Prospective histopathologic evaluation of lifestyle modification in nonalcoholic fatty liver disease: a randomized trial

Hidden in the Fat: Unpacking the Metabolic Tango Between Metabolic Dysfunction-Associated Steatotic Liver Disease and Metabolic Syndrome

Metabolic syndrome (MetS) and metabolic dysfunction-associated steatotic liver disease (MASLD) are closely related, with rapidly increasing prevalence globally, driving significant public health concerns. Both conditions share common pathophysiological mechanisms such as insulin resistance (IR), adipose tissue dysfunction, oxidative stress, and gut microbiota dysbiosis, which contribute to their co-occurrence and progression. While the clinical implications of this overlap, including increased cardiovascular, renal, and hepatic risk, are well recognized, current diagnostic and therapeutic approaches remain insufficient due to the clinical and individuals' heterogeneity and complexity of these diseases. This review aims to provide an in-depth exploration of the molecular mechanisms linking MetS and MASLD, identify critical gaps in our understanding, and highlight existing challenges in early detection and treatment. Despite advancements in biomarkers and therapeutic interventions, the need for a comprehensive, integrated approach remains. The review also discusses emerging therapies targeting specific pathways, the potential of precision medicine, and the growing role of artificial intelligence in enhancing research and clinical management. Future research is urgently needed to combine multi-omics data, precision medicine, and novel biomarkers to better understand the complex interactions between MetS and MASLD. Collaborative, multidisciplinary efforts are essential to develop more effective diagnostic tools and therapies to address these diseases on a global scale.

Deep phenotyping of patients with MASLD upon high-intensity interval training

Background & Aims

Exercise is a key component of lifestyle management in patients with metabolic dysfunction-associated steatotic liver disease (MASLD), but neither its therapeutic effect on the active stage of the disease, that is metabolic dysfunction-associated steatohepatitis (MASH) nor the mediating mechanisms have been characterized. Therefore, we performed multi-omic phenotyping of patients with MASLD-MASH on an exercise program.

Methods

Fifteen patients with MASLD conducted high-intensity interval training (HIIT) combined with home-based training for 12 weeks. MASLD was evaluated using histology, transient elastography, and multiparametric magnetic resonance imaging (MRI) before and after the intervention. Change in maximal oxygen consumption (VO2max) and MRI-determined liver fat were compared with a control group of patients with MASLD (n = 22). RNA sequencing was performed on liver, muscle, and fat biopsies of patients in the exercise group. Stool was analyzed by shotgun metagenomics and untargeted metabolomics was performed on plasma, urine, adipose, and stool.

Results

HIIT increased VO2max by 10.1% and improved mitochondrial metabolism in skeletal muscle, indicating improved cardiorespiratory fitness and adherence. VO2max increased significantly in the exercise group compared with controls. Histologically, no reduction in steatosis, MASH, or liver fibrosis was observed; however, transient elastography tended to improve. MRI-determined liver fat did not change in the exercise group compared with controls. HIIT induced changes in mRNA expression of genes related to beiging of adipose tissue and fibrogenesis in liver. In addition, specific gut microbial taxa and metabolites changed.

Conclusions

HIIT increased cardiorespiratory fitness and induced beneficial gene expression changes in muscle, adipose tissue, and liver, but without translation into histological improvement of MASLD. Longer exercise intervention trials are warranted to validate or refute current recommendations for exercise as a cornerstone treatment for MASLD-MASH.

Impact and implications

Despite exercise being considered as a key component of lifestyle management for steatotic liver disease, neither the clinical effects nor the mechanisms involved are completely understood. We show that a high-intensity interval training (HIIT) program in 15 patients with metabolic dysfunction-associated steatotic liver disease (MASLD) improved cardiorespiratory fitness, compared with 22 control patients with MASLD who did not participate in an exercise program, however, it did not improve MASLD. HIIT induced a positive effect on fat tissue and muscle metabolism which was accompanied with changes in certain gut bacteria and metabolites in blood and urine. These findings improve our understanding of the effects of exercise on the whole-body metabolism in relation to steatotic liver disease. As such, this study provides a basis for future exercise interventions in patients with MASLD, required to thoroughly test current guideline advice for exercise as a cornerstone treatment for MASLD of all stages.

Clinical trial registry

Dutch Trial Register (registration number NL7932).

Pediatric MASLD: current understanding and practical approach

Metabolic dysfunction-associated steatotic liver disease (MASLD) is now the most prevalent chronic liver disease in children in industrialized countries mainly due to the rise in obesity and overweight. Besides risk of progressive liver damage, MASLD also carries an increased risk of extra-hepatic morbidity, most importantly type 2 diabetes mellitus and cardiovascular disease. Important challenges remain in the prevention, detection, and treatment of this prevalent disorder. This review outlines the epidemiology and risk factors of MASLD and provides an approach to screening, diagnosis, and treatment based on current best available evidence and expert opinion. What is known: • NAFLD/MASLD is a common disorder in children strongly related to obesity/overweight and insulin resistance. • This silent disorder is underdiagnosed due to lack of awareness and lack of simple diagnostic criteria. What is new: • New diagnostic criteria have transformed NAFLD/MASLD from a diagnosis of exclusion to a positive diagnosis with simple criteria. • Effective treatments are emerging for adults and will likely become available for children. • Identifying children with NAFLD/MASLD has become even more important due to this new treatment perspective.

Histological improvements following energy restriction and exercise: The role of insulin resistance in resolution of MASH

BACKGROUND & AIMS

Metabolic dysfunction-associated steatohepatitis (MASH) is one of the most common liver diseases worldwide and is characterized by multi-tissue insulin resistance. The effects of a 10-month energy restriction and exercise intervention on liver histology, anthropometrics, plasma biochemistries, and insulin sensitivity were compared to standard of care (control) to understand mechanisms that support liver health improvements.

METHODS

Following medical diagnosis of MASH, individuals were randomized to treatment (n = 16) or control (n = 8). Liver fat (magnetic resonance spectroscopy), 18-hour plasma biochemical measurements, and isotopically labeled hyperinsulinemic-euglycemic clamps were completed pre- and post-intervention. Body composition and cardiorespiratory fitness (VO2peak) were also measured mid-intervention. Those in the treatment group were counseled to reduce energy intake and completed supervised, high-intensity interval training (3x/week) for 10 months. Controls continued physician-directed care.

RESULTS

Treatment induced significant (p <0.05) reductions in body weight, fat mass, and liver injury, while VO2peak (p <0.05) and non-esterified fatty acid suppression (p = 0.06) were improved. Both groups exhibited reductions in total energy intake, hemoglobin A1c, hepatic insulin resistance, and liver fat (p <0.05). Compared to control, treatment induced a two-fold increase in peripheral insulin sensitivity which was significantly related to higher VO2peak and resolution of liver disease.

CONCLUSIONS

Exercise and energy restriction elicited significant and clinically meaningful treatment effects on liver health, potentially driven by a redistribution of excess nutrients to skeletal muscle, thereby reducing hepatic nutrient toxicity. Clinical guidelines should emphasize the addition of aerobic exercise in lifestyle treatments for the greatest histologic benefit in individuals with advanced MASH.

IMPACT AND IMPLICATIONS

The mechanisms that underpin histologic improvement in individuals with metabolic dysfunction-associated steatohepatitis (MASH) are not well understood. This study evaluated the relationship between liver and metabolic health, testing how changes in one may affect the other. We investigated the effects of energy restriction and exercise on the association between multi-tissue insulin sensitivity and histologic improvements in participants with biopsy-proven MASH. For the first time, these results show that an improvement in peripheral (but not hepatic) insulin sensitivity and systemic markers of muscle function (i.e. cardiorespiratory fitness) were strongly related to resolution of liver disease. Extrahepatic disposal of substrates and improved fitness levels supported histologic improvement, confirming the addition of exercise as crucial to lifestyle interventions in MASH.

CLINICAL TRIAL NUMBER

NCT03151798.

NAFLD-associated hepatocellular carcinoma (HCC) - A compelling case for repositioning of existing mTORc1 inhibitors

The increasing prevalence of non-alcoholic fatty liver disease (NAFLD) is a growing concern for the high incidence rate of hepatocellular carcinoma (HCC) globally. The progression of NAFLD to HCC is heterogeneous and non-linear, involving intermediate stages of non-alcoholic steatohepatitis (NASH), liver fibrosis, and cirrhosis. There is a high unmet clinical need for appropriate diagnostic, prognostic, and therapeutic options to tackle this emerging epidemic. Unfortunately, at present, there is no validated marker to identify the risk of developing HCC in patients suffering from NAFLD or NASH. Additionally, the current treatment protocols for HCC don't differentiate between viral infection or NAFLD-specific etiology of the HCC and have a limited success rate. The mammalian target of rapamycin complex 1 (mTORc1) is an important protein involved in many vital cellular processes like lipid metabolism, glucose homeostasis, and inflammation. These cellular processes are highly implicated in NAFLD and its progression to severe liver manifestations. Additionally, hyperactivation of mTORc1 is known to promote cell proliferation, which can contribute to the genesis and progression of tumors. Many mTORc1 inhibitors are being evaluated for different types of cancers under various phases of clinical trials. This paper deliberates on the strong pathological implication of the mTORc1 signaling pathway in NAFLD and its progression to NASH and HCC and advocates for a systematic investigation of known mTORc1 inhibitors in suitable pre-clinical models of HCC having NAFLD/NASH-specific etiology.

