Lifestyle interventions for the treatment of non-alcoholic fatty liver disease in adults: a systematic review

4Ps medicine of the fatty liver: the research model of predictive, preventive, personalized and participatory medicine-recommendations for facing obesity, fatty liver and fibrosis epidemics

Relationship between adipose tissue and fatty liver, and its possible evolution in fibrosis, is supported by clinical and research experience. Given the multifactorial pathogenesis of non-alcoholic fatty liver disease (NAFLD), treatments for various contributory risk factors have been proposed; however, there is no single validated therapy or drug association recommended for all cases which can stand alone. Mechanisms, diagnostics, prevention and treatment of obesity, fatty liver and insulin resistance are displayed along with recommendations and position points. Evidences and practice can get sustainable and cost-benefit valuable outcomes by participatory interventions. These recommendations can be enhanced by comprehensive research projects, addressed to societal issues and innovation, market appeal and industry development, cultural acceptance and sustainability. The basis of participatory medicine is a greater widespread awareness of a condition which is both a disease and an easy documented and inclusive clue for associated diseases and unhealthy lifestyle. This model is suitable for addressing prevention and useful for monitoring improvement, worsening and adherence with non-invasive imaging tools which allow targeted approaches. The latter include health psychology and nutritional and physical exercise prescription expertise disseminated by continuous medical education but, more important, by concrete curricula for training undergraduate and postgraduate students. It is possible and recommended to do it by early formal teaching of ultrasound imaging procedures and of practical lifestyle intervention strategies, including approaches aimed to healthier fashion suggestions. Guidelines and requirements of research project funding calls should be addressed also to NAFLD and allied conditions and should encompass the goal of training by research and the inclusion of participatory medicine topics. A deeper awareness of ethics of competences in health professionals and the articulation of knowledge, expertise and skills of medical doctors, dieticians, health psychologists and sport and physical exercise graduates are the necessary strategy for detectin a suboptimal health status and achieving realistically beneficial lifestyle changes. “The devil has put a penalty on all things we enjoy in life. Either we suffer in health or we suffer in soul or we get fat” (Albert Einstein); the task of medical research and intervention is to make possible to enjoy life also without things that make sufferance in health and souls and which excessively increase body fat.

Review of nonalcoholic fatty liver disease in women with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in reproductive-aged women. Women with PCOS frequently have metabolic complications including insulin resistance (IR), early diabetes, hypertension and dyslipidemia. Recent studies have demonstrated an association between PCOS and another metabolic complication: nonalcoholic fatty liver disease (NAFLD). NAFLD occurs as a result of abnormal lipid handling by the liver, which sensitizes the liver to injury and inflammation. It can progress to nonalcoholic steatohepatitis (NASH), which is characterized by hepatocyte injury and apoptosis. With time and further inflammation, NASH can progress to cirrhosis. Thus, given the young age at which NAFLD may occur in PCOS, these women may be at significant risk for progressive hepatic injury over the course of their lives. Many potential links between PCOS and NAFLD have been proposed, most notably IR and hyperandrogenemia. Further studies are needed to clarify the association between PCOS and NAFLD. In the interim, clinicians should be aware of this connection and consider screening for NAFLD in PCOS patients who have other metabolic risk factors. The optimal method of screening is unknown. However, measuring alanine aminotransferase and/or obtaining ultrasound on high-risk patients can be considered. First line treatment consists of lifestyle interventions and weight loss, with possible pharmacologic interventions in some cases.

Non-alcoholic fatty liver disease: What has changed in the treatment since the beginning?

Non-alcoholic fatty liver disease (NAFLD) is an umbrella term to describe the entire spectrum of this common liver disease. In patients with NAFLD, especially those with non-alcoholic steatohepatitis (NASH), most often have one or more components of the metabolic syndrome, but this is not universal. Although most patients with NAFLD share many clinical features, only a subset of patients develops significant liver inflammation and progressive fibrosis. On the other hand, not all patients with NASH exhibit insulin resistance. NASH can be seen in patients who are lean and have no identifiable risk factors. Many clinical studies have tried numerous drugs and alternative medicine, however, investigators have failed to identify a safe and effective therapy for patients with NASH. As summarized, the heterogeneity of pathogenic pathways in individual patients with NASH may warrant the development of an individualized treatment according to the underlying pathogenic pathway. The differentiation of pathogenetic targets may require the development of diagnostic and prognostic biomarkers, and the identification of genetic susceptibilities. At present, evidence-based medicine provides only a few options including life-style modifications targeting weight loss, pioglitazone and vitamin E in non-diabetic patients with biopsy-proven NASH.

Nonalcoholic fatty liver disease and aging: Epidemiology to management

Nonalcoholic fatty liver disease (NAFLD) is common in the elderly, in whom it carries a more substantial burden of hepatic (nonalcoholic steatohepatitis, cirrhosis and hepatocellular carcinoma) and extra-hepatic manifestations and complications (cardiovascular disease, extrahepatic neoplasms) than in younger age groups. Therefore, proper identification and management of this condition is a major task for clinical geriatricians and geriatric hepatologists. In this paper, the epidemiology and pathophysiology of this condition are reviewed, and a full discussion of the link between NAFLD and the aspects that are peculiar to elderly individuals is provided; these aspects include frailty, multimorbidity, polypharmacy and dementia. The proper treatment strategy will have to consider the peculiarities of geriatric patients, so a multidisciplinary approach is mandatory. Non-pharmacological treatment (diet and physical exercise) has to be tailored individually considering the physical limitations of most elderly people and the need for an adequate caloric supply. Similarly, the choice of drug treatment must carefully balance the benefits and risks in terms of adverse events and pharmacological interactions in the common context of both multiple health conditions and polypharmacy. In conclusion, further epidemiological and pathophysiological insight is warranted. More accurate understanding of the molecular mechanisms of geriatric NAFLD will help in identifying the most appropriate diagnostic and therapeutic approach for individual elderly patients.

Mitochondrial dysfunction in obesity-associated nonalcoholic fatty liver disease: the protective effects of pomegranate with its active component punicalagin

AIMS

Punicalagin (PU) is one of the major ellagitannins found in the pomegranate (Punica granatum), which is a popular fruit with several health benefits. So far, no studies have evaluated the effects of PU on nonalcoholic fatty liver disease (NAFLD). Our work aims at studying the effect of PU-enriched pomegranate extract (PE) on high fat diet (HFD)-induced NAFLD.

RESULTS

PE administration at a dosage of 150 mg/kg/day significantly inhibited HFD-induced hyperlipidemia and hepatic lipid deposition. As major contributors to NAFLD, increased expression of pro-inflammatory cytokines such as tumor necrosis factor-alpha, interleukins 1, 4, and 6 as well as augmented oxidative stress in hepatocytes followed by nuclear factor (erythroid-derived-2)-like 2 (Nrf2) activation were normalized through PE supplementation. In addition, PE treatment reduced uncoupling protein 2 (UCP2) expression, restored ATP content, suppressed mitochondrial protein oxidation, and improved mitochondrial complex activity in the liver. In contrast, mitochondrial content was not affected despite increased peroxisomal proliferator-activated receptor-gamma coactivator-1α (PGC-1α) and elevated expression of genes related to mitochondrial beta-oxidation after PE treatment. Finally, PU was identified as the predominant active component of PE with regard to the lowering of triglyceride and cholesterol content in HepG2 cells, and both PU- and PE-protected cells from palmitate induced mitochondrial dysfunction and insulin resistance.

