EZH2 Alleviates Antituberculosis Drug-Induced Liver Injury in Mice by Reducing H3K27 Trimethylation at the Nrf2 Promoter

Abstract BackgroundAnti-tuberculosis drug-induced liver injury (ADLI) limits the treatment of tuberculosis. The mechanisms underlying ADLI are unclear and there are no effective preventative measures to avoid this complication. MethodsIn this stuy, the protein contents of EZH2, Nrf2, NQO1 and HO-1 were detected by ELISA kit, while those of EZH2 and Nrf2 were determined by Western blot. The Chip experiment was used to detect the level of H3K27me3 in the Nrf2 promoter region.The liver were analyzed histopathologically in vivo using hematoxylin and eosin staining.ResultsHere we developed a murine model of ADLI that recapitulates liver injury in the human disease. Using this model, we investigated the potential involvement of the enhancer of zeste homolog 2 methyltransferase (EZH2), a histone methyltransferase which inhibits the transcriptional activation of the Nrf2-ARE oxidative stress pathway. Compared to controls, mice livers with ADLI showed decreased expression of EZH2 together with reduced H3K27me3 marks in the Nrf2 promoter. This was accompanied by increased expression of Nrf2 and its target genes NQO1 and HO-1. Liver injury in the mice with ADLI could be alleviated to an extent by in vivo delivery of siRNAs targeting EZH2, which further downregulated EZH2 expression and H3K27me3 levels in the Nrf2 promoter along with accompanying increases in Nrf2, NQO1 and HO-1 expression. ConclusionsTherefore, inhibiting EZH2 likely reduced liver damage in ADLI by enhancing this key anti-oxidative stress pathway. Our results establish a role for EZH2 in a mouse model of ADLI and furthermore provides valuable mechanistic insights into the development of ADLI pathology.

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Transcriptional Inhibitors Identified in a 160,000-Compound Small-Molecule DUX4 Viability Screen

CrossRef Listing of Deleted DOIs ◽

10.1177/1087057116651868 ◽

2016 ◽

Vol 21 (7) ◽

pp. 680-688 ◽

Cited By ~ 7

Author(s):

Si Ho Choi ◽

Darko Bosnakovski ◽

Jessica M. Strasser ◽

Erik A. Toso ◽

Michael A. Walters ◽

...

Keyword(s):

Oxidative Stress ◽

Muscular Dystrophy ◽

Transcriptional Activation ◽

Target Gene ◽

Target Genes ◽

Facioscapulohumeral Muscular Dystrophy ◽

Oxidative Stress Pathway ◽

Nonspecific Effects ◽

Stress Pathway ◽

Mouse Myoblast

Facioscapulohumeral muscular dystrophy is a genetically dominant, currently untreatable muscular dystrophy. It is caused by mutations that enable expression of the normally silent DUX4 gene, which encodes a pathogenic transcription factor. A screen based on Tet-on DUX4-induced mouse myoblast death previously uncovered compounds from a 44,000-compound library that protect against DUX4 toxicity. Many of those compounds acted downstream of DUX4 in an oxidative stress pathway. Here, we extend this screen to an additional 160,000 compounds and, using greater stringency, identify a new set of DUX4-protective compounds. From 640 hits, we performed secondary screens, repurchased 46 of the most desirable, confirmed activity, and tested each for activity against other cell death–inducing insults. The majority of these compounds also protected against oxidative stress. Of the 100 repurchased compounds identified through both screens, only SHC40, 75, and 98 inhibited DUX4 target genes, but they also inhibited dox-mediated DUX4 expression. Using a target gene readout on the 640-compound hit set, we discovered three overlooked compounds, SHC351, 540, and 572, that inhibit DUX4 target gene upregulation without nonspecific effects on the Tet-on system. These novel inhibitors of DUX4 transcriptional activity may thus act on pathways or cofactors needed by DUX4 for transcriptional activation in these cells.

