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Agarwal M, Roth K, Yang Z, Sharma R, Maddipati K, Westrick J, Petriello MC. Loss of flavin-containing monooxygenase 3 modulates dioxin-like polychlorinated biphenyl 126-induced oxidative stress and hepatotoxicity. ENVIRONMENTAL RESEARCH 2024; 250:118492. [PMID: 38373550 PMCID: PMC11102846 DOI: 10.1016/j.envres.2024.118492] [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: 12/21/2023] [Revised: 02/09/2024] [Accepted: 02/13/2024] [Indexed: 02/21/2024]
Abstract
Dioxin-like pollutants (DLPs), such as polychlorinated biphenyl 126 (PCB 126), are synthetic chemicals classified as persistent organic pollutants. They accumulate in adipose tissue and have been linked to cardiometabolic disorders, including fatty liver disease. The toxicity of these compounds is associated with activation of the aryl hydrocarbon receptor (Ahr), leading to the induction of phase I metabolizing enzyme cytochrome P4501a1 (Cyp1a1) and the subsequent production of reactive oxygen species (ROS). Recent research has shown that DLPs can also induce the xenobiotic detoxification enzyme flavin-containing monooxygenase 3 (FMO3), which plays a role in metabolic homeostasis. We hypothesized whether genetic deletion of Fmo3 could protect mice, particularly in the liver, where Fmo3 is most inducible, against PCB 126 toxicity. To test this hypothesis, male C57BL/6 wild-type (WT) mice and Fmo3 knockout (Fmo3 KO) mice were exposed to PCB 126 or vehicle (safflower oil) during a 12-week study, at weeks 2 and 4. Various analyses were performed, including hepatic histology, RNA-sequencing, and quantitation of PCB 126 and F2-isoprostane concentrations. The results showed that PCB 126 exposure caused macro and microvesicular fat deposition in WT mice, but this macrovesicular fatty change was absent in Fmo3 KO mice. Moreover, at the pathway level, the hepatic oxidative stress response was significantly different between the two genotypes, with the induction of specific genes observed only in WT mice. Notably, the most abundant F2-isoprostane, 8-iso-15-keto PGE2, increased in WT mice in response to PCB 126 exposure. The study's findings also demonstrated that hepatic tissue concentrations of PCB 126 were higher in WT mice compared to Fmo3 KO mice. In summary, the absence of FMO3 in mice led to a distinctive response to dioxin-like pollutant exposure in the liver, likely due to alterations in lipid metabolism and storage, underscoring the complex interplay of genetic factors in the response to environmental toxins.
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Affiliation(s)
- Manisha Agarwal
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, MI, 48202, USA; Institute of Environmental Health Sciences, Wayne State University, Detroit, MI, 48202, USA
| | - Katherine Roth
- Institute of Environmental Health Sciences, Wayne State University, Detroit, MI, 48202, USA
| | - Zhao Yang
- Institute of Environmental Health Sciences, Wayne State University, Detroit, MI, 48202, USA
| | - Rahul Sharma
- Institute of Environmental Health Sciences, Wayne State University, Detroit, MI, 48202, USA
| | - Krishnarao Maddipati
- Department of Pathology, Lipidomic Core Facility, Wayne State University, Detroit, MI, 48202, USA
| | - Judy Westrick
- Department of Chemistry, Lumigen Instrumentation Center, Wayne State University, Detroit, MI, 48202, USA
| | - Michael C Petriello
- Department of Pharmacology, School of Medicine, Wayne State University, Detroit, MI, 48202, USA; Institute of Environmental Health Sciences, Wayne State University, Detroit, MI, 48202, USA.
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Wei Y, Zhou G, Lv G, Wei W, Shera L, Lin H, Chen J, Kang D. PCB169 exposure aggravated the development of non-alcoholic fatty liver in high-fat diet-induced male C57BL/6 mice. Front Nutr 2024; 11:1350146. [PMID: 38779445 PMCID: PMC11110572 DOI: 10.3389/fnut.2024.1350146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 04/22/2024] [Indexed: 05/25/2024] Open
Abstract
Polychlorinated biphenyls (PCBs) are lipophilic environmental toxicants. Epidemiological studies have established a link between PCBs and both metabolic syndrome and nonalcoholic fatty liver disease (NAFLD). Multiple studies have reported that exposure to both PCB156 and PCB126 among the 12 dioxin-like PCBs leads to the development of NAFLD. However, studies to elucidate whether PCB169 induces the development of NAFLD by constructing in vivo models have not been reported. Therefore, we evaluated the effects of exposure to PCB169 (5 mg/kg-bw) on hepatic lipid metabolism in C57BL/6 mice from control diet and high-fat diet cohorts. The results showed that PCB169 exposure reduced body weight and intraperitoneal fat mass in mice on the control diet, but the liver lipid levels were significantly increased, exacerbating NAFLD in mice on a high-fat diet. Through transcriptomics studies, it was found that PCB169 exposure induced significant up-regulation of Pparγ, Fasn, and Aacs genes involved in hepatic lipogenesis, as well as remarkable up-regulation of Hmgcr, Lss, and Sqle genes involved in cholesterol synthesis. Additionally, there was notable down-regulation of Pparα and Cpt1 genes involved in lipid β-oxidation, leading to abnormal lipid accumulation in the liver. In addition, we found that PCB169 exposure significantly activated the Arachidonic acid metabolism, PPAR signaling pathway, Metabolism of xenobiotics by cytochrome P450, and Retinol metabolism pathways, and so on. Our study suggests that PCB169 can modify gene expression related to lipid metabolism, augument lipid accumulation in the liver, and further contribute to the development of NAFLD, thereby revealing the detrimental effects associated with PCB exposure on animal growth and metabolism.
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Affiliation(s)
| | | | | | | | | | | | - Jinjun Chen
- Department of Veterinary Medicine, College of Coastal Agriculture, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Danju Kang
- Department of Veterinary Medicine, College of Coastal Agriculture, Guangdong Ocean University, Zhanjiang, Guangdong, China
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Hjazi A, Hsu CY, Al-Attar WM, Almajidi YQ, Hussien BM, Alzahrani AA, Kareem AK, Abdulhussien Alazbjee AA, Meng X. The association of exposure to polychlorinated biphenyls with lipid profile and liver enzymes in umbilical cord blood samples. CHEMOSPHERE 2024; 350:141096. [PMID: 38176591 DOI: 10.1016/j.chemosphere.2023.141096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 11/24/2023] [Accepted: 12/30/2023] [Indexed: 01/06/2024]
Abstract
Evidence on prenatal exposure to polychlorinated biphenyls (PCBs) and its effects on newborns and potential biological mechanisms is not well defined yet. Therefore, this study aimed to examine whether PCBs are associated with lipid profile and non-invasive markers of hepatocyte injuries in samples of blood obtained from the umbilical cord. This study included 450 mothers-newborn pairs. Umbilical levels of PCBs were measured using Gas Chromatography/Mass Spectrophotometry (GC/MS). Lipid profile including low-density lipoprotein (LDL-C), total cholesterol (TC), triglycerides (TG), and high-density lipoprotein (HDL-C), as well as liver enzymes i.e., alanine amino transferase (ALT), aspartate amino transferase (AST), γ-glutamyl-transferase (GGT) and alkaline phosphatase (ALP) were determined from umbilical cord blood samples. Quantile g-computation analysis was applied to evaluate the collective influence of PCBs on both lipid profiles and liver enzymes, along with the impact of lipid profiles on liver enzymes. Exposure to the mixture of PCBs was significantly associated with increases in ALP, AST, ALT, and GGT levels in cord blood samples, with increments of 90.38 U/L (95%CI: 65.08, 115.70, p < 0.01), 11.88 U/L (95%CI: 9.03, 14.74, p < 0.01), 2.19 U/L (95%CI:1.43, 2.94, p < 0.01), and 50.67 U/L (95%CI: 36.32, 65.03, p < 0.01), respectively. Additionally, combined PCBs exposure was correlated with significant increases in umbilical TG, TC, and LDL-C levels, with values of 3.97 mg/dL (95%CI: 0.86, 7.09, p = 0.01), 6.30 mg/dL (95%CI: 2.98, 9.61, p < 0.01), and 4.63 mg/dL (95%CI: 2.04, 7.23, p < 0.01) respectively. Exposure to the mixture of lipids was linked to elevated levels of AST and GGT in umbilical cord blood samples. Furthermore, a noteworthy mediating role of TC and LDL-C was observed in the association between total PCBs exposure and umbilical cord blood liver enzyme levels. Overall our findings suggested that higher levels of umbilical cord blood PCBs and lipid profile could affect liver function in newborns.
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Affiliation(s)
- Ahmed Hjazi
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Prince Sattam bin Abdulaziz University, Al-Kharj, 11942, Saudi Arabia
| | - Chou-Yi Hsu
- Department of Pharmacy, Chia Nan University of Pharmacy and Science, Tainan, Taiwan
| | | | - Yasir Qasim Almajidi
- Lecturer Dr and Dean Assistant of Baghdad College of Medical Sciences-department of Pharmacy (pharmaceutics), Baghdad, Iraq
| | - Beneen M Hussien
- Medical Laboratory Technology Department, College of Medical Technology, The Islamic University, Najaf, Iraq; Medical Laboratory Technology Department, College of Medical Technology, the Islamic University of Al Diwaniyah, Al Diwaniyah, Iraq; Medical Laboratory Technology Department, College of Medical Technology, the Islamic University of Babylon, Babylon, Iraq
| | | | - A K Kareem
- Biomedical Engineering Department, College of Engineering and Technologies, Al-Mustaqbal University, Hillah, Iraq
| | | | - Xuan Meng
- Hepatobiliary Surgery Department, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021, China; Hepatobiliary Surgery Department, Hebei Cancer Hospital, Chinese Academy of Medical Sciences, Langfang, Hebei, 065001, China; Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy, Cancer Institute, Xuzhou Medical College, Xuzhou, Jiangsu, 221002, China.
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Wang Z, Zhou Y, Xiao X, Liu A, Wang S, Preston RJS, Zaytseva YY, He G, Xiao W, Hennig B, Deng P. Inflammation and cardiometabolic diseases induced by persistent organic pollutants and nutritional interventions: Effects of multi-organ interactions. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 339:122756. [PMID: 37844865 PMCID: PMC10842216 DOI: 10.1016/j.envpol.2023.122756] [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: 08/18/2023] [Revised: 10/11/2023] [Accepted: 10/13/2023] [Indexed: 10/18/2023]
Abstract
The development and outcome of inflammatory diseases are associated with genetic and lifestyle factors, which include chemical and nonchemical stressors. Persistent organic pollutants (POPs) are major groups of chemical stressors. For example, dioxin-like polychlorinated biphenyls (PCBs), per- and polyfluoroalkyl substances (PFASs), and polybrominated diphenyl ethers (PBDEs) are closely associated with the incidence of inflammatory diseases. The pathology of environmental chemical-mediated inflammatory diseases is complex and may involve disturbances in multiple organs, including the gut, liver, brain, vascular tissues, and immune systems. Recent studies suggested that diet-derived nutrients (e.g., phytochemicals, vitamins, unsaturated fatty acids, dietary fibers) could modulate environmental insults and affect disease development, progression, and outcome. In this article, mechanisms of environmental pollutant-induced inflammation and cardiometabolic diseases are reviewed, focusing on multi-organ interplays and highlighting recent advances in nutritional strategies to improve the outcome of cardiometabolic diseases associated with environmental exposures. In addition, advanced system biology approaches are discussed, which present unique opportunities to unveil the complex interactions among multiple organs and to fuel the development of precision intervention strategies in exposed individuals.
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Affiliation(s)
- Zhongmin Wang
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, China; Irish Centre for Vascular Biology, School of Pharmacy & Biomolecular Sciences, Royal College of Surgeons in Ireland, Ireland
| | - Yixuan Zhou
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, China
| | - Xia Xiao
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, China
| | - Aowen Liu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, China
| | - Shengnan Wang
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, China
| | - Roger J S Preston
- Irish Centre for Vascular Biology, School of Pharmacy & Biomolecular Sciences, Royal College of Surgeons in Ireland, Ireland
| | - Yekaterina Y Zaytseva
- Superfund Research Center, University of Kentucky, Lexington, KY, USA; Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, USA
| | - Guangzhao He
- Department of Pharmacy, Changzhou Cancer Hospital, Soochow University, Changzhou, Jiangsu, China
| | - Wenjin Xiao
- Department of Endocrinology, Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Bernhard Hennig
- Superfund Research Center, University of Kentucky, Lexington, KY, USA; Department of Animal and Food Sciences, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, USA
| | - Pan Deng
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, China.
