High cardiorespiratory fitness is an independent predictor of the reduction in liver fat during a lifestyle intervention in non-alcoholic fatty liver disease

Lifestyle intervention for metabolic dysfunction-associated fatty liver disease: a 24-h integrated behavior perspective

INTRODUCTION

The prevalence, health and socioeconomic burden of metabolic dysfunction-associated fatty liver disease (MAFLD) is growing, increasing the need for novel evidence-based lifestyle approaches. Lifestyle is the cornerstone for MAFLD management and co-existing cardiometabolic dysfunction. The aim of this review was to evaluate the evidence for lifestyle management of MAFLD, with a specific lens on 24-hour integrated behaviour and provide practical recommendations for implementation of the evidence.

RESULTS

Weight loss ≥ 7-10% is central to lifestyle management; however, liver and cardiometabolic benefits are attainable with improved diet quality and exercise even without weight loss. Lifestyle intervention for MAFLD should consider an integrated '24-h' approach that is cognisant of diet, physical activity/exercise, sedentary behavior, smoking, alcohol intake and sleep. Dietary management emphasises energy deficit and improved diet quality, especially the Mediterranean diet, although sociocultural adaptations to meet preferences should be considered. Increasing physical activity and reducing sedentary behavior can prevent MAFLD, with strongest evidence in MAFLD supporting regular structured moderate-vigorous aerobic exercise for 150-240 min/week. Resistance training in addition to aerobic exercise should be considered and prioritised for those who are losing body mass via diet and/or pharmacological approaches and those with sarcopenia, to minimise bone and lean mass loss. Limited evidence suggests that sleep is important for MAFLD prevention. Emerging novel approaches to diet and exercise may address some of the key barriers to behaviour change (e.g. lack of time, access to resources and social support).

FUTURE DIRECTIONS

Large-scale multidisciplinary trials in people with MAFLD with long-term follow-up, that can be scaled up into mainstream healthcare, are required. Future management guidelines should consider the heterogeneity of MAFLD and specialised models of care that coordinate the health workforce to manage the increased and growing MAFLD population.

The effectiveness of multidisciplinary weight loss interventions is associated with initial cardiorespiratory fitness in adolescents with obesity

BACKGROUND

The identification of predictive parameters of the success of multidisciplinary weight loss interventions (MWLI) appears essential to optimize obesity management. The association between baseline cardiorespiratory fitness (CRF) and changes in anthropometric parameters and body composition during MWLI remains underexplored in adolescents with obesity.

OBJECTIVES

To assess whether baseline CRF was associated with the effectiveness of a 16-week MWLI measured through improved body mass, body mass index (BMI) and body composition (percentage of total fat mass (FM) as the main criterion).

METHODS

Cardiorespiratory fitness and body composition were respectively measured by peak oxygen consumption (VO2peak) during maximal exercise tests and dual-photon x-ray absorptiometry (DXA), before (T0) and after (T1) a 16-week MWLI in 165 adolescents (aged 13.3 ± 1.38 years, 61.2% female, BMI 35.11 ± 5.16 kg/m2).

RESULTS

Reductions in BMI and total FM percentage between T0 and T1 were greater in subjects with a baseline VO2peak ≥ 3rd quartile compared to the first quartile (p < 0.001) and the interquartile range (p < 0.05 and p < 0.001, respectively). Baseline VO2peak and VO2 at the first ventilator threshold were positively correlated with the reductions in body mass, BMI and total and visceral FM percentages and with the increase in lean mass (LM) percentage between T0 and T1 after adjustment for age and gender (p < 0.001).

CONCLUSION

Initial CRF is associated with the success of MWLI in adolescents with obesity. Improving their aerobic fitness before starting a MWLI might be a promising strategy to optimize its benefits.

Effects of a Two-Year Lifestyle Intervention on Intrahepatic Fat Reduction and Renal Health: Mitigation of Inflammation and Oxidative Stress, a Randomized Trial

