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Mao X, Liu S, Ge L, Du H, Yue D, Hou L, Huang K, Chen X. mTOR-Mediated Autophagy Regulates Fumonisin B 1-Induced Intestinal Inflammation via Pyroptosis In Vivo and In Vitro. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:9187-9200. [PMID: 35830273 DOI: 10.1021/acs.jafc.2c03025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Fumonisin B1 (FB1) is a fungal metabolite, which has an incremental detection rate in grains and feed worldwide. The nucleotide-binding oligomerization domain-like pyrin domain containing protein 3 (NLRP3) inflammasome is a critical element in pyroptosis activation, which participates in regulating enteritis. Meanwhile, autophagy is also engaged in intestinal inflammation. However, the function of pyroptosis and autophagy in FB1-mediated enterotoxicity remains unclear. In this study, we explored the effects of FB1 on enteritis and the underlying mechanism in vivo and in vitro. Our data showed that FB1 exposure damaged the intestinal epithelium and promoted the secretion of inflammatory cytokines. Meanwhile, FB1 exposure significantly upregulated the expression of pyroptosis-related genes. Then, MCC950, an inhibitor of NLRP3, significantly blocked FB1-induced pyroptosis in IPEC-J2 cells. In addition, FB1 treatment elevated the levels of autophagy. Moreover, the phosphorylation of the mammalian target of rapamycin (mTOR), an upstream protein of the autophagy pathway, was inhibited by FB1 exposure. Notably, rapamycin, an inhibitor of mTOR, instead of MHY1485, an agonist of mTOR, could ameliorate FB1-induced intestinal inflammatory injury and inhibit the upregulation of pyroptosis-related genes. In summary, we demonstrated that autophagy exhibited a protective effect against NLRP3 inflammasome-dependent pyroptosis on FB1-induced enteritis. Our data clarify a favorable protective role for the activation of autophagy in FB1 poisoning.
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Affiliation(s)
- Xinru Mao
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
- Institute of Animal Nutritional Health, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
| | - Shuiping Liu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
- Institute of Animal Nutritional Health, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
| | - Lei Ge
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
- Institute of Animal Nutritional Health, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
| | - Heng Du
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
- Institute of Animal Nutritional Health, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
| | - Dongmei Yue
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
- Institute of Animal Nutritional Health, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
| | - Lili Hou
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
- Institute of Animal Nutritional Health, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
| | - Kehe Huang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
- Institute of Animal Nutritional Health, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
| | - Xingxiang Chen
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
- Institute of Animal Nutritional Health, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China
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2
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Thomas JP, Modos D, Rushbrook SM, Powell N, Korcsmaros T. The Emerging Role of Bile Acids in the Pathogenesis of Inflammatory Bowel Disease. Front Immunol 2022; 13:829525. [PMID: 35185922 PMCID: PMC8850271 DOI: 10.3389/fimmu.2022.829525] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 01/14/2022] [Indexed: 12/12/2022] Open
Abstract
Inflammatory bowel disease (IBD) is a chronic immune-mediated inflammatory disorder of the gastrointestinal tract that arises due to complex interactions between host genetic risk factors, environmental factors, and a dysbiotic gut microbiota. Although metagenomic approaches have attempted to characterise the dysbiosis occurring in IBD, the precise mechanistic pathways interlinking the gut microbiota and the intestinal mucosa are still yet to be unravelled. To deconvolute these complex interactions, a more reductionist approach involving microbial metabolites has been suggested. Bile acids have emerged as a key class of microbiota-associated metabolites that are perturbed in IBD patients. In recent years, metabolomics studies have revealed a consistent defect in bile acid metabolism with an increase in primary bile acids and a reduction in secondary bile acids in IBD patients. This review explores the evolving evidence that specific bile acid metabolites interact with intestinal epithelial and immune cells to contribute to the inflammatory milieu seen in IBD. Furthermore, we summarise evidence linking bile acids with intracellular pathways that are known to be relevant in IBD including autophagy, apoptosis, and the inflammasome pathway. Finally, we discuss how novel experimental and bioinformatics approaches could further advance our understanding of the role of bile acids and inform novel therapeutic strategies in IBD.
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Affiliation(s)
- John P Thomas
- Gut Microbes and Health Programme, Quadram Bioscience, Norwich, United Kingdom.,Organisms and Ecosystem, Earlham Institute, Norwich, United Kingdom.,Department of Gastroenterology, Norfolk and Norwich University Hospital, Norwich, United Kingdom
| | - Dezso Modos
- Gut Microbes and Health Programme, Quadram Bioscience, Norwich, United Kingdom.,Organisms and Ecosystem, Earlham Institute, Norwich, United Kingdom
| | - Simon M Rushbrook
- Gut Microbes and Health Programme, Quadram Bioscience, Norwich, United Kingdom.,Department of Gastroenterology, Norfolk and Norwich University Hospital, Norwich, United Kingdom.,Department of Hepatology, University of East Anglia Medical School, Norwich, United Kingdom
| | - Nick Powell
- Division of Digestive Diseases, Imperial College London, London, United Kingdom
| | - Tamas Korcsmaros
- Gut Microbes and Health Programme, Quadram Bioscience, Norwich, United Kingdom.,Organisms and Ecosystem, Earlham Institute, Norwich, United Kingdom.,Division of Digestive Diseases, Imperial College London, London, United Kingdom
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3
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Approaching precision medicine by tailoring the microbiota. Mamm Genome 2021; 32:206-222. [PMID: 33646347 DOI: 10.1007/s00335-021-09859-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 02/10/2021] [Indexed: 10/22/2022]
Abstract
Accumulating evidence has revealed the link between the microbiota and various human diseases. Advances in high-throughput sequencing technologies have identified some consistent disease-associated microbial features, leading to the emerging concept of microbiome-based therapeutics. However, it is also becoming clear that there are considerable variations in the microbiota among patients with the same disease. Variations in the microbial composition and function contribute to substantial differences in metabolic status of the host via production of a myriad of biochemically and functionally different microbial metabolites. Indeed, compelling evidence indicates that individuality of the microbiome may result in individualized responses to microbiome-based therapeutics and other interventions. Mechanistic understanding of the role of the microbiota in diseases and drug metabolism would help us to identify causal relationships and thus guide the development of microbiome-based precision or personalized medicine. In this review, we provide an overview of current efforts to use microbiome-based interventions for the treatment of diseases such as cancer, neurological disorders, and diabetes to approach precision medicine.