INNOVATION

Our work presents the beneficial effects of PE on obesity-associated NAFLD and multiple risk factors. PU was proposed to be the major active component.

CONCLUSIONS

By promoting mitochondrial function, eliminating oxidative stress and inflammation, PU may be a useful nutrient for the treatment of NAFLD.

Hepatic steatosis is highly prevalent in hepatitis B patients and negatively associated with virological factors

BACKGROUND AND AIMS

The interaction between hepatitis B virus (HBV) infection and hepatic steatosis remains unclear. We aimed to explore the trend of prevalence of hepatic steatosis and its relationship with virological factors in HBV infected patients.

METHODS

Consecutive untreated patients with chronic HBV infection at Shunde Hospital between 2002 and 2011 were included. Quantification of HBV replication markers was performed by enzyme immunoassay, real-time polymerase chain reaction assay and immunohistochemical staining. Hepatic steatosis was defined as at least 5% hepatocytes affected.

RESULTS

A total of 3,212 patients (2,574 men) with a mean age of 32 ± 9.3 years were analyzed. Serological testing showed detectable HBsAg in all, HBeAg in 63.8% and HBV DNA in 78.4% of patients. Liver biopsies demonstrated HBsAg- and HBcAg-positive immunostaining in 96.6 and 71% patients, respectively. Hepatic steatosis was present in 554 (17.3%) patients, with annual prevalence increased over time from 8.2 to 31.8% (trend analysis, x (2) = 51.657, P < 0.001). Compared to patients without steatosis, the percentages of serum HBeAg-positive and detectable HBV DNA, and intrahepatic HBsAg- and HBcAg-positive staining were decreased in steatosis patients (all P < 0.001). Adjusted for age and gender, intrahepatic HBsAg-positive staining remained as an independent factor associated with lower risk of steatosis (adjusted odds ratio 0.90, 95% confidence interval 0.835, 0.971) in multivariate analysis.

CONCLUSIONS

Hepatic steatosis in HBV infected patients has been raging over the past decade, and it is negatively associated with intrahepatic expression of HBsAg. Lifestyle intervention may be needed to halt the onset of steatosis in chronic HBV infection.

Non-alcoholic fatty liver disease: a practical approach to treatment

Non-alcoholic fatty liver disease (NAFLD) affects up to a third of the population in many developed countries. Between 10% and 30% of patients with NAFLD have non-alcoholic steatohepatitis (NASH) that can progress to cirrhosis. There are metabolic risk factors common to both NAFLD and cardiovascular disease, so patients with NASH have an increased risk of liver-related and cardiovascular death. Management of patients with NAFLD depends largely on the stage of disease, emphasising the importance of careful risk stratification. There are four main areas to focus on when thinking about management strategies in NAFLD: lifestyle modification, targeting the components of the metabolic syndrome, liver-directed pharmacotherapy for high risk patients and managing the complications of cirrhosis.

Glucagon-like peptide-1 analogue, liraglutide, improves liver fibrosis markers in obese women with polycystic ovary syndrome and nonalcoholic fatty liver disease

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) has been linked to polycystic ovary syndrome (PCOS) and carries an increased risk of liver cirrhosis. Procollagen type 3 amino-terminal peptide (PIIINP) is an independent predictor of liver cirrhosis.

OBJECTIVE

To assess whether 6-month treatment with GLP-1 analogue, liraglutide, improves markers of liver fibrosis.

DESIGN

A case-control study comparing women with PCOS to age- and weight-matched controls. PCOS was diagnosed according to the Rotterdam criteria. All participants underwent liver function tests and liver ultrasound scan to assess for fatty infiltration. Serum marker for liver fibrosis, PIIINP, was measured at baseline and after 6-month treatment with liraglutide 1·8 mg od.

RESULTS

Nineteen women with PCOS and 17 controls were recruited, age 32·8 ± 7·2 vs 33·5 ± 6·7 years and weight 100·9 ± 16·7 vs 99·3 ± 14·7 kg, respectively. At baseline, the PCOS group had higher testosterone 1·2 ± 0·3 vs 0·9 ± 0·3 nm (P = 0·01), HOMA-IR 5·1 ± 2·6 vs 3·5 ± 1·3 (P = 0·03), AST 22·4 ± 5·2 vs 18·8 ± 3·4 u/l (P = 0·04), PIIINP 4·4 ± 0·8 vs 3·5 ± 0·8 ug/ml (P = 0·01) and NAFLD seven (35%) vs none (P = 0·005), respectively. Twenty-five (69%) participants completed the study (13 PCOS, 12 controls). Following treatment, weight was reduced by 3·0 ± 4·2 kg (P = 0·01) and 3·8 ± 3·4 kg (P = 0·001), respectively. Similarly, HOMA-IR, hsCRP, triglycerides and urinary isoprostane significantly reduced in both groups. PIIINP significantly reduced the in PCOS group 4·4 ± 0·8 vs 3·7 ± 0·9 ug/ml (P < 0·01), but not in controls 3·5 ± 0·8 vs 3·2 ± 0·7 ug/ml (P = 0·08).

CONCLUSIONS

Treatment with liraglutide, and/or associated weight loss, significantly reduced PIIINP levels in obese women with PCOS. This may be an additional beneficial factor when considering the use of liraglutide in women with PCOS, obesity and NAFLD.

Progression of liver disease in non-alcoholic fatty liver disease: a prospective clinicopathological follow-up study

OBJECTIVE

To perform a follow-up study on non-alcoholic fatty liver disease (NAFLD) patients in our previous study using paired liver biopsy.

METHODS

Patients who were included in our previous study on NAFLD and agreed to receive a repeat liver biopsy were included in the study. Their clinical characteristics, laboratory examination results and histological analysis on the repeat liver biopsied specimens were prospectively collected and compared with those in the previous study.

RESULTS

Data from 35 patients (mean age 47.5 ± 10.9 years, male 40.0%) were analyzed. The mean interval between the liver biopsies was 6.4 ± 0.8 years. NAFLD activity score (NAS) worsened in 13, remained unchanged in 9 and ameliorated in 13. Fibrosis worsened in 18 and remained unchanged in 17. Two patients who were confirmed with cirrhosis at baseline developed decompensated cirrhosis. On multivariate analysis, elevated serum aspartate aminotransferase (AST) (odds ratio [OR] 10.74, 95% confidence interval [CI] 1.00-115.86, P = 0.050) and γ-glutamyl transpeptidase (γ-GT) (OR 16.10, 95% CI 1.30-198.90, P = 0.030) at follow-up were associated with worsened NAS. Patients with borderline NASH at baseline were more likely to have worsened NAS at follow-up than those with definite NASH (OR 12.67, 95% CI 2.29-70.02, P = 0.004). However, both groups had a similar likelihood of having worsened fibrosis at follow-up. No plausible factors were found to be associated with worsened fibrosis.

CONCLUSIONS

NAFLD patients with persistently elevated serum AST and γ-GT levels during follow-up should be suspected of having worsened NAS. NASH patients can have significant disease progression over a relatively short period of time and fibrosis might be irreversible without specific interventions.