Metabolic-associated fatty liver disease (MAFLD) is the most common chronic liver disease observed in clinical practice worldwide. This disorder has been independently associated with an increased risk of developing chronic kidney disease (CKD). The aim of this study was to evaluate whether a 2-year intervention based on a Mediterranean diet (MedDiet) and physical activity focussed on reducing intrahepatic fat contents (IFC) was associated with a decreased risk of CKD. Forty adults (50% women) residing in Mallorca, aged 48 to 60 years, diagnosed with MAFLD were recruited. Participants were divided into two groups based on whether they improved IFC measured by nuclear magnetic resonance. Anthropometric and clinical parameters improved in responders, including reduced weight, body mass index (BMI), and waist circumference. Only responders showed improvements in lipid profile and liver enzymes. Haematological parameters showed favourable changes in both groups. Oxidative stress and inflammatory biomarkers differed between groups. Responders had lower plasma interleukine-18 (IL-18) levels, but higher erythrocyte malonaldehyde (MDA) levels. Non-responders showed increased erythrocyte catalase and superoxide dismutase activity. After 2 years, non-responders had higher serum creatinine, Modification of Diet in Renal Disease (MDRD), and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) levels, while responders showed reductions in these parameters together with uric acid and urine albumin-to-creatinine ratio (UACR). Positive correlations were found between changes in IFC and kidney injury biomarkers, including MDRD and serum creatinine levels. In conclusion, a healthy diet based on the Mediterranean dietary pattern and lifestyle promotes significant improvements in parameters related to cardiovascular, hepatic, and renal health.

Effect of sustained decreases in sedentary time and increases in physical activity on liver enzymes and indices in type 2 diabetes

Background

Current guidelines for nonalcoholic fatty liver disease (NAFLD) recommend high volumes and/or intensities of physical activity (PA), the achievement of which generally requires participation in supervised exercise training programs that however are difficult to implement in routine clinical practice. Conversely, counselling interventions may be more suitable, but result in only modest increases in moderate-to-vigorous-intensity PA (MVPA). This study assessed whether a counseling intervention for increasing PA and decreasing sedentary time (SED-time) is effective in improving NAFLD markers in people with type 2 diabetes.

Methods

Three-hundred physically inactive and sedentary patients were randomized 1:1 to receive one-month theoretical and practical counseling once-a-year (intervention group) or standard care (control group) for 3 years. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), and γ-glutamyltranspeptidase (γGT) levels were measured and fatty liver index (FLI), hepatic steatosis index (HSI), and visceral adiposity index (VAI) were calculated. Total PA volume, light-intensity PA (LPA), moderate-to-vigorous-intensity PA (MVPA), and SED-time were objectively measured by an accelerometer.

Results

Throughout the 3-year period, NAFLD markers did not change in the control group, whereas ALT, γGT, FLI, and HSI decreased in the intervention group, with significant between-group differences, despite modest MVPA increases, which however were associated with larger decrements in SED-time and reciprocal increments in LPA. Mean changes in NAFLD markers varied according to quartiles of (and correlated with) changes in MVPA (all markers) and SED-time, LPA, and PA volume (ALT, γGT, and HSI). Mean changes in MVPA or PA volume were independent predictors of changes in NAFLD markers. When included in the models, change in cardiorespiratory fitness and lower body muscle strength were independently associated with some NAFLD markers.

Conclusion

A behavior change involving all domains of PA lifestyle, even if insufficient to achieve the recommended MVPA target, may provide beneficial effects on NAFLD markers in people with type 2 diabetes.

Prevalence, Risk Factors, and Metabolic Characteristics of Metabolically Healthy Obesity in Patients Seeking Bariatric Surgery: A Cohort Study

BACKGROUND

Bariatric surgery is an effective treatment for morbid obesity. However, a subset of individuals seeking bariatric surgery may exhibit a metabolically healthy obesity (MHO) phenotype, suggesting that they may not experience metabolic complications despite being overweight.

OBJECTIVE

This study aimed to determine the prevalence and metabolic features of MHO in a population undergoing bariatric surgery.

METHODS

A representative sample of 665 participants aged 14 or older who underwent bariatric surgery at our center from January 1, 2010 to January 1, 2020 was included in this cohort study. MHO was defined based on specific criteria, including blood pressure, waist-to-hip ratio, and absence of diabetes.

RESULTS

Among the 665 participants, 80 individuals (12.0%) met the criteria for MHO. Female gender (P = .021) and younger age (P < .001) were associated with a higher likelihood of MHO. Smaller weight and BMI were observed in individuals with MHO. However, a considerable proportion of those with MHO exhibited other metabolic abnormalities, such as fatty liver (68.6%), hyperuricemia (55.3%), elevated lipid levels (58.7%), and abnormal lipoprotein levels (88%).

CONCLUSION

Approximately 1 in 8 individuals referred for bariatric surgery displayed the phenotype of MHO. Despite being metabolically healthy based on certain criteria, a significant proportion of individuals with MHO still exhibited metabolic abnormalities, such as fatty liver, hyperuricemia, elevated lipid levels, and abnormal lipoprotein levels, highlighting the importance of thorough metabolic evaluation in this population.