Exploring Varied Treatment Strategies for Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

Metabolic dysfunction-associated steatotic liver disease (MASLD) represents a liver disorder characterized by steatosis with underlying metabolic risk factors. The prevalence of MASLD continues to rise, leading to increased patient risk of various complications. Recent research has been focused on new therapeutic strategies to reduce the incidence of MASLD and provide effective treatment plans to prevent further irreversible liver damage. The treatment approach is multifactorial, with a primary focus on weight loss and management of underlying comorbidities through lifestyle modifications, pharmacotherapy, or surgical options. Ongoing research is exploring new pharmacological therapies that could enhance the treatment of MASLD.

Effects of weight loss on metabolic dysfunction-associated fatty liver disease in Japanese people: Non-alcoholic fatty liver disease in the Gifu area, longitudinal analysis study

AIM

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a major health concern. This cohort study aimed to evaluate the association between weight loss and remission of MAFLD in the Japanese population to aid the development of efficient treatment strategies.

METHODS

This retrospective cohort study was conducted at a Japanese health screening center. Participants included 3309 individuals diagnosed with baseline MAFLD between 2004 and 2016. Logistic regression analysis was used to assess the association between MAFLD remission from baseline to 5 years and weight change.

RESULTS

After 5 years, 671 participants achieved MAFLD remission. Weight loss was associated with MAFLD remission for every 1 kg of weight loss over 5 years; the odds ratio for MAFLD remission was 1.24 (95% CI 1.15-1.34) for participants with type 2 diabetes, 1.40 (95% CI 1.35-1.45) for overweight participants, and 1.51 (95% CI 1.33-1.72) for non-overweight participants with metabolic dysfunctions. The cutoff values for weight loss for MAFLD remission were 1.9 kg for all participants, 3.0 kg for participants with type 2 diabetes, 1.9 kg for overweight participants, and 0.8 kg for non-overweight participants with metabolic dysfunctions.

CONCLUSIONS

Among participants diagnosed with MAFLD, weight loss was associated with MAFLD remission regardless of the type of metabolic dysfunction in MAFLD. The results of this study may contribute to the development of novel approaches to achieve MAFLD remission.

A scientifically validated combination of garcinol, curcuminoids, and piperine for mild to moderate nonalcoholic steatohepatitis patients-results from a randomized, double-blind, placebo-controlled study

Background

Garcinol is a naturally occurring compound from the fruit rind of the Garcinia indica, with antioxidant, anti-inflammatory, and anticancer properties. Curcuminoids are the active molecule from the rhizome of Curcuma longa, studied extensively for its health benefits as an anti-inflammatory and antioxidant activities. Non-alcoholic steatohepatitis (NASH) is the progressive form of nonalcoholic steatohepatitis characterized by liver fat and inflammation.

Objective

To evaluate the clinical efficacy and safety of Garcinol, Curcuminoids and piperine (GCP) combination in patients with mild to moderate NASH in a randomized, double-blind, placebo-controlled study.

Methods

The patients received one tablet (450 mg) of GCP containing garcinol-50 mg, curcuminoids -250 mg and piperine 5 mg or a placebo (450 mg of microcrystalline cellulose) twice daily for 90 days. Changes in circulating aspartate aminotransferase (AST), alanine transaminase (ALT) levels, liver stiffness measurement (LSM), and controlled attenuation parameter (CAP) using Fibroscan were compared from baseline to day 90. Anthropometric parameters, serum levels of lipids, Interleukin (IL-6), hsCRP, and adiponectin were estimated. Safety was evaluated by laboratory parameters and by monitoring adverse events.

Results

Seventy-two patients were randomized and 63 (GCP = 32, Placebo = 31) completed the study. The mean age of the patients was 48.3 ± 8.7 years (36 males and 27 females). The mean reduction in AST (U/L) was 9.53 in GCP and 3.16 in placebo (p < 0.001) and that of ALT (U/L) was 13.47 in GCP and 7.43 in Placebo (p = 0.002). The liver stiffness and CAP scores showed a better reduction in GCP (0.56 kPa and 12.38 db/m) compared to placebo (0.064 kPa and 10.42 db/m) p < 0.05. Consequently, the noninvasive Fibroscan-AST (FAST) score reduction was also found to be significant in GCP compared to placebo. Additionally, body weight, lipid levels, hsCRP, and IL-6 in serum decreased, while adiponectin levels increased in GCP-supplemented participants compared to placebo. The combination of garcinol and curcuminoids was well tolerated with no significant changes in hematological and clinical laboratory parameters during the 90-day supplementation.

Conclusion

Our results suggest that GCP could be a possible supplement for the management of NASH.Clinical trial registration: https://clinicaltrials.gov/, identifier CTRI/2019/11/022147.

Exercise in the Management of Metabolic-Associated Fatty Liver Disease (MAFLD) in Adults: A Position Statement from Exercise and Sport Science Australia

Metabolic-associated fatty liver disease (MAFLD) is the most prevalent chronic liver disease worldwide, affecting 25% of people globally and up to 80% of people with obesity. MAFLD is characterised by fat accumulation in the liver (hepatic steatosis) with varying degrees of inflammation and fibrosis. MAFLD is strongly linked with cardiometabolic disease and lifestyle-related cancers, in addition to heightened liver-related morbidity and mortality. This position statement examines evidence for exercise in the management of MAFLD and describes the role of the exercise professional in the context of the multi-disciplinary care team. The purpose of these guidelines is to equip the exercise professional with a broad understanding of the pathophysiological underpinnings of MAFLD, how it is diagnosed and managed in clinical practice, and to provide evidence- and consensus-based recommendations for exercise therapy in MAFLD management. The majority of research evidence indicates that 150-240 min per week of at least moderate-intensity aerobic exercise can reduce hepatic steatosis by ~ 2-4% (absolute reduction), but as little as 135 min/week has been shown to be effective. While emerging evidence shows that high-intensity interval training (HIIT) approaches may provide comparable benefit on hepatic steatosis, there does not appear to be an intensity-dependent benefit, as long as the recommended exercise volume is achieved. This dose of exercise is likely to also reduce central adiposity, increase cardiorespiratory fitness and improve cardiometabolic health, irrespective of weight loss. Resistance training should be considered in addition to, and not instead of, aerobic exercise targets. The information in this statement is relevant and appropriate for people living with the condition historically termed non-alcoholic fatty liver disease (NAFLD), regardless of terminology.

Time-restricted feeding combined with resistance exercise prevents obesity and improves lipid metabolism in the liver of mice fed a high-fat diet

Nonalcoholic fatty liver disease (NAFLD), a condition characterized by the accumulation of fat in the liver, is estimated to be the most common liver disease worldwide. Obesity is a major risk factor and contributor, and, accordingly, weight loss can improve NAFLD. Previous studies in preclinical models of diet-induced obesity and fatty liver disease have shown the independent benefits of resistance exercise training (RT) and time-restricted feeding (TRF) in preventing weight gain and hepatic build-up of fat. Here, we tested the combined effect of TRF and RT on obesity and NAFLD in mice fed a high-fat diet. Our results showed that both TRF-8-h food access in the active phase-and RT-consisting of three weekly sessions of ladder climbing-attenuated body weight gain, improved glycemic homeostasis, and decreased the accumulation of lipids in the liver. TRF combined with RT improved the respiratory exchange rate, energy expenditure, and mitochondrial respiration in the liver. Furthermore, gene expression analysis in the liver revealed lower mRNA expression of lipogenesis and inflammation genes along with increased mRNA of fatty acid oxidation genes in the TRF + RT group. Importantly, combined TRF + RT was shown to be more efficient in preventing obesity and metabolic disorders. In conclusion, TRF and RT exert complementary actions compared with isolated interventions, with significant effects on metabolic disorders and NAFLD in mice.NEW & NOTEWORTHY Whether time-restricted feeding (TRF) combined with resistance exercise training (RT) may be more efficient compared with these interventions alone is still unclear. We show that when combined with RT, TRF provided additional benefits, being more effective in increasing energy expenditure, preventing weight gain, and regulating glycemic homeostasis than each intervention alone. Thus, our results demonstrate that TRF and RT have complementary actions on some synergistic pathways that prevented obesity and hepatic liver accumulation.

Fatty Liver Education Promotes Physical Activity in Vulnerable Groups, Including Those With Unhealthy Alcohol Use

BACKGROUND AND AIMS

Fatty liver disease (FLD), alcohol-associated and metabolically associated, often coexists. Increase in physical activity is associated with metabolic health and decreased FLD. We aimed to identify factors associated with physical activity and its improvement following FLD education in a racially diverse, vulnerable population.

METHODS

From February 19, 2020 to December 30, 2022, 314 adults with FLD at safety-net hepatology clinics in San Francisco were surveyed at baseline, immediately after FLD education, and at 6-month follow-up. After collecting clinical and sociodemographic data, logistic regression (adjusted for age, sex, and race/ethnicity) assessed factors associated with physical activity at baseline and its improvement following education.