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Drug-induced liver injury classification model based on in vitro human transcriptomics and in vivo rat clinical chemistry data

Systems Biomedicine ◽

10.4161/sysb.29400 ◽

2014 ◽

Vol 2 (4) ◽

pp. 63-70 ◽

Cited By ~ 10

Author(s):

Danyel Jennen ◽

Jan Polman ◽

Mark Bessem ◽

Maarten Coonen ◽

Joost van Delft ◽

...

Keyword(s):

Liver Injury ◽

Clinical Chemistry ◽

Classification Model ◽

Drug Induced ◽

Drug Induced Liver Injury ◽

Chemistry Data ◽

Model Based ◽

Injury Classification

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Isoniazid and Rifampicin Produce Hepatic Fibrosis through an Oxidative Stress-Dependent Mechanism

International Journal of Hepatology ◽

10.1155/2020/6987295 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Ayan Biswas ◽

Suman Santra ◽

Debasree Bishnu ◽

Gopal Krishna Dhali ◽

Abhijit Chowdhury ◽

...

Keyword(s):

Oxidative Stress ◽

Liver Injury ◽

Hepatic Fibrosis ◽

Stellate Cell ◽

Progressive Increase ◽

Drug Induced ◽

Drug Induced Liver Injury ◽

Stress Dependent ◽

Liver Collagen

Background & Aims. Chronic hepatitis (CH) has emerged as a distinct outcome of drug-induced liver injury (DILI). Combination therapy of Isoniazid (INH) and Rifampicin (RMP) which is widely used for prolonged periods can cause acute hepatotoxicity and has been also incriminated in chronic DILI. We sought evidence of the production of hepatic fibrosis on long-term INH-RMP treatment through experiments in BALB/c mice exposed to INH-RMP. Methods. A combined dose of INH (50 mg) and RMP (100 mg) per kg body weight per day was administered to mice by oral gavage, 6 days a week, for 4 to 24 weeks for the assessment of liver injury, oxidative stress, and development of hepatic fibrosis, including demonstration of changes in key fibrogenesis linked pathways and mediators. Results. Progressive increase in markers of hepatic stellate cell (HSC) activation associated with changes in matrix turnover was observed between 12 and 24 weeks of INH-RMP treatment along with the elevation of liver collagen content and significant periportal fibrosis. These were associated with concurrent apoptosis of the hepatocytes, increase in hepatic cytochrome P450 2E1 (CYP2E1), NADPH oxidase (NOX) activity, and development of hepatic oxidative stress. Conclusions. INH-RMP can activate HSC through generation of NOX-mediated oxidative stress, leading to the development of liver fibrosis.

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Lighting up alkaline phosphatase in drug-induced liver injury using a new chemiluminescence resonance energy transfer nanoprobe

Chemical Communications ◽

10.1039/c8cc07211f ◽

2018 ◽

Vol 54 (88) ◽

pp. 12479-12482 ◽

Cited By ~ 17

Author(s):

Xueting Liu ◽

Nannan Fan ◽

Lijie Wu ◽

Chuanchen Wu ◽

Yongqing Zhou ◽

...

Keyword(s):

Alkaline Phosphatase ◽

Energy Transfer ◽

Liver Injury ◽

Alkaline Phosphatase Level ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Drug Induced ◽

Drug Induced Liver Injury

Ultra-sensitive imaging of the alkaline phosphatase levelin vivoin drug-induced liver injury with a new chemiluminescence resonance energy transfer nanoprobe.

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Ginsenoside Rb1, A Major Saponin from Panax ginseng, Exerts Protective Effects Against Acetaminophen-Induced Hepatotoxicity in Mice

The American Journal of Chinese Medicine ◽

10.1142/s0192415x19500927 ◽

2019 ◽

Vol 47 (08) ◽

pp. 1815-1831 ◽

Cited By ~ 4

Author(s):

Shen Ren ◽

Jing Leng ◽

Xing-Yue Xu ◽

Shuang Jiang ◽

Ying-Ping Wang ◽

...