Effect of an Asian-adapted Mediterranean diet and pentadecanoic acid on fatty liver disease: the TANGO randomized controlled trial

BACKGROUND

Weight loss is the most effective treatment for nonalcoholic fatty liver disease (NAFLD). There is evidence that the Mediterranean diets rich in unsaturated fatty acids and fiber have beneficial effects on weight homeostasis and metabolic risk factors in individuals with NAFLD. Studies have also shown that higher circulating concentrations of pentadecanoic acid (C15:0) are associated with a lower risk for NAFLD.

OBJECTIVES

To examine the effects of a Mediterranean-like, culturally contextualized Asian diet rich in fiber and unsaturated fatty acids, with or without C15:0 supplementation, in Chinese females with NAFLD.

METHODS

In a double-blinded, parallel-design, randomized controlled trial, 88 Chinese females with NAFLD were randomly assigned to 1 of the 3 groups for 12 wk: diet with C15:0 supplementation (n = 31), diet without C15:0 supplementation (n = 28), or control (habitual diet and no C15:0 supplementation, n = 29). At baseline and after the intervention, body fat percentage, intrahepatic lipid content, muscle and abdominal fat, liver enzymes, cardiometabolic risk factors, and gut microbiome were assessed.

RESULTS

In the intention-to-treat analysis, weight reductions of 4.0 ± 0.5 kg (5.3%), 3.4 ± 0.5 kg (4.5%), and 1.5 ± 0.5 kg (2.1%) were achieved in the diet-with-C15:0, diet without-C15:0, and the control groups, respectively. The proton density fat fraction (PDFF) of the liver decreased by 33%, 30%, and 10%, respectively. Both diet groups achieved significantly greater reductions in body weight, liver PDFF, total cholesterol, gamma-glutamyl transferase, and triglyceride concentrations compared with the control group. C15:0 supplementation reduced LDL-cholesterol further, and increased the abundance of Bifidobacterium adolescentis. Fat mass, visceral adipose tissue, subcutaneous abdominal adipose tissue (deep and superficial), insulin, glycated hemoglobin, and blood pressure decreased significantly in all groups, in parallel with weight loss.

CONCLUSION

Mild weight loss induced by a Mediterranean-like diet adapted for Asians has multiple beneficial health effects in females with NAFLD. C15:0 supplementation lowers LDL-cholesterol and may cause beneficial shifts in the gut microbiome.

TRIAL REGISTRATION NUMBER

This trial was registered at the clinicaltrials.gov as NCT05259475.

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.

Divergence in aerobic capacity influences hepatic and systemic metabolic adaptations to bile acid sequestrant and short-term high-fat/sucrose feeding in rats

High versus low aerobic capacity significantly impacts the risk for metabolic diseases. Rats selectively bred for high or low intrinsic aerobic capacity differently modify hepatic bile acid metabolism in response to high-fat diets (HFDs). Here we tested if a bile acid sequestrant would alter hepatic and whole body metabolism differently in rats with high and low aerobic capacity fed a 1-wk HFD. Male rats (8 mo of age) that were artificially selected to be high (HCR) and low-capacity runners (LCR) with divergent intrinsic aerobic capacities were transitioned from a low-fat diet (LFD, 10% fat) to an HFD (45% fat) with or without a bile acid sequestrant (BA-Seq, 2% cholestyramine resin) for 7 days while maintained in an indirect calorimetry system. HFD + BA-Seq increased fecal excretion of lipids and bile acids and prevented weight and fat mass gain in both strains. Interestingly, HCR rats had increased adaptability to enhance fecal bile acid and lipid loss, resulting in more significant energy loss than their LCR counterpart. In addition, BA-Seq induced a greater expression of hepatic CYP7A1 gene expression, the rate-limiting enzyme of bile acid synthesis in HCR rats both on HFD and HFD + BA-Seq diets. HCR displayed a more significant reduction of RQ in response to HFD than LCR, but HFD + BA-Seq lowered RQ in both groups compared with HFD alone, demonstrating a pronounced impact on metabolic flexibility. In conclusion, BA-Seq provides uniform metabolic benefits for metabolic flexibility and adiposity, but rats with higher aerobic capacity display adaptability for hepatic bile acid metabolism.NEW & NOTEWORTHY The administration of bile acid sequestrant (BA-Seq) has uniform metabolic benefits in terms of metabolic flexibility and adiposity in rats with high and low aerobic capacity. However, rats with higher aerobic capacity demonstrate greater adaptability in hepatic bile acid metabolism, resulting in increased fecal bile acid and lipid loss, as well as enhanced fecal energy loss.