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4
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Hu YJ, Zhong JT, Gong L, Zhang SC, Zhou SH. Autophagy-Related Beclin 1 and Head and Neck Cancers. Onco Targets Ther 2020; 13:6213-6227. [PMID: 32669852 PMCID: PMC7335767 DOI: 10.2147/ott.s256072] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 06/10/2020] [Indexed: 12/11/2022] Open
Abstract
Beclin 1, a positive regulator of autophagy, behaves as a double-edged sword in tumorigenesis. Beclin 1 contributes to tumor suppression by removing defective or damaged organelles and other cellular components; however, its activity can also stimulate cancer initiation and progression. In head and neck cancer, Beclin 1 overexpression promotes autophagy, which limits DNA damage and chromosomal instability and increases necrosis and inflammation by impacting apoptotic and autophagic pathways. This paper reviews the relationship between Beclin 1, carcinogenesis and head and neck cancer prognosis.
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Affiliation(s)
- Yang-Jie Hu
- Department of Otolaryngology, The Affiliated Cixi Hospital of Wenzhou Medical University, Cixi 315300, Zhejiang, People's Republic of China.,Department of Otolaryngology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, People's Republic of China
| | - Jiang-Tao Zhong
- Department of Otolaryngology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, People's Republic of China
| | - Liang Gong
- Department of Otolaryngology, The Affiliated Cixi Hospital of Wenzhou Medical University, Cixi 315300, Zhejiang, People's Republic of China
| | - Si-Cong Zhang
- Department of Otolaryngology, The Affiliated Cixi Hospital of Wenzhou Medical University, Cixi 315300, Zhejiang, People's Republic of China
| | - Shui-Hong Zhou
- Department of Otolaryngology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, People's Republic of China
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5
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Tsai MS, Lee HM, Huang SC, Sun CK, Chiu TC, Chen PH, Lin YC, Hung TM, Lee PH, Kao YH. Nerve growth factor induced farnesoid X receptor upregulation modulates autophagy flux and protects hepatocytes in cholestatic livers. Arch Biochem Biophys 2020; 682:108281. [PMID: 32001246 DOI: 10.1016/j.abb.2020.108281] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 01/20/2020] [Accepted: 01/24/2020] [Indexed: 02/08/2023]
Abstract
Upregulation of nerve growth factor (NGF) in parenchymal hepatocytes has been shown to exert hepatoprotective function during cholestatic liver injury. However, the modulatory role of NGF in regulation of liver autophagy remains unclear. This study aimed to scrutinize the regulatory role of NGF in hepatic expression of farnesoid X receptor (FXR), a bile acid (BA)-activated nuclear receptor, and to determine its cytoprotective effect on BA-induced autophagy and cytotoxicity. Livers of human hepatolithiasis and bile duct ligation (BDL)-induced mouse cholestasis were used for histopathological and molecular detection. The regulatory roles of NGF in autophagy flux and FXR expression, as well as its hepatoprotection against BA cytotoxicity were examined in cultured hepatocytes. FXR downregulation in human hepatolithiasis livers showed positive correlation with hepatic NGF levels. NGF administration upregulated hepatic FXR levels, while neutralization of NGF decreased FXR expression in BDL-induced cholestatic mouse livers. In vitro studies demonstrated that NGF upregulated FXR expression, increased cellular LC3 levels, and exerted hepatoprotective effect in cultured primary rat hepatocytes. Conversely, autophagy inhibition abrogated NGF-driven cytoprotection under BA exposure, suggesting involvement of NGF-modulated auophagy flux. Although FXR agonistic GW4064 stimulation did not affect auophagic LC3 levels, FXR activity inhibition significantly potentiated BA-induced cytotoxicity and increased cellular p62/SQSTM1 and Rab7 protein in SK-Hep1 hepatocytes. Moreover, FXR gene silencing abolished the protective effect of NGF under BA exposure. These findings support that NGF modulates autophagy flux via FXR upregulation and protects hepatocytes against BA-induced cytotoxicity. NGF/FXR axis is a novel therapeutic target for treatment of cholestatic liver diseases.
