1
|
Zuckerman JT, Jackson AS, Minko IG, Kant M, Jaruga P, Stone MP, Dizdaroglu M, McCullough AK, Lloyd RS. Functional characterization of single nucleotide polymorphic variants of DNA repair enzyme NEIL1 in South Asian populations. DNA Repair (Amst) 2024; 139:103695. [PMID: 38795603 PMCID: PMC11218669 DOI: 10.1016/j.dnarep.2024.103695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 05/07/2024] [Accepted: 05/14/2024] [Indexed: 05/28/2024]
Abstract
The base excision repair (BER) pathway is a precise and versatile mechanism of DNA repair that is initiated by DNA glycosylases. Endonuclease VIII-like 1 (NEIL1) is a bifunctional glycosylase/abasic site (AP) lyase that excises a damaged base and subsequently cleaves the phosphodiester backbone. NEIL1 is able to recognize and hydrolyze a broad range of oxidatively-induced base lesions and substituted ring-fragmented guanines, including aflatoxin-induced 8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxyaflatoxin B1 (AFB1-FapyGua). Due to NEIL1's protective role against these and other pro-mutagenic lesions, it was hypothesized that naturally occurring single nucleotide polymorphic (SNP) variants of NEIL1 could increase human risk for aflatoxin-induced hepatocellular carcinoma (HCC). Given that populations in South Asia experience high levels of dietary aflatoxin exposures and hepatitis B viral infections that induce oxidative stress, investigations on SNP variants of NEIL1 that occur in this region may have clinical implications. In this study, the most common South Asian variants of NEIL1 were expressed, purified, and functionally characterized. All tested variants exhibited activities and substrate specificities similar to wild type (wt)-NEIL1 on high-molecular weight DNA containing an array of oxidatively-induced base lesions. On short oligodeoxynucleotides (17-mers) containing either a site-specific apurinic/apyrimidinic (AP) site, thymine glycol (ThyGly), or AFB1-FapyGua, P206L-NEIL1 was catalytically comparable to wt-NEIL1, while the activities of NEIL1 variants Q67K and T278I on these substrates were ≈2-fold reduced. Variant T103A had a greatly diminished ability to bind to 17-mer DNAs, limiting the subsequent glycosylase and lyase reactions. Consistent with this observation, the rate of excision by T103A on 17-mer oligodeoxynucleotides containing ThyGly or AFB1-FapyGua could not be measured. However, the ability of T103A to excise ThyGly was improved on longer oligodeoxynucleotides (51-mers), with ≈7-fold reduced activity compared to wt-NEIL1. Our studies suggest that NEIL1 variant T103A may present a pathogenic phenotype that is limited in damage recognition, potentially increasing human risk for HCC.
Collapse
Affiliation(s)
- Jamie T Zuckerman
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, United States
| | - Asia Sage Jackson
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, United States; Department of Math & Sciences, Corban University, Salem, OR 97317, United States
| | - Irina G Minko
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, United States
| | - Melis Kant
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, United States
| | - Pawel Jaruga
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, United States
| | - Michael P Stone
- Department of Chemistry, Vanderbilt University, Nashville, TN 37240, United States
| | - Miral Dizdaroglu
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, United States
| | - Amanda K McCullough
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, United States; Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR, 97239, United States
| | - R Stephen Lloyd
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, United States; Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR, 97239, United States.
| |
Collapse
|
2
|
Bellamri M, Yao L, Tomar R, Vartanian V, Rizzo CJ, Stone MP, Groopman JD, Lloyd RS, Turesky RJ. Mass Spectrometry-Based Method to Measure Aflatoxin B 1 DNA Adducts in Formalin-Fixed Paraffin-Embedded Tissues. Chem Res Toxicol 2024; 37:633-642. [PMID: 38498000 PMCID: PMC11279702 DOI: 10.1021/acs.chemrestox.4c00005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Aflatoxin B1 (AFB1) is a potent human liver carcinogen produced by certain molds, particularly Aspergillus flavus and Aspergillus parasiticus, which contaminate peanuts, corn, rice, cottonseed, and ground and tree nuts, principally in warm and humid climates. AFB1 undergoes bioactivation in the liver to produce AFB1-exo-8,9-epoxide, which forms the covalently bound cationic AFB1-N7-guanine (AFB1-N7-Gua) DNA adduct. This adduct is unstable and undergoes base-catalyzed opening of the guanine imidazolium ring to form two ring-opened diastereomeric 8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy-aflatoxin B1 (AFB1-FapyGua) adducts. The AFB1 formamidopyrimidine (Fapy) adducts induce G → T transversion mutations and are likely responsible for the carcinogenic effects of AFB1. Quantitative liquid chromatography-mass spectrometry (LC-MS) methods have shown that AFB1-N7-Gua is eliminated in rodent and human urine, whereas ring-opened AFB1-FapyGua adducts persist in rodent liver. However, fresh frozen biopsy tissues are seldom available for biomonitoring AFB1 DNA adducts in humans, impeding research advances in this potent liver carcinogen. In contrast, formalin-fixed paraffin-embedded (FFPE) specimens used for histopathological analysis are often accessible for molecular studies. However, ensuring nucleic acid quality presents a challenge due to incomplete reversal of formalin-mediated DNA cross-links, which can preclude accurate quantitative measurements of DNA adducts. In this study, employing ion trap or high-resolution accurate Orbitrap mass spectrometry, we demonstrate that ring-opened AFB1-FapyGua adducts formed in AFB1-exposed newborn mice are stable to the formalin fixation and DNA de-cross-linking retrieval processes. The AFB1-FapyGua adducts can be detected at levels comparable to those in a match of fresh frozen liver. Orbitrap MS2 measurements can detect AFB1-FapyGua at a quantification limit of 4.0 adducts per 108 bases when only 0.8 μg of DNA is assayed on the column. Thus, our breakthrough DNA retrieval technology can be adapted to screen for AFB1 DNA adducts in FFPE human liver specimens from cohorts at risk of this potent liver carcinogen.
Collapse
Affiliation(s)
- Medjda Bellamri
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455
| | - Lihua Yao
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455
| | - Rachana Tomar
- Department of Chemistry, Vanderbilt Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee 37235
| | - Vladimir Vartanian
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, Oregon 97239
| | - Carmelo J. Rizzo
- Department of Chemistry, Vanderbilt Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee 37235
| | - Michael P. Stone
- Department of Chemistry, Vanderbilt Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee 37235
| | - John D. Groopman
- Department of Environmental Health and Engineering, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205
| | - R. Stephen Lloyd
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, Oregon 97239
| | - Robert J. Turesky
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455
| |
Collapse
|
3
|
Minko IG, Kellum AH, Stone MP, Lloyd RS. The aflatoxin B 1-induced imidazole ring-opened guanine adduct: High mutagenic potential that is minimally affected by sequence context. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2024; 65 Suppl 1:9-13. [PMID: 37303259 PMCID: PMC10711146 DOI: 10.1002/em.22556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 04/25/2023] [Accepted: 06/08/2023] [Indexed: 06/13/2023]
Abstract
Dietary exposure to aflatoxin B1 (AFB1) is a recognized risk factor for developing hepatocellular carcinoma. The mutational signature of AFB1 is characterized by high-frequency base substitutions, predominantly G>T transversions, in a limited subset of trinucleotide sequences. The 8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxyaflatoxin B1 (AFB1-FapyGua) has been implicated as the primary DNA lesion responsible for AFB1-induced mutations. This study evaluated the mutagenic potential of AFB1-FapyGua in four sequence contexts, including hot- and cold-spot sequences as apparent in the mutational signature. Vectors containing site-specific AFB1-FapyGua lesions were replicated in primate cells and the products of replication were isolated and sequenced. Consistent with the role of AFB1-FapyGua in AFB1-induced mutagenesis, AFB1-FapyGua was highly mutagenic in all four sequence contexts, causing G>T transversions and other base substitutions at frequencies of ~80%-90%. These data suggest that the unique mutational signature of AFB1 is not explained by sequence-dependent fidelity of replication past AFB1-FapyGua lesions.