Clinical Classification of Obesity and Implications for Metabolic Dysfunction-Associated Fatty Liver Disease and Treatment

Obesity,and metabolic dysfunction-associated fatty liver disease (MAFLD) have reached epidemic proportions globally. Obesity and MAFLD frequently coexist and act synergistically to increase the risk of adverse clinical outcomes (both hepatic and extrahepatic). Type 2 diabetes mellitus (T2DM) is the most important risk factor for rapid progression of steatohepatitis and advanced fibrosis. Conversely, the later stages of MAFLD are associated with an increased risk of T2DM incident. According to the proposed criteria, MAFLD is diagnosed in patients with liver steatosis and in at least one in three: overweight or obese, T2DM, or signs of metabolic dysregulation if they are of normal weight. However, the clinical classification and correlation between obesity and MAFLD is more complex than expected. In addition, treatment for obesity and MAFLD are associated with a reduced risk of T2DM, suggesting that liver-based treatments could reduce the risk of developing T2DM. This review describes the clinical classification of obesity and MAFLD, discusses the clinical features of various types of obesity and MAFLD, emphasizes the role of visceral obesity and insulin resistance (IR) in the development of MAFLD,and summarizes the existing treatments for obesity and MAFLD that reduce the risk of developing T2DM.

Associations of Skeletal Muscle Mass, Muscle Fat Infiltration, Mitochondrial Energetics, and Cardiorespiratory Fitness with Liver Fat Among Older Adults

Background

Muscle mass loss may be associated with liver fat accumulation, yet scientific consensus is lacking and evidence in older adults is scant. It is unclear which muscle characteristics might contribute to this association in older adults.

Methods

We associated comprehensive muscle-related phenotypes including muscle mass normalized to body weight (D 3 -creatine dilution), muscle fat infiltration (MRI), carbohydrate-supported muscle mitochondrial maximal oxidative phosphorylation (respirometry), and cardiorespiratory fitness (VO 2 peak) with liver fat among older adults. Linear regression models adjusted for age, gender, technician (respirometry only), daily minutes of moderate to vigorous physical activity, and prediabetes/diabetes status tested main effects and interactions of each independent variable with waist circumference (high: women-≥88 cm, men-≥102 cm) and gender.

Results

Among older adults aged 75 (IQR 73, 79 years; 59.8% women), muscle mass and liver fat were not associated overall but were positively associated among participants with a high waist circumference (β: 25.2; 95%CI 11.7, 40.4; p =.0002; N=362). Muscle fat infiltration and liver fat were positively associated (β: 15.2; 95%CI 6.8, 24.3; p =.0003; N=378). Carbohydrate-supported maximum oxidative phosphorylation and VO 2 peak (adjusted β: -12.9; 95%CI -20.3, -4.8; p =0.003; N=361) were inversely associated with liver fat; adjustment attenuated the estimate for maximum oxidative phosphorylation although the point estimate remained negative (β: -4.0; 95%CI -11.6, 4.2; p =0.32; N=321).

Conclusions

Skeletal muscle-related characteristics are metabolically relevant factors linked to liver fat in older adults. Future research should confirm our results to determine whether trials targeting mechanisms common to liver and muscle fat accumulation are warranted.

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.

Metabolic Syndrome and Its Association with Nonalcoholic Steatohepatitis

The relationship between insulin resistance, metabolic syndrome (MetS), and nonalcoholic fatty liver disease (NAFLD) is complicated. Although insulin resistance is almost universal in people with NAFLD and MetS, NAFLD may be present without features of MetS and vice versa. While NAFLD has a strong correlation with cardiometabolic risk factors, these are not intrinsic components of this condition. Taken together, our knowledge gaps call for caution regarding the common assertion that NAFLD is the hepatic manifestation of the MetS, and for defining NAFLD in broad terms as a "metabolic dysfunction" based on a diverse and poorly understood constellation of cardiometabolic features.

