1
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Osonoi S, Takebe T. Organoid-guided precision hepatology for metabolic liver disease. J Hepatol 2024; 80:805-821. [PMID: 38237864 DOI: 10.1016/j.jhep.2024.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 12/28/2023] [Accepted: 01/02/2024] [Indexed: 03/09/2024]
Abstract
Metabolic dysfunction-associated steatotic liver disease affects millions of people worldwide. Progress towards a definitive cure has been incremental and treatment is currently limited to lifestyle modification. Hepatocyte-specific lipid accumulation is the main trigger of lipotoxic events, driving inflammation and fibrosis. The underlying pathology is extraordinarily heterogenous, and the manifestations of steatohepatitis are markedly influenced by metabolic communications across non-hepatic organs. Synthetic human tissue models have emerged as powerful platforms to better capture the mechanistic diversity in disease progression, while preserving person-specific genetic traits. In this review, we will outline current research efforts focused on integrating multiple synthetic tissue models of key metabolic organs, with an emphasis on organoid-based systems. By combining functional genomics and population-scale en masse profiling methodologies, human tissues derived from patients can provide insights into personalised genetic, transcriptional, biochemical, and metabolic states. These collective efforts will advance our understanding of steatohepatitis and guide the development of rational solutions for mechanism-directed diagnostic and therapeutic investigation.
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Affiliation(s)
- Sho Osonoi
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Gastroenterology, Hepatology and Nutrition, Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki, 036-8562, Japan
| | - Takanori Takebe
- Center for Stem Cell and Organoid Medicine (CuSTOM), Division of Gastroenterology, Hepatology and Nutrition, Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA; WPI Premium Institute for Human Metaverse Medicine (WPI-PRIMe) and Department of Genome Biology, Graduate School of Medicine, Osaka University, Osaka, 565-0871, Japan; Institute of Research, Tokyo Medical and Dental University (TMDU), Tokyo 113-8510, Japan; Communication Design Center, Advanced Medical Research Center, Yokohama City University, Yokohama 236-0004, Japan.
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2
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van Zwol W, van de Sluis B, Ginsberg HN, Kuivenhoven JA. VLDL Biogenesis and Secretion: It Takes a Village. Circ Res 2024; 134:226-244. [PMID: 38236950 PMCID: PMC11284300 DOI: 10.1161/circresaha.123.323284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 09/21/2023] [Indexed: 01/23/2024]
Abstract
The production and secretion of VLDLs (very-low-density lipoproteins) by hepatocytes has a direct impact on liver fat content, as well as the concentrations of cholesterol and triglycerides in the circulation and thus affects both liver and cardiovascular health, respectively. Importantly, insulin resistance, excess caloric intake, and lack of physical activity are associated with overproduction of VLDL, hepatic steatosis, and increased plasma levels of atherogenic lipoproteins. Cholesterol and triglycerides in remnant particles generated by VLDL lipolysis are risk factors for atherosclerotic cardiovascular disease and have garnered increasing attention over the last few decades. Presently, however, increased risk of atherosclerosis is not the only concern when considering today's cardiometabolic patients, as they often also experience hepatic steatosis, a prevalent disorder that can progress to steatohepatitis and cirrhosis. This duality of metabolic risk highlights the importance of understanding the molecular regulation of the biogenesis of VLDL, the lipoprotein that transports triglycerides and cholesterol out of the liver. Fortunately, there has been a resurgence of interest in the intracellular assembly, trafficking, degradation, and secretion of VLDL by hepatocytes, which has led to many exciting new molecular insights that are the topic of this review. Increasing our understanding of the biology of this pathway will aid to the identification of novel therapeutic targets to improve both the cardiovascular and the hepatic health of cardiometabolic patients. This review focuses, for the first time, on this duality.
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Affiliation(s)
- Willemien van Zwol
- Department of Paediatrics, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Bart van de Sluis
- Department of Paediatrics, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Henry. N. Ginsberg
- Department of Medicine, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Jan Albert Kuivenhoven
- Department of Paediatrics, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
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3
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Filipski KJ, Edmonds DJ, Garnsey MR, Smaltz DJ, Coffman K, Futatsugi K, Lee J, O’Neil SV, Wright A, Nason D, Gosset JR, Orozco CC, Blackler D, Fakhoury G, Gutierrez JA, Perez S, Ross T, Stock I, Tesz G, Dullea R. Design of Next-Generation DGAT2 Inhibitor PF-07202954 with Longer Predicted Half-Life. ACS Med Chem Lett 2023; 14:1427-1433. [PMID: 37849537 PMCID: PMC10577701 DOI: 10.1021/acsmedchemlett.3c00330] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 09/26/2023] [Indexed: 10/19/2023] Open
Abstract
Diacylglycerol O-acyltransferase 2 (DGAT2) inhibitors have been shown to lower liver triglyceride content and are being explored clinically as a treatment for non-alcoholic steatohepatitis (NASH). This work details efforts to find an extended-half-life DGAT2 inhibitor. A basic moiety was added to a known inhibitor template, and the basicity and lipophilicity were fine-tuned by the addition of electrophilic fluorines. A weakly basic profile was required to find an appropriate balance of potency, clearance, and permeability. This work culminated in the discovery of PF-07202954 (12), a weakly basic DGAT2 inhibitor that has advanced to clinical studies. This molecule displays a higher volume of distribution and longer half-life in preclinical species, in keeping with its physicochemical profile, and lowers liver triglyceride content in a Western-diet-fed rat model.
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Affiliation(s)
- Kevin J. Filipski
- Pfizer
Research & Development, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - David J. Edmonds
- Pfizer
Research & Development, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Michelle R. Garnsey
- Pfizer
Research & Development, 1 Portland Street, Cambridge, Massachusetts 02139, United States
- Pfizer
Research & Development, 558 Eastern Point Road, Groton, Connecticut 06340, United States
| | - Daniel J. Smaltz
- Pfizer
Research & Development, 1 Portland Street, Cambridge, Massachusetts 02139, United States
- Pfizer
Research & Development, 558 Eastern Point Road, Groton, Connecticut 06340, United States
| | - Karen Coffman
- Pfizer
Research & Development, 558 Eastern Point Road, Groton, Connecticut 06340, United States
| | - Kentaro Futatsugi
- Pfizer
Research & Development, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Jack Lee
- Pfizer
Research & Development, 558 Eastern Point Road, Groton, Connecticut 06340, United States
| | - Steven V. O’Neil
- Pfizer
Research & Development, 558 Eastern Point Road, Groton, Connecticut 06340, United States
| | - Ann Wright
- Pfizer
Research & Development, 558 Eastern Point Road, Groton, Connecticut 06340, United States
| | - Deane Nason
- Pfizer
Research & Development, 558 Eastern Point Road, Groton, Connecticut 06340, United States
| | - James R. Gosset
- Pfizer
Research & Development, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Christine C. Orozco
- Pfizer
Research & Development, 558 Eastern Point Road, Groton, Connecticut 06340, United States
| | - Dan Blackler
- Pfizer
Research & Development, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Guila Fakhoury
- Pfizer
Research & Development, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Jemy A. Gutierrez
- Pfizer
Research & Development, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Sylvie Perez
- Pfizer
Research & Development, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Trenton Ross
- Pfizer
Research & Development, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Ingrid Stock
- Pfizer
Research & Development, 558 Eastern Point Road, Groton, Connecticut 06340, United States
| | - Gregory Tesz
- Pfizer
Research & Development, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Robert Dullea
- Pfizer
Research & Development, 1 Portland Street, Cambridge, Massachusetts 02139, United States
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Guo PP, Jin X, Zhang JF, Li Q, Yan CG, Li XZ. Overexpression of DGAT2 Regulates the Differentiation of Bovine Preadipocytes. Animals (Basel) 2023; 13:ani13071195. [PMID: 37048451 PMCID: PMC10093762 DOI: 10.3390/ani13071195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/25/2023] [Accepted: 03/27/2023] [Indexed: 04/01/2023] Open
Abstract
Triacylglycerols (TAGs) are a major component of intramuscular fat. Diacylglycerol O-acyltransferase 2(DGAT2) expression determines the rate of TAG synthesis. The purpose of this study was to investigate the role of DGAT2 in the differentiation of Yanbian cattle preadipocytes and lipid metabolism-related signalling pathways. Bovine preadipocytes were infected with overexpression and interfering adenovirus vectors of DGAT2. The effects on the differentiation of Yanbian cattle preadipocytes were examined using molecular and transcriptomic techniques, including differentially expressed genes (DEGs) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analysis. DGAT2 overexpression significantly increased (p < 0.05) intracellular TAG, adiponectin, and lipid droplet (LD) contents. Moreover, it upregulated (p < 0.05) peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding protein α, and fatty acid binding protein 4 mRNA expression. In contrast, DGAT2 knockdown reduced intracellular TAG and LD content and downregulated (p < 0.05) C/EBPβ, mannosyl (alpha-1,3-)-glycoproteinbeta-1,2-N-acetylglucosaminyltransferase, lipin 1,1-acylglycerol-3-phosphate O-acyltransferase 4, and acetyl-CoA carboxylase alpha mRNA expression. Between DGAT2-overexpressing preadipocytes and normal cells, 208 DEGs were identified, including 106 upregulated and 102 downregulated genes. KEGG pathway analysis revealed DEGs mainly enriched in PPAR signalling and AMP-activated protein kinase pathways, cholesterol metabolism, and fatty acid biosynthesis. These results demonstrated that DGAT2 regulated preadipocyte differentiation and LD and TAG accumulation by mediating the expression of adipose differentiation-, lipid metabolism-, and fatty acid synthesis-related genes.
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Sharma AK, Wang T, Othman A, Khandelwal R, Balaz M, Modica S, Zamboni N, Wolfrum C. Basal re-esterification finetunes mitochondrial fatty acid utilization. Mol Metab 2023; 71:101701. [PMID: 36878315 PMCID: PMC10011057 DOI: 10.1016/j.molmet.2023.101701] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 02/27/2023] [Accepted: 02/28/2023] [Indexed: 03/06/2023] Open
Abstract
OBJECTIVE Emerging evidence suggest the existence of constant basal lipolysis and re-esterification of a substantial fraction of thus liberated fatty acids. In stimulated lipolysis, the re-esterification is proposed to be a protective mechanism against lipotoxicity; however, the role of the lipolysis coupled to re-esterification under basal conditions has not been deciphered. METHODS We used adipocytes (in vitro differentiated brown and white adipocytes derived from a cell line or primary SVF culture) to study the effect of inhibition of re-esterification by pharmacological DGAT1 and DGAT2 inhibitors alone or in combination. We then evaluated cellular energetics, lipolysis flux, and lipidomic parameters along with mitochondrial properties and fuel utilization. RESULTS In adipocytes, DGAT1 and 2 mediated re-esterification is a moderator of fatty acid oxidation. Combined inhibition of both DGATs (D1+2i) increases oxygen consumption, which is largely due to enhanced mitochondrial respiration by lipolysis-derived fatty acids (FAs). Acute D1+2i selectively affects mitochondrial respiration without affecting the transcriptional homeostasis of genes relevant to mitochondrial health and lipid metabolism. D1+2i enhances the mitochondrial import of pyruvate and activates AMP Kinase to counteract CPT1 antagonism, thus facilitating the mitochondrial import of fatty acyl-CoA. CONCLUSIONS These data implicate the process of re-esterification in the regulation of mitochondrial FA usage and uncover a mechanism of FAO regulation via crosstalk with FA re-esterification.
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Affiliation(s)
- Anand Kumar Sharma
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland
| | - Tongtong Wang
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland
| | - Alaa Othman
- Department of Biology, Institute of Molecular Systems Biology, ETH Zürich, Zürich, Switzerland
| | - Radhika Khandelwal
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland
| | - Miroslav Balaz
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland; Laboratory of Cellular and Molecular Metabolism, Biomedical Research Center, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Salvatore Modica
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland
| | - Nicola Zamboni
- Department of Biology, Institute of Molecular Systems Biology, ETH Zürich, Zürich, Switzerland
| | - Christian Wolfrum
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland.