RESULTS

Participant characteristics in those without vs with any physical activity were median age 49 vs 55 years, 64% vs 56% female, 66% vs 53% Hispanic race/ethnicity, 75% vs 55% obese, and 30% vs 22% consumed heavy alcohol, respectively. On multivariable analysis, older age was the only significant factor associated with physical activity at baseline (relative risk ratio 1.37 per decade increase, 95% confidence interval [CI] 1.07-1.75). Hispanic (vs non-Hispanic) participants had a significantly higher odds of improvement in physical activity (vs no change) 6 months after education (odds ratio 2.36, 95% CI 1.27-4.39). Among those with suboptimal or no physical activity at baseline, participants who consumed heavy alcohol (vs no drinking) had a significantly higher likelihood of achieving optimal physical activity following education (relative risk ratio 1.98, 95% CI 1.05-3.74).

CONCLUSION

Despite social and structural barriers, FLD education increased uptake of physical activity in vulnerable populations, especially among Hispanic individuals and those consuming heavy alcohol. Implementation of patient-centered education is important for FLD management.

Exercise Does Not Independently Improve Histological Outcomes in Biopsy-Proven Non-Alcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis

INTRODUCTION

The independent effect of exercise on liver histology in non-alcoholic fatty liver disease (NAFLD) remains unclear. As such, we conducted a systematic review and meta-analysis of the effect of exercise alone on histological endpoints in biopsy-proven NAFLD.

MATERIALS AND METHODS

A systematic literature search was conducted to include controlled clinical trials investigating the effect of exercise alone on liver histology in biopsy-proven NAFLD. Meta-analysis was conducted for histological outcomes with available data from a minimum of three studies. Pooled estimates of the effect of exercise on histological endpoints were calculated using random-effects models.

RESULTS

We identified three controlled clinical trials that assessed the independent effect of exercise on histological outcomes in patients with biopsy-proven NAFLD. The studies consisted of 72 total participants, including 40 subjects in the exercise intervention and 32 individuals in the comparison group. Meta-analysis showed that exercise did not significantly improve Brunt grade, NAFLD activity score, and fibrosis in NAFLD.

DISCUSSION

Exercise alone may not lead to significant histopathological improvement in NAFLD. Future well-powered randomized controlled trials are needed to better characterize the impact of exercise on histological outcomes and clinical endpoints.

Dietary strategies in non-alcoholic fatty liver disease patients: From evidence to daily clinical practice, a systematic review

Lifestyle modification comprising calorie restriction (CR) and increased physical activity enabling weight loss is the first-line of treatment for non-alcoholic fatty liver disease (NAFLD). However, CR alone is not optimal and evidence suggests that dietary pattern and composition are also critical in NAFLD management. Accordingly, high consumption of red and processed meat, saturated fat, added sugar, and sweetened beverages are associated with an increased risk of developing NAFLD and hepatocellular carcinoma, while other foods and compounds such as fish, olive oil, and polyphenols are, in contrast, beneficial for metabolic disorders. Therefore, several dietary interventions have been studied in order to determine which strategy would be the most beneficial for NAFLD. The evidence regarding the effectiveness of different dietary interventions such as low carbohydrate/low-fat diet, time-restricted eating diet, CR, and the well-studied Mediterranean diet is summarized.

Physical Activity and Nonalcoholic Fatty Liver Disease: A Roundtable Statement from the American College of Sports Medicine

ABSTRACT

Although physical activity (PA) is crucial in the prevention and clinical management of nonalcoholic fatty liver disease, most individuals with this chronic disease are inactive and do not achieve recommended amounts of PA. There is a robust and consistent body of evidence highlighting the benefit of participating in regular PA, including a reduction in liver fat and improvement in body composition, cardiorespiratory fitness, vascular biology, and health-related quality of life. Importantly, the benefits of regular PA can be seen without clinically significant weight loss. At least 150 min of moderate or 75 min of vigorous intensity PA are recommended weekly for all patients with nonalcoholic fatty liver disease, including those with compensated cirrhosis. If a formal exercise training program is prescribed, aerobic exercise with the addition of resistance training is preferred. In this roundtable document, the benefits of PA are discussed, along with recommendations for 1) PA assessment and screening; 2) how best to advise, counsel, and prescribe regular PA; and 3) when to refer to an exercise specialist.

Nonalcoholic liver disease: Epidemiology, risk factors, natural history, and management strategies

Nonalcoholic fatty liver disease (NAFLD) is now the most common chronic liver disease worldwide and a leading indication for liver transplantation in the United States. NAFLD encompasses a heterogeneous clinicopathologic spectrum, ranging from nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis, and progressive fibrosis, which can lead to end-stage liver disease including cirrhosis and hepatocellular cancer. Predictive models suggest that over 100 million adults in the United States will have NAFLD by 2030, representing over a third of the population. In this manuscript, we provide an overview of NAFLD risk factors, natural history (including hepatic and extra-hepatic outcomes), diagnosis, and current management strategies.

Poor cardiorespiratory fitness may be an indicator of more severe liver inflammation in non-alcoholic fatty liver disease patients

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) is related to cardiovascular disease. Cardiorespiratory fitness (CRF) is an important indicator of cardiovascular health. Therefore, we aimed to evaluate the CRF of NAFLD patients.

METHODS

Cross-sectional study, including 32 patients with biopsy-proved NAFLD. The patients underwent ergometric test (ET) and six-minute walk test (6MWT) to determine CRF. The test results were compared to disease parameters and with each other.

RESULTS

Considering the ET, 20 (62.5%) patients had very poor or poor CRF, and in 12 (37.5%), it was regular or good. In the 6MWT, 13 (40.6%) individuals had poor CRF, in 12 (37.5%), it was very poor, and in seven (21.9%), regular. NAFLD activity score (NAS) ≥5 was observed in 12 (37.5%) individuals. Twelve (37.5%) patients were sedentary, 11 (34.4%), insufficiently active, and nine (28.1%), active. Obesity and liver inflammation on biopsy were associated with very poor/poor CRF. NAS ≥5 and sedentary lifestyle were independently associated with very poor/poor CRF by ET. Although mean VO2max values determined by both tests were similar, no correlation of VO2max determined by ET and 6MWT was observed, as occurred for the distance walked in 6MWT and values of metabolic equivalent (MET) determined by ET. There was no reproducibility between CRF determined by ET and 6MWT.

CONCLUSION

Most NAFLD patients had very poor or poor CRF. Severe liver injury (NAS ≥5) and sedentary lifestyle were independently associated with very poor/poor fitness, according to ET. No reproducibility was observed between the CRF defined by ET and 6MWT.

Effect of Exercise on Liver Function and Insulin Resistance Markers in Patients with Non-Alcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Structured exercise as part of lifestyle modification plays an important role in the improvement of non-alcoholic fatty liver disease (NAFLD); however, its effectiveness has been shown to vary. This systematic review with meta-analysis investigated the effects of exercise on liver function and insulin resistance markers in patients with NAFLD.

METHODS

Six electronic databases were searched using terms related to exercise and NAFLD up to March 2022. Data were analyzed using a random-effects model to estimate the standardized mean difference (SMD) and 95% confidence interval.

RESULTS

The systematic search identified 2583 articles, of which a total of 26 studies met the inclusion criteria and were eligible. Exercise training had a moderate effect on reducing ALT (SMD: -0.59, p = 0.01) and small effects on reducing AST (SMD: -0.40, p = 0.01) and insulin (SMD: -0.43, p = 0.02). Significant reductions in ALT were found following aerobic training (SMD: -0.63, p < 0.01) and resistance training (SMD: -0.45, p < 0.001). Moreover, reductions in AST were found following resistance training (SMD: -0.54, p = 0.001), but not after aerobic training and combined training. However, reductions in insulin were found following aerobic training (SMD: -0.55, p = 0.03). Exercise interventions for <12 weeks compared to ≥12 weeks were more effective in reducing FBG and HOMA-IR, while interventions for ≥12 weeks compared to <12 weeks were more effective in reducing ALT and AST levels.

CONCLUSIONS

Our findings support the effectiveness of exercise in improving liver function markers but not in blood glucose control in NAFLD patients. Additional studies are needed to determine the exercise prescription to maximize health in these patients.

Application of Scores Assessing Histological Activity and Estimated Long-Term Risk Analysis of Hepatic Decompensation of Non-Alcoholic Fatty Liver Disease in Individuals Undergoing Bariatric Surgery

BACKGROUND

Histological scores can estimate disease staging, allowing a standardization of the assessment of non-alcoholic fatty liver disease (NAFLD). The prediction of risk of NAFLD progression is relevant to allow the planning of interventions.

OBJECTIVE

To analyze the application of the Iowa NAFLD decompensation risk score, the NAFLD activity score (NAS), and steatosis-activity-fibrosis score (SAF) and to assess correlations between these scores.

METHODS

This is a retrospective cross-sectional study enrolling 76 individuals who underwent bariatric surgery at a tertiary university hospital. Liver biopsy was performed during procedures; histological scores were then assessed. The Iowa score was calculated using age, diabetes, and platelet count.