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Affiliation(s)
- Ming-Shian Tsai
- Department of Surgery, E-Da Hospital, Kaohsiung, Taiwan; Body Health and Beauty Center, Jiann-Ren Hospital, Kaohsiung, Taiwan
| | - Hui-Ming Lee
- Department of Surgery, E-Da Hospital, Kaohsiung, Taiwan
| | - Shih-Che Huang
- Department of Medical Research, E-Da Hospital, Kaohsiung, Taiwan
| | - Cheuk-Kwan Sun
- Department of Medical Research, E-Da Hospital, Kaohsiung, Taiwan; Department of Emergency Medicine, E-Da Hospital, Kaohsiung, Taiwan; School of Medicine, College of Medicine, I-Shou University, Kaohsiung, Taiwan
| | | | - Po-Han Chen
- Department of Medical Research, E-Da Hospital, Kaohsiung, Taiwan
| | - Yu-Chun Lin
- Department of Surgery, E-Da Hospital, Kaohsiung, Taiwan
| | - Tzu-Min Hung
- Department of Medical Research, E-Da Hospital, Kaohsiung, Taiwan; Committee for Integration and Promotion of Advanced Medicine and Biotechnology, E-Da Healthcare Group, Kaohsiung, Taiwan
| | - Po-Huang Lee
- Department of Surgery, E-Da Hospital, Kaohsiung, Taiwan; Committee for Integration and Promotion of Advanced Medicine and Biotechnology, E-Da Healthcare Group, Kaohsiung, Taiwan.
| | - Ying-Hsien Kao
- Department of Medical Research, E-Da Hospital, Kaohsiung, Taiwan.
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6
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Tang W, Putluri V, Ambati CR, Dorsey TH, Putluri N, Ambs S. Liver- and Microbiome-derived Bile Acids Accumulate in Human Breast Tumors and Inhibit Growth and Improve Patient Survival. Clin Cancer Res 2019; 25:5972-5983. [PMID: 31296531 DOI: 10.1158/1078-0432.ccr-19-0094] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 05/24/2019] [Accepted: 07/08/2019] [Indexed: 01/08/2023]
Abstract
PURPOSE Metabolomics is a discovery tool for novel associations of metabolites with disease. Here, we interrogated the metabolome of human breast tumors to describe metabolites whose accumulation affects tumor biology. EXPERIMENTAL DESIGN We applied large-scale metabolomics followed by absolute quantification and machine learning-based feature selection using LASSO to identify metabolites that show a robust association with tumor biology and disease outcome. Key observations were validated with the analysis of an independent dataset and cell culture experiments. RESULTS LASSO-based feature selection revealed an association of tumor glycochenodeoxycholate levels with improved breast cancer survival, which was confirmed using a Cox proportional hazards model. Absolute quantification of four bile acids, including glycochenodeoxycholate and microbiome-derived deoxycholate, corroborated the accumulation of bile acids in breast tumors. Levels of glycochenodeoxycholate and other bile acids showed an inverse association with the proliferation score in tumors and the expression of cell-cycle and G2-M checkpoint genes, which was corroborated with cell culture experiments. Moreover, tumor levels of these bile acids markedly correlated with metabolites in the steroid metabolism pathway and increased expression of key genes in this pathway, suggesting that bile acids may interfere with hormonal pathways in the breast. Finally, a proteome analysis identified the complement and coagulation cascade as being upregulated in glycochenodeoxycholate-high tumors. CONCLUSIONS We describe the unexpected accumulation of liver- and microbiome-derived bile acids in breast tumors. Tumors with increased bile acids show decreased proliferation, thus fall into a good prognosis category, and exhibit significant changes in steroid metabolism.
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Affiliation(s)
- Wei Tang
- Laboratory of Human Carcinogenesis, Center for Cancer Research (CCR), NCI, NIH, Bethesda, Maryland
| | - Vasanta Putluri
- Department of Molecular and Cellular Biology, Verna and Marrs McLean Department of Biochemistry and Alkek Center for Molecular Discovery, Baylor College of Medicine, Houston, Texas
| | - Chandrashekar R Ambati
- Department of Molecular and Cellular Biology, Verna and Marrs McLean Department of Biochemistry and Alkek Center for Molecular Discovery, Baylor College of Medicine, Houston, Texas
| | - Tiffany H Dorsey
- Laboratory of Human Carcinogenesis, Center for Cancer Research (CCR), NCI, NIH, Bethesda, Maryland
| | - Nagireddy Putluri
- Department of Molecular and Cellular Biology, Verna and Marrs McLean Department of Biochemistry and Alkek Center for Molecular Discovery, Baylor College of Medicine, Houston, Texas.
| | - Stefan Ambs
- Laboratory of Human Carcinogenesis, Center for Cancer Research (CCR), NCI, NIH, Bethesda, Maryland.
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7
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Hegyi P, Maléth J, Walters JR, Hofmann AF, Keely SJ. Guts and Gall: Bile Acids in Regulation of Intestinal Epithelial Function in Health and Disease. Physiol Rev 2019; 98:1983-2023. [PMID: 30067158 DOI: 10.1152/physrev.00054.2017] [Citation(s) in RCA: 159] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Epithelial cells line the entire surface of the gastrointestinal tract and its accessory organs where they primarily function in transporting digestive enzymes, nutrients, electrolytes, and fluid to and from the luminal contents. At the same time, epithelial cells are responsible for forming a physical and biochemical barrier that prevents the entry into the body of harmful agents, such as bacteria and their toxins. Dysregulation of epithelial transport and barrier function is associated with the pathogenesis of a number of conditions throughout the intestine, such as inflammatory bowel disease, chronic diarrhea, pancreatitis, reflux esophagitis, and cancer. Driven by discovery of specific receptors on intestinal epithelial cells, new insights into mechanisms that control their synthesis and enterohepatic circulation, and a growing appreciation of their roles as bioactive bacterial metabolites, bile acids are currently receiving a great deal of interest as critical regulators of epithelial function in health and disease. This review aims to summarize recent advances in this field and to highlight how bile acids are now emerging as exciting new targets for disease intervention.