Collapse
Affiliation(s)
- Irina G. Minko
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd., Portland, OR 97239
| | | | | | - R. Stephen Lloyd
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd., Portland, OR 97239
- Department of Molecular and Medical Genetics, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd., Portland, OR 97239
| |
Collapse
|
4
|
Minko I, Luzadder M, Vartanian V, Rice SM, Nguyen M, Sanchez-Contreras M, Van P, Kennedy S, McCullough A, Lloyd R. Frequencies and spectra of aflatoxin B 1-induced mutations in liver genomes of NEIL1-deficient mice as revealed by duplex sequencing. NAR MOLECULAR MEDICINE 2024; 1:ugae006. [PMID: 38779538 PMCID: PMC11105970 DOI: 10.1093/narmme/ugae006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 04/18/2024] [Accepted: 05/16/2024] [Indexed: 05/25/2024]
Abstract
Increased risk for the development of hepatocellular carcinoma (HCC) is driven by a number of etiological factors including hepatitis viral infection and dietary exposures to foods contaminated with aflatoxin-producing molds. Intracellular metabolic activation of aflatoxin B1 (AFB1) to a reactive epoxide generates highly mutagenic AFB1-Fapy-dG adducts. Previously, we demonstrated that repair of AFB1-Fapy-dG adducts can be initiated by the DNA glycosylase NEIL1 and that male Neil1-/- mice were significantly more susceptible to AFB1-induced HCC relative to wild-type mice. To investigate the mechanisms underlying this enhanced carcinogenesis, WT and Neil1-/- mice were challenged with a single, 4 mg/kg dose of AFB1 and frequencies and spectra of mutations were analyzed in liver DNAs 2.5 months post-injection using duplex sequencing. The analyses of DNAs from AFB1-challenged mice revealed highly elevated mutation frequencies in the nuclear genomes of both males and females, but not the mitochondrial genomes. In both WT and Neil1-/- mice, mutation spectra were highly similar to the AFB1-specific COSMIC signature SBS24. Relative to wild-type, the NEIL1 deficiency increased AFB1-induced mutagenesis with concomitant elevated HCCs in male Neil1-/- mice. Our data establish a critical role of NEIL1 in limiting AFB1-induced mutagenesis and ultimately carcinogenesis.
Collapse
Affiliation(s)
- Irina G Minko
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA
| | - Michael M Luzadder
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA
| | - Vladimir L Vartanian
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA
| | - Sean P M Rice
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA
- School of Public Health, Oregon Health & Science University - Portland State University, Portland, OR, USA
| | - Megan M Nguyen
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | | | - Phu Van
- TwinStrand Biosciences, Inc., Seattle, WA, USA
| | - Scott R Kennedy
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Amanda K McCullough
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA
- Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR, USA
| | - R Stephen Lloyd
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA
- Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR, USA
| |
Collapse
|
5
|
Caipa Garcia AL, Kucab JE, Al-Serori H, Beck RSS, Bellamri M, Turesky RJ, Groopman JD, Francies HE, Garnett MJ, Huch M, Drost J, Zilbauer M, Arlt VM, Phillips DH. Tissue Organoid Cultures Metabolize Dietary Carcinogens Proficiently and Are Effective Models for DNA Adduct Formation. Chem Res Toxicol 2024; 37:234-247. [PMID: 38232180 PMCID: PMC10880098 DOI: 10.1021/acs.chemrestox.3c00255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 12/21/2023] [Accepted: 01/04/2024] [Indexed: 01/19/2024]
Abstract
Human tissue three-dimensional (3D) organoid cultures have the potential to reproduce in vitro the physiological properties and cellular architecture of the organs from which they are derived. The ability of organoid cultures derived from human stomach, liver, kidney, and colon to metabolically activate three dietary carcinogens, aflatoxin B1 (AFB1), aristolochic acid I (AAI), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), was investigated. In each case, the response of a target tissue (liver for AFB1; kidney for AAI; colon for PhIP) was compared with that of a nontarget tissue (gastric). After treatment cell viabilities were measured, DNA damage response (DDR) was determined by Western blotting for p-p53, p21, p-CHK2, and γ-H2AX, and DNA adduct formation was quantified by mass spectrometry. Induction of the key xenobiotic-metabolizing enzymes (XMEs) CYP1A1, CYP1A2, CYP3A4, and NQO1 was assessed by qRT-PCR. We found that organoids from different tissues can activate AAI, AFB1, and PhIP. In some cases, this metabolic potential varied between tissues and between different cultures of the same tissue. Similarly, variations in the levels of expression of XMEs were observed. At comparable levels of cytotoxicity, organoids derived from tissues that are considered targets for these carcinogens had higher levels of adduct formation than a nontarget tissue.
Collapse
Affiliation(s)
- Angela L. Caipa Garcia
- Department
of Analytical, Environmental and Forensic Sciences, School of Cancer
& Pharmaceutical Sciences, King’s
College London, London SE1 9NH, U.K.
| | - Jill E. Kucab
- Department
of Analytical, Environmental and Forensic Sciences, School of Cancer
& Pharmaceutical Sciences, King’s
College London, London SE1 9NH, U.K.
| | - Halh Al-Serori
- Department
of Analytical, Environmental and Forensic Sciences, School of Cancer
& Pharmaceutical Sciences, King’s
College London, London SE1 9NH, U.K.
| | - Rebekah S. S. Beck
- Department
of Analytical, Environmental and Forensic Sciences, School of Cancer
& Pharmaceutical Sciences, King’s
College London, London SE1 9NH, U.K.
| | - Madjda Bellamri
- Department
of Medicinal Chemistry, Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Robert J. Turesky
- Department
of Medicinal Chemistry, Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - John D. Groopman
- Department
of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland 21205, United States
| | | | | | - Meritxell Huch
- Max
Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Jarno Drost
- Princess
Máxima Center for Pediatric Oncology, Oncode Institute, 3584
CS Utrecht, The Netherlands
| | - Matthias Zilbauer
- Department
of Paediatrics, University of Cambridge, Cambridge CB2 0QQ, U.K.
| | - Volker M. Arlt
- Department
of Analytical, Environmental and Forensic Sciences, School of Cancer
& Pharmaceutical Sciences, King’s
College London, London SE1 9NH, U.K.
| | - David H. Phillips
- Department
of Analytical, Environmental and Forensic Sciences, School of Cancer
& Pharmaceutical Sciences, King’s
College London, London SE1 9NH, U.K.
| |
Collapse
|
6
|
Golonka RM, Yeoh BS, Saha P, Tian Y, Chiang JYL, Patterson AD, Gewirtz AT, Joe B, Vijay-Kumar M. Sex Dimorphic Effects of Bile Acid Metabolism in Liver Cancer in Mice. Cell Mol Gastroenterol Hepatol 2024; 17:719-735. [PMID: 38262588 PMCID: PMC10966305 DOI: 10.1016/j.jcmgh.2024.01.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 01/15/2024] [Accepted: 01/16/2024] [Indexed: 01/25/2024]
Abstract
BACKGROUND & AIMS Hepatocellular carcinoma (HCC) is a male-dominant disease, but targeted sex hormone therapies have not been successful. Bile acids are a potential liver carcinogen and are biomolecules with hormone-like effects. A few studies highlight their potential sex dimorphism in physiology and disease. We hypothesized that bile acids could be a potential molecular signature that explains sex disparity in HCC. METHODS & RESULTS We used the farnesoid X receptor knockout (FxrKO) mouse model to study bile acid-dependent HCC. Temporal tracking of circulating bile acids determined more than 80% of FxrKO females developed spontaneous cholemia (ie, serum total bile acids ≥40 μmol/L) as early as 8 weeks old. Opposingly, FxrKO males were highly resistant to cholemia, with ∼23% incidence even when 26 weeks old. However, FxrKO males demonstrated higher levels of deoxycholate than females. Compared with males, FxrKO females had more severe cholestatic liver injury and further aberrancies in bile acid metabolism. Yet, FxrKO females expressed more detoxification transcripts and had greater renal excretion of bile acids. Intervention with CYP7A1 (rate limiting enzyme for bile acid biosynthesis) deficiency or taurine supplementation either completely or partially normalized bile acid levels and liver injury in FxrKO females. Despite higher cholemia prevalence in FxrKO females, their tumor burden was less compared with FxrKO males. An exception to this sex-dimorphic pattern was found in a subset of male and female FxrKO mice born with congenital cholemia due to portosystemic shunt, where both sexes had comparable robust HCC. CONCLUSIONS Our study highlights bile acids as sex-dimorphic metabolites in HCC except in the case of portosystemic shunt.