RESULTS

89.5% were female and mean age was 39.1 ± 9.6 years. Mean BMI was 38.2 ± 3.7 kg/m². Steatosis (92.1%), hepatocellular ballooning (93.4%), lobular inflammation (93.4%), and fibrosis (97.4%) were the commonest histopathological findings. According to NAS, 22.4% had definite non-alcoholic steatohepatitis (NASH). According to SAF, 89.5% had moderate or severe NAFLD. The mean risks of NAFLD decompensation at 5, 10, and 12 years were 0.8%, 2.5%, and 2.9%, respectively. The group whose risk of decompensation was above 10% comprised 2.6% and 5.3% at 10 and 12 years, respectively. The severity assessed by SAF significantly associated with definite NASH diagnosis through NAS (p < 0.001). Iowa score did not correlate with both NAS/SAF scores.

CONCLUSION

The Iowa score demonstrated that individuals with obesity present with a significant long-term risk of NAFLD-related events. There were high rates of moderate/severe forms of NAFLD assessed by NAS and SAF scores. There were no significant correlations between Iowa and NAS/SAF scores.

Eating, diet, and nutrition for the treatment of non-alcoholic fatty liver disease

Nutrition and dietary interventions are a central component in the pathophysiology, but also a cornerstone in the management of patients with non-alcoholic fatty liver disease (NAFLD). Summarizing our rapidly advancing understanding of how our diet influences our metabolism and focusing on specific effects on the liver, we provide a comprehensive overview of dietary concepts to counteract the increasing burden of NAFLD. Specifically, we emphasize the importance of dietary calorie restriction independently of the macronutrient composition together with adherence to a Mediterranean diet low in added fructose and processed meat that seems to exert favorable effects beyond calorie restriction. Also, we discuss intermittent fasting as a type of diet specifically tailored to decrease liver fat content and increase ketogenesis, awaiting future study results in NAFLD. Finally, personalized dietary recommendations could be powerful tools to increase the effectiveness of dietary interventions in patients with NAFLD considering the genetic background and the microbiome, among others.

The independent effect of exercise on biopsy-proven non-alcoholic fatty liver disease: A systematic review

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. Although previous studies have demonstrated that exercise independently reduces hepatic steatosis measured by imaging modalities in NAFLD, the effect of exercise on histological endpoints remains unclear. We aimed to conduct a systematic review of the independent effect of exercise on hepatic steatosis, steatohepatitis, and liver fibrosis as measured by histological assessment or non-invasive tests (NITs) in biopsy-proven NAFLD. A systematic literature search of PubMed, Embase, and Web of Science databases was performed using keywords related to exercise, NAFLD, and biopsy. Articles were selected based on the following inclusion criteria: (1) involved human subjects with biopsy-proven NAFLD, (2) analyzed the independent effect of exercise, (3) assessed changes in hepatic steatosis, steatohepatitis, or liver fibrosis via either histological evaluation or NITs, and (4) were original research studies. We identified a total of six studies that analyzed the independent effect of exercise on histological endpoints in biopsy-proven NAFLD. Two randomized controlled trials (RCTs) did not detect significant histological improvement following exercise interventions, while other non-randomized interventional studies showed that exercise reduces hepatocyte ballooning and liver fibrosis. In addition, five studies assessed NIT outcomes, collectively demonstrating that exercise improves hepatic steatosis measured by magnetic resonance imaging-based techniques but not serum biomarkers for steatohepatitis and liver fibrosis. Additional large RCTs and meta-analyses are warranted to investigate the independent effect of exercise on histological and clinical outcome endpoints in NAFLD.

High-Intensity Interval Training is Safe, Feasible and Efficacious in Nonalcoholic Steatohepatitis: A Randomized Controlled Trial

BACKGROUND

High-Intensity Interval Training (HIIT) involves bursts of high-intensity exercise interspersed with lower-intensity exercise recovery. HIIT may benefit cardiometabolic health in people with nonalcoholic steatohepatitis (NASH).

AIMS

We aimed to examine the safety, feasibility, and efficacy of 12-weeks of supervised HIIT compared with a sham-exercise control (CON) for improving aerobic fitness and peripheral insulin sensitivity in biopsy-proven NASH.

METHODS

Participants based in the community [(n = 14, 56 ± 10 years, BMI 39.2 ± 6.7 kg/m², 64% male), NAFLD Activity Score 5 (range 3-7)] were randomized to 12-weeks of supervised HIIT (n = 8, 4 × 4 min at 85-95% maximal heart rate, interspersed with 3 min active recovery; 3 days/week) or CON (n = 6, stretching; 3 days/week). Safety (adverse events) and feasibility determined as ≥ 70% program completion and ≥ 70% global adherence (including session attendance, interval intensity adherence, and duration adherence) were assessed. Changes in cardiorespiratory fitness (V̇O₂peak), exercise capacity (time-on-test) and peripheral insulin sensitivity (euglycemic hyperinsulinemic clamp) were assessed. Data were analysed using ANCOVA with baseline value as the covariate.

RESULTS

There were no HIIT-related adverse events and HIIT was globally feasible [program completion 75%, global adherence 100% (including adherence to session 95.4 ± 7.3%, interval intensity 95.3 ± 6.0% and duration 96.8 ± 2.4%)]. A large between-group effect was observed for exercise capacity [mean difference 134.2 s (95% CI 19.8, 248.6 s), ƞ² 0.44, p = 0.03], improving in HIIT (106.2 ± 97.5 s) but not CON (- 33.4 ± 43.3 s), and for peripheral insulin sensitivity [mean difference 3.4 mg/KgLegFFM/min (95% CI 0.9,6.8 mg/KgLegFFM/min), ƞ² 0.32, p = 0.046], improving in HIIT (1.0 ± 0.8 mg/KgLegFFM/min) but not CON (- 3.1 ± 1.2 mg/KgLegFFM/min).

CONCLUSIONS

HIIT is safe, feasible and efficacious for improving exercise capacity and peripheral insulin sensitivity in people with NASH.

CLINICAL TRIAL REGISTRATION NUMBER

Australian New Zealand Clinical Trial Registry (anzctr.org.au) identifier ACTRN12616000305426 (09/03/2016).

Does aerobic exercise reduce NASH and liver fibrosis in patients with non-alcoholic fatty liver disease? A systematic literature review and meta-analysis

Background

Exercise is an effective strategy for the prevention and regression of hepatic steatosis in patients with non-alcoholic fatty liver disease (NAFLD), but it is unclear whether it can reduce advanced stages of NAFLD, i.e., steatohepatitis and liver fibrosis. Furthermore, it is not evident which modality of exercise is optimal to improve/attenuate NAFLD.

Objectives

The aim is to systematically review evidence for the effect of aerobic exercise (AE) on NAFLD, in particular non-alcoholic steatohepatitis (NASH) and liver fibrosis.

Methods

A systematic literature search was conducted in Medline and Embase. Studies were screened and included according to predefined criteria, data were extracted, and the quality was assessed by Cochrane risk of bias tools by two researchers independently according to the protocol registered in the PROSPERO database (CRD42021270059). Meta-analyses were performed using a bivariate random-effects model when there were at least three randomized intervention studies (RCTs) with similar intervention modalities and outcome.

Results

The systematic review process resulted in an inclusion a total of 24 studies, 18 RCTs and six non-RCTs, encompassing 1014 patients with NAFLD diagnosed by histological or radiological findings. Studies were grouped based on the type of AE: moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT). A total of twelve meta-analyses were conducted. Compared to controls, MICT resulted in a mean difference (MD) in the NAFLD biomarkers alanine transaminase (ALT) and aspartate aminotransferase (AST) of -3.59 (CI: -5.60, -1.59, p<0.001) and -4.05 (CI: -6.39, -1.71, p<0.001), respectively. HIIT resulted in a MD of -4.31 (95% CI: -9.03, 0.41, p=0.07) and 1.02 (95% CI: -6.91, 8.94, p=0.8) for ALT and AST, respectively. Moreover, both AE types compared to controls showed a significantly lower magnetic resonance spectroscopy (MRS) determined liver fat with a MD of -5.19 (95% CI: -7.33, -3.04, p<0.001) and -3.41 (95% CI: -4.74, -2.08, p<0.001), for MICT and HIIT respectively. MICT compared to controls resulted in a significantly higher cardiorespiratory fitness (MD: 4.43, 95% CI: 0.31, 8.55, p=0.03).

Conclusion

Liver fat is decreased by AE with a concomitant decrease of liver enzymes. AE improved cardiorespiratory fitness. Further studies are needed to elucidate the impact of different types of AE on hepatic inflammation and fibrosis.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier (CRD42021270059).

Effect of illness uncertainty on alanine transaminase levels and aspartate aminotransferase levels in patients with nonalcoholic fatty liver disease

Patients with nonalcoholic fatty liver disease (NAFLD) have illness uncertainty. The purpose of this longitudinal study was to investigate the effect of the degree of illness uncertainty in patients with NAFLD on liver function values. We conducted a questionnaire survey and collected blood samples from outpatients with NAFLD. The items in the questionnaire were measured for illness uncertainty using the Japanese version of the Mishel Uncertainty in Illness Scale-Community (MUIS-C). Blood samples were collected at baseline and after 1 year. We divided the patients into two groups: one with high illness uncertainty and the other with low illness uncertainty. We then compared changes in alanine transaminase (ALT) and aspartate aminotransferase (AST) levels over time from baseline using multiple regression analysis. This study analyzed 148 patients with NAFLD; 75 were male and 73 were female, with a mean age of 58.4 ± 12.3 years. The group with higher illness uncertainty had significantly higher ALT and AST levels at 1 year (β = .185 and .183, respectively) than the group with lower illness uncertainty. High illness uncertainty in patients with NAFLD can lead to higher ALT and AST levels. Healthcare providers must focus on reducing illness uncertainty in patients with NAFLD.