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6
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Amin NB, Saxena AR, Somayaji V, Dullea R. Inhibition of Diacylglycerol Acyltransferase 2 Versus Diacylglycerol Acyltransferase 1: Potential Therapeutic Implications of Pharmacology. Clin Ther 2023; 45:55-70. [PMID: 36690550 DOI: 10.1016/j.clinthera.2022.12.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 12/01/2022] [Accepted: 12/15/2022] [Indexed: 01/22/2023]
Abstract
PURPOSE Hepatic steatosis due to altered lipid metabolism and accumulation of hepatic triglycerides is a hallmark of nonalcoholic fatty liver disease (NAFLD). Diacylglycerol acyltransferase (DGAT) enzymes, DGAT1 and DGAT2, catalyze the terminal reaction in triglyceride synthesis, making them attractive targets for pharmacologic intervention. There is a common misconception that these enzymes are related; however, despite their similar names, DGAT1 and DGAT2 differ significantly on multiple levels. As we look ahead to future clinical studies of DGAT2 inhibitors in patients with NAFLD and nonalcoholic steatohepatitis (NASH), we review key differences and include evidence to highlight and support DGAT2 inhibitor (DGAT2i) pharmacology. METHODS Three Phase I, randomized, double-blind, placebo-controlled trials assessed the safety, tolerability, and pharmacokinetic properties of the DGAT2i ervogastat (PF-06865571) in healthy adult participants (Single Dose Study to Assess the Safety, Tolerability and Pharmacokinetics of PF-06865571 [study C2541001] and Study to Assess the Safety, Tolerability, and Pharmacokinetics of Multiple Doses of PF-06865571 in Healthy, Including Overweight and Obese, Adult Subjects [study C2541002]) or participants with NAFLD (2-Week Study in People With Nonalcoholic Fatty Liver Disease [study C2541005]). Data from 2 Phase I, randomized, double-blind, placebo-controlled trials of the DGAT1i PF-04620110 in healthy participants (A Single Dose Study of PF-04620110 in Overweight and Obese, Otherwise Healthy Volunteers [study B0961001] and A Multiple Dose Study of PF-04620110 in Overweight and Obese, Otherwise Healthy Volunteers [study B0961002]) were included for comparison. Safety outcomes were the primary end point in all studies, except in study C2541005, in which safety was the secondary end point, with relative change from baseline in whole liver fat at day 15 assessed as the primary end point. Safety data were analyzed across studies by total daily dose of ervogastat (5, 15, 50, 100, 150, 500, 600, 1000, and 1500 mg) or PF-04620110 (0.3, 1, 3, 5, 7, 10, 14, and 21 mg), with placebo data pooled separately across ervogastat and PF-04620110 studies. FINDINGS Published data indicate that DGAT1 and DGAT2 differ in multiple dimensions, including gene family, subcellular localization, substrate preference, and specificity, with unrelated pharmacologic inhibition properties and differing safety profiles. Although initial nonclinical studies suggested a potentially attractive therapeutic profile with DGAT1 inhibition, genetic and pharmacologic data suggest otherwise, with common gastrointestinal adverse events, including nausea, vomiting, and diarrhea, limiting further clinical development. Conversely, DGAT2 inhibition, although initially not pursued as aggressively as a potential target for pharmacologic intervention, has consistent efficacy in nonclinical studies, with reduced triglyceride synthesis accompanied by reduced expression of genes essential for de novo lipogenesis. In addition, early clinical data indicate antisteatotic effects with DGAT2i ervogastat, in participants with NAFLD, accompanied by a well-tolerated safety profile. IMPLICATIONS Although pharmacologic DGAT1is are limited by an adverse safety profile, data support use of DGAT2i as an effective and well-tolerated therapeutic strategy for patients with NAFLD, NASH, and NASH with liver fibrosis. CLINICALTRIALS gov identifiers: NCT03092232, NCT03230383, NCT03513588, NCT00799006, and NCT00959426.
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Affiliation(s)
- Neeta B Amin
- Internal Medicine Research Unit, Pfizer Inc, Cambridge, Massachusetts
| | - Aditi R Saxena
- Internal Medicine Research Unit, Pfizer Inc, Cambridge, Massachusetts
| | - Veena Somayaji
- Early Clinical Development, Pfizer Inc, Cambridge, Massachusetts
| | - Robert Dullea
- Internal Medicine Research Unit, Pfizer Inc, Cambridge, Massachusetts.
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7
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Dong Q, Bao H, Wang J, Shi W, Zou X, Sheng J, Gao J, Guan C, Xia H, Li J, Kang P, Xu Y, Cui Y, Zhong X. Liver fibrosis and MAFLD: the exploration of multi-drug combination therapy strategies. Front Med (Lausanne) 2023; 10:1120621. [PMID: 37153080 PMCID: PMC10157161 DOI: 10.3389/fmed.2023.1120621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Accepted: 03/22/2023] [Indexed: 05/09/2023] Open
Abstract
In recent years, the prevalence of metabolic-associated fatty liver disease (MAFLD) has reached pandemic proportions as a leading cause of liver fibrosis worldwide. However, the stage of liver fibrosis is associated with an increased risk of severe liver-related and cardiovascular events and is the strongest predictor of mortality in MAFLD patients. More and more people believe that MAFLD is a multifactorial disease with multiple pathways are involved in promoting the progression of liver fibrosis. Numerous drug targets and drugs have been explored for various anti-fibrosis pathways. The treatment of single medicines is brutal to obtain satisfactory results, so the strategies of multi-drug combination therapies have attracted increasing attention. In this review, we discuss the mechanism of MAFLD-related liver fibrosis and its regression, summarize the current intervention and treatment methods for this disease, and focus on the analysis of drug combination strategies for MAFLD and its subsequent liver fibrosis in recent years to explore safer and more effective multi-drug combination therapy strategies.
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Affiliation(s)
- Qingfu Dong
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Haolin Bao
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Jiangang Wang
- Department of General Surgery, Tangdu Hospital, Air Force Medical University, Xi'an, Shaanxi, China
| | - Wujiang Shi
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Xinlei Zou
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Jialin Sheng
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Jianjun Gao
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Canghai Guan
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Haoming Xia
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Jinglin Li
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Pengcheng Kang
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Yi Xu
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
- Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Zunyi, Guizhou, China
- Key Laboratory of Functional and Clinical Translational Medicine, Fujian Province University, Xiamen Medical College, Xiamen, Fujian, China
- Jiangsu Province Engineering Research Center of Tumor Targeted Nano Diagnostic and Therapeutic Materials, Yancheng Teachers University, Yancheng, Jiangsu, China
- Key Laboratory of Biomarkers and In Vitro Diagnosis Translation of Zhejiang Province, Hangzhou, Zhejiang, China
- Key Laboratory of Gastrointestinal Cancer, Ministry of Education, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, China
- State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen, Guangdong, China
- Department of Pathology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
- Key Laboratory of Intelligent Pharmacy and Individualized Therapy of Huzhou, Department of Pharmacy, Changxing People's Hospital, Changxing, Zhejiang, China
- Yi Xu
| | - Yunfu Cui
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
- Yunfu Cui
| | - Xiangyu Zhong
- Department of Hepatopancreatobiliary Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
- *Correspondence: Xiangyu Zhong
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8
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Futatsugi K, Cabral S, Kung DW, Huard K, Lee E, Boehm M, Bauman J, Clark RW, Coffey SB, Crowley C, Dechert-Schmitt AM, Dowling MS, Dullea R, Gosset JR, Kalgutkar AS, Kou K, Li Q, Lian Y, Loria PM, Londregan AT, Niosi M, Orozco C, Pettersen JC, Pfefferkorn JA, Polivkova J, Ross TT, Sharma R, Stock IA, Tesz G, Wisniewska H, Goodwin B, Price DA. Discovery of Ervogastat (PF-06865571): A Potent and Selective Inhibitor of Diacylglycerol Acyltransferase 2 for the Treatment of Non-alcoholic Steatohepatitis. J Med Chem 2022; 65:15000-15013. [PMID: 36322383 DOI: 10.1021/acs.jmedchem.2c01200] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Discovery efforts leading to the identification of ervogastat (PF-06865571), a systemically acting diacylglycerol acyltransferase (DGAT2) inhibitor that has advanced into clinical trials for the treatment of non-alcoholic steatohepatitis (NASH) with liver fibrosis, are described herein. Ervogastat is a first-in-class DGAT2 inhibitor that addressed potential development risks of the prototype liver-targeted DGAT2 inhibitor PF-06427878. Key design elements that culminated in the discovery of ervogastat are (1) replacement of the metabolically labile motif with a 3,5-disubstituted pyridine system, which addressed potential safety risks arising from a cytochrome P450-mediated O-dearylation of PF-06427878 to a reactive quinone metabolite precursor, and (2) modifications of the amide group to a 3-THF group, guided by metabolite identification studies coupled with property-based drug design.
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Affiliation(s)
- Kentaro Futatsugi
- Pfizer Inc. Medicine Design, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Shawn Cabral
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Daniel W Kung
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Kim Huard
- Pfizer Inc. Medicine Design, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Esther Lee
- Pfizer Inc. Medicine Design, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Markus Boehm
- Pfizer Inc. Medicine Design, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Jonathan Bauman
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Ronald W Clark
- Pfizer Inc. Internal Medicine Research Unit, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Steven B Coffey
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Collin Crowley
- Pfizer Inc. Internal Medicine Research Unit, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | | | - Matthew S Dowling
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Robert Dullea
- Pfizer Inc. Internal Medicine Research Unit, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - James R Gosset
- Pfizer Inc. Medicine Design, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Amit S Kalgutkar
- Pfizer Inc. Medicine Design, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Kou Kou
- Pfizer Inc. Internal Medicine Research Unit, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Qifang Li
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Yajing Lian
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Paula M Loria
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Allyn T Londregan
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Mark Niosi
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Christine Orozco
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - John C Pettersen
- Pfizer Inc. Drug Safety R&D, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Jeffrey A Pfefferkorn
- Pfizer Inc. Internal Medicine Research Unit, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Jana Polivkova
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Trenton T Ross
- Pfizer Inc. Internal Medicine Research Unit, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Raman Sharma
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Ingrid A Stock
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Gregory Tesz
- Pfizer Inc. Internal Medicine Research Unit, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - Hanna Wisniewska
- Pfizer Inc. Medicine Design, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Bryan Goodwin
- Pfizer Inc. Internal Medicine Research Unit, 1 Portland Street, Cambridge, Massachusetts 02139, United States
| | - David A Price
- Pfizer Inc. Medicine Design, 1 Portland Street, Cambridge, Massachusetts 02139, United States
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9
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Chen G, Harwood JL, Lemieux MJ, Stone SJ, Weselake RJ. Acyl-CoA:diacylglycerol acyltransferase: Properties, physiological roles, metabolic engineering and intentional control. Prog Lipid Res 2022; 88:101181. [PMID: 35820474 DOI: 10.1016/j.plipres.2022.101181] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 05/31/2022] [Accepted: 07/04/2022] [Indexed: 12/15/2022]
Abstract
Acyl-CoA:diacylglycerol acyltransferase (DGAT, EC 2.3.1.20) catalyzes the last reaction in the acyl-CoA-dependent biosynthesis of triacylglycerol (TAG). DGAT activity resides mainly in membrane-bound DGAT1 and DGAT2 in eukaryotes and bifunctional wax ester synthase-diacylglycerol acyltransferase (WSD) in bacteria, which are all membrane-bound proteins but exhibit no sequence homology to each other. Recent studies also identified other DGAT enzymes such as the soluble DGAT3 and diacylglycerol acetyltransferase (EaDAcT), as well as enzymes with DGAT activities including defective in cuticular ridges (DCR) and steryl and phytyl ester synthases (PESs). This review comprehensively discusses research advances on DGATs in prokaryotes and eukaryotes with a focus on their biochemical properties, physiological roles, and biotechnological and therapeutic applications. The review begins with a discussion of DGAT assay methods, followed by a systematic discussion of TAG biosynthesis and the properties and physiological role of DGATs. Thereafter, the review discusses the three-dimensional structure and insights into mechanism of action of human DGAT1, and the modeled DGAT1 from Brassica napus. The review then examines metabolic engineering strategies involving manipulation of DGAT, followed by a discussion of its therapeutic applications. DGAT in relation to improvement of livestock traits is also discussed along with DGATs in various other eukaryotic organisms.
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Affiliation(s)
- Guanqun Chen
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, Alberta T6H 2P5, Canada.
| | - John L Harwood
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - M Joanne Lemieux
- Department of Biochemistry, University of Alberta, Membrane Protein Disease Research Group, Edmonton T6G 2H7, Canada
| | - Scot J Stone
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada.
| | - Randall J Weselake
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, Alberta T6H 2P5, Canada
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10
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Ma Y, Fei Y, Han X, Liu G, Fang J. Lactobacillus plantarum Alleviates Obesity by Altering the Composition of the Gut Microbiota in High-Fat Diet-Fed Mice. Front Nutr 2022; 9:947367. [PMID: 35845812 PMCID: PMC9280677 DOI: 10.3389/fnut.2022.947367] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 06/10/2022] [Indexed: 01/02/2023] Open
Abstract
Metabolic disorders and intestinal flora imbalance usually accompany obesity. Due to its diverse biological activities, Lactobacillus plantarum is widely used to alleviate various diseases as a probiotic. Here, we show that L. plantarum can reduce the body weight of mice fed high-fat diets, reduce fat accumulation, and enhance mice glucose tolerance. Our results show that L. plantarum can significantly reduce the expression of DGAT1 and DGAT2, increase the expression of Cpt1a, and promote the process of lipid metabolism. Further data show that L. plantarum can increase the SCFA content in the colon and reverse the intestinal flora disorder caused by HFD, increase the abundance of Bacteroides, and Bifidobacteriales, and reduce the abundance of Firmicutes and Clostridiales. Finally, through Pearson correlation analysis, we found that Bacteroides and SCFAs are positively correlated, while Clostridiales are negatively correlated with SCFAs. Therefore, we believe that L. plantarum can regulate the structure of the intestinal microbial community, increase the production of SCFAs and thus regulate lipid metabolism.