Non-alcoholic fatty liver disease: what the clinician needs to know

Non-alcoholic fatty liver disease (NAFLD) is the most frequent cause of liver disease in the Western world. Furthermore, it is increasing worldwide, paralleling the obesity pandemic. Though highly frequent, only about one fifth of affected subjects are at risk of developing the progressive form of the disease, non-alcoholic steatohepatitis with fibrosis. Even in the latter, liver disease is slowly progressive, though, since it is so prevalent, it is already the third cause of liver transplantation in the United States, and it is predicted to get to the top of the ranking in few years. Of relevance, fatty liver is also associated with increased overall mortality and particularly increased cardiovascular mortality. The literature and amount of published papers on NAFLD is increasing as fast as its prevalence, which makes it difficult to keep updated in this topic. This review aims to summarize the latest knowledge on NAFLD, in order to help clinicians understanding its pathogenesis and advances on diagnosis and treatment.

Nonalcoholic fatty liver disease: A comprehensive review of a growing epidemic

Nonalcoholic fatty liver disease (NAFLD) is quickly becoming one of the most prominent causes of liver disease worldwide. The increasing incidence of NAFLD is tied to the obesity epidemic and the subsequent metabolic derangements brought along with it. Current efforts to elucidate the mechanism and causes of the disease have answered some questions, but much remains unknown about NAFLD. The aim of this article is to discuss the current knowledge regarding the pathogenesis of the disease, as well as the current and future diagnostic, preventative, and therapeutic options available to clinicians for the management of NAFLD.

Management of nonalcoholic fatty liver disease: an evidence-based clinical practice review

AIM

To build a consensus among Chilean specialists on the appropriate management of patients with nonalcoholic fatty liver disease (NAFLD) in clinical practice.

METHODS

NAFLD has now reached epidemic proportions worldwide. The optimal treatment for NAFLD has not been established due to a lack of evidence-based recommendations. An expert panel of members of the Chilean Gastroenterological Society and the Chilean Hepatology Association conducted a structured analysis of the current literature on NAFLD therapy. The quality of the evidence and the level of recommendations supporting each statement were assessed according to the recommendations of the United States Preventive Services Task Force. A modified three-round Delphi technique was used to reach a consensus among the experts.

RESULTS

A group of thirteen experts was established. The survey included 17 open-ended questions that were distributed among the experts, who assessed the articles associated with each question. The levels of agreement achieved by the panel were 93.8% in the first round and 100% in the second and third rounds. The final recommendations support the indication of lifestyle changes, including diet and exercise, for all patients with NAFLD. Proven pharmacological therapies include only vitamin E and pioglitazone, which can be used in nondiabetic patients with biopsy-proven nonalcoholic steatohepatitis (the progressive form of NAFLD), although the long-term safety and efficacy of these therapies have not yet been established.

CONCLUSION

Current NAFLD management is rapidly evolving, and new pathophysiology-based therapies are expected to be introduced in the near future. All NAFLD patients should be evaluated using a three-focused approach that considers the risks of liver disease, diabetes and cardiovascular events.

Pediatric non-alcoholic fatty liver disease: recent advances

Central obesity represents the major factor responsible for NAFLD, but several immunological and endocrinological mechanisms are involved in fatty infiltration in the liver, inflammation and fibrosis. Gut microbiota and genetic factors were recently indicated as major players in liver injury. Loss of weight and physical activity represent till now the cornerstone of treatment, but they are very difficult to obtain and to maintain. Several pharamocotherapeutic approaches including insulin sensitizers, omega-3 fatty acids and vitamin E have been extensively studied in randomized trials, but final conclusions still could not be formulated. Therefore, new treatments based on pathogenetic mechanisms leading to NAFLD are under evaluation to establish the effective pharmacological therapy of this disorder.

Non-alcoholic fatty liver disease in patients with diabetes mellitus

Non-alcoholic fatty liver disease (NAFLD), including the disease stages steatosis and non-alcoholic steatohepatitis, is the most common cause of chronic liver disease worldwide and linked to the epidemic of diabetes mellitus and obesity. It is characterized by a high cardiovascular and liver-related mortality and expected to be the leading cause for liver transplantation in the near future. This review summarizes recent progress made in our understanding of the disease pathogenesis and the clinical management of patients with NAFLD. Strategies to manage diabetes mellitus will be evaluated in terms of their effectiveness in treating patients with NAFLD and novel pharmacological targets capable to treat diabetes mellitus and NAFLD will be highlighted.

Epigenetic mechanisms underlying the link between non-alcoholic fatty liver diseases and nutrition

Non-alcoholic fatty liver disease (NAFLD) is defined as a pathologic accumulation of fat in the form of triglycerides (TG) in the liver (steatosis) that is not caused by alcohol. A subgroup of NAFLD patients shows liver cell injury and inflammation coupled with the excessive fat accumulation (steatohepatitis), which is referred to as non-alcoholic steatohepatitis (NASH). Patients with NASH may develop cirrhosis and hepatocellular carcinoma (HCC). NAFLD shares the key features of metabolic syndrome including obesity, hyperlipidemia, hypertension, and insulin resistance. The pathogenesis of NAFLD is multi-factorial, however the oxidative stress seems to plays a major role in the development and progression of the disease. The emerging field of epigenetics provides a new perspective on the pathogenesis of NAFLD. Epigenetics is an inheritable but reversible phenomenon that affects gene expression without altering the DNA sequence and refers to DNA methylation, histone modifications and microRNAs. Epigenetic manipulation through metabolic pathways such as one-carbon metabolism has been proposed as a promising approach to retard the progression of NAFLD. Investigating the epigenetic modifiers in NAFLD may also lead to the development of preventive or therapeutic strategies for NASH-associated complications.

Treatment of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is now the commonest cause of chronic liver disease in developed countries. Treatment depends on the stage of disease, and non-invasive methods for risk stratification are urgently needed. Lifestyle modification (aimed at weight loss and increasing physical activity) and management of the features of metabolic syndrome are vital for all patients with NAFLD. Metformin is the first-line therapy for diabetic patients with NAFLD and also reduces the risk of hepatocellular carcinoma. Clinicians should have a low threshold for introducing a statin for the management of dyslipidaemia. Antihypertensive agents that target the renin-angiotensin system should be first-line in NAFLD for the management of hypertension. For patients with progressive disease, liver-directed pharmacotherapy with vitamin E should be considered. Non-alcoholic steatohepatitis cirrhosis is an increasingly common indication for liver transplantation.

Management of fatty liver disease with the metabolic syndrome

Non-alcoholic fatty liver disease (NAFLD) is the liver disease of this century, increasing in parallel with obesity, insulin resistance and the metabolic syndrome. NAFLD can be seen as a component of the metabolic syndrome, and as such, contributing as a risk factor for cardiovascular disease. In fact, these patients die more often from cardiovascular disease than from direct consequences of liver disease. In this review, we will summarize the data that link NAFLD as a central player in this dysmetabolism, as well as the evidence for appropriate therapy, in order to improve not only liver disease prognosis, but also the overall prognosis and risk of mortality, with particular focus on cardiovascular risk.

Effect of oleic acid on the levels of eight metal ions in human hepatoma SMMC-7721 cells

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Its incidence is rising worldwide. However, no specific therapy has been shown to be effective in its treatment. In the present study, the in vitro NAFLD model was established in human SMMC-7721 cells by using oleic acid (OA). Then, content changes of eight cations, including sodium, magnesium, potassium, calcium, iron, copper, zinc, and manganese, were investigated in the experimental model. The results showed that OA induced a decrease in magnesium level, while an increase in iron one. Additionally, the supplementation of magnesium in the cell culture model was studied. It showed that magnesium ameliorated lipid accumulation induced by OA. Our results suggest that magnesium could decrease the risk of NAFLD and be used as a promising candidate for the treatment of NAFLD.