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Head KZ, Bolatimi OE, Gripshover TC, Tan M, Li Y, Audam TN, Jones SP, Klinge CM, Cave MC, Wahlang B. Investigating the effects of long-term Aroclor 1260 exposure on fatty liver disease in a diet-induced obesity mouse model. FRONTIERS IN GASTROENTEROLOGY (LAUSANNE, SWITZERLAND) 2023; 2:1180712. [PMID: 37426695 PMCID: PMC10327714 DOI: 10.3389/fgstr.2023.1180712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
Introduction Polychlorinated biphenyls (PCBs) are persistent environmental toxicants that have been implicated in numerous health disorders including liver diseases such as non-alcoholic fatty liver disease (NAFLD). Toxicant-associated NAFLD, also known as toxicant-associated fatty liver disease (TAFLD), consists of a spectrum of disorders ranging from steatosis and steatohepatitis to fibrosis and hepatocellular carcinoma. Previously, our group demonstrated that 12-week exposure to the PCB mixture, Aroclor 1260, exacerbated steatohepatitis in high-fat diet (HFD)-fed mice; however, the longer-term effects of PCBs on TAFLD remain to be elucidated. This study aims to examine the longer-term effects of Aroclor 1260 (>30 weeks) in a diet-induced obesity model to better understand how duration of exposure can impact TAFLD. Methods Male C57BL/6 mice were exposed to Aroclor 1260 (20 mg/kg) or vehicle control by oral gavage at the beginning of the study period and fed either a low-fat diet (LFD) or HFD throughout the study period. Results Aroclor 1260 exposure (>30 weeks) led to steatohepatitis only in LFD-fed mice. Several Aroclor 1260 exposed LFD-fed mice also developed hepatocellular carcinoma (25%), which was absent in HFD-fed mice. The LFD+Aroclor1260 group also exhibited decreased hepatic Cyp7a1 expression and increased pro-fibrotic Acta2 expression. In contrast, longer term Aroclor 1260 exposure in conjunction with HFD did not exacerbate steatosis or inflammatory responses beyond those observed with HFD alone. Further, hepatic xenobiotic receptor activation by Aroclor 1260 was absent at 31 weeks post exposure, suggesting PCB redistribution to the adipose and other extra-hepatic tissues with time. Discussion Overall, the results demonstrated that longer-term PCB exposure worsened TAFLD outcomes independent of HFD feeding and suggests altered energy metabolism as a potential mechanism fueling PCB mediated toxicity without dietary insult. Additional research exploring mechanisms for these longer-term PCB mediated toxicity in TAFLD is warranted.
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Affiliation(s)
- Kimberly Z. Head
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, United States
- The Hepatobiology and Toxicology Center, University of Louisville, Louisville, KY, United States
| | - Oluwanifemi E. Bolatimi
- Department of Pharmacology and Toxicology, School of Medicine, University of Louisville, Louisville, KY, United States
| | - Tyler C. Gripshover
- Department of Pharmacology and Toxicology, School of Medicine, University of Louisville, Louisville, KY, United States
| | - Min Tan
- Department of Surgery, School of Medicine, University of Louisville, Louisville, KY, United States
| | - Yan Li
- Department of Surgery, School of Medicine, University of Louisville, Louisville, KY, United States
| | - Timothy N. Audam
- Center for Cardiometabolic Science, Department of Medicine, Division of Environmental Medicine, Christina Lee Brown Envirome Institute, University of Louisville, Louisville, KY, United States
| | - Steven P. Jones
- Center for Cardiometabolic Science, Department of Medicine, Division of Environmental Medicine, Christina Lee Brown Envirome Institute, University of Louisville, Louisville, KY, United States
| | - Carolyn M. Klinge
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Louisville, Louisville, KY, United States
- The Center for Integrative Environmental Health Sciences, University of Louisville, Louisville, KY, United States
| | - Matthew C. Cave
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, United States
- The Hepatobiology and Toxicology Center, University of Louisville, Louisville, KY, United States
- Department of Pharmacology and Toxicology, School of Medicine, University of Louisville, Louisville, KY, United States
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Louisville, Louisville, KY, United States
- The Center for Integrative Environmental Health Sciences, University of Louisville, Louisville, KY, United States
- University of Louisville (UofL) Superfund Research Center, University of Louisville, Louisville, KY, United States
- Robley Rex Department of Veterans Affairs Medical Center, Louisville, KY, United States
| | - Banrida Wahlang
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, United States
- The Hepatobiology and Toxicology Center, University of Louisville, Louisville, KY, United States
- The Center for Integrative Environmental Health Sciences, University of Louisville, Louisville, KY, United States
- University of Louisville (UofL) Superfund Research Center, University of Louisville, Louisville, KY, United States
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Gripshover TC, Wahlang B, Head KZ, Young JL, Luo J, Mustafa MT, Kirpich IA, Cave MC. The environmental pollutant, polychlorinated biphenyl 126, alters liver function in a rodent model of alcohol-associated liver disease. ALCOHOL, CLINICAL & EXPERIMENTAL RESEARCH 2023; 47:60-75. [PMID: 36377258 PMCID: PMC9974797 DOI: 10.1111/acer.14976] [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: 06/03/2022] [Revised: 11/08/2022] [Accepted: 11/10/2022] [Indexed: 11/16/2022]
Abstract
BACKGROUND The prevalence of alcohol-associated liver disease (ALD), a subtype of fatty liver disease (FLD), continues to rise. ALD is a major cause of preventable death. Polychlorinated biphenyl (PCB) 126 is an environmentally relevant, dioxin-like pollutant whose negative metabolic effects have been well documented. In human and animal studies, PCB has been associated with the severity of nonalcoholic fatty liver disease (NAFLD). However, few studies have investigated whether exposures to environmental toxicants can worsen ALD. Thus, the objective of the current study was to develop an alcohol-plus-toxicant model to study how an environmental pollutant, PCB 126, impacts rodent ALD pathology. METHODS Briefly, male C57BL/6J mice were exposed to 0.2 mg/kg PCB 126 or corn oil vehicle four days prior to ethanol feeding using the chronic-binge (10-plus-one) model. RESULTS Concentrations of macromolecules, including hepatic lipids, carbohydrates, and protein (albumin) were impacted. Exposure to PCB 126 exacerbated hepatic steatosis and hepatomegaly in mice exposed to the chemical and fed an ethanol diet. Gene expression and the analysis of blood chemistry showed a potential net increase and retention of hepatic lipids and reductions in lipid oxidation and clearance capabilities. Depletion of glycogen and glucose was evident, which contributes to disease progression by generating systemic malnutrition. Granulocytic immune infiltrates were present but driven solely by ethanol feeding. Hepatic albumin gene expression and plasma levels were decreased by ~50% indicating a potential compromise of liver function. Finally, gene expression analyses indicated that the aryl hydrocarbon receptor and constitutive androstane receptor were activated by PCB 126 and ethanol, respectively. CONCLUSIONS Various environmental toxicants are known to modify or enhance FLD in high-fat diet models. Findings from the present study suggest that they interact with other lifestyle factors such as alcohol consumption to reprogram intermediary metabolism resulting in exacerbated ethanol-associated systemic malnutrition in ALD.
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Affiliation(s)
- Tyler C. Gripshover
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40202, USA
- Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY 40202, USA
- University of Louisville Superfund Research Program, University of Louisville, Louisville, KY 40202, USA
| | - Banrida Wahlang
- Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY 40202, USA
- Hepatobiology & Toxicology COBRE, University of Louisville School of Medicine, Louisville, KY 40202, USA
- University of Louisville Alcohol Research Center, University of Louisville, Louisville, KY 40202, USA
- University of Louisville Superfund Research Program, University of Louisville, Louisville, KY 40202, USA
| | - Kimberly Z. Head
- Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY 40202, USA
- Hepatobiology & Toxicology COBRE, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Jamie L. Young
- Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY 40202, USA
| | - Jianzhu Luo
- Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY 40202, USA
| | - Muhammad T. Mustafa
- The Center for Integrative Environmental Health Sciences, University of Louisville, Louisville, KY, 40202, USA
| | - Irina A. Kirpich
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40202, USA
- Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY 40202, USA
- Hepatobiology & Toxicology COBRE, University of Louisville School of Medicine, Louisville, KY 40202, USA
- University of Louisville Alcohol Research Center, University of Louisville, Louisville, KY 40202, USA
| | - Matthew C. Cave
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40202, USA
- Department of Biochemistry and Molecular Genetics, University of Louisville School of Medicine, Louisville, KY 40202, USA
- Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY 40202, USA
- The Robley Rex Veterans Affairs Medical Center, Louisville, KY 40206, USA
- The Liver Transplant Program at UofL Health - Jewish Hospital Trager Transplant Center, Louisville, KY 40202 USA
- Hepatobiology & Toxicology COBRE, University of Louisville School of Medicine, Louisville, KY 40202, USA
- University of Louisville Alcohol Research Center, University of Louisville, Louisville, KY 40202, USA
- University of Louisville Superfund Research Program, University of Louisville, Louisville, KY 40202, USA
- The Center for Integrative Environmental Health Sciences, University of Louisville, Louisville, KY, 40202, USA
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Petri BJ, Piell KM, Wahlang B, Head KZ, Andreeva K, Rouchka EC, Cave MC, Klinge CM. Polychlorinated biphenyls alter hepatic m6A mRNA methylation in a mouse model of environmental liver disease. ENVIRONMENTAL RESEARCH 2023; 216:114686. [PMID: 36341798 PMCID: PMC10120843 DOI: 10.1016/j.envres.2022.114686] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 09/30/2022] [Accepted: 10/25/2022] [Indexed: 05/21/2023]
Abstract
Exposure to polychlorinated biphenyls (PCBs) has been associated with liver injury in human cohorts and with nonalcoholic steatohepatitis (NASH) in mice fed a high fat diet (HFD). N (6)-methyladenosine (m6A) modification of mRNA regulates transcript fate, but the contribution of m6A modification on the regulation of transcripts in PCB-induced steatosis and fibrosis is unknown. This study tested the hypothesis that PCB and HFD exposure alters the levels of m6A modification in transcripts that play a role in NASH in vivo. Male C57Bl6/J mice were fed a HFD (12 wks) and administered a single oral dose of Aroclor1260, PCB126, or Aroclor1260 + PCB126. Genome-wide identification of m6A peaks was accomplished by m6A mRNA immunoprecipitation sequencing (m6A-RIP) and the mRNA transcriptome identified by RNA-seq. Exposure of HFD-fed mice to Aroclor1260 decreased the number of m6A peaks and m6A-containing genes relative to PCB vehicle control whereas PCB126 or the combination of Aroclor1260 + PCB126 increased m6A modification frequency. ∼41% of genes had one m6A peak and ∼49% had 2-4 m6A peaks. 117 m6A peaks were common in the four experimental groups. The Aroclor1260 + PCB126 exposure group showed the highest number (52) of m6A-peaks. qRT-PCR confirmed enrichment of m6A-containing fragments of the Apob transcript with PCB exposure. A1cf transcript abundance, m6A peak count, and protein abundance was increased with Aroclor1260 + PCB126 co-exposure. Irrespective of the PCB type, all PCB groups exhibited enriched pathways related to lipid/lipoprotein metabolism and inflammation through the m6A modification. Integrated analysis of m6A-RIP-seq and mRNA-seq identified 242 differentially expressed genes (DEGs) with increased or reduced number of m6A peaks. These data show that PCB exposure in HFD-fed mice alters the m6A landscape offering an additional layer of regulation of gene expression affecting a subset of gene responses in NASH.
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Affiliation(s)
- Belinda J Petri
- Department of Biochemistry & Molecular Genetics, University of Louisville School of Medicine, Louisville, KY, 40292, USA
| | - Kellianne M Piell
- Department of Biochemistry & Molecular Genetics, University of Louisville School of Medicine, Louisville, KY, 40292, USA
| | - Banrida Wahlang
- University of Louisville Center for Integrative Environmental Health Sciences (CIEHS), USA; University of Louisville Hepatobiology and Toxicology Center, USA; The University of Louisville Superfund Research Center, USA; Division of Gastroenterology, Hepatology & Nutrition, Department of Medicine, University of Louisville School of Medicine, USA
| | - Kimberly Z Head
- University of Louisville Hepatobiology and Toxicology Center, USA
| | - Kalina Andreeva
- KY INBRE Bioinformatics Core, University of Louisville, USA; Department of Genetics, Stanford University School of Medicine, Palo Alto, CA, 94304, USA
| | - Eric C Rouchka
- Department of Biochemistry & Molecular Genetics, University of Louisville School of Medicine, Louisville, KY, 40292, USA; KY INBRE Bioinformatics Core, University of Louisville, USA
| | - Matthew C Cave
- Department of Biochemistry & Molecular Genetics, University of Louisville School of Medicine, Louisville, KY, 40292, USA; Division of Gastroenterology, Hepatology & Nutrition, Department of Medicine, University of Louisville School of Medicine, USA
| | - Carolyn M Klinge
- Department of Biochemistry & Molecular Genetics, University of Louisville School of Medicine, Louisville, KY, 40292, USA; University of Louisville Center for Integrative Environmental Health Sciences (CIEHS), USA.