Impact of Sex and Gender on Clinical Management of Patients with Advanced Chronic Liver Disease and Type 2 Diabetes

Gender differences in the epidemiology, pathophysiological mechanisms and clinical features in chronic liver diseases that may be associated with type 2 diabetes (T2D) have been increasingly reported in recent years. This sexual dimorphism is due to a complex interaction between sex- and gender-related factors, including biological, hormonal, psychological and socio-cultural variables. However, the impact of sex and gender on the management of T2D subjects with liver disease is still unclear. In this regard, sex-related differences deserve careful consideration in pharmacology, aimed at improving drug safety and optimising medical therapy, both in men and women with T2D; moreover, low adherence to and persistence of long-term drug treatment is more common among women. A better understanding of sex- and gender-related differences in this field would provide an opportunity for a tailored diagnostic and therapeutic approach to the management of T2D subjects with chronic liver disease. In this narrative review, we summarized available data on sex- and gender-related differences in chronic liver disease, including metabolic, autoimmune, alcoholic and virus-related forms and their potential evolution towards cirrhosis and/or hepatocarcinoma in T2D subjects, to support their appropriate and personalized clinical management.

Effect of alternate day fasting combined with aerobic exercise on non-alcoholic fatty liver disease: A randomized controlled trial

Innovative non-pharmacological lifestyle strategies to treat non-alcoholic fatty liver disease (NAFLD) are critically needed. This study compared the effects of alternate day fasting (ADF) combined with exercise to fasting alone, or exercise alone, on intrahepatic triglyceride (IHTG) content. Adults with obesity and NAFLD (n = 80, 81% female, age: 23-65 years) were randomized to 1 of 4 groups for 3 months: combination of ADF (600 kcal/2,500 kJ "fast day" alternated with an ad libitum intake "feast day") and moderate-intensity aerobic exercise (5 session per week, 60 min/session); ADF alone; exercise alone; or a no-intervention control group. By month 3, IHTG content was significantly reduced in the combination group (-5.48%; 95% CI, -7.77% to -3.18%), compared with the exercise group (-1.30%; 95% CI, -3.80% to 1.20%; p = 0.02) and the control group (-0.17%; 95% CI, -2.17% to 1.83%; p < 0.01) but was not significantly different versus the ADF group (-2.25%; 95% CI, -4.46% to -0.04%; p = 0.05). Body weight, fat mass, waist circumference, and alanine transaminase (ALT) levels significantly decreased, while insulin sensitivity significantly increased in the combination group compared with the control group. Lean mass, aspartate transaminase (AST), HbA1c, blood pressure, plasma lipids, liver fibrosis score, and hepatokines (fetuin-A, FGF-21, and selenoprotein P) did not differ between groups. Combining intermittent fasting with exercise is effective for reducing hepatic steatosis in patients with NAFLD but may offer no additional benefit versus fasting alone.

The impact of fatigue on mortality of patients with non-alcoholic fatty liver disease: Data from National Health and nutrition examination survey 2005-2010 and 2017-2018

OBJECTIVE

Fatigue among patients with NAFLD may negatively impact their health-related quality of life and clinical outcomes (mortality). We determined fatigue prevalence and its association with all-cause mortality among patients with NAFLD.

DESIGN

NHANES 2005-2010 and 2017-2018 data were used with linked mortality data. NAFLD was defined by fatty liver index for NHANES 2005-2010 and by transient elastography for NHANES 2017-2018. Fatigue was assessed by Patient Health Questionnaire.

RESULTS

NHANES 2005-2010 cohort (n = 5429, mean age 47.1 years, 49.7% male, 69.9% white), 37.6% had NAFLD. Compared to non-NAFLD controls, fatigue was more common in NAFLD (8.35% vs 6.0%, p = .002). Among NHANES 2017-2018 cohort (n = 3830, mean age 48.3 years, 48.6% male, 62.3% white), 36.9% had NAFLD. Compared to non-NAFLD controls, fatigue was more common among NAFLD (8.7% vs 6.2%). NAFLD had more sleep disturbance (34.0% vs 26.7%), cardiovascular disease (CVD) (10.7% vs. 6.3%), significant hepatic fibrosis (liver stiffness>8.0 kPa, 17.9% vs 3.5%) and advanced hepatic fibrosis (>13.1 kPa, 5.4% vs 0.9%; all p < .003). The presence of depression (OR: 11.52, 95% CI: 4.45-29.80, p < .0001), CVD (OR: 3.41, 95% CI: 1.02-11.34, p = .0462) and sleep disturbance (OR: 2.00, 95% CI: 1.00-3.98, p = .0491) was independently associated with fatigue; good sleep quality (OR: 0.58, 95% CI: 0.35-0.96, p = .0366) had an inverse association. By multivariable Cox model, NAFLD adults with fatigue experienced 2.3-fold higher mortality than NAFLD without fatigue (HR: 2.31, 95% CI: 1.37-3.89, p = .002).