Efficacy of aerobic and resistance exercises in improving visceral adipose in patients with non-alcoholic fatty liver: a meta-analysis of randomized controlled trials

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a common chronic disease that can cause liver deterioration if insufficiently diagnosed and untreated. The verification of whether exercise interventions improve liver enzymes and lipid and glucose parameters is scant.

AIM

We conducted this systematic review and meta-analysis to examine the efficacy of aerobic and resistance exercise interventions in patients with NAFLD.

METHODS

We searched the related studies in the PubMed, Embase, Cochrane Library, and Web of Science databases. We screened 1129 articles published before September 1, 2021, based on the inclusion and exclusion standards, after which 17 articles with a total of 1168 participants were finally included. The indices of liver enzymes and lipid and glucose metabolism were gathered and examined by Stata SE.

RESULTS

The outcomes suggested that aerobic and resistance exercise can markedly improve the parameters of liver enzymes, blood lipids, and glucose, and especially visceral adipose tissue (weighted mean different [WMD] = -8.3 at 95% CI [-11.59 to -5.00], p < 0.0001), in patients with NAFLD.

CONCLUSION

This study demonstrated that aerobic and resistance exercises positively affect NAFLD treatment. To further quantify the effects on patients with NAFLD, a more specific and uniform exercise program should be proposed.

Body weight loss and glycemic control on the outcomes of patients with NAFLD. The role of new antidiabetic agents

Nonalcoholic fatty liver disease (NAFLD) is currently the most common cause of chronic liver disease worldwide affecting a third of adults and 12% of children in Western countries. In around 50-60%% of cases, NAFLD and type 2 diabetes mellitus (T2DM) coexist and act synergistically to increase the risk of adverse hepatic and extra-hepatic outcomes. T2DM is a strong risk factor for rapid progression of NAFLD to nonalcoholic steatohepatitis (NASH), cirrhosis or hepatocellular carcinoma (HCC), which have become frequent indications of liver transplantation. The pathophysiology of NAFLD is complex and its relationship with T2DM is bidirectional, where lipotoxicity and insulin resistance (IR), act as the strongest pillars. To date, no pharmacological treatment has been approved for NAFLD. However, there is an intense research with numerous drugs focused on reversing inflammation and liver fibrosis through modulation of molecular targets without good results. It has been known for some time that weight reduction >10% is associated to histological improvement of NAFLD. Recently, glycemic control has been shown to induce similar results. Diet and physical exercise for weight reduction have limitations, so alternative methods (pharmacologic, endoscopic or surgical) may be required. Currently, new antidiabetic drugs inducing weight loss, have been recently approved for the treatment of obesity. Nevertheless, their therapeutic effects on NAFLD have not been extensively studied. We will review here, recently published data on the effects of weight loss and glycemic control on the histological and metabolic parameters of NAFLD and recent published data on therapeutic studies of NAFLD with new antidiabetic drugs.

Benefits of Physical Exercise as Approach to Prevention and Reversion of Non-Alcoholic Fatty Liver Disease in Children and Adolescents with Obesity

Non-alcoholic fatty liver disease (NAFLD) is an important health concern during childhood; indeed, it is the most frequent cause of chronic liver diseases in obese children. No valid pharmacological therapies for children affected by this condition are available, and the recommended treatment is lifestyle modification, usually including nutrition and exercise interventions. In this narrative review, we summarized up-to-date information on the benefits of physical exercise on NAFLD in children and adolescents with obesity. The role of exercise as non-pharmacological treatment was emphasized in order to provide recent advances on this topic for clinicians not deeply involved in the field. Several studies on obese children and adults confirm the positive role of physical activity (PA) in the treatment of NAFLD, but to date, there are no pediatric randomized clinical trials on exercise versus usual care. Among the pathogenic mechanisms involved in the PA effects on NAFLD, the main players seem to be insulin resistance and related inflammation, oxidative stress, and gut dysbiosis, but further evaluations are necessary to deeply understand whether these factors are correlated and how they synergistically act. Thus, a deeper research on this theme is needed, and it would be extremely interesting.

Heat Therapy Can Improve Hepatic Mitochondrial Function and Glucose Control

This review proposes the novel hypothesis that heat can be used as an alternative therapy to exercise to improve hepatic mitochondrial function and glucose regulation in patients with nonalcoholic fatty liver disease. Although exercise has proven benefits in treating nonalcoholic fatty liver disease, barriers to exercise in the majority of patients necessitate an alternative method of treatment.

Proteomic analysis reveals exercise training induced remodelling of hepatokine secretion and uncovers syndecan-4 as a regulator of hepatic lipid metabolism

Objective

Non-alcoholic fatty liver disease (NAFLD) is linked to impaired lipid metabolism and systemic insulin resistance, which is partly mediated by altered secretion of liver proteins known as hepatokines. Regular physical activity can resolve NAFLD and improve its metabolic comorbidities, however, the effects of exercise training on hepatokine secretion and the metabolic impact of exercise-regulated hepatokines in NAFLD remain unresolved. Herein, we examined the effect of endurance exercise training on hepatocyte secreted proteins with the aim of identifying proteins that regulate metabolism and reduce NAFLD severity.

Methods

C57BL/6 mice were fed a high-fat diet for six weeks to induce NAFLD. Mice were exercise trained for a further six weeks, while the control group remained sedentary. Hepatocytes were isolated two days after the last exercise bout, and intracellular and secreted proteins were detected using label-free mass spectrometry. Hepatocyte secreted factors were applied to skeletal muscle and liver ex vivo and insulin action and fatty acid metabolism were assessed. Syndecan-4 (SDC4), identified as an exercise-responsive hepatokine, was overexpressed in the livers of mice using adeno-associated virus. Whole-body energy homeostasis was assessed by indirect calorimetry and skeletal muscle and liver metabolism was assessed using radiometric techniques.

Results

Proteomics analysis detected 2657 intracellular and 1593 secreted proteins from mouse hepatocytes. Exercise training remodelled the hepatocyte proteome, with differences in 137 intracellular and 35 secreted proteins. Bioinformatic analysis of hepatocyte secreted proteins revealed enrichment of tumour suppressive proteins and proteins involved in lipid metabolism and mitochondrial function, and suppression of oncogenes and regulators of oxidative stress. Hepatocyte secreted factors from exercise trained mice improved insulin action in skeletal muscle and increased hepatic fatty acid oxidation. Hepatocyte-specific overexpression of SDC4 reduced hepatic steatosis, which was associated with reduced hepatic fatty acid uptake, and blunted pro-inflammatory and pro-fibrotic gene expression. Treating hepatocytes with recombinant ectodomain of SDC4 (secreted form) recapitulated these effects with reduced fatty acid uptake, lipid storage and lipid droplet accumulation.

Conclusions

Remodelling of hepatokine secretion is an adaptation to regular exercise training that induces changes in metabolism in the liver and skeletal muscle. SDC4 is a novel exercise-responsive hepatokine that decreases fatty acid uptake and reduces steatosis in the liver. By understanding the proteomic changes in hepatocytes with exercise, these findings have potential for the discovery of new therapeutic targets for NAFLD.

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Exercise training remodels hepatokine secretion.

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Exercise regulated secreted factors improve insulin action in skeletal muscle.

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Syndecan-4 (SDC4) is a novel exercise-induced hepatokine.

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SDC4 reduces hepatic fatty acid uptake and hepatic steatosis.

Effect of rosemary leaf powder with weight loss diet on lipid profile, glycemic status, and liver enzymes in patients with nonalcoholic fatty liver disease: A randomized, double-blind clinical trial

Experimental and some clinical studies have shown beneficial effects of rosemary leaf on liver function and biochemical parameters. The present study aimed to examine the impact of rosemary leaf powder with a weight loss diet in patients with nonalcoholic fatty liver disease. In a randomized double-blinded clinical trial, 110 patients were randomly assigned to receive either 4 g rosemary leaf or placebo (starch) powders for 8 weeks. In addition, all participants in the study were given weight loss diet and physical activity recommendations. Compared with baseline, alanine aminotransferase (p < .001), aspartate aminotransferase (p < .001), alkaline phosphatase (p < .001), gamma glutamyltransferase (p < .001), fasting blood glucose (p < .001), fasting insulin (p < .001), insulin resistance (p < .001), total cholesterol (p = .003), triglyceride (p < .001), low-density lipoprotein cholesterol (p < .001), and anthropometric indices (weight, body mass index, and waist circumferences) decreased significantly in the rosemary and placebo group with weight loss. However, after 8 weeks, no significant difference between the rosemary and placebo groups was detected in the variables as mentioned above except homeostasis model assessment of β-cell dysfunction (p = .014). The findings of the current clinical trial study revealed that rosemary group did produce changes, but they were not statistically different from those produced by the diet/activity intervention alone.