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Kim HY, Park CH, Park JB, Ko K, Lee MH, Chung J, Yoo YH. Hepatic STAMP2 alleviates polychlorinated biphenyl-induced steatosis and hepatic iron overload in NAFLD models. ENVIRONMENTAL TOXICOLOGY 2022; 37:2223-2234. [PMID: 35616167 DOI: 10.1002/tox.23589] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 04/03/2022] [Accepted: 05/14/2022] [Indexed: 06/15/2023]
Abstract
Polychlorinated biphenyls (PCBs) have been associated with neurotoxicity, hepatoxicity, oncogenicity, and endocrine-disrupting effects. Although the recent studies have demonstrated that PCB exposure leads to nonalcoholic fatty liver disease (NAFLD), the underlying mechanism has remained unsolved. In this study, we examined the hepatic effects of a PCB mixture, Aroclor 1260, whose composition mimics human bioaccumulation patterns, and PCB 126 in C57BL/6 mice. Male C57Bl/6 mice were fed a standard diet or a 60% high-fat diet and exposed to Aroclor 1260 (10 mg/kg or 20 mg/kg) or PCB 126 (1 mg/kg or 5 mg/kg) by intraperitoneal injection for a total of four injections (2, 3, 4, and 5 weeks) for 6 weeks. In mice, both Aroclor 1260 and PCB 126-induced liver damage, hepatic steatosis and inflammation. We also observed that PCB exposure-induced hepatic iron overload (HIO). We previously demonstrated that hepatic six transmembrane protein of prostate 2 (STAMP2) may represent a suitable therapeutic target for NAFLD patients. Thus, we further examined whether hepatic STAMP2 is involved in PCB-induced NAFLD. We observed that hepatic STAMP2 was significantly decreased in PCB-induced NAFLD models in vivo and in vitro. Furthermore, overexpression of hepatic STAMP2 using an adenoviral delivery system resulted in improvement of PCB-induced steatosis and HIO in vivo and in vitro. Our findings indicate that enhancing hepatic STAMP2 expression represents a potential therapeutic avenue for the treatment of PCB exposure-induced NAFLD.
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Affiliation(s)
- Hye Young Kim
- Department of Anatomy and Cell Biology and BK21 program, Department of Translational Biomedical Science, Dong-A University College of Medicine, Busan, Republic of Korea
- Department of Oral Microbiology and Oral Genomics Research Center, School of Dentistry, Pusan National University, Busan, Republic of Korea
| | - Chul Hee Park
- Department of Anatomy and Cell Biology and BK21 program, Department of Translational Biomedical Science, Dong-A University College of Medicine, Busan, Republic of Korea
| | - Joon Beom Park
- Department of Anatomy and Cell Biology and BK21 program, Department of Translational Biomedical Science, Dong-A University College of Medicine, Busan, Republic of Korea
| | - Kangeun Ko
- Department of Anatomy and Cell Biology and BK21 program, Department of Translational Biomedical Science, Dong-A University College of Medicine, Busan, Republic of Korea
| | - Mi Hwa Lee
- Department of Anatomy and Cell Biology and BK21 program, Department of Translational Biomedical Science, Dong-A University College of Medicine, Busan, Republic of Korea
| | - Jin Chung
- Department of Oral Microbiology and Oral Genomics Research Center, School of Dentistry, Pusan National University, Busan, Republic of Korea
| | - Young Hyun Yoo
- Department of Anatomy and Cell Biology and BK21 program, Department of Translational Biomedical Science, Dong-A University College of Medicine, Busan, Republic of Korea
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9
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Petri BJ, Piell KM, Wahlang B, Head KZ, Andreeva K, Rouchka EC, Pan J, Rai SN, Cave MC, Klinge CM. Multiomics analysis of the impact of polychlorinated biphenyls on environmental liver disease in a mouse model. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2022; 94:103928. [PMID: 35803474 DOI: 10.1016/j.etap.2022.103928] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 06/27/2022] [Accepted: 07/03/2022] [Indexed: 06/15/2023]
Abstract
Exposure to high fat diet (HFD) and persistent organic pollutants including polychlorinated biphenyls (PCBs) is associated with liver injury in human populations and non-alcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH) in animal models. Previously, exposure of HFD-fed male mice to the non-dioxin-like (NDL) PCB mixture Aroclor1260, dioxin-like (DL) PCB126, or Aroclor1260 + PCB126 co-exposure caused toxicant-associated steatohepatitis (TASH) and differentially altered the liver proteome. Here unbiased mRNA and miRNA sequencing (mRNA- and miRNA- seq) was used to identify biological pathways altered in these liver samples. Fewer transcripts and miRs were up- or down- regulated by PCB126 or Aroclor1260 compared to the combination, suggesting that crosstalk between the receptors activated by these PCBs amplifies changes in the transcriptome. Pathway enrichment analysis identified "positive regulation of Wnt/β-catenin signaling" and "role of miRNAs in cell migration, survival, and angiogenesis" for differentially expressed mRNAs and miRNAs, respectively. We evaluated the five miRNAs increased in human plasma with PCB exposure and suspected TASH and found that miR-192-5p was increased with PCB exposure in mouse liver. Although we observed little overlap between differentially expressed mRNA transcripts and proteins, biological pathway-relevant PCB-induced miRNA-mRNA and miRNA-protein inverse relationships were identified that may explain protein changes. These results provide novel insights into miRNA and mRNA transcriptome changes playing direct and indirect roles in the functional protein pathways in PCB-related hepatic lipid accumulation, inflammation, and fibrosis in a mouse model of TASH and its relevance to human liver disease in exposed populations.
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Affiliation(s)
- Belinda J Petri
- Department of Biochemistry & Molecular Genetics, Center for Genetics and Molecular Medicine University of Louisville, Louisville, KY 40292, USA
| | - Kellianne M Piell
- Department of Biochemistry & Molecular Genetics, Center for Genetics and Molecular Medicine University of Louisville, Louisville, KY 40292, USA
| | - Banrida Wahlang
- University of Louisville Center for Integrative Environmental Health Sciences (CIEHS), USA; University of Louisville Hepatobiology and Toxicology Center, USA; The University of Louisville Superfund Research Center, USA; Division of Gastroenterology, Hepatology & Nutrition, Department of Medicine, University of Louisville School of Medicine, USA
| | - Kimberly Z Head
- University of Louisville Hepatobiology and Toxicology Center, USA
| | | | - Eric C Rouchka
- Department of Biochemistry & Molecular Genetics, Center for Genetics and Molecular Medicine University of Louisville, Louisville, KY 40292, USA; KY INBRE Bioinformatics Core, University of Louisville, USA
| | - Jianmin Pan
- Biostatistics and Bioinformatics Facility, Brown Cancer Center, USA
| | - Shesh N Rai
- University of Louisville Center for Integrative Environmental Health Sciences (CIEHS), USA; University of Louisville Hepatobiology and Toxicology Center, USA; Biostatistics and Bioinformatics Facility, Brown Cancer Center, USA
| | - Matthew C Cave
- Department of Biochemistry & Molecular Genetics, Center for Genetics and Molecular Medicine University of Louisville, Louisville, KY 40292, USA; University of Louisville Center for Integrative Environmental Health Sciences (CIEHS), USA; University of Louisville Hepatobiology and Toxicology Center, USA; The University of Louisville Superfund Research Center, USA; Division of Gastroenterology, Hepatology & Nutrition, Department of Medicine, University of Louisville School of Medicine, USA
| | - Carolyn M Klinge
- Department of Biochemistry & Molecular Genetics, Center for Genetics and Molecular Medicine University of Louisville, Louisville, KY 40292, USA; University of Louisville Center for Integrative Environmental Health Sciences (CIEHS), USA.
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10
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Jin J, Wahlang B, Thapa M, Head KZ, Hardesty JE, Srivastava S, Merchant ML, Rai SN, Prough RA, Cave MC. Proteomics and metabolic phenotyping define principal roles for the aryl hydrocarbon receptor in mouse liver. Acta Pharm Sin B 2021; 11:3806-3819. [PMID: 35024308 PMCID: PMC8727924 DOI: 10.1016/j.apsb.2021.10.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 09/23/2021] [Accepted: 09/28/2021] [Indexed: 12/20/2022] Open
Abstract
Dioxin-like molecules have been associated with endocrine disruption and liver disease. To better understand aryl hydrocarbon receptor (AHR) biology, metabolic phenotyping and liver proteomics were performed in mice following ligand-activation or whole-body genetic ablation of this receptor. Male wild type (WT) and Ahr–/– mice (Taconic) were fed a control diet and exposed to 3,3′,4,4′,5-pentachlorobiphenyl (PCB126) (61 nmol/kg by gavage) or vehicle for two weeks. PCB126 increased expression of canonical AHR targets (Cyp1a1 and Cyp1a2) in WT but not Ahr–/–. Knockouts had increased adiposity with decreased glucose tolerance; smaller livers with increased steatosis and perilipin-2; and paradoxically decreased blood lipids. PCB126 was associated with increased hepatic triglycerides in Ahr–/–. The liver proteome was impacted more so by Ahr–/– genotype than ligand-activation, but top gene ontology (GO) processes were similar. The PCB126-associated liver proteome was Ahr-dependent. Ahr principally regulated liver metabolism (e.g., lipids, xenobiotics, organic acids) and bioenergetics, but it also impacted liver endocrine response (e.g., the insulin receptor) and function, including the production of steroids, hepatokines, and pheromone binding proteins. These effects could have been indirectly mediated by interacting transcription factors or microRNAs. The biologic roles of the AHR and its ligands warrant more research in liver metabolic health and disease.
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Key Words
- AHR
- AHR, aryl hydrocarbon receptor
- ALT, alanine transaminase
- ANOVA, analysis of variance
- AST, aspartate transaminase
- AUC, area under the curve
- CAR, constitutive androstane receptor
- CD36, cluster of differentiation 36
- CYP, cytochrome P450
- EPF, enrichment by protein function
- Endocrine disruption
- Environmental liver disease
- FDR, false discovery rate
- FGF21, fibroblast growth factor 21
- GCR, glucocorticoid receptor
- GO, gene ontology
- H&E, hematoxylin-eosin
- HDL, high-density lipoprotein
- HFD, high fat diet
- IGF1, insulin-like growth factor 1
- IL-6, interleukin 6
- IPF, interaction by protein function
- LDL, low-density lipoprotein
- MCP-1, monocyte chemoattractant protein-1
- MUP, major urinary protein
- NAFLD, non-alcoholic fatty liver disease
- NFKBIA, nuclear factor kappa-inhibitor alpha
- Nonalcoholic fatty liver disease
- PAI-1, plasminogen activator inhibitor-1
- PCB, polychlorinated biphenyl
- PCB126
- PLIN2, perilipin-2
- PNPLA3, patatin-like phospholipase domain-containing protein 3
- PPARα, peroxisome proliferator-activated receptor alpha
- PXR, pregnane-xenobiotic receptor
- Perilipin-2
- Pheromones
- SGK1, serum/glucocorticoid regulated kinase
- TAFLD, toxicant-associated fatty liver disease
- TASH, toxicant-associated steatohepatitis
- TAT, tyrosine aminotransferase
- TMT, tandem mass tag
- VLDL, very low-density lipoprotein
- WT, wild type
- ZFP125, zinc finger protein 125
- miR, microRNA
- nHDLc, non-HDL cholesterol
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11
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Sen A, Anakk S. Jekyll and Hyde: nuclear receptors ignite and extinguish hepatic oxidative milieu. Trends Endocrinol Metab 2021; 32:790-802. [PMID: 34481730 PMCID: PMC8464172 DOI: 10.1016/j.tem.2021.07.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/26/2021] [Accepted: 07/27/2021] [Indexed: 12/21/2022]
Abstract
Nuclear receptors (NRs) are ligand-binding transcription factors that regulate gene networks and physiological responses. Often oxidative stress precedes the onset of liver diseases, and Nrf2 is a key regulator of antioxidant pathways. NRs crosstalk with Nrf2, since NR activation can influence the oxidative milieu by modulating reductive cellular processes. Diet and xenobiotics also regulate NR expression and activity, suggesting a feedback loop. Depending on the tissue context and cues, NRs either increase or decrease toxicity and oxidative damage. Many FDA-approved drugs target NRs, and one could potentially repurpose them to ameliorate reactive oxygen species (ROS). Here, we discuss how several NRs modulate oxidative stress subsequent to diet, organic pollutants, and drug-induced injury to the liver.
