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Alarabi M, Pan Z, Romero-Gómez M, George J, Eslam M. Telomere length and mortality in lean MAFLD: the other face of metabolic adaptation. Hepatol Int 2024:10.1007/s12072-024-10701-6. [PMID: 38900410 DOI: 10.1007/s12072-024-10701-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 05/24/2024] [Indexed: 06/21/2024]
Abstract
BACKGROUND AND AIMS Healthy weight (lean) patients with metabolic dysfunction-associated fatty liver disease (MAFLD) have a more favorable metabolic and histological profile in cross-sectional studies compared with their non-lean counterparts. Paradoxically, they also have higher overall mortality. The underpinning pathophysiology of this paradox is not understood. Telomere attrition is associated with increased mortality in various diseases. METHODS We investigated the role of telomere length in the pathogenesis of lean MAFLD in cohorts with biopsy-proven MAFLD (n = 303). We measured serum malondialdehyde (MDA) levels and hepatic 8-hydroxydeoxyguanosine (8-OHdG) and 4-hydroxy-2-nonenal (4-HNE) expression (reactive oxygen species (ROS) markers), growth/differentiation factor-15 (GDF-15) and tested the effect of H2O2 on telomere length and activity in hepatocyte cell lines. The association between leukocyte telomere length and mortality was examined. RESULTS Telomere length was significantly lower in patients with lean MAFLD (p < 0.001). They also demonstrated an increase in ROS levels and decreases in GDF-15. H2O2 induced telomere shortening and reducing telomere activity in hepatocyte cell lines. We subsequently confirmed that telomere length shortening at baseline is associated with increased hazards of all-cause mortality; the deleterious effect was more profound in lean people. CONCLUSION Differences in telomere length in part explain the increased mortality of lean compared to non-lean patients with MAFLD. The effect is in part mediated through ROS activation and provide opportunities for therapy.
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Affiliation(s)
- Mohammad Alarabi
- Storr Liver Centre, Westmead Institute for Medical Research, Westmead Hospital and University of Sydney, Westmead, Sydney, 2145 NSW, Australia
| | - Ziyan Pan
- Storr Liver Centre, Westmead Institute for Medical Research, Westmead Hospital and University of Sydney, Westmead, Sydney, 2145 NSW, Australia
| | - Manuel Romero-Gómez
- Digestive Diseases Unit, Hospital Universitario Virgen del Rocío, Seville, Spain
| | - Jacob George
- Storr Liver Centre, Westmead Institute for Medical Research, Westmead Hospital and University of Sydney, Westmead, Sydney, 2145 NSW, Australia
| | - Mohammed Eslam
- Storr Liver Centre, Westmead Institute for Medical Research, Westmead Hospital and University of Sydney, Westmead, Sydney, 2145 NSW, Australia.
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Pan Z, Khatry MA, Yu ML, Choudhury A, Sebastiani G, Alqahtani SA, Eslam M. MAFLD: an ideal framework for understanding disease phenotype in individuals of normal weight. Ther Adv Endocrinol Metab 2024; 15:20420188241252543. [PMID: 38808010 PMCID: PMC11131400 DOI: 10.1177/20420188241252543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 04/10/2024] [Indexed: 05/30/2024] Open
Abstract
The prevalence of metabolic dysfunction-associated fatty liver disease (MAFLD) is significant, impacting almost one-third of the global population. MAFLD constitutes a primary cause of end-stage liver disease, liver cancer and the need for liver transplantation. Moreover, it has a strong association with increased mortality rates due to various extrahepatic complications, notably cardiometabolic diseases. While MAFLD is typically correlated with obesity, not all individuals with obesity develop the disease and a significant percentage of MAFLD occurs in patients without obesity, termed lean MAFLD. The clinical features, progression and underlying physiological mechanisms of patients with lean MAFLD remain inadequately characterized. The present review aims to provide a comprehensive summary of current knowledge on lean MAFLD and offer a perspective on defining MAFLD in individuals with normal weight. Key to this process is the concept of metabolic health and flexibility, which links states of dysmetabolism to the development of lean MAFLD. This perspective offers a more nuanced understanding of MAFLD and its underlying mechanisms and highlights the importance of considering the broader metabolic context in which the disease occurs. It also bridges the knowledge gap and offers insights that can inform clinical practice.
