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Hughey CC, Puchalska P, Crawford PA. Integrating the contributions of mitochondrial oxidative metabolism to lipotoxicity and inflammation in NAFLD pathogenesis. Biochim Biophys Acta Mol Cell Biol Lipids 2022; 1867:159209. [DOI: 10.1016/j.bbalip.2022.159209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 06/25/2022] [Accepted: 07/27/2022] [Indexed: 11/28/2022]
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Role of Uncoupling Protein 2 Gene Polymorphisms on the Risk of Ischemic Stroke in a Sardinian Population. Life (Basel) 2022; 12:life12050721. [PMID: 35629388 PMCID: PMC9147365 DOI: 10.3390/life12050721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 05/02/2022] [Accepted: 05/09/2022] [Indexed: 12/05/2022] Open
Abstract
The mitochondrial uncoupling protein 2 (UCP2) acts as an anion transporter and as an antioxidant factor able to reduce the reactive oxygen species level. Based on its effects, UCP2 prevents the membrane lipids, proteins, and DNA damage while preserving normal cellular functions. Many variants have been identified within the human UCP2. Some of them were associated with a higher risk of obesity, diabetes and cardiovascular diseases in different populations. UCP2 appears a suitable candidate also for the risk of ischemic stroke. In the current study, we investigated the possible association between few variants of UCP2 (rs659366, rs660339, rs1554995310) and the risk of ischemic stroke in a genetically homogenous cohort of cases and controls selected in Sardinia Island. This population has been previously analysed for other candidate genes. A total of 250 cases of ischemic stroke and 241 controls were enrolled in the study. The allelic/genotypic distribution of the 3 UCP2 variants was characterized and compared among cases and controls. The results of our study confirmed known risk factors for ischemic stroke: age, history of smoking, hypertension, hypercholesterolemia, and atrial fibrillation. No association was found between the 3 UCP2 variants and the risk of ischemic stroke in our Sardinian cohort.
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Abstract
Non-alcoholic fatty liver disease (NAFLD) is a challenging disease caused by multiple factors, which may partly explain why it still remains an orphan of adequate therapies. This review highlights the interaction between oxidative stress (OS) and disturbed lipid metabolism. Several reactive oxygen species generators, including those produced in the gastrointestinal tract, contribute to the lipotoxic hepatic (and extrahepatic) damage by fatty acids and a great variety of their biologically active metabolites in a “multiple parallel-hit model”. This leads to inflammation and fibrogenesis and contributes to NAFLD progression. The alterations of the oxidant/antioxidant balance affect also metabolism-related organelles, leading to lipid peroxidation, mitochondrial dysfunction, and endoplasmic reticulum stress. This OS-induced damage is at least partially counteracted by the physiological antioxidant response. Therefore, modulation of this defense system emerges as an interesting target to prevent NAFLD development and progression. For instance, probiotics, prebiotics, diet, and fecal microbiota transplantation represent new therapeutic approaches targeting the gut microbiota dysbiosis. The OS and its counter-regulation are under the influence of individual genetic and epigenetic factors as well. In the near future, precision medicine taking into consideration genetic or environmental epigenetic risk factors, coupled with new OS biomarkers, will likely assist in noninvasive diagnosis and monitoring of NAFLD progression and in further personalizing treatments.
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Zhu X, Xia M, Gao X. Update on genetics and epigenetics in metabolic associated fatty liver disease. Ther Adv Endocrinol Metab 2022; 13:20420188221132138. [PMID: 36325500 PMCID: PMC9619279 DOI: 10.1177/20420188221132138] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 09/25/2022] [Indexed: 11/06/2022] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is becoming the most frequent chronic liver disease worldwide. Metabolic (dysfunction) associated fatty liver disease (MAFLD) is suggested to replace the nomenclature of NAFLD. For individuals with metabolic dysfunction, multiple NAFLD-related factors also contribute to the development and progression of MAFLD including genetics and epigenetics. The application of genome-wide association study (GWAS) and exome-wide association study (EWAS) uncovers single-nucleotide polymorphisms (SNPs) in MAFLD. In addition to the classic SNPs in PNPLA3, TM6SF2, and GCKR, some new SNPs have been found recently to contribute to the pathogenesis of liver steatosis. Epigenetic factors involving DNA methylation, histone modifications, non-coding RNAs regulations, and RNA methylation also play a critical role in MAFLD. DNA methylation is the most reported epigenetic modification. Developing a non-invasion biomarker to distinguish metabolic steatohepatitis (MASH) or liver fibrosis is ongoing. In this review, we summarized and discussed the latest progress in genetic and epigenetic factors of NAFLD/MAFLD, in order to provide potential clues for MAFLD treatment.
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Affiliation(s)
- Xiaopeng Zhu
- Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
| | | | - Xin Gao
- Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan Institute for Metabolic Diseases, Fudan University, Shanghai, China
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Martínez-Montoro JI, Cornejo-Pareja I, Gómez-Pérez AM, Tinahones FJ. Impact of Genetic Polymorphism on Response to Therapy in Non-Alcoholic Fatty Liver Disease. Nutrients 2021; 13:4077. [PMID: 34836332 PMCID: PMC8625016 DOI: 10.3390/nu13114077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 12/13/2022] Open
Abstract
In the last decades, the global prevalence of non-alcoholic fatty liver disease (NAFLD) has reached pandemic proportions with derived major health and socioeconomic consequences; this tendency is expected to be further aggravated in the coming years. Obesity, insulin resistance/type 2 diabetes mellitus, sedentary lifestyle, increased caloric intake and genetic predisposition constitute the main risk factors associated with the development and progression of the disease. Importantly, the interaction between the inherited genetic background and some unhealthy dietary patterns has been postulated to have an essential role in the pathogenesis of NAFLD. Weight loss through lifestyle modifications is considered the cornerstone of the treatment for NAFLD and the inter-individual variability in the response to some dietary approaches may be conditioned by the presence of different single nucleotide polymorphisms. In this review, we summarize the current evidence on the influence of the association between genetic susceptibility and dietary habits in NAFLD pathophysiology, as well as the role of gene polymorphism in the response to lifestyle interventions and the potential interaction between nutritional genomics and other emerging therapies for NAFLD, such as bariatric surgery and several pharmacologic agents.
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Affiliation(s)
- José Ignacio Martínez-Montoro
- Department of Endocrinology and Nutrition, Virgen de la Victoria University Hospital, 29010 Málaga, Spain; (J.I.M.-M.); (F.J.T.)
- Faculty of Medicine, University of Málaga, 29071 Málaga, Spain
| | - Isabel Cornejo-Pareja
- Instituto de Investigación Biomédica de Málaga (IBIMA), Virgen de la Victoria University Hospital, 29010 Málaga, Spain
- Spanish Biomedical Research Center in Physiopathology of Obesity and Nutrition (CIBERObn), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Ana María Gómez-Pérez
- Department of Endocrinology and Nutrition, Virgen de la Victoria University Hospital, 29010 Málaga, Spain; (J.I.M.-M.); (F.J.T.)
| | - Francisco J. Tinahones
- Department of Endocrinology and Nutrition, Virgen de la Victoria University Hospital, 29010 Málaga, Spain; (J.I.M.-M.); (F.J.T.)