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Affiliation(s)
- Anushna Sen
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Sayeepriyadarshini Anakk
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
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12
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Guo J, Zhang S, Fang L, Huang J, Wang Q, Wang C, Chen M. In utero exposure to phenanthrene induces hepatic steatosis in F1 adult female mice. CHEMOSPHERE 2020; 258:127360. [PMID: 32554016 DOI: 10.1016/j.chemosphere.2020.127360] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 05/28/2020] [Accepted: 06/06/2020] [Indexed: 06/11/2023]
Abstract
Environmental pollutants are thought to be a risk factor for the prevalence of hepatic steatosis. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous, and human exposure is inevitable. In the present study, phenanthrene (Phe) was used as a representative PAH to investigate the effects of in utero exposure to PAH on hepatic lipid metabolism and the toxicological mechanism involved. Pregnant mice (C57BL/6J) were orally administered Phe (0, 60, 600 and 6000 μg kg-1 body weight) once every 3 days with 6 doses in total. F1 female mice aged 125 days showed significantly elevated hepatic lipid levels in the liver. The protein expression of hepatic peroxisome proliferator-activated receptors (PPARβ and PPARγ) and retinoid X receptors (RXRs) was upregulated; the transcription of genes related to lipogenesis, such as srebp1 (encoding sterol regulatory element binding proteins), acca (acetyl-CoA carboxylase), fasn (fatty acid synthase) and pcsk9 (proprotein convertase subtilisin/kexin type 9), showed an upregulation, while the mRNA levels of the lipolysis gene lcat (encoding lecithin cholesterol acyl transferase) were downregulated. These results could be responsible for lipid accumulation. The promoter methylation levels of pparγ were reduced and were the lowest in the 600 μg kg-1 group, and the promoter methylation levels of lcat were significantly increased in all the Phe treatments. These changes were matched with the alterations in their mRNA levels, suggesting that prenatal Phe exposure could induce abnormal lipid metabolism in later life via epigenetic modification.
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Affiliation(s)
- Jiaojiao Guo
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, PR China
| | - Shenli Zhang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, PR China
| | - Lu Fang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, PR China
| | - Jie Huang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, PR China
| | - Qian Wang
- College of Environment & Ecology, Xiamen University, Xiamen, PR China
| | - Chonggang Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, PR China.
| | - Meng Chen
- College of Environment & Ecology, Xiamen University, Xiamen, PR China.
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13
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Peinado FM, Artacho-Cordón F, Barrios-Rodríguez R, Arrebola JP. Influence of polychlorinated biphenyls and organochlorine pesticides on the inflammatory milieu. A systematic review of in vitro, in vivo and epidemiological studies. ENVIRONMENTAL RESEARCH 2020; 186:109561. [PMID: 32668538 DOI: 10.1016/j.envres.2020.109561] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 04/10/2020] [Accepted: 04/19/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) are relevant families of persistent organic pollutants, which have been linked to several long-term adverse health effects. The mechanisms of action of these pollutants are still poorly understood. However, there are some evidences suggesting that inflammation might play a key role on their effects. AIM To systematically synthesize the published in vitro, in vivo and epidemiological data assessing the potential influence of exposure to OCPs and PCBs on the development of an inflammatory milieu. METHODS A systematic review of peer-reviewed original research papers published until 1st May 2019 was conducted, by using Medline, Web of Science and Scopus databases. A total of 39 articles met the inclusion criteria and were evaluated in this review. RESULTS The majority of the studies showed significant associations of PCB and OCP exposure with all inflammatory markers measured (n = 30). Some studies showed positive and negative associations (n = 7) and only two studies evidenced negative associations (n = 2). Most of the available evidences came from in vitro and in vivo studies (n = 31), with few epidemiological studies (n = 8). CONCLUSIONS We found consistent positive associations between exposure to PCBs and OCPs and the development of a pro-inflammatory milieu, with only few discrepancies. However, given the limited epidemiological evidence found, our results warrant further research in order to elucidate the real contribution of these pollutants on the inflammatory processes and subsequent diseases.
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Affiliation(s)
- F M Peinado
- Instituto de Investigación Biosanitaria ibs.GRANADA, Granada, Spain
| | - F Artacho-Cordón
- Instituto de Investigación Biosanitaria ibs.GRANADA, Granada, Spain; University of Granada, Radiology and Physical Medicine Department, Granada, Spain; CIBER Epidemiology and Public Health (CIBERESP), Spain.
| | - R Barrios-Rodríguez
- Instituto de Investigación Biosanitaria ibs.GRANADA, Granada, Spain; University of Granada, Department of Preventive Medicine and Public Health, Granada, Spain; CIBER Epidemiology and Public Health (CIBERESP), Spain
| | - J P Arrebola
- Instituto de Investigación Biosanitaria ibs.GRANADA, Granada, Spain; University of Granada, Department of Preventive Medicine and Public Health, Granada, Spain; CIBER Epidemiology and Public Health (CIBERESP), Spain.
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14
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Jin J, Wahlang B, Shi H, Hardesty JE, Falkner KC, Head KZ, Srivastava S, Merchant ML, Rai SN, Cave MC, Prough RA. Dioxin-like and non-dioxin-like PCBs differentially regulate the hepatic proteome and modify diet-induced nonalcoholic fatty liver disease severity. Med Chem Res 2020; 29:1247-1263. [PMID: 32831531 PMCID: PMC7440142 DOI: 10.1007/s00044-020-02581-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 05/30/2020] [Indexed: 02/06/2023]
Abstract
Polychlorinated biphenyls (PCBs) are persistent organic pollutants associated with metabolic disruption and non-alcoholic fatty liver disease (NAFLD). Based on their ability to activate the aryl hydrocarbon receptor (AhR), PCBs are subdivided into two classes: dioxin-like (DL) and non-dioxin-like (NDL) PCBs. Previously, we demonstrated that NDL PCBs compromised the liver to promote more severe diet-induced NAFLD. Here, the hepatic effects and potential mechanisms (by untargeted liver proteomics) of DL PCBs, NDL PCBs or co-exposure to both in diet-induced NAFLD are investigated. Male C57Bl/6 mice were fed a 42% fat diet and exposed to vehicle control; Aroclor1260 (20 mg/kg, NDL PCB mixture); PCB126 (20 μg/kg, DL PCB congener); or a mixture of Aroclor1260 (20 mg/kg)+PCB126 (20 μg/kg) for 12 weeks. Each exposure was associated with a distinct hepatic proteome. Phenotypic and proteomic analyses revealed increased hepatic inflammation and phosphoprotein signaling disruption by Aroclor1260. PCB126 decreased hepatic inflammation and fibrosis at the molecular level; while altering cytoskeletal remodeling, metal homeostasis, and intermediary/xenobiotic metabolism. PCB126 attenuated Aroclor1260-induced hepatic inflammation but increased hepatic free fatty acids in the co-exposure group. Aroclor1260+PCB126 exposure was strongly associated with multiple epigenetic processes, and these could potentially explain the observed non-additive effects of the exposures on the hepatic proteome. Taken together, the results demonstrated that PCB exposures differentially regulated the hepatic proteome and the histologic severity of diet-induced NAFLD. Future research is warranted to determine the AhR-dependence of the observed effects including metal homeostasis and the epigenetic regulation of gene expression.
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Affiliation(s)
- Jian Jin
- Department of Pharmacology & Toxicology, School of Medicine, University of Louisville, Louisville, KY, 40202, USA
| | - Banrida Wahlang
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, 40202, USA
- UofL Superfund Research Center, University of Louisville, Louisville, KY, 40202, USA
| | - Hongxue Shi
- Department of Pharmacology & Toxicology, School of Medicine, University of Louisville, Louisville, KY, 40202, USA
- Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Josiah E. Hardesty
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, 40202, USA
| | - K. Cameron Falkner
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, 40202, USA
| | - Kimberly Z. Head
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, 40202, USA
| | - Sudhir Srivastava
- Department of Bioinformatics and Biostatistics, School of Public Health and Information Sciences, University of Louisville, Louisville, KY, 40202, USA
- Centre for Agricultural Bioinformatics, ICAR-Indian Agricultural Statistics Research Institute, New Delhi, 110012, India
| | - Michael L. Merchant
- UofL Superfund Research Center, University of Louisville, Louisville, KY, 40202, USA
- Division of Nephrology and Hypertension, School of Medicine, University of Louisville, Louisville, KY 40202, USA
| | - Shesh N. Rai
- UofL Superfund Research Center, University of Louisville, Louisville, KY, 40202, USA
- Department of Bioinformatics and Biostatistics, School of Public Health and Information Sciences, University of Louisville, Louisville, KY, 40202, USA
| | - Matthew C. Cave
- Department of Pharmacology & Toxicology, School of Medicine, University of Louisville, Louisville, KY, 40202, USA
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, 40202, USA
- UofL Superfund Research Center, University of Louisville, Louisville, KY, 40202, USA
- Department of Biochemistry & Molecular Genetics, School of Medicine, University of Louisville, Louisville, KY, 40202, USA
- Robley Rex Veterans Affairs Medical Center, Louisville, KY, 40206, USA
| | - Russell A. Prough
- Department of Biochemistry & Molecular Genetics, School of Medicine, University of Louisville, Louisville, KY, 40202, USA
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15
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Hoffman JB, Petriello MC, Morris AJ, Mottaleb MA, Sui Y, Zhou C, Deng P, Wang C, Hennig B. Prebiotic inulin consumption reduces dioxin-like PCB 126-mediated hepatotoxicity and gut dysbiosis in hyperlipidemic Ldlr deficient mice. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 261:114183. [PMID: 32105967 PMCID: PMC7220843 DOI: 10.1016/j.envpol.2020.114183] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 01/25/2020] [Accepted: 02/11/2020] [Indexed: 05/04/2023]
Abstract
Exposure to some environmental pollutants increases the risk of developing inflammatory disorders such as steatosis and cardiometabolic diseases. Diets high in fermentable fibers such as inulin can modulate the gut microbiota and lessen the severity of pro-inflammatory diseases, especially in individuals with elevated circulating cholesterol. Thus, we aimed to test the hypothesis that hyperlipidemic mice fed a diet enriched with 8% inulin would be protected from the pro-inflammatory toxic effects of PCB 126. Four groups of male Ldlr-/- mice were fed a high cholesterol diet containing 8% inulin or 8% cellulose (control) for 12 weeks. At weeks 2 and 4, mice were exposed to PCB 126 or vehicle (control). PCB 126 exposure induced wasting and impaired glucose tolerance, which were attenuated by inulin consumption. PCB 126 exposure induced hepatic lipid accumulation and increased inflammatory gene expression, which were both decreased by inulin consumption. In addition, inulin feeding decreased atherosclerotic lesion development in the aortic root and modulated the expression of enzymes related to glycolysis. Finally, 16S rRNA sequencing of gut microbial populations showed that PCB 126 modulated multiple microbiota genera (e.g., 3-fold decrease in Allobaculum and 3-fold increase in Coprococcus) which were normalized in inulin fed mice. Overall our data support the hypothesis that a dietary intervention that targets the gut microbiota may be an effective means of attenuating dioxin-like pollutant-mediated diseases.
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Affiliation(s)
- Jessie B Hoffman
- Superfund Research Center, University of Kentucky, Lexington, KY, USA; Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, USA
| | - Michael C Petriello
- Superfund Research Center, University of Kentucky, Lexington, KY, USA; Division of Cardiovascular Medicine, College of Medicine, University of Kentucky, Lexington, KY, USA; Lexington Veterans Affairs Medical Center, Lexington, KY, USA
| | - Andrew J Morris
- Superfund Research Center, University of Kentucky, Lexington, KY, USA; Division of Cardiovascular Medicine, College of Medicine, University of Kentucky, Lexington, KY, USA; Lexington Veterans Affairs Medical Center, Lexington, KY, USA
| | - M Abdul Mottaleb
- Superfund Research Center, University of Kentucky, Lexington, KY, USA; Division of Cardiovascular Medicine, College of Medicine, University of Kentucky, Lexington, KY, USA; Lexington Veterans Affairs Medical Center, Lexington, KY, USA
| | - Yipeng Sui
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, USA
| | - Changcheng Zhou
- Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, USA
| | - Pan Deng
- Superfund Research Center, University of Kentucky, Lexington, KY, USA; Department of Animal and Food Sciences, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, USA
| | - Chunyan Wang
- Superfund Research Center, University of Kentucky, Lexington, KY, USA; Department of Animal and Food Sciences, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, USA
| | - Bernhard Hennig
- Superfund Research Center, University of Kentucky, Lexington, KY, USA; Department of Animal and Food Sciences, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, USA.
