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Zhu L, Jia W, Wan X, Zhuang P, Ma G, Jiao J, Zhang Y. Advancing metabolic networks and mapping updated urinary metabolic fingerprints after exposure to typical carcinogenic heterocyclic aromatic amines. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 319:120936. [PMID: 36572270 DOI: 10.1016/j.envpol.2022.120936] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 11/29/2022] [Accepted: 12/22/2022] [Indexed: 06/17/2023]
Abstract
Heterocyclic aromatic amines (HAAs) were not only present in cooked foods and cigarette smoke, but also measured in airborne particles and diesel-exhaust particles. Typical HAAs have been reported to induce carcinogenicity and metabolic disturbances, but how these hazardous compounds interfere with metabolic networks by regulating metabolic pathways and fingerprinting signature metabolites as biomarkers remains ambiguous. We developed an advanced strategy that adopted chemical isotope labeling ultrahigh-performance liquid chromatography coupled to quadrupole-Orbitrap high-resolution mass spectrometry for urinary nontargeted metabolomics analysis to gain new insight into in vivo physiological responses stimulated by exposure to typical HAAs. Rats were orally administered with a single dose of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) or 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) (1 and 10 mg/kg bw) and their D3-isotopic compounds, respectively, and urine samples were then continuously collected within 36 h. Metabolomics data were acquired and processed by classical multivariate statistical analysis, while urinary metabolites were further identified and characterized according to mass spectrometric fragmentation rules, time- and dose-dependent profiles, and calibration of synthesized standards. We monitored 23 and 37 urinary metabolites as the biotransformation products of PhIP and MeIQx, respectively, and first identified demethylated metabolites of PhIP, tentatively named 2-amino-6-phenylimidazo[4,5-b]pyridine, and dihydroxylation products of classical HAAs as short-term biomarkers of exposure to further unravel the metabolic networks. In addition, our findings revealed that both HAAs significantly disturb histidine metabolism, arginine and proline metabolism, tryptophan metabolism, pyrimidine metabolism, tricarboxylic acid cycle, etc. Furthermore, we found that histamine, methionine, alanine, and 4-guanidinobutanoic acid could be considered potential characteristic biomarkers for the oncogenicity or carcinogenicity of both PhIP and MeIQx and screened their specific key pivotal metabolites. The current metabolomics approach is applicable in mapping updated urinary metabolic fingerprints and identifying potential specific biomarkers for HAAs-induced early tumorigenesis.
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Affiliation(s)
- Li Zhu
- Department of Gastroenterology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, Zhejiang, China; National Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Wei Jia
- Department of Gastroenterology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, Zhejiang, China; National Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Xuzhi Wan
- Department of Gastroenterology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, Zhejiang, China; National Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Pan Zhuang
- Department of Gastroenterology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, Zhejiang, China; National Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Guicen Ma
- Tea Quality and Supervision Testing Center, Ministry of Agriculture and Rural Affairs, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, Zhejiang, China
| | - Jingjing Jiao
- Department of Nutrition, School of Public Health, Department of Endocrinology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, Zhejiang, China
| | - Yu Zhang
- Department of Gastroenterology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, Zhejiang, China; National Engineering Laboratory of Intelligent Food Technology and Equipment, Zhejiang Key Laboratory for Agro-Food Processing, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China.