- Faculty of Medicine, University of Málaga, 29071 Málaga, Spain
- Instituto de Investigación Biomédica de Málaga (IBIMA), Virgen de la Victoria University Hospital, 29010 Málaga, Spain
- Spanish Biomedical Research Center in Physiopathology of Obesity and Nutrition (CIBERObn), Instituto de Salud Carlos III, 28029 Madrid, Spain
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6
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Meroni M, Longo M, Tria G, Dongiovanni P. Genetics Is of the Essence to Face NAFLD. Biomedicines 2021; 9:1359. [PMID: 34680476 PMCID: PMC8533437 DOI: 10.3390/biomedicines9101359] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 09/27/2021] [Indexed: 02/07/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is the commonest cause of chronic liver disease worldwide. It is closely related to obesity, insulin resistance (IR) and dyslipidemia so much so it is considered the hepatic manifestation of the Metabolic Syndrome. The NAFLD spectrum extends from simple steatosis to nonalcoholic steatohepatitis (NASH), a clinical condition which may progress up to fibrosis, cirrhosis and hepatocellular carcinoma (HCC). NAFLD is a complex disease whose pathogenesis is shaped by both environmental and genetic factors. In the last two decades, several heritable modifications in genes influencing hepatic lipid remodeling, and mitochondrial oxidative status have been emerged as predictors of progressive hepatic damage. Among them, the patatin-like phospholipase domain-containing 3 (PNPLA3) p.I148M, the Transmembrane 6 superfamily member 2 (TM6SF2) p.E167K and the rs641738 membrane bound-o-acyltransferase domain-containing 7 (MBOAT7) polymorphisms are considered the most robust modifiers of NAFLD. However, a forefront frontier in the study of NAFLD heritability is to postulate score-based strategy, building polygenic risk scores (PRS), which aggregate the most relevant genetic determinants of NAFLD and biochemical parameters, with the purpose to foresee patients with greater risk of severe NAFLD, guaranteeing the most highly predictive value, the best diagnostic accuracy and the more precise individualized therapy.
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Affiliation(s)
- Marica Meroni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Pad. Granelli, Via F Sforza 35, 20122 Milan, Italy; (M.M.); (M.L.); (G.T.)
| | - Miriam Longo
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Pad. Granelli, Via F Sforza 35, 20122 Milan, Italy; (M.M.); (M.L.); (G.T.)
- Department of Clinical Sciences and Community Health, Università Degli Studi di Milano, 20122 Milano, Italy
| | - Giada Tria
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Pad. Granelli, Via F Sforza 35, 20122 Milan, Italy; (M.M.); (M.L.); (G.T.)
| | - Paola Dongiovanni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Pad. Granelli, Via F Sforza 35, 20122 Milan, Italy; (M.M.); (M.L.); (G.T.)
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Chen LJ, Guo J, Zhang SX, Xu Y, Zhao Q, Zhang W, Xiao J, Chen Y. Sirtuin3 rs28365927 functional variant confers to the high risk of non-alcoholic fatty liver disease in Chinese Han population. Lipids Health Dis 2021; 20:92. [PMID: 34446002 PMCID: PMC8390275 DOI: 10.1186/s12944-021-01520-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 08/10/2021] [Indexed: 12/15/2022] Open
Abstract
Background Non-alcoholic fatty liver disease (NAFLD) is a multifactorial condition associated with aging, insulin resistance, metabolic syndrome, genetic factors and more. Although genetic traits are among the most important risks factors for NAFLD, the understanding of their influence is still quite limited. The present study aimed at identifying novel single nucleotide polymorphisms (SNPs) that may confer a risk for NAFLD in the Han Chinese population. Methods Based on the “two-hit hypothesis”, candidate SNPs, including Sirtuin3 rs28365927, were genotyped by MassARRAY in B-type ultrasonography-proven NAFLD patients (n = 292) and healthy controls (n = 387). Results In a model analysis of individuals matched based on gender and age that compared 223 NAFLD and 223 non-NAFLD patients, the rs28365927 GA + AA genotype was a significant risk factor for the development of NAFLD in a dominant model. Rs28365927 was significantly associated with a higher NAFLD risk in both an additive model (A vs G) and genotypic model (GA vs GG). Among the NAFLD patients, serum levels of total bilirubin (TBIL), DBIL direct bilirubin (DBIL) and glutamic-pyruvic transaminase (ALT) in rs28365927 A allele carriers (GA + AA) were 11.1, 14.7 and 41.5% higher, respectively, than in non-carriers (GG). Furthermore, among the NAFLD patients, the carriers of Rs28365927 allele A were positively correlated with higher ALT levels. Conclusion Sirtuin3 rs28365927 functional variant confers to the high risk of non-alcoholic fatty liver disease in Chinese Han population. The rs28365927 A allele significantly increased the ALT levels of NAFLD patients. Supplementary Information The online version contains supplementary material available at 10.1186/s12944-021-01520-x.
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Affiliation(s)
- Li-Jie Chen
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, P. R. China.,Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, China.,Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders, Changsha, Hunan, China
| | - Jing Guo
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, P. R. China.,Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, China.,Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders, Changsha, Hunan, China
| | - Song-Xia Zhang
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, P. R. China.,Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, China.,Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders, Changsha, Hunan, China
| | - Ying Xu
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, P. R. China.,Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, China.,Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders, Changsha, Hunan, China
| | - Qing Zhao
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, P. R. China.,Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, China.,Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders, Changsha, Hunan, China
| | - Wei Zhang
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, P. R. China.,Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, China.,Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha, Hunan, China.,National Clinical Research Center for Geriatric Disorders, Changsha, Hunan, China
| | - Jian Xiao
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Yao Chen
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, P. R. China. .,Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, China. .,Engineering Research Center of Applied Technology of Pharmacogenomics, Ministry of Education, Changsha, Hunan, China. .,National Clinical Research Center for Geriatric Disorders, Changsha, Hunan, China.
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8
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Pafili K, Roden M. Nonalcoholic fatty liver disease (NAFLD) from pathogenesis to treatment concepts in humans. Mol Metab 2021; 50:101122. [PMID: 33220492 PMCID: PMC8324683 DOI: 10.1016/j.molmet.2020.101122] [Citation(s) in RCA: 142] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/30/2020] [Accepted: 11/13/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Nonalcoholic fatty liver disease (NAFLD) comprises hepatic alterations with increased lipid accumulation (steatosis) without or with inflammation (nonalcoholic steatohepatitis, NASH) and/or fibrosis in the absence of other causes of liver disease. NAFLD is developing as a burgeoning health challenge, mainly due to the worldwide obesity and diabetes epidemics. SCOPE OF REVIEW This review summarizes the knowledge on the pathogenesis underlying NAFLD by focusing on studies in humans and on hypercaloric nutrition, including effects of saturated fat and fructose, as well as adipose tissue dysfunction, leading to hepatic lipotoxicity, abnormal mitochondrial function, and oxidative stress, and highlights intestinal dysbiosis. These mechanisms are discussed in the context of current treatments targeting metabolic pathways and the results of related clinical trials. MAJOR CONCLUSIONS Recent studies have provided evidence that certain conditions, for example, the severe insulin-resistant diabetes (SIRD) subgroup (cluster) and the presence of an increasing number of gene variants, seem to predispose for excessive risk of NAFLD and its accelerated progression. Recent clinical trials have been frequently unsuccessful in halting or preventing NAFLD progression, perhaps partly due to including unselected cohorts in later stages of NAFLD. On the basis of this literature review, this study proposed screening in individuals with the highest genetic or acquired risk of disease progression, for example, the SIRD subgroup, and developing treatment concepts targeting the earliest pathophysiolgical alterations, namely, adipocyte dysfunction and insulin resistance.
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Affiliation(s)
- Kalliopi Pafili
- Institute of Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Düsseldorf, Germany; German Center for Diabetes Research, München-Neuherberg, Germany
| | - Michael Roden
- Institute of Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Düsseldorf, Germany; German Center for Diabetes Research, München-Neuherberg, Germany; Division of Endocrinology and Diabetology, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany.
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9
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Brahma MK, Gilglioni EH, Zhou L, Trépo E, Chen P, Gurzov EN. Oxidative stress in obesity-associated hepatocellular carcinoma: sources, signaling and therapeutic challenges. Oncogene 2021; 40:5155-5167. [PMID: 34290399 PMCID: PMC9277657 DOI: 10.1038/s41388-021-01950-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 07/01/2021] [Accepted: 07/08/2021] [Indexed: 02/06/2023]
Abstract
Obesity affects more than 650 million individuals worldwide and is a well-established risk factor for the development of hepatocellular carcinoma (HCC). Oxidative stress can be considered as a bona fide tumor promoter, contributing to the initiation and progression of liver cancer. Indeed, one of the key events involved in HCC progression is excessive levels of reactive oxygen species (ROS) resulting from the fatty acid influx and chronic inflammation. This review provides insights into the different intracellular sources of obesity-induced ROS and molecular mechanisms responsible for hepatic tumorigenesis. In addition, we highlight recent findings pointing to the role of the dysregulated activity of BCL-2 proteins and protein tyrosine phosphatases (PTPs) in the generation of hepatic oxidative stress and ROS-mediated dysfunctional signaling, respectively. Finally, we discuss the potential and challenges of novel nanotechnology strategies to prevent ROS formation in obesity-associated HCC.