Keyword(s):

Liver Injury ◽

Panax Ginseng ◽

Inflammatory Responses ◽

Interleukin 1 ◽

Protective Effects ◽

Ginsenoside Rb1 ◽

Drug Induced ◽

Drug Induced Liver Injury ◽

Oxide Synthase

Acute liver injury (ALI) induced by acetaminophen (APAP) is the main cause of drug-induced liver injury. Previous reports indicated liver failure could be alleviated by saponins (ginsenosides) from Panax ginseng against APAP-induced inflammatory responses in vivo. However, validation towards ginsenoside Rb1 as a major and marker saponin may protect liver from APAP-induced ALI and its mechanisms are poorly elucidated. In this study, the protective effects and the latent mechanisms of Rb1 action against APAP-induced hepatotoxicity were investigated. Rb1 was administered orally with 10[Formula: see text]mg/kg and 20[Formula: see text]mg/kg daily for 1 week before a single injection of APAP (250[Formula: see text]mg/kg, i.p.) 1[Formula: see text]h after the last treatment of Rb1. Serum alanine/aspartate aminotransferases (ALT/AST), liver glutathione (GSH) depletion, as well as the inflammatory cytokines, such as tumor necrosis factor-[Formula: see text] (TNF-[Formula: see text]), interleukin-1[Formula: see text] (IL-1[Formula: see text]), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), were analyzed to indicate the underlying protective effects of Rb1 against APAP-induced hepatotoxicity with significant inflammatory responses. Histological examination further proved Rb1’s protective effects. Importantly, Rb1 mitigated the changes in the phosphorylation of MAPK and PI3K/Akt, as well as its downstream factor NF-[Formula: see text]B. In conclusion, experimental data clearly demonstrated that Rb1 exhibited a remarkable liver protective effect against APAP-induced ALI, partly through regulating MAPK and PI3K/Akt signaling pathways-mediated inflammatory responses.

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Zucker Lean Rats With Hepatic Steatosis Recapitulate Asymptomatic Metabolic Syndrome and Exhibit Greater Sensitivity to Drug-Induced Liver Injury Compared With Standard Nonclinical Sprague-Dawley Rat Model

Toxicologic Pathology ◽

10.1177/0192623320968716 ◽

2020 ◽

Vol 48 (8) ◽

pp. 994-1007

Author(s):

Timothy P. LaBranche ◽

Anna K. Kopec ◽

Srinivasa R. Mantena ◽

Brett D. Hollingshead ◽

Andrew W. Harrington ◽

...

Keyword(s):

Metabolic Syndrome ◽

Pharmaceutical Industry ◽

Liver Injury ◽

Hepatic Steatosis ◽

Sprague Dawley ◽

Drug Induced ◽

Drug Induced Liver Injury ◽

Sd Rats ◽

Normal Chow

Fatty liver disease is a potential risk factor for drug-induced liver injury (DILI). Despite advances in nonclinical in vitro and in vivo models to assess liver injury during drug development, the pharmaceutical industry is still plagued by idiosyncratic DILI. Here, we tested the hypothesis that certain features of asymptomatic metabolic syndrome (namely hepatic steatosis) increase the risk for DILI in certain phenotypes of the human population. Comparison of the Zucker Lean (ZL) and Zucker Fatty rats fed a high fat diet (HFD) revealed that HFD-fed ZL rats developed mild hepatic steatosis with compensatory hyperinsulinemia without increases in liver enzymes. We then challenged steatotic HFD-fed ZL rats and Sprague-Dawley (SD) rats fed normal chow, a nonclinical model widely used in the pharmaceutical industry, with acetaminophen overdose to induce liver injury. Observations in HFD-fed ZL rats included increased liver injury enzymes and greater incidence and severity of hepatic necrosis compared with similarly treated SD rats. The HFD-fed ZL rats also had disproportionately higher hepatic drug accumulation, which was linked with abnormal hepatocellular efflux transporter distribution. Here, we identify ZL rats with HFD-induced hepatic steatosis as a more sensitive nonclinical in vivo test system for modeling DILI compared with SD rats fed normal chow.

