanalytical Variables Affecting the Quantification of Fatty Acid Ethyl Esters in Plasma and Serum Samples. Clin Chem 1999. [DOI: 10.1093/clinchem/45.12.2183] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractBackground: Fatty acid ethyl esters (FAEEs) are cytotoxic nonoxidative ethanol metabolites produced by esterification of fatty acids and ethanol. FAEEs are detectable in blood up to 24 h after ethanol consumption. The objective of this study was to assess the impact of gender, serum or plasma triglyceride concentration, time and temperature of specimen storage, type of alcoholic beverage ingested, and the rate of ethanol consumption on FAEE concentrations in plasma or serum.Methods: For some studies, subject were recruited volunteers; in others, residual blood samples after ethanol quantification were used. FAEEs were isolated by solid-phase extraction and quantified by gas chromatography–mass spectrometry.Results: For weight-adjusted amounts of ethanol intake, FAEE concentrations were twofold greater for men than women (P ≤0.05). Accounting for triglycerides improved the correlation between blood ethanol concentrations and FAEE concentrations for both men (from r = 0.640 to r = 0.874) and women (from r = 0.619 to r = 0.673). FAEE concentrations did not change when samples were stored at or below 4 °C, but doubled when stored at room temperature for ≥24 h. The type of alcoholic beverage and rate of consumption did not affect FAEE concentrations.Conclusion: These studies advance plasma and serum FAEE measurements closer to implementation as a clinical test for ethanol intake.
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Affiliation(s)
- Britt L Soderberg
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Ewa T Sicinska
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Emily Blodget
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Joanne E Cluette-Brown
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
| | - Paolo M Suter
- Medical Policlinic, University Hospital, Ramistrasse 100, CH-8091, Zurich, Switzerland
| | - Theresa Schuppisser
- Medical Policlinic, University Hospital, Ramistrasse 100, CH-8091, Zurich, Switzerland
| | - Wilhem Vetter
- Medical Policlinic, University Hospital, Ramistrasse 100, CH-8091, Zurich, Switzerland
| | - Michael Laposata
- Division of Laboratory Medicine, Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114
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48
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Naveau S. Rôle des acides gras alimentaires dans la physiopathologie des hépatopathies alcooliques. NUTR CLIN METAB 1999. [DOI: 10.1016/s0985-0562(99)80048-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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49
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Saghir M, Blodget E, Laposata M. The hydrolysis of fatty acid ethyl esters in low-density lipoproteins by red blood cells, white blood cells and platelets. Alcohol 1999; 19:163-8. [PMID: 10548161 DOI: 10.1016/s0741-8329(99)00035-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Fatty acid ethyl esters (FAEE), esterification products of fatty acids and ethanol, have been implicated as toxic mediators of ethanol ingestion. In this study, we investigated the in vitro hydrolysis of FAEE reconstituted in low-density lipoproteins (LDL) when incubated with human blood, cell free plasma, red blood cells, white blood cells, and platelets. We also determined the metabolic fate of the fatty acid originally incorporated in the FAEE following FAEE hydrolysis. When FAEE were incubated with human red blood cells. white blood cells, or platelets, at physiologic cell counts, 80% of the FAEE were hydrolyzed at 2 h. The FAEE-derived fatty acid was predominantly found in phospholipid and free fatty acid fractions. Cell free plasma contained minimal FAEE hydrolytic activity. These studies demonstrate that FAEE are degraded to free fatty acids and ethanol by the cellular elements in the blood. The generation of free fatty acids from extensive hydrolysis of FAEE adds support to the growing concept that at least some of the toxic effects of FAEE are mediated by the free fatty acids generated upon hydrolysis of the ethyl esters.
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Affiliation(s)
- M Saghir
- Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston 02114, USA
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Kaphalia BS, Green SM, Ansari GA. Fatty acid ethyl and methyl ester synthases, and fatty acid anilide synthase in HepG2 and AR42J cells: interrelationships and inhibition by tri-o-tolyl phosphate. Toxicol Appl Pharmacol 1999; 159:134-41. [PMID: 10495777 DOI: 10.1006/taap.1999.8724] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Synthesis of fatty acid ethyl esters (FAEEs), fatty acid methyl esters (FAMEs), and fatty acid anilides (FAAs) in humans and/or experimental animals and in vitro have been reported by us and other investigators. In previous studies, we have demonstrated that fatty acid ethyl ester synthase (FAEES), purified from rat liver microsomes, is structurally and functionally identical to the rat liver microsomal carboxylesterase (pI 6.1) and suggested a role in the conjugation of a variety of xenobiotic alcohols with endogenous fatty acids (B. S. Kaphalia, R. R. Fritz, and G. A. S. Ansari, Chem. Res. Toxicol. 11, 211-218, 1997). However, hepatic FAEES was found to be structurally and functionally different from that of pancreas. Therefore, the present study was undertaken to determine structural and functional interrelationships among the enzyme(s) involved in the synthesis of FAEEs, FAMEs, and FAAs, in HepG2 and AR42J cells using tri-o-tolyl phosphate (TOTP), a specific inhibitor for beta-esterases. Synthesis of FAEEs, FAMEs, and FAAs, studied in the HepG2 cells, was found to be dose- and time-dependent following incubation with methanol, ethanol, or aniline, respectively. Approximately 86-90% inhibition of FAEE, FAME, and FAA synthesizing activities was found in HepG2 cells following exposure to 2.5 microM TOTP. Identical profiles of dose- and time-dependent inhibition of FAEE, FAME, and FAA synthesizing activities by TOTP in HepG2 cells suggest that synthesis of FAEEs, FAMEs, and FAAs is catalyzed by the same enzyme(s). However, FAEE, FAME, and FAA synthesizing activities in AR42J cells could not be inhibited by TOTP under similar experimental conditions. A differential pattern of p-nitrophenyl acetate hydrolyzing activity (a measure of esterase activity) similar to that of fatty acid ester/anilide synthesizing activities was observed in the two cell lines. These results are further substantiated by the presence of approximately 60 kDa (subunit molecular weight) protein in the postnuclear fraction of HepG2 but not in AR42J cells by Western blot analysis using antibodies raised against FAEES, purified from rat liver microsomes or adipose tissue. Therefore, the enzyme responsible for the FAEE, FAME, or FAA synthesizing activities is most probably carboxylesterase in HepG2 cells and is structurally and functionally different than that present in AR42J cells. These studies also indicate the utility of HepG2 and AR42J cell cultures as an alternative to the animal model regarding studies on nonoxidative metabolism of alcohols and amines, in general.
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Affiliation(s)
- B S Kaphalia
- Department of Pathology, University of Texas Medical Branch, Galveston 77555, USA
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