Prevention and treatment of nonalcoholic fatty liver disease

Techniques and Algorithms for Hepatic Vessel Skeletonization in Medical Images: A Survey

Hepatic vessel skeletonization serves as an important means of hepatic vascular analysis and vessel segmentation. This paper presents a survey of techniques and algorithms for hepatic vessel skeletonization in medical images. We summarized the latest developments and classical approaches in this field. These methods are classified into five categories according to their methodological characteristics. The overview and brief assessment of each category are provided in the corresponding chapters, respectively. We provide a comprehensive summary among the cited publications, image modalities and datasets from various aspects, which hope to reveal the pros and cons of every method, summarize its achievements and discuss the challenges and future trends.

Liver Safety of Statins in Prediabetes or T2DM and Nonalcoholic Steatohepatitis: Post Hoc Analysis of a Randomized Trial

CONTEXT

Patients with nonalcoholic fatty liver disease have a high cardiovascular risk, but statins are rarely prescribed because of fear of hepatotoxicity.

OBJECTIVE

To prospectively assess the long-term safety of statins in patients with prediabetes/type 2 diabetes mellitus (T2DM) and nonalcoholic steatohepatitis (NASH).

DESIGN

Post hoc analysis of statin use during a randomized, controlled trial assessing pioglitazone vs placebo for NASH.

PATIENTS

A total of 101 patients (86 receiving statins) with biopsy-proven NASH and prediabetes/T2DM were followed for up to 36 months.

INTERVENTIONS

Oral glucose tolerance test and percutaneous liver biopsy (baseline, month 18, and month 36); liver magnetic resonance spectroscopy and euglycemic insulin clamp (baseline and month 18).

MAIN OUTCOME MEASURES

Histologic and biochemical safety of statin use among patients with NASH.

RESULTS

Only 37% of patients were receiving statins at enrollment despite their high cardiovascular risk. Statin nonusers had higher plasma alanine aminotransferase levels but similar histologic severity of liver disease at baseline. In both statin users and nonusers, the same number of patients (n = 4) had a twofold or greater increase in plasma aminotransferases during follow-up. One statin nonuser was discontinued from the study because of this elevation. Values returned to normal without any active measure in all other cases. No changes on liver histology or hepatic insulin resistance were observed in patients with NASH newly started on a statin and receiving placebo during the main study.

CONCLUSIONS

Statin therapy is safe in patients with prediabetes/T2DM and NASH. Given their high cardiovascular risk, statin therapy should be encouraged in this population.

Effect of modulation of PPAR-γ activity on Kupffer cells M1/M2 polarization in the development of non-alcoholic fatty liver disease

Abnormal lipid-mediated hepatic inflammatory-immune dysfunction and chronic low grade inflammation play an important role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Macrophage polarization is an important mechanism for the regulation of inflammatory response. Since PPAR-γ has emerged as a master regulator of macrophage polarization, we aimed to investigate the lipid-induced macrophage/Kupffer cell polarization in vivo and in vitro, and explore the association between PPAR-γ activity and macrophages M1/M2 polarization shifting. Here we showed that long-term high-fat diet increased Kupffer cells content with M1-predominant phenotype and increasing production of pro-inflammatory cytokines. Saturated fatty acids polarized Kupffer cells/macrophages to an M1-predominant phenotype while n-3 PUFA polarized Kupffer cells/macrophages to an M2 phenotype, which was associated with activation of NF-κB signal pathway and PPAR-γ respectively. Furthermore, up-regulation of PPAR-γ shifted lipid-induced macrophages polarization from M1-predominant phenotype to M2 phenotype. Macrophages polarization switch was associated with the interaction between PPAR-γ and NF-κBp65 signal pathway. Rosiglitazone restored high-fat diet-induced imblance of Kupffer cells M1/M2 polarization and alleviated hepatic steatosis as well as local pro-inflammatory response. These findings suggest that manipulation of PPAR-γ activity has the potential to balance lipid-induced M1/M2 macrophage/Kupffer cell polarization, and leading to prevent the development of NAFLD.

Non-alcoholic fatty liver disease is associated with early left ventricular dysfunction in childhood acute lymphoblastic leukaemia survivors

BACKGROUND

Childhood acute lymphoblastic leukaemia (ALL) survivors have an increased risk of metabolic and cardiovascular disease. We aimed to assess the presence of non-alcoholic fatty liver disease (NAFLD) in childhood ALL and if it is associated with early cardiovascular dysfunction.

METHODS

In total, 53 childhood ALL survivors and 34 controls underwent auxological evaluation, biochemical assay, liver, heart and vascular ultrasound study.