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Affiliation(s)
- Peter Hegyi
- Momentum Translational Gastroenterology Research Group, Hungarian Academy of Sciences-University of Szeged , Szeged , Hungary ; Institute for Translational Medicine, Medical School, University of Pécs , Pécs , Hungary ; Momentum Epithelial Cell Signalling and Secretion Research Group and First Department of Medicine, University of Szeged , Szeged , Hungary ; Division of Digestive Diseases, Department of Gastroenterology, Hammersmith Hospital, Imperial College London , London , United Kingdom ; Division of Gastroenterology, Department of Medicine, University of California, San Diego, La Jolla, California ; and Department of Molecular Medicine, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital , Dublin , Ireland
| | - Joszef Maléth
- Momentum Translational Gastroenterology Research Group, Hungarian Academy of Sciences-University of Szeged , Szeged , Hungary ; Institute for Translational Medicine, Medical School, University of Pécs , Pécs , Hungary ; Momentum Epithelial Cell Signalling and Secretion Research Group and First Department of Medicine, University of Szeged , Szeged , Hungary ; Division of Digestive Diseases, Department of Gastroenterology, Hammersmith Hospital, Imperial College London , London , United Kingdom ; Division of Gastroenterology, Department of Medicine, University of California, San Diego, La Jolla, California ; and Department of Molecular Medicine, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital , Dublin , Ireland
| | - Julian R Walters
- Momentum Translational Gastroenterology Research Group, Hungarian Academy of Sciences-University of Szeged , Szeged , Hungary ; Institute for Translational Medicine, Medical School, University of Pécs , Pécs , Hungary ; Momentum Epithelial Cell Signalling and Secretion Research Group and First Department of Medicine, University of Szeged , Szeged , Hungary ; Division of Digestive Diseases, Department of Gastroenterology, Hammersmith Hospital, Imperial College London , London , United Kingdom ; Division of Gastroenterology, Department of Medicine, University of California, San Diego, La Jolla, California ; and Department of Molecular Medicine, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital , Dublin , Ireland
| | - Alan F Hofmann
- Momentum Translational Gastroenterology Research Group, Hungarian Academy of Sciences-University of Szeged , Szeged , Hungary ; Institute for Translational Medicine, Medical School, University of Pécs , Pécs , Hungary ; Momentum Epithelial Cell Signalling and Secretion Research Group and First Department of Medicine, University of Szeged , Szeged , Hungary ; Division of Digestive Diseases, Department of Gastroenterology, Hammersmith Hospital, Imperial College London , London , United Kingdom ; Division of Gastroenterology, Department of Medicine, University of California, San Diego, La Jolla, California ; and Department of Molecular Medicine, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital , Dublin , Ireland
| | - Stephen J Keely
- Momentum Translational Gastroenterology Research Group, Hungarian Academy of Sciences-University of Szeged , Szeged , Hungary ; Institute for Translational Medicine, Medical School, University of Pécs , Pécs , Hungary ; Momentum Epithelial Cell Signalling and Secretion Research Group and First Department of Medicine, University of Szeged , Szeged , Hungary ; Division of Digestive Diseases, Department of Gastroenterology, Hammersmith Hospital, Imperial College London , London , United Kingdom ; Division of Gastroenterology, Department of Medicine, University of California, San Diego, La Jolla, California ; and Department of Molecular Medicine, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital , Dublin , Ireland
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Dong W, Liu L, Dou Y, Xu M, Liu T, Wang S, Zhang Y, Deng B, Wang B, Cao H. Deoxycholic acid activates epidermal growth factor receptor and promotes intestinal carcinogenesis by ADAM17-dependent ligand release. J Cell Mol Med 2018; 22:4263-4273. [PMID: 29956475 PMCID: PMC6111862 DOI: 10.1111/jcmm.13709] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 05/04/2018] [Indexed: 12/12/2022] Open
Abstract
High fat diet is implicated in the elevated deoxycholic acid (DCA) in the intestine and correlated with increased colon cancer risk. However, the potential mechanisms of intestinal carcinogenesis by DCA remain unclarified. Here, we investigated the carcinogenic effects and mechanisms of DCA using the intestinal tumour cells and Apcmin/+ mice model. We found that DCA could activate epidermal growth factor receptor (EGFR) and promote the release of EGFR ligand amphiregulin (AREG), but not HB‐EGF or TGF‐α in intestinal tumour cells. Moreover, ADAM‐17 was required in DCA‐induced promotion of shedding of AREG and activation of EGFR/Akt signalling pathway. DCA significantly increased the multiplicity of intestinal tumours and accelerated adenoma‐carcinoma sequence in Apcmin/+ mice. ADAM‐17/EGFR signalling axis was also activated in intestinal tumours of DCA‐treated Apcmin/+ mice, whereas no significant change occurred in tumour adjacent tissues after DCA exposure. Conclusively, DCA activated EGFR and promoted intestinal carcinogenesis by ADAM17‐dependent ligand release.
