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Parafati M, Kirby RJ, Khorasanizadeh S, Rastinejad F, Malany S. A nonalcoholic fatty liver disease model in human induced pluripotent stem cell-derived hepatocytes, created by endoplasmic reticulum stress-induced steatosis. Dis Model Mech 2018; 11:11/9/dmm033530. [PMID: 30254132 PMCID: PMC6176998 DOI: 10.1242/dmm.033530] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 08/08/2018] [Indexed: 12/14/2022] Open
Abstract
Hepatic steatosis, a reversible state of metabolic dysregulation, can promote the onset of nonalcoholic steatohepatitis (NASH), and its transition is thought to be critical in disease evolution. The association between endoplasmic reticulum (ER) stress response and hepatocyte metabolism disorders prompted us to characterize ER stress-induced hepatic metabolic dysfunction in human induced pluripotent stem cell-derived hepatocytes (hiPSC-Hep), to explore regulatory pathways and validate a phenotypic in vitro model for progression of liver steatosis. We treated hiPSC-Hep with a ratio of unsaturated and saturated fatty acids in the presence of an inducer of ER stress to synergistically promote triglyceride accumulation and dysregulate lipid metabolism. We monitored lipid accumulation by high-content imaging and measured gene regulation by RNA sequencing and reverse transcription quantitative PCR analyses. Our results show that ER stress potentiated intracellular lipid accumulation by 5-fold in hiPSC-Hep in the absence of apoptosis. Transcriptome pathway analysis identified ER stress pathways as the most significantly dysregulated of all pathways affected. Obeticholic acid dose dependently inhibited lipid accumulation and modulated gene expression downstream of the farnesoid X receptor. We were able to identify modulation of hepatic markers and gene pathways known to be involved in steatosis and nonalcoholic fatty liver disease (NAFLD), in support of a hiPSC-Hep disease model that is relevant to clinical data for human NASH. Our results show that the model can serve as a translational discovery platform for the understanding of molecular pathways involved in NAFLD, and can facilitate the identification of novel therapeutic molecules based on high-throughput screening strategies. Summary: Our study demonstrates expanded use of human induced pluripotent stem cell-derived hepatocytes for molecular studies and drug screening, to evaluate new therapeutics with an antisteatotic mechanism of action for nonalcoholic fatty liver disease.
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Affiliation(s)
- Maddalena Parafati
- Translational Biology, Conrad Prebys Center for Chemical Genomics, Orlando, FL 32827, USA
| | - R Jason Kirby
- Translational Biology, Conrad Prebys Center for Chemical Genomics, Orlando, FL 32827, USA
| | - Sepideh Khorasanizadeh
- Center for Metabolic Origins of Disease, Sanford Burham Prebys Medical Discovery Institute, 6400 Sanger Rd, Orlando, FL 32827, USA
| | - Fraydoon Rastinejad
- Center for Metabolic Origins of Disease, Sanford Burham Prebys Medical Discovery Institute, 6400 Sanger Rd, Orlando, FL 32827, USA
| | - Siobhan Malany
- Translational Biology, Conrad Prebys Center for Chemical Genomics, Orlando, FL 32827, USA
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102
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Huang LS, Yuen JJ, Trites MJ, Saha A, Epps CT, Hu Y, Kerolle S, Lee SA, Jiang H, Goldberg IJ, Blaner WS, Clugston RD. Dietary Macronutrient Composition Determines the Contribution of DGAT1 to Alcoholic Steatosis. Alcohol Clin Exp Res 2018; 42:2298-2312. [PMID: 30192394 PMCID: PMC6286229 DOI: 10.1111/acer.13881] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 09/02/2018] [Indexed: 01/01/2023]
Abstract
Background The first stage of alcoholic liver disease is hepatic steatosis. While alcohol is known to profoundly impact hepatic lipid metabolism, gaps in our knowledge remain regarding the mechanisms leading to alcohol‐induced hepatic triglyceride (TG) accumulation. As the sole enzymes catalyzing the final step in TG synthesis, diacylglycerol O‐acyltransferase (DGAT) 1 and 2 are potentially important contributors to alcoholic steatosis. Our goal was to study the effects of dietary fat content on alcohol‐induced hepatic TG accumulation, and the relative contribution of DGAT1 and DGAT2 to alcoholic steatosis. Methods These studies were carried out in wild‐type (WT) mice fed alcohol‐containing high‐fat or low‐fat formulations of Lieber‐DeCarli liquid diets, as well as follow‐up studies in Dgat1−/− mice. Results A direct comparison of the low‐fat and high‐fat liquid diet in WT mice revealed surprisingly similar levels of alcoholic steatosis, although there were underlying differences in the pattern of hepatic lipid accumulation and expression of genes involved in hepatic lipid metabolism. Follow‐up studies in Dgat1−/− mice revealed that these animals are protected from alcoholic steatosis when consumed as part of a high‐fat diet, but not a low‐fat diet. Conclusions Dietary macronutrient composition influences the relative contribution of DGAT1 and DGAT2 to alcoholic steatosis, such that in the context of alcohol and a high‐fat diet, DGAT1 predominates.
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Affiliation(s)
- Li-Shin Huang
- Department of Medicine, Columbia University, New York, New York
| | - Jason J Yuen
- Department of Medicine, Columbia University, New York, New York
| | - Michael J Trites
- Department of Physiology, University of Alberta, Edmonton, AB, Canada
| | - Amit Saha
- Department of Medicine, Columbia University, New York, New York
| | - Caleb T Epps
- Department of Medicine, Columbia University, New York, New York
| | - Yungying Hu
- Department of Medicine, New York University Langone Medical Center, New York, New York
| | | | - Seung-Ah Lee
- Department of Medicine, Columbia University, New York, New York
| | - Hongfeng Jiang
- Department of Medicine, Columbia University, New York, New York
| | - Ira J Goldberg
- Department of Medicine, New York University Langone Medical Center, New York, New York
| | | | - Robin D Clugston
- Department of Physiology, University of Alberta, Edmonton, AB, Canada
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103
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Bhatt-Wessel B, Jordan TW, Miller JH, Peng L. Role of DGAT enzymes in triacylglycerol metabolism. Arch Biochem Biophys 2018; 655:1-11. [PMID: 30077544 DOI: 10.1016/j.abb.2018.08.001] [Citation(s) in RCA: 107] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 07/25/2018] [Accepted: 08/02/2018] [Indexed: 01/22/2023]
Abstract
The esterification of a fatty acyl moiety to diacylglycerol to form triacylglycerol (TAG) is catalysed by two diacylglycerol O-acyltransferases (DGATs) encoded by genes belonging to two distinct gene families. The enzymes are referred to as DGAT1 and DGAT2 in order of their identification. Both proteins are transmembrane proteins localized in the endoplasmic reticulum. Their membrane topologies are however significantly different. This difference is hypothesized to give the two isozymes different abilities to interact with other proteins and organelles and access to different pools of fatty acids, thereby creating a distinction between the enzymes in terms of their role and contribution to lipid metabolism. DGAT1 is proposed to have dual topology contributing to TAG synthesis on both sides of the ER membrane and esterifying only the pre-formed fatty acids. There is evidence to suggest that DGAT2 translocates to the lipid droplet (LD), associates with other proteins, and synthesizes cytosolic and luminal apolipoprotein B associated LD-TAG from both endogenous and exogenous fatty acids. The aim of this review is to differentiate between the two DGAT enzymes by comparing the genes that encode them, their proposed topologies, the proteins they interact with, and their roles in lipid metabolism.
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Affiliation(s)
- Bhumika Bhatt-Wessel
- Centre for Biodiscovery and School of Biological Sciences, Victoria University of Wellington, New Zealand
| | - T William Jordan
- Centre for Biodiscovery and School of Biological Sciences, Victoria University of Wellington, New Zealand
| | - John H Miller
- Centre for Biodiscovery and School of Biological Sciences, Victoria University of Wellington, New Zealand
| | - Lifeng Peng
- Centre for Biodiscovery and School of Biological Sciences, Victoria University of Wellington, New Zealand.
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104
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McLaren DG, Han S, Murphy BA, Wilsie L, Stout SJ, Zhou H, Roddy TP, Gorski JN, Metzger DE, Shin MK, Reilly DF, Zhou HH, Tadin-Strapps M, Bartz SR, Cumiskey AM, Graham TH, Shen DM, Akinsanya KO, Previs SF, Imbriglio JE, Pinto S. DGAT2 Inhibition Alters Aspects of Triglyceride Metabolism in Rodents but Not in Non-human Primates. Cell Metab 2018; 27:1236-1248.e6. [PMID: 29706567 DOI: 10.1016/j.cmet.2018.04.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2017] [Revised: 01/12/2018] [Accepted: 04/02/2018] [Indexed: 11/18/2022]
Abstract
Diacylglycerol acyltransferase 2 (DGAT2) catalyzes the final step in triglyceride (TG) synthesis and has been shown to play a role in regulating hepatic very-low-density lipoprotein (VLDL) production in rodents. To explore the potential of DGAT2 as a therapeutic target for the treatment of dyslipidemia, we tested the effects of small-molecule inhibitors and gene silencing both in vitro and in vivo. Consistent with prior reports, chronic inhibition of DGAT2 in a murine model of obesity led to correction of multiple lipid parameters. In contrast, experiments in primary human, rhesus, and cynomolgus hepatocytes demonstrated that selective inhibition of DGAT2 has only a modest effect. Acute and chronic inhibition of DGAT2 in rhesus primates recapitulated the in vitro data yielding no significant effects on production of plasma TG or VLDL apolipoprotein B. These results call into question whether selective inhibition of DGAT2 is sufficient for remediation of dyslipidemia.
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Affiliation(s)
| | - Seongah Han
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA.
| | | | - Larissa Wilsie
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Steven J Stout
- Pharmacology, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Haihong Zhou
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Thomas P Roddy
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | | | | | - Myung K Shin
- Genetics and Pharmacogenomics, Merck & Co., Inc., Boston, MA 02115, USA
| | - Dermot F Reilly
- Genetics and Pharmacogenomics, Merck & Co., Inc., Boston, MA 02115, USA
| | - Heather H Zhou
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | | | - Steven R Bartz
- Business Development and Licensing, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | | | - Thomas H Graham
- Discovery Chemistry, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Dong-Ming Shen
- Discovery Chemistry, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Karen O Akinsanya
- Business Development and Licensing, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Stephen F Previs
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | | | - Shirly Pinto
- Division of Cardio Metabolic Disease, Merck & Co., Inc., Kenilworth, NJ 07033, USA.
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105
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Pérez-Martínez L, Ochoa-Callejero L, Rubio-Mediavilla S, Narro J, Bernardo I, Oteo JA, Blanco JR. Maraviroc improves hepatic triglyceride content but not inflammation in a murine nonalcoholic fatty liver disease model induced by a chronic exposure to high-fat diet. Transl Res 2018; 196:17-30. [PMID: 29421523 DOI: 10.1016/j.trsl.2018.01.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 12/19/2017] [Accepted: 01/16/2018] [Indexed: 01/11/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the general population. Its severity ranges from simple steatosis to cirrhosis. C-C chemokine ligand type 5 or RANTES (Regulated upon Activation, Normal T-cell Expressed, and Secreted) plays an important role in the progression of hepatic inflammation and fibrosis. Our objective was to examine the preventive and therapeutic effects of maraviroc (MVC), a C-C chemokine receptor 5 antagonist, on liver pathology in an NAFLD mouse model. A total of 60 male C57BL/6 mice were randomly assigned to 1 of 4 groups: (1) high-fat diet (HFD) group or control group, (2) preventive group (HFD group plus MVC in drinking water since the beginning of the study), (3) early-therapeutic group (HFD group plus MVC in drinking starting at week 24 of the study), and (4) late-therapeutic group (HFD group plus MVC in drinking water starting at week 36 of the study). All mice were sacrificed at week 48. The hepatic triglyceride concentration in the HFD group was significantly higher than that in the groups treated with MVC at any time. Gene expression associated with lipogenesis (diacylglycerol acyltransferase 2 and proliferator-activated receptor-γ), insulin resistance (insulin receptor substrate-2), and β-oxidation (carnitine palmitoyltransferase 1A and acyl-CoA oxidase) was significantly reduced in all the groups treated with MVC. In summary, the beneficial effect of MVC on hepatic steatosis is maintained throughout the study.