Lifestyle changes in patients with non-alcoholic fatty liver disease: A systematic review and meta-analysis

BACKGROUND

Non-alcoholic fatty liver disease is a liver condition that is increasing worldwide and expected to become the number one cause of cirrhosis and hepatocellular carcinoma in the next 5 years. Currently there are no successful or approved pharmacological treatments. Weight loss is the first-line therapy as a 7 to 10% reduction improves steatosis, inflammation, hepatocyte ballooning, and fibrosis. To achieve this, lifestyle interventions including daily exercise and diet must be encouraged. We aimed to assess the effects of diet, exercise, or a combination of both compared to conventional treatment in patients with non-alcoholic fatty liver disease.

METHODS AND FINDING

A literature search was performed in CENTRAL, EMBASE, and PubMed. Randomized controlled trials comparing lifestyle changes with conventional treatment were included, without date restriction. Two authors searched studies according to eligibility criteria, extracted data, and assessed study quality. Subgroup analysis was made by type of intervention, duration of intervention and supervision. We calculated mean differences between the intervention and the control group with their corresponding 95% confidence intervals. Quality of the evidence was assessed using the Cochrane Risk of bias tool. This study is registered in PROSPERO, number CRD42020184241, and checked with the PRISMA checklist. 30 RCTs met the inclusion criteria. Compared to conventional treatment, combined exercise with diet seems to elicit greater reductions in ALT (MD: -13.27 CI 95% -21.39, -5.16), AST (MD: -7.02 CI 95% -11.26, -2.78) and HOMA-IR (MD: -2.07 CI 95% -2.61, -1.46) than diet (ALT MD: -4.48 CI 95% -1.01, -0.21; HOMA-IR MD: -0.61 CI 95% -1.01, -0.21) and exercise (ALT and AST non-significant; HOMA-IR MD = -0.46 CI 95% -0.8, -0.12) alone. Additionally, exercise improved quality of life, cardiorespiratory fitness, and weight (MD: -2.64 CI 95% -5.18, -0.09).

CONCLUSION

Lifestyle changes are effective in the treatment of NAFLD. Diet and exercise combined are superior to these interventions alone in improving liver enzymes and HOMA-IR.

Effect of Aerobic Exercise Alone or in Conjunction With Diet on Liver Function, Insulin Resistance and Lipids in Non-Alcoholic Fatty Liver Disease

BACKGROUND

Physical exercises are the first step of therapy for people with non-alcoholic fatty liver disease (NAFLD).

OBJECTIVE

The purpose of this meta-analysis is to evaluate the efficacy of aerobic exercise training with or without diet to ameliorate liver function, insulin resistance, and lipids in adults.

DATA SOURCES

We searched relevant databases up to 10 June 2021 for conducting a systematic review and meta-analysis of controlled trials lasting 4 or more weeks that investigated the effects of aerobic exercise alone or accompanied by diet on change in liver enzymes, intrahepatic fat (IHF), insulin resistance, and lipids.

RESULTS

Sixteen studies including 2255 participants were included. There was a significant pooled weighted mean differences (MD) for the comparison between aerobic exercise versus control in alanine aminotransferase (ALT; p = 0.003), aspartate aminotransferase (AST; p = 0.006), IHF (p = 0.0004), body mass (p = 0.0003), and body mass index (p = 0.004). Moreover, there was a significant pooled MD for the comparison between aerobic exercise plus diet versus control in ALT (p < 0.0001), AST (p = 0.01), IHF (p = 0.02), GGT (p < 0.00001), insulin (p < 0.0001), HOMA-IR (p < 0.00001), body mass (p < 0.0001), and BMI (p = 0.01).

CONCLUSION

Our findings demonstrate a role for aerobic exercise with and without diet protocol as a therapeutic purpose, and suggest that evaluation of aerobic training levels and aerobic training prescription plus diet should be routine in NAFLD.

Mitigation of MAFLD in High Fat-High Sucrose-Fructose Fed Mice by a Combination of Genistein Consumption and Exercise Training

PURPOSE

Metabolic dysfunction-associated fatty liver disease (MAFLD) is fueled by escalations in both sedentary behavior and caloric intake and is noted in obese type 2 diabetic (T2DM) patients. This study aimed to examine the effects of exercise and the phytoestrogen genistein in mice fed a high fat (60% fat) high sugar (55% fructose with 45% sucrose), HFHS diet.

METHODS

Male C57BL/6J mice were assigned to five groups: HFHS, HFHS with genistein (600 mg/kg diet, HFHS+Gen), HFHS with moderate exercise (HFHS+Ex), and HFHS with combined genistein and moderate exercise (HFHS-Gen+Ex). Control lean mice were fed standard chow and water. Exercise consisted of 30-minute sessions of treadmill running five days/week for the 12-week study duration. Body weight was assessed weekly. Liver, kidney, fecal pellets and serum were extracted at the end of the study and maintained at -80°C.

RESULTS

After 12 weeks of treatment, mice in the HFHS group had the highest hepatic lipid content. Plasma levels of glucose, insulin, leptin, cholesterol, amylin, and total fat content were significantly elevated in HFHS mice compared to control mice. HFHS feeding increased protein expression of carnitine palmitoyltransferase 1b (CPT-1b isoform) in gastrocnemius, CPT1a, glucose transporter protein 2 (GLUT2), glucocorticoid receptor (GR), and fructose 1,6-bisphosphate 1 (FBP1) expression in liver. Exercise alone had minor effects on these metabolic abnormalities. Genistein alone resulted in improvements in body weight, fat content, amylin, insulin sensitivity, and liver histopathology, GR, FBP1, and acetyl-CoA carboxylase 1 (ACC1). Combination treatment resulted in additional metabolic improvements, including reductions in hepatic lipid content and lipid area, alanine transferase activity, CPT1b, and CPT1a.

CONCLUSION

Our results indicate that a HFHS diet is obesogenic, inducing metabolic perturbations consistent with T2DM and MAFLD. Genistein alone and genistein combined with moderate intensity exercise were effective in reducing MAFLD and the aberrations induced by chronic HFHS feeding.

Role of aerobic exercise in ameliorating NASH: Insights into the hepatic thyroid hormone signaling and circulating thyroid hormones

AIM

Triiodothyronine (T3) administration significantly eliminates hepatic steatosis and also has a therapeutic effect on non-alcoholic steatohepatitis (NASH). However, the potential mechanism by which T3-mediated exercise improves NASH is unknow. This study aimed to explore the effect of aerobic exercise on liver injury in NASH.

METHODS

Aerobic exercise was conducted to explore the effects of exercise on liver injury in NASH model induced by Atherosclerotic (Ath) diet. Biochemical evaluations, histological staining and real-time PCR were first applied to confirm the amelioration effects of exercise on NASH. RNA-sequencing (RNA-seq) analysis for livers of each group were further used to identify the underlying mechanisms of aerobic exercise. Bioinformatics methods were used to explore the key functional pathways involved in the improvement of liver tissue in NASH mice by aerobic exercise.

RESULTS

Aerobic exercise improved hepatic steatosis, lobular inflammation and fibrosis in NASH mice. multiple inflammation-related pathways were significantly enriched in the liver of NASH group and improved by aerobic exercise. The results of gene set variation analysis (GSVA) showed a higher enrichment score of T3 response signature in NASH mice with exercise. Increased Dio1 expression in the liver of NASH with exercise mice and increased circulating FT3 and FT4 levels upon aerobic exercise were confirmed.

CONCLUSIONS

We found that aerobic exercise could significantly reduce hepatic lipid accumulation, inflammatory infiltration and fibrosis progression in the liver of NASH mice. Hepatic thyroid hormone signaling activation and circulating thyroid hormones is potentially involved in the amelioration effect of aerobatic exercise on NASH progression.

Effect of exercise and diet intervention in NAFLD and NASH via GAB2 methylation

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a disorder that extends from simple hepatic steatosis to nonalcoholic steatohepatitis (NASH), which is effectively alleviated by lifestyle intervention. Nevertheless, DNA methylation mechanism underling the effect of environmental factors on NAFLD and NASH is still obscure. The aim of this study was to investigate the effect of exercise and diet intervention in NAFLD and NASH via DNA methylation of GAB2.

METHODS

Methylation of genomic DNA in human NAFLD was quantified using Infinium Methylation EPIC BeadChip assay after exercise (Ex), low carbohydrate diet (LCD) and exercise plus low carbohydrate diet (ELCD) intervention. The output Idat files were processed using ChAMP package. False discovery rate on genome-wide analysis of DNA methylation (q < 0.05), and cytosine-guanine dinucleotides (CpGs) which are located in promoters were used for subsequent analysis (|Δβ|≥ 0.1). K-means clustering was used to cluster differentially methylated genes according to 3D genome information from Human embryonic stem cell. To quantify DNA methylation and mRNA expression of GRB2 associated binding protein 2 (GAB2) in NASH mice after Ex, low fat diet (LFD) and exercise plus low fat diet (ELFD), MassARRAY EpiTYPER and quantitative reverse transcription polymerase chain reaction were used.