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Zhang J, Empl MT, Schneider M, Schröder B, Stadnicka-Michalak J, Breves G, Steinberg P, Sturla SJ. Gut microbial transformation of the dietary mutagen MeIQx may reduce exposure levels without altering intestinal transport. Toxicol In Vitro 2019; 59:238-245. [PMID: 30954653 DOI: 10.1016/j.tiv.2019.04.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 03/27/2019] [Accepted: 04/03/2019] [Indexed: 12/13/2022]
Abstract
The mutagen and probable human carcinogen 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) is metabolized in the colon to 9-hydroxyl-2,7-dimethyl-7,9,10,11-tetrahydropyrimido[2',1':2,3]imidazo[4,5-f]quinoxaline (MeIQx-M1) by conjugation with microbially generated acrolein. However, whether this microbiota-controlled process alters systemic exposure and hepatotoxicity of MeIQx remains unclear. The physiological relevance of this microbial transformation on the systemic exposure of MeIQx was investigated using an in vitro-in vivo extrapolation approach. To address whether microbial transformation influences intestinal transport of MeIQx, the intestinal uptake of MeIQx and its metabolite MeIQx-M1 was quantified using Ussing chambers mounted with different intestinal segments from male Fischer 344 rats. Up to 0.4% of both MeIQx and MeIQx-M1 were transported from the mucosal side to the serosal side of intestinal tissue within 90 min, suggesting that the intestinal uptake of both compounds is similar. With the uptake rates of both compounds, physiologically based pharmacokinetic (PBPK) modeling of the fate of MeIQx in the human body including microbial transformation of MeIQx was performed. Results indicate for the first time that high levels of microbe-derived acrolein would be required to significantly reduce systemic exposure of MeIQx in humans. Finally, neither MeIQx nor MeIQx-M1 were cytotoxic towards human liver HepaRG cells at dietary or higher concentrations of MeIQx. In summary, these findings suggest that gut microbial transformation of heterocyclic amines has the potential to influence systemic human exposure to some extent, but may require significant gut microbial production of acrolein and that further investigations are needed to understand physiological levels of acrolein and competing biotransformation pathways.
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Affiliation(s)
- Jianbo Zhang
- Department of Health Sciences and Technology, ETH Zürich, Zürich, Switzerland
| | - Michael T Empl
- Institute for Food Toxicology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Mirjam Schneider
- Department of Health Sciences and Technology, ETH Zürich, Zürich, Switzerland
| | - Bernd Schröder
- Department of Physiology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Julita Stadnicka-Michalak
- Eawag, Dübendorf, Switzerland; School of Architecture, Civil and Environmental Engineering, EPF Lausanne, Switzerland
| | - Gerhard Breves
- Department of Physiology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Pablo Steinberg
- Institute for Food Toxicology, University of Veterinary Medicine Hannover, Hannover, Germany.
| | - Shana J Sturla
- Department of Health Sciences and Technology, ETH Zürich, Zürich, Switzerland.
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3
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Chen YS, Wang R, Dashwood WM, Löhr CV, Williams DE, Ho E, Mertens-Talcott S, Dashwood RH. A miRNA signature for an environmental heterocyclic amine defined by a multi-organ carcinogenicity bioassay in the rat. Arch Toxicol 2017; 91:3415-3425. [PMID: 28289824 PMCID: PMC5836314 DOI: 10.1007/s00204-017-1945-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 02/23/2017] [Indexed: 12/16/2022]
Abstract
Heterocyclic amines (HCAs) produced during high-temperature cooking have been studied extensively in terms of their genotoxic/genetic effects, but recent work has implicated epigenetic mechanisms involving non-coding RNAs. Colon tumors induced in the rat by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) have altered microRNA (miRNA) signatures linked to dysregulated pluripotency factors, such as c-Myc and Krüppel-like factor 4 (KLF4). We tested the hypothesis that dysregulated miRNAs from PhIP-induced colon tumors would provide a "PhIP signature" for use in other target organs obtained from a 1-year carcinogenicity bioassay in the rat. Downstream targets that were corroborated in the rat were then investigated in human cancer datasets. The results confirmed that multiple let-7 family members were downregulated in PhIP-induced skin, colon, lung, small intestine, and Zymbal's gland tumors, and were associated with c-myc and Hmga2 upregulation. PhIP signature miRNAs with the profile mir-21high/mir-126low/mir-29clow/mir-215low/mir-145low were linked to reduced Klf4 levels in rat tumors, and in human pan-cancer and colorectal cancer. It remains to be determined whether this PhIP signature has predictive value, given that more than 20 different genotoxic HCAs are present in the human diet, plus other agents that likely induce or repress many of the same miRNAs. Future studies should define more precisely the miRNA signatures of other HCAs, and their possible value for human risk assessment.