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Affiliation(s)
- Ziyan Pan
- Storr Liver Centre, Westmead Institute for Medical Research, Westmead Hospital and University of Sydney, Sydney, NSW, Australia
| | - Maryam Al Khatry
- Department of Gastroenterology, Obaidullah Hospital, Emirates Health Services, Ministry of Health, Ras Al Khaimah, United Arab Emirates
| | - Ming-Lung Yu
- School of Medicine and Doctoral Program of Clinical and Experimental Medicine, College of Medicine and Center of Excellence for Metabolic Associated Fatty Liver Disease, National Sun Yat-sen University, Kaohsiung, Taiwan
- Hepatobiliary Division, Department of Internal Medicine, Kaohsiung Medical University Hospital, College of Medicine and Center for Liquid Biopsy and Cohort Research, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Ashok Choudhury
- Department of Hepatology, Institute of Liver and Biliary Sciences, New Delhi, India
| | - Giada Sebastiani
- Division of Gastroenterology and Hepatology, McGill University Health Centre, Montreal, QC, Canada
| | - Saleh A. Alqahtani
- Organ Transplant Center of Excellence, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
- Division of Gastroenterology and Hepatology, Johns Hopkins University, Baltimore, MD, USA
| | - Mohammed Eslam
- Storr Liver Centre, Westmead Institute for Medical Research, Westmead Hospital and University of Sydney, 176 Hawkesbury Road, Westmead 2145, NSW, Australia
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Alghamdi W, Mosli M, Alqahtani SA. Gut microbiota in MAFLD: therapeutic and diagnostic implications. Ther Adv Endocrinol Metab 2024; 15:20420188241242937. [PMID: 38628492 PMCID: PMC11020731 DOI: 10.1177/20420188241242937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 02/22/2024] [Indexed: 04/19/2024] Open
Abstract
Metabolic dysfunction-associated fatty liver disease (MAFLD), formerly known as nonalcoholic fatty liver disease, is becoming a significant contributor to chronic liver disease globally, surpassing other etiologies, such as viral hepatitis. Prevention and early treatment strategies to curb its growing prevalence are urgently required. Recent evidence suggests that targeting the gut microbiota may help treat and alleviate disease progression in patients with MAFLD. This review aims to explore the complex relationship between MAFLD and the gut microbiota in relation to disease pathogenesis. Additionally, it delves into the therapeutic strategies targeting the gut microbiota, such as diet, exercise, antibiotics, probiotics, synbiotics, glucagon-like peptide-1 receptor agonists, and fecal microbiota transplantation, and discusses novel biomarkers, such as microbiota-derived testing and liquid biopsy, for their diagnostic and staging potential. Overall, the review emphasizes the urgent need for preventive and therapeutic strategies to address the devastating consequences of MAFLD at both individual and societal levels and recognizes that further exploration of the gut microbiota may open avenues for managing MAFLD effectively in the future.