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Affiliation(s)
- Manoja K Brahma
- Signal Transduction and Metabolism Laboratory, Laboratoire de Gastroentérologie Expérimental et Endotools, Université libre de Bruxelles, Brussels, Belgium
| | - Eduardo H Gilglioni
- Signal Transduction and Metabolism Laboratory, Laboratoire de Gastroentérologie Expérimental et Endotools, Université libre de Bruxelles, Brussels, Belgium
| | - Lang Zhou
- Materials Research and Education Center, Auburn University, Auburn, AL, 36849, United States
| | - Eric Trépo
- Department of Gastroenterology, Hepatopancreatology and Digestive Oncology, C.U.B. Hôpital Erasme, Université libre de Bruxelles, Brussels, Belgium
- Laboratory of Experimental Gastroenterology, Université libre de Bruxelles, Brussels, Belgium
| | - Pengyu Chen
- Materials Research and Education Center, Auburn University, Auburn, AL, 36849, United States
| | - Esteban N Gurzov
- Signal Transduction and Metabolism Laboratory, Laboratoire de Gastroentérologie Expérimental et Endotools, Université libre de Bruxelles, Brussels, Belgium.
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Dallio M, Romeo M, Gravina AG, Masarone M, Larussa T, Abenavoli L, Persico M, Loguercio C, Federico A. Nutrigenomics and Nutrigenetics in Metabolic- (Dysfunction) Associated Fatty Liver Disease: Novel Insights and Future Perspectives. Nutrients 2021; 13:nu13051679. [PMID: 34063372 PMCID: PMC8156164 DOI: 10.3390/nu13051679] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 05/12/2021] [Accepted: 05/13/2021] [Indexed: 12/12/2022] Open
Abstract
Metabolic- (dysfunction) associated fatty liver disease (MAFLD) represents the predominant hepatopathy and one of the most important systemic, metabolic-related disorders all over the world associated with severe medical and socio-economic repercussions due to its growing prevalence, clinical course (steatohepatitis and/or hepatocellular-carcinoma), and related extra-hepatic comorbidities. To date, no specific medications for the treatment of this condition exist, and the most valid recommendation for patients remains lifestyle change. MAFLD has been associated with metabolic syndrome; its development and progression are widely influenced by the interplay between genetic, environmental, and nutritional factors. Nutrigenetics and nutrigenomics findings suggest nutrition’s capability, by acting on the individual genetic background and modifying the specific epigenetic expression as well, to influence patients’ clinical outcome. Besides, immunity response is emerging as pivotal in this multifactorial scenario, suggesting the interaction between diet, genetics, and immunity as another tangled network that needs to be explored. The present review describes the genetic background contribution to MAFLD onset and worsening, its possibility to be influenced by nutritional habits, and the interplay between nutrients and immunity as one of the most promising research fields of the future in this context.
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Affiliation(s)
- Marcello Dallio
- Department of Precision Medicine, University of Campania Luigi Vanvitelli, Via S. Pansini 5, 80131 Naples, Italy; (M.R.); (A.G.G.); (C.L.); (A.F.)
- Correspondence: ; Tel.: +39-0815666740
| | - Mario Romeo
- Department of Precision Medicine, University of Campania Luigi Vanvitelli, Via S. Pansini 5, 80131 Naples, Italy; (M.R.); (A.G.G.); (C.L.); (A.F.)
| | - Antonietta Gerarda Gravina
- Department of Precision Medicine, University of Campania Luigi Vanvitelli, Via S. Pansini 5, 80131 Naples, Italy; (M.R.); (A.G.G.); (C.L.); (A.F.)
| | - Mario Masarone
- Department of Medicine and Surgery, University of Salerno, Via Allende, 84081 Baronissi, Italy; (M.M.); (M.P.)
| | - Tiziana Larussa
- Department of Health Sciences, University Magna Graecia, viale Europa, 88100 Catanzaro, Italy; (T.L.); (L.A.)
| | - Ludovico Abenavoli
- Department of Health Sciences, University Magna Graecia, viale Europa, 88100 Catanzaro, Italy; (T.L.); (L.A.)
| | - Marcello Persico
- Department of Medicine and Surgery, University of Salerno, Via Allende, 84081 Baronissi, Italy; (M.M.); (M.P.)
| | - Carmelina Loguercio
- Department of Precision Medicine, University of Campania Luigi Vanvitelli, Via S. Pansini 5, 80131 Naples, Italy; (M.R.); (A.G.G.); (C.L.); (A.F.)
| | - Alessandro Federico
- Department of Precision Medicine, University of Campania Luigi Vanvitelli, Via S. Pansini 5, 80131 Naples, Italy; (M.R.); (A.G.G.); (C.L.); (A.F.)
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11
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Longo M, Paolini E, Meroni M, Dongiovanni P. Remodeling of Mitochondrial Plasticity: The Key Switch from NAFLD/NASH to HCC. Int J Mol Sci 2021; 22:4173. [PMID: 33920670 PMCID: PMC8073183 DOI: 10.3390/ijms22084173] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/15/2021] [Accepted: 04/16/2021] [Indexed: 02/06/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver and the third-leading cause of cancer-related mortality. Currently, the global burden of nonalcoholic fatty liver disease (NAFLD) has dramatically overcome both viral and alcohol hepatitis, thus becoming the main cause of HCC incidence. NAFLD pathogenesis is severely influenced by lifestyle and genetic predisposition. Mitochondria are highly dynamic organelles that may adapt in response to environment, genetics and epigenetics in the liver ("mitochondrial plasticity"). Mounting evidence highlights that mitochondrial dysfunction due to loss of mitochondrial flexibility may arise before overt NAFLD, and from the early stages of liver injury. Mitochondrial failure promotes not only hepatocellular damage, but also release signals (mito-DAMPs), which trigger inflammation and fibrosis, generating an adverse microenvironment in which several hepatocytes select anti-apoptotic programs and mutations that may allow survival and proliferation. Furthermore, one of the key events in malignant hepatocytes is represented by the remodeling of glucidic-lipidic metabolism combined with the reprogramming of mitochondrial functions, optimized to deal with energy demand. In sum, this review will discuss how mitochondrial defects may be translated into causative explanations of NAFLD-driven HCC, emphasizing future directions for research and for the development of potential preventive or curative strategies.
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Affiliation(s)
- Miriam Longo
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Pad. Granelli, Via F Sforza 35, 20122 Milan, Italy; (M.L.); (E.P.); (M.M.)
- Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Via Francesco Sforza 35, 20122 Milano, Italy
| | - Erika Paolini
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Pad. Granelli, Via F Sforza 35, 20122 Milan, Italy; (M.L.); (E.P.); (M.M.)
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via Balzaretti 9, 20133 Milano, Italy
| | - Marica Meroni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Pad. Granelli, Via F Sforza 35, 20122 Milan, Italy; (M.L.); (E.P.); (M.M.)
| | - Paola Dongiovanni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Pad. Granelli, Via F Sforza 35, 20122 Milan, Italy; (M.L.); (E.P.); (M.M.)
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12
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Longo M, Meroni M, Paolini E, Macchi C, Dongiovanni P. Mitochondrial dynamics and nonalcoholic fatty liver disease (NAFLD): new perspectives for a fairy-tale ending? Metabolism 2021; 117:154708. [PMID: 33444607 DOI: 10.1016/j.metabol.2021.154708] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 01/05/2021] [Accepted: 01/07/2021] [Indexed: 12/12/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) includes a broad spectrum of liver dysfunctions and it is predicted to become the primary cause of liver failure and hepatocellular carcinoma. Mitochondria are highly dynamic organelles involved in multiple metabolic/bioenergetic pathways in the liver. Emerging evidence outlined that hepatic mitochondria adapt in number and functionality in response to external cues, as high caloric intake and obesity, by modulating mitochondrial biogenesis, and maladaptive mitochondrial response has been described from the early stages of NAFLD. Indeed, mitochondrial plasticity is lost in progressive NAFLD and these organelles may assume an aberrant phenotype to drive or contribute to hepatocarcinogenesis. Severe alimentary regimen and physical exercise represent the cornerstone for NAFLD care, although the low patients' compliance is urging towards the discovery of novel pharmacological treatments. Mitochondrial-targeted drugs aimed to recover mitochondrial lifecycle and to modulate oxidative stress are becoming attractive molecules to be potentially introduced for NAFLD management. Although the path guiding the switch from bench to bedside remains tortuous, the study of mitochondrial dynamics is providing intriguing perspectives for future NAFLD healthcare.
