Non-alcoholic fatty liver disease (NAFLD) is a spectrum of liver disorders. It is defined by the presence of steatosis in more than 5% of hepatocytes with little or no alcohol consumption. Insulin ...resistance, the metabolic syndrome or type 2 diabetes and genetic variants of PNPLA3 or TM6SF2 seem to play a role in the pathogenesis of NAFLD. The pathological progression of NAFLD follows tentatively a "three-hit" process namely steatosis, lipotoxicity and inflammation. The presence of steatosis, oxidative stress and inflammatory mediators like TNF-α and IL-6 has been implicated in the alterations of nuclear factors such as CAR, PXR, PPAR-α in NAFLD. These factors may result in altered expression and activity of drug metabolizing enzymes (DMEs) or transporters.
Existing evidence suggests that the effect of NAFLD on CYP3A4, CYP2E1 and MRP3 is more consistent across rodent and human studies. CYP3A4 activity is down-regulated in NASH whereas the activity of CYP2E1 and the efflux transporter MRP3 is up-regulated. However, it is not clear how the majority of CYPs, UGTs, SULTs and transporters are influenced by NAFLD either in vivo or in vitro. The alterations associated with NAFLD could be a potential source of drug variability in patients and could have serious implications for the safety and efficacy of xenobiotics. In this review, we summarize the effects of NAFLD on the regulation, expression and activity of major DMEs and transporters. We also discuss the potential mechanisms underlying these alterations.
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Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Fatty liver associated with metabolic dysfunction is common, affects a quarter of the population, and has no approved drug therapy. Although pharmacotherapies are in development, response rates ...appear modest. The heterogeneous pathogenesis of metabolic fatty liver diseases and inaccuracies in terminology and definitions necessitate a reappraisal of nomenclature to inform clinical trial design and drug development. A group of experts sought to integrate current understanding of patient heterogeneity captured under the acronym nonalcoholic fatty liver disease (NAFLD) and provide suggestions on terminology that more accurately reflects pathogenesis and can help in patient stratification for management. Experts reached consensus that NAFLD does not reflect current knowledge, and metabolic (dysfunction) associated fatty liver disease “MAFLD” was suggested as a more appropriate overarching term. This opens the door for efforts from the research community to update the nomenclature and subphenotype the disease to accelerate the translational path to new treatments.
Non-alcoholic fatty liver disease(NAFLD)is the most common liver disease in the world.Presentation of the disease ranges from simple steatosis to non-alcoholic steatohepatitis(NASH).NAFLD is a ...hepatic manifestation of metabolic syndrome that includes central abdominal obesity along with other components.Up to80%of patients with NAFLD are obese,defined as a body mass index(BMI)>30 kg/m2.However,the distribution of fat tissue plays a greater role in insulin resistance than the BMI.The large amount of visceral adipose tissue(VAT)in morbidly obese(BMI>40 kg/m2)individuals contributes to a high prevalence of NAFLD.Free fatty acids derived from VAT tissue,as well as from dietary sources and de novo lipogenesis,are released to the portal venous system.Excess free fatty acids and chronic low-grade inflammation from VAT are considered to be two of the most important factors contributing to liver injury progression in NAFLD.In addition,secretion of adipokines from VAT as well as lipid accumulation in the liver further promotes inflammation through nuclear factor kappa B signaling pathways,which are also activated by free fatty acids,and contribute to insulin resistance.Most NAFLD patients are asymptomatic on clinical presentation,even though some may present with fatigue,dyspepsia,dull pain in the liver and hepatosplenomegaly.Treatment for NAFLD and NASH involves weight reduction through lifestyle modifications,anti-obesity medication and bariatric surgery.This article reviews the available information on the biochemical and metabolic phenotypes associated with obesity and fatty liver disease.The relative contribution of visceral and liver fat to insulin resistance is discussed,and recommendations for clinical evaluation of affected individuals is provided.
Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease, with a worldwide prevalence of 25%. In the United States, NAFLD and its subtype, nonalcoholic steatohepatitis, affect 30% ...and 5% of the population, respectively. Considering the ongoing obesity epidemic beginning in childhood, the rise in diabetes, and other factors, the prevalence of NAFLD along with the proportion of those with advanced liver disease is projected to continue to increase. This will have an important impact on public health reflected in health care costs, including impact on the need for liver transplantation, for which nonalcoholic steatohepatitis is already close to becoming the most common indication. NAFLD patients with evidence of nonalcoholic steatohepatitis and advanced fibrosis are at markedly increased risk of adverse outcomes, including overall mortality, and liver-specific morbidity and mortality, respectively. Identification of this cohort of NAFLD patients is paramount, given the associated poorer outcomes, in order to target resources to those who need it most. Various noninvasive tools have been developed in this regard. This review provides an update on the epidemiology, clinical and prognostic features, and diagnostic approach to patients with NAFLD.
Given the increasing prevalence of diabetes and obesity worldwide, the deleterious effects of non-alcoholic fatty liver disease (NAFLD) are becoming a growing challenge for public health. NAFLD is ...the most common chronic liver disease in the Western world. NAFLD is closely associated with metabolic disorders, including central obesity, dyslipidaemia, hypertension, hyperglycaemia and persistent abnormalities of liver function tests.In general NAFLD is a common denominer for a broad spectrum of damage to the liver, which can be due to hepatocyte injury, inflammatory processes and fibrosis. This is normally seen on liver biopsy and can range from milder forms (steatosis) to the more severe forms (non-alcoholic steatohepatitis (NASH), advanced fibrosis, cirrhosis and liver failure). In these patients, advanced fibrosis is the major predictor of morbidity and liver-related mortality, and an accurate diagnosis of NASH and NAFLD is mandatory. Histologic evaluation with liver biopsy remains the gold standard to diagnose NAFLD. Diagnosis of NAFLD is defined as presence of hepatic steatosis, ballooning and lobular inflammation with or without fibrosis. Weight loss, dietary modification, and the treatment of underlying metabolic syndrome remain the mainstays of therapy once the diagnosis is established. Dietary recommendations and lifestyle interventions, weight loss, and the treatment of underlying metabolic syndrome remain the mainstays of therapy once the diagnosis is established with promising results but are difficult to maintain. Pioglitazone and vitamin E are recommended by guidelines in selected patients. This review gives an overview of NAFLD and its treatment options.
Background and Aims
Cenicriviroc (CVC) is a C‐C chemokine receptors type 2 and 5 dual antagonist under evaluation for treating liver fibrosis in adults with nonalcoholic steatohepatitis (NASH). Year ...1 primary analysis of the 2‐year CENTAUR study showed that CVC had an antifibrotic effect without impacting steatohepatitis. Herein, we report the final data from year 2 exploratory analyses.
Approach and Results
This was a randomized, controlled study of adults with NASH, nonalcoholic fatty liver disease activity score ≥4, and NASH Clinical Research Network stage 1‐3 fibrosis. Participants in arms A and C received CVC 150 mg or placebo, respectively, for 2 years; arm B received placebo in year 1 and switched to CVC in year 2. Liver biopsy was performed at baseline, year 1, and year 2. Of 289 randomized participants, 242 entered year 2. At year 2, 24% of patients who switched to CVC and 17% who remained on placebo achieved ≥1‐stage fibrosis improvement and no worsening of NASH (P = 0.37). Twice the proportion on CVC who achieved fibrosis response at year 1 maintained benefit at year 2 (60% arm A versus 30% arm C), including 86% on CVC who had stage 3 fibrosis at baseline. Over 2 years, a similar proportion on CVC or placebo achieved ≥1‐stage fibrosis improvement and no worsening of NASH (15% arm A versus 17% arm C). In patients with fibrosis responses, we observed consistent reductions in levels of N‐terminal type 3 collagen propeptide and enhanced liver fibrosis scores, while increases in aspartate aminotransferase‐to‐platelet ratio index and Fibrosis‐4 scores were consistently observed in nonresponders. Safety profile was comparable across groups.