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Affiliation(s)
- Laura Pérez-Martínez
- Infectious Diseases Area, Center for Biomedical Research of La Rioja (CIBIR), Logroño, Spain
| | | | | | - Judit Narro
- Oncology Area, Center for Biomedical Research of La Rioja (CIBIR), Logroño, Spain
| | - Iván Bernardo
- Biomedical Diagnostic Service, Hospital San Pedro, Logroño, Spain
| | - José-Antonio Oteo
- Infectious Diseases Area, Center for Biomedical Research of La Rioja (CIBIR), Logroño, Spain
| | - José-Ramón Blanco
- Infectious Diseases Area, Center for Biomedical Research of La Rioja (CIBIR), Logroño, Spain.
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106
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Dallak MA. Acylated ghrelin induces but deacylated ghrelin prevents hepatic steatosis and insulin resistance in lean rats: Effects on DAG/ PKC/JNK pathway. Biomed Pharmacother 2018; 105:299-311. [PMID: 29860222 DOI: 10.1016/j.biopha.2018.05.098] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 05/20/2018] [Accepted: 05/21/2018] [Indexed: 12/19/2022] Open
Abstract
This study investigated the molecular effects of acylated (AG) and unacylated ghrelin (UAG) or their combination on hepatic lipogenesis pathways and DAG/PKC/JNK signaling in the livers of lean rats fed standard diet. Male rats (n = 10) were classified as control + vehicle (saline, 200 μl), AG, UAG, and AG + UAG-treated groups. All treatments were given at final doses of 200 ng/kg of for 14 days (twice/day, S.C). Administration of AG significantly enhanced circulatory levels of AG and UAG turning the normal ratio of AG/UAG from 1:2.5 to 1:1.2. However, while UAG didn't affect circulatory levels of AG, administration of UAG alone or in combination with AG resulted in AG/UAG ratios of 1:7 and 1:3, respectively. Independent of food intake nor the development of peripheral IR, AG increased hepatic DAG, TGs and CHOL contents and induced hepatic IR. Mechanism of action include 1) upregulation of mRNA and protein levels of DGAT-2 and mtGPAT-1, SREBP-1 and SCD-1, and 2) inhibition of fatty acids (FAs) oxidation mediated by inhibition of AMPK/ PPAR-α/CPT-1 axis. Consequently, AG induced membranous translocation of PKCδ and PKCε leading to activation of JNK and significant inhibition of insulin signaling under basal and insulin stimulation as evident by decreases in the phosphorylation levels of IRS (Tyr612) and Akt (Thr318) and increased phosphorylation of IRS (Ser307). However, while UAG only activated FAs oxidation in control rats, it reversed all alterations in all measured biochemical endpoints seen in the AG-treated group, when administered in combination with AG, leading to significant decreases in hepatic fat accumulation and prevention of hepatic IR. In conclusion, while exogenous administration of AG is at high risk of developing steatohepatitis and hepatic IR, co-administration of a balanced dose of UAG reduces this risk and inhibits hepatic lipid accumulation and enhance hepatic insulin signaling.
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Affiliation(s)
- Mohammad A Dallak
- Department of Physiology, College of Medicine, King's Khalid University, Abha, 61241, Saudi Arabia.
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107
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Dual extraction of mRNA and lipids from a single biological sample. Sci Rep 2018; 8:7019. [PMID: 29728575 PMCID: PMC5935724 DOI: 10.1038/s41598-018-25332-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 04/19/2018] [Indexed: 12/11/2022] Open
Abstract
The extraction of RNA and lipids from a large number of biological samples is time-consuming and costly with steps required for both transcriptomic and lipidomic approaches. Most protocols rely on independent extraction of nucleic acids and lipids from a single sample, thereby increasing the need for biological material and inducing variability in data analysis. We investigated whether it is possible to use a standard RNA extraction procedure to analyze not only RNA levels, but also lipids in a single liver sample. We show that the organic phase obtained when using standard reagents for RNA extraction can be used to analyze lipids, including neutral lipids and fatty acids, by gas chromatography. We applied this technique to an analysis of lipids and the associated gene expression pattern in mice with hepatic steatosis induced by pharmacological activation of nuclear receptor LXR.
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108
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Stahel P, Xiao C, Hegele RA, Lewis GF. The Atherogenic Dyslipidemia Complex and Novel Approaches to Cardiovascular Disease Prevention in Diabetes. Can J Cardiol 2018; 34:595-604. [DOI: 10.1016/j.cjca.2017.12.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 12/04/2017] [Accepted: 12/07/2017] [Indexed: 10/18/2022] Open
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109
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110
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Yasuno K, Kumagai K, Iguchi T, Tsuchiya Y, Kai K, Mori K. DS-7250, a Diacylglycerol Acyltransferase 1 Inhibitor, Enhances Hepatic Steatosis in Zucker Fatty Rats via Upregulation of Fatty Acid Synthesis. Toxicol Pathol 2018; 46:302-311. [PMID: 29587622 DOI: 10.1177/0192623318765909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Diacylglycerol acyltransferase 1 (DGAT1) catalyzes the final step in triglyceride synthesis. Since Dgat1-/- mice fed a high-fat diet (HFD) are resistant to hepatic steatosis, DGAT1 inhibitors are expected to have antifatty liver effects. To evaluate the hepatic effects of DS-7250, a selective DGAT1 inhibitor, vehicle or 10 mg/kg of DS-7250 was administered orally to male Fisher 344 (F344) and Zucker fatty (ZF) rats fed a standard diet or HFD for 14 or 28 days. ZF rats showed slight hepatic steatosis regardless of feeding conditions. DS-7250 exacerbated hepatic steatosis in ZF rats fed an HFD compared with the vehicle control. Hepatic steatosis did not occur in F344 rats fed an HFD, in which systemic exposures of DS-7250 were comparable to those in ZF rats. There was a higher expression of genes involved in lipid uptake and fatty acid synthesis in ZF rats compared to F344 rats under HFD conditions. DS-7250 upregulated key genes involved in de novo lipogenesis, which causes hepatic steatosis independently of DGAT1, in ZF rats fed an HFD compared with the vehicle control. These data suggest that ZF rats were more susceptible to hepatic steatosis due to their genetic characteristics and DS-7250 exacerbated hepatic steatosis independently of DGAT1.
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Affiliation(s)
- Kyohei Yasuno
- 1 Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., Edogawa, Tokyo, Japan
| | - Kazuyoshi Kumagai
- 1 Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., Edogawa, Tokyo, Japan
| | - Takuma Iguchi
- 1 Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., Edogawa, Tokyo, Japan
| | - Yoshimi Tsuchiya
- 2 Quantitative Clinical Pharmacology and Translational Sciences, Daiichi Sankyo, Inc., Basking Ridge, New Jersey, USA
| | - Kiyonori Kai
- 1 Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., Edogawa, Tokyo, Japan
| | - Kazuhiko Mori
- 1 Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., Edogawa, Tokyo, Japan
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111
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Nakano T, Seino K, Wakabayashi I, Stafforini DM, Topham MK, Goto K. Deletion of diacylglycerol kinase ε confers susceptibility to obesity
via
reduced lipolytic activity in murine adipocytes. FASEB J 2018; 32:4121-4131. [DOI: 10.1096/fj.201701050r] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Tomoyuki Nakano
- Department of Anatomy and Cell BiologyYamagata University School of MedicineYamagataJapan
| | - Keiko Seino
- Department of Anatomy and Cell BiologyYamagata University School of MedicineYamagataJapan
| | - Ichiro Wakabayashi
- Department of Environmental and Preventive MedicineHyogo College of MedicineNishinomiyaHyogoJapan
| | | | | | - Kaoru Goto
- Department of Anatomy and Cell BiologyYamagata University School of MedicineYamagataJapan
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112
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Samuel VT, Shulman GI. Nonalcoholic Fatty Liver Disease as a Nexus of Metabolic and Hepatic Diseases. Cell Metab 2018; 27:22-41. [PMID: 28867301 PMCID: PMC5762395 DOI: 10.1016/j.cmet.2017.08.002] [Citation(s) in RCA: 470] [Impact Index Per Article: 78.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/01/2017] [Accepted: 08/01/2017] [Indexed: 12/15/2022]
Abstract
NAFLD is closely linked with hepatic insulin resistance. Accumulation of hepatic diacylglycerol activates PKC-ε, impairing insulin receptor activation and insulin-stimulated glycogen synthesis. Peripheral insulin resistance indirectly influences hepatic glucose and lipid metabolism by increasing flux of substrates that promote lipogenesis (glucose and fatty acids) and gluconeogenesis (glycerol and fatty acid-derived acetyl-CoA, an allosteric activator of pyruvate carboxylase). Weight loss with diet or bariatric surgery effectively treats NAFLD, but drugs specifically approved for NAFLD are not available. Some new pharmacological strategies act broadly to alter energy balance or influence pathways that contribute to NAFLD (e.g., agonists for PPAR γ, PPAR α/δ, FXR and analogs for FGF-21, and GLP-1). Others specifically inhibit key enzymes involved in lipid synthesis (e.g., mitochondrial pyruvate carrier, acetyl-CoA carboxylase, stearoyl-CoA desaturase, and monoacyl- and diacyl-glycerol transferases). Finally, a novel class of liver-targeted mitochondrial uncoupling agents increases hepatocellular energy expenditure, reversing the metabolic and hepatic complications of NAFLD.
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Affiliation(s)
- Varman T Samuel
- Department of Medicine, Yale University School of Medicine, New Haven, CT 06510, USA; Veterans Affairs Medical Center, West Haven, CT 06516, USA.
| | - Gerald I Shulman
- Department of Medicine, Yale University School of Medicine, New Haven, CT 06510, USA; Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06510, USA; Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT 06510, USA.
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113
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Choi RY, Ham JR, Lee HI, Cho HW, Choi MS, Park SK, Lee J, Kim MJ, Seo KI, Lee MK. Scopoletin Supplementation Ameliorates Steatosis and Inflammation in Diabetic Mice. Phytother Res 2017; 31:1795-1804. [PMID: 28921708 DOI: 10.1002/ptr.5925] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 08/17/2017] [Accepted: 08/17/2017] [Indexed: 12/14/2022]
Abstract
Scopoletin is a bioactive component in many edible plants and fruits. This study investigated the effects of scopoletin on hepatic steatosis and inflammation in a high-fat diet fed type 1 diabetic mice by comparison with metformin. Scopoletin (0.01%, w/w) or metformin (0.5%, w/w) was provided with a high-fat diet to streptozotocin-induced diabetic mice for 11 weeks. Both scopoletin and metformin lowered blood glucose and HbA1c , serum ALT, TNF-α and IL-6 levels, glucose intolerance, and hepatic lipid accumulation compared with the diabetic control group. Scopoletin or metformin down-regulated hepatic gene expression of triglyceride (Pparg, Plpp2, and Dgat2) and cholesterol (Hmgcr) synthesis as well as inflammation (Tlr4, Myd88, Nfkb1, Tnfa, and Il6), while it up-regulated Cyp7a1 gene. Hepatic PPARγ and DGAT2 protein levels were also down-regulated in scopoletin or metformin group compared with the control group. Scopoletin or metformin also inhibited hepatic fatty acid synthase and phosphatidate phosphohydrolase activities. These results suggest that scopoletin protects against diabetes-induced steatosis and inflammation by inhibiting lipid biosynthesis and TLR4-MyD88 pathways. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- Ra-Yeong Choi
- Department of Food and Nutrition, Sunchon National University, Suncheon, 57922, Korea
| | - Ju Ri Ham
- Department of Food and Nutrition, Sunchon National University, Suncheon, 57922, Korea
| | - Hae-In Lee
- Mokpo Marin Food-Industry Research Center, Mokpo, 58621, Korea
| | - Hyun Wook Cho
- Department of Biology, Sunchon National University, Suncheon, 57922, Korea
| | - Myung-Sook Choi
- Center for Food and Nutritional Genomic Research, Kyungpook National University, Daegu, 41566, Korea.,Department of Food Science and Nutrition, Kyungpook National University, Daegu, 41566, Korea
| | - Seok-Kyu Park
- Department of Food and Nutrition, Sunchon National University, Suncheon, 57922, Korea
| | - Jin Lee
- Department of Food and Nutrition, Sunchon National University, Suncheon, 57922, Korea
| | - Myung-Joo Kim
- Department of Bakery and Barista, Suseong College, Daegu, 42078, Korea
| | - Kwon-Il Seo
- Department of Biotechnology, Dong-A University, Busan, 49315, Korea
| | - Mi-Kyung Lee
- Department of Food and Nutrition, Sunchon National University, Suncheon, 57922, Korea
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114
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Greuter T, Malhi H, Gores GJ, Shah VH. Therapeutic opportunities for alcoholic steatohepatitis and nonalcoholic steatohepatitis: exploiting similarities and differences in pathogenesis. JCI Insight 2017; 2:95354. [PMID: 28878132 DOI: 10.1172/jci.insight.95354] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Alcoholic steatohepatitis (ASH) and nonalcoholic steatohepatitis (NASH) are among the most frequent causes of chronic liver disease in the United States. Although the two entities are triggered by different etiologies - chronic alcohol consumption (ASH) and obesity-associated lipotoxicity (NASH) - they share overlapping histological and clinical features owing to common pathogenic mechanisms. These pathogenic processes include altered hepatocyte lipid metabolism, organelle dysfunction (i.e., ER stress), hepatocyte apoptosis, innate immune system activation, and hepatic stellate cell activation. Nonetheless, there are several disease-specific molecular signaling pathways, such as differential pathway activation downstream of TLR4 (MyD88-dependence in NASH versus MyD88-independence in ASH), inflammasome activation and IL-1β signaling in ASH, insulin resistance and lipotoxicity in NASH, and dysregulation of different microRNAs, which clearly highlight that ASH and NASH are two distinct biological entities. Both pathogenic similarities and differences have therapeutic implications. In this Review, we discuss these pathogenic mechanisms and their therapeutic implications for each disease, focusing on both shared and distinct targets.