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Affiliation(s)
- Waleed Alghamdi
- Division of Gastroenterology, Department of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mahmoud Mosli
- Division of Gastroenterology, Department of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Saleh A. Alqahtani
- Organ Transplant Center of Excellence, King Faisal Specialist Hospital & Research Center, Riyadh 11211, Saudi Arabia
- Division of Gastroenterology & Hepatology, Johns Hopkins University, Baltimore, MD, USA
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4
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Lu H. Inflammatory liver diseases and susceptibility to sepsis. Clin Sci (Lond) 2024; 138:435-487. [PMID: 38571396 DOI: 10.1042/cs20230522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 01/09/2024] [Accepted: 03/12/2024] [Indexed: 04/05/2024]
Abstract
Patients with inflammatory liver diseases, particularly alcohol-associated liver disease and metabolic dysfunction-associated fatty liver disease (MAFLD), have higher incidence of infections and mortality rate due to sepsis. The current focus in the development of drugs for MAFLD is the resolution of non-alcoholic steatohepatitis and prevention of progression to cirrhosis. In patients with cirrhosis or alcoholic hepatitis, sepsis is a major cause of death. As the metabolic center and a key immune tissue, liver is the guardian, modifier, and target of sepsis. Septic patients with liver dysfunction have the highest mortality rate compared with other organ dysfunctions. In addition to maintaining metabolic homeostasis, the liver produces and secretes hepatokines and acute phase proteins (APPs) essential in tissue protection, immunomodulation, and coagulation. Inflammatory liver diseases cause profound metabolic disorder and impairment of energy metabolism, liver regeneration, and production/secretion of APPs and hepatokines. Herein, the author reviews the roles of (1) disorders in the metabolism of glucose, fatty acids, ketone bodies, and amino acids as well as the clearance of ammonia and lactate in the pathogenesis of inflammatory liver diseases and sepsis; (2) cytokines/chemokines in inflammatory liver diseases and sepsis; (3) APPs and hepatokines in the protection against tissue injury and infections; and (4) major nuclear receptors/signaling pathways underlying the metabolic disorders and tissue injuries as well as the major drug targets for inflammatory liver diseases and sepsis. Approaches that focus on the liver dysfunction and regeneration will not only treat inflammatory liver diseases but also prevent the development of severe infections and sepsis.
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Affiliation(s)
- Hong Lu
- Department of Pharmacology, SUNY Upstate Medical University, Syracuse, NY 13210, U.S.A
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Fernandez CJ, Nagendra L, Pappachan JM. Metabolic Dysfunction-associated Fatty Liver Disease: An Urgent Call for Global Action. TOUCHREVIEWS IN ENDOCRINOLOGY 2024; 20:5-9. [PMID: 38812662 PMCID: PMC11132654 DOI: 10.17925/ee.2023.20.1.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 07/13/2023] [Indexed: 05/31/2024]
Abstract
There has been an exponential increase in the global prevalence of fatty liver disease in recent years in association with the obesity pandemic worldwide. 'Metabolic dysfunction-associated fatty liver disease', the new terminology adopted by an international panel of experts in 2020 to largely replace the old term 'non-alcoholic fatty liver disease', has now been accepted by most hepatologists and diabetologists across the globe. The term metabolic dysfunction-associated fatty liver disease was created to better reflect the metabolicand liver-specific manifestations and complications of fatty liver disease. It is important to disseminate our current understanding of this enigmatic disease among the global scientific fraternity. Recent publications, including articles from the latest issue of Endocrinology & Metabolism Clinics of North America, are attempting to fill this knowledge gap.