RESULTS

Both LCD and ELCD intervention on human NAFLD can induce same DNA methylation alterations at critical genes in blood, e.g., GAB2, which was also validated in liver and adipose of NASH mice after LFD and ELFD intervention. Moreover, methylation of CpG units (i.e., CpG_10.11.12) inversely correlated with mRNA expression GAB2 in adipose tissue of NASH mice after ELFD intervention.

CONCLUSIONS

We highlighted the susceptibility of DNA methylation in GAB2 to ELFD intervention, through which exercise and diet can protect against the progression of NAFLD and NASH on the genome level, and demonstrated that the DNA methylation variation in blood could mirror epigenetic signatures in target tissues of important biological function, i.e., liver and adipose tissue. Trial registration International Standard Randomized Controlled Trial Number Register (ISRCTN 42622771).

Management of Obesity and Nonalcoholic Fatty Liver Disease: A Literature Review

With the recent urbanization and globalization, the adult obesity rate has been increasing, which was paralleled with a dramatic surge in the incidence and prevalence of nonalcoholic fatty liver disease (NAFLD). NAFLD poses a growing threat to human health as it represents the most common cause of chronic liver disease in developed countries. It encompasses a wide spectrum of conditions starting from a build-up of fat in hepatocytes (steatosis), to developing inflammation (steatohepatitis), and reaching up to cirrhosis. It is also associated with higher rates of cardiovascular mortalities. Therefore, proper timely treatment is essential and weight loss remains the cornerstone in the treatment of obesity-related liver diseases. When diet, exercise, and lifestyle changes are not successful, the current recommendation for weight loss includes antiobesity medications and bariatric endoscopic and surgical interventions. These interventions have shown to result in significant weight loss and improve liver steatosis and fibrosis. In the current literature review, we highlight the expected outcomes and side effects of the currently existing options to have a weight-centric NAFLD approach.

The effect of a Mediterranean diet vs. a low-fat diet on non-alcoholic fatty liver disease in children: a randomized trial

Non-alcoholic fatty liver disease (NAFLD) is becoming ever more common in children, due to the increasing global prevalence of obesity. The first-line treatment consists of weight loss through a combination of a healthy diet and exercise. The objective of this study was to determine the effects of a Mediterranean Diet or a low-fat diet on reducing hepatic steatosis and insulin resistance in children with NAFLD. This 12-week randomised clinical trial was conducted with children aged 9-17 years diagnosed with NAFLD and randomised into either a Mediterranean Diet or a low-fat diet group. By the end of the study, hepatic steatosis had decreased significantly in both groups (p < 0.001). Liver enzymes also improved significantly, while significant decreases were observed in insulin resistance in both groups, although this decrease was greater in the Mediterranean Diet group (p = 0.010). This study demonstrated that a decrease in hepatic steatosis and an improvement in insulin sensitivity can be achieved with both a Mediterranean Diet and a low-fat diet over 12 weeks, with no significant decrease in the energy required for growth, in children with NAFLD.

Probiotic and prebiotic interventions for non-alcoholic fatty liver disease: a systematic review and network meta-analysis

Many studies have associated altered intestinal bacterial communities and non-alcoholic fatty liver disease, but the putative effects are inconclusive. The purpose of this network meta-analysis (NMA) was to evaluate the effects of probiotics, prebiotics, and synbiotics on non-alcoholic fatty liver disease through randomised intervention trials. Literature searches were performed until March 2020. For each outcome, a random NMA was performed, the surface under the cumulative ranking curve (SUCRA) was determined. A total of 22 randomised trials comparing prebiotic, probiotic, and synbiotic treatments included 1301 participants. Considering all seven results (aspartate aminotransferase, alanine aminotransferase, body mass index, weight, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol) together, the highest SUCRA values are probiotics (94%), synbiotics (61%) and prebiotics (56%), respectively. NMA results provide evidence that probiotics, prebiotics, and synbiotics can alleviate non-alcoholic fatty liver disease. However, due to the lack of high-quality randomised trials, this research also has some limitations.

Acute Oral Toxicity Evaluation of Andrographolide Self-Nanoemulsifying Drug Delivery System (SNEDDS) Formulation

Context:

Andrographolide (AND) is an active compound of well-known medicinal plant Andrographis paniculata. It has been widely published for various activities. AND is difficult to develop into dosage form due to its poor solubility and bioavailability. This problem could be solved by using self-nanoemulsifying drug delivery system (SNEDDS) for its formulation. However, the increase of bioavailability might result in potential toxicity as a large amount of drug is absorbed.

Aims:

The aim of this study is to evaluate the acute potential toxicity using Organization for Economic Cooperation and Development (OECD) test: 401 methods.

Subjects and Methods:

The OECD 401 method employs groups of animals treated by a single dose or repeated dose (<24 h) of the drug with three variances of doses. In this study, thirty male Wistar rats were divided into five groups which consisted two groups of control and three groups of AND SNEDDS formulation (500, 700, and 900 mg/kg body weight [BW], respectively). Intensive observation of toxicity symptom was performed during the first 30 minutes followed by periodic observation for 14 days. Posttermination, histopathological examination of the liver and kidney was conducted to confirm the toxicity symptoms. To determine the level of toxicity, the lethal dose 50 (LD₅₀) value was calculated at the end of the study.

Results:

The result showed that all groups presented similar toxicological symptoms such as salivation, lethargy, and cornea reflex. However, based on histopathological examination, there were abnormalities, but still in an early stage. The toxicological symptom that emerged seems related to the SNEDDS formulation with lipophilic properties. Furthermore, the value of LD₅₀ was 832.6 mg/kg BW (po).

Conclusions:

The AND SNEDDS formulation was slightly toxic in male Wistar rats po.

Clinical impact of sexual dimorphism in non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH)

NAFLD/NASH is a sex-dimorphic disease, with a general higher prevalence in men. Women are at reduced risk of NAFLD compared to men in fertile age, whereas after menopause women have a comparable prevalence of NAFLD as men. Indeed, sexual category, sex hormones and gender habits interact with numerous NAFLD factors including cytokines, stress and environmental factors and alter the risk profiles and phenotypes of NAFLD. In the present review, we summarized the last findings about the influence of sex on epidemiology, pathogenesis, progression in cirrhosis, indication for liver transplantation and alternative therapies, including lifestyle modification and pharmacological strategies. We are confident that an appropriate consideration of sex, age, hormonal status and sociocultural gender differences will lead to a better understanding of sex differences in NAFLD risk, therapeutic targets and treatment responses and will aid in achieving sex-specific personalized therapies.

Lifestyle modifications for nonalcohol-related fatty liver disease: a network meta-analysis

BACKGROUND

The prevalence of nonalcohol-related fatty liver disease (NAFLD) varies between 19% and 33% in different populations. NAFLD decreases life expectancy and increases the risks of liver cirrhosis, hepatocellular carcinoma, and requirement for liver transplantation. There is uncertainty surrounding the relative benefits and harms of various lifestyle interventions for people with NAFLD.

OBJECTIVES

To assess the comparative benefits and harms of different lifestyle interventions in the treatment of NAFLD through a network meta-analysis, and to generate rankings of the different lifestyle interventions according to their safety and efficacy.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, Conference Proceedings Citation Index - Science, World Health Organization International Clinical Trials Registry Platform, and trials registers until February 2021 to identify randomised clinical trials in people with NAFLD.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or status) in people with NAFLD, whatever the method of diagnosis, age, and diabetic status of participants, or presence of non-alcoholic steatohepatitis (NASH). We excluded randomised clinical trials in which participants had previously undergone liver transplantation.

DATA COLLECTION AND ANALYSIS

We planned to perform a network meta-analysis with OpenBUGS using Bayesian methods and to calculate the differences in treatments using hazard ratios (HRs), odds ratios (ORs), and rate ratios (RaRs) with 95% credible intervals (CrIs) based on an available-participant analysis, according to National Institute of Health and Care Excellence Decision Support Unit guidance. However, the data were too sparse for the clinical outcomes. We therefore performed only direct comparisons (head-to-head comparisons) with OpenBUGS using Bayesian methods.

MAIN RESULTS

We included a total of 59 randomised clinical trials (3631 participants) in the review. All but two trials were at high risk of bias. A total of 33 different interventions, ranging from advice to supervised exercise and special diets, or a combination of these and no additional intervention were compared in these trials. The reference treatment was no active intervention. Twenty-eight trials (1942 participants) were included in one or more comparisons. The follow-up ranged from 1 month to 24 months. The remaining trials did not report any of the outcomes of interest for this review. The follow-up period in the trials that reported clinical outcomes was 2 months to 24 months. During this short follow-up period, clinical events related to NAFLD such as mortality, liver cirrhosis, liver decompensation, liver transplantation, hepatocellular carcinoma, and liver-related mortality were sparse. This is probably because of the very short follow-up periods. It takes a follow-up of 8 years to 28 years to detect differences in mortality between people with NAFLD and the general population. It is therefore unlikely that differences by clinical outcomes will be noted in trials with less than 5 years to 10 years of follow-up. In one trial, one participant developed an adverse event. There were no adverse events in any of the remaining participants in this trial, or in any of the remaining trials, which seemed to be directly related to the intervention.