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11
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Sar1 Affects the Localization of Perilipin 2 to Lipid Droplets. Int J Mol Sci 2022; 23:ijms23126366. [PMID: 35742827 PMCID: PMC9223735 DOI: 10.3390/ijms23126366] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 06/03/2022] [Accepted: 06/03/2022] [Indexed: 02/05/2023] Open
Abstract
Lipid droplets (LDs) are intracellular organelles that are ubiquitous in many types of cells. The LD core consists of triacylglycerols (TGs) surrounded by a phospholipid monolayer and surface proteins such as perilipin 2 (PLIN2). Although TGs accumulate in the phospholipid bilayer of the endoplasmic reticulum (ER) and subsequently nascent LDs buds from ER, the mechanism by which LD proteins are transported to LD particles is not fully understood. Sar1 is a GTPase known as a regulator of coat protein complex Ⅱ (COPⅡ) vesicle budding, and its role in LD formation was investigated in this study. HuH7 human hepatoma cells were infected with adenoviral particles containing genes coding GFP fused with wild-type Sar1 (Sar1 WT) or a GTPase mutant form (Sar1 H79G). When HuH7 cells were treated with oleic acid, Sar1 WT formed a ring-like structure around the LDs. The transient expression of Sar1 did not significantly alter the levels of TG and PLIN2 in the cells. However, the localization of PLIN2 to the LDs decreased in the cells expressing Sar1 H79G. Furthermore, the effects of Sar1 on PLIN2 localization to the LDs were verified by the suppression of endogenous Sar1 using the short hairpin RNA technique. In conclusion, it was found that Sar1 has some roles in the intracellular distribution of PLIN2 to LDs in liver cells.
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12
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Updates on novel pharmacotherapeutics for the treatment of nonalcoholic steatohepatitis. Acta Pharmacol Sin 2022; 43:1180-1190. [PMID: 35190696 PMCID: PMC9061746 DOI: 10.1038/s41401-022-00860-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 01/03/2022] [Indexed: 12/14/2022] Open
Abstract
Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease (NAFLD), characterized with hepatocellular steatosis, ballooning, lobular inflammation, fibrotic progression, and insulin resistance. NASH may progress to cirrhosis and hepatocellular carcinoma (HCC), which are the major indications for liver transplantation and the causes for mortality. Thus far, there are no approved pharmacotherapeutics for the treatment of NASH. Given the complexity of NASH pathogenesis at multifaceted aspects, such as lipotoxicity, inflammation, insulin resistance, mitochondrial dysfunction and fibrotic progression, pharmacotherapeutics under investigation target different key pathogenic pathways to gain either the resolution of steatohepatitis or regression of fibrosis, ideally both. Varieties of pharmacologic candidates have been tested in clinical trials and have generated some positive results. On the other hand, recent failure or termination of a few phase II and III trials is disappointing in this field. In face to growing challenges in pharmaceutical development, this review intends to summarize the latest data of new medications which have completed phase II or III trials, and discuss the rationale and preliminary results of several combinatory options. It is anticipated that with improved understanding of NASH pathogenesis and critical endpoints, efficient pharmacotherapeutics will be available for the treatment of NASH with an acceptable safety profile.
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13
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Shi H, Zhou X, He X, Wang R, Zhou W. Camellia oil Enhances Plasma Antioxidant Metabolism and Improves Plasma Lipid Metabolism in High-fat Diet-fed Rats. Nat Prod Commun 2022. [DOI: 10.1177/1934578x221081368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Living on a high-fat, high-calorie, and high-protein diet for a long period may compromise human immunity due to the long-term accumulation of free radicals and plasma lipids. The antioxidant and lipid-lowering compounds (ie polyphenols and vitamin E) in Camellia oil help to decrease the risk of numerous ailments, including cardiovascular disease (CVD), and obesity. The aims of this study were to study the hypolipidemic and antioxidant effects of Camellia oil in high-fat-fed rats and to promote the high-value use of camellia resources. The high-fat-fed rats were administrated with 2.5, 7.5, and 15 mL/kg BW Camellia oil (Camellia oil group), and 10 mg/kg BW atorvastatin (atorvastatin group), respectively, and compared with a model group (only fed with high fat) and a control group (fed with basal diet). Several parameters were measured, including (1) body weight (BW), liver-to-BW ratio; (2) plasma total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C); and (3) alanine aminotransferase (ALT), alanine aminotransferase (AST), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activity, model driven architecture (MDA) content, lipid metabolism-related genes, and antioxidant-related genes in liver tissue. Compared with the model group, the high-fat-fed rats in the Camellia oil and atorvastatin group had significantly lower BW and liver-to-BW ratio ( P < .01), plasma TC, TG, and LDL-C levels and ALT and AST activities, but higher HDL-C levels. The relative expressions of ACAT1, DGAT2, FAS, and SREBP genes were significantly reduced in the Camellia oil and atorvastatin groups, while the relative expressions of LCAT, UCP2, MCD, and CPT-1 genes were significantly increased. The rats in the Camellia oil group showed significantly higher SOD and GSH-Px activities, significantly lower MDA content, and significantly higher relative expression of antioxidant genes (eg SOD1, GPx1, CAT, and Gclm). Thus, atorvastatin and Camellia oil exhibited significant hypolipidemic and antioxidant effects, which were better at a dose of 7.5 mL/kg (BW) of Camellia oil. Therefore, Camellia oil becomes a potential new natural resource for future research and development of antioxidant and hypolipidemic drugs, nutraceuticals, and additives.
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Affiliation(s)
- Hao Shi
- Central South University of Forestry and Technology, Changsha, People’s Republic of China
- Hunan Applied technology University, Changde, People’s Republic of China
| | | | - Xiaoe He
- Hunan Applied technology University, Changde, People’s Republic of China
| | - Rencai Wang
- Hunan Applied technology University, Changde, People’s Republic of China
- Hunan Agricultural University, Changsha, People’s Republic of China
| | - Wenhua Zhou
- Central South University of Forestry and Technology, Changsha, People’s Republic of China
- Hunan Applied technology University, Changde, People’s Republic of China
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14
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Yenilmez B, Wetoska N, Kelly M, Echeverria D, Min K, Lifshitz L, Alterman JF, Hassler MR, Hildebrand S, DiMarzio C, McHugh N, Vangjeli L, Sousa J, Pan M, Han X, Brehm MA, Khvorova A, Czech MP. An RNAi therapeutic targeting hepatic DGAT2 in a genetically obese mouse model of nonalcoholic steatohepatitis. Mol Ther 2022; 30:1329-1342. [PMID: 34774753 PMCID: PMC8899521 DOI: 10.1016/j.ymthe.2021.11.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 10/31/2021] [Accepted: 11/05/2021] [Indexed: 10/19/2022] Open
Abstract
Nonalcoholic steatohepatitis (NASH) is a severe liver disorder characterized by triglyceride accumulation, severe inflammation, and fibrosis. With the recent increase in prevalence, NASH is now the leading cause of liver transplant, with no approved therapeutics available. Although the exact molecular mechanism of NASH progression is not well understood, a widely held hypothesis is that fat accumulation is the primary driver of the disease. Therefore, diacylglycerol O-acyltransferase 2 (DGAT2), a key enzyme in triglyceride synthesis, has been explored as a NASH target. RNAi-based therapeutics is revolutionizing the treatment of liver diseases, with recent chemical advances supporting long-term gene silencing with single subcutaneous administration. Here, we identified a hyper-functional, fully chemically stabilized GalNAc-conjugated small interfering RNA (siRNA) targeting DGAT2 (Dgat2-1473) that, upon injection, elicits up to 3 months of DGAT2 silencing (>80%-90%, p < 0.0001) in wild-type and NSG-PiZ "humanized" mice. Using an obesity-driven mouse model of NASH (ob/ob-GAN), Dgat2-1473 administration prevents and reverses triglyceride accumulation (>85%, p < 0.0001) without increased accumulation of diglycerides, resulting in significant improvement of the fatty liver phenotype. However, surprisingly, the reduction in liver fat did not translate into a similar impact on inflammation and fibrosis. Thus, while Dgat2-1473 is a practical, long-lasting silencing agent for potential therapeutic attenuation of liver steatosis, combinatorial targeting of a second pathway may be necessary for therapeutic efficacy against NASH.
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Affiliation(s)
- Batuhan Yenilmez
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA
| | - Nicole Wetoska
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA
| | - Mark Kelly
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA
| | - Dimas Echeverria
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA; RNA Therapeutics Institute, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA
| | - Kyounghee Min
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA
| | - Lawrence Lifshitz
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA
| | - Julia F Alterman
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA; RNA Therapeutics Institute, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA
| | - Matthew R Hassler
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA; RNA Therapeutics Institute, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA
| | - Samuel Hildebrand
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA; RNA Therapeutics Institute, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA
| | - Chloe DiMarzio
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA
| | - Nicholas McHugh
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA; RNA Therapeutics Institute, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA
| | - Lorenc Vangjeli
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA; RNA Therapeutics Institute, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA
| | - Jacquelyn Sousa
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA; RNA Therapeutics Institute, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA
| | - Meixia Pan
- Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Xianlin Han
- Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Michael A Brehm
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA
| | - Anastasia Khvorova
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA; RNA Therapeutics Institute, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA.
| | - Michael P Czech
- Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street Biotech Two, Suite 100, Worcester, MA 01605, USA.
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15
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Therapeutic RNA-silencing oligonucleotides in metabolic diseases. Nat Rev Drug Discov 2022; 21:417-439. [PMID: 35210608 DOI: 10.1038/s41573-022-00407-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2022] [Indexed: 12/14/2022]
Abstract
Recent years have seen unprecedented activity in the development of RNA-silencing oligonucleotide therapeutics for metabolic diseases. Improved oligonucleotide design and optimization of synthetic nucleic acid chemistry, in combination with the development of highly selective and efficient conjugate delivery technology platforms, have established and validated oligonucleotides as a new class of drugs. To date, there are five marketed oligonucleotide therapies, with many more in clinical studies, for both rare and common liver-driven metabolic diseases. Here, we provide an overview of recent developments in the field of oligonucleotide therapeutics in metabolism, review past and current clinical trials, and discuss ongoing challenges and possible future developments.
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16
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Yang W, Wang S, Loor JJ, Lopes MG, Zhao Y, Ma X, Li M, Zhang B, Xu C. Role of diacylglycerol O-acyltransferase (DGAT) isoforms in bovine hepatic fatty acid metabolism. J Dairy Sci 2022; 105:3588-3600. [PMID: 35181144 DOI: 10.3168/jds.2021-21140] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 12/23/2021] [Indexed: 12/17/2022]
Abstract
Fatty acid accumulation in hepatocytes induced by high concentrations of fatty acids due to lipolysis and the associated oxidative damage they cause occur most frequently after calving. Because of their role in esterification of fatty acids, diacylglycerol acyltransferase isoforms (DGAT1 and DGAT2) could play a role in the susceptibility of dairy cows to develop fatty liver. To gain mechanistic insights, we performed in vivo and in vitro analyses using liver biopsies or isolated primary hepatocytes. The in vivo study (n = 5 cows/group) involved healthy cows [average liver triacylglycerol (TAG) = 0.78%; 0.58 to 0.93%, ratio of triglyceride weight to wet liver weight] or cows diagnosed with fatty liver (average TAG = 7.60%; 5.31 to 10.54%). In vitro, hepatocytes isolated from 3 healthy female calves (1 d old, 44 to 53 kg) were challenged with (fatty acids) or without (control) a 1.2 mM mixture of fatty acids in an attempt to induce metabolic stress. Furthermore, hepatocytes were treated with DGAT1 inhibitor or DGAT2 inhibitor for 2 h followed by a challenge with (DGAT1 inhibitor + fatty acids or DGAT2 inhibitor + fatty acids) or without (DGAT1 inhibitor or DGAT2 inhibitor) the 1.2 mM mixture of fatty acids for 12 h. Data analysis of liver biopsies was compared using a 2-tailed unpaired Student's t-test. Data from calf hepatocyte treatment comparisons were assessed by one-way ANOVA, and multiplicity for each experiment was adjusted by the Holm's procedure. Data indicated that both fatty liver and in vitro challenge with fatty acids were associated with greater mRNA and protein abundance of SREBF1, FASN, DGAT1, and DGAT2. In contrast, mRNA and protein abundance of CPT1A and very low-density lipoprotein synthesis-related proteins MTTP and APOB were markedly lower. However, compared with fatty acid challenge alone, DGAT1 inhibitor + fatty acids led to greater mRNA and protein abundance of CPT1A and APOB, and greater mRNA abundance of SREBF1 and MTTP. Furthermore, this treatment led to lower mRNA abundance of FASN and DGAT2 and TAG concentrations. Compared with fatty acid challenge alone, DGAT2 inhibitor + fatty acids led to greater mRNA and protein abundance of CPT1A, MTTP, and APOB, and lower mRNA and protein abundance of SREBF1 and FASN. In addition, compared with control and fatty acids, there was greater protein abundance of GRP78 and PERK in both DGAT1 and DGAT2 inhibitor with or without fatty acids. Furthermore, compared with control and fatty acids, reactive oxygen species concentrations in the DGAT1 inhibitor with or without fatty acid group was greater. Overall, data suggested that DGAT1 is particularly relevant in the context of hepatocyte TAG synthesis from exogenous fatty acids. Disruption of both DGAT1 and DGAT2 altered lipid homeostasis, channeling fatty acids toward oxidation and generation of reactive oxygen species. Both DGAT isoforms play a role in promoting fatty acid storage into TAG and lipid droplets to protect hepatocytes from oxidative damage.
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Affiliation(s)
- Wei Yang
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163319, China
| | - Shuang Wang
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163319, China
| | - Juan J Loor
- Mammalian NutriPhysioGenomics, Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801
| | - Matheus G Lopes
- Mammalian NutriPhysioGenomics, Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801
| | - Yingying Zhao
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163319, China
| | - Xinru Ma
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163319, China
| | - Ming Li
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163319, China
| | - Bingbing Zhang
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University, Daqing 163319, China
| | - Chuang Xu
- Heilongjiang Provincial Key Laboratory of Prevention and Control of Bovine Diseases, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163319, China.