Conclusions
CVC was well tolerated, and year 2 data corroborate antifibrotic findings from year 1. The majority on CVC who achieved fibrosis response at year 1 maintained it at year 2, with greater effect in advanced fibrosis. ClinicalTrials.gov number, NCT02217475 (CENTAUR).
NAFLD is currently the main cause of chronic liver disease in developed countries, and the number of NAFLD patients is growing worldwide. NAFLD often has similar symptoms to other metabolic ...disorders, including type 2 diabetes and obesity. Recently, the role of the gut microbiota in the pathophysiology of many diseases has been revealed. Regarding NAFLD, experiments using gut microbiota transplants to germ-free animal models showed that fatty liver disease development is determined by gut bacteria. Moreover, the perturbation of the composition of the gut microbiota has been observed in patients suffering from NAFLD. Numerous mechanisms relating the gut microbiome to NAFLD have been proposed, including the dysbiosis-induced dysregulation of gut endothelial barrier function that allows for the translocation of bacterial components and leads to hepatic inflammation. In addition, the various metabolites produced by the gut microbiota may impact the liver and thus modulate NAFLD susceptibility. Therefore, the manipulation of the gut microbiome by probiotics, prebiotics or synbiotics was shown to improve liver phenotype in NAFLD patients as well as in rodent models. Hence, further knowledge about the interactions among dysbiosis, environmental factors, and diet and their impacts on the gut–liver axis can improve the treatment of this life-threatening liver disease and its related disorders.
The current epidemic of non-alcoholic fatty liver disease (NAFLD) is reshaping the field of hepatology all around the world. The widespread diffusion of metabolic risk factors such as obesity, ...type2-diabetes mellitus, and dyslipidemia has led to a worldwide diffusion of NAFLD. In parallel to the increased availability of effective anti-viral agents, NAFLD is rapidly becoming the most common cause of chronic liver disease in Western Countries, and a similar trend is expected in Eastern Countries in the next years. This epidemic and its consequences have prompted experts from all over the word in identifying effective strategies for the diagnosis, management, and treatment of NAFLD. Different scientific societies from Europe, America, and Asia-Pacific regions have proposed guidelines based on the most recent evidence about NAFLD. These guidelines are consistent with the key elements in the management of NAFLD, but still, show significant difference about some critical points. We reviewed the current literature in English language to identify the most recent scientific guidelines about NAFLD with the aim to find and critically analyse the main differences. We distinguished guidelines from 5 different scientific societies whose reputation is worldwide recognised and who are representative of the clinical practice in different geographical regions. Differences were noted in: the definition of NAFLD, the opportunity of NAFLD screening in high-risk patients, the non-invasive test proposed for the diagnosis of NAFLD and the identification of NAFLD patients with advanced fibrosis, in the follow-up protocols and, finally, in the treatment strategy (especially in the proposed pharmacological management). These difference have been discussed in the light of the possible evolution of the scenario of NAFLD in the next years.
We investigated non‐alcoholic fatty liver disease (NAFLD) prevalence and its metabolic associations in patients with type 1 diabetes (T1D), and in insulin‐naïve and insulin‐treated patients with type ...2 diabetes (T2D). Baseline data from patients who had liver fat content (LFC) evaluated by magnetic resonance imaging in four phase 3 studies of basal insulin peglispro (BIL) were analysed. Associations of NAFLD with clinical characteristics, glycaemic control and diabetes therapy were evaluated. The prevalence of NAFLD (defined as LFC ≥ 6%) was low in T1D (8.8%) but high in T2D, with greater prevalence in insulin‐naïve (75.6%) vs insulin‐treated (61.7%) T2D patients. LFC (mean ± SD) was higher in T2D patients (insulin‐naïve, 13.0% ± 8.4%; insulin‐treated, 10.2% ± 7.8%) than in T1D patients (3.2% ± 3.2%). In T2D, NAFLD was associated with several markers of insulin resistance. In all three populations, there was an absence of association of HbA1c with LFC, but insulin doses were higher in patients with NAFLD.
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