RESULTS

NAFLD was more frequent in ALL patients than in controls (39.6% vs 11.7%, P < 0.01). Patients with NAFLD were more obese and insulin resistant than patients without NAFLD. Flow-mediated dilatation and interventricular septum were lower in the ALL group than those in the control group (P < 0.001 for both). The patients with NAFLD showed lower left ventricular ejection fraction than those without NAFLD (P = 0.011). In ALL survivors, BMI-SDS and subcutaneous fat were the strongest predictors of NAFLD, whereas preperitoneal adipose tissue and C-reactive protein were the strongest predictors of left ventricular ejection fraction.

CONCLUSIONS

Childhood ALL survivors had higher prevalence of NAFLD than healthy controls, which is associated with early left ventricular impairment. In the case of fatty liver, a comprehensive heart evaluation is mandatory. We strongly recommend to prevent visceral adiposity in ALL survivors, to search for metabolic syndrome or its components and to reinforce the need of intervention on diet and lifestyle during the follow-up of these patients.

Resveratrol supplementation improves inflammatory biomarkers in patients with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the world. Resveratrol is a polyphenolic compound with antioxidant capacity that shows beneficial effects on down-regulation of inflammatory mediators and metabolic disorders. We hypothesized that supplementation with resveratrol can further improve the efficacy of lifestyle modifications in the management of NAFLD. In this randomized, double-blinded, controlled clinical trial, 50 NAFLD patients were supplemented with either a 500-mg resveratrol capsule or a placebo capsule for 12 weeks. Both groups were advised to follow an energy-balanced diet and received physical activity recommendations. Serum liver enzymes, inflammatory markers, hepatic steatosis and fibrosis, dietary intake, anthropometric measurements, and physical activity were assessed at both baseline and the end of the study. In both groups, anthropometric measurements (weight, body mass index, waist circumference), liver enzymes, and steatosis grade improved (P < 005). Resveratrol supplementation was associated with a significant reduction in liver enzyme alanine aminotransferase, inflammatory cytokines, nuclear factor κB activity, serum cytokeratin-18, and hepatic steatosis grade, as compared with placebo supplementation (P < .05). For the treatment of NAFLD, our results showed that 12 weeks of supplementation of 500 mg resveratrol, along with lifestyle modification, is superior to lifestyle modification alone. This is at least partially due to the attenuation of inflammatory markers and hepatocellular apoptosis. More studies are needed to confirm and increase the clinical application of the present results.

Advances in research of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) refers to a clinicopathologic syndrome characterized by a spectrum of histological abnormalities such as hepatocyte fatty degeneration and liver inflammation, not including those caused by alcohol and other specific factors. NAFLD is a heredity, environmental, metabolic disease, and its spectrum ranges from nonalcoholic fatty liver to nonalcoholic steatohepatitis and liver cirrhosis.

Histologically proven non-alcoholic fatty liver disease and clinically related factors in recipients after liver transplantation

Non-alcoholic fatty liver disease (NAFLD) affects a substantial proportion of the world population, and its prevalence has been increasing. The study was aimed at evaluating the prevalence and peri-transplant risk factors for post-liver transplantation (LT) NAFLD. A retrospective review was performed for adult recipients who underwent late protocol biopsy (>1 yr after LT) between August 2010 and December 2012. Hepatic steatosis was reviewed and graded by hepatopathologists, and the peri-transplant factors were analyzed for relationships to histologically proven NAFLD. Total 166 biopsies had been performed in 156 recipients. NAFLD was present in 27.1% at a mean period of 35.4 months between LT and biopsy, moderate and severe steatosis (≥33%) consisted of 28.9%. In multivariate analysis, pre-LT alcoholic cirrhosis (odds ratio [OR] 8.031, p = 0.003), obesity at biopsy (OR 3.873, p = 0.001), and preexisting donor graft steatosis (OR 3.147, p = 0.022) were significant risk factors for post-LT NAFLD. In conclusion, NAFLD represented a considerable portion of recipients, but this prevalence was not higher than those for general population. Three risk factors were significantly related to post-LT NAFLD, and recipients with those factors should be monitored for NAFLD. Furthermore, possible progression to non-alcoholic steatohepatitis (NASH) or fibrosis and metabolic syndrome should be considered in future studies.

Weight reduction improves markers of hepatic function and insulin resistance in type-2 diabetic patients with non-alcoholic fatty liver

OBJECTIVE

The incidence of non-alcoholic fatty liver disease (NAFLD) is increasing dramatically affecting up to 30% of the population worldwide. At present, treatment options are limited and pharmacological management of NAFLD has had disappointing results. Some of the best available evidence to improve NAFLD concerns lifestyle modification.