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Affiliation(s)
- Ying-Shiuan Chen
- Center for Epigenetics and Disease Prevention, Texas A&M University College of Medicine, 2121 W Holcombe Blvd., Houston, TX, 77030, USA
| | - Rong Wang
- Linus Pauling Institute, Oregon State University, Corvallis, OR, USA
| | - Wan-Mohaiza Dashwood
- Center for Epigenetics and Disease Prevention, Texas A&M University College of Medicine, 2121 W Holcombe Blvd., Houston, TX, 77030, USA
| | - Christiane V Löhr
- College of Veterinary Medicine, Oregon State University, Corvallis, OR, USA
| | - David E Williams
- Linus Pauling Institute, Oregon State University, Corvallis, OR, USA
- Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR, USA
| | - Emily Ho
- Linus Pauling Institute, Oregon State University, Corvallis, OR, USA
- College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, USA
| | - Susanne Mertens-Talcott
- Department of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Roderick H Dashwood
- Center for Epigenetics and Disease Prevention, Texas A&M University College of Medicine, 2121 W Holcombe Blvd., Houston, TX, 77030, USA.
- Department of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
- Department of Molecular and Cellular Medicine, Texas A&M College of Medicine, College Station, TX, USA.
- Department of Nutrition and Food Science, Texas A&M University, College Station, TX, USA.
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Turner ND, Lloyd SK. Association between red meat consumption and colon cancer: A systematic review of experimental results. Exp Biol Med (Maywood) 2017; 242:813-839. [PMID: 28205448 PMCID: PMC5407540 DOI: 10.1177/1535370217693117] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
A role for red and processed meat in the development of colorectal cancer has been proposed based largely on evidence from observational studies in humans, especially in those populations consuming a westernized diet. Determination of causation specifically by red or processed meat is contingent upon identification of plausible mechanisms that lead to colorectal cancer. We conducted a systematic review of the available evidence to determine the availability of plausible mechanistic data linking red and processed meat consumption to colorectal cancer risk. Forty studies using animal models or cell cultures met specified inclusion criteria, most of which were designed to examine the role of heme iron or heterocyclic amines in relation to colon carcinogenesis. Most studies used levels of meat or meat components well in excess of those found in human diets. Although many of the experiments used semi-purified diets designed to mimic the nutrient loads in current westernized diets, most did not include potential biologically active protective compounds present in whole foods. Because of these limitations in the existing literature, there is currently insufficient evidence to confirm a mechanistic link between the intake of red meat as part of a healthy dietary pattern and colorectal cancer risk. Impact statement Current recommendations to reduce colon cancer include the reduction or elimination of red or processed meats. These recommendations are based on data from epidemiological studies conducted among cultures where meat consumption is elevated and consumption of fruits, vegetables, and whole grains are reduced. This review evaluated experimental data exploring the putative mechanisms whereby red or processed meats may contribute to colon cancer. Most studies used levels of meat or meat-derived compounds that were in excess of those in human diets, even in cultures where meat intake is elevated. Experiments where protective dietary compounds were used to mitigate the extreme levels of meat and meat-derived compounds showed protection against colon cancer, with some essentially negating the impact of meat in the diet. It is essential that better-designed studies be conducted that use relevant concentrations of meat or meat-derived compounds in complex diets representative of the foods consumed by humans.
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Affiliation(s)
- Nancy D Turner
- Nutrition & Food Science Department, Texas A&M University, TX 77843-2253, USA
- Department of Veterinary Pathobiology, Texas A&M University, TX 77843-2253, USA
| | - Shannon K Lloyd
- Nutrition & Food Science Department, Texas A&M University, TX 77843-2253, USA
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Efferth T, Volm M. Multiple resistance to carcinogens and xenobiotics: P-glycoproteins as universal detoxifiers. Arch Toxicol 2017; 91:2515-2538. [DOI: 10.1007/s00204-017-1938-5] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 01/12/2017] [Indexed: 01/08/2023]
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Mimmler M, Peter S, Kraus A, Stroh S, Nikolova T, Seiwert N, Hasselwander S, Neitzel C, Haub J, Monien BH, Nicken P, Steinberg P, Shay JW, Kaina B, Fahrer J. DNA damage response curtails detrimental replication stress and chromosomal instability induced by the dietary carcinogen PhIP. Nucleic Acids Res 2016; 44:10259-10276. [PMID: 27599846 PMCID: PMC5137439 DOI: 10.1093/nar/gkw791] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 07/28/2016] [Accepted: 08/27/2016] [Indexed: 11/13/2022] Open
Abstract
PhIP is an abundant heterocyclic aromatic amine (HCA) and important dietary carcinogen. Following metabolic activation, PhIP causes bulky DNA lesions at the C8-position of guanine. Although C8-PhIP-dG adducts are mutagenic, their interference with the DNA replication machinery and the elicited DNA damage response (DDR) have not yet been studied. Here, we analyzed PhIP-triggered replicative stress and elucidated the role of the apical DDR kinases ATR, ATM and DNA-PKcs in the cellular defense response. First, we demonstrate that PhIP induced C8-PhIP-dG adducts and DNA strand breaks. This stimulated ATR-CHK1 signaling, phosphorylation of histone 2AX and the formation of RPA foci. In proliferating cells, PhIP treatment increased the frequency of stalled replication forks and reduced fork speed. Inhibition of ATR in the presence of PhIP-induced DNA damage strongly promoted the formation of DNA double-strand breaks, activation of the ATM-CHK2 pathway and hyperphosphorylation of RPA. The abrogation of ATR signaling potentiated the cell death response and enhanced chromosomal aberrations after PhIP treatment, while ATM and DNA-PK inhibition had only marginal effects. These results strongly support the notion that ATR plays a key role in the defense against cancer formation induced by PhIP and related HCAs.