Liver enzymes and psychological well-being response to aerobic exercise training in patients with chronic hepatitis C

BACKGROUND

Chronic hepatitis C (CHC) is a medical condition that has broad implications for a person's physical and psychological health.

OBJECTIVE

The aim of this study was to detect changes in liver enzymes and psychological well-being in response to aerobic exercise training in patients with CHC.

MATERIAL AND METHODS

Fifty CHC patients were included in two equal groups. The first group (A) received aerobic exercise training in addition to their regular medical treatment. The second group (B) received no training and only has their regular medical treatment. The program consisted of three sessions per week for three months.

RESULTS

There was a significant decrease in mean values of Alkaline Phosphatase (ALP), Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), Gamma - Glutamyltransferase (GGT), Beck Depression Inventory (BDI ) & Profile of Mood States(POMS) and increase in Rosenberg Self-Esteem Scale (RSES) in group (A) after treatments, but the changes in group (B) were not significant. Also, there were significant differences between mean levels of the investigated parameters in group (A) and group (B) at the end of the study.

CONCLUSION

Aerobic exercise training improves hepatic enzymes and psychological well-being in patients with chronic hepatitis C.

Enhanced amelioration of high-fat diet-induced fatty liver by docosahexaenoic acid and lysine supplementations

Fatty liver disease is the most common pathological condition in the liver. Here, we generated high-fat diet-(HFD-) induced nonalcoholic fatty liver disease (NAFLD) in mice and tested the effects of docosahexaenoic acid (DHA) and lysine during a four-week regular chow (RC)feeding. Our results showed that 1% lysine and the combination of 1% lysine + 1% DHA reduced body weight. Moreover, serum triglyceride levels were reduced by 1% DHA and 1% lysine, whereas serum alanine transaminase activity was reduced by 1% DHA and 1% DHA + 0.5% lysine. Switching to RC reduced hepatic lipid droplet accumulation, which was further reduced by the addition of DHA or lysine. Furthermore, the mRNA expressions of hepatic proinflammatory cytokines were suppressed by DHA and combinations of DHA + lysine, whereas the mRNA for the lipogenic gene, acetyl-CoA carboxylase 1 (ACC1), was suppressed by DHA. In the gonadal adipose tissues, combinations of DHA and lysine inhibited mRNA expression of lipid metabolism-associated genes, including ACC1, fatty acid synthase, lipoprotein lipase, and perilipin. In conclusion, the present study demonstrated that, in conjunction with RC-induced benefits, supplementation with DHA or lysine further ameliorated the high-fat diet-induced NAFLD and provided an alternative strategy to treat, and potentially prevent, NAFLD.

Association of adiponectin with hepatic steatosis: a study of 1,349 subjects in a random population sample

Background

Objective of the present study was to examine the association between adiponectin and hepatic steatosis, and other biochemical and anthropometric parameters in healthy subjects.

Results

A total of 1349 subjects (age 18–65 years) underwent ultrasound examination of the liver. Mean adiponectin concentration for the study collective was 11.35 ± 6.28 μg/mL. The following parameters were assessed for their association with adiponectin: body-mass index (BMI); age; sex; arterial blood pressure; nicotine use; alcohol consumption; physical activity; metabolic syndrome; total, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol; triglycerides; aspartate aminotransferase (AST); alanine aminotransferase (ALT); γ-glutamyltransferase (GGT); alkaline phosphatase (AP); C-reactive protein (CRP); insulin sensitivity according to the Homeostasis Model Assessment (HOMA); random blood glucose; and the degree of steatosis of the liver. The numerical differences in the variables influencing adiponectin returned in the descriptive analysis were confirmed at bivariate analysis for BMI, ALT, AST, GGT, AP, total and HDL cholesterol, triglycerides, CRP, arterial blood pressure, metabolic syndrome, nicotine use and alcohol consumption. The logistic regression of the multivariate analysis showed that male sex, hepatic steatosis, BMI, metabolic syndrome, tobacco smoking and CRP correlate negatively with adiponectin, while age, moderate alcohol consumption and HDL cholesterol exhibit a positive association.

Conclusions

The results of the present study confirm the findings of previous research. Adiponectin correlates negatively with cardiometabolic risk factors and is an independent indicator for non-alcoholic fatty liver disease (NAFLD).

Immunological and molecular basis of nonalcoholic steatohepatitis and nonalcoholic fatty liver disease

The prevalence of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) is rising worldwide with the increasing incidence of obesity, Type 2 diabetes mellitus and metabolic syndrome. NASH is currently one of the most common indications of liver transplantation in the United States. The immune system plays a major role in the pathogenesis of NAFLD/NASH. The metabolic changes, associated with obesity and metabolic syndrome, induce immunological responses resulting in NAFLD and further aggravation of the metabolic derangement in a feed-forward loop. Genetic and endocrine factors modulate the immunological and metabolic responses and determine the pathophysiological features of NAFLD. Histologically, NAFLD is a spectrum that ranges from simple hepatic steatosis to severe steatohepatitis, liver cirrhosis and/or hepatocellular carcinoma. Liver cirrhosis and hepatocellular carcinoma are responsible for the morbidity and mortality of the disease. This article is a critical evaluation of our current knowledge of the immunological and molecular basis of the disease.

Clinical approaches to non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) ranges from simple steatosis to nonalcoholic steatohepatitis (NASH), leading to fibrosis and potentially cirrhosis, and it is one of the most common causes of liver disease worldwide. NAFLD is associated with other medical conditions such as metabolic syndrome, obesity, cardiovascular disease and diabetes. NASH can only be diagnosed through liver biopsy, but noninvasive techniques have been developed to identify patients who are most likely to have NASH or fibrosis, reducing the need for liver biopsy and risk to patients. Disease progression varies between individuals and is linked to a number of risk factors. Mechanisms involved in the pathogenesis are associated with diet and lifestyle, influx of free fatty acids to the liver from adipose tissue due to insulin resistance, hepatic oxidative stress, cytokines production, reduced very low-density lipoprotein secretion and intestinal microbiome. Weight loss through improved diet and increased physical activity has been the cornerstone therapy of NAFLD. Recent therapies such as pioglitazone and vitamin E have been shown to be beneficial. Omega 3 polyunsaturated fatty acids and statins may offer additional benefits. Bariatric surgery should be considered in morbidly obese patients. More research is needed to assess the impact of these treatments on a long-term basis. The objective of this article is to briefly review the diagnosis, management and treatment of this disease in order to aid clinicians in managing these patients.