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Affiliation(s)
- Wenxiao Dong
- Department of Gastroenterology and Hepatology, General Hospital, Tianjin Medical University, Tianjin, China
| | - Li Liu
- Department of Gastroenterology and Hepatology, General Hospital, Tianjin Medical University, Tianjin, China
| | - Yan Dou
- Department of Gastroenterology and Hepatology, General Hospital, Tianjin Medical University, Tianjin, China
| | - Mengque Xu
- Department of Gastroenterology and Hepatology, General Hospital, Tianjin Medical University, Tianjin, China
| | - Tianyu Liu
- Department of Gastroenterology and Hepatology, General Hospital, Tianjin Medical University, Tianjin, China
| | - Sinan Wang
- Department of Gastroenterology and Hepatology, General Hospital, Tianjin Medical University, Tianjin, China
| | - Yujie Zhang
- Department of Pathology, General Hospital, Tianjin Medical University, Tianjin, China
| | - Baoru Deng
- Department of Gastroenterology and Hepatology, General Hospital, Tianjin Medical University, Tianjin, China
| | - Bangmao Wang
- Department of Gastroenterology and Hepatology, General Hospital, Tianjin Medical University, Tianjin, China
| | - Hailong Cao
- Department of Gastroenterology and Hepatology, General Hospital, Tianjin Medical University, Tianjin, China
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Manley S, Ding W. Role of farnesoid X receptor and bile acids in alcoholic liver disease. Acta Pharm Sin B 2015; 5:158-67. [PMID: 26579442 PMCID: PMC4629219 DOI: 10.1016/j.apsb.2014.12.011] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 12/20/2014] [Accepted: 12/29/2014] [Indexed: 02/07/2023] Open
Abstract
Alcoholic liver disease (ALD) is one of the major causes of liver morbidity and mortality worldwide. Chronic alcohol consumption leads to development of liver pathogenesis encompassing steatosis, inflammation, fibrosis, cirrhosis, and in extreme cases, hepatocellular carcinoma. Moreover, ALD may also associate with cholestasis. Emerging evidence now suggests that farnesoid X receptor (FXR) and bile acids also play important roles in ALD. In this review, we discuss the effects of alcohol consumption on FXR, bile acids and gut microbiome as well as their impacts on ALD. Moreover, we summarize the findings on FXR, FoxO3a (forkhead box-containing protein class O3a) and PPARα (peroxisome proliferator-activated receptor alpha) in regulation of autophagy-related gene transcription program and liver injury in response to alcohol exposure.
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Key Words
- 6ECDCA, 6α-ethyl-chenodeoxycholic acid
- ADH, alcohol dehydrogenase
- AF, activation function
- AKT, protein kinase B
- ALD, alcoholic liver disease
- ALT, alanine aminotransferase
- ASBT, apical sodium dependent bile acid transporter
- Alcoholic liver disease
- Atg, autophagy-related
- Autophagy
- BAAT, bile acid CoA:amino acid N-acyltransferase
- BACS, bile acid CoA synthetase
- BSEP, bile salt export pump
- Bile acids
- CA, cholic acid
- CB1R, cannabinoid receptor type 1
- CDCA, chenodeoxycholic acid
- CREB, cAMP response element-binding protein
- CREBH, cAMP response element-binding protein, hepatocyte specific
- CRTC2, CREB regulated transcription coactivator 2
- CYP, cytochrome P450
- DCA, deoxycholic acid
- DR1, direct repeat 1
- FGF15/19, fibroblast growth factor 15/19
- FGFR4, fibroblast growth factor receptor 4
- FXR, farnesoid X receptor
- Farnesoid X receptor
- FoxO3
- FoxO3a, forkhead box-containing protein class O3a
- GGT, gamma-glutamyltranspeptidase
- HCC, hepatocellular carcinoma
- IR-1, inverted repeat-1
- KO, knockout
- LC3, light chain 3
- LRH-1, liver receptor homolog 1
- LXR, liver X receptor
- MRP4, multidrug resistance protein 4
- NAD+, nicotinamide adenine dinucleotide
- NTCP, sodium taurocholate cotransporting polypeptide
- OSTα/β, organic solute transporter α/β
- PE, phosphatidylethanolamine
- PPARα, peroxisome proliferator-activated receptor alpha
- ROS, reactive oxygen species
- RXRα, retinoid X receptor-alpha
- SHP, small heterodimer partner
- SQSTM, sequestome-1
- SREBP1, sterol regulatory element-binding protein 1
- Sirt1, sirtuin 1
- TCA, taurocholic acid
- TFEB, transcription factor EB
- TLR4, toll-like receptor 4
- TUDCA, tauro-ursodeoxycholic acid
- UDCA, ursodeoxycholic acid
- WAY, WAY-362450
- WT, wild type
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Affiliation(s)
| | - Wenxing Ding
- Corresponding author. Tel.: +1 913 5889813; fax: +1 913 5887501.
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10
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Lin R, Jiang Y, Zhao XY, Guan Y, Qian W, Fu XC, Ren HY, Hou XH. Four types of Bifidobacteria trigger autophagy response in intestinal epithelial cells. J Dig Dis 2014; 15:597-605. [PMID: 25123057 DOI: 10.1111/1751-2980.12179] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES To investigate the influence of gut microbiota on autophagy activation in intestinal epithelial cells (IEC) and to evaluate the IEC autophagy response to different types of Bifidobacteria. METHODS IEC-18 cells were treated with lipopolysaccharide (LPS) derived from enteropathogenic Escherichia coli (EPEC) O127:B8 and culture medium supernatants of four types of Bifidobacteria. Transepithelial electrical resistance (TEER) was measured using an epithelial voltohmmeter. Autophagy was determined by transmission electron microscopy (TEM), the ratio of LC3-II to LC3-I and the persistence of both green fluorescent protein (GFP) and mCherry signals using a tandem mCherry-GFP-LC3 construct. The expression of Atg12-Atg5-Atg16 complex was measured by quantitative real-time polymerase chain reaction. RESULTS EPEC-LPS significantly diminished the TEER of IEC compared with untreated controls by 45-55%. This reduction was not observed after treated with Bifidobacteria at all time points. Bifidobacteria could initiate the activation of autophagy in IEC, based on both the ratio of LC3-II to LC3-I and TEM. There was no difference in the influence of the four types of Bifidobacteria on the autophagy response. Compared with Bifidobacteria, IEC reacted to EPEC-LPS much more intensively by autophagy accumulation. More mCherry(+) LC3 autophagic puncta and increased expressions of autophagy genes Atg5, Atg12 and Atg16 could be detected after being treated with Bifidobacteria and EPEC-LPS. CONCLUSIONS Bifidobacteria initiate autophagy activation in IEC. The Atg12-Atg5-Atg16 multimeric complex might participate in the activation of Bifidobacteria-induced cell autophagy.