OBJECTIVE

To detect the degree of weight reduction needed to improve the markers of hepatic function and insulin resistance in type-2 diabetics with NAFLD.

METHODS

One hundred type-2 diabetic male patients with NAFLD were included into this study and divided into two equal groups. Group (A) received aerobic exercise training in addition to diet regimen. Group (B) received no treatment intervention.

RESULTS

There was a 26.99%, 40.8%, 33.81%, 32.73%, 37.8% and 15 % reduction in mean values of Alkaline Phosphatase (ALP), Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), Gamma - Glutamyltransferase (GGT) and Homeostasis Model Assessment-Insulin Resistance-index (HOMA-IR) and BMI respectively in group (A) at the end of the study. While there were significant differences between mean levels of the investigated parameters in group (A) and group (B) after treatment.

CONCLUSION

About 15 % reduction in BMI is effective to improve the liver condition and insulin resistance in type-2 diabetics with NAFLD.

Obesity and insulin resistance: an abridged molecular correlation

A relationship between obesity and type 2 diabetes is now generally well accepted. This relationship represents several major health hazards including morbid obesity and cardiovascular complications worldwide. Diabetes mellitus is a complex metabolic disorder characterized by impaired insulin release and insulin resistance. Lipids play an important physiological role in skeletal muscle, heart, liver and pancreas. Deregulation of fatty acid metabolism is the main culprit for developing insulin resistance and type 2 diabetes. A predominant predisposing factor to developing obesity, insulin resistance and type 2 diabetes is the permanent elevation of free fatty acids in plasma followed by impaired utilization of lipids by muscle. Diabetes-induced inflammation and oxidative stress have also vital role for development of insulin resistance in diabetic patients. The present review is intended to describe the correlation between lipids, obesity and insulin resistance based on current literature, in order to elucidate involved molecular mechanisms in depth.

Non-alcoholic fatty liver disease: a new and important cardiovascular risk factor?

Non-alcoholic fatty liver disease (NAFLD) affects up to a third of the population worldwide and may confer increased cardiometabolic risk with consequent adverse cardiovascular outcomes independent of traditional cardiovascular risk factors and the metabolic syndrome. It is characterized almost universally by insulin resistance and is strongly associated with type 2 diabetes and obesity. Non-alcoholic fatty liver disease is a marker of pathological ectopic fat accumulation combined with a low-grade chronic inflammatory state. This results in several deleterious pathophysiological processes including abnormal glucose, fatty acid and lipoprotein metabolism, increased oxidative stress, deranged adipokine profile, hypercoaguability, endothelial dysfunction, and accelerated progression of atherosclerosis. This ultimately leads to a dysfunctional cardiometabolic phenotype with cardiovascular mortality representing the main mode of premature death in NAFLD. This review is aimed at introducing NAFLD to the clinical cardiologist by discussing in-depth the evidence to date linking NAFLD with cardiovascular disease, reviewing the likely mechanisms underlying this association, as well as summarizing from a cardiologist's perspective, current and potential future treatment options for this increasingly prevalent disease.

Nonalcoholic fatty liver disease is associated with left ventricular diastolic dysfunction in patients with type 2 diabetes

OBJECTIVE

Data on cardiac function in patients with nonalcoholic fatty liver disease (NAFLD) are limited and conflicting. We assessed whether NAFLD is associated with abnormalities in cardiac function in patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

We studied 50 consecutive type 2 diabetic individuals without a history of ischemic heart disease, hepatic diseases, or excessive alcohol consumption, in whom NAFLD was diagnosed by ultrasonography. A tissue Doppler echocardiography with myocardial strain measurement was performed in all patients.

RESULTS

Thirty-two patients (64%) had NAFLD, and when compared with the other 18 patients, age, sex, BMI, waist circumference, hypertension, smoking, diabetes duration, microvascular complication status, and medication use were not significantly different. In addition, the left ventricular (LV) mass and volumes, ejection fraction, systemic vascular resistance, arterial elasticity, and compliance were also not different. NAFLD patients had lower e' (8.2 ± 1.5 vs. 9.9 ± 1.9 cm/s, P < 0.005) tissue velocity, higher E-to-e' ratio (7.90 ± 1.3 vs. 5.59 ± 1.1, P < 0.0001), a higher time constant of isovolumic relaxation (43.1 ± 10.1 vs. 33.2 ± 12.9 ms, P < 0.01), higher LV-end diastolic pressure (EDP) (16.5 ± 1.1 vs. 15.1 ± 1.0 mmHg, P < 0.0001), and higher LV EDP/end diastolic volume (0.20 ± 0.03 vs. 0.18 ± 0.02 mmHg, P < 0.05) than those without steatosis. Among the measurements of LV global longitudinal strain and strain rate, those with NAFLD also had higher E/global longitudinal diastolic strain rate during the early phase of diastole (E/SR(E)). All of these differences remained significant after adjustment for hypertension and other cardiometabolic risk factors.