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Affiliation(s)
- Cornelius J Fernandez
- Department of Endocrinology & Metabolism, Pilgrim Hospital, United Lincolnshire Hospitals NHS Trust, Boston, UK
| | - Lakshmi Nagendra
- Department of Endocrinology, JSS Medical College, JSS Academy of Higher Education and Research, Mysore, India
| | - Joseph M Pappachan
- Department of Endocrinology & Metabolism, Lancashire Teaching Hospitals NHS Trust, Preston, UK
- Faculty of Science, Manchester Metropolitan University, Manchester, UK
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
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Sato-Espinoza K, Chotiprasidhi P, Huaman MR, Díaz-Ferrer J. Update in lean metabolic dysfunction-associated steatotic liver disease. World J Hepatol 2024; 16:452-464. [PMID: 38577539 PMCID: PMC10989317 DOI: 10.4254/wjh.v16.i3.452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 01/19/2024] [Accepted: 02/28/2024] [Indexed: 03/27/2024] Open
Abstract
BACKGROUND A new nomenclature consensus has emerged for liver diseases that were previously known as non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD). They are now defined as metabolic dysfunction-associated steatotic liver disease (MASLD), which includes cardiometabolic criteria in adults. This condition, extensively studied in obese or overweight patients, constitutes around 30% of the population, with a steady increase worldwide. Lean patients account for approximately 10%-15% of the MASLD population. However, the pathogenesis is complex and is not well understood. AIM To systematically review the literature on the diagnosis, pathogenesis, characteristics, and prognosis in lean MASLD patients and provide an interpretation of these new criteria. METHODS We conducted a comprehensive database search on PubMed and Google Scholar between January 2012 and September 2023, specifically focusing on lean NAFLD, MAFLD, or MASLD patients. We include original articles with patients aged 18 years or older, with a lean body mass index categorized according to the World Health Organization criteria, using a cutoff of 25 kg/m2 for the general population and 23 kg/m2 for the Asian population. RESULTS We include 85 studies in our analysis. Our findings revealed that, for lean NAFLD patients, the prevalence rate varied widely, ranging from 3.8% to 34.1%. The precise pathogenesis mechanism remained elusive, with associations found in genetic variants, epigenetic modifications, and adaptative metabolic response. Common risk factors included metabolic syndrome, hypertension, and type 2 diabetes mellitus, but their prevalence varied based on the comparison group involving lean patients. Regarding non-invasive tools, Fibrosis-4 index outperformed the NAFLD fibrosis score in lean patients. Lifestyle modifications aided in reducing hepatic steatosis and improving cardiometabolic profiles, with some medications showing efficacy to a lesser extent. However, lean NAFLD patients exhibited a worse prognosis compared to the obese or overweight counterpart. CONCLUSION MASLD is a complex disease comprising epigenetic, genetic, and metabolic factors in its pathogenesis. Results vary across populations, gender, and age. Limited data exists on clinical practice guidelines for lean patients. Future studies employing this new nomenclature can contribute to standardizing and generalizing results among lean patients with steatotic liver disease.
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Affiliation(s)
- Karina Sato-Espinoza
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55902, United States.
| | - Perapa Chotiprasidhi
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55902, United States
| | - Mariella R Huaman
- Obesity and Metabolic, Center for Obesity and Metabolic Health, Lima 02002, Lima, Peru
| | - Javier Díaz-Ferrer
- Hepatology Service, Department of Digestive Diseases, Hospital Nacional Edgardo Rebagliati Martins, Lima 02002, Lima, Peru
- Medicine Faculty, Universidad San Martin de Porres, Lima 02002, Lima, Peru
- Gastroenterology Service, Clinica Internacional, Lima 02002, Lima, Peru
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Souza M, Diaz I, Barchetta I, Mantovani A. Gastrointestinal cancers in lean individuals with non-alcoholic fatty liver disease: A systematic review and meta-analysis. Liver Int 2024; 44:6-14. [PMID: 37833849 DOI: 10.1111/liv.15763] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 09/16/2023] [Accepted: 10/03/2023] [Indexed: 10/15/2023]
Abstract
BACKGROUND & AIMS Obesity and non-alcoholic fatty liver disease (NAFLD) are known risk factors for gastrointestinal (GI) cancers. However, GI carcinogenesis in lean NAFLD patients remains unclear. This systematic review and meta-analysis aims to investigate the association between lean NAFLD and GI cancer risk. METHODS PubMed, Embase and Cochrane Library databases were systematically searched (from inception date to April 2023) for cohort studies assessing GI cancers in lean (body mass index [BMI] < 25 kg/m2 or < 23 kg/m2 in Asians) and non-lean (BMI ≥25 kg/m2 or ≥ 23 kg/m2 in Asians) NAFLD individuals. Data from eligible studies were extracted, and meta-analysis was carried out using a random effects model to obtain risk ratios (RRs) with 95% confidence intervals (CIs). Subgroup analyses, meta-regressions and sensitivity analyses were also performed. This study was registered in PROSPERO (CRD42023420902). RESULTS Eight studies with 56,745 NAFLD individuals (11% were lean) and 704 cases of incident GI cancers were included. Lean NAFLD was associated with higher risk of hepatic (RR 1.77, 95% CI 1.15-2.73), pancreatic (RR 1.97, 95% CI 1.01-3.86) and colorectal cancers (RR 1.53, 95% CI 1.12-2.09), compared to non-lean NAFLD. No significant differences were observed for oesophagus, gastric, biliary and small intestine cancers. CONCLUSIONS This study shows that lean NAFLD patients have an increased risk of liver, pancreatic and colorectal cancers compared to non-lean NAFLD patients, emphasizing the need to explore tailored cancer prevention strategies for this specific patient group. Further research is required to explore the mechanisms underlying the association between lean NAFLD and specific GI cancers.