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Affiliation(s)
- Rong Lin
- Division of Gastroenterology, Union Hospital, Wuhan, Hubei Province, China
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The secondary bile acid, deoxycholate accelerates intestinal adenoma–adenocarcinoma sequence in Apc min/+ mice through enhancing Wnt signaling. Fam Cancer 2014; 13:563-71. [DOI: 10.1007/s10689-014-9742-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Prasad AR, Prasad S, Nguyen H, Facista A, Lewis C, Zaitlin B, Bernstein H, Bernstein C. Novel diet-related mouse model of colon cancer parallels human colon cancer. World J Gastrointest Oncol 2014; 6:225-243. [PMID: 25024814 PMCID: PMC4092339 DOI: 10.4251/wjgo.v6.i7.225] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Revised: 04/04/2014] [Accepted: 06/18/2014] [Indexed: 02/05/2023] Open
Abstract
AIM: To investigate the close parallels between our novel diet-related mouse model of colon cancer and human colon cancer.
METHODS: Twenty-two wild-type female mice (ages 6-8 wk) were fed the standard control diet (AIN-93G) and an additional 22 female mice (ages 6-8 wk) were fed the control diet supplemented with 0.2% deoxycholic acid [diet + deoxycholic acid (DOC)] for 10 mo. Tumors occurred in the colons of mice fed diet + DOC and showed progression to colon cancer [adenocarcinoma (AC)]. This progression is through the stages of tubular adenoma (TA), TA with high grade dysplasia or adenoma with sessile serrated morphology, intramucosal AC, AC stage T1, and AC stage T2. The mouse tumors were compared to human tumors at the same stages by histopathological analysis. Sections of the small and large intestines of mice and humans were evaluated for glandular architecture, cellular and nuclear morphology including cellular orientation, cellular and nuclear atypia, pleomorphism, mitotic activity, frequency of goblet cells, crypt architecture, ulceration, penetration of crypts through the muscularis mucosa and presence of malignant crypts in the muscularis propria. In addition, preserved colonic tissues from genetically similar male mice, obtained from a prior experiment, were analyzed by immunohistochemistry. The male mice had been fed the control diet or diet + DOC. Four molecular markers were evaluated: 8-OH-dG, DNA repair protein ERCC1, autophagy protein beclin-1 and the nuclear location of beta-catenin in the stem cell region of crypts. Also, male mice fed diet + DOC plus 0.007% chlorogenic acid (diet + DOC + CGA) were evaluated for ERCC1, beclin-1 and nuclear location of beta-catenin.
RESULTS: Humans with high levels of diet-related DOC in their colons are at a substantially increased risk of developing colon cancer. The mice fed diet + DOC had levels of DOC in their colons comparable to that of humans on a high fat diet. The 22 mice without added DOC in their diet had no colonic tumors while 20 of the 22 mice (91%) fed diet + DOC developed colonic tumors. Furthermore, the tumors in 10 of these mice (45% of mice) included an adenocarcinoma. All mice were free of cancers of the small intestine. Histopathologically, the colonic tumor types in the mice were virtually identical to those in humans. In humans, characteristic aberrant changes in molecular markers can be detected both in field defects surrounding cancers (from which cancers arise) and within cancers. In the colonic tissues of mice fed diet + DOC similar changes in biomarkers appeared to occur. Thus, 8-OH-dG was increased, DNA repair protein ERCC1 was decreased, autophagy protein beclin-1 was increased and, in the stem cell region at the base of crypts there was substantial nuclear localization of beta-catenin as well as increased cytoplasmic beta-catenin. However, in mice fed diet + DOC + CGA (with reduced frequency of cancer) and evaluated for ERCC1, beclin-1, and beta-catenin in the stem cell region of crypts, mouse tissue showed amelioration of the aberrancies, suggesting that chlorogenic acid is protective at the molecular level against colon cancer. This is the first diet-related model of colon cancer that closely parallels human progression to colon cancer, both at the histomorphological level as well as in its molecular profile.
CONCLUSION: The diet-related mouse model of colon cancer parallels progression to colon cancer in humans, and should be uniquely useful in model studies of prevention and therapeutics.
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Roesly HB, Khan MR, Chen HDR, Hill KA, Narendran N, Watts GS, Chen X, Dvorak K. The decreased expression of Beclin-1 correlates with progression to esophageal adenocarcinoma: the role of deoxycholic acid. Am J Physiol Gastrointest Liver Physiol 2012; 302:G864-72. [PMID: 22301112 PMCID: PMC3355563 DOI: 10.1152/ajpgi.00340.2011] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Beclin-1 has a central role in the regulation of autophagy. Barrett's esophagus (BE) is associated with a significantly increased risk for the development of esophageal adenocarcinoma (EAC). In the current study, we evaluated the role of Beclin-1 and autophagy in the EAC. Biopsies obtained from patients with BE and EAC, tissues from a rat model of BE and EAC, and esophageal cell lines were evaluated for the expression of Beclin-1 by immunohistochemistry, immunoblotting, or RT-PCR. Since reflux of bile acids is important in EAC, we also evaluated the effect of exposure to deoxycholic acid (DCA) on autophagy and Beclin-1 expression. Beclin-1 expression was high in squamous epithelium and nondysplastic BE, whereas its expression was low in dysplastic BE and EAC. The same pattern of expression was observed in rat tissues and in esophageal cell lines. Normal esophageal epithelium and HET-1A cells (derived from normal squamous epithelium) show high levels of Beclin-1, but lower levels of Beclin-1 were found in BE and EAC cell lines (CP-A, CP-C, and OE33). Acute exposure to DCA led to increased Beclin-1 expression and increased autophagy as evaluated by electron microscopy and counting percentage of GFP-LC3-positive BE cells with punctate pattern. In contrast, chronic exposure to DCA did not result in the alteration of Beclin-1 levels or autophagy. In summary, these data suggest that autophagy is initially activated in response to bile acids, but chronic exposure to bile acids leads to decreased Beclin-1 expression and autophagy resistance.