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Affiliation(s)
- Thomas Greuter
- Division of Gastroenterology and Hepatology, University Hospital Zurich, Zurich, Switzerland.,Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota, USA
| | - Harmeet Malhi
- Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota, USA
| | - Gregory J Gores
- Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota, USA
| | - Vijay H Shah
- Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota, USA
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115
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Wallstab C, Eleftheriadou D, Schulz T, Damm G, Seehofer D, Borlak J, Holzhütter HG, Berndt N. A unifying mathematical model of lipid droplet metabolism reveals key molecular players in the development of hepatic steatosis. FEBS J 2017; 284:3245-3261. [PMID: 28763157 DOI: 10.1111/febs.14189] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 06/02/2017] [Accepted: 07/28/2017] [Indexed: 12/16/2022]
Abstract
The liver responds to elevated plasma concentrations of free fatty acids (FFAs) with an enhanced uptake of FFAs and their esterification to triacylglycerol (TAG). On the long term, this may result in massive hepatic TAG accumulation called steatosis hepatitis. In hepatocytes, the poor water-soluble TAG is packed in specialized organelles: Lipid droplets (LDs) serving as transient cellular deposit and lipoproteins (LPs) transporting TAG and cholesterol esters to extra-hepatic tissues. The dynamics of these organelles is controlled by a variety of regulatory surface proteins (RSPs). Assembly and export of VLDLs are mainly regulated by the microsomal transfer protein (MTP) and apoprotein B100. Formation and lipolysis of LDs are regulated by several RSPs. The best studied regulators belong to the PAT (Perilipin/Adipophilin/TIP47) and CIDE families. Knockdown or overexpression of SRPs may significantly affect the total number and size distribution of LDs. Intriguingly, a large cell-to-cell heterogeneity with respect to the number and size of LDs has been found in various cell types including hepatocytes. These findings suggest that the extent of cellular lipid accumulation is determined not only by the imbalance between lipid supply and utilization but also by variations in the expression of RSPs and metabolic enzymes. To better understand the relative regulatory impact of individual processes involved in the cellular TAG turnover, we developed a comprehensive kinetic model encompassing the pathways of the fatty acid and triglyceride metabolism and the main molecular processes governing the dynamics of LDs. The model was parametrized such that a large number of experimental in vitro and in vivo findings are correctly recapitulated. A control analysis of the model revealed that variations in the activity of FFA uptake, diacylglycerol acyltransferase (DGAT) 2, and adipose triglyceride lipase (ATGL) have the strongest influence on the cellular TAG level. We used the model to simulate LD size distributions in human hepatoma cells and hepatocytes exposed to a challenge with FFAs. A random fold change by a factor of about two in the activity of RSPs was sufficient to reproduce the large diversity of droplet size distributions observed in individual cells. Under the premise that the same extent of variability of RSPs holds for the intact organ, our model predicts variations in the TAG content of individual hepatocytes by a factor of about 3-6 depending on the nutritional regime. Taken together, our modeling approach integrates numerous experimental findings on individual processes in the cellular TAG metabolism and LD dynamics metabolism to a consistent state-of-the-art dynamic network model that can be used to study how changes in the external conditions or systemic parameters will affect the TAG content of hepatocytes.
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Affiliation(s)
- Christin Wallstab
- Institute of Biochemistry, Computational Systems Biochemistry Group, Charite - University Medicine Berlin, Germany
| | - Dimitra Eleftheriadou
- Institute of Biochemistry, Computational Systems Biochemistry Group, Charite - University Medicine Berlin, Germany
| | - Theresa Schulz
- Clinic for General-, Visceral- and Transplantation Surgery, Charite - University Medicine Berlin, Germany
| | - Georg Damm
- Clinic for General-, Visceral- and Transplantation Surgery, Charite - University Medicine Berlin, Germany.,Department of Hepatobiliary Surgery and Visceral Transplantation, University of Leipzig, Germany
| | - Daniel Seehofer
- Clinic for General-, Visceral- and Transplantation Surgery, Charite - University Medicine Berlin, Germany.,Department of Hepatobiliary Surgery and Visceral Transplantation, University of Leipzig, Germany
| | - Jürgen Borlak
- Centre for Pharmacology and Toxicology, Institute for Pharmaco- and Toxicogenomics, Hannover Medical School, Hannover, Germany
| | - Hermann-Georg Holzhütter
- Institute of Biochemistry, Computational Systems Biochemistry Group, Charite - University Medicine Berlin, Germany
| | - Nikolaus Berndt
- Institute of Biochemistry, Computational Systems Biochemistry Group, Charite - University Medicine Berlin, Germany
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116
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Wang C, Batey R, Yamahara J, Li Y. Multiple molecular targets in the liver, adipose tissue and skeletal muscle in ginger-elicited amelioration of nonalcoholic fatty liver disease. J Funct Foods 2017. [DOI: 10.1016/j.jff.2017.06.040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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117
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Abstract
Hepatic steatosis is an underlying feature of nonalcoholic fatty liver disease (NAFLD), which is the most common form of liver disease and is present in up to ∼70% of individuals who are overweight. NAFLD is also associated with hypertriglyceridaemia and low levels of HDL, glucose intolerance, insulin resistance and type 2 diabetes mellitus. Hepatic steatosis is a strong predictor of the development of insulin resistance and often precedes the onset of other known mediators of insulin resistance. This sequence of events suggests that hepatic steatosis has a causal role in the development of insulin resistance in other tissues, such as skeletal muscle. Hepatokines are proteins that are secreted by hepatocytes, and many hepatokines have been linked to the induction of metabolic dysfunction, including fetuin A, fetuin B, retinol-binding protein 4 (RBP4) and selenoprotein P. In this Review, we describe the factors that influence the development of hepatic steatosis, provide evidence of strong links between hepatic steatosis and insulin resistance in non-hepatic tissues, and discuss recent advances in our understanding of how steatosis alters hepatokine secretion to influence metabolic phenotypes through inter-organ communication.
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Affiliation(s)
- Ruth C R Meex
- Monash Biomedicine Discovery Institute, Metabolic Disease and Obesity Program and the Department of Physiology, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
- Department of Human Biology, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, Universiteitssingel 50, 6229 ER Maastricht, The Netherlands
| | - Matthew J Watt
- Monash Biomedicine Discovery Institute, Metabolic Disease and Obesity Program and the Department of Physiology, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
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118
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Qiang J, Bao WJ, Tao FY, He J, Li XH, Xu P, Sun LY. The expression profiles of miRNA-mRNA of early response in genetically improved farmed tilapia (Oreochromis niloticus) liver by acute heat stress. Sci Rep 2017; 7:8705. [PMID: 28821885 PMCID: PMC5562739 DOI: 10.1038/s41598-017-09264-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 07/17/2017] [Indexed: 12/16/2022] Open
Abstract
Genetically improved farmed tilapia (GIFT, Oreochromis niloticus) are commercially important fish that are cultured in China. GIFT are highly susceptible to diseases when exposed to high temperatures in summer. Better understanding the GIFT regulatory response to heat stress will not only help in determining the relationship between heat stress signalling pathways and adaption mechanisms, but will also contribute to breeding new high-temperature tolerant strains of GIFT. In this study, we built control (28 °C) and heat-treated (37.5 °C) groups, and extracted RNA from the liver tissues for high-throughput next-generation sequencing to study the miRNA and mRNA expression profiles. We identified 28 differentially expressed (DE) miRNAs and 744 DE mRNAs between the control and heat-treated groups and annotated them using the KEGG database. A total of 38 target genes were predicted for 21 of the DE miRNAs, including 64 negative miRNA-mRNA interactions. We verified 15 DE miRNA-mRNA pairs and 16 other DE mRNAs by quantitative real-time PCR. Important regulatory pathways involved in the early response of GIFT to heat stress included organism system, metabolism, and diseases. Our findings will facilitate the understanding of regulatory pathways affected by acute heat stress, which will help to better prevent heat damage to GIFT.
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Affiliation(s)
- Jun Qiang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Centre, Chinese Academy of Fishery Sciences, 9 Shanshui East Road, Wuxi, Jiangsu, 214081, China
| | - Wen J Bao
- Wuxi Fisheries College, Nanjing Agricultural University, 9 Shanshui East Road, Wuxi, Jiangsu, 214081, China
| | - Fan Y Tao
- Wuxi Fisheries College, Nanjing Agricultural University, 9 Shanshui East Road, Wuxi, Jiangsu, 214081, China
| | - Jie He
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Centre, Chinese Academy of Fishery Sciences, 9 Shanshui East Road, Wuxi, Jiangsu, 214081, China
| | - Xia H Li
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Centre, Chinese Academy of Fishery Sciences, 9 Shanshui East Road, Wuxi, Jiangsu, 214081, China
| | - Pao Xu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Centre, Chinese Academy of Fishery Sciences, 9 Shanshui East Road, Wuxi, Jiangsu, 214081, China.
| | - Lan Y Sun
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Centre, Chinese Academy of Fishery Sciences, 9 Shanshui East Road, Wuxi, Jiangsu, 214081, China
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119
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Pre- and post-prandial expression of genes involved in lipid metabolism at the end of the overfeeding period of mule ducks. Mol Cell Biochem 2017; 438:111-121. [DOI: 10.1007/s11010-017-3118-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 07/15/2017] [Indexed: 01/23/2023]
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120
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Abstract
Non-alcoholic fatty liver disease (NAFLD) is the most common form of liver disease and leading cause of cirrhosis in the United States and developed countries. NAFLD is closely associated with obesity, insulin resistance and metabolic syndrome, significantly contributing to the exacerbation of the latter. Although NAFLD represents the hepatic component of metabolic syndrome, it can also be found in patients prior to their presentation with other manifestations of the syndrome. The pathogenesis of NAFLD is complex and closely intertwined with insulin resistance and obesity. Several mechanisms are undoubtedly involved in its pathogenesis and progression. In this review, we bring together the current understanding of the pathogenesis that makes NAFLD a systemic disease.
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Affiliation(s)
- Isabella Reccia
- Department of Surgery and Cancer Faculty of Medicine, Hammersmith Hospital, Imperial College London, UK.
| | - Jayant Kumar
- Department of Surgery and Cancer Faculty of Medicine, Hammersmith Hospital, Imperial College London, UK.
| | - Cherif Akladios
- Department of Surgery and Cancer Faculty of Medicine, Hammersmith Hospital, Imperial College London, UK.
| | - Francesco Virdis
- Department of Surgery and Cancer Faculty of Medicine, Hammersmith Hospital, Imperial College London, UK.
| | - Madhava Pai
- Department of Surgery and Cancer Faculty of Medicine, Hammersmith Hospital, Imperial College London, UK.
| | - Nagy Habib
- Department of Surgery and Cancer Faculty of Medicine, Hammersmith Hospital, Imperial College London, UK.
| | - Duncan Spalding
- Department of Surgery and Cancer Faculty of Medicine, Hammersmith Hospital, Imperial College London, UK.