Collapse
Affiliation(s)
- Rachel M Golonka
- UT Microbiome Consortium, Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio
| | - Beng San Yeoh
- UT Microbiome Consortium, Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio
| | - Piu Saha
- UT Microbiome Consortium, Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio
| | - Yuan Tian
- Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, Pennsylvania
| | - John Y L Chiang
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, Ohio
| | - Andrew D Patterson
- Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, Pennsylvania
| | - Andrew T Gewirtz
- Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences, Georgia State University, Atlanta, Georgia
| | - Bina Joe
- UT Microbiome Consortium, Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio
| | - Matam Vijay-Kumar
- UT Microbiome Consortium, Department of Physiology and Pharmacology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio.
| |
Collapse
|
7
|
Gerdemann A, Cramer B, Degen GH, Veerkamp J, Günther G, Albrecht W, Behrens M, Esselen M, Ghallab A, Hengstler JG, Humpf HU. Comparative metabolism of aflatoxin B 1 in mouse, rat and human primary hepatocytes using HPLC-MS/MS. Arch Toxicol 2023; 97:3179-3196. [PMID: 37794256 PMCID: PMC10567917 DOI: 10.1007/s00204-023-03607-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 09/14/2023] [Indexed: 10/06/2023]
Abstract
Aflatoxin B1 (AFB1) is a highly hepatotoxic and carcinogenic mycotoxin produced by Aspergillus species. The compound is mainly metabolized in the liver and its metabolism varies between species. The present study quantified relevant AFB1- metabolites formed by mouse, rat, and human primary hepatocytes after treatment with 1 µM and 10 µM AFB1. The use of liquid chromatographic separation coupled with tandem mass spectrometric detection enabled the selective and sensitive determination of phase I and phase II metabolites of AFB1 over incubation times of up to 24 h. The binding of AFB1 to macromolecules was also considered. The fastest metabolism of AFB1 was observed in mouse hepatocytes which formed aflatoxin P1 as a major metabolite and also its glucuronidated form, while AFP1 occurred only in traces in the other species. Aflatoxin M1 was formed in all species and was, together with aflatoxin Q1 and aflatoxicol, the main metabolite in human cells. Effective epoxidation led to high amounts of DNA adducts already 30 min post-treatment, especially in rat hepatocytes. Lower levels of DNA adducts and fast DNA repair were found in mouse hepatocytes. Also, protein adducts arising from reactive intermediates were formed rapidly in all three species. Detoxification via glutathione conjugation and subsequent formation of the N-acetylcysteine derivative appeared to be similar in mice and in rats and strongly differed from human hepatocytes which did not form these metabolites at all. The use of qualitative reference material of a multitude of metabolites and the comparison of hepatocyte metabolism in three species using advanced methods enabled considerations on toxification and detoxification mechanisms of AFB1. In addition to glutathione conjugation, phase I metabolism is strongly involved in the detoxification of AFB1.
Collapse
Affiliation(s)
- Andrea Gerdemann
- Institute of Food Chemistry, University of Münster, Corrensstraße 45, 48149 Münster, Germany
| | - Benedikt Cramer
- Institute of Food Chemistry, University of Münster, Corrensstraße 45, 48149 Münster, Germany
| | - Gisela H. Degen
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Ardeystraße 67, 44139 Dortmund, Germany
| | - Jannik Veerkamp
- Institute of Food Chemistry, University of Münster, Corrensstraße 45, 48149 Münster, Germany
| | - Georgia Günther
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Ardeystraße 67, 44139 Dortmund, Germany
| | - Wiebke Albrecht
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Ardeystraße 67, 44139 Dortmund, Germany
| | - Matthias Behrens
- Institute of Food Chemistry, University of Münster, Corrensstraße 45, 48149 Münster, Germany
| | - Melanie Esselen
- Institute of Food Chemistry, University of Münster, Corrensstraße 45, 48149 Münster, Germany
| | - Ahmed Ghallab
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Ardeystraße 67, 44139 Dortmund, Germany
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, South Valley University, Qena, 83523 Egypt
| | - Jan G. Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Ardeystraße 67, 44139 Dortmund, Germany
| | - Hans-Ulrich Humpf
- Institute of Food Chemistry, University of Münster, Corrensstraße 45, 48149 Münster, Germany
| |
Collapse
|
8
|
Stanfill SB, Hecht SS, Joerger AC, González PJ, Maia LB, Rivas MG, Moura JJG, Gupta AK, Le Brun NE, Crack JC, Hainaut P, Sparacino-Watkins C, Tyx RE, Pillai SD, Zaatari GS, Henley SJ, Blount BC, Watson CH, Kaina B, Mehrotra R. From cultivation to cancer: formation of N-nitrosamines and other carcinogens in smokeless tobacco and their mutagenic implications. Crit Rev Toxicol 2023; 53:658-701. [PMID: 38050998 DOI: 10.1080/10408444.2023.2264327] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 09/20/2023] [Indexed: 12/07/2023]
Abstract
Tobacco use is a major cause of preventable morbidity and mortality globally. Tobacco products, including smokeless tobacco (ST), generally contain tobacco-specific N-nitrosamines (TSNAs), such as N'-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-butanone (NNK), which are potent carcinogens that cause mutations in critical genes in human DNA. This review covers the series of biochemical and chemical transformations, related to TSNAs, leading from tobacco cultivation to cancer initiation. A key aim of this review is to provide a greater understanding of TSNAs: their precursors, the microbial and chemical mechanisms that contribute to their formation in ST, their mutagenicity leading to cancer due to ST use, and potential means of lowering TSNA levels in tobacco products. TSNAs are not present in harvested tobacco but can form due to nitrosating agents reacting with tobacco alkaloids present in tobacco during certain types of curing. TSNAs can also form during or following ST production when certain microorganisms perform nitrate metabolism, with dissimilatory nitrate reductases converting nitrate to nitrite that is then released into tobacco and reacts chemically with tobacco alkaloids. When ST usage occurs, TSNAs are absorbed and metabolized to reactive compounds that form DNA adducts leading to mutations in critical target genes, including the RAS oncogenes and the p53 tumor suppressor gene. DNA repair mechanisms remove most adducts induced by carcinogens, thus preventing many but not all mutations. Lastly, because TSNAs and other agents cause cancer, previously documented strategies for lowering their levels in ST products are discussed, including using tobacco with lower nornicotine levels, pasteurization and other means of eliminating microorganisms, omitting fermentation and fire-curing, refrigerating ST products, and including nitrite scavenging chemicals as ST ingredients.
Collapse
Affiliation(s)
- Stephen B Stanfill
- Tobacco and Volatiles Branch, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Stephen S Hecht
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| | - Andreas C Joerger
- Structural Genomics Consortium (SGC), Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Pablo J González
- Department of Physics, Universidad Nacional Litoral, and CONICET, Santa Fe, Argentina
| | - Luisa B Maia
- Department of Chemistry, LAQV, REQUIMTE, NOVA School of Science and Technology (FCT NOVA), Caparica, Portugal
| | - Maria G Rivas
- Department of Physics, Universidad Nacional Litoral, and CONICET, Santa Fe, Argentina
| | - José J G Moura
- Department of Chemistry, LAQV, REQUIMTE, NOVA School of Science and Technology (FCT NOVA), Caparica, Portugal
| | | | - Nick E Le Brun
- School of Chemistry, Centre for Molecular and Structural Biochemistry, University of East Anglia, Norwich, UK
| | - Jason C Crack
- School of Chemistry, Centre for Molecular and Structural Biochemistry, University of East Anglia, Norwich, UK
| | - Pierre Hainaut
- Institute for Advanced Biosciences, Grenoble Alpes University, Grenoble, France
| | - Courtney Sparacino-Watkins
- University of Pittsburgh, School of Medicine, Division of Pulmonary Allergy and Critical Care Medicine, Vascular Medicine Institute, PA, USA
| | - Robert E Tyx
- Tobacco and Volatiles Branch, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Suresh D Pillai
- Department of Food Science & Technology, National Center for Electron Beam Research, Texas A&M University, College Station, TX, USA
| | - Ghazi S Zaatari
- Department of Pathology and Laboratory Medicine, American University of Beirut, Beirut, Lebanon
| | - S Jane Henley
- Division of Cancer Prevention and Control, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Benjamin C Blount
- Tobacco and Volatiles Branch, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Clifford H Watson
- Tobacco and Volatiles Branch, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Bernd Kaina
- Institute of Toxicology, University Medical Center, Mainz, Germany
| | - Ravi Mehrotra
- Centre for Health, Innovation and Policy Foundation, Noida, India
| |
Collapse
|
9
|
Wang Y, Jiang L, Zhang Y, Ran R, Meng X, Liu S. Research advances in the degradation of aflatoxin by lactic acid bacteria. J Venom Anim Toxins Incl Trop Dis 2023; 29:e20230029. [PMID: 37901116 PMCID: PMC10601132 DOI: 10.1590/1678-9199-jvatitd-2023-0029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 09/20/2023] [Indexed: 10/31/2023] Open
Abstract
Aflatoxins are toxic secondary metabolites that often contaminate food and animal feed, causing huge economic losses and serious health hazards. Aflatoxin contamination has become a major concern worldwide. Biological methods have been used to reduce aflatoxins in food and feed by inhibiting toxin production and detoxification. Among biological methods, lactic acid bacteria are of significant interest because of their safety, efficiency, and environmental friendliness. This study aimed to review the mechanisms by which lactic acid bacteria degrade aflatoxins and the factors that influence their degradation efficiency, including the action of the lactic acid bacteria themselves (cell wall adsorption) and the antifungal metabolites produced by the lactic acid bacteria. The current applications of lactic acid bacteria to food and feed were also reviewed. This comprehensive analysis provided insight into the binding mechanisms between lactic acid bacteria and aflatoxins, facilitating the practical applications of lactic acid bacteria to food and agriculture.