CONCLUSIONS

Fatigue among those with NAFLD is associated with increased risk for mortality and is mainly driven by depression, sleep disturbance and CVD. These findings have important clinical implications.

Investigation of the potential mechanism of the Shugan Xiaozhi decoction for the treatment of nonalcoholic fatty liver disease based on network pharmacology, molecular docking and molecular dynamics simulation

Background

Nonalcoholic fatty liver disease (NAFLD) is a metabolic disease, the incidence of which increases annually. Shugan Xiaozhi (SGXZ) decoction, a composite traditional Chinese medicinal prescription, has been demonstrated to exert a therapeutic effect on NAFLD. In this study, the potential bioactive ingredients and mechanism of SGXZ decoction against NAFLD were explored via network pharmacology, molecular docking, and molecular dynamics simulation.

Methods

Compounds in SGXZ decoction were identified and collected from the literature, and the corresponding targets were predicted through the Similarity Ensemble Approach database. Potential targets related to NAFLD were searched on DisGeNET and GeneCards databases. The compound-target-disease and protein-protein interaction (PPI) networks were constructed to recognize key compounds and targets. Functional enrichment analysis of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) was performed on the targets. Molecular docking was used to further screen the potent active compounds in SGXZ. Finally, molecular dynamics (MD) simulation was applied to verify and validate the binding between the most potent compound and targets.

Results

A total of 31 active compounds and 220 corresponding targets in SGXZ decoction were collected. Moreover, 1,544 targets of NAFLD were obtained, of which 78 targets intersected with the targets of SGXZ decoction. Key compounds and targets were recognized through the compound-target-disease and PPI network. Multiple biological pathways were annotated, including PI3K-Akt, MAPK, insulin resistance, HIF-1, and tryptophan metabolism. Molecular docking showed that gallic acid, chlorogenic acid and isochlorogenic acid A could combine with the key targets. Molecular dynamics simulations suggested that isochlorogenic acid A might potentially bind directly with RELA, IL-6, VEGFA, and MMP9 in the regulation of PI3K-Akt signaling pathway.

Conclusion

This study investigated the active substances and key targets of SGXZ decoction in the regulation of multiple-pathways based on network pharmacology and computational approaches, providing a theoretical basis for further pharmacological research into the potential mechanism of SGXZ in NAFLD.

Impaired Metabolic Health and Low Cardiorespiratory Fitness Independently Associate With Subclinical Atherosclerosis in Obesity

CONTEXT

For a given body mass index (BMI), both impaired metabolic health (MH) and reduced cardiorespiratory fitness (CRF) associate with increased risk of cardiovascular disease (CVD).

OBJECTIVE

It remains unknown whether both risk phenotypes relate to CVD independently of each other, and whether these relationships differ in normal weight, overweight, and obese subjects.

METHODS

Data from 421 participants from the Tübingen Diabetes Family Study, who had measurements of anthropometrics, metabolic parameters, CRF (maximal aerobic capacity [VO2max]) and carotid intima-media thickness (cIMT), an early marker of atherosclerosis, were analyzed. Subjects were divided by BMI and MH status into 6 phenotypes.

RESULTS

In univariate analyses, older age, increased BMI, and a metabolic risk profile correlated positively, while insulin sensitivity and VO2max negatively with cIMT. In multivariable analyses in obese subjects, older age, male sex, lower VO2max (std. ß -0.21, P = 0.002) and impaired MH (std. ß 0.13, P = 0.02) were independent determinants of increased cIMT. After adjustment for age and sex, subjects with metabolically healthy obesity (MHO) had higher cIMT than subjects with metabolically healthy normal weight (MHNW; 0.59 ± 0.009 vs 0.52 ± 0.01 mm; P < 0.05). When VO2max was additionally included in this model, the difference in cIMT between MHO and MHNW groups became statistically nonsignificant (0.58 ± 0.009 vs 0.56 ± 0.02 mm; P > 0.05).

CONCLUSION

These data suggest that impaired MH and low CRF independently determine increased cIMT in obese subjects and that low CRF may explain part of the increased CVD risk observed in MHO compared with MHNW.