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121
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Engin A. Non-Alcoholic Fatty Liver Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 960:443-467. [DOI: 10.1007/978-3-319-48382-5_19] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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122
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Hung YH, Carreiro AL, Buhman KK. Dgat1 and Dgat2 regulate enterocyte triacylglycerol distribution and alter proteins associated with cytoplasmic lipid droplets in response to dietary fat. Biochim Biophys Acta Mol Cell Biol Lipids 2017; 1862:600-614. [PMID: 28249764 PMCID: PMC5503214 DOI: 10.1016/j.bbalip.2017.02.014] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 01/31/2017] [Accepted: 02/24/2017] [Indexed: 12/16/2022]
Abstract
Enterocytes, the absorptive cells of the small intestine, mediate efficient absorption of dietary fat (triacylglycerol, TAG). The digestive products of dietary fat are taken up by enterocytes, re-esterified into TAG, and packaged on chylomicrons (CMs) for secretion into blood or temporarily stored within cytoplasmic lipid droplets (CLDs). Altered enterocyte TAG distribution impacts susceptibility to high fat diet associated diseases, but molecular mechanisms directing TAG toward these fates are unclear. Two enzymes, acyl CoA: diacylglycerol acyltransferase 1 (Dgat1) and Dgat2, catalyze the final, committed step of TAG synthesis within enterocytes. Mice with intestine-specific overexpression of Dgat1 (Dgat1Int) or Dgat2 (Dgat2Int), or lack of Dgat1 (Dgat1-/-), were previously found to have altered intestinal TAG secretion and storage. We hypothesized that varying intestinal Dgat1 and Dgat2 levels alters TAG distribution in subcellular pools for CM synthesis as well as the morphology and proteome of CLDs. To test this we used ultrastructural and proteomic methods to investigate intracellular TAG distribution and CLD-associated proteins in enterocytes from Dgat1Int, Dgat2Int, and Dgat1-/- mice 2h after a 200μl oral olive oil gavage. We found that varying levels of intestinal Dgat1 and Dgat2 altered TAG pools involved in CM assembly and secretion, the number or size of CLDs present in enterocytes, and the enterocyte CLD proteome. Overall, these results support a model where Dgat1 and Dgat2 function coordinately to regulate the process of dietary fat absorption by preferentially synthesizing TAG for incorporation into distinct subcellular TAG pools in enterocytes.
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Affiliation(s)
- Yu-Han Hung
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907, USA
| | - Alicia L Carreiro
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907, USA
| | - Kimberly K Buhman
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907, USA.
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123
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Miotto PM, Horbatuk M, Proudfoot R, Matravadia S, Bakovic M, Chabowski A, Holloway GP. α-Linolenic acid supplementation and exercise training reveal independent and additive responses on hepatic lipid accumulation in obese rats. Am J Physiol Endocrinol Metab 2017; 312:E461-E470. [PMID: 28270444 PMCID: PMC5494579 DOI: 10.1152/ajpendo.00438.2016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 03/02/2017] [Accepted: 03/03/2017] [Indexed: 02/06/2023]
Abstract
α-Linolenic acid (ALA) supplementation or exercise training can independently prevent hepatic lipid accumulation and reduced insulin signaling; however, this may occur through different mechanisms of action. In the current study, obese Zucker rats displayed decreased phospholipid (PL) content in association with hepatic lipid abundance, and therefore, we examined whether ALA and exercise training would prevent these abnormalities differently to reveal additive effects on the liver. To achieve this aim, obese Zucker rats were fed control diet alone or supplemented with ALA and were sedentary or exercise trained for 4 wk (C-Sed, ALA-Sed, C-Ex, and ALA-Ex). ALA-Sed rats had increased microsomal-triglyceride transfer protein (MTTP), a protein required for lipoprotein assembly/secretion, as well as modestly increased PL content in the absence of improvements in mitochondrial content, lipid accumulation, or insulin sensitivity. In contrast, C-Ex rats had increased mitochondrial content and insulin sensitivity; however, this corresponded with minimal improvements in PL content and hepatic lipid accumulation. Importantly, ALA-Ex rats demonstrated additive improvements in PL content and hepatic steatosis, which corresponded with increased mitochondrial content, MTTP and apolipoprotein B100 content, greater serum triacylglyceride, and insulin sensitivity. Overall, these data demonstrate additive effects of ALA and exercise training on hepatic lipid accumulation, as exercise training preferentially increased mitochondrial content, while ALA promoted an environment conducive for lipid secretion. These data highlight the potential for combination therapy to mitigate liver disease progression.
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Affiliation(s)
- Paula M Miotto
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada; and
| | - Meaghan Horbatuk
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada; and
| | - Ross Proudfoot
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada; and
| | - Sarthak Matravadia
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada; and
| | - Marica Bakovic
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada; and
| | - Adrian Chabowski
- Department of Physiology, Medical University of Bialystok, Bialystok, Poland
| | - Graham P Holloway
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada; and
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124
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Bai X, Hong W, Cai P, Chen Y, Xu C, Cao D, Yu W, Zhao Z, Huang M, Jin J. Valproate induced hepatic steatosis by enhanced fatty acid uptake and triglyceride synthesis. Toxicol Appl Pharmacol 2017; 324:12-25. [PMID: 28366540 DOI: 10.1016/j.taap.2017.03.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 03/06/2017] [Accepted: 03/28/2017] [Indexed: 02/07/2023]
Abstract
Steatosis is the characteristic type of VPA-induced hepatotoxicity and may result in life-threatening hepatic lesion. Approximately 61% of patients treated with VPA have been diagnosed with hepatic steatosis through ultrasound examination. However, the mechanisms underlying VPA-induced intracellular fat accumulation are not yet fully understood. Here we demonstrated the involvement of fatty acid uptake and lipogenesis in VPA-induced hepatic steatosis in vitro and in vivo by using quantitative real-time PCR (qRT-PCR) analysis, western blotting analysis, fatty acid uptake assays, Nile Red staining assays, and Oil Red O staining assays. Specifically, we found that the expression of cluster of differentiation 36 (CD36), an important fatty acid transport, and diacylglycerol acyltransferase 2 (DGAT2) were significantly up-regulated in HepG2 cells and livers of C57B/6J mice after treatment with VPA. Furthermore, VPA treatment remarkably enhanced the efficiency of fatty acid uptake mediated by CD36, while this effect was abolished by the interference with CD36-specific siRNA. Also, VPA treatment significantly increased DGAT2 expression as a result of the inhibition of mitogen-activated protein kinase kinase (MEK) - extracellular regulated kinase (ERK) pathway; however, DGAT2 knockdown significantly alleviated VPA-induced intracellular lipid accumulation. Additionally, we also found that sterol regulatory element binding protein-1c (SREBP-1c)-mediated fatty acid synthesis may be not involved in VPA-induced hepatic steatosis. Overall, VPA-triggered over-regulation of CD36 and DGAT2 could be helpful for a better understanding of the mechanisms underlying VPA-induced hepatic steatosis and may offer novel therapeutic strategies to combat VPA-induced hepatotoxicity.
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Affiliation(s)
- Xupeng Bai
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Weipeng Hong
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Peiheng Cai
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Yibei Chen
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Chuncao Xu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Di Cao
- School of Chinese Materia Medica, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Weibang Yu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Zhongxiang Zhao
- School of Chinese Materia Medica, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Min Huang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Jing Jin
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China.
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125
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Krishnan A, Abdullah TS, Mounajjed T, Hartono S, McConico A, White T, LeBrasseur N, Lanza I, Nair S, Gores G, Charlton M. A longitudinal study of whole body, tissue, and cellular physiology in a mouse model of fibrosing NASH with high fidelity to the human condition. Am J Physiol Gastrointest Liver Physiol 2017; 312:G666-G680. [PMID: 28232454 PMCID: PMC6146305 DOI: 10.1152/ajpgi.00213.2016] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 02/14/2017] [Accepted: 02/14/2017] [Indexed: 01/31/2023]
Abstract
The sequence of events that lead to inflammation and fibrosing nonalcoholic steatohepatitis (NASH) is incompletely understood. Hence, we investigated the chronology of whole body, tissue, and cellular events that occur during the evolution of diet-induced NASH. Male C57Bl/6 mice were assigned to a fast-food (FF; high calorie, high cholesterol, high fructose) or standard-chow (SC) diet over a period of 36 wk. Liver histology, body composition, mitochondrial respiration, metabolic rate, gene expression, and hepatic lipid content were analyzed. Insulin resistance [homeostasis model assessment-insulin resistance (HOMA-IR)] increased 10-fold after 4 wk. Fibrosing NASH was fully established by 16 wk. Total hepatic lipids increased by 4 wk and remained two- to threefold increased throughout. Hepatic triglycerides declined from sixfold increase at 8 wk to threefold increase by 36 wk. In contrast, hepatic cholesterol levels steadily increased from baseline at 8 wk to twofold by 36 wk. The hepatic immune cell population altered over time with macrophages persisting beyond 16 wk. Mitochondrial oxygen flux rates of FF mice diet were uniformly lower with all the tested substrates (13-276 pmol·s-1·ml-1 per unit citrate synthase) than SC mice (17-394 pmol·s-1·ml-1 per unit citrate synthase) and was accompanied by decreased mitochondrial:nuclear gene copy number ratios after 4 wk. Metabolic rate was lower in FF mice. Mitochondrial glutathione was significantly decreased at 24 wk in FF mice. Expression of dismutases and catalase was also decreased in FF mice. The evolution of NASH in the FF diet-induced model is multiphasic, particularly in terms of hepatic lipid composition. Insulin resistance precedes hepatic inflammation and fibrosis. Mitochondrial dysfunction and depletion occur after the histological features of NASH are apparent. Collectively, these observations provide a unique overview of the sequence of changes that coevolve with the histological evolution of NASH.NEW & NOTEWORTHY This study demonstrates in a first of kind longitudinal analysis, the evolution of nonalcoholic steatohepatitis (NASH) on a fast-food diet-induced model. Key findings include 1) hepatic lipid composition changes in a multiphasic fashion as NASH evolves; 2) insulin resistance precedes hepatic inflammation and fibrosis, answering a longstanding chicken-and-egg question regarding the relationship of insulin resistance to liver histology in NASH; and 3) mitochondrial dysfunction and depletion occur after the histological features of NASH are apparent.
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Affiliation(s)
| | - Tasduq Sheikh Abdullah
- 2Indian Institute of Integrative Medicine, Council of Scientific and Industrial Research, Jammu and Kashmir, India;
| | - Taofic Mounajjed
- 3Division of Anatomic Pathology, Mayo Clinic, Rochester, Minnesota;
| | - Stella Hartono
- 4Division of Immunology, Mayo Clinic, Rochester, Minnesota;
| | - Andrea McConico
- 5Division of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota;
| | - Thomas White
- 6Robert and Arlene Kogod Centre for Aging, Mayo Clinic, Rochester, Minnesota;
| | - Nathan LeBrasseur
- 6Robert and Arlene Kogod Centre for Aging, Mayo Clinic, Rochester, Minnesota;
| | - Ian Lanza
- 7Division of Endocrinology, Mayo Clinic, Rochester, Minnesota; and
| | - Sreekumaran Nair
- 7Division of Endocrinology, Mayo Clinic, Rochester, Minnesota; and
| | - Gregory Gores
- 1Division of Gastroenterology, Mayo Clinic, Rochester, Minnesota;
| | - Michael Charlton
- Division of Gastroenterology, Mayo Clinic, Rochester, Minnesota; .,Division of Hepatology, Intermountain Healthcare, Salt Lake City, Utah
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126
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Petersen MC, Shulman GI. Roles of Diacylglycerols and Ceramides in Hepatic Insulin Resistance. Trends Pharmacol Sci 2017; 38:649-665. [PMID: 28551355 DOI: 10.1016/j.tips.2017.04.004] [Citation(s) in RCA: 245] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 04/19/2017] [Accepted: 04/20/2017] [Indexed: 12/22/2022]
Abstract
Although ample evidence links hepatic lipid accumulation with hepatic insulin resistance, the mechanistic basis of this association is incompletely understood and controversial. Diacylglycerols (DAGs) and ceramides have emerged as the two best-studied putative mediators of lipid-induced hepatic insulin resistance. Both lipids were first associated with insulin resistance in skeletal muscle and were subsequently hypothesized to mediate insulin resistance in the liver. However, the putative roles for DAGs and ceramides in hepatic insulin resistance have proved more complex than originally imagined, with various genetic and pharmacologic manipulations yielding a vast and occasionally contradictory trove of data to sort. In this review we examine the state of this field, turning a critical eye toward both DAGs and ceramides as putative mediators of lipid-induced hepatic insulin resistance.