Collapse
Affiliation(s)
- Yuxi Wang
- Institute of Public Health, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Lishi Jiang
- Institute of Public Health, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ying Zhang
- Institute of Public Health, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ran Ran
- School of Light Industry and Materials, Chengdu Textile College, Chengdu, China
| | - Xiao Meng
- Institute of Public Health, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Shukun Liu
- Institute of Public Health, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| |
Collapse
|
10
|
De Graeve M, Van de Walle E, Van Hecke T, De Smet S, Vanhaecke L, Hemeryck LY. Exploration and optimization of extraction, analysis and data normalization strategies for mass spectrometry-based DNA adductome mapping and modeling. Anal Chim Acta 2023; 1274:341578. [PMID: 37455087 DOI: 10.1016/j.aca.2023.341578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 06/23/2023] [Accepted: 06/29/2023] [Indexed: 07/18/2023]
Abstract
Although interest in characterizing DNA damage by means of DNA adductomics has substantially grown, the field of DNA adductomics is still in its infancy, with room for optimization of methods for sample analysis, data processing and DNA adduct identification. In this context, the first objective of this study was to evaluate the use of hydrophilic interaction (HILIC) vs. reversed phase liquid chromatography (RPLC) coupled to high resolution mass spectrometry (HRMS) and thermal acidic vs. enzymatic hydrolysis of DNA followed by DNA adduct purification and enrichment using solid-phase extraction (SPE) or fraction collection for DNA adductome mapping. The second objective was to assess the use of total ion count (TIC) and median intensity (MedI) normalization compared to QC (quality control), iQC (internal QC) and quality control-based robust locally estimated scatterplot smoothing (LOESS) signal correction (QC-RLSC) normalization for processing of the acquired data. The results demonstrate that HILIC compared to RPLC allowed better modeling of the tentative DNA adductome, particularly in combination with thermal acidic hydrolysis and SPE (more valid models, with an average Q2(Y) and R2(Y) of 0.930 and 0.998, respectively). Regarding the need for data normalization and the management of (limited) system instability and signal drift, QC normalization outperformed TIC, MedI, iQC and LOESS normalization. As such, QC normalization can be put forward as the default data normalization strategy. In case of momentous signal drift and/or batch effects however, comparison to other normalization strategies (like e.g. LOESS) is recommended. In future work, further optimization of DNA adductomics may be achieved by merging of HILIC and RPLC datasets and/or application of 2D-LC, as well as the inclusion of Schiff base stabilization and/or fraction collection in the thermal acidic hydrolysis-SPE sample preparation workflow.
Collapse
Affiliation(s)
- Marilyn De Graeve
- Laboratory of Integrative Metabolomics, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium.
| | - Emma Van de Walle
- Laboratory of Integrative Metabolomics, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium.
| | - Thomas Van Hecke
- Laboratory for Animal Nutrition and Animal Product Quality, Faculty of Bioscience Engineering, Ghent University, Coupure Links, 653, B-9000, Ghent, Belgium.
| | - Stefaan De Smet
- Laboratory for Animal Nutrition and Animal Product Quality, Faculty of Bioscience Engineering, Ghent University, Coupure Links, 653, B-9000, Ghent, Belgium.
| | - Lynn Vanhaecke
- Laboratory of Integrative Metabolomics, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium; Institute for Global Food Security, School of Biological Sciences, Queen's University, University Road, Belfast, United Kingdom.
| | - Lieselot Y Hemeryck
- Laboratory of Integrative Metabolomics, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium.
| |
Collapse
|
11
|
Zuckerman JT, Minko IG, Kant M, Jaruga P, Stone MP, Dizdaroglu M, McCullough AK, Lloyd RS. Functional analyses of single nucleotide polymorphic variants of the DNA glycosylase NEIL1 in sub-Saharan African populations. DNA Repair (Amst) 2023; 129:103544. [PMID: 37517321 PMCID: PMC10546947 DOI: 10.1016/j.dnarep.2023.103544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 07/07/2023] [Accepted: 07/18/2023] [Indexed: 08/01/2023]
Abstract
Nei-like glycosylase 1 (NEIL1) is a DNA repair enzyme that initiates the base excision repair (BER) pathway to cleanse the human genome of damage. The substrate specificity of NEIL1 includes several common base modifications formed under oxidative stress conditions, as well as the imidazole ring open adducts that are induced by alkylating agents following initial modification at N7 guanine. An example of the latter is the persistent and mutagenic 8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxyaflatoxin B1 (AFB1-FapyGua) adduct, resulting from the alkylating agent aflatoxin B1 (AFB1) exo-8-9-epoxide. Naturally occurring single nucleotide polymorphic (SNP) variants of NEIL1 are hypothesized to be associated with an increased risk for development of early-onset hepatocellular carcinoma (HCC), especially in environments with high exposures to aflatoxins and chronic inflammation from viral infections and alcohol consumption. Given that AFB1 exposures and hepatitis B viral (HBV) infections represent a major problem in the developing countries of sub-Saharan Africa, it is pertinent to study SNP NEIL1 variants that are present in this geographic region. In this investigation, we characterized the three most common NEIL1 variants found in this region: P321A, R323G, and I182M. Biochemical analyses were conducted to determine the proficiencies of these variants in initiating the repair of DNA lesions. Our data show that damage recognition and excision activities of P321A and R323G were near that of wild-type (WT) NEIL1 for both thymine glycol (ThyGly) and AFB1-FapyGua. The substrate specificities of these variants with respect to various oxidatively-induced base lesions were also similar to that of WT. In contrast, the I182M variant was unstable, such that it precipitated under a variety of conditions and underwent rapid inactivation at a biologically relevant temperature, with partial stabilization being observed in the presence of undamaged DNA. This study provides insight regarding the potential increased risk for early-onset HCC in human populations carrying the NEIL1 I182M variant.
Collapse
Affiliation(s)
- Jamie T Zuckerman
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, United States
| | - Irina G Minko
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, United States
| | - Melis Kant
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, United States
| | - Pawel Jaruga
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, United States
| | - Michael P Stone
- Department of Chemistry, Vanderbilt University, Nashville, TN 37240, United States
| | - Miral Dizdaroglu
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, United States
| | - Amanda K McCullough
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, United States; Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR 97239, United States
| | - R Stephen Lloyd
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, United States; Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR 97239, United States.