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17
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Chu X, Raju RP. Regulation of NAD + metabolism in aging and disease. Metabolism 2022; 126:154923. [PMID: 34743990 PMCID: PMC8649045 DOI: 10.1016/j.metabol.2021.154923] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 10/17/2021] [Accepted: 10/25/2021] [Indexed: 01/03/2023]
Abstract
More than a century after discovering NAD+, information is still evolving on the role of this molecule in health and diseases. The biological functions of NAD+ and NAD+ precursors encompass pathways in cellular energetics, inflammation, metabolism, and cell survival. Several metabolic and neurological diseases exhibit reduced tissue NAD+ levels. Significantly reduced levels of NAD+ are also associated with aging, and enhancing NAD+ levels improved healthspan and lifespan in animal models. Recent studies suggest a causal link between senescence, age-associated reduction in tissue NAD+ and enzymatic degradation of NAD+. Furthermore, the discovery of transporters and receptors involved in NAD+ precursor (nicotinic acid, or niacin, nicotinamide, and nicotinamide riboside) metabolism allowed for a better understanding of their role in cellular homeostasis including signaling functions that are independent of their functions in redox reactions. We also review studies that demonstrate that the functional effect of niacin is partially due to the activation of its cell surface receptor, GPR109a. Based on the recent progress in understanding the mechanism and function of NAD+ and NAD+ precursors in cell metabolism, new strategies are evolving to exploit these molecules' pharmacological potential in the maintenance of metabolic balance.
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Affiliation(s)
- Xiaogang Chu
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA 30912, United States of America
| | - Raghavan Pillai Raju
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA 30912, United States of America.
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18
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Satapati S, Downes DP, Metzger D, Shankaran H, Talukdar S, Zhou Y, Ren Z, Chen M, Lim YH, Hatcher NG, Wen X, Sheth PR, McLaren DG, Previs SF. Using measures of metabolic flux to align screening and clinical development: Avoiding pitfalls to enable translational studies. SLAS DISCOVERY : ADVANCING LIFE SCIENCES R & D 2022; 27:20-28. [PMID: 35058172 DOI: 10.1016/j.slasd.2021.10.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Screening campaigns, especially those aimed at modulating enzyme activity, often rely on measuring substrate→product conversions. Unfortunately, the presence of endogenous substrates and/or products can limit one's ability to measure conversions. As well, coupled detection systems, often used to facilitate optical readouts, are subject to interference. Stable isotope labeled substrates can overcome background contamination and yield a direct readout of enzyme activity. Not only can isotope kinetic assays enable early screening, but they can also be used to follow hit progression in translational (pre)clinical studies. Herein, we consider a case study surrounding lipid biology to exemplify how metabolic flux analyses can connect stages of drug development, caveats are highlighted to ensure reliable data interpretations. For example, when measuring enzyme activity in early biochemical screening it may be enough to quantify the formation of a labeled product. In contrast, cell-based and in vivo studies must account for variable exposure to a labeled substrate (or precursor) which occurs via tracer dilution and/or isotopic exchange. Strategies are discussed to correct for these complications. We believe that measures of metabolic flux can help connect structure-activity relationships with pharmacodynamic mechanisms of action and determine whether mechanistically differentiated biophysical interactions lead to physiologically relevant outcomes. Adoption of this logic may allow research programs to (i) build a critical bridge between primary screening and (pre)clinical development, (ii) elucidate biology in parallel with screening and (iii) suggest a strategy aimed at in vivo biomarker development.
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Affiliation(s)
- Santhosh Satapati
- Merck & Co., Inc, 213 E. Grand Ave, South San Francisco, CA, 94080, USA
| | - Daniel P Downes
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, NJ, 07033, USA
| | - Daniel Metzger
- Merck & Co., Inc, 213 E. Grand Ave, South San Francisco, CA, 94080, USA
| | - Harish Shankaran
- Merck & Co., Inc, 213 E. Grand Ave, South San Francisco, CA, 94080, USA
| | - Saswata Talukdar
- Merck & Co., Inc, 213 E. Grand Ave, South San Francisco, CA, 94080, USA
| | - Yingjiang Zhou
- Merck & Co., Inc, 213 E. Grand Ave, South San Francisco, CA, 94080, USA
| | - Zhao Ren
- Merck & Co., Inc, 213 E. Grand Ave, South San Francisco, CA, 94080, USA
| | - Michelle Chen
- Merck & Co., Inc, 213 E. Grand Ave, South San Francisco, CA, 94080, USA
| | - Yeon-Hee Lim
- Merck & Co., Inc, 213 E. Grand Ave, South San Francisco, CA, 94080, USA
| | - Nathan G Hatcher
- Merck & Co., Inc, 770 Sumneytown Pike, West Point, PA, 19486, USA
| | - Xiujuan Wen
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, NJ, 07033, USA
| | - Payal R Sheth
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, NJ, 07033, USA
| | - David G McLaren
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, NJ, 07033, USA
| | - Stephen F Previs
- Merck & Co., Inc, 2000 Galloping Hill Rd, Kenilworth, NJ, 07033, USA.
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19
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Yuan S, Yan B, Cao J, Ye ZW, Liang R, Tang K, Luo C, Cai J, Chu H, Chung TWH, To KKW, Hung IFN, Jin DY, Chan JFW, Yuen KY. SARS-CoV-2 exploits host DGAT and ADRP for efficient replication. Cell Discov 2021; 7:100. [PMID: 34702802 PMCID: PMC8548329 DOI: 10.1038/s41421-021-00338-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 09/03/2021] [Indexed: 01/20/2023] Open
Abstract
Coronavirus Disease 2019 (COVID-19) is predominantly a respiratory tract infection that significantly rewires the host metabolism. Here, we monitored a cohort of COVID-19 patients’ plasma lipidome over the disease course and identified triacylglycerol (TG) as the dominant lipid class present in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced metabolic dysregulation. In particular, we pinpointed the lipid droplet (LD)-formation enzyme diacylglycerol acyltransferase (DGAT) and the LD stabilizer adipocyte differentiation-related protein (ADRP) to be essential host factors for SARS-CoV-2 replication. Mechanistically, viral nucleo capsid protein drives DGAT1/2 gene expression to facilitate LD formation and associates with ADRP on the LD surface to complete the viral replication cycle. DGAT gene depletion reduces SARS-CoV-2 protein synthesis without compromising viral genome replication/transcription. Importantly, a cheap and orally available DGAT inhibitor, xanthohumol, was found to suppress SARS-CoV-2 replication and the associated pulmonary inflammation in a hamster model. Our findings not only uncovered the mechanistic role of SARS-CoV-2 nucleocapsid protein to exploit LDs-oriented network for heightened metabolic demand, but also the potential to target the LDs-synthetase DGAT and LDs-stabilizer ADRP for COVID-19 treatment.
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Affiliation(s)
- Shuofeng Yuan
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China. .,Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, Guangdong Province, China.
| | - Bingpeng Yan
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Jianli Cao
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Zi-Wei Ye
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Ronghui Liang
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Kaiming Tang
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Cuiting Luo
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Jianpiao Cai
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Hin Chu
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China.,Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, Guangdong Province, China
| | - Tom Wai-Hing Chung
- Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, Guangdong Province, China
| | - Kelvin Kai-Wang To
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China.,Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, Guangdong Province, China.,Department of Microbiology, Queen Mary Hospital, Pokfulam, Hong Kong Special Administrative Region, China
| | - Ivan Fan-Ngai Hung
- Department of Microbiology, Queen Mary Hospital, Pokfulam, Hong Kong Special Administrative Region, China.,Department of Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Dong-Yan Jin
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Jasper Fuk-Woo Chan
- Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, Guangdong Province, China. .,Department of Microbiology, Queen Mary Hospital, Pokfulam, Hong Kong Special Administrative Region, China. .,Academician workstation of Hainan Province of Hainan Medical University, and Hainan Medical University-The University of Hong Kong Joint Laboraotry of Tropical Infectious Diseasees, The University of Hong Kong, Pokfulam, Hong Kong Speical Administrative Region, China.
| | - Kwok-Yung Yuen
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China. .,Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, Guangdong Province, China. .,Department of Microbiology, Queen Mary Hospital, Pokfulam, Hong Kong Special Administrative Region, China. .,Academician workstation of Hainan Province of Hainan Medical University, and Hainan Medical University-The University of Hong Kong Joint Laboraotry of Tropical Infectious Diseasees, The University of Hong Kong, Pokfulam, Hong Kong Speical Administrative Region, China.
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20
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Govatati S, Pichavaram P, Mani AM, Kumar R, Sharma D, Dienel A, Meena S, Puchowicz MA, Park EA, Rao GN. Novel role of xanthine oxidase-dependent H 2O 2 production in 12/15-lipoxygenase-mediated de novo lipogenesis, triglyceride biosynthesis and weight gain. Redox Biol 2021; 47:102163. [PMID: 34655995 PMCID: PMC8577505 DOI: 10.1016/j.redox.2021.102163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/07/2021] [Accepted: 10/07/2021] [Indexed: 11/16/2022] Open
Abstract
12/15-lipoxygenase (12/15-LOX) plays an essential role in oxidative conversion of polyunsaturated fatty acids into various bioactive lipid molecules. Although 12/15-LOX's role in the pathophysiology of various human diseases has been well studied, its role in weight gain is controversial and poorly clarified. Here, we demonstrated the role of 12/15-LOX in high-fat diet (HFD)-induced weight gain in a mouse model. We found that 12/15-LOX mediates HFD-induced de novo lipogenesis (DNL), triglyceride (TG) biosynthesis and the transport of TGs from the liver to adipose tissue leading to white adipose tissue (WAT) expansion and weight gain via xanthine oxidase (XO)-dependent production of H2O2. 12/15-LOX deficiency leads to cullin2-mediated ubiquitination and degradation of XO, thereby suppressing H2O2 production, DNL and TG biosynthesis resulting in reduced WAT expansion and weight gain. These findings infer that manipulation of 12/15-LOX metabolism may manifest a potential therapeutic target for weight gain and obesity. 12/15-LOX-12(S)-HETE axis via activation of CREB-Egr1 enhances TG biosynthesis. 12/15-LOX-12(S)-HETE axis via activation of SREBP1c triggers DNL. H2O2 mediates 12/15-LOX-12(S)-HETE axis-induced DNL and TG biosynthesis. 12/15-LOX via TG biosynthesis leads to WAT expansion and body weight gain. Downstream to 12/15-LOX, H2O2-mediates WAT expansion and body weight gain.
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Affiliation(s)
- Suresh Govatati
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Prahalathan Pichavaram
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Arul M Mani
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Raj Kumar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Deepti Sharma
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Ari Dienel
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Sunita Meena
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Michelle A Puchowicz
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Edwards A Park
- Department of Pharmacology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA.
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21
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McCarron S, Bathon B, Conlon DM, Abbey D, Rader DJ, Gawronski K, Brown CD, Olthoff KM, Shaked A, Raabe TD. Functional Characterization of Organoids Derived From Irreversibly Damaged Liver of Patients With NASH. Hepatology 2021; 74:1825-1844. [PMID: 33901295 DOI: 10.1002/hep.31857] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 03/01/2021] [Accepted: 03/21/2021] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIMS NASH will soon become the leading cause of liver transplantation in the United States and is also associated with increased COVID-19 mortality. Currently, there are no Food and Drug Administration-approved drugs available that slow NASH progression or address NASH liver involvement in COVID-19. Because animal models cannot fully recapitulate human NASH, we hypothesized that stem cells isolated directly from end-stage liver from patients with NASH may address current knowledge gaps in human NASH pathology. APPROACH AND RESULTS We devised methods that allow the derivation, proliferation, hepatic differentiation, and extensive characterization of bipotent ductal organoids from irreversibly damaged liver from patients with NASH. The transcriptomes of organoids derived from NASH liver, but not healthy liver, show significant up-regulation of proinflammatory and cytochrome p450-related pathways, as well as of known liver fibrosis and tumor markers, with the degree of up-regulation being patient-specific. Functionally, NASH liver organoids exhibit reduced passaging/growth capacity and hallmarks of NASH liver, including decreased albumin production, increased free fatty acid-induced lipid accumulation, increased sensitivity to apoptotic stimuli, and increased cytochrome P450 metabolism. After hepatic differentiation, NASH liver organoids exhibit reduced ability to dedifferentiate back to the biliary state, consistent with the known reduced regenerative ability of NASH livers. Intriguingly, NASH liver organoids also show strongly increased permissiveness to severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) vesicular stomatitis pseudovirus as well as up-regulation of ubiquitin D, a known inhibitor of the antiviral interferon host response. CONCLUSION Expansion of primary liver stem cells/organoids derived directly from irreversibly damaged liver from patients with NASH opens up experimental avenues for personalized disease modeling and drug development that has the potential to slow human NASH progression and to counteract NASH-related SARS-CoV-2 effects.