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Affiliation(s)
| | - Simon Peter
- Department of Toxicology, University Medical Center, Mainz, Germany
| | - Alexander Kraus
- Department of Toxicology, University Medical Center, Mainz, Germany
| | - Svenja Stroh
- Department of Toxicology, University Medical Center, Mainz, Germany
| | - Teodora Nikolova
- Department of Toxicology, University Medical Center, Mainz, Germany
| | - Nina Seiwert
- Department of Toxicology, University Medical Center, Mainz, Germany
| | | | - Carina Neitzel
- Department of Toxicology, University Medical Center, Mainz, Germany
| | - Jessica Haub
- Department of Toxicology, University Medical Center, Mainz, Germany
| | - Bernhard H Monien
- Department of Food Safety, Federal Institute for Risk Assessment (BfR), Berlin, Germany
- Research Group Genotoxic Food Contaminants, German Institute of Human Nutrition (DIfE), Potsdam-Rehbrücke, Germany
| | - Petra Nicken
- Institute for Food Toxicology and Analytical Chemistry, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Pablo Steinberg
- Institute for Food Toxicology and Analytical Chemistry, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Jerry W Shay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Bernd Kaina
- Department of Toxicology, University Medical Center, Mainz, Germany
| | - Jörg Fahrer
- Department of Toxicology, University Medical Center, Mainz, Germany
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Fekry MI, Engels C, Zhang J, Schwab C, Lacroix C, Sturla SJ, Chassard C. The strict anaerobic gut microbe Eubacterium hallii transforms the carcinogenic dietary heterocyclic amine 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). ENVIRONMENTAL MICROBIOLOGY REPORTS 2016; 8:201-209. [PMID: 26711372 DOI: 10.1111/1758-2229.12369] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 12/15/2015] [Indexed: 06/05/2023]
Abstract
2-Amino-1-methyl-6-phenylimidazo(4,5-b)pyridine (PhIP) is the most abundant food-derived heterocyclic aromatic amine in well-cooked meats and may contribute to the recognized carcinogenicity of processed meats. In this study, a panel of human gut microbes was tested for their ability to convert PhIP to a conjugate PhIP-M1. Eubacterium hallii was newly identified to catalyse the conversion of PhIP to PhIP-M1 with high efficiency. The reaction was shown to involve the metabolism of glycerol to 3-hydroxypropionaldehyde as a key pathway. The proficiency of E. hallii in transforming PhIP in the presence of a complex intestinal microbiota was confirmed using batch fermentations inoculated with effluents from a continuous intestinal fermentation model mimicking human proximal and distal colon microbiota. In batch fermentations inoculated with proximal colon microbiota, PhIP-M1 transformation corresponded to an up to 300-fold increase of E. hallii. In contrast, PhIP transformation of distal colon microbiota was low but increased by 120-fold after supplementation with E. hallii. These findings indicate for the first time the relevance of the abundant commensal strict anaerobe E. hallii in the transformation of a dietary carcinogen that could contribute to its detoxification in the human colon.