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Affiliation(s)
- Matheus Souza
- Department of Internal Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ivanna Diaz
- Department of Internal Medicine, SUNY Downstate Health Sciences University, Brooklyn, New York, USA
| | - Ilaria Barchetta
- Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - Alessandro Mantovani
- Section of Endocrinology, Diabetes and Metabolism, University and Azienda Ospedaliera Universitaria Integrata of Verona, Verona, Italy
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Choi KY, Kim TY, Chon YE, Kim MN, Lee JH, Hwang SG, Lee J, Kwak MK, Hong E, Choi YM, Ha Y. Impact of anthropometric parameters on outcomes in Asians with metabolic dysfunction-associated fatty liver disease. J Cachexia Sarcopenia Muscle 2023; 14:2747-2756. [PMID: 37881112 PMCID: PMC10751424 DOI: 10.1002/jcsm.13351] [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: 01/28/2023] [Revised: 09/02/2023] [Accepted: 09/11/2023] [Indexed: 10/27/2023] Open
Abstract
BACKGROUND We examined the incidence and predictors of clinical outcomes in metabolic dysfunction-associated fatty liver disease (MAFLD), focusing on anthropometric parameters. METHODS Adult patients with MAFLD were identified in nationwide databases and a hospital cohort. Primary endpoints were atherosclerotic cardiovascular disease (ASCVD) and advanced fibrosis. Logistic and Cox regression analyses were used to analyse the association between anthropometric parameters and endpoints. RESULTS In total, 4407 of 15 256 (28.9%) and 6274 of 25 784 subjects (24.3%) had MAFLD in the nationwide database; of these, 403 (9.2%) and 437 (7.0%) subjects were of lean/normal weight, respectively. Compared to the overweight/obese group, the lean/normal weight group had a significantly lower muscle mass (15.0 vs. 18.9 kg) and handgrip strength (31.9 vs. 35.1 kg) and had a higher ASCVD risk (9.0% vs. 6.3% and 15.9% vs. 8.5%; Ps < 0.001). Sarcopenia (odds ratio [OR], 6.66; 95% confidence interval [CI], 1.79-24.80) and handgrip strength (OR, 0.92; 95% CI, 0.86-0.97; Ps = 0.005) were associated with the ASCVD risk in the lean/normal weight group. In a hospital cohort (n = 1363), the ASCVD risk was significantly higher in the lean/normal weight group than in the overweight/obese group (median follow-up, 39.1 months). Muscle mass was inversely correlated with the ASCVD risk (hazard ratio [HR], 0.72; 95% CI, 0.56-0.94), while visceral adiposity was associated with advanced fibrosis (HR, 1.36; 95% CI, 1.10-1.69; Ps < 0.05). CONCLUSIONS Muscle mass/strength was significantly associated with the ASCVD risk in patients with MAFLD. Visceral adiposity was an independent predictor of advanced fibrosis.