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16
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Lagoa R, Marques-da-Silva D, Diniz M, Daglia M, Bishayee A. Molecular mechanisms linking environmental toxicants to cancer development: Significance for protective interventions with polyphenols. Semin Cancer Biol 2020; 80:118-144. [PMID: 32044471 DOI: 10.1016/j.semcancer.2020.02.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 01/25/2020] [Accepted: 02/01/2020] [Indexed: 12/12/2022]
Abstract
Human exposure to environmental toxicants with diverse mechanisms of action is a growing concern. In addition to well-recognized carcinogens, various chemicals in environmental and occupational settings have been suggested to impact health, increasing susceptibility to cancer by inducing genetic and epigenetic changes. Accordingly, in this review, we have discussed recent insights into the pathological mechanisms of these chemicals, namely their effects on cell redox and calcium homeostasis, mitochondria and inflammatory signaling, with a focus on the possible implications for multi-stage carcinogenesis and its reversal by polyphenols. Plant-derived polyphenols, such as epigallocatechin-gallate, resveratrol, curcumin and anthocyanins reduce the incidence of cancer and can be useful nutraceuticals for alleviating the detrimental outcomes of harmful pollutants. However, development of therapies based on polyphenol administration requires further studies to validate the biological efficacy, identifying effective doses, mode of action and new delivery forms. Innovative microphysiological testing models are presented and specific proposals for future trials are given. Merging the current knowledge of multifactorial actions of specific polyphenols and chief environmental toxicants, this work aims to potentiate the delivery of phytochemical-based protective treatments to individuals at high-risk due to environmental exposure.
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Affiliation(s)
- Ricardo Lagoa
- School of Technology and Management, Polytechnic Institute of Leiria, Morro do Lena, Alto do Vieiro, 2411-901 Leiria, Portugal; Applied Molecular Biosciences Unit, NOVA School of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal.
| | - Dorinda Marques-da-Silva
- School of Technology and Management, Polytechnic Institute of Leiria, Morro do Lena, Alto do Vieiro, 2411-901 Leiria, Portugal; Applied Molecular Biosciences Unit, NOVA School of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal
| | - Mário Diniz
- Applied Molecular Biosciences Unit, NOVA School of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal; Department of Chemistry, NOVA School of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal
| | - Maria Daglia
- Department of Pharmacy, University of Naples Federico II, 80131 Naples, Italy; International Research Center for Food Nutrition and Safety, Jiangsu University, Zhenjiang 212013, China
| | - Anupam Bishayee
- Lake Erie College of Osteopathic Medicine, 5000 Lakewood Ranch Boulevard, Bradenton, FL 34211, USA
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Ruan J, Guo J, Huang Y, Mao Y, Yang Z, Zuo Z. Adolescent exposure to environmental level of PCBs (Aroclor 1254) induces non-alcoholic fatty liver disease in male mice. ENVIRONMENTAL RESEARCH 2020; 181:108909. [PMID: 31776016 DOI: 10.1016/j.envres.2019.108909] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 11/06/2019] [Accepted: 11/07/2019] [Indexed: 06/10/2023]
Abstract
Polychlorinated biphenyls (PCBs) are persistent organic pollutants found in various environmental media, and there is growing evidence that PCBs may contribute to the pathogenesis of non-alcoholic fatty liver disease (NAFLD). The purposes of this study were to investigate whether environmental level of Aroclor 1254 (a commercial mixture of PCBs) exposure to adolescent male mice could induce the development of NAFLD and the mechanisms involved. Twenty-one-day-old male C57BL/6 mice were exposed to Aroclor 1254 (0.5-500 μg/kg body weight) by oral gavage once every third day for 60 days. The results showed that exposure to Aroclor 1254 increased body weight and decreased the liver-somatic index in a dose-dependent manner. Aroclor 1254 administration increased lipid accumulation in the liver and induced the mRNA expression of genes associated with lipogenesis, including acetyl-CoA carboxylase 1 (Acc1), acetyl-CoA carboxylase 2 (Acc2) and fatty acid synthase (Fasn). Moreover, Aroclor 1254 decreased peroxisome proliferator-activated receptor alpha (PPARα) signaling and lipid oxidation. In addition, we found that Aroclor 1254 administration induced oxidative stress in mouse liver and elevated the protein level of cyclooxygenase 2 (COX-2), an inflammatory molecule, possibly via the endoplasmic reticulum (ER) stress inositol-requiring enzyme 1α-X-box-binding protein-1 (IRE1α-XBP1) pathway, but not the nuclear factor-κB (NF-κB) pathway. In summary, adolescent exposure to environmental level of PCBs stimulated oxidative stress, ER stress and the inflammatory response and caused NAFLD in male mice. This work provides new insight into the idea that adolescent exposure to environmental level of PCBs might induce the development of NAFLD under the regulation of ER stress in males.
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Affiliation(s)
- Jinpeng Ruan
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, 361005, China
| | - Jiaojiao Guo
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, 361005, China
| | - Yameng Huang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, 361005, China
| | - Yunzi Mao
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, 361005, China
| | - Zhenggang Yang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, 361005, China
| | - Zhenghong Zuo
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, 361005, China.
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18
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Shan Q, Li H, Chen N, Qu F, Guo J. Understanding the Multiple Effects of PCBs on Lipid Metabolism. Diabetes Metab Syndr Obes 2020; 13:3691-3702. [PMID: 33116719 PMCID: PMC7568599 DOI: 10.2147/dmso.s264851] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 08/19/2020] [Indexed: 12/28/2022] Open
Abstract
Polychlorinated biphenyls (PCBs) are a typical class of environmental contaminants recently shown to be metabolism-disrupting chemicals. Lipids are a highly complex group of biomolecules that not only form the structural basis of biofilms but also act as signaling molecules and energy sources. Lipid metabolic disorders contribute to multiple diseases, including obesity, diabetes, fatty liver, and metabolic syndromes. Although previous literature has reported that PCBs can affect lipid metabolism, including lipid synthesis, uptake, and elimination, few systematic summaries of the detailed process of lipid metabolism caused by PCB exposure have been published. Lipid metabolic processes involve many molecules; however, the key factors that are sensitive to PCB exposure have not been fully clarified. Here, we summarize the recent developments in PCB research with a focus on biomarkers of lipid metabolic disorders related to environmental exposures.
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Affiliation(s)
- Qiuli Shan
- College of Biological Science and Technology, University of Jinan, Jinan250022, People’s Republic of China
- State Key Laboratory of Environmental Chemistry and Eco-Toxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing100085, People’s Republic of China
- Correspondence: Qiuli Shan Email
| | - Hongmei Li
- College of Biological Science and Technology, University of Jinan, Jinan250022, People’s Republic of China
| | - Ningning Chen
- College of Biological Science and Technology, University of Jinan, Jinan250022, People’s Republic of China
| | - Fan Qu
- College of Biological Science and Technology, University of Jinan, Jinan250022, People’s Republic of China
| | - Jing Guo
- College of Biological Science and Technology, University of Jinan, Jinan250022, People’s Republic of China
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19
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Leblanc AF, Attignon EA, Distel E, Karakitsios SP, Sarigiannis DA, Bortoli S, Barouki R, Coumoul X, Aggerbeck M, Blanc EB. A dual mixture of persistent organic pollutants modifies carbohydrate metabolism in the human hepatic cell line HepaRG. ENVIRONMENTAL RESEARCH 2019; 178:108628. [PMID: 31520823 DOI: 10.1016/j.envres.2019.108628] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 07/12/2019] [Accepted: 08/04/2019] [Indexed: 06/10/2023]
Abstract
Individuals as well as entire ecosystems are exposed to mixtures of Persistent Organic Pollutants (POPs). Previously, we showed, by a non-targeted approach, that the expression of several genes involved in carbohydrate metabolism was almost completely inhibited in the human hepatic cell line HepaRG following exposure to a mixture of the organochlorine insecticide alpha-endosulfan and 2,3,7,8 tetrachlorodibenzo-p-dioxin. In this European HEALS project, which studies the effects of the exposome on human health, we used a Physiologically Based BioKinetic model to compare the concentrations previously used in vitro with in vivo exposures for humans. We investigated the effects of these POPs on the levels of proteins, on glycogen content, glucose production and the oxidation of glucose into CO2 and correlated them to the expression of genes involved in carbohydrate metabolism as measured by RT-qPCR. Exposure to individual POPs and the mixture decreased the expression of the proteins investigated as well as glucose output (up to 82%), glucose oxidation (up to 29%) and glycogen content (up to 48%). siRNAs that specifically inhibit the expression of several xenobiotic receptors were used to assess receptor involvement in the effects of the POPs. In the HepaRG model, we demonstrate that the effects are mediated by the aryl hydrocarbon receptor and the estrogen receptor alpha, but not the pregnane X receptor or the constitutive androstane receptor. These results provide evidence that exposure to combinations of POPs, acting through different signaling pathways, may affect, more profoundly than single pollutants alone, metabolic pathways such as carbohydrate/energy metabolism and play a potential role in pollutant associated metabolic disorders.
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Affiliation(s)
- Alix F Leblanc
- INSERM UMR-S 1124, Toxicité Environnementale, Cibles Thérapeutiques, Signalisation Cellulaire et Biomarqueurs, 45 rue des Saints Pères, 75006, Paris, France; Université de Paris, Université Paris Descartes, 45 rue des Saints Pères, 75006, Paris, France.
| | - Eléonore A Attignon
- INSERM UMR-S 1124, Toxicité Environnementale, Cibles Thérapeutiques, Signalisation Cellulaire et Biomarqueurs, 45 rue des Saints Pères, 75006, Paris, France; Université de Paris, Université Paris Descartes, 45 rue des Saints Pères, 75006, Paris, France.
| | - Emilie Distel
- INSERM UMR-S 1124, Toxicité Environnementale, Cibles Thérapeutiques, Signalisation Cellulaire et Biomarqueurs, 45 rue des Saints Pères, 75006, Paris, France; Université de Paris, Université Paris Descartes, 45 rue des Saints Pères, 75006, Paris, France.
| | - Spyros P Karakitsios
- Aristotle University of Thessaloniki, Department of Chemical Engineering, 54 124, Thessaloniki, Greece.
| | - Dimosthenis A Sarigiannis
- Aristotle University of Thessaloniki, Department of Chemical Engineering, 54 124, Thessaloniki, Greece; Environmental Health Engineering, Institute for Advanced Study, Pavia, Italy.
| | - Sylvie Bortoli
- INSERM UMR-S 1124, Toxicité Environnementale, Cibles Thérapeutiques, Signalisation Cellulaire et Biomarqueurs, 45 rue des Saints Pères, 75006, Paris, France; Université de Paris, Université Paris Descartes, 45 rue des Saints Pères, 75006, Paris, France.
| | - Robert Barouki
- INSERM UMR-S 1124, Toxicité Environnementale, Cibles Thérapeutiques, Signalisation Cellulaire et Biomarqueurs, 45 rue des Saints Pères, 75006, Paris, France; Université de Paris, Université Paris Descartes, 45 rue des Saints Pères, 75006, Paris, France; AP-HP, Hôpital Necker-Enfants Malades, Service de Biochimie Métabolique, 149, rue de Sèvres, 75743, Paris, France.
| | - Xavier Coumoul
- INSERM UMR-S 1124, Toxicité Environnementale, Cibles Thérapeutiques, Signalisation Cellulaire et Biomarqueurs, 45 rue des Saints Pères, 75006, Paris, France; Université de Paris, Université Paris Descartes, 45 rue des Saints Pères, 75006, Paris, France.
| | - Martine Aggerbeck
- INSERM UMR-S 1124, Toxicité Environnementale, Cibles Thérapeutiques, Signalisation Cellulaire et Biomarqueurs, 45 rue des Saints Pères, 75006, Paris, France; Université de Paris, Université Paris Descartes, 45 rue des Saints Pères, 75006, Paris, France.
| | - Etienne B Blanc
- INSERM UMR-S 1124, Toxicité Environnementale, Cibles Thérapeutiques, Signalisation Cellulaire et Biomarqueurs, 45 rue des Saints Pères, 75006, Paris, France; Université de Paris, Université Paris Descartes, 45 rue des Saints Pères, 75006, Paris, France.
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20
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Wahlang B, Jin J, Beier JI, Hardesty JE, Daly EF, Schnegelberger RD, Falkner KC, Prough RA, Kirpich IA, Cave MC. Mechanisms of Environmental Contributions to Fatty Liver Disease. Curr Environ Health Rep 2019; 6:80-94. [PMID: 31134516 PMCID: PMC6698418 DOI: 10.1007/s40572-019-00232-w] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE Fatty liver disease (FLD) affects over 25% of the global population and may lead to liver-related mortality due to cirrhosis and liver cancer. FLD caused by occupational and environmental chemical exposures is termed "toxicant-associated steatohepatitis" (TASH). The current review addresses the scientific progress made in the mechanistic understanding of TASH since its initial description in 2010. RECENT FINDINGS Recently discovered modes of actions for volatile organic compounds and persistent organic pollutants include the following: (i) the endocrine-, metabolism-, and signaling-disrupting chemical hypotheses; (ii) chemical-nutrient interactions and the "two-hit" hypothesis. These key hypotheses were then reviewed in the context of the steatosis adverse outcome pathway (AOP) proposed by the US Environmental Protection Agency. The conceptual understanding of the contribution of environmental exposures to FLD has progressed significantly. However, because this is a new research area, more studies including mechanistic human data are required to address current knowledge gaps.