| |
Collapse
|
12
|
Jaruga P, Tomar R, Kant M, Vartanian V, Sexton B, Rizzo CJ, Turesky RJ, Stone MP, Lloyd RS, Dizdaroglu M. Synthesis and Characterization of 15N 5-Labeled Aflatoxin B 1-Formamidopyrimidines and Aflatoxin B 1-N7-Guanine from a Partial Double-Stranded Oligodeoxynucleotide as Internal Standards for Mass Spectrometric Measurements. ACS OMEGA 2023; 8:14841-14854. [PMID: 37125130 PMCID: PMC10134230 DOI: 10.1021/acsomega.3c01328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 03/20/2023] [Indexed: 05/03/2023]
Abstract
Aflatoxin B1 (AFB1) exposure through contaminated food is a primary contributor to hepatocellular carcinogenesis worldwide. Hepatitis B viral infections in livers dramatically increase the carcinogenic potency of AFB1 exposures. Liver cytochrome P450 oxidizes AFB1 to the epoxide, which in turn reacts with N7-guanine in DNA, producing the cationic trans-8,9-dihydro-8-(N7-guanyl)-9-hydroxyaflatoxin B1 adduct (AFB1-N7-Gua). The opening of the imidazole ring of AFB1-N7-Gua under physiological conditions causes the formation of the cis- and trans-diastereomers of 8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxyaflatoxin B1 (AFB1-FapyGua). These adducts primarily lead to G → T mutations, with AFB1-FapyGua being significantly more mutagenic than AFB1-N7-Gua. The unequivocal identification and accurate quantification of these AFB1-Gua adducts as biomarkers are essential for a fundamental understanding and prevention of AFB1-induced hepatocellular carcinogenesis. Among a variety of analytical techniques used for this purpose, liquid chromatography-tandem mass spectrometry, with the use of the stable isotope-labeled analogues of AFB1-FapyGua and AFB1-N7-Gua as internal standards, provides the greatest accuracy and sensitivity. cis-AFB1-FapyGua-15N5, trans-AFB1-FapyGua-15N5, and AFB1-N7-Gua-15N5 have been synthesized and used successfully as internal standards. However, the availability of these standards from either academic institutions or commercial sources ceased to exist. Thus, quantitative genomic data regarding AFB1-induced DNA damage in animal models and humans remain challenging to obtain. Previously, AFB1-N7-Gua-15N5 was prepared by reacting AFB1-exo-8,9-epoxide with the uniformly 15N5-labeled DNA isolated from algae grown in a pure 15N-environment, followed by alkali treatment, resulting in the conversion of AFB1-N7-Gua-15N5 to AFB1-FapyGua-15N5. In the present work, we used a different and simpler approach to synthesize cis-AFB1-FapyGua-15N5, trans-AFB1-FapyGua-15N5, and AFB1-N7-Gua-15N5 from a partial double-stranded 11-mer Gua-15N5-labeled oligodeoxynucleotide, followed by isolation and purification. We also show the validation of these 15N5-labeled standards for the measurement of cis-AFB1-FapyGua, trans-AFB1-FapyGua, and AFB1-N7-Gua in DNA of livers of AFB1-treated mice.
Collapse
Affiliation(s)
- Pawel Jaruga
- Biomolecular
Measurement Division, National Institute
of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Rachana Tomar
- Department
of Chemistry, Vanderbilt Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Melis Kant
- Biomolecular
Measurement Division, National Institute
of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Vladimir Vartanian
- Oregon
Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, Oregon 97239, United States
| | - Benjamin Sexton
- Department
of Chemistry, Vanderbilt Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Carmelo J. Rizzo
- Department
of Chemistry, Vanderbilt Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Robert J. Turesky
- Masonic
Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Michael P. Stone
- Department
of Chemistry, Vanderbilt Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - R. Stephen Lloyd
- Oregon
Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, Oregon 97239, United States
| | - Miral Dizdaroglu
- Biomolecular
Measurement Division, National Institute
of Standards and Technology, Gaithersburg, Maryland 20899, United States
| |
Collapse
|
13
|
Wu X, Meng W, Duan C, Cao J, Wei Y, Cui X, Zhu D, Lv P, Shen H, Zhang X. AFG1-induced TNF-α-mediated inflammation enhances gastric epithelial cell injury via CYP2E1. Food Chem Toxicol 2023; 176:113756. [PMID: 36997055 DOI: 10.1016/j.fct.2023.113756] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 03/05/2023] [Accepted: 03/27/2023] [Indexed: 03/30/2023]
Abstract
Aflatoxin G1 (AFG1), a member of the aflatoxin family with cytotoxic and carcinogenic properties, is one of the most common mycotoxins occurring in various agricultural products, animal feed, and human foods and drinks worldwide. Epithelial cells in the gastrointestinal tract are the first line of defense against ingested mycotoxins. However, the toxicity of AFG1 to gastric epithelial cells (GECs) remains unclear. In this study, we explored whether and how AFG1-induced gastric inflammation regulates cytochrome P450 to contribute to DNA damage in GECs. Oral administration of AFG1 induced gastric inflammation and DNA damage in mouse GECs associated with P450 2E1 (CYP2E1) upregulation. Treatment with the soluble TNF-α receptor sTNFR:Fc inhibited AFG1-induced gastric inflammation, and reversed CYP2E1 upregulation and DNA damage in mouse GECs. TNF-α-mediated inflammation plays an important role in AFG1-induced gastric cell damage. Using the human gastric cell line GES-1, AFG1 upregulated CYP2E1 through NF-κB, causing oxidative DNA damage in vitro. The cells were also treated with TNF-α and AFG1 to mimic AFG1-induced TNF-α-mediated inflammation. TNF-α activated the NF-κB/CYP2E1 pathway to promote AFG1 activation, which enhanced DNA cellular damage in vitro. In conclusion, AFG1 ingestion induces TNF-α-mediated gastric inflammation, which upregulates CYP2E1 to promote AFG1-induced DNA damage in GECs.
Collapse
|
14
|
Zhao Y, Chen D, Duan H, Li P, Wu W, Wang X, Poapolathep A, Poapolathep S, Logrieco AF, Pascale M, Wang C, Zhang Z. Sample preparation and mass spectrometry for determining mycotoxins, hazardous fungi, and their metabolites in the environment, food, and healthcare. Trends Analyt Chem 2023. [DOI: 10.1016/j.trac.2023.116962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
|
15
|
Cooke MS, Chang YJ, Chen YR, Hu CW, Chao MR. Nucleic acid adductomics - The next generation of adductomics towards assessing environmental health risks. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 856:159192. [PMID: 36195140 DOI: 10.1016/j.scitotenv.2022.159192] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 09/07/2022] [Accepted: 09/29/2022] [Indexed: 06/16/2023]
Abstract
This Discussion article aims to explore the potential for a new generation of assay to emerge from cellular and urinary DNA adductomics which brings together DNA-RNA- and, to some extent, protein adductomics, to better understand the role of the exposome in environmental health. Components of the exposome have been linked to an increased risk of various, major diseases, and to identify the precise nature, and size, of risk, in this complex mixture of exposures, powerful tools are needed. Modification of nucleic acids (NA) is a key consequence of environmental exposures, and a goal of cellular DNA adductomics is to evaluate the totality of DNA modifications in the genome, on the basis that this will be most informative. Consequently, an approach which encompasses modifications of all nucleic acids (NA) would be potentially yet more informative. This article focuses on NA adductomics, which brings together the assessment of both DNA and RNA modifications, including modified (2'-deoxy)ribonucleosides (2'-dN/rN), modified nucleobases (nB), plus: DNA-DNA, RNA-RNA, DNA-RNA, DNA-protein, and RNA-protein crosslinks (DDCL, RRCL, DRCL, DPCL, and RPCL, respectively). We discuss the need for NA adductomics, plus the pros and cons of cellular vs. urinary NA adductomics, and present some evidence for the feasibility of this approach. We propose that NA adductomics provides a more comprehensive approach to the study of nucleic acid modifications, which will facilitate a range of advances, including the identification of novel, unexpected modifications e.g., RNA-RNA, and DNA-RNA crosslinks; key modifications associated with mutagenesis; agent-specific mechanisms; and adductome signatures of key environmental agents, leading to the dissection of the exposome, and its role in human health/disease, across the life course.
Collapse
Affiliation(s)
- Marcus S Cooke
- Oxidative Stress Group, Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, FL 33620, USA.
| | - Yuan-Jhe Chang
- Department of Occupational Safety and Health, Chung Shan Medical University, Taichung 402, Taiwan
| | - Yet-Ran Chen
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Chiung-Wen Hu
- Department of Public Health, Chung Shan Medical University, Taichung 402, Taiwan.
| | - Mu-Rong Chao
- Department of Occupational Safety and Health, Chung Shan Medical University, Taichung 402, Taiwan; Department of Occupational Medicine, Chung Shan Medical University Hospital, Taichung 402, Taiwan.
| |
Collapse
|
16
|
Kobets T, Smith BPC, Williams GM. Food-Borne Chemical Carcinogens and the Evidence for Human Cancer Risk. Foods 2022; 11:foods11182828. [PMID: 36140952 PMCID: PMC9497933 DOI: 10.3390/foods11182828] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 09/07/2022] [Accepted: 09/08/2022] [Indexed: 11/16/2022] Open
Abstract
Commonly consumed foods and beverages can contain chemicals with reported carcinogenic activity in rodent models. Moreover, exposures to some of these substances have been associated with increased cancer risks in humans. Food-borne carcinogens span a range of chemical classes and can arise from natural or anthropogenic sources, as well as form endogenously. Important considerations include the mechanism(s) of action (MoA), their relevance to human biology, and the level of exposure in diet. The MoAs of carcinogens have been classified as either DNA-reactive (genotoxic), involving covalent reaction with nuclear DNA, or epigenetic, involving molecular and cellular effects other than DNA reactivity. Carcinogens are generally present in food at low levels, resulting in low daily intakes, although there are some exceptions. Carcinogens of the DNA-reactive type produce effects at lower dosages than epigenetic carcinogens. Several food-related DNA-reactive carcinogens, including aflatoxins, aristolochic acid, benzene, benzo[a]pyrene and ethylene oxide, are recognized by the International Agency for Research on Cancer (IARC) as causes of human cancer. Of the epigenetic type, the only carcinogen considered to be associated with increased cancer in humans, although not from low-level food exposure, is dioxin (TCDD). Thus, DNA-reactive carcinogens in food represent a much greater risk than epigenetic carcinogens.