CONCLUSIONS

Our data show that in patients with type 2 diabetes and NAFLD, even if the LV morphology and systolic function are preserved, early features of LV diastolic dysfunction may be detected.

Non-alcoholic fatty liver disease is independently associated with left ventricular hypertrophy in hypertensive Type 2 diabetic individuals

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) and left ventricular hypertrophy (LVH) are highly prevalent in Type 2 diabetes and both conditions are associated with an increased risk of incident cardiovascular disease. The aim of this study is to evaluate whether there is an association between NAFLD and echocardiographically detected LVH in Type 2 diabetes.

METHODS

We studied 116 consecutive patients with hypertension and Type 2 diabetes after excluding those with pre-existing history of cardiovascular disease, advanced kidney disease, excessive alcohol consumption and other known causes of chronic liver disease (e.g., virus, medications, autoimmunity, iron overload). NAFLD was diagnosed by means of ultrasonography, whereas LVH was diagnosed by means of conventional trans-thoracic echocardiography in all patients.

RESULTS

The prevalence of LVH was markedly higher among diabetic patients with NAFLD than among those without this disease (82% vs 18%; p=0.01). Multivariate logistic regression analysis revealed that NAFLD was associated with LVH independently of age, sex, body mass index, systolic blood pressure, glycated hemoglobin, duration of diabetes, and parameters of kidney function.

CONCLUSIONS

Our findings suggest that hypertensive Type 2 diabetic patients with NAFLD have a remarkably higher frequency of LVH than do hypertensive diabetic patients without steatosis, and that NAFLD is associated with LVH independently of classical cardiovascular risk factors and other potential confounders.

Mechanisms and implications of age-related changes in the liver: nonalcoholic Fatty liver disease in the elderly. Curr Gerontol Geriatr Res. 2011;2011:831536. [PMID: 21918648 PMCID: PMC3171768 DOI: 10.1155/2011/831536]

Nonalcoholic fatty liver disease (NAFLD) is hepatic steatosis associated with metabolic abnormalities such as overweight/central obesity, insulin resistance, type 2 diabetes (T2D), and dyslipidemia. NAFLD is becoming the most common liver disease in contemporary society, with the highest prevalence in those over 60 years. NAFLD pathology ranges from simple steatosis to a necroinflammatory fibrosing disorder called steatohepatitis (SH), the latter associated with high risk of developing cirrhosis, often occuring in the seventh to ninth decades of life. While the main health implications of NAFLD are increased risk of developing T2D, cardiovascular diseases, and common cancers, there is substantantially increased standardized mortality, and deaths from decompensated cirrhosis and hepatocellular carcinoma (HCC). Little is known about the interactive effects of ageing and NAFLD, with most studies focusing on the younger population. This paper summarises the epidemiology, pathogenesis, and clinical course of NAFLD, with particular attention to persons over age 60 years. An approach to the management of NASH and its complications in the elderly, will also be presented here.

Liver attenuation, pericardial adipose tissue, obesity, and insulin resistance: the Multi-Ethnic Study of Atherosclerosis (MESA)

Insulin resistance is linked to general and abdominal obesity, but its relation to hepatic lipid content and pericardial adipose tissue is less clear. The purpose of this study was to examine cross-sectional associations of liver attenuation, pericardial adipose tissue, BMI, and waist circumference with insulin resistance. We measured liver attenuation and pericardial adipose tissue using the existing cardiac computed tomography scans in 5,291 individuals free of clinical cardiovascular disease and diabetes in the Multi-Ethnic Study of Atherosclerosis (MESA) during the study's baseline visit (2000-2002). Low liver attenuation was defined as the lowest quartile and high pericardial adipose tissue as the upper quartile of volume (cm(3)). We used standard clinical definitions for obesity and abdominal obesity. Insulin resistance was assessed by the homeostasis model assessment of insulin resistance (HOMA(IR)) index. In multivariate linear regression with all adiposity measures in the model simultaneously, all adiposity measures were significantly (P < 0.0001) associated with insulin resistance: regression coefficients (±s.e.) were 0.31 (±0.02) for low liver attenuation, 0.27 (±0.02) for high pericardial adipose tissue, 0.27 (±0.02) for obesity, and 0.32 (±0.02) for abdominal obesity. We found significant differences (P = 0.003) between standardized liver attenuation and insulin resistance by ethnicity: regression coefficients per 1 s.d. increment were 0.10 ± 0.01 for whites, 0.11 ± 0.02 for Chinese, 0.08 ± 0.2 for blacks, and 0.14 ± 0.01 for Hispanics. Liver attenuation and pericardial adipose tissue were associated with insulin resistance, independent of BMI and waist circumference.