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Affiliation(s)
- Banrida Wahlang
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Louisville School of Medicine, Louisville, KY, 40202, USA
- University of Louisville Superfund Research Center, University of Louisville, Louisville, KY, 40202, USA
| | - Jian Jin
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Juliane I Beier
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh, Pittsburgh, PA, 15213, USA
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Josiah E Hardesty
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Erica F Daly
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Regina D Schnegelberger
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - K Cameron Falkner
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Russell A Prough
- Department of Biochemistry and Molecular Genetics, University of Louisville School of Medicine, Louisville, KY, 40202, USA
| | - Irina A Kirpich
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Louisville School of Medicine, Louisville, KY, 40202, USA
- Hepatobiology & Toxicology COBRE Center, University of Louisville School of Medicine, Louisville, KY, 40202, USA
- University of Louisville Alcohol Research Center, University of Louisville, Louisville, KY, 40202, USA
| | - Matthew C Cave
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Louisville School of Medicine, Louisville, KY, 40202, USA.
- University of Louisville Superfund Research Center, University of Louisville, Louisville, KY, 40202, USA.
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY, 40202, USA.
- Department of Biochemistry and Molecular Genetics, University of Louisville School of Medicine, Louisville, KY, 40202, USA.
- Hepatobiology & Toxicology COBRE Center, University of Louisville School of Medicine, Louisville, KY, 40202, USA.
- University of Louisville Alcohol Research Center, University of Louisville, Louisville, KY, 40202, USA.
- The Robley Rex Veterans Affairs Medical Center, Louisville, KY, 40206, USA.
- The Jewish Hospital Liver Transplant Program, Louisville, KY, 40202, USA.
- Kosair Charities Clinical & Translational Research Building, 505 South Hancock Street, Louisville, KY, 40202, USA.
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Abstract
Polychlorinated biphenyls (PCBs) have been associated with abnormal liver enzymes and suspected nonalcoholic fatty liver disease (NAFLD) in cohort studies. NAFLD affects greater than 25% of the global population and may result in liver-related mortality. Both dioxin-like and non-dioxin-like PCBs have been associated with NAFLD, but their effects and mechanisms differ. Dioxin-like PCBs altered the gut:liver axis and microbiome and caused hepatic steatosis by disrupting hepatic lipid metabolism. In contrast, NDL PCBs reduced the liver's protective responses to promote diet-induced NAFLD. Mechanisms included the disruption of phosphoprotein signaling resulting in altered nuclear receptor function.
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22
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Shen X, Chen Y, Zhang J, Yan X, Liu W, Guo Y, Shan Q, Liu S. Low-dose PCB126 compromises circadian rhythms associated with disordered glucose and lipid metabolism in mice. ENVIRONMENT INTERNATIONAL 2019; 128:146-157. [PMID: 31055201 DOI: 10.1016/j.envint.2019.04.058] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/25/2019] [Accepted: 04/25/2019] [Indexed: 06/09/2023]
Abstract
It has been documented that 3, 3', 4, 4', 5-pentachlorobiphenyl (PCB126) elicits diverse detrimental effects on human health including metabolic syndrome and non-alcoholic fatty-liver disease (NAFLD), through a wide array of non-carcinogenic mechanisms, which require further detailed investigations. The circadian clock system consists of central clock machinery (located in the suprachiasmatic nucleus in the hypothalamus) and the peripheral clocks (located in nearly all peripheral tissues). Peripheral clocks in the liver play fundamental roles in maintaining liver homeostasis, including the regulation of energy metabolism and the expression of enzymes that fine-tune the absorption and metabolism of xenobiotics. However, the molecular basis of whether PCB126 disrupts liver homeostasis (e.g., glucose and lipid metabolism) by dysregulating the circadian clock system is still unknown. Thus, we performed a set of comprehensive analyses of glucose and lipid metabolism in the liver tissues from low-dose PCB126-treated mice. Our results demonstrated that PCB126 diminished glucose and cholesterol levels in serum and elevated glucose and cholesterol levels in the liver. Moreover, PCB126 compromised PGC1α and PDHE1α, which are the driving force for mitochondrial biogenesis and entry of pyruvate into the tricarboxylic acid (TCA) cycle, respectively, and resulted in the accumulation of glucose, glycogen and pyruvate in the liver after PCB126 exposure. Additionally, PCB126 blocked hepatic cholesterol metabolism and export pathways, leading to an elevated localization of hepatic cholesterol. Mechanistic investigations illustrated that PCB126 greatly altered the expression profile of core clock genes and their target rhythm genes involved in orchestrating glucose and cholesterol metabolism. Together, our results demonstrated that a close correlation between PCB126-disturbed glucose and lipid metabolism and disordered physiological oscillation of circadian genes.
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Affiliation(s)
- Xinming Shen
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing, China
| | - Yongjiu Chen
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing, China
| | - Jie Zhang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing, China
| | - Xu Yan
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing, China
| | - Wei Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing, China
| | - Yifan Guo
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Qiuli Shan
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Sijin Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing, China.
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23
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Wahlang B, Jin J, Hardesty JE, Head KZ, Shi H, Falkner KC, Prough RA, Klinge CM, Cave MC. Identifying sex differences arising from polychlorinated biphenyl exposures in toxicant-associated liver disease. Food Chem Toxicol 2019; 129:64-76. [PMID: 31026535 DOI: 10.1016/j.fct.2019.04.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 03/24/2019] [Accepted: 04/06/2019] [Indexed: 12/14/2022]
Abstract
Exposures to persistent environmental pollutants like polychlorinated biphenyls (PCBs) has been associated with liver diseases such as toxicant-associated steatohepatitis (TASH). However, previously published PCB hepatotoxicity studies evaluated mostly male animal models. Moreover, epidemiologic studies on PCB-exposed cohorts evaluating sex differences are scarce. Therefore, the objective of this study was to examine hepato-toxicological responses of PCB exposures in the context of sex-dependent outcomes. Male and female C57Bl/6 mice were exposed to Aroclor 1260 (20 mg/kg), and PCB126 (20 μg/kg), by gavage for two weeks. Female mice appeared to be more sensitive to PCB-induced hepatotoxic effects as manifested by increased liver injury markers, namely, hepatic Serpine1 expression. Additionally, compared to their male counterparts, PCB-exposed females exhibited dysregulated hepatic gene expression favoring lipid accumulation rather than lipid breakdown; accompanied by dyslipidemia. Sex differences were also observed in the expression and activation of PCB targets such as the epidermal growth factor receptor (EGFR) while PCB-induced pancreatic toxicity was similar in both sexes. Importantly, PCB exposure appeared to cause pro-androgenic, anti-estrogenic along with sex-dependent thyroid hormone effects. The overall findings demonstrated that the observed PCB-mediated hepatotoxicity was sex-dependent; confirming the existence of sex differences in environmental exposure-induced markers of TASH and warrants further investigation.
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Affiliation(s)
- Banrida Wahlang
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, USA; UofL Superfund Research Center, University of Louisville, Louisville, KY, USA
| | - Jian Jin
- Department of Pharmacology & Toxicology, School of Medicine, University of Louisville, Louisville, KY, USA
| | - Josiah E Hardesty
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, USA
| | - Kimberly Z Head
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, USA
| | - Hongxue Shi
- Department of Cell & Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - K Cameron Falkner
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, USA
| | - Russell A Prough
- Department of Biochemistry & Molecular Genetics, School of Medicine, University of Louisville, Louisville, KY, USA
| | - Carolyn M Klinge
- Department of Biochemistry & Molecular Genetics, School of Medicine, University of Louisville, Louisville, KY, USA
| | - Matthew C Cave
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, USA; UofL Superfund Research Center, University of Louisville, Louisville, KY, USA; Department of Pharmacology & Toxicology, School of Medicine, University of Louisville, Louisville, KY, USA; Department of Biochemistry & Molecular Genetics, School of Medicine, University of Louisville, Louisville, KY, USA; Robley Rex Veterans Affairs Medical Center, Louisville, KY, USA.
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24
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Shi H, Hardesty JE, Jin J, Head KZ, Falkner KC, Cave MC, Prough RA. Concentration dependence of human and mouse aryl hydrocarbon receptor responsiveness to polychlorinated biphenyl exposures: Implications for aroclor mixtures. Xenobiotica 2019; 49:1414-1422. [PMID: 30991879 DOI: 10.1080/00498254.2019.1566582] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
1. Aryl hydrocarbon receptor (AhR) ligands, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs), are endocrine disrupting chemicals associated with nonalcoholic fatty liver disease. This study documents the species-specific differences between mouse (high affinity mAhR) and human AhR (hAhR) activation by PCB congeners and Aroclor mixtures. 2. AhR activation by TCDD or PCBs 77, 81, 114, 114, 126, and 169 was measured using luciferase reporter constructs transfected into either Hepa1c1c7 mouse or HepG2 human liver cell lines. The EC50 values were lower in Hepa1c1c7 cells than HepG2 cells for all compounds tested except PCB 81. The results for TCDD and PCB 126 were validated in primary human and mouse hepatocytes by measuring CYP1A1 gene transcript levels. 3. Because humans are exposed to PCB mixtures, several mixtures (Aroclors 1254; 1260; and 1260 + 0.1% PCB126 each at 10 µg/ml) were then tested. Neither Aroclor 1254 nor Aroclor 1260 increased luciferase activity by the transfected AhR reporter construct. The Aroclor 1260 + 0.1% PCB 126 mixture induced mAhR-mediated transactivation, but not hAhR activation in cell lines. 4. In summary, significant concentration-dependent differences exist between human and mouse AhR activation by PCBs. Relative effect potencies differed, in some cases, from published toxic equivalency factors.
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Affiliation(s)
- Hongxue Shi
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University , Chicago , IL , USA
| | - Josiah E Hardesty
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Louisville School of Medicine , Louisville , KY , USA
| | - Jian Jin
- Department of Pharmacology & Toxicology, University of Louisville School of Medicine , Louisville , KY , USA
| | - Kimberly Z Head
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Louisville School of Medicine , Louisville , KY , USA
| | - K Cameron Falkner
- Department of Medicine, Division of Gastroenterology, University of Louisville School of Medicine , Louisville , KY , USA
| | - Matthew C Cave
- Department of Medicine, Division of Gastroenterology, University of Louisville School of Medicine , Louisville , KY , USA
| | - Russell Allen Prough
- Department of Biochemistry & Molecular Genetics, University of Louisville School of Medicine , Louisville , KY , USA
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25
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Wu JP, Peng Y, Zhi H, Chen XY, Wu SK, Tao L, Zeng YH, Luo XJ, Mai BX. Contamination of organohalogen chemicals and hepatic steatosis in common kingfisher (Alcedo atthis) breeding at a nature reserve near e-waste recycling sites in South China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 659:561-567. [PMID: 31096385 DOI: 10.1016/j.scitotenv.2018.12.395] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 12/25/2018] [Accepted: 12/25/2018] [Indexed: 06/09/2023]
Abstract
Severe pollution of organohalogen compounds (OHCs) including PBDEs, PCBs and DDTs is demonstrated in e-waste recycling sites and metropolis in South China, but relatively little is known of their impacts on wildlife that inhabits nature reserves in this region, especially those located at the neighborhood areas of e-waste recycling sites. In the present study, PBDEs, PCBs and DDTs as well as liver histological changes were examined in common kingfisher breeding at a nature reserve (Shimentai National Nature Reserve, SNNR) near a notorious e-waste recycling site in South China. Mean ∑PBDEs (84.9 ng/g lipid weight), ∑PCBs (397 ng/g) and ∑TEQs (total toxic equivalent of coplanar PCBs, 2.68 ng/g) concentrations in kingfishers from SNNR were approximately 2-, 5-, and 4-fold higher than those detected in a reference population, respectively; suggesting contamination of the e-waste-derived OHCs in SNNR. Mean ∑DDTs concentration (2150 ng/g) in kingfishers from SNNR was also higher (~2-fold) than that from the reference samples. While ∑DDTs dominated the composition of the OHCs at both sampling sites, ∑PCBs was also important in kingfishers from SNNR, averaging 15% of ∑OHCs. Histological examination of the liver showed steatosis occurred in 60% of the kingfishers from SNNR. Birds with hepatic steatosis had significantly (p = 0.03) higher ∑TEQs than those without steatosis. Similar trends were also found for ∑PCBs and ∑DDTs, although it is not statistically significant. It therefore seems likely that the hepatic steatosis were associated with the relatively high body-burden of OHCs, although the possibility of other factors resulting in hepatic steatosis cannot be ruled out.