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Current Perspective: 3D Spheroid Models Utilizing Human-Based Cells for Investigating Metabolism-Dependent Drug-Induced Liver Injury

Frontiers in Medical Technology ◽

10.3389/fmedt.2020.611913 ◽

2020 ◽

Vol 2 ◽

Author(s):

Christopher R. Cox ◽

Stephen Lynch ◽

Christopher Goldring ◽

Parveen Sharma

Keyword(s):

Liver Injury ◽

Pharmaceutical Companies ◽

Drug Induced ◽

Drug Induced Liver Injury ◽

Current Perspective ◽

Dosing Regimens ◽

Underlying Mechanisms ◽

Approved Drugs

Drug-induced liver injury (DILI) remains a leading cause for the withdrawal of approved drugs. This has significant financial implications for pharmaceutical companies, places increasing strain on global health services, and causes harm to patients. For these reasons, it is essential that in-vitro liver models are capable of detecting DILI-positive compounds and their underlying mechanisms, prior to their approval and administration to patients or volunteers in clinical trials. Metabolism-dependent DILI is an important mechanism of drug-induced toxicity, which often involves the CYP450 family of enzymes, and is associated with the production of a chemically reactive metabolite and/or inefficient removal and accumulation of potentially toxic compounds. Unfortunately, many of the traditional in-vitro liver models fall short of their in-vivo counterparts, failing to recapitulate the mature hepatocyte phenotype, becoming metabolically incompetent, and lacking the longevity to investigate and detect metabolism-dependent DILI and those associated with chronic and repeat dosing regimens. Nevertheless, evidence is gathering to indicate that growing cells in 3D formats can increase the complexity of these models, promoting a more mature-hepatocyte phenotype and increasing their longevity, in vitro. This review will discuss the use of 3D in vitro models, namely spheroids, organoids, and perfusion-based systems to establish suitable liver models to investigate metabolism-dependent DILI.

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TAMH: A Useful In Vitro Model for Assessing Hepatotoxic Mechanisms

BioMed Research International ◽

10.1155/2016/4780872 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

Madison Davis ◽

Brendan D. Stamper

Keyword(s):

Liver Injury ◽

Transforming Growth Factor ◽

Chemical Exposure ◽

Health Concern ◽

Hepatocellular Injury ◽

Drug Induced ◽

Endogenous Factors ◽

Drug Induced Liver Injury

In vitro models for hepatotoxicity can be useful tools to predict in vivo responses. In this review, we discuss the use of the transforming growth factor-αtransgenic mouse hepatocyte (TAMH) cell line, which is an attractive model to study drug-induced liver injury due to its ability to retain a stable phenotype and express drug-metabolizing enzymes. Hepatotoxicity involves damage to the liver and is often associated with chemical exposure. Since the liver is a major site for drug metabolism, drug-induced liver injury is a serious health concern for certain agents. At the molecular level, various mechanisms may protect or harm the liver during drug-induced hepatocellular injury including signaling pathways and endogenous factors (e.g., Bcl-2, GSH, Nrf2, or MAPK). The interplay between these and other pathways in the hepatocyte can change upon drug or drug metabolite exposure leading to intracellular stress and eventually cell death and liver injury. This review focuses on mechanistic studies investigating drug-induced toxicity in the TAMH line and how alterations to hepatotoxic mechanisms in this model relate to the in vivo situation. The agents discussed herein include acetaminophen (APAP), tetrafluoroethylcysteine (TFEC), flutamide, PD0325901, lapatinib, and flupirtine.

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