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Affiliation(s)
- Mostafa I Fekry
- Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Christina Engels
- Laboratory of Food Biotechnology, Institute of Food, Nutrition and Health, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Jianbo Zhang
- Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Clarissa Schwab
- Laboratory of Food Biotechnology, Institute of Food, Nutrition and Health, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Christophe Lacroix
- Laboratory of Food Biotechnology, Institute of Food, Nutrition and Health, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Shana J Sturla
- Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Christophe Chassard
- Laboratory of Food Biotechnology, Institute of Food, Nutrition and Health, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
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Impact of dextran sulphate sodium-induced colitis on the intestinal transport of the colon carcinogen PhIP. Arch Toxicol 2015; 90:1093-102. [DOI: 10.1007/s00204-015-1546-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 06/03/2015] [Indexed: 12/28/2022]
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9
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Willenberg I, von Elsner L, Steinberg P, Schebb NH. Development of an online-SPE-LC-MS method for the investigation of the intestinal absorption of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PHIP) and its bacterial metabolite PHIP-M1 in a Caco-2 Transwell system. Food Chem 2015; 166:537-543. [DOI: 10.1016/j.foodchem.2014.06.038] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 04/17/2014] [Accepted: 06/08/2014] [Indexed: 10/25/2022]
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Nowak A, Śliżewska K, Błasiak J, Libudzisz Z. The influence of Lactobacillus casei DN 114 001 on the activity of faecal enzymes and genotoxicity of faecal water in the presence of heterocyclic aromatic amines. Anaerobe 2014; 30:129-36. [PMID: 25280921 DOI: 10.1016/j.anaerobe.2014.09.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 09/01/2014] [Accepted: 09/19/2014] [Indexed: 10/24/2022]
Abstract
High activity of bacterial enzymes in human colon and genotoxicity of faecal water (FW) are biomarkers of the harmful action of microbiota. The aim of the present study was to assess the activity of β-glucuronidase and β-glucosidase and the genotoxicity of FW in vitro after incubation with 2-amino-3-methyl-3H-imidazo[4,5-f]quinoline (IQ) or 2-amino-1-methyl-6-phenyl-1H-imidazo[4,5-b]pyridine (PhIP) and probiotic Lactobacillus casei DN 114 001 (Actimel). Our results indicate, that IQ and PhIP greatly increased the activity of faecal enzymes (it was up to four times higher, as measured by spectrophotometric methods) and the genotoxicity of FW (% DNA in the tail was up to 3.2 times higher, as evaluated by the comet assay on Caco-2 cells) in 15 individuals from three age-dependent groups (breast-fed children, adults aged 30-40 years, elderly aged 75-85 years). Lb. casei DN 114 001 decreased the activity of faecal enzymes and the genotoxicity of FW exposed to PhIP and IQ mostly to control values. The activity of faecal enzymes after incubation with IQ was reduced by 71.8% in the FW of children, 37.5% in adults and 64.2% in elderly (β-glucuronidase); as well as by 59.9% in children and 87.9% in elderly (β-glucosidase). For PhIP the reduction was by 59.0% in the FW of children, 50.0% in adults and 81.2% in elderly (β-glucuronidase) and by 20.2% in children, 20.7% in adults and 84.1% in elderly (β-glucosidase). Lb. casei DN 114 001 also decreased the genotoxicity of FW to the greatest extent in adults after incubation with IQ (by 65.4%) and PhIP (by 69.6%) and it was found to correlate positively with the decrease in faecal enzymes activity. In conclusion, Lb. casei DN 114 001 may exert the protective effects against genotoxic and possibly pro-carcinogenic effects of food processing-derived chemicals present in faecal water.
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Affiliation(s)
- Adriana Nowak
- Institute of Fermentation Technology and Microbiology, Department of Biotechnology and Food Sciences, Lodz University of Technology, Wolczanska 171/173, 90-924 Lodz, Poland.
| | - Katarzyna Śliżewska
- Institute of Fermentation Technology and Microbiology, Department of Biotechnology and Food Sciences, Lodz University of Technology, Wolczanska 171/173, 90-924 Lodz, Poland
| | - Janusz Błasiak
- Department of Molecular Genetics, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland
| | - Zdzisława Libudzisz
- Institute of Fermentation Technology and Microbiology, Department of Biotechnology and Food Sciences, Lodz University of Technology, Wolczanska 171/173, 90-924 Lodz, Poland
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