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Affiliation(s)
- Kyu Yeon Choi
- Department of Gastroenterology, CHA Bundang Medical CenterCHA UniversitySeongnamSouth Korea
| | - Tae Yeon Kim
- Department of Gastroenterology, CHA Bundang Medical CenterCHA UniversitySeongnamSouth Korea
| | - Young Eun Chon
- Department of Gastroenterology, CHA Bundang Medical CenterCHA UniversitySeongnamSouth Korea
| | - Mi Na Kim
- Department of Gastroenterology, CHA Bundang Medical CenterCHA UniversitySeongnamSouth Korea
| | - Joo Ho Lee
- Department of Gastroenterology, CHA Bundang Medical CenterCHA UniversitySeongnamSouth Korea
| | - Seong Gyu Hwang
- Department of Gastroenterology, CHA Gumi Medical CenterCHA UniversityGumiSouth Korea
| | - Jiwoo Lee
- Department of Endocrinology and Metabolism, Hallym University Dongtan Sacred Heart HospitalHallym University College of MedicineHwaseongSouth Korea
| | - Mi Kyung Kwak
- Department of Endocrinology and Metabolism, Hallym University Dongtan Sacred Heart HospitalHallym University College of MedicineHwaseongSouth Korea
| | - Eun‐Gyoung Hong
- Department of Endocrinology and Metabolism, Hallym University Dongtan Sacred Heart HospitalHallym University College of MedicineHwaseongSouth Korea
| | - Yun Mi Choi
- Department of Endocrinology and Metabolism, Hallym University Dongtan Sacred Heart HospitalHallym University College of MedicineHwaseongSouth Korea
| | - Yeonjung Ha
- Department of Gastroenterology, CHA Bundang Medical CenterCHA UniversitySeongnamSouth Korea
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Aggeletopoulou I, Kalafateli M, Tsounis EP, Triantos C. Epigenetic Regulation in Lean Nonalcoholic Fatty Liver Disease. Int J Mol Sci 2023; 24:12864. [PMID: 37629043 PMCID: PMC10454848 DOI: 10.3390/ijms241612864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 08/11/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD), the most prominent cause of chronic liver disease worldwide, is a rapidly growing epidemic. It consists of a wide range of liver diseases, from steatosis to nonalcoholic steatohepatitis, and predisposes patients to liver fibrosis, cirrhosis, and even hepatocellular carcinoma. NAFLD is strongly correlated with obesity; however, it has been extensively reported among lean/nonobese individuals in recent years. Although lean patients demonstrate a lower prevalence of diabetes mellitus, central obesity, dyslipidemia, hypertension, and metabolic syndrome, a percentage of these patients may develop steatohepatitis, advanced liver fibrosis, and cardiovascular disease, and have increased all-cause mortality. The pathophysiological mechanisms of lean NAFLD remain vague. Studies have reported that lean NAFLD demonstrates a close association with environmental factors, genetic predisposition, and epigenetic modifications. In this review, we aim to discuss and summarize the epigenetic mechanisms involved in lean NAFLD and to introduce the interaction between epigenetic patterns and genetic or non genetic factors. Several epigenetic mechanisms have been implicated in the regulation of lean NAFLD. These include DNA methylation, histone modifications, and noncoding-RNA-mediated gene regulation. Epigenetics is an area of special interest in the setting of lean NAFLD as it could provide new insights into the therapeutic options and noninvasive biomarkers that target this under-recognized and challenging disorder.
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Affiliation(s)
- Ioanna Aggeletopoulou
- Division of Gastroenterology, Department of Internal Medicine, University Hospital of Patras, 26504 Patras, Greece; (I.A.); (E.P.T.)
| | - Maria Kalafateli
- Department of Gastroenterology, General Hospital of Patras, 26332 Patras, Greece;
| | - Efthymios P. Tsounis
- Division of Gastroenterology, Department of Internal Medicine, University Hospital of Patras, 26504 Patras, Greece; (I.A.); (E.P.T.)
| | - Christos Triantos
- Division of Gastroenterology, Department of Internal Medicine, University Hospital of Patras, 26504 Patras, Greece; (I.A.); (E.P.T.)
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