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Affiliation(s)
- Sarah McCarron
- Department of Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Brooke Bathon
- Department of Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Donna M Conlon
- Department of Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Deepti Abbey
- Department of Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Daniel J Rader
- Department of Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Katerina Gawronski
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Christopher D Brown
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Kim M Olthoff
- Department of Surgery, Division of Transplant Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Abraham Shaked
- Department of Surgery, Division of Transplant Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Tobias D Raabe
- Department of Medicine, Division of Translational Medicine and Human Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
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22
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Heeren J, Scheja L. Metabolic-associated fatty liver disease and lipoprotein metabolism. Mol Metab 2021; 50:101238. [PMID: 33892169 PMCID: PMC8324684 DOI: 10.1016/j.molmet.2021.101238] [Citation(s) in RCA: 210] [Impact Index Per Article: 70.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 04/01/2021] [Accepted: 04/15/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Non-alcoholic fatty liver disease, or as recently proposed 'metabolic-associated fatty liver disease' (MAFLD), is characterized by pathological accumulation of triglycerides and other lipids in hepatocytes. This common disease can progress from simple steatosis to steatohepatitis, and eventually end-stage liver diseases. MAFLD is closely related to disturbances in systemic energy metabolism, including insulin resistance and atherogenic dyslipidemia. SCOPE OF REVIEW The liver is the central organ in lipid metabolism by secreting very low density lipoproteins (VLDL) and, on the other hand, by internalizing fatty acids and lipoproteins. This review article discusses recent research addressing hepatic lipid synthesis, VLDL production, and lipoprotein internalization as well as the lipid exchange between adipose tissue and the liver in the context of MAFLD. MAJOR CONCLUSIONS Liver steatosis in MAFLD is triggered by excessive hepatic triglyceride synthesis utilizing fatty acids derived from white adipose tissue (WAT), de novo lipogenesis (DNL) and endocytosed remnants of triglyceride-rich lipoproteins. In consequence of high hepatic lipid content, VLDL secretion is enhanced, which is the primary cause of complex dyslipidemia typical for subjects with MAFLD. Interventions reducing VLDL secretory capacity attenuate dyslipidemia while they exacerbate MAFLD, indicating that the balance of lipid storage versus secretion in hepatocytes is a critical parameter determining disease outcome. Proof of concept studies have shown that promoting lipid storage and energy combustion in adipose tissues reduces hepatic lipid load and thus ameliorates MAFLD. Moreover, hepatocellular triglyceride synthesis from DNL and WAT-derived fatty acids can be targeted to treat MAFLD. However, more research is needed to understand how individual transporters, enzymes, and their isoforms affect steatosis and dyslipidemia in vivo, and whether these two aspects of MAFLD can be selectively treated. Processing of cholesterol-enriched lipoproteins appears less important for steatosis. It may, however, modulate inflammation and consequently MAFLD progression.
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Affiliation(s)
- Joerg Heeren
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| | - Ludger Scheja
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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23
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Caputo M, Kurhe Y, Kumari S, Cansby E, Amrutkar M, Scandalis E, Booten SL, Ståhlman M, Borén J, Marschall HU, Aghajan M, Mahlapuu M. Silencing of STE20-type kinase MST3 in mice with antisense oligonucleotide treatment ameliorates diet-induced nonalcoholic fatty liver disease. FASEB J 2021; 35:e21567. [PMID: 33891332 DOI: 10.1096/fj.202002671rr] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 03/17/2021] [Accepted: 03/17/2021] [Indexed: 12/15/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is emerging as a leading cause of chronic liver disease worldwide. Despite intensive nonclinical and clinical research in this field, no specific pharmacological therapy is currently approved to treat NAFLD, which has been recognized as one of the major unmet medical needs of the 21st century. Our recent studies have identified STE20-type kinase MST3, which localizes to intracellular lipid droplets, as a critical regulator of ectopic fat accumulation in human hepatocytes. Here, we explored whether treatment with Mst3-targeting antisense oligonucleotides (ASOs) can promote hepatic lipid clearance and mitigate NAFLD progression in mice in the context of obesity. We found that administration of Mst3-targeting ASOs in mice effectively ameliorated the full spectrum of high-fat diet-induced NAFLD including liver steatosis, inflammation, fibrosis, and hepatocellular damage. Mechanistically, Mst3 ASOs suppressed lipogenic gene expression, as well as acetyl-CoA carboxylase (ACC) protein abundance, and substantially reduced lipotoxicity-mediated oxidative and endoplasmic reticulum stress in the livers of obese mice. Furthermore, we found that MST3 protein levels correlated positively with the severity of NAFLD in human liver biopsies. In summary, this study provides the first in vivo evidence that antagonizing MST3 signaling is sufficient to mitigate NAFLD progression in conditions of excess dietary fuels and warrants future investigations to assess whether MST3 inhibitors may provide a new strategy for the treatment of patients with NAFLD.
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Affiliation(s)
- Mara Caputo
- Department of Chemistry and Molecular Biology, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Yeshwant Kurhe
- Department of Chemistry and Molecular Biology, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Sima Kumari
- Department of Chemistry and Molecular Biology, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Emmelie Cansby
- Department of Chemistry and Molecular Biology, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Manoj Amrutkar
- Department of Hepato-Pancreato-Biliary Surgery, Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | | | | | - Marcus Ståhlman
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Jan Borén
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Hanns-Ulrich Marschall
- Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | | | - Margit Mahlapuu
- Department of Chemistry and Molecular Biology, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
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24
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Liu Z, Liu J, Zhang T, Li L, Zhang S, Jia H, Xia Y, Shi M, Zhang J, Yue S, Chen X, Yu J. Distinct BTK inhibitors differentially induce apoptosis but similarly suppress chemotaxis and lipid accumulation in mantle cell lymphoma. BMC Cancer 2021; 21:732. [PMID: 34174847 PMCID: PMC8235860 DOI: 10.1186/s12885-021-08475-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 06/04/2021] [Indexed: 11/10/2022] Open
Abstract
Background The more selective second-generation BTK inhibitors (BTKi) Acalabrutinib and Zanubrutinib and the first-generation BTKi Ibrutinib are highlighted by their clinical effectiveness in mantle cell lymphoma (MCL), however, similarities and differences of their biological and molecular effects on anti-survival of MCL cells induced by these BTKi with distinct binding selectivity against BTK remain largely unknown. Methods AlamarBlue assays were performed to define cytotoxicity of BTKi against MCL cells, Jeko-1 and Mino. Cleaved PARP and caspase-3 levels were examined by immunoblot analysis to study BTKi-induced apoptotic effects. Biological effects of BTKi on MCL-cell chemotaxis and lipid droplet (LD) accumulation were examined in Jeko-1, Mino and primary MCL cells via Transwell and Stimulated Raman scattering imaging analysis respectively. Enzyme-linked immunoassays were used to determine CCL3 and CCL4 levels in MCL-cell culture supernatants. RNA-seq analyses identified BTKi targets which were validated by quantitative RT-PCR (qRT-PCR) and immunoblot analysis. Results Acalabrutinib and Zanubrutinib induced moderate apoptosis in Ibrutinib high-sensitive JeKo-1 cells and Ibrutinib low-sensitive Mino cells, which was accompanied by cleaved PARP and caspase-3. Such effects might be caused by the stronger ability of Ibrutinib to upregulate the expression of pro-apoptotic genes, such as HRK, GADD45A, and ATM, in JeKo-1 cells than in Mino cells, and the expression of such apoptotic genes was slightly changed by Acalabrutinib and Zanubrutinib in both JeKo-1 and Mino cells. Further, Acalabrutinib, Zanubrutinib and Ibrutinib reduced MCL-cell chemotaxis with similar efficiency, due to their similar abilities to downmodulate chemokines, such as CCL3 and CCL4. Also, these three BTKi similarly suppressed MCL-cell LD accumulation via downregulating lipogenic factors, DGAT2, SCD, ENPP2 and ACACA without significant differences. Conclusion BTKi demonstrated differential capacities to induce MCL-cell apoptosis due to their distinct capabilities to regulate the expression of apoptosis-related genes, and similar biological and molecular inhibitory effects on MCL-cell chemotaxis and LD accumulation. Supplementary Information The online version contains supplementary material available at 10.1186/s12885-021-08475-3.
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Affiliation(s)
- Zhuojun Liu
- Interdisciplinary Institute of Cancer Diagnosis and Treatment, Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beihang University, Beijing, 100083, China.,School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Jia Liu
- Interdisciplinary Institute of Cancer Diagnosis and Treatment, Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beihang University, Beijing, 100083, China.,School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Tianming Zhang
- Interdisciplinary Institute of Cancer Diagnosis and Treatment, Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beihang University, Beijing, 100083, China.,School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Lin Li
- Interdisciplinary Institute of Cancer Diagnosis and Treatment, Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beihang University, Beijing, 100083, China.,School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Shuo Zhang
- School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Hao Jia
- School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Yuanshi Xia
- School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Mingxia Shi
- Department of Hematology, the First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Jing Zhang
- Interdisciplinary Institute of Cancer Diagnosis and Treatment, Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beihang University, Beijing, 100083, China.,School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Shuhua Yue
- School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Xiaofang Chen
- School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China.
| | - Jian Yu
- Interdisciplinary Institute of Cancer Diagnosis and Treatment, Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beihang University, Beijing, 100083, China. .,School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China.
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25
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Wen X, Liu C, Ghislain L, Tovar K, Shah V, Stout SJ, Cifelli S, Satapati S, O’Donnell G, Sheth PR, Wildey MJ, Datwani SS, Covey TR, Bateman KP, McLaren DG. Direct Analysis from Phase-Separated Liquid Samples using ADE-OPI-MS: Applicability to High-Throughput Screening for Inhibitors of Diacylglycerol Acyltransferase 2. Anal Chem 2021; 93:6071-6079. [DOI: 10.1021/acs.analchem.0c04312] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Xiujuan Wen
- Merck & Company, Incorporated, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Chang Liu
- SCIEX, 71 Four Valley Drive, Concord, Ontario L4K 4 V8, Canada
| | - Lucien Ghislain
- Beckman Coulter Life Sciences Incorporated, 170 Rose Orchard Way, San Jose, California 95134, United States
| | - Kiersten Tovar
- Merck & Company, Incorporated, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Vinit Shah
- Merck & Company, Incorporated, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Steven J. Stout
- Merck & Company, Incorporated, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Steven Cifelli
- Merck & Company, Incorporated, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Santhosh Satapati
- Merck & Company, Incorporated, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Gregory O’Donnell
- Merck & Company, Incorporated, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Payal R. Sheth
- Merck & Company, Incorporated, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Mary Jo Wildey
- Merck & Company, Incorporated, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - Sammy S. Datwani
- Beckman Coulter Life Sciences Incorporated, 170 Rose Orchard Way, San Jose, California 95134, United States
| | - Thomas R. Covey
- SCIEX, 71 Four Valley Drive, Concord, Ontario L4K 4 V8, Canada
| | - Kevin P. Bateman
- Merck & Company, Incorporated, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
| | - David G. McLaren
- Merck & Company, Incorporated, 2000 Galloping Hill Road, Kenilworth, New Jersey 07033, United States
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26
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Ducret V, Richards AJ, Videlier M, Scalvenzi T, Moore KA, Paszkiewicz K, Bonneaud C, Pollet N, Herrel A. Transcriptomic analysis of the trade-off between endurance and burst-performance in the frog Xenopus allofraseri. BMC Genomics 2021; 22:204. [PMID: 33757428 PMCID: PMC7986297 DOI: 10.1186/s12864-021-07517-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 03/08/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Variation in locomotor capacity among animals often reflects adaptations to different environments. Despite evidence that physical performance is heritable, the molecular basis of locomotor performance and performance trade-offs remains poorly understood. In this study we identify the genes, signaling pathways, and regulatory processes possibly responsible for the trade-off between burst performance and endurance observed in Xenopus allofraseri, using a transcriptomic approach. RESULTS We obtained a total of about 121 million paired-end reads from Illumina RNA sequencing and analyzed 218,541 transcripts obtained from a de novo assembly. We identified 109 transcripts with a significant differential expression between endurant and burst performant individuals (FDR ≤ 0.05 and logFC ≥2), and blast searches resulted in 103 protein-coding genes. We found major differences between endurant and burst-performant individuals in the expression of genes involved in the polymerization and ATPase activity of actin filaments, cellular trafficking, proteoglycans and extracellular proteins secreted, lipid metabolism, mitochondrial activity and regulators of signaling cascades. Remarkably, we revealed transcript isoforms of key genes with functions in metabolism, apoptosis, nuclear export and as a transcriptional corepressor, expressed in either burst-performant or endurant individuals. Lastly, we find two up-regulated transcripts in burst-performant individuals that correspond to the expression of myosin-binding protein C fast-type (mybpc2). This suggests the presence of mybpc2 homoeologs and may have been favored by selection to permit fast and powerful locomotion. CONCLUSION These results suggest that the differential expression of genes belonging to the pathways of calcium signaling, endoplasmic reticulum stress responses and striated muscle contraction, in addition to the use of alternative splicing and effectors of cellular activity underlie locomotor performance trade-offs. Ultimately, our transcriptomic analysis offers new perspectives for future analyses of the role of single nucleotide variants, homoeology and alternative splicing in the evolution of locomotor performance trade-offs.