Clinical approaches to non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) ranges from simple steatosis to nonalcoholic steatohepatitis (NASH), leading to fibrosis and potentially cirrhosis, and it is one of the most common causes of liver disease worldwide. NAFLD is associated with other medical conditions such as metabolic syndrome, obesity, cardiovascular disease and diabetes. NASH can only be diagnosed through liver biopsy, but noninvasive techniques have been developed to identify patients who are most likely to have NASH or fibrosis, reducing the need for liver biopsy and risk to patients. Disease progression varies between individuals and is linked to a number of risk factors. Mechanisms involved in the pathogenesis are associated with diet and lifestyle, influx of free fatty acids to the liver from adipose tissue due to insulin resistance, hepatic oxidative stress, cytokines production, reduced very low-density lipoprotein secretion and intestinal microbiome. Weight loss through improved diet and increased physical activity has been the cornerstone therapy of NAFLD. Recent therapies such as pioglitazone and vitamin E have been shown to be beneficial. Omega 3 polyunsaturated fatty acids and statins may offer additional benefits. Bariatric surgery should be considered in morbidly obese patients. More research is needed to assess the impact of these treatments on a long-term basis. The objective of this article is to briefly review the diagnosis, management and treatment of this disease in order to aid clinicians in managing these patients.

Risk of cardiovascular, cardiac and arrhythmic complications in patients with non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) has emerged as a public health problem of epidemic proportions worldwide. Accumulating clinical and epidemiological evidence indicates that NAFLD is not only associated with liver-related morbidity and mortality but also with an increased risk of coronary heart disease (CHD), abnormalities of cardiac function and structure (e.g., left ventricular dysfunction and hypertrophy, and heart failure), valvular heart disease (e.g., aortic valve sclerosis) and arrhythmias (e.g., atrial fibrillation). Experimental evidence suggests that NAFLD itself, especially in its more severe forms, exacerbates systemic/hepatic insulin resistance, causes atherogenic dyslipidemia, and releases a variety of pro-inflammatory, pro-coagulant and pro-fibrogenic mediators that may play important roles in the pathophysiology of cardiac and arrhythmic complications. Collectively, these findings suggest that patients with NAFLD may benefit from more intensive surveillance and early treatment interventions to decrease the risk for CHD and other cardiac/arrhythmic complications. The purpose of this clinical review is to summarize the rapidly expanding body of evidence that supports a strong association between NAFLD and cardiovascular, cardiac and arrhythmic complications, to briefly examine the putative biological mechanisms underlying this association, and to discuss some of the current treatment options that may influence both NAFLD and its related cardiac and arrhythmic complications.

Pathophysiology of NASH: perspectives for a targeted treatment

Non alcoholic steatohepatitis (NASH) is the more severe form of nonalcoholic fatty liver disease. In NASH, fatty liver, hepatic inflammation, hepatocyte injury and fibrogenesis are associated, and this condition may eventually lead to cirrhosis. Current treatment of NASH relies on the reduction of body weight and increase in physical activity, but there is no pharmacologic treatment approved as yet. Emerging data indicate that NASH progression results from parallel events originating from the liver as well as from the adipose tissue, the gut and the gastrointestinal tract. Thus, dysfunction of the adipose tissue through enhanced flow of free fatty acids and release of adipocytokines, and alterations in the gut microbiome generate proinflammatory signals that underlie NASH progression. Additional 'extrahepatic hits' include dietary factors and gastrointestinal hormones. Within the liver, hepatocyte apoptosis, ER stress and oxidative stress are key contributors to hepatocellular injury. In addition, lipotoxic mediators and danger signals activate Kupffer cells which initiate and perpetuate the inflammatory response by releasing inflammatory mediators that contribute to inflammatory cell recruitment and development of fibrosis. Inflammatory and fibrogenic mediators include chemokines, the cannabinoid system, the inflammasome and activation of pattern-recognition receptors. Here we review the major mechanisms leading to appearance and progression of NASH, focusing on both extrahepatic signals and local inflammatory mechanisms, in an effort to identify the most promising molecular targets for the treatment of this condition.

Pathophysiology of NASH: perspectives for a targeted treatment

Non alcoholic steatohepatitis (NASH) is the more severe form of nonalcoholic fatty liver disease. In NASH, fatty liver, hepatic inflammation, hepatocyte injury and fibrogenesis are associated, and this condition may eventually lead to cirrhosis. Current treatment of NASH relies on the reduction of body weight and increase in physical activity, but there is no pharmacologic treatment approved as yet. Emerging data indicate that NASH progression results from parallel events originating from the liver as well as from the adipose tissue, the gut and the gastrointestinal tract. Thus, dysfunction of the adipose tissue through enhanced flow of free fatty acids and release of adipocytokines, and alterations in the gut microbiome generate proinflammatory signals that underlie NASH progression. Additional 'extrahepatic hits' include dietary factors and gastrointestinal hormones. Within the liver, hepatocyte apoptosis, ER stress and oxidative stress are key contributors to hepatocellular injury. In addition, lipotoxic mediators and danger signals activate Kupffer cells which initiate and perpetuate the inflammatory response by releasing inflammatory mediators that contribute to inflammatory cell recruitment and development of fibrosis. Inflammatory and fibrogenic mediators include chemokines, the cannabinoid system, the inflammasome and activation of pattern-recognition receptors. Here we review the major mechanisms leading to appearance and progression of NASH, focusing on both extrahepatic signals and local inflammatory mechanisms, in an effort to identify the most promising molecular targets for the treatment of this condition.

Obesity-associated nonalcoholic fatty liver disease

Obesity is strongly associated with the prevalence of nonalcoholic fatty liver disease (NAFLD) in adult and pediatric populations. Nutrition, physical activity, and behavioral modifications are critical components of the treatment regimen for all obese patients with NAFLD. Bariatric surgeries that affect or restrict the flow of food through the gastrointestinal tract may improve liver histology in morbidly obese patients with nonalcoholic steatohepatitis (NASH), although randomized clinical trials and quasi-randomized clinical studies are lacking. Early detection of NASH and hepatic fibrosis using noninvasive biochemical and imaging markers that may replace liver biopsy is the current challenge.

Role of exercise in optimizing the functional status of patients with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is frequently concomitant with obesity. This article discusses factors that influence health and functional outcomes of people who develop NAFLD, including increased burden of illness, whole body function, performance, and perception of self-efficacy. Changes in macronutrients, amount of calories consumed, and decreased physical activity all negatively influence patient outcome. The benefits of exercise in this population are also discussed. To be effective, exercise must be performed, regularly and in conjunction with dietary and other behavioral change. Therefore, a lifelong commitment to exercise, activity, and diet are needed if NAFLD is to be successfully treated.

Tetramethylpyrazine reduces glucose and insulin-induced activation of hepatic stellate cells by inhibiting insulin receptor-mediated PI3K/AKT and ERK pathways

Hepatic stellate cell (HSC) activation is the central event during liver fibrogenesis. Metabolic syndrome characterized by hyperglycemia and hyperinsulinemia contributes to nonalcoholic steatohepatitis-associated liver fibrosis. This study was to investigate the effects of tetramethylpyrazine (TMP) on HSC activation induced by glucose and insulin (Glu/Ins) and the underlying mechanisms. Results showed that Glu/Ins significantly stimulated proliferation, invasion, adhesion, and extracellular matrix (ECM) production in HSCs. TMP inhibited HSC proliferation, invasion and adhesion, and reduced the expression of marker genes related to HSC activation in Glu/Ins-activated HSCs. Mechanistic evidence revealed that TMP reduced insulin receptor (InsR) expression and blocked the downstream phosphatidylinositol-3-kinase (PI3K)/AKT and extracellular signal-regulated kinase (ERK) cascades, which was required for TMP attenuation of HSC activation. Moreover, TMP modulated the genes relevant to ECM homeostasis favoring ECM degradation. It could be concluded that TMP inhibited Glu/Ins-stimulated HSC activation and ECM production by inhibiting InsR-mediated PI3K/AKT and ERK pathways.