Glucocorticosteroids and the Risk of NAFLD in Inflammatory Bowel Disease

Each year, the incidence of nonalcoholic fatty liver (NAFLD) disease increases. NAFLD is a chronic disease. One of the most common causes of NAFLD is an inadequate lifestyle, which is characterized by a lack or low physical activity and eating highly processed foods rich in saturated fat and salt and containing low amount of fiber. Moreover, disturbances in intestinal microbiome and the use of certain drugs may predispose to NAFLD. NAFLD is an increasingly described disease in patients with inflammatory bowel disease (IBD). Recent data also indicate a frequent coexistence of metabolic syndrome in this group of patients. Certain groups of drugs also increase the risk of developing inflammation, liver fibrosis, and cirrhosis. Particularly important in the development of NAFLD are steroids, which are used in the treatment of many diseases, for example, IBD. NAFLD is one of the most frequent parenteral manifestations of the disease in IBD patients. However, there is still insufficient information on what dose and exposure time of selected types of steroids may lead to the development of NAFLD. It is necessary to conduct further research in this direction. Therefore, patients with IBD should be constantly monitored for risk factors for the development of NAFLD.

Comprehensive Review and Updates on Holistic Approach Towards Non-Alcoholic Fatty Liver Disease Management with Cardiovascular Disease

PURPOSE OF REVIEW

The global prevalence of non-alcoholic fatty liver disease (NAFLD) presents an unmet need in treating these, often asymptomatic, individuals. In this review, we summarised NAFLD management and described recent developments in non-alcoholic steatohepatitis (NASH) therapeutics that can shape the future of NAFLD.

RECENT FINDINGS

A multi-disciplinary effort in promoting sustainable lifestyle measures is paramount, with the goal of either limiting energy surplus alone or in combination with targeting downstream pathways of inflammation and fibrosis. Several antidiabetic medications like PPAR-γ agonist and glucagon-like peptide receptor agonists have beneficial effects on the metabolic profile as well as NASH histology. Vitamin E has shown promise in specific groups of patients with the haptoglobin2 allele protein. Newer drugs have demonstrated promising results in NASH resolution and fibrosis improvement such as obeticholic acid, resmetirom, aramchol, efruxifermin, aldafermin and lanifibranor. Apart from discussing the results of late stage clinical trials and the possible challenges in managing these patients with limited approved therapies, we also discussed the specific management of comorbidities (diabetes, hypertension, hyperlipidaemia, cardiovascular diseases) in NAFLD patients. Treatment strategy needs to target improvements in liver-related outcomes and cardiometabolic profile.

Malaysian Society of Gastroenterology and Hepatology consensus statement on metabolic dysfunction-associated fatty liver disease

The Malaysian Society of Gastroenterology and Hepatology saw the need for a consensus statement on metabolic dysfunction-associated fatty liver disease (MAFLD). The consensus panel consisted of experts in the field of gastroenterology/hepatology, endocrinology, bariatric surgery, family medicine, and public health. A modified Delphi process was used to prepare the consensus statements. The panel recognized the high and increasing prevalence of the disease and the consequent anticipated increase in liver-related complications and mortality. Cardiovascular disease is the leading cause of mortality in MAFLD patients; therefore, cardiovascular disease risk assessment and management is important. A simple and clear liver assessment and referral pathway was agreed upon, so that patients with more severe MAFLD can be linked to gastroenterology/hepatology care, while patients with less severe MAFLD can remain in primary care or endocrinology, where they are best managed. Lifestyle intervention is the cornerstone in the management of MAFLD. The panel provided a consensus on the use of statin, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker, sodium-glucose cotransporter-2 inhibitor, glucagon-like peptide-1 agonist, pioglitazone, vitamin E, and metformin, as well as recommendations on bariatric surgery, screening for gastroesophageal varices and hepatocellular carcinoma, and liver transplantation in MAFLD patients. Increasing the awareness and knowledge of the various stakeholders on MAFLD and incorporating MAFLD into existing noncommunicable disease-related programs and activities are important steps to tackle the disease. These consensus statements will serve as a guide on MAFLD for clinicians and other stakeholders.

Overweight, Obesity, and CVD Risk: a Focus on Visceral/Ectopic Fat

PURPOSE OF REVIEW

Despite its prevalence and well-documented impact on population health, obesity has not emerged as a strong independent risk factor for cardiovascular disease after control for intermediate risk factors. The purpose of this brief narrative review is to highlight results from imaging studies that have not only documented the remarkable heterogeneity of body fat topography but also the importance of visceral adiposity as a key body fat depot associated with cardiovascular disease risk and type 2 diabetes.

RECENT FINDINGS

Simple tools are also discussed in order to refine cardiometabolic risk assessment in persons with overweight/obesity. It is proposed that four lifestyle vital signs should be considered in clinical practice to improve discrimination of health risk in individuals with overweight/obesity: waist circumference as a simple marker of abdominal adiposity, cardiorespiratory fitness, overall diet quality, and level of reported physical activity. Heterogeneity of obesity is proposed as an example of a condition that would benefit from a precision lifestyle medicine approach.