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Affiliation(s)
- Max C Petersen
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Gerald I Shulman
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06520, USA; Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT 06520, USA.
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127
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Oxidative stress and calcium dysregulation by palmitate in type 2 diabetes. Exp Mol Med 2017; 49:e291. [PMID: 28154371 PMCID: PMC5336562 DOI: 10.1038/emm.2016.157] [Citation(s) in RCA: 221] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 10/07/2016] [Accepted: 10/16/2016] [Indexed: 12/12/2022] Open
Abstract
Free fatty acids (FFAs) are important substrates for mitochondrial oxidative metabolism and ATP synthesis but also cause serious stress to various tissues, contributing to the development of metabolic diseases. CD36 is a major mediator of cellular FFA uptake. Inside the cell, saturated FFAs are able to induce the production of cytosolic and mitochondrial reactive oxygen species (ROS), which can be prevented by co-exposure to unsaturated FFAs. There are close connections between oxidative stress and organellar Ca2+ homeostasis. Highly oxidative conditions induced by palmitate trigger aberrant endoplasmic reticulum (ER) Ca2+ release and thereby deplete ER Ca2+ stores. The resulting ER Ca2+ deficiency impairs chaperones of the protein folding machinery, leading to the accumulation of misfolded proteins. This ER stress may further aggravate oxidative stress by augmenting ER ROS production. Secondary to ER Ca2+ release, cytosolic and mitochondrial matrix Ca2+ concentrations can also be altered. In addition, plasmalemmal ion channels operated by ER Ca2+ depletion mediate persistent Ca2+ influx, further impairing cytosolic and mitochondrial Ca2+ homeostasis. Mitochondrial Ca2+ overload causes superoxide production and functional impairment, culminating in apoptosis. This vicious cycle of lipotoxicity occurs in multiple tissues, resulting in β-cell failure and insulin resistance in target tissues, and further aggravates diabetic complications.
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128
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Erion DM, Park HJ, Lee HY. The role of lipids in the pathogenesis and treatment of type 2 diabetes and associated co-morbidities. BMB Rep 2017; 49:139-48. [PMID: 26728273 PMCID: PMC4915228 DOI: 10.5483/bmbrep.2016.49.3.268] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2016] [Indexed: 12/25/2022] Open
Abstract
In the past decade, the incidence of type 2 diabetes (T2D) has rapidly increased, along with the associated cardiovascular complications. Therefore, understanding the pathophysiology underlying T2D, the associated complications and the impact of therapeutics on the T2D development has critical importance for current and future therapeutics. The prevailing feature of T2D is hyperglycemia due to excessive hepatic glucose production, insulin resistance, and insufficient secretion of insulin by the pancreas. These contribute to increased fatty acid influx into the liver and muscle causing accumulation of lipid metabolites. These lipid metabolites cause dyslipidemia and non-alcoholic fatty liver disease, which ultimately contributes to the increased cardiovascular risk in T2D. Therefore, understanding the mechanisms of hepatic insulin resistance and the specific role of liver lipids is critical in selecting and designing the most effective therapeutics for T2D and the associated co-morbidities, including dyslipidemia and cardiovascular disease. Herein, we review the effects and molecular mechanisms of conventional anti-hyperglycemic and lipid-lowering drugs on glucose and lipid metabolism. [BMB Reports 2016; 49(3): 139-148].
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Affiliation(s)
- Derek M Erion
- Takeda Pharmaceuticals 350 Massachusetts Ave. Cambridge, MA, 02139, USA
| | - Hyun-Jun Park
- Department of Molecular Medicine, Lee Gil Ya Cancer and Diabetes Institute, School of Medicine, Gachon University, Incheon 21999, Korea
| | - Hui-Young Lee
- Department of Molecular Medicine and Korea Mouse Metabolic Phenotyping Center, Lee Gil Ya Cancer and Diabetes Institute, School of Medicine, Gachon University, Incheon 21999, Korea
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Futatsugi K, Huard K, Kung DW, Pettersen JC, Flynn DA, Gosset JR, Aspnes GE, Barnes RJ, Cabral S, Dowling MS, Fernando DP, Goosen TC, Gorczyca WP, Hepworth D, Herr M, Lavergne S, Li Q, Niosi M, Orr STM, Pardo ID, Perez SM, Purkal J, Schmahai TJ, Shirai N, Shoieb AM, Zhou J, Goodwin B. Small structural changes of the imidazopyridine diacylglycerol acyltransferase 2 (DGAT2) inhibitors produce an improved safety profile. MEDCHEMCOMM 2016; 8:771-779. [PMID: 30108796 DOI: 10.1039/c6md00564k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 11/08/2016] [Indexed: 11/21/2022]
Abstract
Small molecule DGAT2 inhibitors have shown promise for the treatment of metabolic diseases in preclinical models. Herein, we report the first toxicological evaluation of imidazopyridine-based DGAT2 inhibitors and show that the arteriopathy associated with imidazopyridine 1 can be mitigated with small structural modifications, and is thus not mechanism related.
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Affiliation(s)
- K Futatsugi
- Pfizer Inc. Medicine Design , 610 Main Street , Cambridge , Massachusetts , 02155 USA .
| | - K Huard
- Pfizer Inc. Medicine Design , 610 Main Street , Cambridge , Massachusetts , 02155 USA .
| | - D W Kung
- Pfizer Inc. Medicine Design , Eastern Point Road , Groton , Connecticut , 06340 USA .
| | - J C Pettersen
- Pfizer Inc. Drug Safety Research and Development , Eastern Point Road , Groton , Connecticut , 06340 USA
| | - D A Flynn
- Pfizer Inc. Drug Safety Research and Development , Eastern Point Road , Groton , Connecticut , 06340 USA
| | - J R Gosset
- Pfizer Inc. Medicine Design , 610 Main Street , Cambridge , Massachusetts , 02155 USA .
| | - G E Aspnes
- Pfizer Inc. Medicine Design , 610 Main Street , Cambridge , Massachusetts , 02155 USA .
| | - R J Barnes
- Pfizer Inc. Drug Safety Research and Development , Eastern Point Road , Groton , Connecticut , 06340 USA
| | - S Cabral
- Pfizer Inc. Medicine Design , Eastern Point Road , Groton , Connecticut , 06340 USA .
| | - M S Dowling
- Pfizer Inc. Medicine Design , Eastern Point Road , Groton , Connecticut , 06340 USA .
| | - D P Fernando
- Pfizer Inc. Medicine Design , Eastern Point Road , Groton , Connecticut , 06340 USA .
| | - T C Goosen
- Pfizer Inc. Medicine Design , Eastern Point Road , Groton , Connecticut , 06340 USA .
| | - W P Gorczyca
- Pfizer Inc. Drug Safety Research and Development , Eastern Point Road , Groton , Connecticut , 06340 USA
| | - D Hepworth
- Pfizer Inc. Medicine Design , 610 Main Street , Cambridge , Massachusetts , 02155 USA .
| | - M Herr
- Pfizer Inc. Medicine Design , Eastern Point Road , Groton , Connecticut , 06340 USA .
| | - S Lavergne
- Pfizer Inc. Medicine Design , Eastern Point Road , Groton , Connecticut , 06340 USA .
| | - Q Li
- Pfizer Inc. Medicine Design , Eastern Point Road , Groton , Connecticut , 06340 USA .
| | - M Niosi
- Pfizer Inc. Medicine Design , Eastern Point Road , Groton , Connecticut , 06340 USA .
| | - S T M Orr
- Pfizer Inc. Medicine Design , Eastern Point Road , Groton , Connecticut , 06340 USA .
| | - I D Pardo
- Pfizer Inc. Drug Safety Research and Development , Eastern Point Road , Groton , Connecticut , 06340 USA
| | - S M Perez
- Pfizer Inc. Cardiovascular and Metabolic Disease Research Unit , 610 Main Street , Cambridge , Massachusetts , 02155 USA
| | - J Purkal
- Pfizer Inc. Cardiovascular and Metabolic Disease Research Unit , 610 Main Street , Cambridge , Massachusetts , 02155 USA
| | - T J Schmahai
- Pfizer Inc. Drug Safety Research and Development , Eastern Point Road , Groton , Connecticut , 06340 USA
| | - N Shirai
- Pfizer Inc. Drug Safety Research and Development , Eastern Point Road , Groton , Connecticut , 06340 USA
| | - A M Shoieb
- Pfizer Inc. Drug Safety Research and Development , Eastern Point Road , Groton , Connecticut , 06340 USA
| | - J Zhou
- Pfizer Inc. Drug Safety Research and Development , Eastern Point Road , Groton , Connecticut , 06340 USA
| | - B Goodwin
- Pfizer Inc. Cardiovascular and Metabolic Disease Research Unit , 610 Main Street , Cambridge , Massachusetts , 02155 USA
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Tavernier A, Davail S, Ricaud K, Bernadet MD, Gontier K. Genes involved in the establishment of hepatic steatosis in Muscovy, Pekin and mule ducks. Mol Cell Biochem 2016; 424:147-161. [DOI: 10.1007/s11010-016-2850-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 10/14/2016] [Indexed: 10/20/2022]
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131
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Mohan V, Das S, Rao SBS. Hydroxytyrosol, a dietary phenolic compound forestalls the toxic effects of methylmercury-induced toxicity in IMR-32 human neuroblastoma cells. ENVIRONMENTAL TOXICOLOGY 2016; 31:1264-1275. [PMID: 25736103 DOI: 10.1002/tox.22134] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 02/09/2015] [Accepted: 02/15/2015] [Indexed: 06/04/2023]
Abstract
This study demonstrates the protective potential of hydroxytyrosol (HT), an olive oil phenol, against methylmercury (MeHg)-induced neurotoxicity using IMR-32 human neuroblastoma cell line. HT inhibited MeHg-induced cytotoxicity and genotoxicity as confirmed by MTT, micronucleus, and comet assays. Cells preconditioned with HT showed reduction of MeHg-induced cellular oxidative stress along with the maintenance of glutathione, superoxide dismutase, glutathione-S-tranferase, and catalase. Fluorescence microscopy and DNA ladder assays indicated the inhibitory effect of HT against MeHg-induced apoptosis, which was further established by Western blotting. An effective concentration of 5 µM HT caused downregulation of p53, bax, cytochrome c, and caspase 3 and upregulation of prosurvival proteins including nuclear factor erythroid 2-related factor 2 (Nrf2) and metallothionein. This work indicates the cytoprotective potential of HT against MeHg-induced toxicity primarily by the lowering of oxidative stress, which may be endorsed to its antigenotoxic and antiapoptotic potential, in addition to its free radical scavenging ability. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1264-1275, 2016.
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Affiliation(s)
- Vishnu Mohan
- Department of Biotechnology, School of Life Sciences, Manipal University, Manipal, 576 104, Karnataka, India
| | - Shubhankar Das
- Department of Radiation Biology and Toxicology, School of Life Sciences, Manipal University, Manipal, 576 104, Karnataka, India
| | - Satish B S Rao
- Department of Radiation Biology and Toxicology, School of Life Sciences, Manipal University, Manipal, 576 104, Karnataka, India
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Liu L, Wang S, Yao L, Li JX, Ma P, Jiang LR, Ke DZ, Pan YQ, Wang JW. Long-term fructose consumption prolongs hepatic stearoyl-CoA desaturase 1 activity independent of upstream regulation in rats. Biochem Biophys Res Commun 2016; 479:643-648. [PMID: 27697525 DOI: 10.1016/j.bbrc.2016.09.160] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Accepted: 09/29/2016] [Indexed: 02/08/2023]
Abstract
Dietary fructose is considered a risk factor for metabolic disorders, such as fatty liver disease. However, the mechanism underlying the effects of fructose is not well characterized. We investigated the hepatic expression of key regulatory genes related to lipid metabolism following fructose feeding under well-defined conditions. Rats were fed standard chow supplemented with 10% w/v fructose solution for 5 weeks, and killed after chow-fasting and fructose withdrawal (fasting) or chow-fasting and continued fructose (fructose alone) for 14 h. Hepatic deposition of triglycerides was found in rats from both groups. As expected, fructose alone increased mRNA levels of lipogenesis-related genes and correspondingly decreased mRNA levels of lipid oxidative genes in the liver. Interesting, hepatic levels of stearoyl-CoA desaturase (SCD)1 mRNA remained elevated under fructose withdrawn conditions, although expression levels of other genes, including two key transcription factors (carbohydrate response element binding protein (ChREBP) and sterol regulatory element-binding protein (SREBP)-1c) fell to normal levels, indicating that long-term fructose intake increased SCD1 activity, independent of upstream regulatory genes, such as ChREBP and SREBP-1c. In conclusion, SCD1 overexpression in fatty liver disease is not affected by fasting after long-term fructose consumption in rats. Regulation of SCD1 plays an important role in fructose-induced hepatic steatosis.