Collapse
Affiliation(s)
- Tetyana Kobets
- Department of Pathology, Microbiology and Immunology, New York Medical College, Valhalla, NY 10595, USA
- Correspondence: ; Tel.: +1-914-594-3105; Fax: +1-914-594-4163
| | - Benjamin P. C. Smith
- Future Ready Food Safety Hub, Nanyang Technological University, Singapore 639798, Singapore
| | - Gary M. Williams
- Department of Pathology, Microbiology and Immunology, New York Medical College, Valhalla, NY 10595, USA
| |
Collapse
|
17
|
Zhou M, Wang DO, Li W, Zheng J. RNA adduction derived from electrophilic species in vitro and in vivo. Chem Biol Interact 2022; 351:109748. [PMID: 34801539 DOI: 10.1016/j.cbi.2021.109748] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 10/30/2021] [Accepted: 11/10/2021] [Indexed: 11/03/2022]
Abstract
RNA molecules are essential for cell function by not only serving as genetic materials, but also providing cells with structural support and catalytic functions. Due to nucleophilicity of nucleobases, RNA molecules can react with electrophilic species thus to be "adducted". The electron-deficient agents potentially inducing adduction exist in a variety of natural sources including metabolic products of biomolecules. Although evident and readily detected in human tissue, RNA adduction remains poorly understood for their physiological and pathological function. In this article, we review a collection of exogenous and endogenous molecular species that participate in RNA adduction and elaborates on the chemical nature of their RNA adduction sites. Furthermore, we provide perspectives on the potential of RNA adducts as biomarkers of environmental insults. Finally, we project future investigations that are necessary for understanding the mechanisms of cellular toxicity of RNA adduction.
Collapse
Affiliation(s)
- Mengyue Zhou
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Provincial Key Laboratory of Pharmaceutics, Guizhou Medical University, Guiyang, Guizhou, 550025, PR China
| | - Dan Ohtan Wang
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, 110016, PR China; Center for Biosystems Dynamics Research, RIKEN, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan
| | - Weiwei Li
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Provincial Key Laboratory of Pharmaceutics, Guizhou Medical University, Guiyang, Guizhou, 550025, PR China
| | - Jiang Zheng
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Provincial Key Laboratory of Pharmaceutics, Guizhou Medical University, Guiyang, Guizhou, 550025, PR China; Key Laboratory of Environmental Pollution, Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, Guizhou, 550025, PR China; Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, 110016, PR China.
| |
Collapse
|
18
|
Cheraghi Shahi S, Dadmehr M, Korouzhdehi B, Tavassoli A. A novel colorimetric biosensor for sensitive detection of aflatoxin mediated by bacterial enzymatic reaction in saffron samples. NANOTECHNOLOGY 2021; 32:505503. [PMID: 34488207 DOI: 10.1088/1361-6528/ac23f7] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Accepted: 09/06/2021] [Indexed: 05/28/2023]
Abstract
Aflatoxin is regarded as the potent carcinogenic agent which is secreted from fungi and present in some food products. So far, many detection methods have been developed to determine the trace amounts of aflatoxin in foods. In the present study a colorimetric competitive assay for detection of aflatoxin B1 (AFB1) has been developed based on interaction of gelatin functionalized gold nanoparticles (AuNPs@gelatin) in specific enzymatic reaction. Bacterial supernatant containing gelatinase enzyme were used as the substrate that could digest the coated gelatin on the surface of AuNPs and following in the presence of NaCl medium ingredient resulted to color change of AuNPs colloidal solution from red to purple. It was observed that with addition of aflatoxin to the bacterial supernatant, aflatoxin could interfere in aggregation of AuNPs and inhibited the process which subsequently prevent the expected color change induced by AuNPs aggregation. The supernatant containing AuNPs were investigated to analyze their induced surface plasmon resonance spectra through UV-visible spectroscopy. The absorption values were directly proportional with the applied AFB1 concentration. The experiment conditions including incubation time, AuNPs concentration and pH were investigated. The obtained results showed that through this approach we could detect the AFB1 in a linear range from 10 to 140 pg ml-1, with detection limit of 4 pg ml-1. Real sample assay in saffron samples showed recoveries percentage of 92.4%-95.3%. The applied approach proposed simple, cost effective and specific method for detection of AFB1 toxin in food samples.
Collapse
Affiliation(s)
| | - Mehdi Dadmehr
- Department of Biology, Payame Noor University, Tehran, Iran
| | - Behnaz Korouzhdehi
- Department of Biotechnology, College of Agriculture & Natural Resources, University of Tehran, Karaj, Iran
| | | |
Collapse
|
19
|
Lanier C, Garon D, Heutte N, Kientz V, André V. Comparative Toxigenicity and Associated Mutagenicity of Aspergillus fumigatus and Aspergillus flavus Group Isolates Collected from the Agricultural Environment. Toxins (Basel) 2020; 12:E458. [PMID: 32709162 PMCID: PMC7404940 DOI: 10.3390/toxins12070458] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 12/30/2022] Open
Abstract
The mutagenic patterns of A. flavus, A. parasiticus and A. fumigatus extracts were evaluated. These strains of toxigenic Aspergillus were collected from the agricultural environment. The Ames test was performed on Salmonella typhimurium strains TA98, TA100 and TA102, without and with S9mix (exogenous metabolic activation system). These data were compared with the mutagenicity of the corresponding pure mycotoxins tested alone or in reconstituted mixtures with equivalent concentrations, in order to investigate the potential interactions between these molecules and/or other natural metabolites. At least 3 mechanisms are involved in the mutagenic response of these aflatoxins: firstly, the formation of AFB1-8,9-epoxide upon addition of S9mix, secondly the likely formation of oxidative damage as indicated by significant responses in TA102, and thirdly, a direct mutagenicity observed for higher doses of some extracts or associated mycotoxins, which does not therefore involve exogenously activated intermediates. Besides the identified mycotoxins (AFB1, AFB2 and AFM1), additional "natural" compounds contribute to the global mutagenicity of the extracts. On the other hand, AFB2 and AFM1 modulate negatively the mutagenicity of AFB1 when mixed in binary or tertiary mixtures. Thus, the evaluation of the mutagenicity of "natural" mixtures is an integrated parameter that better reflects the potential impact of exposure to toxigenic Aspergilli.
Collapse
Affiliation(s)
- Caroline Lanier
- Faculty of Health, Normandie University, UNICAEN, Centre F. Baclesse, UR ABTE EA4651, 14000 Caen, France; (C.L.); (D.G.)
| | - David Garon
- Faculty of Health, Normandie University, UNICAEN, Centre F. Baclesse, UR ABTE EA4651, 14000 Caen, France; (C.L.); (D.G.)
| | - Natacha Heutte
- Faculty of Sports, Normandie University, UNIROUEN, CETAPS EA3832, 76821 Mont Saint Aignan CEDEX, France;
| | - Valérie Kientz
- Laboratoire LABEO, Route de Rosel, 14280 Saint-Contest, France;
| | - Véronique André
- Faculty of Health, Normandie University, UNICAEN, Centre F. Baclesse, UR ABTE EA4651, 14000 Caen, France; (C.L.); (D.G.)
| |
Collapse
|
20
|
Hernandez-Castillo C, Termini J, Shuck S. DNA Adducts as Biomarkers To Predict, Prevent, and Diagnose Disease-Application of Analytical Chemistry to Clinical Investigations. Chem Res Toxicol 2020; 33:286-307. [PMID: 31638384 DOI: 10.1021/acs.chemrestox.9b00295] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Characterization of the chemistry, structure, formation, and metabolism of DNA adducts has been one of the most significant contributions to the field of chemical toxicology. This work provides the foundation to develop analytical methods to measure DNA adducts, define their relationship to disease, and establish clinical tests. Monitoring exposure to environmental and endogenous toxicants can predict, diagnose, and track disease as well as guide therapeutic treatment. DNA adducts are one of the most promising biomarkers of toxicant exposure owing to their stability, appearance in numerous biological matrices, and characteristic analytical properties. In addition, DNA adducts can induce mutations to drive disease onset and progression and can serve as surrogate markers of chemical exposure. In this perspective, we highlight significant advances made within the past decade regarding DNA adduct quantitation using mass spectrometry. We hope to expose a broader audience to this field and encourage analytical chemistry laboratories to explore how specific adducts may be related to various pathologies. One of the limiting factors in developing clinical tests to measure DNA adducts is cohort size; ideally, the cohort would allow for model development and then testing of the model to the remaining cohort. The goals of this perspective article are to (1) provide a summary of analyte levels measured using state-of-the-art analytical methods, (2) foster collaboration, and (3) highlight areas in need of further investigation.