Role of diet and nutritional management in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum ranging from simple steatosis to non-alcoholic steatohepatitis, which causes an increased risk of cirrhosis, type 2 diabetes, and cardiovascular complications. With the worldwide growing incidence of obesity, sedentary lifestyle, and unhealthy dietary pattern, NAFLD has currently been recognized as a major health burden. Dietary patterns and nutrients are the important contributors to the development, progression, and treatment of NAFLD and associated metabolic comorbidities. Generally, hypercaloric diet, especially rich in trans/saturated fat and cholesterol, and fructose-sweetened beverages seem to increase visceral adiposity and stimulate hepatic lipid accumulation and progression into non-alcoholic steatohepatitis, whereas reducing caloric intake, increasing soy protein and whey consumption, and supplement of monounsaturated fatty acids, omega-3 fatty acids, and probiotics have preventive and therapeutic effects. In addition, choline, fiber, coffee, green tea, and light alcohol drinking might be protective factors for NAFLD. Based on available data, at least 3-5% of weight loss, achieved by hypocaloric diet alone or in conjunction with exercise and behavioral modification, generally reduces hepatic steatosis, and up to 10% weight loss may be needed to improve hepatic necroinflammation. A sustained adherence to diet rather than the actual diet type is a major predictor of successful weight loss. Moreover, a healthy diet has benefits beyond weight reduction on NAFLD patients whether obese or of normal weight. Therefore, nutrition serves as a major route of prevention and treatment of NAFLD, and patients with NAFLD should have an individualized diet recommendation.

[The role of diet in non-alcoholic fatty liver disease]

Prevalence of non-alcoholic fatty liver disease (NAFLD) is about 20-25% in Korean adults population. Obesity is strongly associated with NAFLD and the prevention of obesity is a major public issue. Unfortunately, pharmacological treatment of obesity and NAFLD remains uncertain. Only weight loss by dietary changes been shown to lead to histological improvement in fatty liver. So the nutrition therapy is a cornerstone of treatment for NAFLD. Epidemiologic studies show that saturated fat, trans-fatty acid, carbohydrate, and simple sugar have strong correlation with intrahepatic fat accumulation. But, true associations with specific nutrients still remain unclear. Recently, fructose consumption has been rising in many countries and several epidemiologic studies show that fructose consumption has strong correlation with metabolic diseases. The consumption of excessively added sugar in the pathogenesis of steatohepatitis has received attention. Most clinicians agree with lifestyle modification are effective in histologic improvement. Total energy intake restriction is the most important action to reduce intrahepatic fat accumulation. Macronutrient composition may also have correlation with the development of NAFLD. To reduce the incidence of NAFLD, public statements on optimal dietary education program have been issused. Various specific dietary programs are suggested. Among them low fat diet and low carbohydrate diet are suggested in patients with NAFLD. However, there is no ideal diet to obtain the histological improvement in NAFLD. Further randomised controlled studies about specific diet are needed to determine the long-term benefit and histological improvement by ideal diet. Tailoring diet therapy to a patient's lifestyle is more important than universal specific dietary program.

No difference between high-fructose and high-glucose diets on liver triacylglycerol or biochemistry in healthy overweight men

BACKGROUND & AIMS

Diets high in fructose have been proposed to contribute to nonalcoholic fatty liver disease. We compared the effects of high-fructose and matched glucose intake on hepatic triacylglycerol (TAG) concentration and other liver parameters.

DESIGN

In a double-blind study, we randomly assigned 32 healthy but centrally overweight men to groups that received either a high-fructose or high-glucose diet (25% energy). These diets were provided during an initial isocaloric period of 2 weeks, followed by a 6-week washout period, and then again during a hypercaloric 2-week period. The primary outcome measure was hepatic level of TAG, with additional assessments of TAG levels in serum and soleus muscle, hepatic levels of adenosine triphosphate, and systemic and hepatic insulin resistance.

RESULTS

During the isocaloric period of the study, both groups had stable body weights and concentrations of TAG in liver, serum, and soleus muscle. The high-fructose diet produced an increase of 22 ± 52 μmol/L in the serum level of uric acid, whereas the high-glucose diet led to a reduction of 23 ± 25 μmol/L (P < .01). The high-fructose diet also produced an increase of 0.8 ± 0.9 in the homeostasis model assessment of insulin resistance, whereas the high-glucose diet produced an increase of only 0.1 ± 0.7 (P = .03). During the hypercaloric period, participants in the high-fructose and high-glucose groups had similar increases in weight (1.0 ± 1.4 vs 0.6 ± 1.0 kg; P = .29) and absolute concentration of TAG in liver (1.70% ± 2.6% vs 2.05% ± 2.9%; P = .73) and serum (0.36 ± 0.75 vs 0.33 ± 0.38 mmol/L; P = .91), and similar results in biochemical assays of liver function. Body weight changes were associated with changes in liver biochemistry and concentration of TAGs.

CONCLUSIONS

In the isocaloric period, overweight men who were on a high-fructose or a high-glucose diet did not develop any significant changes in hepatic concentration of TAGs or serum levels of liver enzymes. However, in the hypercaloric period, both high-fructose and high-glucose diets produced significant increases in these parameters without any significant difference between the 2 groups. This indicates an energy-mediated, rather than a specific macronutrient-mediated, effect. Clinical trials.gov no: NCT01050140.

Exercise as a therapeutic tool to prevent mitochondrial degeneration in nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease, encompassing hepatic steatosis, nonalcoholic steatohepatitis (NASH), fibrosis and cirrhosis, is a significant health problem associated with modern lifestyle, based on caloric overconsumption and physical inactivity. Although the mechanisms associated with progression from the 'benign' steatosis to NASH are still elusive, mitochondrial dysfunction seems to play an important role in this degenerative process. Degeneration of mitochondrial function during NASH has been associated with impaired β-oxidation, oxidative phosphorylation and increased reactive oxygen species production, contributing to hepatocyte death and inflammatory response. Despite the fact that several therapeutic approaches can be used in the context of NASH, including insulin-sensitizing agents, anti-obesity drugs, lipid-lowering drugs or mitochondrial-targeted drugs, dietary and physical activity are still the most effective strategies. In fact, active lifestyles decrease insulin resistance and body weight and result in decreased histological signs of liver injury. In fatty liver, physical activity prevents the disease progression through mitochondrial adaptations, namely by increasing cytochrome c content, enzyme activities and fatty acid oxidation, which are lost after some days of physical inactivity. However, less is known about the effect of physical activity on NASH-associated mitochondrial dysfunction. After a brief characterization of NASH and its association with liver mitochondrial (dys)function, the present review addresses the impact of physical (in)activity on NASH and, particularly, the possible contribution of active lifestyles to the modulation of liver mitochondrial dysfunction.

Piloting a multidisciplinary clinic for the management of non-alcoholic fatty liver disease: initial 5-year experience

OBJECTIVE

A multidisciplinary approach is advocated for the management of Non-Alcoholic Fatty Liver Disease (NAFLD), but few clinical data exist to support this. The objective of this study was to investigate the effectiveness of a multidisciplinary NAFLD clinic using surrogate markers of liver injury and cardiovascular risk.

DESIGN

Retrospective survey of clinical practice.

SETTING

The multidisciplinary NAFLD clinic in a secondary/tertiary care setting with hepatology, diabetology, dietetic and exercise therapy input: initial 5-years' experience (2007-2012).