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Affiliation(s)
- Li Liu
- Faculty of Basic Medical Sciences, Chongqing Medical University, Chongqing 400016 China
| | - Shang Wang
- Faculty of Basic Medical Sciences, Chongqing Medical University, Chongqing 400016 China
| | - Ling Yao
- The Laboratory of Traditional Chinese Medicine, Chongqing Medical University, 400016 China
| | - Jin-Xiu Li
- The Laboratory of Traditional Chinese Medicine, Chongqing Medical University, 400016 China
| | - Peng Ma
- Faculty of Basic Medical Sciences, Chongqing Medical University, Chongqing 400016 China
| | - Li-Rong Jiang
- Faculty of Basic Medical Sciences, Chongqing Medical University, Chongqing 400016 China
| | - Da-Zhi Ke
- The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010 China
| | - Yong-Quan Pan
- The Laboratory Animal Center, Chongqing Medical University, Chongqing 400016 China
| | - Jian-Wei Wang
- The Laboratory of Traditional Chinese Medicine, Chongqing Medical University, 400016 China.
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Fomenko EV, Chi Y. Mangiferin modulation of metabolism and metabolic syndrome. Biofactors 2016; 42:492-503. [PMID: 27534809 PMCID: PMC5077701 DOI: 10.1002/biof.1309] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 05/21/2016] [Accepted: 06/05/2016] [Indexed: 12/17/2022]
Abstract
The recent emergence of a worldwide epidemic of metabolic disorders, such as obesity and diabetes, demands effective strategy to develop nutraceuticals or pharmaceuticals to halt this trend. Natural products have long been and continue to be an attractive source of nutritional and pharmacological therapeutics. One such natural product is mangiferin (MGF), the predominant constituent of extracts of the mango plant Mangifera indica L. Reports on biological and pharmacological effects of MGF increased exponentially in recent years. MGF has documented antioxidant and anti-inflammatory effects. Recent studies indicate that it modulates multiple biological processes involved in metabolism of carbohydrates and lipids. MGF has been shown to improve metabolic abnormalities and disorders in animal models and humans. This review focuses on the recently reported biological and pharmacological effects of MGF on metabolism and metabolic disorders. © 2016 BioFactors, 42(5):492-503, 2016.
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Affiliation(s)
| | - Yuling Chi
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY.
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134
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Wang S, Wang J, Zhang X, Hu L, Fang Z, Huang Z, Shi P. Trivalent chromium alleviates oleic acid induced steatosis in SMMC-7721 cells by decreasing fatty acid uptake and triglyceride synthesis. Biometals 2016; 29:881-92. [DOI: 10.1007/s10534-016-9960-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 07/28/2016] [Indexed: 12/23/2022]
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Wierzbicki AS, Viljoen A. Anti-sense oligonucleotide therapies for the treatment of hyperlipidaemia. Expert Opin Biol Ther 2016; 16:1125-34. [PMID: 27248482 DOI: 10.1080/14712598.2016.1196182] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Anti-sense oligonucleotide (ASO) therapies are a new development in clinical pharmacology offering greater specificity compared to small molecule inhibitors and the ability to target intracellular process' not susceptible to antibody-based therapies. AREAS COVERED This article reviews the chemical biology of ASOs and related RNA therapeutics. It then reviews the data on their use to treat hyperlipidaemia. Data on mipomersen - an ASO to apolipoprotein B-100(apoB) licensed for treatment of homozygous familial hypercholesterolaemia (FH) is presented. Few effective therapies are available to reduce atehrogenic lipoprotein (a) levels. An ASO therapy to apolipoprotein(a) (ISIS Apo(a)Rx) specifically reduced lipoprotein (a) levels by up to 78%. Treatment options for patients with familial chylomicronaemia syndrome (lipoprotein lipase deficiency; LPLD) or lipodystrophies are highly limited and often inadequate. Volanesorsen, an ASO to apolipoprotein C-3, shows promise in the treatment of LPLD and severe hypertriglyceridaemia as it increases clearance of triglyceride-rich lipoproteins and can normalise triglycerides in these patients. EXPERT OPINION The uptake of the novel ASO therapies is likely to be limited to selected niche groups or orphan diseases. These will include homozygous FH, severe heterozygous FH for mipomersen; LPLD deficiency and lipodystrophy syndromes for volanesorsen and treatment of patients with high elevated Lp(a) levels.
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Affiliation(s)
- Anthony S Wierzbicki
- a Department of Metabolic Medicine/Chemical Pathology , Guy's and St Thomas' Hospitals , London , UK
| | - Adie Viljoen
- b Consultant in Metabolic Medicine/Chemical Pathology , Lister Hospital , Stevenage , UK
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136
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Kobayashi M, Suzuki M, Ohno T, Tsuzuki K, Taguchi C, Tateishi S, Kawada T, Kim YI, Murai A, Horio F. Detection of differentially expressed candidate genes for a fatty liver QTL on mouse chromosome 12. BMC Genet 2016; 17:73. [PMID: 27266874 PMCID: PMC4895971 DOI: 10.1186/s12863-016-0385-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 05/31/2016] [Indexed: 11/30/2022] Open
Abstract
Background The SMXA-5 mouse is an animal model of high-fat diet-induced fatty liver. The major QTL for fatty liver, Fl1sa on chromosome 12, was identified in a SM/J × SMXA-5 intercross. The SMXA-5 genome consists of the SM/J and A/J genomes, and the A/J allele of Fl1sa is a fatty liver-susceptibility allele. The existence of the responsible genes for fatty liver within Fl1sa was confirmed in A/J-12SM consomic mice. The aim of this study was to identify candidate genes for Fl1sa, and to investigate whether the identified genes affect the lipid metabolism. Results A/J-12SM mice showed a significantly lower liver triglyceride content compared to A/J mice when fed the high-fat diet for 7 weeks. We detected differences in the accumulation of liver lipids in response to the high-fat diet between A/J and A/J-12SM consomic mice. To identify candidate genes for Fl1sa, we performed DNA microarray analysis using the livers of A/J-12SM and A/J mice fed the high-fat diet. The mRNA levels of three genes (Iah1, Rrm2, Prkd1) in the chromosomal region of Fl1sa were significantly different between the strains. Iah1 mRNA levels in the liver, kidney, and lung were significantly higher in A/J-12SM mice than in A/J mice. The hepatic Iah1 mRNA level in A/J-12SM mice was 3.2-fold higher than that in A/J mice. To examine the effect of Iah1 on hepatic lipid metabolism, we constructed a stable cell line expressing the mouse Iah1 protein in mouse hepatoma Hepa1-6 cells. Overexpression of Iah1 in Hepa1-6 cells suppressed the mRNA levels of Cd36 and Dgat2, which play important roles in triglyceride synthesis and lipid metabolism. Conclusions These results demonstrated that Fl1sa on the proximal region of chromosome 12 affected fatty liver in mice on a high-fat diet. Iah1 (isoamyl acetate-hydrolyzing esterase 1 homolog) was identified as one of the candidate genes for Fl1sa. This study revealed that the mouse Iah1 gene regulated the expression of genes related to lipid metabolism in the liver. Electronic supplementary material The online version of this article (doi:10.1186/s12863-016-0385-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Misato Kobayashi
- Department of Applied Molecular Bioscience, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan
| | - Miyako Suzuki
- Department of Applied Molecular Bioscience, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan
| | - Tamio Ohno
- Division of Experimental Animals, Center for Promotion of Medical Research and Education, Graduate School of Medicine, Nagoya University, Nagoya, 466-8550, Japan
| | - Kana Tsuzuki
- Department of Applied Molecular Bioscience, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan
| | - Chie Taguchi
- Department of Applied Molecular Bioscience, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan
| | - Soushi Tateishi
- Department of Applied Molecular Bioscience, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan
| | - Teruo Kawada
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, 611-0011, Japan
| | - Young-Il Kim
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, 611-0011, Japan
| | - Atsushi Murai
- Department of Applied Molecular Bioscience, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan
| | - Fumihiko Horio
- Department of Applied Molecular Bioscience, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601, Japan. .,Department of Applied Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya, 464-8601, Japan.
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Omega-3 Fatty Acid-rich Parenteral Nutrition: Is It a Double-edged Sword? J Pediatr Gastroenterol Nutr 2016; 62:e46-7. [PMID: 27111227 DOI: 10.1097/mpg.0000000000001091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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138
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Softic S, Cohen DE, Kahn CR. Role of Dietary Fructose and Hepatic De Novo Lipogenesis in Fatty Liver Disease. Dig Dis Sci 2016; 61:1282-93. [PMID: 26856717 PMCID: PMC4838515 DOI: 10.1007/s10620-016-4054-0] [Citation(s) in RCA: 414] [Impact Index Per Article: 51.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 01/21/2016] [Indexed: 12/11/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a liver manifestation of metabolic syndrome. Overconsumption of high-fat diet (HFD) and increased intake of sugar-sweetened beverages are major risk factors for development of NAFLD. Today the most commonly consumed sugar is high fructose corn syrup. Hepatic lipids may be derived from dietary intake, esterification of plasma free fatty acids (FFA) or hepatic de novo lipogenesis (DNL). A central abnormality in NAFLD is enhanced DNL. Hepatic DNL is increased in individuals with NAFLD, while the contribution of dietary fat and plasma FFA to hepatic lipids is not significantly altered. The importance of DNL in NAFLD is further established in mouse studies with knockout of genes involved in this process. Dietary fructose increases levels of enzymes involved in DNL even more strongly than HFD. Several properties of fructose metabolism make it particularly lipogenic. Fructose is absorbed via portal vein and delivered to the liver in much higher concentrations as compared to other tissues. Fructose increases protein levels of all DNL enzymes during its conversion into triglycerides. Additionally, fructose supports lipogenesis in the setting of insulin resistance as fructose does not require insulin for its metabolism, and it directly stimulates SREBP1c, a major transcriptional regulator of DNL. Fructose also leads to ATP depletion and suppression of mitochondrial fatty acid oxidation, resulting in increased production of reactive oxygen species. Furthermore, fructose promotes ER stress and uric acid formation, additional insulin independent pathways leading to DNL. In summary, fructose metabolism supports DNL more strongly than HFD and hepatic DNL is a central abnormality in NAFLD. Disrupting fructose metabolism in the liver may provide a new therapeutic option for the treatment of NAFLD.
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Affiliation(s)
- Samir Softic
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, One Joslin Place, Boston, MA, 02215, USA
- Department of Gastroenterology, Hepatology and Nutrition, Boston Children's Hospital, Boston, MA, USA
| | - David E Cohen
- Division of Gastroenterology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - C Ronald Kahn
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, One Joslin Place, Boston, MA, 02215, USA.