Collapse
Affiliation(s)
- Carlos Hernandez-Castillo
- Department of Molecular Medicine , Beckman Research Institute at City of Hope Duarte , California 91010 , United States
| | - John Termini
- Department of Molecular Medicine , Beckman Research Institute at City of Hope Duarte , California 91010 , United States
| | - Sarah Shuck
- Department of Molecular Medicine , Beckman Research Institute at City of Hope Duarte , California 91010 , United States
| |
Collapse
|
21
|
Cimbalo A, Alonso-Garrido M, Font G, Manyes L. Toxicity of mycotoxins in vivo on vertebrate organisms: A review. Food Chem Toxicol 2020; 137:111161. [PMID: 32014537 DOI: 10.1016/j.fct.2020.111161] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 01/21/2020] [Accepted: 01/22/2020] [Indexed: 12/31/2022]
Abstract
Mycotoxins are considered to be a major risk factor affecting human and animal health as they are one of the most dangerous contaminants of food and feed. This review aims to compile the research developed up to date on the toxicological effects that mycotoxins can induce on human health, through the examination of a selected number of studies in vivo. AFB1 shows to be currently the most studied mycotoxin in vivo, followed by DON, ZEA and OTA. Scarce data was found for FBs, PAT, CIT, AOH and Fusarium emerging mycotoxins. The majority of them concerned the investigation of immunotoxicity, whereas the rest consisted in the study of genotoxicity, oxidative stress, hepatotoxicity, cytotoxicity, teratogenicity and neurotoxicity. In order to assess the risk, a wide range of different techniques have been employed across the reviewed studies: qPCR, ELISA, IHC, WB, LC-MS/MS, microscopy, enzymatic assays, microarray and RNA-Seq. In the last decade, the attention has been drawn to immunologic and transcriptomic aspects of mycotoxins' action, confirming their toxicity at molecular level. Even though, more in vivo studies are needed to further investigate their mechanism of action on human health.
Collapse
Affiliation(s)
- A Cimbalo
- Laboratory of Food Chemistry and Toxicology, Faculty of Pharmacy, University of Valencia, Avinguda Vicent Andrés Estellés S/n, 46100, Burjassot, Spain.
| | - M Alonso-Garrido
- Laboratory of Food Chemistry and Toxicology, Faculty of Pharmacy, University of Valencia, Avinguda Vicent Andrés Estellés S/n, 46100, Burjassot, Spain
| | - G Font
- Laboratory of Food Chemistry and Toxicology, Faculty of Pharmacy, University of Valencia, Avinguda Vicent Andrés Estellés S/n, 46100, Burjassot, Spain
| | - L Manyes
- Laboratory of Food Chemistry and Toxicology, Faculty of Pharmacy, University of Valencia, Avinguda Vicent Andrés Estellés S/n, 46100, Burjassot, Spain
| |
Collapse
|
22
|
Benkerroum N. Chronic and Acute Toxicities of Aflatoxins: Mechanisms of Action. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:E423. [PMID: 31936320 PMCID: PMC7013914 DOI: 10.3390/ijerph17020423] [Citation(s) in RCA: 173] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 12/23/2019] [Accepted: 12/29/2019] [Indexed: 01/01/2023]
Abstract
There are presently more than 18 known aflatoxins most of which have been insufficiently studied for their incidence, health-risk, and mechanisms of toxicity to allow effective intervention and control means that would significantly and sustainably reduce their incidence and adverse effects on health and economy. Among these, aflatoxin B1 (AFB1) has been by far the most studied; yet, many aspects of the range and mechanisms of the diseases it causes remain to be elucidated. Its mutagenicity, tumorigenicity, and carcinogenicity-which are the best known-still suffer from limitations regarding the relative contribution of the oxidative stress and the reactive epoxide derivative (Aflatoxin-exo 8,9-epoxide) in the induction of the diseases, as well as its metabolic and synthesis pathways. Additionally, despite the well-established additive effects for carcinogenicity between AFB1 and other risk factors, e.g., hepatitis viruses B and C, and the hepatotoxic algal microcystins, the mechanisms of this synergy remain unclear. This study reviews the most recent advances in the field of the mechanisms of toxicity of aflatoxins and the adverse health effects that they cause in humans and animals.
Collapse
Affiliation(s)
- Noreddine Benkerroum
- Department of Food Science and Agricultural Chemistry MacDonald Campus, McGill University, 21111 Lakeshore, Ste Anne de Bellevue, QC H9X 3V9, Canada
| |
Collapse
|
23
|
Wang C, Qian J, An K, Lu X, Huang X. A semiconductor quantum dot-based ratiometric electrochemical aptasensor for the selective and reliable determination of aflatoxin B1. Analyst 2019; 144:4772-4780. [PMID: 31268094 DOI: 10.1039/c9an00825j] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In recent years, a ratiometric electrochemical method has been investigated due to its ability to effectively reduce the background electrical signals via the introduction of an internal calibration mechanism, which has great practical significance in the detection of mycotoxins in foods. Herein, we report a ratiometric electrochemical aptasensor based on two semiconductor quantum dots (i.e. CdTe and PbS QDs) for the detection of aflatoxin B1 (AFB1). The aptasensor was fabricated by immobilizing PbS QD-coated silica hybrid spheres (SiO2@PbS) onto CdTe QD-modified Fe3O4@SiO2 (Fe3O4@SiO2/CdTe) surface through biorecognition between the aptamer and complementary DNAs, where PbS QDs acted as external signal labels and CdTe QDs acted as internal reference labels. In the presence of AFB1, the aptamer connected to SiO2@PbS preferred to form an aptamer/AFB1 complex, which brought about the separation of SiO2@PbS linked with the CdTe QDs; with the addition of more AFB1 to the solution, the amount of SiO2@PbS present on the Fe3O4@SiO2/CdTe surface reduced. After several steps of endonuclease cleavage, magnetic separation, and dissolution with acid, the square wave voltammetry signals of Pb2+ and Cd2+ maintained an inverse relationship with the target content based on the SWV stripping measurements; the proposed method had the wide linear range of 5 pg mL-1-50 ng mL-1 and the determination limit of 4.5 pg mL-1 (S/N = 3) and was applied for the detection of AFB1 in peanuts. The proposed aptasensor has an important practical significance for the development of food safety.
Collapse
Affiliation(s)
- Chengquan Wang
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, PR China.
| | | | | | | | | |
Collapse
|
24
|
Recognition of DNA adducts by edited and unedited forms of DNA glycosylase NEIL1. DNA Repair (Amst) 2019; 85:102741. [PMID: 31733589 DOI: 10.1016/j.dnarep.2019.102741] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 10/21/2019] [Accepted: 10/24/2019] [Indexed: 12/18/2022]
Abstract
Pre-mRNA encoding human NEIL1 undergoes editing by adenosine deaminase ADAR1 that converts a single adenosine to inosine, and this conversion results in an amino acid change of lysine 242 to arginine. Previous investigations of the catalytic efficiencies of the two forms of the enzyme revealed differential release of thymine glycol (ThyGly) from synthetic oligodeoxynucleotides, with the unedited form, NEIL1 K242 being ≈30-fold more efficient than the edited NEIL1 K242R. In contrast, when these enzymes were reacted with oligodeoxynucleotides containing guanidinohydantoin or spiroiminohydantoin, the edited K242R form was ≈3-fold more efficient than the unedited NEIL1. However, no prior studies have investigated the efficiencies of these two forms of NEIL1 on either high-molecular weight DNA containing multiple oxidatively-induced base damages, or oligodeoxynucleotides containing a bulky alkylated formamidopyrimidine. To understand the extent of changes in substrate recognition, γ-irradiated calf thymus DNA was treated with either edited or unedited NEIL1 and the released DNA base lesions analyzed by gas chromatography-tandem mass spectrometry. Of all the measured DNA lesions, imidazole ring-opened 4,6-diamino-5-formamidopyrimidine (FapyAde) and 2,6-diamino-4-hydroxy-5-formamidopyrimidine (FapyGua) were preferentially released by both NEIL1 enzymes with K242R being ≈1.3 and 1.2-fold more efficient than K242 on excision of FapyAde and FapyGua, respectively. Consistent with the prior literature, large differences (≈7.5 to 12-fold) were measured in the excision of ThyGly from genomic DNA by the unedited versus edited NEIL1. In contrast, the edited NEIL1 was more efficient (≈3 to 5-fold) on release of 5-hydroxycytosine. Excision kinetics on DNA containing a site-specific aflatoxin B1-FapyGua adduct revealed an ≈1.4-fold higher rate by the unedited NEIL1. Molecular modeling provides insight into these differential substrate specificities. The results of this study and in particular, the comparison of substrate specificities of unedited and edited NEIL1 using biologically and clinically important base lesions, are critical for defining its role in preservation of genomic integrity.