PATIENTS

180 patients with NAFLD but without hepatic comorbidities were followed up for a median of 19.5 (range 3-57) months. 52% had type 2 diabetes mellitus, 48% were Europoid Caucasian, 17% were South Asian.

INTERVENTIONS

Multiple clinical interventions were employed including lifestyle (diet and exercise) advice, pharmacological intervention for cardiovascular risk factors, weight loss and exercise therapy.

MAIN OUTCOME MEASURES

Change in alanine aminotransferase (ALT), weight, HbA1c, lipid profile and blood pressure.

RESULTS

Median ALT fell from 61 (12-270) U/l to 50 (11-221) U/l, -18%, p<0.001, and weight fell from 90.5 (42.7-175.0) kg to 87.3 (45.9-175.3) kg, -3.5%, p<0.001. There were significant improvements in total cholesterol overall, triglycerides (among dyslipidaemic patients), HbA1c (among diabetic patients) and systolic blood pressure (among hypertensive patients). 24% of patients achieved ≥7% weight loss during follow-up and 17% maintained this weight loss throughout.

CONCLUSIONS

Improvement in liver biochemistry and cardiovascular risk factors was seen in patients attending the multidisciplinary NAFLD clinic. Refinement of this approach is warranted in light of these data, novel therapies and a growing evidence base.

Both resistance training and aerobic training reduce hepatic fat content in type 2 diabetic subjects with nonalcoholic fatty liver disease (the RAED2 Randomized Trial)

Although lifestyle interventions are considered the first-line therapy for nonalcoholic fatty liver disease (NAFLD), which is extremely common in people with type 2 diabetes, no intervention studies have compared the effects of aerobic (AER) or resistance (RES) training on hepatic fat content in type 2 diabetic subjects with NAFLD. In this randomized controlled trial, we compared the 4-month effects of either AER or RES training on insulin sensitivity (by hyperinsulinemic euglycemic clamp), body composition (by dual-energy X-ray absorptiometry), as well as hepatic fat content and visceral (VAT), superficial (SSAT), and deep (DSAT) subcutaneous abdominal adipose tissue (all quantified by an in-opposed-phase magnetic resonance imaging technique) in 31 sedentary adults with type 2 diabetes and NAFLD. After training, hepatic fat content was markedly reduced (P < 0.001), to a similar extent, in both the AER and the RES training groups (mean relative reduction from baseline [95% confidence interval] -32.8% [-58.20 to -7.52] versus -25.9% [-50.92 to -0.94], respectively). Additionally, hepatic steatosis (defined as hepatic fat content >5.56%) disappeared in about one-quarter of the patients in each intervention group (23.1% in the AER group and 23.5% in the RES group). Insulin sensitivity during euglycemic clamp was increased, whereas total body fat mass, VAT, SSAT, and hemoglobin A1c were reduced comparably in both intervention groups.

CONCLUSION

This is the first randomized controlled study to demonstrate that resistance training and aerobic training are equally effective in reducing hepatic fat content among type 2 diabetic patients with NAFLD.

The role of angiotensin II in nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is now considered the most prevalent chronic liver disease, affecting over 30% of the US adult population. NAFLD is strongly linked to insulin resistance and is considered the hepatic manifestation of the metabolic syndrome. Activation of the renin-angiotensin-aldosterone system (RAAS) is known to play a role in the hypertension observed in the metabolic syndrome and also is thought to play a central role in insulin resistance and NAFLD. Angiotensin II (AngII) is considered the primary effector of the physiological outcomes of RAAS signaling, both at the systemic and local tissue level. Herein, we review data describing the potential involvement of AngII-mediated signaling at multiple levels in the development and progression of NAFLD, including increased steatosis, inflammation, insulin resistance, and fibrosis. Additionally, we present recent work on the potential therapeutic benefits of RAAS and angiotensin II signaling inhibition in rodent models and patients with NAFLD.

Eating a healthy lunch improves serum alanine aminotransferase activity

Background

Nutritional guidance and diet control play important roles in the treatment of obesity and non-alcoholic fatty liver. However, in Japan, nutritional guidance is difficult to provide in practice. Therefore, we evaluated the effects of providing the ‘once-a-day’ intervention of a healthy lunch on various metabolic parameters.

Methods

For a 1-month preparatory period, 10 subjects generally consumed the lunches that were provided by the worksite cafeteria. This was followed by a 1-week washout period, after which, the subjects consumed healthy, low-calorie, well-balanced lunches for a 1-month test period. After the preparatory and test periods, blood samples were obtained from all subjects. The serum levels of indices relevant to metabolic syndrome and fatty liver were measured.

Results

Serum alanine aminotransferase activity significantly decreased by 20.3% after the healthy intervention. However, the indices of metabolic syndrome did not significantly change. Analysis of the relationship between serum alanine aminotransferase activity and nutrient content indicated that the improvement of serum alanine aminotransferase status was due to the higher vegetable content and lower animal-source protein of the meals provided.

Conclusions

In summary, the ‘once-a-day’ intervention of providing a healthy lunch improved serum alanine aminotransferase status. A diet high in vegetables and low in animal-based protein is important in maintaining a healthy condition.

[Alcoholic and non-alcoholic steatohepatitis: who is affected and what can we do for them?]

The most common causes of steatohepatitis are alcohol intake and metabolic disorders. Several methods based on biochemical determinations (carbohydrate deficient transferrin) and questionnaires (AUDIT, CAGE, MALE) are useful for detecting surreptitious alcohol intake. Although new non-invasive methods are under development, based both on lipidomics (Owl-Liver(®)) and on biochemical determinations and anthropometric parameters (NAFLD Fibrosis score) or imaging methods (DeMILI NASH-MRi(®)), none has been proposed as definitive and the gold standard continues to be liver biopsy. The pathogenesis of alcoholic and non-alcoholic steatohepatitis shares some elements such as insulin resistance, cytochrome CYP2E1-mediated oxidative stress, adiponutrin and its PNPLA3 gene, and the microbiota. The first-line treatment consists of lifestyle changes, including giving up alcohol, diet and exercise.

Short-term multidisciplinary non-pharmacological intervention is effective in reducing liver fat content assessed non-invasively in patients with nonalcoholic fatty liver disease (NAFLD)

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) ranges from simple steatosis to steatohepatitis, and cirrhosis in patients with alcohol intake less than 20 g/day, and is usually associated with insulin resistance (IR).

AIM

Given that no drugs are specifically approved for NAFLD, we tested the efficacy of a non-pharmacological multidisciplinary intervention based on a personalized diet, physical activity and behavior therapy.

METHODS

In this open non-randomized study, personalized diet, physical exercise and behaviour therapy for 3 months were prescribed in 12 consecutive patients with NAFLD. Lifestyle, including total caloric intake, physical activity and resting energy expenditure was monitored by a SenseWear Armband. Insulin Resistance (IR) was measured by HOMA and oral glucose insulin sensitivity tests (OGIS); fat liver content was estimated by two different semi-quantitative scores and by the Doppler Power Index (DPI).

RESULTS

Data show that the multidisciplinary intervention produced a significant reduction of total caloric intake, a 8% reduction in body weight, a modest increase in daily physical activity, a significant (P<0.001) reduction of aminotransferases and a decrease of total hepatic fat content.