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Affiliation(s)
- Miriam Longo
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Pad. Granelli, via F Sforza 35, 20122 Milan, Italy; Department of Clinical Sciences and Community Health, Università degli Studi di Milano, 20122 Milano, Italy
| | - Marica Meroni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Pad. Granelli, via F Sforza 35, 20122 Milan, Italy; Department of Pathophysiology and Transplantation, Università degli Studi di Milano, 20122 Milano, Italy
| | - Erika Paolini
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Pad. Granelli, via F Sforza 35, 20122 Milan, Italy; Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20133 Milano, Italy
| | - Chiara Macchi
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20133 Milano, Italy
| | - Paola Dongiovanni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Pad. Granelli, via F Sforza 35, 20122 Milan, Italy.
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13
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Bianco C, Casirati E, Malvestiti F, Valenti L. Genetic predisposition similarities between NASH and ASH: Identification of new therapeutic targets. JHEP Rep 2021; 3:100284. [PMID: 34027340 PMCID: PMC8122117 DOI: 10.1016/j.jhepr.2021.100284] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 03/09/2021] [Accepted: 03/15/2021] [Indexed: 12/12/2022] Open
Abstract
Fatty liver disease can be triggered by a combination of excess alcohol, dysmetabolism and other environmental cues, which can lead to steatohepatitis and can evolve to acute/chronic liver failure and hepatocellular carcinoma, especially in the presence of shared inherited determinants. The recent identification of the genetic causes of steatohepatitis is revealing new avenues for more effective risk stratification. Discovery of the mechanisms underpinning the detrimental effect of causal mutations has led to some breakthroughs in the comprehension of the pathophysiology of steatohepatitis. Thanks to this approach, hepatocellular fat accumulation, altered lipid droplet remodelling and lipotoxicity have now taken centre stage, while the role of adiposity and gut-liver axis alterations have been independently validated. This process could ignite a virtuous research cycle that, starting from human genomics, through omics approaches, molecular genetics and disease models, may lead to the development of new therapeutics targeted to patients at higher risk. Herein, we also review how this knowledge has been applied to: a) the study of the main PNPLA3 I148M risk variant, up to the stage of the first in-human therapeutic trials; b) highlight a role of MBOAT7 downregulation and lysophosphatidyl-inositol in steatohepatitis; c) identify IL-32 as a candidate mediator linking lipotoxicity to inflammation and liver disease. Although this precision medicine drug discovery pipeline is mainly being applied to non-alcoholic steatohepatitis, there is hope that successful products could be repurposed to treat alcohol-related liver disease as well.
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Key Words
- AA, arachidonic acid
- ASH, alcoholic steatohepatitis
- DAG, diacylglycerol
- DNL, de novo lipogenesis
- ER, endoplasmic reticulum
- FFAs, free fatty acids
- FGF19, fibroblast growth factor 19
- FLD, fatty liver disease
- FXR, farnesoid X receptor
- GCKR, glucokinase regulator
- GPR55, G protein-coupled receptor 55
- HCC, hepatocellular carcinoma
- HFE, homeostatic iron regulator
- HSC, hepatic stellate cells
- HSD17B13, hydroxysteroid 17-beta dehydrogenase 13
- IL-, interleukin-
- IL32
- LDs, lipid droplets
- LPI, lysophosphatidyl-inositol
- MARC1, mitochondrial amidoxime reducing component 1
- MBOAT7
- MBOAT7, membrane bound O-acyltransferase domain-containing 7
- NASH, non-alcoholic steatohepatitis
- PNPLA3
- PNPLA3, patatin like phospholipase domain containing 3
- PPAR, peroxisome proliferator-activated receptor
- PRS, polygenic risk score
- PUFAs, polyunsaturated fatty acids
- SREBP, sterol response element binding protein
- TAG, triacylglycerol
- TNF-α, tumour necrosis factor-α
- alcoholic liver disease
- cirrhosis
- fatty liver disease
- genetics
- interleukin-32
- non-alcoholic fatty liver disease
- precision medicine
- steatohepatitis
- therapy
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Affiliation(s)
- Cristiana Bianco
- Precision Medicine - Department of Transfusion Medicine and Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Elia Casirati
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Francesco Malvestiti
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Luca Valenti
- Precision Medicine - Department of Transfusion Medicine and Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
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14
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Choudhary NS, Duseja A. Genetic and epigenetic disease modifiers: non-alcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD). Transl Gastroenterol Hepatol 2021; 6:2. [PMID: 33409397 DOI: 10.21037/tgh.2019.09.06] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Accepted: 09/04/2019] [Indexed: 12/12/2022] Open
Abstract
Inter-individual and inter-ethnic differences and difference in the severity and progression of liver disease among patients with non-alcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD) suggests the involvement of genetic and epigenetic factors in their pathogenesis. This article reviews the genetic and epigenetic modifiers in patients with NAFLD and ALD. Evidence regarding the genetic and epigenetic disease modifiers of NAFLD and ALD was reviewed by searching the available literature. Both genome wide association studies (GWAS) and candidate gene studies pertaining to the pathogenesis in both diseases were included. Clinical implications of the available information are also discussed. Several studies have shown association of both NAFLD and ALD with I148M PNPLA3 variant. In addition to the higher prevalence of hepatic steatosis, the I148M PNPLA3 variant is also associated with severity of liver disease and risk of hepatocellular carcinoma (HCC). TM6SF2 is the other genetic variant shown to be significantly associated with hepatic steatosis and cirrhosis in patients with NAFLD and ALD. The Membrane bound O-acyltransferase domain-containing 7 (MBOAT7) genetic variant is also associated with both NAFLD and ALD. In addition to these mutations, several variants related to the genes involved in glucose metabolism, insulin resistance, lipid metabolism, oxidative stress, inflammatory pathways, fibrosis have also been shown to be the disease modifiers in patients with NAFLD and ALD. Epigenetics involving several micro RNAs and DNA methylation could also modify the disease course in NAFLD and ALD. In conclusion the available literature suggests that genetics and epigenetics are involved in the pathogenesis of NAFLD and ALD which may affect the disease prevalence, severity and response to treatment in these patients.
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Affiliation(s)
- Narendra Singh Choudhary
- Institute of Liver Transplantation and Regenerative Medicine, Medanta, The Medicity, Gurgaon, Delhi (NCR), India
| | - Ajay Duseja
- Department of Hepatology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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15
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Meroni M, Longo M, Dongiovanni P. Genetic and metabolic factors: the perfect combination to treat metabolic associated fatty liver disease. EXPLORATION OF MEDICINE 2020. [DOI: 10.37349/emed.2020.00015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The prevalence of nonalcoholic or more recently re-defined metabolic associated fatty liver disease (MAFLD) is rapidly growing worldwide. It is characterized by hepatic fat accumulation exceeding 5% of liver weight not attributable to alcohol consumption. MAFLD refers to an umbrella of conditions ranging from simple steatosis to nonalcoholic steatohepatitis which may finally progress to cirrhosis and hepatocellular carcinoma. MAFLD is closely related to components of the metabolic syndrome and to environmental factors. In addition to the latter, genetic predisposition plays a key role in MAFLD pathogenesis and strictly contributes to its progressive forms. The candidate genes which have been related to MAFLD hereditability are mainly involved in lipids remodeling, lipid droplets assembly, lipoprotein packaging and secretion, de novo lipogenesis, and mitochondrial redox status. In the recent years, it has emerged the opportunity to translate the genetics into clinics by aggregating the genetic variants mostly associated with MAFLD in polygenic risk scores. These scores might be used in combination with metabolic factors to identify those patients at higher risk to develop more severe liver disease and to schedule an individual therapeutic approach.