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Affiliation(s)
- Valérie Ducret
- UMR 7179 MECADEV, C.N.R.S/M.N.H.N., Département Adaptations du Vivant, 55 Rue Buffon, 75005, Paris, France.
| | - Adam J Richards
- Station d'Ecologie Expérimentale du CNRS, USR 2936, 09200, Moulis, France
| | - Mathieu Videlier
- Functional Ecology Lab, Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N 6N5, Canada
| | - Thibault Scalvenzi
- Evolution, Génomes, Comportement & Ecologie, Université Paris-Saclay, CNRS, IRD, 91198, Gif-sur-Yvette, France
| | - Karen A Moore
- Exeter Sequencing Service, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Konrad Paszkiewicz
- Exeter Sequencing Service, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Camille Bonneaud
- Station d'Ecologie Expérimentale du CNRS, USR 2936, 09200, Moulis, France
- Centre for Ecology & Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, UK
| | - Nicolas Pollet
- Evolution, Génomes, Comportement & Ecologie, Université Paris-Saclay, CNRS, IRD, 91198, Gif-sur-Yvette, France
| | - Anthony Herrel
- Station d'Ecologie Expérimentale du CNRS, USR 2936, 09200, Moulis, France
- Evolutionary Morphology of Vertebrates, Ghent University, B-9000, Ghent, Belgium
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Effects of Long-Term DHA Supplementation and Physical Exercise on Non-Alcoholic Fatty Liver Development in Obese Aged Female Mice. Nutrients 2021; 13:nu13020501. [PMID: 33546405 PMCID: PMC7913512 DOI: 10.3390/nu13020501] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/22/2021] [Accepted: 01/26/2021] [Indexed: 02/06/2023] Open
Abstract
Obesity and aging are associated to non-alcoholic fatty liver disease (NAFLD) development. Here, we investigate whether long-term feeding with a docosahexaenoic acid (DHA)-enriched diet and aerobic exercise, alone or in combination, are effective in ameliorating NAFLD in aged obese mice. Two-month-old female C57BL/6J mice received control or high fat diet (HFD) for 4 months. Then, the diet-induced obese (DIO) mice were distributed into four groups: DIO, DIO + DHA (15% dietary lipids replaced by a DHA-rich concentrate), DIO + EX (treadmill running), and DIO + DHA + EX up to 18 months. The DHA-rich diet reduced liver steatosis in DIO mice, decreasing lipogenic genes (Dgat2, Scd1, Srebp1c), and upregulated lipid catabolism genes (Hsl/Acox) expression. A similar pattern was observed in the DIO + EX group. The combination of DHA + exercise potentiated an increase in Cpt1a and Ppara genes, and AMPK activation, key regulators of fatty acid oxidation. Exercise, alone or in combination with DHA, significantly reversed the induction of proinflammatory genes (Mcp1, Il6, Tnfα, Tlr4) in DIO mice. DHA supplementation was effective in preventing the alterations induced by the HFD in endoplasmic reticulum stress-related genes (Ern1/Xbp1) and autophagy markers (LC3II/I ratio, p62, Atg7). In summary, long-term DHA supplementation and/or exercise could be helpful to delay NAFLD progression during aging in obesity.
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Aron-Wisnewsky J, Warmbrunn MV, Nieuwdorp M, Clément K. Metabolism and Metabolic Disorders and the Microbiome: The Intestinal Microbiota Associated With Obesity, Lipid Metabolism, and Metabolic Health-Pathophysiology and Therapeutic Strategies. Gastroenterology 2021; 160:573-599. [PMID: 33253685 DOI: 10.1053/j.gastro.2020.10.057] [Citation(s) in RCA: 161] [Impact Index Per Article: 53.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 10/26/2020] [Accepted: 10/26/2020] [Indexed: 12/12/2022]
Abstract
Changes in the intestinal microbiome have been associated with obesity and type 2 diabetes, in epidemiological studies and studies of the effects of fecal transfer in germ-free mice. We review the mechanisms by which alterations in the intestinal microbiome contribute to development of metabolic diseases, and recent advances, such as the effects of the microbiome on lipid metabolism. Strategies have been developed to modify the intestinal microbiome and reverse metabolic alterations, which might be used as therapies. We discuss approaches that have shown effects in mouse models of obesity and metabolic disorders, and how these might be translated to humans to improve metabolic health.
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Affiliation(s)
- Judith Aron-Wisnewsky
- Nutrition and Obesities: Systemic Approaches Research Unit (Nutriomics), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale, Paris, France; Nutrition Department, Assistante Publique Hôpitaux de Paris, Pitié-Salpêtrière Hospital, Centres de Recherche en Nutrition Humaine Ile de France, Paris, France; Department of Vascular Medicine, Amsterdam Universitair Medische Centra, location Academisch Medisch Centrum, and VUMC, University of Amsterdam, Amsterdam, the Netherlands.
| | - Moritz V Warmbrunn
- Department of Vascular Medicine, Amsterdam Universitair Medische Centra, location Academisch Medisch Centrum, and VUMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Max Nieuwdorp
- Department of Vascular Medicine, Amsterdam Universitair Medische Centra, location Academisch Medisch Centrum, and VUMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Karine Clément
- Nutrition and Obesities: Systemic Approaches Research Unit (Nutriomics), Sorbonne Université, Institut National de la Santé et de la Recherche Médicale, Paris, France; Nutrition Department, Assistante Publique Hôpitaux de Paris, Pitié-Salpêtrière Hospital, Centres de Recherche en Nutrition Humaine Ile de France, Paris, France.
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Hepatic synthesis of triacylglycerols containing medium-chain fatty acids is dominated by diacylglycerol acyltransferase 1 and efficiently inhibited by etomoxir. Mol Metab 2020; 45:101150. [PMID: 33359403 PMCID: PMC7843514 DOI: 10.1016/j.molmet.2020.101150] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 12/07/2020] [Accepted: 12/16/2020] [Indexed: 11/30/2022] Open
Abstract
Objective Medium-chain fatty acids (MCFAs) play an increasing role in human nutrition. In the liver, one fraction is used for synthesis of MCFA-containing triacylglycerol (MCFA-TG), and the rest is used for oxidative energy production or ketogenesis. We investigated which enzymes catalyse the synthesis of MCFA-TG and how inhibition of MCFA-TG synthesis or fatty acid (FA) oxidation influences the metabolic fate of the MCFAs. Methods FA metabolism was followed by time-resolved tracing of alkyne-labelled FAs in freshly isolated mouse hepatocytes. Quantitative data were obtained by mass spectrometry of several hundred labelled lipid species. Wild-type hepatocytes and cells from diacylglycerol acyltransferase (DGAT)1−/− mice were treated with inhibitors against DGAT1, DGAT2, or FA β-oxidation. Results Inhibition or deletion of DGAT1 resulted in a reduction of MCFA-TG synthesis by 70%, while long-chain (LC)FA-TG synthesis was reduced by 20%. In contrast, DGAT2 inhibition increased MCFA-TG formation by 50%, while LCFA-TG synthesis was reduced by 5–25%. Inhibition of β-oxidation by the specific inhibitor teglicar strongly increased MCFA-TG synthesis. In contrast, the widely used β-oxidation inhibitor etomoxir blocked MCFA-TG synthesis, phenocopying DGAT1 inhibition. Conclusions DGAT1 is the major enzyme for hepatic MCFA-TG synthesis. Its loss can only partially be compensated by DGAT2. Specific inhibition of β-oxidation leads to a compensatory increase in MCFA-TG synthesis, whereas etomoxir blocks both β-oxidation and MCFA-TG synthesis, indicating a strong off-target effect on DGAT1.
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30
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Mashek DG. Hepatic lipid droplets: A balancing act between energy storage and metabolic dysfunction in NAFLD. Mol Metab 2020; 50:101115. [PMID: 33186758 PMCID: PMC8324678 DOI: 10.1016/j.molmet.2020.101115] [Citation(s) in RCA: 104] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/21/2020] [Accepted: 11/06/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Non-alcoholic fatty liver disease (NAFLD) is defined by the abundance of lipid droplets (LDs) in hepatocytes. While historically considered simply depots for energy storage, LDs are increasingly recognized to impact a wide range of biological processes that influence cellular metabolism, signaling, and function. While progress has been made toward understanding the factors leading to LD accumulation (i.e. steatosis) and its progression to advanced stages of NAFLD and/or systemic metabolic dysfunction, much remains to be resolved. SCOPE OF REVIEW This review covers many facets of LD biology. We provide a brief overview of the major pathways of lipid accretion and degradation that contribute to steatosis and how they are altered in NAFLD. The major focus is on the relationship between LDs and cell function and the detailed mechanisms that couple or uncouple steatosis from the severity and progression of NAFLD and systemic comorbidities. The importance of specific lipids and proteins within or on LDs as key components that determine whether LD accumulation is linked to cellular and metabolic dysfunction is presented. We discuss emerging areas of LD biology and future research directions that are needed to advance our understanding of the role of LDs in NAFLD etiology. MAJOR CONCLUSIONS Impairments in LD breakdown appear to contribute to disease progression, but inefficient incorporation of fatty acids (FAs) into LD-containing triacylglycerol (TAG) and the consequential changes in FA partitioning also affect NAFLD etiology. Increased LD abundance in hepatocytes does not necessarily equate to cellular dysfunction. While LD accumulation is the prerequisite step for most NAFLD cases, the protein and lipid composition of LDs are critical factors in determining the progression from simple steatosis. Further defining the detailed molecular mechanisms linking LDs to metabolic dysfunction is important for designing effective therapeutic approaches targeting NAFLD and its comorbidities.
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Affiliation(s)
- Douglas G Mashek
- Department of Biochemistry, Molecular Biology, and Biophysics, Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, University of Minnesota, Suite 6-155, 321 Church St. SE, Minneapolis, MN, 55455, USA.
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31
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Playing Jekyll and Hyde-The Dual Role of Lipids in Fatty Liver Disease. Cells 2020; 9:cells9102244. [PMID: 33036257 PMCID: PMC7601321 DOI: 10.3390/cells9102244] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 09/27/2020] [Accepted: 10/01/2020] [Indexed: 12/12/2022] Open
Abstract
Lipids play Jekyll and Hyde in the liver. On the one hand, the lipid-laden status of hepatic stellate cells is a hallmark of healthy liver. On the other hand, the opposite is true for lipid-laden hepatocytes—they obstruct liver function. Neglected lipid accumulation in hepatocytes can progress into hepatic fibrosis, a condition induced by the activation of stellate cells. In their resting state, these cells store substantial quantities of fat-soluble vitamin A (retinyl esters) in large lipid droplets. During activation, these lipid organelles are gradually degraded. Hence, treatment of fatty liver disease is treading a tightrope—unsophisticated targeting of hepatic lipid accumulation might trigger problematic side effects on stellate cells. Therefore, it is of great importance to gain more insight into the highly dynamic lipid metabolism of hepatocytes and stellate cells in both quiescent and activated states. In this review, part of the special issue entitled “Cellular and Molecular Mechanisms underlying the Pathogenesis of Hepatic Fibrosis 2020”, we discuss current and highly versatile aspects of neutral lipid metabolism in the pathogenesis of non-alcoholic fatty liver disease (NAFLD).
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32
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Amin NB, Carvajal-Gonzalez S, Purkal J, Zhu T, Crowley C, Perez S, Chidsey K, Kim AM, Goodwin B. Targeting diacylglycerol acyltransferase 2 for the treatment of nonalcoholic steatohepatitis. Sci Transl Med 2020; 11:11/520/eaav9701. [PMID: 31776293 DOI: 10.1126/scitranslmed.aav9701] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 02/25/2019] [Accepted: 11/08/2019] [Indexed: 12/14/2022]
Abstract
Nonalcoholic steatohepatitis (NASH) is characterized by the accumulation of hepatocyte triglycerides, the synthesis of which is catalyzed by diacylglycerol acyltransferases (DGATs). Here, we investigate DGAT2 as a potential therapeutic target using an orally administered, selective DGAT2 inhibitor, PF-06427878. Treatment with PF-06427878 resulted in the reduction of hepatic and circulating plasma triglyceride concentrations and decreased lipogenic gene expression in rats maintained on a Western-type diet. In a mouse model of NASH, histological improvements in steatosis, ballooning, and fibrosis were evident in the livers of animals receiving PF-06427878 compared with mice treated with vehicle alone. We extended these nonclinical studies to two phase 1 studies in humans [NCT02855177 (n = 24) and NCT02391623 (n = 39; n = 38 completed)] and observed that PF-06427878 was well tolerated and influenced markers of liver function (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and total bilirubin) in healthy adults, with statistically significant reductions from baseline at day 14 in participants treated with PF-06427878 1500 milligrams per day (P < 0.05). Moreover, magnetic resonance imaging using proton density fat fraction showed that PF-06427878 1500 milligrams per day reduced hepatic steatosis in healthy adult participants. Our findings highlight DGAT2 inhibition by a small, potent, selective compound as a potential therapeutic approach for the treatment of NASH.