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Affiliation(s)
| | | | | | | | | | - George S. Watts
- 2Arizona Cancer Center, University of Arizona, Tucson, Arizona; and
| | - Xiaoxin Chen
- 3Cancer Research Program, Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, Durham, North Carolina
| | - Katerina Dvorak
- 1Department of Cellular and Molecular Medicine and ,2Arizona Cancer Center, University of Arizona, Tucson, Arizona; and
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Payne CM, Holubec H, Crowley-Skillicorn C, Nguyen H, Bernstein H, Wilcox G, Bernstein C. Maspin is a deoxycholate-inducible, anti-apoptotic stress-response protein differentially expressed during colon carcinogenesis. Clin Exp Gastroenterol 2011; 4:239-53. [PMID: 22162927 PMCID: PMC3234125 DOI: 10.2147/ceg.s24093] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Increased maspin expression in the colon is related to colon cancer risk and patient survival. Maspin is induced by the hydrophobic bile acid, deoxycholate (DOC), which is an endogenous carcinogen and inducer of oxidative stress and DNA damage in the colon. Persistent exposure of colon epithelial cells, in vitro, to high physiologic levels of DOC results in increased constitutive levels of maspin protein expression associated with the development of apoptosis resistance. When an apoptosis-resistant colon epithelial cell line (HCT-116RC) developed in the authors' laboratory was treated with a maspin-specific siRNA probe, there was a statistically significant increase in apoptosis compared to treatment with an siRNA control probe. These results indicate, for the first time, that maspin is an anti-apoptotic protein in the colon. Immunohistochemical evaluation of maspin expression in human colonic epithelial cells during sporadic colon carcinogenesis (131 human tissues evaluated) indicated a statistically significant increase in maspin protein expression beginning at the polyp stage of carcinogenesis. There was no statistically significant difference in maspin expression between hyperplastic/adenomatous polyps and colonic adenocarcinomas. The absence of "field defects" in the non-neoplastic colonic mucosa of patients with colonic neoplasia indicates that maspin may drive the growth of tumors, in part, through its anti-apoptotic function.
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Affiliation(s)
- Claire M Payne
- Department of Cellular and Molecular Medicine, College of Medicine, University of Arizona
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15
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Zhang Y, Csanaky IL, Lehman-McKeeman LD, Klaassen CD. Loss of organic anion transporting polypeptide 1a1 increases deoxycholic acid absorption in mice by increasing intestinal permeability. Toxicol Sci 2011; 124:251-60. [PMID: 21914718 DOI: 10.1093/toxsci/kfr236] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Deoxycholic acid (DCA) is a known hepatotoxicant, a tissue tumor promoter, and has been implicated in colorectal cancer. Male mice are more susceptible to DCA toxicity than female mice. Organic anion transporting polypeptide 1a1 (Oatp1a1), which is known to transport bile acids (BAs) in vitro, is predominantly expressed in livers of male mice. In addition, the concentrations of DCA and its taurine conjugate (TDCA) are increased in serum of Oatp1a1-null mice. To investigate whether Oatp1a1 contributes to the gender difference in DCA toxicity in mice, wild-type (WT) and Oatp1a1-null mice were fed a 0.3% DCA diet for 7 days. After feeding DCA, Oatp1a1-null mice had 30-fold higher concentrations of DCA in both serum and livers than WT mice. Feeding DCA caused more hepatotoxcity in Oatp1a1-null mice than WT mice. After feeding DCA, Oatp1a1-null mice expressed higher BA efflux-transporters (bile salt-export pump, organic solute transporter (Ost)α/β, and multidrug resistance-associated protein [Mrp]2) and lower BA-synthetic enzymes (cytochrome P450 [Cyp]7a1, 8b1, 27a1, and 7b1) in livers than WT mice. Intravenous administration of DCA and TDCA showed that lack of Oatp1a1 does not decrease the plasma elimination of DCA or TDCA. After feeding DCA, the concentrations of DCA in ileum and colon tissues are higher in Oatp1a1-null than in WT mice. In addition, Oatp1a1-null mice have enhanced intestinal permeability. Taken together, the current data suggest that Oatp1a1 does not mediate the hepatic uptake of DCA or TDCA, but lack of Oatp1a1 increases intestinal permeability and thus enhances the absorption of DCA in mice.