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Affiliation(s)
- Marica Meroni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milano, Italy; Department of Pathophysiology and Transplantation, Università degli Studi di Milano, 20122 Milano, Italy
| | - Miriam Longo
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milano, Italy; Department of Clinical Sciences and Community Health, Università degli Studi di Milano, 20122 Milano, Italy
| | - Paola Dongiovanni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milano, Italy
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16
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Botello-Manilla AE, Chávez-Tapia NC, Uribe M, Nuño-Lámbarri N. Genetics and epigenetics purpose in nonalcoholic fatty liver disease. Expert Rev Gastroenterol Hepatol 2020; 14:733-748. [PMID: 32552211 DOI: 10.1080/17474124.2020.1780915] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION nonalcoholic fatty liver disease (NAFLD) comprises a broad spectrum of diseases, which can progress from benign steatosis to nonalcoholic steatohepatitis, liver cirrhosis and hepatocellular carcinoma. NAFLD is the most common chronic liver disease in developed countries, affecting approximately 25% of the general population. Insulin resistance, adipose tissue dysfunction, mitochondrial and endoplasmic reticulum stress, chronic inflammation, genetic and epigenetic factors are NAFLD triggers that control the disease susceptibility and progression. AREAS COVERED In recent years a large number of investigations have been carried out to elucidate genetic and epigenetic factors in the disease pathogenesis, as well as the search for diagnostic markers and therapeutic targets. This paper objective is to report the most studied genetic and epigenetic variants around NAFLD. EXPERT OPINION NAFLD lead to various comorbidities, which have a considerable impact on the patient wellness and life quality, as well as on the costs they generate for the country's health services. It is essential to continue with molecular research, since it could be used as a clinical tool for prognosis and disease severity. Specifically, in the field of hepatology, plasma miRNAs could provide a novel tool in liver diseases diagnosis and monitoring, representing an alternative to invasive diagnostic procedures.
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Affiliation(s)
| | - Norberto Carlos Chávez-Tapia
- Traslational Research Unit, Médica Sur Clinic & Foundation , Mexico City, Mexico.,Obesity and Digestive Diseases Unit, Médica Sur Clinic & Foundation , Mexico City, Mexico
| | - Misael Uribe
- Obesity and Digestive Diseases Unit, Médica Sur Clinic & Foundation , Mexico City, Mexico
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17
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Novo E, Bocca C, Foglia B, Protopapa F, Maggiora M, Parola M, Cannito S. Liver fibrogenesis: un update on established and emerging basic concepts. Arch Biochem Biophys 2020; 689:108445. [PMID: 32524998 DOI: 10.1016/j.abb.2020.108445] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 05/20/2020] [Accepted: 05/28/2020] [Indexed: 02/06/2023]
Abstract
Liver fibrogenesis is defined as a dynamic and highly integrated process occurring during chronic injury to liver parenchyma that can result in excess deposition of extracellular matrix (ECM) components (i.e., liver fibrosis). Liver fibrogenesis, together with chronic inflammatory response, is then primarily involved in the progression of chronic liver diseases (CLD) irrespective of the specific etiology. In the present review we will first offer a synthetic and updated overview of major basic concepts in relation to the role of myofibroblasts (MFs), macrophages and other hepatic cell populations involved in CLD to then offer an overview of established and emerging issues and mechanisms that have been proposed to favor and/or promote CLD progression. A special focus will be dedicated to selected issues that include emerging features in the field of cholangiopathies, the emerging role of genetic and epigenetic factors as well as of hypoxia, hypoxia-inducible factors (HIFs) and related mediators.
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Affiliation(s)
- Erica Novo
- University of Torino, Dept. Clinical and Biological Sciences, Unit of Experimental Medicine and Clinical Pathology, Corso Raffaello 30, 10125, Torino, Italy
| | - Claudia Bocca
- University of Torino, Dept. Clinical and Biological Sciences, Unit of Experimental Medicine and Clinical Pathology, Corso Raffaello 30, 10125, Torino, Italy
| | - Beatrice Foglia
- University of Torino, Dept. Clinical and Biological Sciences, Unit of Experimental Medicine and Clinical Pathology, Corso Raffaello 30, 10125, Torino, Italy
| | - Francesca Protopapa
- University of Torino, Dept. Clinical and Biological Sciences, Unit of Experimental Medicine and Clinical Pathology, Corso Raffaello 30, 10125, Torino, Italy
| | - Marina Maggiora
- University of Torino, Dept. Clinical and Biological Sciences, Unit of Experimental Medicine and Clinical Pathology, Corso Raffaello 30, 10125, Torino, Italy
| | - Maurizio Parola
- University of Torino, Dept. Clinical and Biological Sciences, Unit of Experimental Medicine and Clinical Pathology, Corso Raffaello 30, 10125, Torino, Italy.
| | - Stefania Cannito
- University of Torino, Dept. Clinical and Biological Sciences, Unit of Experimental Medicine and Clinical Pathology, Corso Raffaello 30, 10125, Torino, Italy
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18
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Trépo E, Valenti L. Update on NAFLD genetics: From new variants to the clinic. J Hepatol 2020; 72:1196-1209. [PMID: 32145256 DOI: 10.1016/j.jhep.2020.02.020] [Citation(s) in RCA: 218] [Impact Index Per Article: 54.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 02/04/2020] [Accepted: 02/13/2020] [Indexed: 02/07/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the leading cause of liver diseases in high-income countries and the burden of NAFLD is increasing at an alarming rate. The risk of developing NAFLD and related complications is highly variable among individuals and is determined by environmental and genetic factors. Genome-wide association studies have uncovered robust and reproducible associations between variations in genes such as PNPLA3, TM6SF2, MBOAT7, GCKR, HSD17B13 and the natural history of NAFLD. These findings have provided compelling new insights into the biology of NAFLD and highlighted potentially attractive pharmaceutical targets. More recently the development of polygenic risk scores, which have shown promising results for the clinical risk prediction of other complex traits (such as cardiovascular disease and breast cancer), have provided new impetus for the clinical validation of genetic variants in NAFLD risk stratification. Herein, we review current knowledge on the genetic architecture of NAFLD, including gene-environment interactions, and discuss the implications for disease pathobiology, drug discovery and risk prediction. We particularly focus on the potential clinical translation of recent genetic advances, discussing methodological hurdles that must be overcome before these discoveries can be implemented in everyday practice.
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Affiliation(s)
- Eric Trépo
- Department of Gastroenterology, Hepatopancreatology and Digestive Oncology, C.U.B. Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium; Laboratory of Experimental Gastroenterology, Université Libre de Bruxelles, Brussels, Belgium.
| | - Luca Valenti
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy; Translational Medicine - Department of Transfusion Medicine and Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.
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19
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Chandrasekharan K, Alazawi W. Genetics of Non-Alcoholic Fatty Liver and Cardiovascular Disease: Implications for Therapy? Front Pharmacol 2020; 10:1413. [PMID: 31969816 PMCID: PMC6960381 DOI: 10.3389/fphar.2019.01413] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 11/07/2019] [Indexed: 12/16/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. The most common cause of mortality in NAFLD is cardiovascular disease (CVD), and a key of focus in drug development is to discover therapies that target both liver injury and CVD risk. NAFLD and CVD are complex disease spectra with complex heritability patterns. Nevertheless, genome wide association studies and meta-analyses of these have identified genetic loci that are associated with increased risk of relevant pathological features of disease or clinical endpoints. This review focuses on the genetic risk loci identified in the NAFLD spectrum and asks whether any of these are also risk factors for CVD. Surprisingly, given the shared co-morbidities and risk factors, little robust evidence exists that NAFLD and CVD share genetic risk. Despite this, therapeutic intervention that targets both liver disease and CVD remains an important clinical need and a major focus for pharmaceutical development.