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Affiliation(s)
- Neeta B Amin
- Internal Medicine Research Unit, Pfizer Worldwide Research and Development, Cambridge, MA 02139, USA.
| | | | - Julie Purkal
- Internal Medicine Research Unit, Pfizer Worldwide Research and Development, Cambridge, MA 02139, USA
| | - Tong Zhu
- Early Clinical Development, Pfizer Worldwide Research and Development, Cambridge, MA 02139, USA
| | - Collin Crowley
- Internal Medicine Research Unit, Pfizer Worldwide Research and Development, Cambridge, MA 02139, USA
| | - Sylvie Perez
- Internal Medicine Research Unit, Pfizer Worldwide Research and Development, Cambridge, MA 02139, USA
| | - Kristin Chidsey
- Early Clinical Development, Pfizer Worldwide Research and Development, Cambridge, MA 02139, USA
| | - Albert M Kim
- Internal Medicine Research Unit, Pfizer Worldwide Research and Development, Cambridge, MA 02139, USA
| | - Bryan Goodwin
- Internal Medicine Research Unit, Pfizer Worldwide Research and Development, Cambridge, MA 02139, USA
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Guarino M, Kumar P, Felser A, Terracciano LM, Guixé-Muntet S, Humar B, Foti M, Nuoffer JM, St-Pierre MV, Dufour JF. Exercise Attenuates the Transition from Fatty Liver to Steatohepatitis and Reduces Tumor Formation in Mice. Cancers (Basel) 2020; 12:E1407. [PMID: 32486073 PMCID: PMC7352494 DOI: 10.3390/cancers12061407] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/18/2020] [Accepted: 05/26/2020] [Indexed: 02/06/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) leads to steatohepatitis (NASH), fibrosis, and hepatocellular carcinoma. For sedentary patients, lifestyle interventions combining exercise and dietary changes are a cornerstone of treatment. However, the benefit of exercise alone when dietary changes have failed is uncertain. We query whether exercise alone arrests the progression of NASH and tumorigenesis in a choline-deficient, high-fat diet (CD-HFD) murine model. Male C57Bl/6N mice received a control diet or CD-HFD for 12 weeks. CD-HFD mice were randomized further for 8 weeks of sedentariness (SED) or treadmill exercise (EXE). CD-HFD for 12 weeks produced NAFL. After 20 weeks, SED mice developed NASH and hepatic adenomas. Exercise attenuated the progression to NASH. EXE livers showed lower triglycerides and tumor necrosis factor-α expression, less fibrosis, less ballooning, and a lower NAFLD activity score than did SED livers. Plasma transaminases and triglycerides were lower. Exercise activated AMP-activated protein kinase (AMPK) with inhibition of mTORC1 and decreased S6 phosphorylation, reducing hepatocellular adenoma. Exercise activated autophagy with increased LC3-II/LC3-I and mitochondrial recruitment of phosphorylated PTEN-induced kinase. Therefore, exercise attenuates the transition from NAFL to NASH, improves biochemical and histological parameters of NAFLD, and impedes the progression of fibrosis and tumorigenesis associated with enhanced activation of AMPK signaling and favors liver autophagy. Our work supports the benefits of exercise independently of dietary changes.
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Affiliation(s)
- Maria Guarino
- Hepatology, Department for BioMedical Research, University of Bern, 3008 Bern, Switzerland; (M.G.); (P.K.); (S.G.-M.); (M.V.S.-P.)
- Gastroenterology, Department of Clinical Medicine and Surgery, University of Naples “Federico II”, 80131 Naples, Italy
| | - Pavitra Kumar
- Hepatology, Department for BioMedical Research, University of Bern, 3008 Bern, Switzerland; (M.G.); (P.K.); (S.G.-M.); (M.V.S.-P.)
| | - Andrea Felser
- University Institute of Clinical Chemistry, Bern University Hospital, 3010 Bern, Switzerland; (A.F.); (J.-M.N.)
| | | | - Sergi Guixé-Muntet
- Hepatology, Department for BioMedical Research, University of Bern, 3008 Bern, Switzerland; (M.G.); (P.K.); (S.G.-M.); (M.V.S.-P.)
| | - Bostjan Humar
- Laboratory of the Swiss Hepato-Pancreato-Biliary (HPB) and Transplantation Center, Department of Surgery, University Hospital Zürich, 8091 Zürich, Switzerland;
| | - Michelangelo Foti
- Department of Cell Physiology and Metabolism, University of Geneva, 1206 Geneva, Switzerland;
| | - Jean-Marc Nuoffer
- University Institute of Clinical Chemistry, Bern University Hospital, 3010 Bern, Switzerland; (A.F.); (J.-M.N.)
| | - Marie V. St-Pierre
- Hepatology, Department for BioMedical Research, University of Bern, 3008 Bern, Switzerland; (M.G.); (P.K.); (S.G.-M.); (M.V.S.-P.)
| | - Jean-François Dufour
- Hepatology, Department for BioMedical Research, University of Bern, 3008 Bern, Switzerland; (M.G.); (P.K.); (S.G.-M.); (M.V.S.-P.)
- University Clinic of Visceral Surgery and Medicine, Inselspital Bern, 3010 Bern, Switzerland
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Stephan M, Volkmann P, Rossner MJ. Assessing behavior and cognition in rodents, nonhuman primates, and humans: where are the limits of translation?
. DIALOGUES IN CLINICAL NEUROSCIENCE 2020; 21:249-259. [PMID: 31749649 PMCID: PMC6829167 DOI: 10.31887/dcns.2019.21.3/mrossner] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
New psychopharmacological treatments are needed for affective and nonaffective
psychoses, especially for the associated negative and cognitive symptoms. Earlier
developments mostly failed, probably partly because of limitations in behavioral models
used for validation. Now, deeper understanding of the genetics underlying disease
pathogenesis and progress in genetic engineering will generate many rodent models with
increased construct validity. To improve these models’ translational value, we need
complementary data from nonhuman primates. We also have to improve and streamline
behavioral test systems to cope with increased demand. Here, we propose a comprehensive
neurocognitive test battery that should overcome the disadvantages of single tests and
yield cognitive/behavioral profiles for modeling subsets of patient symptoms. Further,
we delineate a concept for classifying disease-relevant cognitive endophenotypes to
balance between face and construct validity and clinical diagnostics. In summary, this
review discusses new concepts and the limitations and future potential of translational
research on cognition in psychiatry.
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Affiliation(s)
- Marius Stephan
- Molecular and Behavioural Neurobiology, Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Germany; International Max Planck Research School for Translational Psychiatry (IMPRS-TP), Munich, Germany
| | - Paul Volkmann
- Molecular and Behavioural Neurobiology, Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Germany
| | - Moritz J Rossner
- Molecular and Behavioural Neurobiology, Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Germany
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Oishi K, Miyazaki M, Takase R, Chigwechokha PK, Komatsu M, Shiozaki K. Regulation of triglyceride metabolism in medaka (Oryzias latipes) hepatocytes by Neu3a sialidase. FISH PHYSIOLOGY AND BIOCHEMISTRY 2020; 46:563-574. [PMID: 31792756 DOI: 10.1007/s10695-019-00730-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 11/01/2019] [Indexed: 06/10/2023]
Abstract
Fish store triglycerides (TGs) in the liver, muscle, and adipose tissue and TGs constitute an energy source upon metabolic demand. The liver generally plays important roles in lipid metabolism. Recent studies have suggested the possibility of hepatic lipid metabolic regulation by ganglioside in mammals; however, ganglioside-mediated regulation of lipid metabolism is unclear in fish. This study aimed to clarify the role of ganglioside in fish TG metabolism, with particular reference to Neu3a, a ganglioside-specific sialidase expressed in the fish liver. Under fasting conditions, there was a decrease in hepatic TG contents, and neu3a mRNA level was significantly up-regulated in the medaka liver. To determine the role of Neu3a in hepatic lipid metabolism, Neu3a stable transfectants were generated using fish liver Hepa-T1 cells. After treating Neu3a cells with oleic acid, reduction of TG was detected in comparison with the mock cells. Furthermore, lipase activity was greater in Neu3a cells than in mock cells. To examine which ganglioside regulates these events, alterations of ganglioside composition in Neu3a cells were analyzed. Neu3a cells exhibited increased level of lactosylceramide (LacCer), a Neu3 enzymatic product originating from GM3. In addition, exposure of LacCer toward Hepa-T1 cells resulted in an increase of neutral lipase activity. The present results suggest that Neu3a up-regulation in medaka under fasting condition accelerates hepatic TG degradation for energy production via GM3 desialylation.
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Affiliation(s)
- Kazuki Oishi
- Faculty of Fisheries, Kagoshima University, Kagoshima, 890-0056, Japan
- The United Graduate School of Agricultural Sciences, Kagoshima University, 4-50-20 Shimoarata, Kagoshima, 890-0056, Japan
| | - Mina Miyazaki
- Faculty of Fisheries, Kagoshima University, Kagoshima, 890-0056, Japan
| | - Ryo Takase
- Faculty of Fisheries, Kagoshima University, Kagoshima, 890-0056, Japan
| | | | - Masaharu Komatsu
- Faculty of Fisheries, Kagoshima University, Kagoshima, 890-0056, Japan
- The United Graduate School of Agricultural Sciences, Kagoshima University, 4-50-20 Shimoarata, Kagoshima, 890-0056, Japan
| | - Kazuhiro Shiozaki
- Faculty of Fisheries, Kagoshima University, Kagoshima, 890-0056, Japan.
- The United Graduate School of Agricultural Sciences, Kagoshima University, 4-50-20 Shimoarata, Kagoshima, 890-0056, Japan.
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Ma N, Ma R, Tang K, Li X, He B. Roux-en-Y Gastric Bypass in Obese Diabetic Rats Promotes Autophagy to Improve Lipid Metabolism through mTOR/p70S6K Signaling Pathway. J Diabetes Res 2020; 2020:4326549. [PMID: 32309446 PMCID: PMC7136782 DOI: 10.1155/2020/4326549] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 01/28/2020] [Accepted: 02/12/2020] [Indexed: 12/14/2022] Open
Abstract
PURPOSE To investigate the effects of Roux-en-Y gastric bypass (RYGB) surgery on markers of liver mitochondrial dynamics and find new therapeutic basis on obese type 2 diabetes mellitus (T2DM) patients. Materials and Methods. Thirty-two rats were divided into nondiabetic group, diabetic group, sham group, and RYGB group. The Dual-energy X-ray absorptiometry (DEXA) was used to detect short-term curriculum vitae for rat body component and fat and lean mass. Hepatic lipid content and triglyceride levels were detected by Oil Red O staining. Western blotting was used to examine autophagy and mammalian target of rapamycin/P70S6 kinase (mTOR/p70S6K) pathway-related proteins. The carbon dioxide production from the oxidation of [14C] oleate was measured. Plasma glucose was measured by glucose oxidase assay. The insulin and C-peptide were detected. Triacylglyceride (TG) and free fat acid (FFA) in plasma were determined by enzymatic colorimetric assays. RESULTS RYGB improved metabolic parameters and enhanced plasma GLP-1 level, ameliorated the lipopexia, and increased insulin sensitivity in the liver; RYGB promoted the hepatic autophagy and inhibited the mTOR/p70S6K signaling pathway. GLP-1 reduced fat load and increased fatty acid β-oxidation by activated autophagy to regulate the hepatic lipid pathway through mTOR/p70S6K signaling pathway. CONCLUSIONS RYGB may reduce liver lipid toxicity and improve insulin sensitivity through activating the hepatic fat hydrolysis pathway and inhibiting the liver fat synthesis pathway. However, the transport pathway of liver fat does not play a key role.
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Affiliation(s)
- Nanxi Ma
- Department of Endocrinology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, China
| | - Rui Ma
- Department of Endocrinology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, China
| | - Kaixin Tang
- Department of Endocrinology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, China
| | - Xuesong Li
- Department of Endocrinology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, China
| | - Bing He
- Department of Endocrinology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, China
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Gluchowski NL, Gabriel KR, Chitraju C, Bronson RT, Mejhert N, Boland S, Wang K, Lai ZW, Farese RV, Walther TC. Hepatocyte Deletion of Triglyceride-Synthesis Enzyme Acyl CoA: Diacylglycerol Acyltransferase 2 Reduces Steatosis Without Increasing Inflammation or Fibrosis in Mice. Hepatology 2019; 70:1972-1985. [PMID: 31081165 PMCID: PMC6893913 DOI: 10.1002/hep.30765] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 05/05/2019] [Indexed: 12/31/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is characterized by excess lipid accumulation in hepatocytes and represents a huge public health problem owing to its propensity to progress to nonalcoholic steatohepatitis, fibrosis, and liver failure. The lipids stored in hepatic steatosis (HS) are primarily triglycerides (TGs) synthesized by two acyl-CoA:diacylglycerol acyltransferase (DGAT) enzymes. Either DGAT1 or DGAT2 catalyzes this reaction, and these enzymes have been suggested to differentially utilize exogenous or endogenously synthesized fatty acids, respectively. DGAT2 has been linked to storage of fatty acids from de novo lipogenesis, a process increased in NAFLD. However, whether DGAT2 is more responsible for lipid accumulation in NAFLD and progression to fibrosis is currently unknown. Also, it is unresolved whether DGAT2 can be safely inhibited as a therapy for NAFLD. Here, we induced NAFLD-like disease in mice by feeding a diet rich in fructose, saturated fat, and cholesterol and found that hepatocyte-specific Dgat2 deficiency reduced expression of de novo lipogenesis genes and lowered liver TGs by ~70%. Importantly, the reduction in steatosis was not accompanied by increased inflammation or fibrosis, and insulin and glucose metabolism were unchanged. Conclusion: This study suggests that hepatic DGAT2 deficiency successfully reduces diet-induced HS and supports development of DGAT2 inhibitors as a therapeutic strategy for treating NAFLD and preventing downstream consequences.