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Affiliation(s)
- Jiang-Ping Wu
- Anhui Provincial Engineering Laboratory of Water and Soil Pollution Control and Remediation, College of Environmental Science and Engineering, Anhui Normal University, Wuhu 241002, China
| | - Ying Peng
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China; State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Hui Zhi
- School of Basic Medical Sciences, Wannan Medical College, Wuhu 241002, China
| | - Xiao-Yun Chen
- Anhui Provincial Engineering Laboratory of Water and Soil Pollution Control and Remediation, College of Environmental Science and Engineering, Anhui Normal University, Wuhu 241002, China
| | - Si-Kang Wu
- Anhui Provincial Engineering Laboratory of Water and Soil Pollution Control and Remediation, College of Environmental Science and Engineering, Anhui Normal University, Wuhu 241002, China
| | - Lin Tao
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Yan-Hong Zeng
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xiao-Jun Luo
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Bi-Xian Mai
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
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Hardesty JE, Wahlang B, Falkner KC, Shi H, Jin J, Zhou Y, Wilkey DW, Merchant ML, Watson CT, Feng W, Morris AJ, Hennig B, Prough RA, Cave MC. Proteomic Analysis Reveals Novel Mechanisms by Which Polychlorinated Biphenyls Compromise the Liver Promoting Diet-Induced Steatohepatitis. J Proteome Res 2019; 18:1582-1594. [PMID: 30807179 DOI: 10.1021/acs.jproteome.8b00886] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Environmental pollution contributes to fatty liver disease pathogenesis. Polychlorinated biphenyl (PCB) exposures have been associated with liver enzyme elevation and suspected steatohepatitis in cohort studies. Male mice treated with the commercial PCB mixture, Aroclor 1260 (20 mg/kg), and fed high fat diet (HFD) for 12 weeks developed steatohepatitis. Receptor-based modes of action including inhibition of the epidermal growth factor (EGF) receptor were previously proposed, but other mechanisms likely exist. Objectives were to identify and validate the pathways, transcription factors, and mechanisms responsible for the steatohepatitis associated with PCB and HFD coexposures. Comparative proteomics analysis was performed in archived mouse liver samples from the aforementioned chronic exposure study. Pathway and transcription factor analysis (TFA) was performed, and selected results were validated. Liver proteomics detected 1103 unique proteins. Aroclor 1260 upregulated 154 and downregulated 93 of these. Aroclor 1260 + HFD coexposures affected 55 pathways including glutathione metabolism, intermediary metabolism, and cytoskeletal remodeling. TFA of Aroclor 1260 treatment demonstrated alterations in the function of 42 transcription factors including downregulation of NRF2 and key nuclear receptors previously demonstrated to protect against steatohepatitis (e.g., HNF4α, FXR, PPARα/δ/γ, etc.). Validation studies demonstrated that Aroclor 1260 significantly reduced HNF4α protein levels, while Aroclor 1260 + HFD reduced expression of the HNF4α target gene, albumin, in vivo. Aroclor 1260 attenuated EGF-dependent HNF4α phosphorylation and target gene activation in vitro. Aroclor 1260 reduced levels of NRF2, its target genes, and glutathione in vivo. Aroclor 1260 attenuated EGF-dependent NRF2 upregulation, in vitro. Aroclor 1260 indirectly activated hepatic stellate cells in vitro via induction of hepatocyte-derived TGFβ. PCB exposures adversely impacted transcription factors regulating liver protection, function, and fibrosis. PCBs, thus, compromised the liver by reducing its protective responses against nutritional stress to promote diet-induced steatohepatitis. The identified mechanisms by which environmental pollutants influence fatty liver disease pathogenesis require confirmation in humans.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Andrew J Morris
- Superfund Research Center , University of Kentucky , Lexington , Kentucky 40536 , United States
| | - Bernhard Hennig
- Superfund Research Center , University of Kentucky , Lexington , Kentucky 40536 , United States
| | | | - Matthew C Cave
- The Robley Rex Veterans Affairs Medical Center , Louisville , Kentucky 40206 , United States.,The Jewish Hospital Liver Transplant Program , Louisville , Kentucky 40202 , United States
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27
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Petriello MC, Brandon JA, Hoffman J, Wang C, Tripathi H, Abdel-Latif A, Ye X, Li X, Yang L, Lee E, Soman S, Barney J, Wahlang B, Hennig B, Morris AJ. Dioxin-like PCB 126 Increases Systemic Inflammation and Accelerates Atherosclerosis in Lean LDL Receptor-Deficient Mice. Toxicol Sci 2019; 162:548-558. [PMID: 29216392 DOI: 10.1093/toxsci/kfx275] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Exposure to dioxins and related persistent organic pollutants likely contributes to cardiovascular disease (CVD) risk through multiple mechanisms including the induction of chronic inflammation. Epidemiological studies have shown that leaner individuals may be more susceptible to the detrimental effects of lipophilic toxicants because they lack large adipose tissue depots that can accumulate and sequester these pollutants. This phenomenon complicates efforts to study mechanisms of pollutant-accelerated atherosclerosis in experimental animal models where high-fat feeding and adipose expansion limit the bioavailability of lipophilic pollutants. Here, we investigated whether a model dioxin-like pollutant, PCB 126, could increase inflammation and accelerate atherosclerosis in Ldlr-/- mice fed a low-fat atherogenic diet. We fed Ldlr-/- mice the Clinton/Cybulsky diet (10% kcal fat, 0.15% cholesterol) and sacrificed mice at 8, 10, or 12 weeks postPCB (2 doses of 1 μmol/kg) or vehicle gavage. To characterize this novel model, we examined the effects of PCB 126 on markers of systemic inflammation, hematological indices, fatty livers, and atherosclerotic lesion size. Mice exposed to PCB 126 exhibited significantly increased plasma inflammatory cytokine levels, increased circulating biomarkers of CVD, altered platelet, and red blood cell counts, increased accumulation of hepatic fatty acids, and accelerated atherosclerotic lesion formation in the aortic root. PCB 126 also increased circulating neutrophils, monocytes, and macrophages as determined by flow cytometry analysis. Exposure to dioxin-like PCB 126 increases inflammation and accelerates atherosclerosis in mice. This low-fat atherogenic diet may provide a useful tool to study the mechanisms linking exposure to lipophilic pollutants to increased risk of CVD.
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Affiliation(s)
- Michael C Petriello
- Division of Cardiovascular Medicine, College of Medicine.,Superfund Research Center, University of Kentucky, Lexington, Kentucky 40536.,Lexington Veterans Affairs Medical Center, Lexington, Kentucky 40502
| | | | - Jessie Hoffman
- Superfund Research Center, University of Kentucky, Lexington, Kentucky 40536.,Department of Pharmacology and Nutritional Sciences, College of Medicine
| | - Chunyan Wang
- Superfund Research Center, University of Kentucky, Lexington, Kentucky 40536.,Department of Animal and Food Sciences, College of Agriculture Food and Environment
| | - Himi Tripathi
- Gill Heart and Vascular Institute and Division of Cardiovascular Medicine
| | - Ahmed Abdel-Latif
- Gill Heart and Vascular Institute and Division of Cardiovascular Medicine
| | - Xiang Ye
- Department of Physiology, Saha Cardiovascular Research Center
| | - Xiangan Li
- Department of Physiology, Saha Cardiovascular Research Center
| | - Liping Yang
- Division of Cardiovascular Medicine, College of Medicine
| | - Eun Lee
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Kentucky, Lexington, Kentucky 40536
| | - Sony Soman
- Division of Cardiovascular Medicine, College of Medicine.,Superfund Research Center, University of Kentucky, Lexington, Kentucky 40536.,Lexington Veterans Affairs Medical Center, Lexington, Kentucky 40502
| | - Jazmyne Barney
- Superfund Research Center, University of Kentucky, Lexington, Kentucky 40536
| | - Banrida Wahlang
- Superfund Research Center, University of Kentucky, Lexington, Kentucky 40536
| | - Bernhard Hennig
- Superfund Research Center, University of Kentucky, Lexington, Kentucky 40536.,Department of Animal and Food Sciences, College of Agriculture Food and Environment
| | - Andrew J Morris
- Division of Cardiovascular Medicine, College of Medicine.,Superfund Research Center, University of Kentucky, Lexington, Kentucky 40536.,Lexington Veterans Affairs Medical Center, Lexington, Kentucky 40502
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28
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Hardesty JE, Wahlang B, Falkner KC, Shi H, Jin J, Wilkey D, Merchant M, Watson C, Prough RA, Cave MC. Hepatic signalling disruption by pollutant Polychlorinated biphenyls in steatohepatitis. Cell Signal 2019; 53:132-139. [PMID: 30300668 PMCID: PMC6289731 DOI: 10.1016/j.cellsig.2018.10.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 10/04/2018] [Accepted: 10/05/2018] [Indexed: 12/23/2022]
Abstract
BACKGROUND Polychlorinated biphenyl-mediated steatohepatitis has been shown to be due in part to inhibition of epidermal growth factor receptor (EGFR) signalling. EGFR signalling regulates many facets of hepatocyte function, but it is unclear which other kinases and pathways are involved in the development of toxicant-associated steatohepatitis (TASH). METHODS Comparative hepatic phosphoproteomic analysis was used to identify which kinases were affected by either PCB exposure (Aroclor 1260 mixture), high fat diet (HFD), or their interaction in a chronic exposure model of TASH. Cellular assays and western blot analysis were used to validate the phosphoproteomic findings. RESULTS 1760 unique phosphorylated peptides were identified and of those 588 were significantly different. PCB exposure and dietary interaction promoted a near 25% reduction of hepatic phospho-peptides. Leptin and insulin signalling were pathways highly affected by PCB exposure and liver necrosis was a pathologic ontology over represented due to interaction between PCBs and a HFD. Casein kinase 2 (CK2), Extracellular regulated kinase (ERK), Protein kinase B (AKT), and Cyclin dependent kinase (CDK) activity were demonstrated to be downregulated after PCB exposure and this downregulation was exacerbated with a HFD. PCB exposure led to a loss of hepatic CK2 subunit expression limiting CK2 kinase activity and negatively regulating caspase-3 (CASP3). PCBs promoted secondary necrosis in vitro validating the latter observation. The loss of hepatic phosphoprotein signalling appeared to be due to decreased signal transduction rather than phosphatase upregulation. CONCLUSIONS PCBs are signal disrupting chemicals that promote secondary necrosis through affecting a myriad of liver processes including metabolism and cellular maintenance. PCB exposure, particularly with interaction with a HFD greatly down-regulates the hepatic kinome. More data are needed on signalling disruption and its impact on liver health.
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Affiliation(s)
- Josiah E Hardesty
- Department of Biochemistry and Molecular Genetics, University of Louisville School of Medicine, Louisville, KY 40202, USA.
| | - Banrida Wahlang
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Louisville School of Medicine, Louisville, KY 40202, USA; University of Louisville Superfund Research Program, University of Louisville, Louisville, KY 40202, USA.
| | - K Cameron Falkner
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Louisville School of Medicine, Louisville, KY 40202, USA; Hepatobiology & Toxicology Center, University of Louisville School of Medicine, Louisville, KY 40202, USA.
| | - Hongxue Shi
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40202, USA.
| | - Jian Jin
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40202, USA.
| | - Daniel Wilkey
- The Proteomics Core, University of Louisville School of Medicine, Louisville, KY 40202, USA.
| | - Michael Merchant
- The Proteomics Core, University of Louisville School of Medicine, Louisville, KY 40202, USA.
| | - Corey Watson
- Department of Biochemistry and Molecular Genetics, University of Louisville School of Medicine, Louisville, KY 40202, USA.
| | - Russell A Prough
- Department of Biochemistry and Molecular Genetics, University of Louisville School of Medicine, Louisville, KY 40202, USA.
| | - Matthew C Cave
- Department of Biochemistry and Molecular Genetics, University of Louisville School of Medicine, Louisville, KY 40202, USA; Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40202, USA; Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Louisville School of Medicine, Louisville, KY 40202, USA; The Robley Rex Veterans Affairs Medical Center, Louisville, KY 40206, USA; The Jewish Hospital Liver Transplant Program, Louisville, KY 40202, USA; Hepatobiology & Toxicology Center, University of Louisville School of Medicine, Louisville, KY 40202, USA; University of Louisville Alcohol Research Center, University of Louisville, Louisville, KY 40202, USA; University of Louisville Superfund Research Program, University of Louisville, Louisville, KY 40202, USA.