AUTHORS' CONCLUSIONS

The evidence indicates considerable uncertainty about the effects of the lifestyle interventions compared with no additional intervention (to general public health advice) on any of the clinical outcomes after a short follow-up period of 2 months to 24 months in people with nonalcohol-related fatty liver disease. Accordingly, high-quality randomised clinical trials with adequate follow-up are needed. We propose registry-based randomised clinical trials or cohort multiple randomised clinical trials (a study design in which multiple interventions are trialed within large longitudinal cohorts of participants to gain efficiencies and align trials more closely to standard clinical practice), comparing aerobic exercise and dietary advice versus standard of care (exercise and dietary advice received as part of national health promotion). The reason for the choice of aerobic exercise and dietary advice is the impact of these interventions on indirect outcomes which may translate to clinical benefit. The outcomes in such trials should be mortality, health-related quality of life, decompensated liver cirrhosis, liver transplantation, and resource use measures including costs of intervention and decreased healthcare use after a minimum follow-up of eight years, to find meaningful differences in the clinically important outcomes.

Lycium barbarum polysaccharide combined with aerobic exercise ameliorated nonalcoholic fatty liver disease through restoring gut microbiota, intestinal barrier and inhibiting hepatic inflammation

Gut microbiota and intestinal permeability have been demonstrated to be the key players in the gut-liver cross talk in nonalcoholic fatty liver disease (NAFLD). Lycium barbarum polysaccharides (LBPs), which seem to be a potential prebiotic, and aerobic exercise (AE) have shown protective effects on NAFLD. However, their combined effects on intestinal microecology remain unclear. This study evaluated the effects of LBP, AE, and its combination (LBP + AE) on gut microbiota composition, intestinal barrier, and hepatic inflammation in NAFLD. LBP + AE showed high abundance and diversity of gut microbiota, restored the gut microbiota composition, increased some Bacteroidetes, short chain fatty acids, but decreased Proteobacteria and the ratio of Firmicutes/Bacteroidetes. Simultaneously, LBP, AE, and LBP + AE could restore the colonic and ileum tight junctions by increasing the expression of zonula occludens-1 and occludin. They also downregulated gut-derived lipopolysaccharides (LPSs), hepatic LPS-binding proteins, inflammatory factors, and related indicators of the LPS/TLR4/NF-κB signaling pathway for the liver. Our results implied that LBP could be considered a prebiotic agent, and LBP + AE might be a promising treatment for NAFLD because it could maintain gut microbiota balance, thereby restoring intestinal barrier and exerting hepatic benefits.

Evidence-Based Aerobic Exercise Training in Metabolic-Associated Fatty Liver Disease: Systematic Review with Meta-Analysis

Background: This meta-analysis evaluates the overall effect of the non-pharmacological intervention, aerobic exercise, upon serum liver enzymes levels, glucose metabolism and anthropometric measures amongst patients with metabolic associated fatty liver disease (MAFLD). It also examines whether the effects on these outcomes are moderated by the aerobic training protocol when considered according to the American College of Sports Medicine (ACSM) recommended FITT (frequency, intensity, time, type) principles. Approach and Results: Fifteen randomized control trials were included in the meta-analysis. Compared with usual care, continuous and interval training showed significant efficacy in alanine aminotransferase (ALT) level improvement (MD = −2.4, 95% CI: −4.34 to −0.46 p = 0.015, I² = 9.1%). Interventions based on all types of aerobic exercise protocols showed significant improvement of intrahepatic triglycerides (MD = −4.0557, 95% CI: −5.3711 to −2.7403, p < 0.0001, I² = 0%) and BMI (MD = −0.9774, 95% CI: −1.4086 to −0.5462, p < 0.0001, I² = 0). Meta-regression analysis demonstrated a significant correlation between total intervention time and ALT level (for all aerobic protocols: 6.0056, se = 2.6896, z = 2.2329, p = 0.02; as well as for continuous and interval aerobic protocols: 5.5069, se = 2.7315, z = 2.016, p = 0.04). Conclusions: All types of aerobic exercise protocols are effective at improving intrahepatic triglycerides and lead to a reduction in body mass index. In addition, continuous and interval aerobic exercise may be more effective at improving ALT ≤12 weeks intervention time benefits the management of MAFLD.

NAFLD and Physical Exercise: Ready, Steady, Go!

Along with the increase in obesity and type 2 diabetes, the non-alcoholic fatty liver disease (NAFLD) incidence is escalating, thus becoming a leading cause of liver cirrhosis and a significant burden of liver-related outcomes. Since there is no pharmacotherapy available to address the NAFLD, the most effective solutions seem to be lifestyle changes centered on physical activity. Exercise could mediate its beneficial effects directly on the liver and indirectly via extrahepatic pathways, forming a dose-response relationship with NAFLD in terms of prevalence and disease severity. Health-enhancing physical activity (HEPA) levels are mainly needed to exert beneficial effects in obese subjects, while even a small amount of exercise can be beneficial for lean individuals to prevent NAFLD. This mini-review addresses three major points regarding physical activity and NAFLD: prevention, treatment, and extrahepatic benefits, offering recommendations on type and intensity of exercise in liver disease.

Cirrhosis and insulin resistance: current knowledge, pathophysiological mechanisms, complications and potential treatments

End-stage chronic liver diseases are often associated with insulin resistance (IR) and diabetes mellitus (DM). Indeed, to quantify insulin sensitivity the euglycemic clamp technique was utilized, allowing the following to be stated: in small groups of patients, an IR in almost all cirrhotic patients can be observed, compared with a control group. Additionally, it has been demonstrated that IR in cirrhosis is linked to a decreased peripheral (muscle) glucose uptake rather than an increased liver glucose production. The homoeostasis model of IR (HOMA-IR) technique, devised only later, was then exploited to assess this same phenomenon in a larger sample population. The research established that even in patients with preserved liver function, cirrhosis is associated with significant alterations in glucose homoeostasis levels. The purpose of the present paper is to present the current research around the affiliation of cirrhosis and IR, discuss potential mechanisms explaining the association between cirrhosis and IR (i.e. endocrine perturbation, liver inflammation, altered muscle mass and composition, altered gut microbiota and permeability), complications that can arise as well as treatment options, through a critical review of the literature surrounding this subject. This research will also be investigating the beneficial impact, if there is any, of identifying and curing IR in patients with cirrhosis.

Non-Alcoholic Steatohepatitis: A Review of Its Mechanism, Models and Medical Treatments

Non-alcoholic steatohepatitis (NASH) develops from non-alcoholic fatty liver disease (NAFLD). Currently, around 25% of the population is estimated to have NAFLD, and 25% of NAFLD patients are estimated to have NASH. NASH is typically characterized by liver steatosis inflammation, and fibrosis driven by metabolic disruptions such as obesity, diabetes, and dyslipidemia. NASH patients with significant fibrosis have increased risk of developing cirrhosis and liver failure. Currently, NASH is the second leading cause for liver transplant in the United States. More importantly, the risk of developing hepatocellular carcinoma from NASH has also been highlighted in recent studies. Patients may have NAFLD for years before progressing into NASH. Although the pathogenesis of NASH is not completely understood, the current “multiple-hits” hypothesis suggests that in addition to fat accumulation, elevated oxidative and ER stress may also drive liver inflammation and fibrosis. The development of clinically relevant animal models and pharmacological treatments for NASH have been hampered by the limited understanding of the disease mechanism and a lack of sensitive, non-invasive diagnostic tools. Currently, most pre-clinical animal models are divided into three main groups which includes: genetic models, diet-induced, and toxin + diet-induced animal models. Although dietary models mimic the natural course of NASH in humans, the models often only induce mild liver injury. Many genetic and toxin + diet-induced models rapidly induce the development of metabolic disruption and serious liver injury, but not without their own shortcomings. This review provides an overview of the “multiple-hits” hypothesis and an evaluation of the currently existing animal models of NASH. This review also provides an update on the available interventions for managing NASH as well as pharmacological agents that are currently undergoing clinical trials for the treatment of NASH.

Clinical assessment and management of liver fibrosis in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is among the most frequent etiologies of cirrhosis worldwide, and it is associated with features of metabolic syndrome; the key factor influencing its prognosis is the progression of liver fibrosis. This review aimed to propose a practical and stepwise approach to the evaluation and management of liver fibrosis in patients with NAFLD, analyzing the currently available literature. In the assessment of NAFLD patients, it is important to identify clinical, genetic, and environmental determinants of fibrosis development and its progression. To properly detect fibrosis, it is important to take into account the available methods and their supporting scientific evidence to guide the approach and the sequential selection of the best available biochemical scores, followed by a complementary imaging study (transient elastography, magnetic resonance elastography or acoustic radiation force impulse) and finally a liver biopsy, when needed. To help with the selection of the most appropriate method a Fagan's nomogram analysis is provided in this review, describing the diagnostic yield of each method and their post-test probability of detecting liver fibrosis. Finally, treatment should always include diet and exercise, as well as controlling the components of the metabolic syndrome, +/- vitamin E, considering the presence of sleep apnea, and when available, allocate those patients with advanced fibrosis or high risk of progression into clinical trials. The final end of this approach should be to establish an opportune diagnosis and treatment of liver fibrosis in patients with NAFLD, aiming to decrease/stop its progression and improve their prognosis.