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Affiliation(s)
- Nina L. Gluchowski
- Division of Gastroenterology and Nutrition, Boston Children’s Hospital, Boston, MA
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA
- Department of Cell Biology, Harvard Medical School, Boston, MA
| | - Katlyn R. Gabriel
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA
- Department of Cell Biology, Harvard Medical School, Boston, MA
- Howard Hughes Medical Institute, Boston, MA
| | - Chandramohan Chitraju
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA
- Department of Cell Biology, Harvard Medical School, Boston, MA
| | | | - Niklas Mejhert
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA
- Department of Cell Biology, Harvard Medical School, Boston, MA
| | - Sebastian Boland
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA
- Department of Cell Biology, Harvard Medical School, Boston, MA
| | - Kun Wang
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA
- Department of Cell Biology, Harvard Medical School, Boston, MA
| | - Zon Weng Lai
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA
- Department of Cell Biology, Harvard Medical School, Boston, MA
| | - Robert V. Farese
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA
- Department of Cell Biology, Harvard Medical School, Boston, MA
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, MA
| | - Tobias C. Walther
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA
- Department of Cell Biology, Harvard Medical School, Boston, MA
- Howard Hughes Medical Institute, Boston, MA
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, MA
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38
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Hodson L, Gunn PJ. The regulation of hepatic fatty acid synthesis and partitioning: the effect of nutritional state. Nat Rev Endocrinol 2019; 15:689-700. [PMID: 31554932 DOI: 10.1038/s41574-019-0256-9] [Citation(s) in RCA: 133] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is an increasing global public health burden. NAFLD is strongly associated with type 2 diabetes mellitus, obesity and cardiovascular disease and begins with intrahepatic triacylglycerol accumulation. Under healthy conditions, the liver regulates lipid metabolism to meet systemic energy needs in the fed and fasted states. The processes of fatty acid uptake, fatty acid synthesis and the intracellular partitioning of fatty acids into storage, oxidation and secretion pathways are tightly regulated. When one or more of these processes becomes dysregulated, excess lipid accumulation can occur. Although genetic and environmental factors have been implicated in the development of NAFLD, it remains unclear why an imbalance in these pathways begins. The regulation of fatty acid partitioning occurs at several points, including during triacylglycerol synthesis, lipid droplet formation and lipolysis. These processes are influenced by enzyme function, intake of dietary fats and sugars and whole-body metabolism, and are further affected by the presence of obesity or insulin resistance. Insight into how the liver controls fatty acid metabolism in health and how these processes might be affected in disease would offer the potential for new therapeutic treatments for NAFLD to be developed.
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Affiliation(s)
- Leanne Hodson
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Headington, Oxford, UK.
- Oxford NIHR Biomedical Research Centre, Churchill Hospital, Headington, Oxford, UK.
| | - Pippa J Gunn
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Headington, Oxford, UK
- Oxford NIHR Biomedical Research Centre, Churchill Hospital, Headington, Oxford, UK
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39
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Lawrence MC, Darden CM, Vasu S, Kumano K, Gu J, Wang X, Chan J, Xu Z, Lemoine BF, Nguyen P, Smitherman C, Naziruddin B, Testa G. Profiling Gene Programs in the Blood During Liver Regeneration in Living Liver Donors. Liver Transpl 2019; 25:1541-1560. [PMID: 31340088 DOI: 10.1002/lt.25608] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 07/17/2019] [Indexed: 02/07/2023]
Abstract
The human liver's capacity to rapidly regenerate to a full-sized functional organ after resection has allowed successful outcomes for living donor liver transplantation (LDLT) procedures. However, the ability to detect and track physiological changes occurring during liver regeneration after resection and throughout the restoration process is still lacking. We performed a comprehensive whole-transcriptome RNA sequencing analysis of liver and circulating blood tissue from 12 healthy LDLT donors to define biomarker signatures for monitoring physiological activities during liver regeneration at 14 time points for up to a 1-year procedural follow-up. LDLT donor liver tissue differentially expressed 1238 coding and noncoding genes after resection, and an additional 1260 genes were selectively regulated after LDLT. A total of 15,011 RNA transcript species were identified in the blood in response to liver resection. The transcripts most highly regulated were sequentially expressed within 3 distinct peaks that correlated with sets of functional genes involved in the induction of liver resection-specific innate immune response (peak 1), activation of the complement system (peak 2), and platelet activation and erythropoiesis (peak 3). Each peak corresponded with progressive phases of extracellular matrix degradation, remodeling, and organization during liver restoration. These processes could be tracked by distinct molecular signatures of up-regulated and down-regulated gene profiles in the blood during phases of liver repair and regeneration. In conclusion, the results establish temporal and dynamic transcriptional patterns of gene expression following surgical liver resection that can be detected in the blood and potentially used as biomarker signatures for monitoring phases of liver regeneration.
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Affiliation(s)
| | - Carly M Darden
- Institute of Biomedical Studies, Baylor University, Waco, TX
| | | | | | - Jinghua Gu
- Baylor Scott & White Research Institute, Dallas, TX
| | - Xuan Wang
- Baylor Scott & White Research Institute, Dallas, TX
| | - Jinyan Chan
- Baylor Scott & White Research Institute, Dallas, TX
| | - Zhaohui Xu
- Baylor Scott & White Research Institute, Dallas, TX
| | | | | | | | - Bashoo Naziruddin
- Annette C. and Harold C. Simmons Transplant Institute, Baylor University Medical Center, Dallas, TX
| | - Giuliano Testa
- Annette C. and Harold C. Simmons Transplant Institute, Baylor University Medical Center, Dallas, TX
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40
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Faught E, Vijayan MM. Postnatal triglyceride accumulation is regulated by mineralocorticoid receptor activation under basal and stress conditions. J Physiol 2019; 597:4927-4941. [DOI: 10.1113/jp278088] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 06/26/2019] [Indexed: 12/17/2022] Open
Affiliation(s)
- Erin Faught
- Department of Biological SciencesUniversity of Calgary Calgary Alberta Canada
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41
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Romani M, Hofer DC, Katsyuba E, Auwerx J. Niacin: an old lipid drug in a new NAD + dress. J Lipid Res 2019; 60:741-746. [PMID: 30782960 PMCID: PMC6446705 DOI: 10.1194/jlr.s092007] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Indexed: 12/29/2022] Open
Abstract
Niacin, the first antidyslipidemic drug, has been at the center stage of lipid research for many decades before the discovery of statins. However, to date, despite its remarkable effects on lipid profiles, the clinical outcomes of niacin treatment on cardiac events is still debated. In addition to its historically well-defined interactions with central players of lipid metabolism, niacin can be processed by eukaryotic cells to synthesize a crucial cofactor, NAD+ NAD+ acts as a cofactor in key cellular processes, including oxidative phosphorylation, glycolysis, and DNA repair. More recently, evidence has emerged that NAD+ also is an essential cosubstrate for the sirtuin family of protein deacylases and thereby has an impact on a wide range of cellular processes, most notably mitochondrial homeostasis, energy homeostasis, and lipid metabolism. NAD+ achieves these remarkable effects through sirtuin-mediated deacetylation of key transcriptional regulators, such as peroxisome proliferator-activated receptor gamma coactivator 1-α, LXR, and SREBPs, that control these cellular processes. Here, we present an alternative point of view to explain niacin's mechanism of action, with a strong focus on the importance of how this old drug acts as a control switch of NAD+/sirtuin-mediated control of metabolism.
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Affiliation(s)
- Mario Romani
- Laboratory of Integrative Systems Physiology, Interfaculty Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Dina Carina Hofer
- Laboratory of Integrative Systems Physiology, Interfaculty Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Elena Katsyuba
- Laboratory of Integrative Systems Physiology, Interfaculty Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Johan Auwerx
- Laboratory of Integrative Systems Physiology, Interfaculty Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
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42
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Chitraju C, Walther TC, Farese RV. The triglyceride synthesis enzymes DGAT1 and DGAT2 have distinct and overlapping functions in adipocytes. J Lipid Res 2019; 60:1112-1120. [PMID: 30936184 PMCID: PMC6547635 DOI: 10.1194/jlr.m093112] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 03/28/2019] [Indexed: 12/22/2022] Open
Abstract
Mammals store metabolic energy as triacylglycerols (TGs) in adipose tissue. TG synthesis is catalyzed by the evolutionarily unrelated acyl-CoA:diacylglycerol acyltransferase (DGAT) enzymes DGAT1 and DGAT2, which catalyze the same reaction and account for nearly all TG synthesis. The reasons for their convergent evolution to synthesize TGs remain unclear. Mice lacking DGAT1 are viable with reduced fat stores of TGs, whereas DGAT2 KO mice die postnatally just after birth with >90% reduction of TGs, suggesting that DGAT2 is the predominant enzyme for TG storage. To better understand the functional differences between the DGATs, we studied mice fed chow or high-fat diets lacking either enzyme in adipose tissue. Unexpectedly, mice lacking DGAT2 in adipocytes have normal TG storage and glucose metabolism on regular or high-fat diets, indicating DGAT2 is not essential for fat storage. In contrast, mice lacking DGAT1 in adipocytes have normal TG storage on a chow diet but moderately decreased body fat accompanied by glucose intolerance when challenged with a high-fat diet. The latter changes were associated with the activation of ER stress pathways. We conclude that DGAT1 and DGAT2 can largely compensate for each other for TG storage but that DGAT1 uniquely has an important role in protecting the ER from the lipotoxic effects of high-fat diets.
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Affiliation(s)
- Chandramohan Chitraju
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115.,Department of Cell Biology, Harvard Medical School, Boston, MA 02115
| | - Tobias C Walther
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115 .,Department of Cell Biology, Harvard Medical School, Boston, MA 02115.,Broad Institute of MIT and Harvard, Cambridge, MA 02142.,Howard Hughes Medical Institute, Boston, MA 02115
| | - Robert V Farese
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115 .,Department of Cell Biology, Harvard Medical School, Boston, MA 02115.,Broad Institute of MIT and Harvard, Cambridge, MA 02142
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43
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Irshad Z, Chmel N, Adya R, Zammit VA. Hepatic VLDL secretion: DGAT1 determines particle size but not particle number, which can be supported entirely by DGAT2. J Lipid Res 2019; 60:111-120. [PMID: 30397187 PMCID: PMC6314258 DOI: 10.1194/jlr.m089300] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 10/08/2018] [Indexed: 12/25/2022] Open
Abstract
We investigated whether, in view of its activity being expressed on both aspects of the endoplasmic reticulum (ER; dual membrane topology), diacylglycerol acyltransferase 1 (DGAT1) plays a distinctive role in determining the triglyceride (TAG) content of VLDL particles secreted by the liver. Mice in which the DGAT1 gene was specifically ablated in hepatocytes (DGAT1-LKO mice) had the same number of VLDL particles (apoB concentration) in the plasma 1 h after Triton 1339 treatment, but these particles were approximately half the size of VLDL particles secreted by control mice and had a proportionately decreased content of TAG, with normal cholesterol and cholesteryl ester contents. Analyses of purified microsomal fractions prepared from 16 h fasted control and DAGT1-LKO mice showed that the TAG/protein ratio in the ER was significantly lower in the latter. Electron micrographs of these livers showed that those from DGAT1-LKO mice did not show the increased lipid content of the smooth ER shown by control livers. The effects of DGAT1- and DGAT2-specific inhibitors on apoB secretion by HepG2 cells showed that DGAT1 is not indispensable for apoB secretion and demonstrated redundancy in the ability of the two enzymes to support apoB secretion. Therefore, our findings show that DGAT1 is essential for the complete lipidation and maturation of VLDL particles within the lumen of the ER, consistent with its dual topology within the ER membrane. In the mouse, DGAT2 can support apoB secretion (particle number) even when TAG availability for full VLDL lipidation is restricted in the absence of DGAT1.
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Affiliation(s)
- Zehra Irshad
- Translational and Experimental Medicine, Warwick Medical School, Coventry CV4 7AL, United Kingdom
| | - Nikola Chmel
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Raghu Adya
- Translational and Experimental Medicine, Warwick Medical School, Coventry CV4 7AL, United Kingdom
| | - Victor A Zammit
- Translational and Experimental Medicine, Warwick Medical School, Coventry CV4 7AL, United Kingdom
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44
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Pabst B, Futatsugi K, Li Q, Ahn K. Mechanistic Characterization of Long Residence Time Inhibitors of Diacylglycerol Acyltransferase 2 (DGAT2). Biochemistry 2018; 57:6997-7010. [DOI: 10.1021/acs.biochem.8b01096] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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45
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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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46
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Devasthale P, Cheng D. Monoacylglycerol Acyltransferase 2 (MGAT2) Inhibitors for the Treatment of Metabolic Diseases and Nonalcoholic Steatohepatitis (NASH). J Med Chem 2018; 61:9879-9888. [PMID: 29986142 DOI: 10.1021/acs.jmedchem.8b00864] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Monoacylglycerol transferase 2 (MGAT2) is a pivotal enzyme in the monoacylglycerol pathway for triacylglycerol synthesis. The pathway for triacylglycerol synthesis has provided several attractive targets for drug discovery in the treatment of metabolic diseases. Marketed drugs that inhibit enzymes in this pathway include orlistat (pancreatic lipase inhibitor), lomitapide (mitochondrial transfer protein inhibitor), and mipomersen (apolipoprotein B synthesis inhibitor), but poor gastrointestinal (GI) tolerability or safety considerations have limited their use and indications. In addition, several inhibitors of diacylglycerol transferase 1 (DGAT1) have advanced to the clinic but were withdrawn due to poor GI tolerability. This report first discusses the biological rationale in support of inhibition of MGAT2 as a therapeutic approach that may offer a distinct and superior efficacy versus GI tolerability profile and then reviews advances in the discovery of small molecule MGAT2 inhibitors for the treatment of metabolic diseases and nonalcoholic steatohepatitis (NASH).
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