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139
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Zhang W, Sun Q, Zhong W, Sun X, Zhou Z. Hepatic Peroxisome Proliferator-Activated Receptor Gamma Signaling Contributes to Alcohol-Induced Hepatic Steatosis and Inflammation in Mice. Alcohol Clin Exp Res 2016; 40:988-99. [PMID: 27062444 DOI: 10.1111/acer.13049] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 02/18/2016] [Indexed: 12/25/2022]
Abstract
BACKGROUND Peroxisome proliferator-activated receptor gamma (PPARγ) signaling has been shown to regulate lipogenesis and lipid accumulation. Previous studies have shown that hepatic PPARγ is up-regulated in steatotic liver of both animal and human. However, the effects of hepatic PPARγ signaling on alcoholic liver disease (ALD) remain elusive. METHODS To determine the role of hepatic PPARγ signaling on ALD, wild-type (WT) and hepatocyte-specific PPARγ knockdown (PPARγ∆Hep) mice were fed a modified Lieber-DeCarli alcohol or isocaloric maltose dextrin control liquid diet for 8 weeks to induce ALD. Blood parameters, hepatic steatosis, and inflammation were measured after 8-week alcohol feeding. RESULTS Alcohol feeding to WT mice resulted in liver damage (alanine aminotransferase [ALT], 94.68 ± 17.05 U/L; aspartate aminotransferase [AST], 55.87 ± 11.29 U/L), which was significantly alleviated by hepatic PPARγ knockdown (ALT, 57.36 ± 14.98 U/L; AST, 38.06 ± 3.35 U/L). Alcohol feeding led to marked lipid accumulation and up-regulation of lipogenic genes including fatty acid transport protein 1 (FATP1), acetyl-CoA carboxylase (ACC), fatty acid synthase (FASN), lipin1 (LIPIN1), diacylglycerol acyltransferase 1 (DGAT1), and diacylglycerol acyltransferase 2 (DGAT2) in the livers of WT mice. Knockdown of hepatic PPARγ significantly alleviated alcohol-induced lipid accumulation and abolished the up-regulation of FASN, DGAT1, and DGAT2. Silencing of PPARγ in FL83B cells significantly decreased ethanol (EtOH)-, linoleic acid-, and EtOH plus linoleic acid-induced lipid accumulation. Knockdown of hepatic PPARγ also significantly reduced alcohol-induced inflammatory chemokine (monocyte chemotactic protein 1 [MCP1], keratinocyte-derived chemokine [KC], interferon gamma-induced protein 10 [IP-10]) and inflammatory infiltration (lymphocyte antigen 6 complex, locus G [Ly6G], and F4/80). CONCLUSIONS The results suggest that hepatic PPARγ signaling contributes to alcohol-induced liver injury by promoting hepatic steatosis and inflammation.
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Affiliation(s)
- Wenliang Zhang
- Center for Translational Biomedical Research, University of North Carolina at Greensboro, North Carolina Research Campus, Kannapolis, North Carolina
| | - Qian Sun
- Center for Translational Biomedical Research, University of North Carolina at Greensboro, North Carolina Research Campus, Kannapolis, North Carolina.,Department of Nutrition, University of North Carolina at Greensboro, North Carolina Research Campus, Kannapolis, North Carolina
| | - Wei Zhong
- Center for Translational Biomedical Research, University of North Carolina at Greensboro, North Carolina Research Campus, Kannapolis, North Carolina
| | - Xinguo Sun
- Center for Translational Biomedical Research, University of North Carolina at Greensboro, North Carolina Research Campus, Kannapolis, North Carolina
| | - Zhanxiang Zhou
- Center for Translational Biomedical Research, University of North Carolina at Greensboro, North Carolina Research Campus, Kannapolis, North Carolina.,Department of Nutrition, University of North Carolina at Greensboro, North Carolina Research Campus, Kannapolis, North Carolina
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Tang W, Xu Q, Hong T, Tong G, Feng W, Shen S, Bi Y, Zhu D. Comparative efficacy of anti-diabetic agents on nonalcoholic fatty liver disease in patients with type 2 diabetes mellitus: a systematic review and meta-analysis of randomized and non-randomized studies. Diabetes Metab Res Rev 2016; 32:200-16. [PMID: 26381272 DOI: 10.1002/dmrr.2713] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Revised: 07/10/2015] [Accepted: 07/23/2015] [Indexed: 12/12/2022]
Abstract
BACKGROUND Nonalcoholic fatty liver disease (NAFLD) has a high prevalence in patients with type 2 diabetes mellitus (T2DM). In this study, we sought to provide a comprehensive assessment regarding the effects of anti-diabetic agents on NAFLD in patients with T2DM. METHODS MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials were searched for randomized controlled trials (RCTs) with different anti-diabetic agents in T2DM. Observational trials were also recruited to expand our population. Hepatic fat content and liver histology were evaluated as primary outcomes. Pooled estimates were calculated using a fixed effect model. RESULTS One thousand one hundred ninety-six participants in 19 RCTs and 14 non-randomized studies were included. Evidence from RCTs and observational studies suggested that greater hepatic fat content reduction and improved liver histology were seen in thiazolidinediones for 12-72 weeks; glucagon-like peptide-1 receptor agonists had beneficial effects on hepatic fat content after 26-50 weeks intervention, and insulin/metformin combination with 3-7 months improved hepatic fat content. Initiating metformin or dapagliflozin showed no benefit on hepatic fat content or liver histology in 16-48 weeks. Besides, nateglinide for 18 months was reported in a small sample-size RCT to improve hepatic fat content and liver histology. Sitagliptin therapy of 1 year also provided benefit on nonalcoholic steatohepatitis score in an observational study. CONCLUSIONS For T2DM with NAFLD, administrating thiazolidinediones and glucagon-like peptide-1 receptor agonists seems to provide more identified advances in attenuating hepatic fat content. Further RCTs are warranted to assess the efficacy of various hypoglycemic agents on clinical outcomes associated with NAFLD in T2DM. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Wenjuan Tang
- Department of Endocrinology, Drum Tower Hospital Affiliated to Nanjing University Medical School, Nanjing, China
| | - Qianyue Xu
- Department of Endocrinology, Drum Tower Hospital Affiliated to Nanjing University Medical School, Nanjing, China
| | - Ting Hong
- Department of Endocrinology, Drum Tower Clinical Medical College of Nanjing Medical University, Nanjing, China
| | - Guoyu Tong
- Department of Endocrinology, Drum Tower Hospital Affiliated to Nanjing University Medical School, Nanjing, China
| | - Wenhuan Feng
- Department of Endocrinology, Drum Tower Hospital Affiliated to Nanjing University Medical School, Nanjing, China
| | - Shanmei Shen
- Department of Endocrinology, Drum Tower Hospital Affiliated to Nanjing University Medical School, Nanjing, China
| | - Yan Bi
- Department of Endocrinology, Drum Tower Hospital Affiliated to Nanjing University Medical School, Nanjing, China
| | - Dalong Zhu
- Department of Endocrinology, Drum Tower Hospital Affiliated to Nanjing University Medical School, Nanjing, China
- Department of Endocrinology, Drum Tower Clinical Medical College of Nanjing Medical University, Nanjing, China
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Shin E, Bae JS, Han JY, Lee J, Jeong YS, Lee HJ, Ahn YH, Cha JY. Hepatic DGAT2 gene expression is regulated by the synergistic action of ChREBP and SP1 in HepG2 cells. Anim Cells Syst (Seoul) 2016. [DOI: 10.1080/19768354.2015.1131738] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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142
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Musso G, Cassader M, Gambino R. Non-alcoholic steatohepatitis: emerging molecular targets and therapeutic strategies. Nat Rev Drug Discov 2016; 15:249-74. [PMID: 26794269 DOI: 10.1038/nrd.2015.3] [Citation(s) in RCA: 321] [Impact Index Per Article: 40.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Non-alcoholic fatty liver disease - the most common chronic liver disease - encompasses a histological spectrum ranging from simple steatosis to non-alcoholic steatohepatitis (NASH). Over the next decade, NASH is projected to be the most common indication for liver transplantation. The absence of an effective pharmacological therapy for NASH is a major incentive for research into novel therapeutic approaches for this condition. The current focus areas for research include the modulation of nuclear transcription factors; agents that target lipotoxicity and oxidative stress; and the modulation of cellular energy homeostasis, metabolism and the inflammatory response. Strategies to enhance resolution of inflammation and fibrosis also show promise to reverse the advanced stages of liver disease.
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Affiliation(s)
- Giovanni Musso
- Gradenigo Hospital, Corso Regina Margherita 8, 10132 Turin, Italy
| | - Maurizio Cassader
- Department of Medical Sciences, University of Turin, Corso A.M. Dogliotti 14, 10126, Turin, Italy
| | - Roberto Gambino
- Department of Medical Sciences, University of Turin, Corso A.M. Dogliotti 14, 10126, Turin, Italy
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143
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Matravadia S, Zabielski P, Chabowski A, Mutch DM, Holloway GP. LA and ALA prevent glucose intolerance in obese male rats without reducing reactive lipid content, but cause tissue-specific changes in fatty acid composition. Am J Physiol Regul Integr Comp Physiol 2016; 310:R619-30. [PMID: 26764053 DOI: 10.1152/ajpregu.00297.2015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 01/12/2016] [Indexed: 12/18/2022]
Abstract
While the cause of Type 2 diabetes remains poorly defined, the accumulation of reactive lipids within white adipose tissue, skeletal muscle, and liver have been repeatedly implicated as underlying mechanisms. The ability of polyunsaturated fatty acids (PUFAs) to prevent the development of insulin resistance has gained considerable interest in recent years; however, the mechanisms-of-action remain poorly described. Therefore, we determined the efficacy of diets supplemented with either linoleic acid (LA) or α-linolenic acid (ALA) in preventing insulin resistance and reactive lipid accumulation in key metabolic tissues of the obese Zucker rat. Obese Zucker rats displayed impaired glucose homeostasis and reduced n-3 and n-6 PUFA content in the liver and epididymal white adipose tissue (EWAT). After the 12-wk feeding intervention, both LA- and ALA-supplemented diets prevented whole body glucose and insulin intolerance; however, ALA had a more pronounced effect. These changes occurred in association with n-3 and n-6 accumulation in all tissues studied, albeit to different extents (EWAT > liver > muscle). Triacylglycerol (TAG), diacylglycerol (DAG), ceramide, and sphingolipid accumulation were not attenuated in obese animals supplemented with either LA or ALA, suggesting that preservation of glucose homeostasis occurred independent of changes in reactive lipid content. However, PUFA-supplemented diets differentially altered the fatty acid composition of TAGs, DAGs, and PLs in a tissue-specific manner, suggesting essential fatty acid metabolism differs between tissues. Together, our results indicate that remodeling of the fatty acid composition of various lipid fractions may contribute to the improved glucose tolerance observed in obese rats fed PUFA-supplemented diets.
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Affiliation(s)
- Sarthak Matravadia
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Piotr Zabielski
- Department of Physiology, Medical University of Bialystok, Bialystok, Poland
| | - Adrian Chabowski
- Department of Physiology, Medical University of Bialystok, Bialystok, Poland
| | - David M Mutch
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Graham P Holloway
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada;
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144
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Chen JP, Peng B, Tang L, Sun R, Hu S, Wen XY, Que P, Wang YH. Fetal and infant exposure to the Chinese famine increases the risk of fatty liver disease in Chongqing, China. J Gastroenterol Hepatol 2016. [PMID: 26201820 DOI: 10.1111/jgh.13044] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIM Early life exposure to the famine may affect the susceptibility to the metabolic disorders. The objective of this study was to examine the associations of early life exposure to the Chinese Famine (1959-1961) with the risk of fatty liver disease, obesity, hypertension, and hyperglycemia in adulthood. METHODS We used the data of 10,935 adults born between 1956 and 1965 in Chongqing from check-up center at the 1st Affiliated Hospital of Chongqing Medical University in 2011. Logistic regression models were used to explore the effects of famine on the risk of fatty liver disease, obesity, hypertension, and hyperglycemia. RESULTS In Chongqing, prevalences of fatty liver disease among adults in non-exposed (1956-1958 plus 1963-1965) group and born in 1959, 1960, 1961, and 1962 were 34.01%, 36.42%, 34.63%, 40.27%, and 36.09%, respectively. Prevalences of fatty liver disease, obesity, hypertension, and hyperglycemia were significantly higher in males versus females. The risk of fatty liver disease was about 1.375-fold (1.303 (95% confidence interval, 1.066-1.594) for male, 1.547(95% confidence interval, 1.195-2.002) for female) higher in subjects born in 1961, and 1.142-fold (1.117 (95% confidence interval, 0.957-1.305) for male, 1.242 (95% confidence interval, 1.003-1.537) for female) higher in subjects born in 1962 after adjustment of age and sex, compared with non-exposed subjects. Early life exposure to the Chinese famine was also associated with the increased risk of obesity and hyperglycemia. CONCLUSIONS Exposure to the Chinese famine during fetal life and infancy was associated with an increased risk of fatty liver disease in adulthood.