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Affiliation(s)
- Karthik Chandrasekharan
- Barts Liver Centre, Blizard Institute, Queen Mary University of London, London, United Kingdom
| | - William Alazawi
- Barts Liver Centre, Blizard Institute, Queen Mary University of London, London, United Kingdom
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20
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Samji NS, Verma R, Keri KC, Singal AK, Ahmed A, Rinella M, Bernstein D, Abdelmalek MF, Satapathy SK. Liver Transplantation for Nonalcoholic Steatohepatitis: Pathophysiology of Recurrence and Clinical Challenges. Dig Dis Sci 2019; 64:3413-3430. [PMID: 31312990 DOI: 10.1007/s10620-019-05716-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Accepted: 07/02/2019] [Indexed: 02/08/2023]
Abstract
Nonalcoholic steatohepatitis is the fastest-growing indication for the liver transplant and a leading cause of hepatocellular carcinoma among patients listed for liver transplantation in the USA. Post-transplant nonalcoholic hepatic steatosis and steatohepatitis are frequent complications of liver transplantation. Nonalcoholic steatohepatitis poses a significant challenge in both pre- and post-transplant period due to its association with metabolic syndrome, coronary artery disease, chronic kidney disease, and obstructive sleep apnea. While optimal therapy is not yet available in the post-liver transplant setting, lifestyle interventions continue to remain as the mainstay of therapy for post-transplant nonalcoholic steatohepatitis. Early recognition with protocol biopsies and noninvasive modalities, along with modification of known risk factors, are the most effective methods to curtail the progression of nonalcoholic steatohepatitis in the absence of FDA-approved pharmacologic therapy.
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Affiliation(s)
- Naga Swetha Samji
- Tennova Cleveland Hospital, 2305 Chambliss Ave NW, Cleveland, TN, 37311, USA
| | - Rajanshu Verma
- Division of Transplant Surgery, Department of Surgery, Methodist University Hospital Transplant Institute, University of Tennessee Health Sciences Center, Memphis, TN, USA
| | | | - Ashwani K Singal
- University of South Dakota Sanford School of Medicine, Avera Transplant Institute, S. Cliff Ave, Sioux Falls, SD, 57105, USA
| | - Aijaz Ahmed
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, CA, USA
| | - Mary Rinella
- Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - David Bernstein
- Division of Hepatology and Sandra Atlas Bass Center for Liver Diseases, Northwell Health, Manhasset, NY, USA
| | - Manal F Abdelmalek
- Division of Gastroenterology/Hepatology, Duke University, 40 Duke Medicine Cir, Durham, NC, USA
| | - Sanjaya K Satapathy
- Division of Hepatology at Sandra Atlas Bass Center for Liver Diseases and Transplantation, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Health, 400 Community Drive, Manhasset, NY, 11030, USA.
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21
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Taliento AE, Dallio M, Federico A, Prati D, Valenti L. Novel Insights into the Genetic Landscape of Nonalcoholic Fatty Liver Disease. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:E2755. [PMID: 31375010 PMCID: PMC6695718 DOI: 10.3390/ijerph16152755] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 07/27/2019] [Accepted: 07/30/2019] [Indexed: 12/19/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD), the most common liver disorder worldwide, is epidemiologically associated with overweight, insulin resistance features and type 2 diabetes, and can progress to advanced liver fibrosis and hepatocellular carcinoma. Genetic factors play an important role in the development of NAFLD, which is a multifactorial disease. Several common naturally occurring variants modulating lipid and retinol metabolism in hepatocytes predispose to NAFLD development and progression, in particular those in PNPLA3, TM6SF2, MBOAT7, and HSD17B13. In addition, genetic variants that protect hepatic cells from oxidative stress modulate the susceptibility to progressive NAFLD. Although the molecular mechanisms linking these genetic variants with liver disease are not yet fully understood, hepatic fat has emerged as a major driver of the disease, while altered retinol metabolism and mitochondrial oxidative stress play a role in determining the development of advanced NAFLD.
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Affiliation(s)
- Alice Emma Taliento
- Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico IRCCS, 20122 Milan, Italy
| | - Marcello Dallio
- Department of Precision Medicine, University of Campania "Luigi Vanvitelli", 80131 Naples, Italy.
| | - Alessandro Federico
- Department of Precision Medicine, University of Campania "Luigi Vanvitelli", 80131 Naples, Italy
| | - Daniele Prati
- Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico IRCCS, 20122 Milan, Italy
| | - Luca Valenti
- Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico IRCCS, 20122 Milan, Italy.
- Department of Pathophysiology and Transplantation, University of Milan, 20122 Milano, Italy.
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22
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Dong J, Im YR, Mann JP. Insights into paediatric non-alcoholic fatty liver disease from genetic variants. Liver Int 2019; 39:440-445. [PMID: 30615260 DOI: 10.1111/liv.14020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Affiliation(s)
- Jiawen Dong
- School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Yu Ri Im
- School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Jake P Mann
- Metabolic Research Laboratories-Institute of Metabolic Science, University of Cambridge, Cambridge, UK.,Department of Paediatrics, University of Cambridge, Cambridge, UK
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23
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Baker PR, Friedman JE. Mitochondrial role in the neonatal predisposition to developing nonalcoholic fatty liver disease. J Clin Invest 2018; 128:3692-3703. [PMID: 30168806 DOI: 10.1172/jci120846] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a global epidemic in obese children and adults, and the onset might have fetal origins. A growing body of evidence supports the role of developmental programming, whereby the maternal environment affects fetal and infant development, altering the risk profile for disease later in life. Human and nonhuman primate studies of maternal obesity demonstrate that risk factors for pediatric obesity and NAFLD begin in utero. The pathologic mechanisms for NAFLD are multifactorial but have centered on altered mitochondrial function/dysfunction that might precede insulin resistance. Compared with the adult liver, the fetal liver has fewer mitochondria, low activity of the fatty acid metabolic enzyme carnitine palmitoyl-CoA transferase-1, and little or no gluconeogenesis. Exposure to excess maternal fuels during fetal life uniquely alters hepatic fatty acid oxidation, tricarboxylic acid cycle activity, de novo lipogenesis, and mitochondrial health. These events promote increased oxidative stress and excess triglyceride storage, and, together with altered immune function and epigenetic changes, they prime the fetal liver for NAFLD and might drive the risk for nonalcoholic steatohepatitis in the next generation.
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Affiliation(s)
- Peter R Baker
- Section of Clinical Genetics and Metabolism, Department of Pediatrics
| | - Jacob E Friedman
- Section of Neonatology, Department of Pediatrics.,Department of Biochemistry and Molecular Genetics, and.,Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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24
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Wang JZ, Cao HX, Chen JN, Pan Q. PNPLA3 rs738409 underlies treatment response in nonalcoholic fatty liver disease. World J Clin Cases 2018; 6:167-175. [PMID: 30148144 PMCID: PMC6107533 DOI: 10.12998/wjcc.v6.i8.167] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 05/16/2018] [Accepted: 06/08/2018] [Indexed: 02/05/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) has now become the leading cause of chronic liver disease with its growing incidence worldwide. Patatin-like phospholipase domain-containing protein 3 (PNPLA3) rs738409 C > G reflects one of the critical genetic factors that confers high-risk to NAFLD. However, the role of PNPLA3 polymorphism in NAFLD treatment remains uncertain. Here, the present review reveals that NAFLD patients with G-allele at PNPLA3 rs738409 (PNPLA3 148M variant) are sensitive to therapies of lifestyle modification, dipeptidyl peptidase-4 inhibitors, and bariatric surgery. They exhibit much significant reduction of liver fat content, in concurrence with weigh loss and abolished insulin resistance, as compared to those of C-allele carriers. In contrast, patients bearing PNPLA3 rs738409 C-allele (PNPLA3 148I variant), instead of G-allele, demonstrate greater beneficial effects by omega-3 poly-unsaturated fatty acids and statin intervention. Improved adipose tissue-liver interaction and decrease in intrahepatic triglyceride efflux may contribute to the PNPLA3 rs738409 related diversities in therapeutic efficacy. Therefore, PNPLA3 rs738409 underlies the response to a variety of treatments, which warrants a personalized, precise medicine in NAFLD on the basis of genotype stratification.