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Affiliation(s)
- Youcai Zhang
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
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Payne CM, Crowley-Skillicorn C, Bernstein C, Holubec H, Bernstein H. Molecular and cellular pathways associated with chromosome 1p deletions during colon carcinogenesis. Clin Exp Gastroenterol 2011; 4:75-119. [PMID: 21753893 PMCID: PMC3132853 DOI: 10.2147/ceg.s17114] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Indexed: 11/23/2022] Open
Abstract
Chromosomal instability is a major pathway of sporadic colon carcinogenesis. Chromosome arm 1p appears to be one of the "hot spots" in the non-neoplastic mucosa that, when deleted, is associated with the initiation of carcinogenesis. Chromosome arm 1p contains genes associated with DNA repair, spindle checkpoint function, apoptosis, multiple microRNAs, the Wnt signaling pathway, tumor suppression, antioxidant activities, and defense against environmental toxins. Loss of 1p is dangerous since it would likely contribute to genomic instability leading to tumorigenesis. The 1p deletion-associated colon carcinogenesis pathways are reviewed at the molecular and cellular levels. Sporadic colon cancer is strongly linked to a high-fat/low-vegetable/low-micronutrient, Western-style diet. We also consider how selected dietary-related compounds (eg, excess hydrophobic bile acids, and low levels of folic acid, niacin, plant-derived antioxidants, and other modulatory compounds) might affect processes leading to chromosomal deletions, and to the molecular and cellular pathways specifically altered by chromosome 1p loss.
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Affiliation(s)
- Claire M Payne
- Department of Cell Biology and Anatomy, College of Medicine, University of Arizona Tucson, AZ, USA
| | | | - Carol Bernstein
- Department of Cell Biology and Anatomy, College of Medicine, University of Arizona Tucson, AZ, USA
| | - Hana Holubec
- Department of Cell Biology and Anatomy, College of Medicine, University of Arizona Tucson, AZ, USA
| | - Harris Bernstein
- Department of Cell Biology and Anatomy, College of Medicine, University of Arizona Tucson, AZ, USA
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Bernstein C, Holubec H, Bhattacharyya AK, Nguyen H, Payne CM, Zaitlin B, Bernstein H. Carcinogenicity of deoxycholate, a secondary bile acid. Arch Toxicol 2011; 85:863-71. [PMID: 21267546 PMCID: PMC3149672 DOI: 10.1007/s00204-011-0648-7] [Citation(s) in RCA: 250] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Accepted: 01/10/2011] [Indexed: 12/19/2022]
Abstract
High dietary fat causes increased bile acid secretion into the gastrointestinal tract and is associated with colon cancer. Since the bile acid deoxycholic acid (DOC) is suggested to be important in colon cancer etiology, this study investigated whether DOC, at a high physiologic level, could be a colon carcinogen. Addition of 0.2% DOC for 8-10 months to the diet of 18 wild-type mice induced colonic tumors in 17 mice, including 10 with cancers. Addition of the antioxidant chlorogenic acid at 0.007% to the DOC-supplemented diet significantly reduced tumor formation. These results indicate that a high fat diet in humans, associated with increased risk of colon cancer, may have its carcinogenic potential mediated through the action of bile acids, and that some dietary anti-oxidants may ameliorate this carcinogenicity.
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Affiliation(s)
- Carol Bernstein
- Department of Cell Biology and Anatomy, College of Medicine, University of Arizona, Tucson, AZ 85724-5044, USA.
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Philipp B. Bacterial degradation of bile salts. Appl Microbiol Biotechnol 2010; 89:903-15. [PMID: 21088832 DOI: 10.1007/s00253-010-2998-0] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 10/29/2010] [Accepted: 10/30/2010] [Indexed: 12/11/2022]
Abstract
Bile salts are surface-active steroid compounds. Their main physiological function is aiding the digestion of lipophilic nutrients in intestinal tracts of vertebrates. Many bacteria are capable of transforming and degrading bile salts in the digestive tract and in the environment. Bacterial bile salt transformation and degradation is of high ecological relevance and also essential for the biotechnological production of steroid drugs. While biotechnological aspects have been reviewed many times, the physiological, biochemical and genetic aspects of bacterial bile salt transformation have been neglected. This review provides an overview of the reaction sequence of bile salt degradation and on the respective enzymes and genes exemplified with the degradation pathway of the bile salt cholate. The physiological adaptations for coping with the toxic effects of bile salts, recent biotechnological applications and ecological aspects of bacterial bile salt metabolism are also addressed. As the pathway for bile salt degradation merges with metabolic pathways for bacterial transformation of other steroids, such as testosterone and cholesterol, this review provides helpful background information for metabolic engineering of steroid-transforming bacteria in general.
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Affiliation(s)
- Bodo Philipp
- Mikrobielle Ökologie, Fachbereich Biologie, Universität Konstanz, Fach M654, 78457 Konstanz, Germany.
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Bernstein H, Bernstein C, Payne CM, Dvorak K. Bile acids as endogenous etiologic agents in gastrointestinal cancer. World J Gastroenterol 2009; 15:3329-40. [PMID: 19610133 PMCID: PMC2712893 DOI: 10.3748/wjg.15.3329] [Citation(s) in RCA: 202] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Bile acids are implicated as etiologic agents in cancer of the gastrointestinal (GI) tract, including cancer of the esophagus, stomach, small intestine, liver, biliary tract, pancreas and colon/rectum. Deleterious effects of bile acid exposure, likely related to carcinogenesis, include: induction of reactive oxygen and reactive nitrogen species; induction of DNA damage; stimulation of mutation; induction of apoptosis in the short term, and selection for apoptosis resistance in the long term. These deleterious effects have, so far, been reported most consistently in relation to esophageal and colorectal cancer, but also to some extent in relation to cancer of other organs. In addition, evidence is reviewed for an association of increased bile acid exposure with cancer risk in human populations, in specific human genetic conditions, and in animal experiments. A model for the role of bile acids in GI carcinogenesis is presented from a Darwinian perspective that offers an explanation for how the observed effects of bile acids on cells contribute to cancer development.
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