CONCLUSIONS

A 3-month multidisciplinary intervention inducing at least 8% of weight loss, improves liver tests and decreases liver fat content.

A theoretical study of lipid accumulation in the liver-implications for nonalcoholic fatty liver disease

A hallmark of the nonalcoholic fatty liver disease is the accumulation of lipids. We developed a mathematical model of the hepatic lipid dynamics to simulate the fate of fatty acids in hepatocytes. Our model involves fatty acid uptake, lipid oxidation, and lipid export. It takes into account that storage of triacylglycerol within hepatocytes leads to cell enlargement reducing the sinusoids radius and impairing hepatic microcirculation. Thus oxygen supply is reduced, which impairs lipid oxidation. The analysis of our model revealed a bistable behavior (two stable steady states) of the system, in agreement with histological observations showing distinct areas of lipid accumulation in lobules. The first (healthy) state is characterized by intact lipid oxidation and a low amount of stored lipids. The second state in our model may correspond to the steatotic cell; it is marked by a high amount of stored lipids and a reduced lipid oxidation caused by impaired oxygen supply. Our model stresses the role of insufficient oxygen supply for the development of steatosis. We discuss implications of our results in regard to the experimental design aimed at exploring lipid metabolism reactions under steatotic conditions. Moreover, the model helps to understand the reversibility of lipid accumulation and predicts the reversible switch to show hysteresis. The system can switch from the steatotic state back to the healthy state by reduction of fatty acid uptake below the threshold at which steatosis started. The reversibility corresponds to the observation that caloric restriction can reduce the lipid content in the liver.

Alcoholic liver disease/nonalcoholic fatty liver disease index: distinguishing alcoholic from nonalcoholic fatty liver disease

OBJECTIVE

The alcoholic liver disease (ALD)/nonalcoholic fatty liver disease (NAFLD) (ANI) scoring system was constructed as a response to a clinical need for avoiding the risks of liver biopsy in diagnosing the etiology of fatty liver disease. The aim of this study was to test the reliability of ANI as a noninvasive method to distinguish ALD from NAFLD.

MATERIALS AND METHODS

One hundred and thirty-five patients were classified into two groups, ALD and NAFLD, according to the pathohistological results. Parameters for ANI are aspartate aminotransferase, alanine aminotransferase, mean corpuscular volume, BMI, and sex. ANI was calculated using an online calculator, official site of Mayo Clinic.

RESULTS

ANI was significantly higher in patients with ALD than NAFLD (P<0.01). The cutoff point of ANI is -0.66. ANI greater than -0.66 indicates ALD, whereas ANI less than -0.66 yields a higher probability of NAFLD with high specificity (96.7%) and sensitivity (84.1%). The mean corpuscular volume and aspartate aminotransferase/alanine aminotransferase ratio were higher, whereas BMI was lower in patients with ALD than in NAFLD (P<0.01).

CONCLUSION

The ANI scoring system may be used for the estimation of alcoholic origin of steatosis/steatohepatitis and may help in triaging patients for liver biopsy. ANI less than -0.66 indicates NAFLD, whereas ANI greater than -0.66 confirms the alcoholic etiology, but does not exclude the contribution of associated factors toward the development of fatty liver in a Serbian population.

Nonalcoholic fatty liver disease: current issues and novel treatment approaches

Nonalcoholic fatty liver disease (NAFLD) is considered the most common liver disorder in the Western world. It is commonly associated with insulin resistance, obesity, dyslipidaemia, type 2 diabetes mellitus (T2DM) and cardiovascular disease. Nonalcoholic steatohepatitis (NASH) is characterized by steatosis with necroinflammation and eventual fibrosis, which can lead to end-stage liver disease and hepatocellular carcinoma. Its pathogenesis is complex, and involves a state of 'lipotoxicity' in which insulin resistance, with increased free fatty acid release from adipose tissue to the liver, play a key role in the onset of a 'lipotoxic liver disease' and its progression to NASH. The diagnosis of NASH is challenging, as most affected patients are symptom free and the role of routine screening is not clearly established. A complete medical history is important to rule out other causes of fatty liver disease (alcohol abuse, medications, other). Plasma aminotransferase levels and liver ultrasound are helpful in the diagnosis of NAFLD/NASH, but a liver biopsy is often required for a definitive diagnosis. However, there is an active search for plasma biomarkers and imaging techniques that may non-invasively aid in the diagnosis. The treatment of NASH requires a multifaceted approach. The goal is to reverse obesity-associated lipotoxicity and insulin resistance via lifestyle intervention. Although there is no pharmacological agent approved for the treatment of NAFLD, vitamin E (in patients without T2DM) and the thiazolidinedione pioglitazone (in patients with and without T2DM) have shown the most consistent results in randomized controlled trials. This review concentrates on our current understanding of the disease, with a focus on the existing therapeutic approaches and potential future pharmacological developments for NAFLD and NASH.

Progression of NAFLD to diabetes mellitus, cardiovascular disease or cirrhosis

NAFLD is a spectrum of progressive liver disease that encompasses simple steatosis, NASH, fibrosis and, ultimately, cirrhosis. NAFLD is recognized as the hepatic component of the metabolic syndrome, as these conditions have insulin resistance as a common pathophysiological mechanism. Therefore, NAFLD is strongly associated with type 2 diabetes mellitus and abdominal obesity. As lifestyles have become increasingly sedentary and dietary patterns have changed, the worldwide prevalence of NAFLD has increased dramatically and is projected to be the principal aetiology for liver transplantation within the next decade. Importantly, a growing body of clinical and epidemiological evidence suggests that NAFLD is associated not only with liver-related morbidity and mortality, but also with an increased risk of developing both cardiovascular disease and type 2 diabetes mellitus. This article reviews the evidence that suggests NAFLD is a multisystem disease and the factors that might determine interindividual variation in the development and progression of its major hepatic and extrahepatic manifestations (principally type 2 diabetes mellitus and cardiovascular disease).

Omega-3 fatty acids for treatment of non-alcoholic fatty liver disease: design and rationale of randomized controlled trial

Background

Non-alcoholic fatty liver disease (NAFLD) is a liver manifestation of metabolic syndrome since obesity and insulin resistance are the main pathogenic contributors for both conditions. NAFLD carries increased risk of atherosclerosis and cardiovascular diseases. There is an urgent need to find effective and safe therapy for children and adults with NAFLD. Data from research and clinical studies suggest that omega-3 fatty acids may be beneficial in metabolic syndrome-related conditions and can reduce the risk of cardiovascular disease.

Methods/design

We are conducting a randomized, multicenter, double-blind, placebo-controlled trial of treatment with omega-3 fatty acids in children with NAFLD. Patients are randomized to receive either omega-3 fatty acids containing docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) or placebo for 24 weeks. The dose of omega-3 (DHA+ EPA) ranges from 450 to 1300 mg daily. Low calorie diet and increased physical activity are advised and monitored using validated questionnaires. The primary outcome of the trial is the number of patients who decreased ALT activity by ≥ 0,3 of upper limit of normal. The main secondary outcomes are improvement in the laboratory liver tests, liver steatosis on ultrasound, markers of insulin resistance and difference in fat/lean body mass composition after 6 months of intervention.

Discussion

Potential efficacy of omega-3 fatty acids in the treatment of NAFLD will provide needed rationale for use of this safe diet supplement together with weight reduction therapy in the growing population of children with NAFLD.

Trial registration

NCT01547910