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Affiliation(s)
- Jin-Zhi Wang
- Department of Gastroenterology, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
| | - Hai-Xia Cao
- Department of Gastroenterology, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
| | - Jian-Neng Chen
- Department of Hepatology, Zhengxing Hospital, Zhangzhou 363000, Fujian Province, China
| | - Qin Pan
- Department of Gastroenterology, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
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25
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Danford CJ, Yao ZM, Jiang ZG. Non-alcoholic fatty liver disease: a narrative review of genetics. J Biomed Res 2018; 32:389-400. [PMID: 30355853 PMCID: PMC6283828 DOI: 10.7555/jbr.32.20180045] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is now the most common cause of chronic liver diseases worldwide. It encompasses a spectrum of disorders ranging from isolated hepatic steatosis to nonalcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and hepatocellular carcinoma. One of the key challenges in NAFLD is identifying which patients will progress. Epidemiological and genetic studies indicate a strong pattern of heritability that may explain some of the variability in NAFLD phenotype and risk of progression. To date, at least three common genetic variants in the PNPLA3, TM6SF2, and GCKR genes have been robustly linked to NAFLD in the population. The function of these genes revealed novel pathways implicated in both the development and progression of NAFLD. In addition, candidate genes previously implicated in NAFLD pathogenesis have also been identified as determinants or modulators of NAFLD phenotype including genes involved in hepatocellular lipid handling, insulin resistance, inflammation, and fibrogenesis. This article will review the current understanding of the genetics underpinning the development of hepatic steatosis and the progression of NASH. These newly acquired insights may transform our strategy to risk-stratify patients with NAFLD and to identify new potential therapeutic targets.
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Affiliation(s)
- Christopher J Danford
- Division of Gastroenterology and Hepatology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
| | - Ze-Min Yao
- Department of Biochemistry, Microbiology and Immunology, Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Z Gordon Jiang
- Division of Gastroenterology and Hepatology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
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Schuster S, Cabrera D, Arrese M, Feldstein AE. Triggering and resolution of inflammation in NASH. Nat Rev Gastroenterol Hepatol 2018; 15:349-364. [PMID: 29740166 DOI: 10.1038/s41575-018-0009-6] [Citation(s) in RCA: 531] [Impact Index Per Article: 88.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Nonalcoholic steatohepatitis (NASH) is considered the progressive form of nonalcoholic fatty liver disease (NAFLD) and is characterized by liver steatosis, inflammation, hepatocellular injury and different degrees of fibrosis. A central issue in this field relates to the identification of those factors that trigger inflammation, thus fuelling the transition from nonalcoholic fatty liver to NASH. These triggers of liver inflammation might have their origins outside the liver (such as in adipose tissue or the gut) as well as inside the organ (for instance, lipotoxicity, innate immune responses, cell death pathways, mitochondrial dysfunction and endoplasmic reticulum stress), both of which contribute to NASH development. In this Review, we summarize the currently available information on the key upstream triggers of inflammation in NASH. We further delineate the mechanisms by which liver inflammation is resolved and the implications of a defective pro-resolution process. A better knowledge of these mechanisms should help to design targeted therapies able to halt or reverse disease progression.
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Affiliation(s)
- Susanne Schuster
- Department of Pediatrics, University of California, San Diego, CA, USA
| | - Daniel Cabrera
- Department of Gastroenterology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.,Departamento de Ciencias Químicas y Biológicas, Facultad de Salud, Universidad Bernardo O Higgins, Santiago, Chile
| | - Marco Arrese
- Department of Gastroenterology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.,Centre for Aging and Regeneration (CARE), Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Ariel E Feldstein
- Department of Pediatrics, University of California, San Diego, CA, USA.
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Eslam M, Valenti L, Romeo S. Genetics and epigenetics of NAFLD and NASH: Clinical impact. J Hepatol 2018; 68:268-279. [PMID: 29122391 DOI: 10.1016/j.jhep.2017.09.003] [Citation(s) in RCA: 606] [Impact Index Per Article: 101.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 09/01/2017] [Accepted: 09/04/2017] [Indexed: 02/07/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is now recognised as the most common liver disease worldwide. It encompasses a broad spectrum of conditions, from simple steatosis, through non-alcoholic steatohepatitis, to fibrosis and ultimately cirrhosis and hepatocellular carcinoma. A hallmark of NAFLD is the substantial inter-patient variation in disease progression. NAFLD is considered a complex disease trait such that interactions between the environment and a susceptible polygenic host background determine disease phenotype and influence progression. Recent years have witnessed multiple genome-wide association and large candidate gene studies, which have enriched our understanding of the genetic basis of NAFLD. Notably, the I148M PNPLA3 variant has been identified as the major common genetic determinant of NAFLD. Variants with moderate effect size in TM6SF2, MBOAT7 and GCKR have also been shown to have a significant contribution. The premise for this review is to discuss the status of research into important genetic and epigenetic modifiers of NAFLD progression. The potential to translate the accumulating wealth of genetic data into the design of novel therapeutics and the clinical implementation of diagnostic/prognostic biomarkers will be explored. Finally, personalised medicine and the opportunities for future research and challenges in the immediate post genetics era will be illustrated and discussed.
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Affiliation(s)
- Mohammed Eslam
- Storr Liver Centre, Westmead Institute for Medical Research, Westmead Hospital and University of Sydney, NSW, Australia.
| | - Luca Valenti
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy.
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, The Sahlgrenska Academy, University of Gothenburg, Sweden.
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The Potential Mechanisms of Berberine in the Treatment of Nonalcoholic Fatty Liver Disease. Molecules 2016; 21:molecules21101336. [PMID: 27754444 PMCID: PMC6273247 DOI: 10.3390/molecules21101336] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 09/26/2016] [Accepted: 09/29/2016] [Indexed: 01/04/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a globally observed metabolic disease with high prevalence both in adults and children. However, there is no efficient medication available yet. Increased evidence indicates that berberine (BBR), a natural plant product, has beneficial effects on NAFLD, though the mechanisms are not completely known. In this review, we briefly summarize the pathogenesis of NAFLD and factors that influence the progression of NAFLD, and focus on the potential mechanisms of BBR in the treatment of NAFLD. Increase of insulin sensitivity, regulation of adenosine monophosphate-activated protein kinase (AMPK) pathway, improvement of mitochondrial function, alleviation of oxidative stress, LDLR mRNA stabilization, and regulation of gut microenvironment are the major targets of BBR in the treatment of NAFLD. Additionally, reduction of proprotein convertase subtilisin/kexin 9 (PCSK9) expression and DNA methylation are also involved in pharmacological mechanisms of berberine in the treatment of NAFLD. The immunologic mechanism of BBR in the treatment of NAFLD, development of berberine derivative, drug combinations, delivery routes, and drug dose can be considered in the future research.
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Stevenson HL, Utay NS. Hepatic steatosis in HCV-infected persons in the direct-acting antiviral era. Trop Dis Travel Med Vaccines 2016; 2:21. [PMID: 28883965 PMCID: PMC5530934 DOI: 10.1186/s40794-016-0038-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Accepted: 09/22/2016] [Indexed: 02/07/2023] Open
Abstract
Hepatitis C virus (HCV) infects 130-170 million people worldwide. Recently, direct-acting antivirals have been shown to eradicate HCV infection in 90-95 % of non-cirrhotic patients depending on genotype, treatment experience, and regimen used. Similar rates are achieved among compensated cirrhotics, although longer treatment duration and/or ribavirin may be required. HCV uses host lipid metabolism for its lifecycle and can cause hepatic steatosis and insulin resistance. Hepatic steatosis, defined as excessive triglyceride deposition in hepatocytes, affects approximately half of HCV-infected individuals. Genetic factors and co-morbidities can drive further steatosis, which in turn can instigate fibrosis and progression to cirrhosis and hepatocellular carcinoma. Polymorphisms in genes that modulate lipid deposition in hepatocytes such as patatin-like phospholipase domain-containing protein 3 (PNPLA3) and transmembrane six superfamily member 2 (TM6SF2) predispose people to steatosis. Metabolic syndrome, obesity, and insulin resistance are increasing worldwide and further contribute to hepatic steatosis, and alcohol has long been recognized as a cause of lipid deposition in the liver. HIV and antiretroviral drugs, but not HBV, may further drive hepatic steatosis. While many of these factors limit response to interferon-based regimens for treating HCV, responses to direct-acting antivirals appear not to be impaired. The effect of HCV eradication on hepatic steatosis and progression to fibrosis, cirrhosis, and hepatocellular carcinoma warrants further study in the era of direct-acting antivirals.