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29
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Ahd K, Dhibi S, Akermi S, Bouzenna H, Samout N, Elfeki A, Hfaiedh N. Protective effect of ginger ( Zingiber officinale) against PCB-induced acute hepatotoxicity in male rats. RSC Adv 2019; 9:29120-29130. [PMID: 35528415 PMCID: PMC9071811 DOI: 10.1039/c9ra03136g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 07/23/2019] [Indexed: 11/29/2022] Open
Abstract
After absorption by the organism, polychlorinated biphenyls (PCBs) cross cellular membranes and pass into blood vessels and the lymphatic system. It is generally in the liver, adipose tissues, brain and skin that we find the strongest concentrations of PCBs. Herbal medicine remains as a discipline intended to treat and to prevent certain functional disorders and/or pathologies caused by oxidative stress, which can be induced by pesticides, medicines or pollutants. The objective of this study is to verify the toxic and oxidative effects of PCBs and to investigate the protective effect of ginger (Zingiber officinale) in the liver of male rats of the “Wistar” strain. These rats are divided into 6 groups: a control group (T), two groups treated with PCB at two different concentrations (P1 and P2), a group treated with ginger extract (G), a group pretreated with ginger extract and then injected with the first concentration of PCBs (P1G), and a group pretreated with ginger and then injected with the second concentration of PCBs (P2G). The results showed that the administration of PCBs led to an increase in the relative weight of the liver, and a significant increase in all of the hepatic biomarker levels (glucose, cholesterol, triglycerides, AST, ALT, and LDH) in the serum. Furthermore, an increase in the rate of lipid peroxidation and a decrease in the antioxidant enzyme activities (catalase, superoxide dismutase and glutathione peroxidase) were observed under the influence of PCBs in the liver. The histological test showed that the PCBs induced hepatocyte vacuolization, prominent and peripheralized nuclei, hepatocellular hypertrophy and turgor of the vein in the centriacinar regions. Pretreatment with ginger extract restored all of the biochemical and oxidative parameters to the normal values and reduced the injuries caused by the PCBs. In conclusion, in our experimental conditions, ginger effectively protects the liver against the hepatotoxic effects induced by PCBs. After absorption by the organism, polychlorinated biphenyls (PCBs) cross cellular membranes and pass into blood vessels and the lymphatic system.![]()
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Affiliation(s)
- Khedher Ahd
- Unity of Macromolecular Biochemistry and Genetics Faculty of Sciences
- Gafsa
- Tunisia
| | - Sabah Dhibi
- Unity of Macromolecular Biochemistry and Genetics Faculty of Sciences
- Gafsa
- Tunisia
- Laboratory of Environmental Physiopathology
- Valorization of Bioactive Molecules and Mathematical Modeling
| | - Sarra Akermi
- Unity of Macromolecular Biochemistry and Genetics Faculty of Sciences
- Gafsa
- Tunisia
- Laboratory of Environmental Physiopathology
- Valorization of Bioactive Molecules and Mathematical Modeling
| | - Hafsia Bouzenna
- Unity of Macromolecular Biochemistry and Genetics Faculty of Sciences
- Gafsa
- Tunisia
- Laboratory of Environmental Physiopathology
- Valorization of Bioactive Molecules and Mathematical Modeling
| | - Noura Samout
- Unity of Macromolecular Biochemistry and Genetics Faculty of Sciences
- Gafsa
- Tunisia
- Laboratory of Environmental Physiopathology
- Valorization of Bioactive Molecules and Mathematical Modeling
| | - Abdelfattah Elfeki
- Laboratory of Environmental Physiopathology
- Valorization of Bioactive Molecules and Mathematical Modeling
- Faculty of Sciences of Sfax
- Sfax
- Tunisia
| | - Najla Hfaiedh
- Unity of Macromolecular Biochemistry and Genetics Faculty of Sciences
- Gafsa
- Tunisia
- Laboratory of Environmental Physiopathology
- Valorization of Bioactive Molecules and Mathematical Modeling
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30
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Affiliation(s)
- Teresa L. Mako
- Department of Chemistry, University of Rhode Island, 140 Flagg Road, Kingston, Rhode Island 02881, United States
| | - Joan M. Racicot
- Department of Chemistry, University of Rhode Island, 140 Flagg Road, Kingston, Rhode Island 02881, United States
| | - Mindy Levine
- Department of Chemistry, University of Rhode Island, 140 Flagg Road, Kingston, Rhode Island 02881, United States
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31
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Environmental pollutant-mediated disruption of gut microbial metabolism of the prebiotic inulin. Anaerobe 2018; 55:96-102. [PMID: 30447394 DOI: 10.1016/j.anaerobe.2018.11.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 11/12/2018] [Accepted: 11/14/2018] [Indexed: 12/14/2022]
Abstract
Exposure to environmental pollutants is associated with a greater risk for metabolic diseases including cardiovascular disease. Pollutant exposure can also alter gut microbial populations that may contribute to metabolic effects and progression of inflammatory diseases. Short-chain fatty acids (SCFAs), produced from gut fermentation of dietary carbohydrates, such as inulin, exert numerous effects on host energy metabolism and are linked to a reduced risk of diseases. The hypothesis was that exposure to dioxin-like pollutants modulate gut microbial viability and/or fermentation processes. An inulin-utilizing isolate was collected from murine feces, characterized and used in subsequent experiments. Exposure to polychlorinated biphenyl, PCB 126 impeded bacterial viability of the isolate at concentrations of 20 and 200 μM. PCB 126 exposure also resulted in a significant loss of intracellular potassium following exposure, indicating cell membrane disruption of the isolate. Furthermore, total fecal microbe samples from mice were harvested, resuspended and incubated for 24 h in anaerobic media containing inulin with or without PCB 126. HPLC analysis of supernatants revealed that PCB 126 exposure reduced succinic acid production, but increased propionate production, both of which can influence host glucose and lipid metabolism. Overall, the presented evidence supports the idea that pollutant exposure may contribute to alterations in host metabolism through gut microbiota-dependent mechanisms, specifically through bacterial fermentation processes or membrane disruption.
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32
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Guo J, Wang C, Guo Z, Zuo Z. Exposure to environmental level phenanthrene induces a NASH-like phenotype in new born rat. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 239:261-271. [PMID: 29656250 DOI: 10.1016/j.envpol.2018.04.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 03/25/2018] [Accepted: 04/06/2018] [Indexed: 06/08/2023]
Abstract
More and more evidence indicates that persistent organic pollutants (POPs) are a risk factor for non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH). Phenanthrene (Phe) is a kind of POP which existed extensively in the environment, but whose toxicity on mammals has so far received less focus. Subcutaneously injection of Phe (0.5, 5, 50 μg/kg) for 21 days induced significant NAFLD/NASH symptoms in new born rats. Exposure to environmental levels of Phe decreased body weight and liver-somatic index; impaired histology of liver; influenced the peroxisome proliferator-activated receptor gamma (PPARγ) signaling and lipid metabolism in liver; stimulated oxidative stress in the rats' liver; induced the variation of NFκB pathway and liver inflammatory response; and caused liver fibrosis via transforming growth factor β1 (tgfβ1). We speculated that the subcutaneously injected Phe was transferred to the liver through blood circulation, which may have induced the elevation of PPARγ directly or indirectly, leading to liver steatosis. Excess lipid, acting as the first hit, stimulated the second hit factors - oxidative stress, inflammatory response and lipid peroxidation, and finally resulted in steatohepatitis and liver fibrosis.
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Affiliation(s)
- Jiaojiao Guo
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, 361005, China
| | - Chonggang Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, 361005, China; State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361005, China
| | - Zhizhun Guo
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, 361005, China
| | - Zhenghong Zuo
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, 361005, China; State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361005, China.
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33
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Wahlang B, Barney J, Thompson B, Wang C, Hamad OM, Hoffman JB, Petriello MC, Morris AJ, Hennig B. Editor's Highlight: PCB126 Exposure Increases Risk for Peripheral Vascular Diseases in a Liver Injury Mouse Model. Toxicol Sci 2018; 160:256-267. [PMID: 28973532 DOI: 10.1093/toxsci/kfx180] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The liver is vital for xenobiotic and endobiotic metabolism. Previously, we demonstrated that a compromised liver worsened toxicity associated with exposure to polychlorinated biphenyls (PCBs), through disruption of energy homeostasis. However, the role of a compromised liver in defining dioxin-like PCB126 toxicity on the peripheral vasculature and associated inflammatory diseases is yet to be studied. This study investigated the effects of PCB126 on vascular inflammation linked to hepatic dysfunction utilizing a liver injury mouse model. Male C57Bl/6 mice were fed either an amino acid control diet (CD) or a methionine-choline deficient (MCD) diet in this 14-week study. Mice were exposed to PCB126 (0.5 mg/kg) and analyzed for inflammatory, calorimetric and metabolic parameters. MCD diet-fed mice demonstrated steatosis, indicative of a compromised liver. Mice fed the MCD-diet and subsequently exposed to PCB126 manifested lower body fat mass, increased liver to body weight ratio and alterations in hepatic gene expression related to lipid and carbohydrate metabolism, implicating metabolic disturbances. PCB126-induced steatosis irrespective of the diet type, but only the MCD + PCB126 group exhibited steatohepatitis and fibrosis. Furthermore, PCB126 exposure in MCD-fed mice led to increased plasma inflammatory markers such as Icam-1, plasminogen activator inhibitor-1 and proatherogenic trimethylamine-N-oxide, suggesting inflammation of the peripheral vasculature that is characteristic of atherosclerosis. Taken together, our data provide new evidence of a link between a compromised liver, PCB-mediated hepatic inflammation and vascular inflammatory markers, suggesting that environmental pollutants can promote crosstalk between different organ systems, leading to inflammatory disease pathologies.
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Affiliation(s)
- Banrida Wahlang
- University of Kentucky Superfund Research Center.,Department of Animal and Food Sciences, College of Agriculture, Food and Environment
| | - Jazmyne Barney
- University of Kentucky Superfund Research Center.,Department of Toxicology and Cancer Biology, College of Medicine
| | - Brendan Thompson
- University of Kentucky Superfund Research Center.,Department of Toxicology and Cancer Biology, College of Medicine
| | - Chunyan Wang
- University of Kentucky Superfund Research Center.,Department of Animal and Food Sciences, College of Agriculture, Food and Environment
| | - Omer M Hamad
- University of Kentucky Superfund Research Center
| | - Jessie B Hoffman
- University of Kentucky Superfund Research Center.,Graduate Center for Nutritional Sciences, College of Medicine
| | - Michael C Petriello
- University of Kentucky Superfund Research Center.,Division of Cardiovascular Medicine, College of Medicine, University of Kentucky, Lexington, Kentucky 40536.,Lexington Veterans Affairs Medical Center, Lexington, Kentucky
| | - Andrew J Morris
- University of Kentucky Superfund Research Center.,Division of Cardiovascular Medicine, College of Medicine, University of Kentucky, Lexington, Kentucky 40536.,Lexington Veterans Affairs Medical Center, Lexington, Kentucky
| | - Bernhard Hennig
- University of Kentucky Superfund Research Center.,Department of Animal and Food Sciences, College of Agriculture, Food and Environment.,Department of Toxicology and Cancer Biology, College of Medicine.,Graduate Center for Nutritional Sciences, College of Medicine
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34
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Ahmed R. Endocrine Disruptors; Possible Mechanisms for Inducing Developmental Disorders. INTERNATIONAL JOURNAL OF BASIC SCIENCE IN MEDICINE 2017. [DOI: 10.15171/ijbsm.2017.29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- R.G. Ahmed
- Division of Anatomy and Embryology, Zoology Department, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt
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35
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Hoffman JB, Hennig B. Protective influence of healthful nutrition on mechanisms of environmental pollutant toxicity and disease risks. Ann N Y Acad Sci 2017; 1398:99-107. [PMID: 28574588 DOI: 10.1111/nyas.13365] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 03/29/2017] [Accepted: 04/06/2017] [Indexed: 12/21/2022]
Abstract
Human exposures to environmental contaminants around the world contribute to the global burden of disease and thus require urgent attention. Exploring preventive measures against environmental exposure and disease risk is essential. While a sedentary lifestyle and/or poor dietary habits can exacerbate the deleterious effects resulting from exposure to toxic chemicals, much emerging evidence suggests that positive lifestyle changes (e.g., healthful nutrition) can modulate and/or reduce the toxicity of environmental pollutants. Our work has shown that diets high in anti-inflammatory bioactive food components (e.g., phytochemicals or polyphenols) are possible strategies for modulating and reducing the disease risks associated with exposure to toxic pollutants in the environment. Thus, consuming healthy diets rich in plant-derived bioactive nutrients may reduce the vulnerability to diseases linked to environmental toxic insults. This nutritional paradigm in environmental toxicology requires further study in order to improve our understanding of the relationships between nutrition and other lifestyle modifications and toxicant-induced diseases.
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Affiliation(s)
- Jessie B Hoffman
- Superfund Research Center, University of Kentucky, Lexington, Kentucky.,Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, Kentucky
| | - Bernhard Hennig
- Superfund Research Center, University of Kentucky, Lexington, Kentucky.,Department of Animal and Food Sciences, College of Agriculture, Food and Environment, University of Kentucky, Lexington, Kentucky
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