Risk of cardiovascular disease and chronic kidney disease in diabetic patients with non-alcoholic fatty liver disease: just a coincidence?

Non-alcoholic fatty liver disease (NAFLD) is estimated to afflict ~20-30% of the general population, and over 70% of the patients with Type 2 diabetes. Given the expected rise in the prevalence of obesity and diabetes, NAFLD will be, if not already there, an epidemic. The consequences of NAFLD are numerous, and range from progression to chronic liver disease with its associated morbidity and mortality, to worsening insulin resistance and Type 2 diabetes, to being a contributor to both cardiovascular disease (CVD) and chronic kidney disease (CKD). NAFLD is, therefore, a complex problem with implications far beyond the liver. This review focuses on the rapidly expanding body of clinical evidence suggesting that NAFLD is associated with an increased prevalence and incidence of both CVD and CKD in patients with diabetes. This association appears to be independent of obesity, hypertension, and other potential confounding factors. However, given the heterogeneity and small number of observational studies, further research is urgently required to corroborate the prognostic role of NAFLD in the development and progression of CVD and CKD among patients with diabetes, and to further elucidate the complex and intertwined mechanisms that link NAFLD with these adverse outcomes.

Non-alcoholic steatosis/steatohepatitis – 2010

A nem alkoholos eredetű zsírmáj és a steatohepatitis a kóros májműködés leggyakoribb oka. A szerzők áttekintik a kórkép fő kóroki tényezőit, kialakulásának lehetséges hátterét, klinikumát, valamint a kórisme felállításának nehézségeit. Nagy az igény olyan, nem invazív biomarkerek (TNF-α adiponektin, lipidperoxidáció termékei, citokeratin-18, hialuronsav), pontrendszerek (Fibrotest, APRI), vizsgálatok (Fibroscan) kidolgozására, amelyek a betegség előrehaladását, a gyulladást és a fibrosist jelzik. Mind ez idáig megfelelően hatékony kezelés nem ismert. A terápia részben a kiváltó tényezők eliminálását (testsúlycsökkentés), az anyagcserezavar (diabetes mellitus, hyperlipidaemia) kezelését célozza meg, részben a májvédelmet (antioxidánsok) helyezi előtérbe. Orv. Hetil., 2010, 47, 1940–1945.

Advances in the treatment of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the Western world, and its prevalence is predicted to rise in the future in parallel with rising levels of obesity and type 2 diabetes mellitus. It is commonly associated with insulin resistance. Many patients have coexisting obesity, hypertension, dyslipidaemia or hyperglycaemia, and are at increased risk of developing cardiovascular disease. Although patients with simple steatosis have a good prognosis, a significant percentage will develop nonalcoholic steatohepatitis which may progress to cirrhosis, end-stage liver failure and hepatocellular carcinoma. Despite promising results from several pilot studies and small to medium randomized controlled trials, there is currently no pharmacological agent that is licensed for the treatment of NAFLD. At present the mainstay of treatment for all patients is lifestyle modification using a combination of diet, exercise and behavioural therapy. With recent advances in the understanding of the pathogenesis of NAFLD, the goal of treatment has shifted from simply trying to clear fat from the liver and prevent progressive liver damage to addressing and treating the metabolic risk factors for the condition. To reduce liver-related and cardiovascular morbidity and mortality, all patients with NAFLD should be invited to enrol in adequately powered, randomized controlled studies testing novel therapies, many of which are targeted at reducing insulin resistance or preventing progressive liver disease. Coexisting obesity, hypertension, dyslipidaemia or hyperglycaemia should be treated aggressively. Orlistat, bariatric surgery, angiotensin receptor blockers, statins, fibrates, metformin and thiazolidinediones should all be considered, but treatments should be carefully tailored to meet the specific requirements of each patient. The efficacy and safety of any new treatment, as well as its cost-effectiveness, will need to be carefully evaluated before it can be advocated for widespread clinical use.