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Affiliation(s)
- Heather L. Stevenson
- Department of Pathology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555 USA
| | - Netanya S. Utay
- Division of Infectious Diseases, Department of Medicine, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555 USA
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Dongiovanni P, Valenti L. Genetics of nonalcoholic fatty liver disease. Metabolism 2016; 65:1026-37. [PMID: 26409295 DOI: 10.1016/j.metabol.2015.08.018] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 08/23/2015] [Accepted: 08/26/2015] [Indexed: 02/07/2023]
Abstract
UNLABELLED Epidemiological, familial, and twin studies indicate that non-alcoholic fatty liver disease, now the leading cause of liver damage in developed countries, has a strong heritability. The common I148M variant of PNPLA3 impairing hepatocellular lipid droplets remodeling is the major genetic determinant of hepatic fat content. The I148M variant has a strong impact on the full spectrum of liver damage related to fatty liver, encompassing non-alcoholic steatohepatitis, advanced fibrosis, and hepatocellular carcinoma, and influences the response to therapeutic approaches. Common variants in GCKR enhance de novo hepatic lipogenesis in response to glucose and liver inflammation. Furthermore, the low-frequency E167K variant of TM6SF2 and rare mutations in APOB, which impair very low-density lipoproteins secretion, predispose to progressive fatty liver. CONCLUSIONS These and other recent findings reviewed here indicate that impaired lipid handling by hepatocytes has a major role in the pathogenesis of non-alcoholic fatty liver disease by triggering inflammation, fibrogenesis, and carcinogenesis. These discoveries have provided potential novel biomarkers for clinical use and have revealed intriguing therapeutic targets.
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Affiliation(s)
- Paola Dongiovanni
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico
| | - Luca Valenti
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico; Department of Pathophysiology and Transplantation, Università degli Studi Milano, Milan, Italy.
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31
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Lorbek G, Urlep Ž, Rozman D. Pharmacogenomic and personalized approaches to tackle nonalcoholic fatty liver disease. Pharmacogenomics 2016; 17:1273-1288. [PMID: 27377717 DOI: 10.2217/pgs-2016-0047] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a raising liver disease with increasing prevalence due to the epidemics of obesity and diabetes, with end points in cirrhosis or hepatocellular carcinoma. A multitude of genetic and metabolic perturbations, together with environmental factors, likely drive the disease. However, to date only a few genes, primarily PNPLA3 and TM6SF2, associate with NAFLD and there is no specific treatment. In this review we focus on the therapeutical aspects of NAFLD, taking into account drugs and lifestyle interventions. Sex also influences disease progression and treatment outcomes. Lastly, we discuss the present and potential future of personalized approaches to tackle NAFLD and how the known polymorphisms of NAFLD associated genes influence the choice and success of therapy.
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Affiliation(s)
- Gregor Lorbek
- Faculty of Medicine, Center for Functional Genomics & Bio-Chips, Institute of Biochemistry, University of Ljubljana, Ljubljana, Slovenia
| | - Žiga Urlep
- Faculty of Medicine, Center for Functional Genomics & Bio-Chips, Institute of Biochemistry, University of Ljubljana, Ljubljana, Slovenia
| | - Damjana Rozman
- Faculty of Medicine, Center for Functional Genomics & Bio-Chips, Institute of Biochemistry, University of Ljubljana, Ljubljana, Slovenia
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32
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Anstee QM, Seth D, Day CP. Genetic Factors That Affect Risk of Alcoholic and Nonalcoholic Fatty Liver Disease. Gastroenterology 2016; 150:1728-1744.e7. [PMID: 26873399 DOI: 10.1053/j.gastro.2016.01.037] [Citation(s) in RCA: 166] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 01/17/2016] [Accepted: 01/20/2016] [Indexed: 02/07/2023]
Abstract
Genome-wide association studies and candidate gene studies have informed our understanding of factors contributing to the well-recognized interindividual variation in the progression and outcomes of alcoholic liver disease and nonalcoholic fatty liver disease. We discuss the mounting evidence for shared modifiers and common pathophysiological processes that contribute to development of both diseases. We discuss the functions of proteins encoded by risk variants of genes including patatin-like phospholipase domain-containing 3 and transmembrane 6 superfamily member 2, as well as epigenetic factors that contribute to the pathogenesis of alcoholic liver disease and nonalcoholic fatty liver disease. We also discuss important areas of future genetic research and their potential to affect clinical management of patients.
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Affiliation(s)
- Quentin M Anstee
- Liver Research Group, Institute of Cellular Medicine, The Medical School, Newcastle University, Newcastle-upon-Tyne, United Kingdom.
| | - Devanshi Seth
- Centenary Institute of Cancer Medicine, Royal Prince Alfred Hospital, Camperdown, Australia; Drug Health Services, Royal Prince Alfred Hospital, Camperdown, Australia; Central Clinical School, The University of Sydney, Camperdown, Australia
| | - Christopher P Day
- Liver Research Group, Institute of Cellular Medicine, The Medical School, Newcastle University, Newcastle-upon-Tyne, United Kingdom
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33
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Macaluso FS, Maida M, Petta S. Genetic background in nonalcoholic fatty liver disease: A comprehensive review. World J Gastroenterol 2015; 21:11088-11111. [PMID: 26494964 PMCID: PMC4607907 DOI: 10.3748/wjg.v21.i39.11088] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 06/11/2015] [Accepted: 09/02/2015] [Indexed: 02/06/2023] Open
Abstract
In the Western world, nonalcoholic fatty liver disease (NAFLD) is considered as one of the most significant liver diseases of the twenty-first century. Its development is certainly driven by environmental factors, but it is also regulated by genetic background. The role of heritability has been widely demonstrated by several epidemiological, familial, and twin studies and case series, and likely reflects the wide inter-individual and inter-ethnic genetic variability in systemic metabolism and wound healing response processes. Consistent with this idea, genome-wide association studies have clearly identified Patatin-like phosholipase domain-containing 3 gene variant I148M as a major player in the development and progression of NAFLD. More recently, the transmembrane 6 superfamily member 2 E167K variant emerged as a relevant contributor in both NAFLD pathogenesis and cardiovascular outcomes. Furthermore, numerous case-control studies have been performed to elucidate the potential role of candidate genes in the pathogenesis and progression of fatty liver, although findings are sometimes contradictory. Accordingly, we performed a comprehensive literature search and review on the role of genetics in NAFLD. We emphasize the strengths and weaknesses of the available literature and outline the putative role of each genetic variant in influencing susceptibility and/or progression of the disease.
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Genetic Factors in the Pathogenesis of Nonalcoholic Fatty Liver and Steatohepatitis. BIOMED RESEARCH INTERNATIONAL 2015; 2015:460190. [PMID: 26273621 PMCID: PMC4530215 DOI: 10.1155/2015/460190] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 12/18/2014] [Indexed: 02/06/2023]
Abstract
Liver fat accumulation generally related to systemic insulin resistance characterizes nonalcoholic fatty liver disease (NAFLD), which in the presence of nonalcoholic steatohepatitis (NASH) can progress towards cirrhosis and hepatocellular carcinoma. Due to the epidemic of obesity, NAFLD is now the most frequent liver disease in Western countries. Epidemiological, familial, and twin studies provide evidence for a strong genetic component of NAFLD susceptibility. Recently, genome-wide association studies led to the identification of the major inherited determinants of hepatic fat accumulation: patatin-like phospholipase domain-containing 3 (PNPLA3) I148M gene and transmembrane 6 superfamily member 2 (TM6SF2) E167K gene variants, involved in lipid droplets remodelling and very low-density lipoproteins secretion, are the major determinants of interindividual differences in liver steatosis, and susceptibility to progressive NASH. In this review, we aimed to provide an overview of recent insights into the genetics of hepatic fat accumulation and steatohepatitis.
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