Collapse
|
25
|
Tang Y, Zhang JL. Recent developments in DNA adduct analysis using liquid chromatography coupled with mass spectrometry. J Sep Sci 2019; 43:31-55. [PMID: 31573133 DOI: 10.1002/jssc.201900737] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 09/04/2019] [Accepted: 09/27/2019] [Indexed: 12/15/2022]
Abstract
The formation of DNA adducts by genotoxic agents is an early event in cancer development, and it may lead to gene mutations, thereby initiating tumor development. The measurement of DNA adducts can provide critical information about the genotoxic potential of a chemical and its mechanism of carcinogenesis. In recent decades, liquid chromatography coupled with mass spectrometry has become the most important technique for analyzing DNA adducts. The improvements in resolution achievable with new chromatographic separation techniques coupled with the high specificity and sensitivity and wide dynamic range of new mass spectrometry systems have been used for both qualitative and quantitative analyses of DNA adducts. This review discusses the challenges in qualitative and quantitative analyses of DNA adducts by liquid chromatography coupled with mass spectrometry and highlights recent developments towards overcoming the limitations of liquid chromatography coupled with mass spectrometry methods. The key steps and new solutions, such as sample preparation, mass spectrometry fragmentation, and method validation, are summarized. In addition, the fundamental principles and latest advances in DNA adductomic approaches are reviewed.
Collapse
Affiliation(s)
- Yu Tang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, P. R. China
| | - Jin-Lan Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, P. R. China
| |
Collapse
|
26
|
Minko IG, Vartanian VL, Tozaki NN, Linde OK, Jaruga P, Coskun SH, Coskun E, Qu C, He H, Xu C, Chen T, Song Q, Jiao Y, Stone MP, Egli M, Dizdaroglu M, McCullough AK, Lloyd RS. Characterization of rare NEIL1 variants found in East Asian populations. DNA Repair (Amst) 2019; 79:32-39. [PMID: 31100703 DOI: 10.1016/j.dnarep.2019.05.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 04/30/2019] [Accepted: 05/01/2019] [Indexed: 10/26/2022]
Abstract
The combination of chronic dietary exposure to the fungal toxin, aflatoxin B1 (AFB1), and hepatitis B viral (HBV) infection is associated with an increased risk for early onset hepatocellular carcinomas (HCCs). An in-depth knowledge of the mechanisms driving carcinogenesis is critical for the identification of genetic risk factors affecting the susceptibility of individuals who are HBV infected and AFB1 exposed. AFB1-induced mutagenesis is characterized by G to T transversions. Hence, the DNA repair pathways that function on AFB1-induced DNA adducts or base damage from HBV-induced inflammation are anticipated to have a strong role in limiting carcinogenesis. These pathways define the mutagenic burden in the target tissues and ultimately limit cellular progression to cancer. Murine data have demonstrated that NEIL1 in the DNA base excision repair pathway was significantly more important than nucleotide excision repair relative to elevated risk for induction of HCCs. These data suggest that deficiencies in NEIL1 could contribute to the initiation of HCCs in humans. To investigate this hypothesis, publicly-available data on variant alleles of NEIL1 were analyzed and compared with genome sequencing data from HCC tissues derived from individuals residing in Qidong County (China). Three variant alleles were identified and the corresponding A51V, P68H, and G245R enzymes were characterized for glycosylase activity on genomic DNA containing a spectrum of oxidatively-induced base damage and an oligodeoxynucleotide containing a site-specific AFB1-formamidopyrimidine guanine adduct. Although the efficiency of the P68H variant was modestly decreased, the A51V and G245R variants showed nearly wild-type activities. Consistent with biochemical findings, molecular modeling of these variants demonstrated only slight local structural alterations. However, A51V was highly temperature sensitive suggesting that its biological activity would be greatly reduced. Overall, these studies have direct human health relevance pertaining to genetic risk factors and biochemical pathways previously not recognized as germane to induction of HCCs.
Collapse
Affiliation(s)
- Irina G Minko
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, 97239, United States
| | - Vladimir L Vartanian
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, 97239, United States
| | - Naoto N Tozaki
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, 97239, United States
| | - Oskar K Linde
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, 97239, United States
| | - Pawel Jaruga
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, United States
| | - Sanem Hosbas Coskun
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, United States
| | - Erdem Coskun
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, United States
| | - Chunfeng Qu
- State Key Lab of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 100021, Beijing, China
| | - Huan He
- State Key Lab of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 100021, Beijing, China
| | - Chungui Xu
- State Key Lab of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 100021, Beijing, China
| | - Taoyang Chen
- Qidong Liver Cancer Institute & Qidong People's Hospital, Qidong, 226200, Jiangsu Province, China
| | - Qianqian Song
- State Key Lab of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 100021, Beijing, China
| | - Yuchen Jiao
- State Key Lab of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 100021, Beijing, China
| | - Michael P Stone
- Department of Chemistry, Vanderbilt University, Nashville, TN, 37235, United States
| | - Martin Egli
- Department of Biochemistry, Vanderbilt University, Nashville, TN, 37232, United States
| | - Miral Dizdaroglu
- Biomolecular Measurement Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, United States
| | - Amanda K McCullough
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, 97239, United States; Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR, 97239, United States
| | - R Stephen Lloyd
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, 97239, United States; Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR, 97239, United States; Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR, 97239, United States.
| |
Collapse
|
27
|
McCullough AK, Lloyd RS. Mechanisms underlying aflatoxin-associated mutagenesis - Implications in carcinogenesis. DNA Repair (Amst) 2019; 77:76-86. [PMID: 30897375 PMCID: PMC6959417 DOI: 10.1016/j.dnarep.2019.03.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 03/01/2019] [Accepted: 03/05/2019] [Indexed: 01/07/2023]
Abstract
Chronic dietary exposure to aflatoxin B1 (AFB1), concomitant with hepatitis B infection is associated with a significant increased risk for hepatocellular carcinomas (HCCs) in people living in Southeast Asia and sub-Saharan Africa. Human exposures to AFB1 occur through the consumption of foods that are contaminated with pervasive molds, including Aspergillus flavus. Even though dietary exposures to aflatoxins constitute the second largest global environmental risk factor for cancer development, there are still significant questions concerning the molecular mechanisms driving carcinogenesis and what factors may modulate an individual's risk for HCC. The objective of this review is to summarize key discoveries that established the association of chronic inflammation (most commonly associated with hepatitis B viral (HBV) infection) and environmental exposures to aflatoxin with increased HCC risk. Special emphasis will be given to recent investigations that have: 1) refined the aflatoxin-associated mutagenic signature, 2) expanded the DNA repair mechanisms that limit mutagenesis via adduct removal prior to replication-induced mutagenesis, 3) implicated a specific DNA polymerase in the error-prone bypass and resulting mutagenesis, and 4) identified human polymorphic variants that may modulate individual susceptibility to aflatoxin-induced cancers. Collectively, these investigations revealed that specific sequence contexts are differentially resistant against, or prone to, aflatoxin-induced mutagenesis and that these associations are remarkably similar between in vitro and in vivo analyses. These recent investigations also established DNA polymerase ζ as the major polymerase that confers the G to T transversion signature. Additionally, although the nucleotide excision repair (NER) pathway has been previously shown to repair aflatoxin-induced DNA adducts, recent murine data demonstrated that NEIL1-initiated base excision repair was significantly more important than NER relative to the removal of the highly mutagenic AFB1-Fapy-dG adducts. These data suggest that inactivating polymorphic variants of NEIL1 could be a potential driver of HCCs in aflatoxin-exposed populations.
Collapse
Affiliation(s)
- Amanda K McCullough
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, United States; Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR 97239, United States
| | - R Stephen Lloyd
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, United States; Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR 97239, United States; Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR 97239, United States.
| |
Collapse
|