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Affiliation(s)
- Jiang-Peng Chen
- Department of Health Statistics and Information Management, School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Bin Peng
- Department of Health Statistics and Information Management, School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Lan Tang
- The Public Health Center, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Rong Sun
- The Public Health Center, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Shan Hu
- Department of Health Statistics and Information Management, School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Xiao-Yan Wen
- Department of Health Statistics and Information Management, School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Ping Que
- Department of Health Statistics and Information Management, School of Public Health and Management, Chongqing Medical University, Chongqing, China
| | - Yong-Hong Wang
- The Public Health Center, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
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Boucher MP, Lefebvre C, Chapados NA. The effects of PCB126 on intra-hepatic mechanisms associated with non alcoholic fatty liver disease. J Diabetes Metab Disord 2015; 14:88. [PMID: 26693162 PMCID: PMC4676123 DOI: 10.1186/s40200-015-0218-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 11/26/2015] [Indexed: 01/19/2023]
Abstract
Background Non alcoholic fatty liver disease (NAFLD) results from alteration in lipid synthesis and elimination mechanisms such as very-low density lipoprotein (VLDL) production and de novo lipogenesis. Persistent organic pollutants (POPs) are chemicals that were mostly used historically as pesticides, solvents, flame retardant, and other applications. Among POPs, polychlorinated biphenyls (PCB) have been recognized to be of environmental and potential toxicologic concerns. Specifically, PCB126 could act as endocrine disruptors and has recently been associated with hepatic fat accumulation. The purpose of the study was to investigate the effects of PCB126 on the molecular development of NAFLD using hepatocyte and rat models. Methods Hepatocytes were exposed to PCB 126 for 72 h and lipid accumulation in cells was quantified by Oil-Red-O. Rats were injected with a single dose of PCB126 or vehicle. Seven days later, liver triglycerides (TAG) content was measured along with protein quantification of hepatic microsomal triglyceride transfer protein (MTP), sterol regulatory element-binding protein 1c (SREBP1c) and diacylglycerol O-acyltransferase 2 (DGAT-2). Results Exposure to PCB126 resulted in significant increases of lipid accumulation in hepatocytes (38 %, P <0.05) and hepatic TAG concentrations (64 %, P <0.001) in rats compared to respective control groups. Rats with fatty livers depicted lower MTP (40 %, P <0.02), higher SREBP1c (27 %, P < 0.05) and DGAT-2 (120 %, P < 0.02) protein content levels compared to Placebo group in rats. Conclusions It seems that exposure to PCB126 has an important emerging role in the pathophysiology of NAFLD by 1) altering elimination mechanisms such as VLDL synthesis and secretion, through MTP; and 2) increasing hepatic TAG synthesis mechanisms through DGAT 2 and SREBP1c.
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Affiliation(s)
| | | | - Natalie Ann Chapados
- Institut de recherche de l`Hôpital Montfort, Hôpital Montfort, 713 Montreal Road, Ottawa, ON K1K 0T2 Canada ; School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, Ottawa, ON Canada
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146
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Popov VB, Jornayvaz FR, Akgul EO, Kanda S, Jurczak MJ, Zhang D, Abudukadier A, Majumdar SK, Guigni B, Petersen KF, Manchem VP, Bhanot S, Shulman GI, Samuel VT. Second-generation antisense oligonucleotides against β-catenin protect mice against diet-induced hepatic steatosis and hepatic and peripheral insulin resistance. FASEB J 2015; 30:1207-17. [PMID: 26644352 DOI: 10.1096/fj.15-271999] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 11/16/2015] [Indexed: 12/24/2022]
Abstract
Although mutations in the Wnt/β-catenin signaling pathway are linked with the metabolic syndrome and type 2 diabetes in humans, the mechanism is unclear. High-fat-fed male C57BL/6 mice were treated for 4 wk with a 2'-O-methoxyethyl chimeric antisense oligonucleotide (ASO) to decrease hepatic and adipose expression of β-catenin. β-Catenin mRNA decreased by ≈80% in the liver and by 70% in white adipose tissue relative to control ASO-treated mice. β-Catenin ASO improved hepatic insulin sensitivity and increased insulin-stimulated whole body glucose metabolism, as assessed during hyperinsulinemic-euglycemic clamp in awake mice. β-Catenin ASO altered hepatic lipid composition in high-fat-fed mice. There were reductions in hepatic triglyceride (44%, P < 0.05) and diacylglycerol content (60%, P < 0.01) but a 30% increase in ceramide content (P < 0.001). The altered lipid content was attributed to decreased expression of sn-1,2 diacylglycerol acyltransferase and mitochondrial acyl-CoA:glycerol-sn-3-phosphate acyltransferase and an increase in serine palmitoyl transferase. The decrease in cellular diacyglycerol was associated with a 33% decrease in PKCε activation (P < 0.05) and 64% increase in Akt2 phosphorylation (P < 0.05). In summary, Reducing β-catenin expression decreases expression of enzymes involved in hepatic fatty acid esterification, ameliorates hepatic steatosis and lipid-induced insulin resistance.
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Affiliation(s)
- Violeta B Popov
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
| | - Francois R Jornayvaz
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
| | - Emin O Akgul
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
| | - Shoichi Kanda
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
| | - Michael J Jurczak
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
| | - Dongyan Zhang
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
| | - Abulizi Abudukadier
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
| | - Sachin K Majumdar
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
| | - Blas Guigni
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
| | - Kitt Falk Petersen
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
| | - Vara Prasad Manchem
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
| | - Sanjay Bhanot
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
| | - Gerald I Shulman
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
| | - Varman T Samuel
- *Department of Internal Medicine, Department of Cellular and Molecular Physiology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut, USA; West Haven Veterans Affairs Medical Center, West Haven, Connecticut, USA; and ISIS Pharmaceuticals, Carlsbad, California, USA
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147
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Imbriglio JE, Shen DM, Liang R, Marby K, You M, Youm HW, Feng Z, London C, Xiong Y, Tata J, Verras A, Garcia-Calvo M, Song X, Addona GH, McLaren DG, He T, Murphy B, Metzger DE, Salituro G, Deckman D, Chen Q, Jin X, Stout SJ, Wang SP, Wilsie L, Palyha O, Han S, Hubbard BK, Previs SF, Pinto S, Taggart A. Discovery and Pharmacology of a Novel Class of Diacylglycerol Acyltransferase 2 Inhibitors. J Med Chem 2015; 58:9345-53. [PMID: 26561979 DOI: 10.1021/acs.jmedchem.5b01345] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
DGAT2 plays a critical role in hepatic triglyceride production, and data suggests that inhibition of DGAT2 could prove to be beneficial in treating a number of disease states. This article documents the discovery and optimization of a selective small molecule inhibitor of DGAT2 as well as pharmacological proof of biology in a mouse model of triglyceride production.
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Affiliation(s)
- Jason E Imbriglio
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Dong-Ming Shen
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Rui Liang
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Ken Marby
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Ming You
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Hye Won Youm
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Zhe Feng
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Clare London
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Yusheng Xiong
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Jim Tata
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Andreas Verras
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Margarita Garcia-Calvo
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Xuelei Song
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - George H Addona
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Dave G McLaren
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Timothy He
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Beth Murphy
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Dan E Metzger
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Gino Salituro
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Diana Deckman
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Qing Chen
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Xiaoling Jin
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Steven J Stout
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Sheng-Ping Wang
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Larissa Wilsie
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Oksana Palyha
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Seongah Han
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Brian K Hubbard
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Stephen F Previs
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Shirly Pinto
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Andrew Taggart
- Department of Discovery Chemistry, ‡Chemistry Modeling, and Informatics, §In Vitro Pharmacology, ∥In Vivo Pharmacology, ⊥Pharmacokinetics, Pharmacodynamics, and Drug Metabolism, #Basic Pharmaceutical Sciences, and ○Atherosclerosis, Merck & Co., Inc. , 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
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148
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Imran M, Butt MS, Akhtar S, Riaz M, Iqbal MJ, Suleria HAR. Quantification of Mangiferin by High Pressure Liquid Chromatography; Physicochemical and Sensory Evaluation of Functional Mangiferin Drink. J FOOD PROCESS PRES 2015. [DOI: 10.1111/jfpp.12657] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Muhammad Imran
- Department of Food Science and Technology; BZU; Multan Pakistan
- National Institute of Food Science and Technology; University of Agriculture Faisalabad; Faisalabad Pakistan
| | - Masood Sadiq Butt
- National Institute of Food Science and Technology; University of Agriculture Faisalabad; Faisalabad Pakistan
| | - Saeed Akhtar
- Department of Food Science and Technology; BZU; Multan Pakistan
| | - Muhammad Riaz
- Department of Food Science and Technology; BZU; Multan Pakistan
| | - Muhammad Jawad Iqbal
- National Institute of Food Science and Technology; University of Agriculture Faisalabad; Faisalabad Pakistan
| | - Hafiz Ansar Rasul Suleria
- National Institute of Food Science and Technology; University of Agriculture Faisalabad; Faisalabad Pakistan
- UQ School of Medicine; The University of Queensland; 207 Sir Fred Schonell Drive Brisbane Queensland 4067 Australia
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149
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Abstract
Parenteral nutrition (PN) has been strongly associated with intestinal failure-associated liver disease. Cholestasis, liver steatosis, and liver fibrosis are features of this liver injury, which can progress to end stage liver disease. Omega-3 fatty acid rich PN has been shown to alleviate cholestasis and steatosis. There have been reports although suggesting that it may not be able to arrest or reverse the progression to liver fibrosis. In this article, we develop a hypothesis of the mechanism of how Ω-3 fatty acid rich PN may influence the progression of fibrosis.
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150
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Bonen A, Jain SS, Snook LA, Han XX, Yoshida Y, Buddo KH, Lally JS, Pask ED, Paglialunga S, Beaudoin MS, Glatz JFC, Luiken JJFP, Harasim E, Wright DC, Chabowski A, Holloway GP. Extremely rapid increase in fatty acid transport and intramyocellular lipid accumulation but markedly delayed insulin resistance after high fat feeding in rats. Diabetologia 2015. [PMID: 26197708 DOI: 10.1007/s00125-015-3691-8] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
AIMS/HYPOTHESIS The mechanisms for diet-induced intramyocellular lipid accumulation and its association with insulin resistance remain contentious. In a detailed time-course study in rats, we examined whether a high-fat diet increased intramyocellular lipid accumulation via alterations in fatty acid translocase (FAT/CD36)-mediated fatty acid transport, selected enzymes and/or fatty acid oxidation, and whether intramyocellular lipid accretion coincided with the onset of insulin resistance. METHODS We measured, daily (on days 1-7) and/or weekly (for 6 weeks), the diet-induced changes in circulating substrates, insulin, sarcolemmal substrate transporters and transport, selected enzymes, intramyocellular lipids, mitochondrial fatty acid oxidation and basal and insulin-stimulated sarcolemmal GLUT4 and glucose transport. We also examined whether upregulating fatty acid oxidation improved glucose transport in insulin-resistant muscles. Finally, in Cd36-knockout mice, we examined the role of FAT/CD36 in intramyocellular lipid accumulation, insulin sensitivity and diet-induced glucose intolerance. RESULTS Within 2-3 days, diet-induced increases occurred in insulin, sarcolemmal FAT/CD36 (but not fatty acid binding protein [FABPpm] or fatty acid transporter [FATP]1 or 4), fatty acid transport and intramyocellular triacylglycerol, diacylglycerol and ceramide, independent of enzymatic changes or muscle fatty acid oxidation. Diet-induced increases in mitochondria and mitochondrial fatty acid oxidation and impairments in insulin-stimulated glucose transport and GLUT4 translocation occurred much later (≥21 days). FAT/CD36 ablation impaired insulin-stimulated fatty acid transport and lipid accumulation, improved insulin sensitivity and prevented diet-induced glucose intolerance. Increasing fatty acid oxidation in insulin-resistant muscles improved glucose transport. CONCLUSIONS/INTERPRETATIONS High-fat feeding rapidly increases intramyocellular lipids (in 2-3 days) via insulin-mediated upregulation of sarcolemmal FAT/CD36 and fatty acid transport. The 16-19 day delay in the onset of insulin resistance suggests that additional mechanisms besides intramyocellular lipids contribute to this pathology.
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Affiliation(s)
- Arend Bonen
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada, N1G 2W1.
| | - Swati S Jain
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - Laelie A Snook
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - Xiao-Xia Han
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - Yuko Yoshida
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - Kathryn H Buddo
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - James S Lally
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - Elizabeth D Pask
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - Sabina Paglialunga
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - Marie-Soleil Beaudoin
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - Jan F C Glatz
- Department of Molecular Genetics, Maastricht University, Maastricht, the Netherlands
| | - Joost J F P Luiken
- Department of Molecular Genetics, Maastricht University, Maastricht, the Netherlands
| | - Ewa Harasim
- Department of Physiology, Medical University of Bialystok, Bialystok, Poland
| | - David C Wright
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada, N1G 2W1
| | - Adrian Chabowski
- Department of Physiology, Medical University of Bialystok, Bialystok, Poland
| | - Graham P Holloway
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, ON, Canada, N1G 2W1
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