U-DECIDE: Utilising technology for Diet & Exercise Change In complex chronic conditions across Diverse Environments: Protocol for a Randomised Controlled Trial (Preprint)

Background

The metabolic syndrome is common across many complex chronic disease groups. Advances in health technology have provided opportunities to support lifestyle interventions.

Objective

The purpose of this study is to test the feasibility of a health technology-assisted lifestyle intervention in a patient-led model of care.

Methods

The study is a single-center, 26-week, randomized controlled trial. The setting is specialist kidney and liver disease clinics at a large Australian tertiary hospital. The participants will be adults with a complex chronic condition who are referred for dietetic assessment and display at least one feature of the metabolic syndrome. All participants will receive an individualized assessment and advice on diet quality from a dietitian, a wearable activity monitor, and standard care. Participants randomized to the intervention group will receive access to a suite of health technologies from which to choose, including common base components (text messages) and optional components (online and mobile app–based nutrition information, an online home exercise program, and group-based videoconferencing). Exposure to the optional aspects of the intervention will be patient-led, with participants choosing their preferred level of engagement. The primary outcome will be the feasibility of delivering the program, determined by safety, recruitment rate, retention, exposure uptake, and telehealth adherence. Secondary outcomes will be clinical effectiveness, patient-led goal attainment, treatment fidelity, exposure demand, and participant perceptions. Primary outcome data will be assessed descriptively and secondary outcomes will be assessed using an analysis of covariance. This study will provide evidence on the feasibility of the intervention in a tertiary setting for patients with complex chronic disease exhibiting features of the metabolic syndrome.

Results

The study was funded in 2019. Enrollment has commenced and is expected to be completed by June 2022. Data collection and follow up are expected to be completed by December 2022. Results from the analyses based on primary outcomes are expected to be submitted for publication by June 2023.

Conclusions

The study will test the implementation of a health technology–assisted lifestyle intervention in a tertiary outpatient setting for a diverse group of patients with complex chronic conditions. It is novel in that it embeds patient choice into intervention exposure and will inform health service decision-makers in regards to the feasibility of scale and spread of technology-assisted access to care for a broader reach of specialist services.

Trial Registration

Australian New Zealand Clinical Trial Registry ACTRN12620001282976; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=378337

International Registered Report Identifier (IRRID)

DERR1-10.2196/37556

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.

Adherence to lifestyle modification in patients with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) makes a major impact on morbidity and mortality among the workingage population in developed countries. In the lack of effective pharmacological methods, the leading role in treatment of NAFLD belongs to lifestyle modification, consistent and gradual weight loss, and its maintenance. The qualitative and quantitative structure of the diet, intensity of physical activity, and most importantly, regularity and consistency of implementation of lifestyle modification activities are the key to successful management of patients with NAFLD.

To date, there are very few studies on adherence to lifestyle modification activities in this group of patients, which is mainly due to a deficiency of methodological tools. The questionnaire “QAA-25” recommended by the Russian Scientific Medical Society of Therapists for quantitative assessment of adherence to treatment allows to assess both adherence to therapy in general and adherence to its individual components (adherence to drug therapy, adherence to medical counseling, and adherence to lifestyle modification), which requires further study taking into account features of therapeutic strategies in treating 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.

Non-alcoholic fatty liver disease in obese children and adolescents: a role for nutrition?

Non-alcoholic fatty liver disease (NAFLD) has become the most common cause of chronic liver disease in children, paralleling the increasing prevalence of obesity worldwide. The pathogenesis of paediatric NAFLD is not fully understood, but it is known that obesity, nutrition, lifestyle variables, genetic and epigenetic factors may be causally involved in the development of this common metabolic liver disease. In particular, obesity and nutrition are among the strongest risk factors for paediatric NAFLD, which may exert their adverse hepatic effects already before birth. Excess energy intake induces hypertrophy and hyperplasia of adipose tissue with subsequent development of systemic insulin resistance, which is another important risk factor for NAFLD. Diet composition and in particular simple carbohydrate intake (especially high fructose intake) may promote the development of NAFLD, whereas non-digestible carbohydrates (dietary fiber), by affecting gut microbiota, may favour the integrity of gut wall and reduce inflammation, opposing this process. Saturated fat intake may also promote NAFLD development, whereas unsaturated fat intake has some beneficial effects. Protein intake does not seem to affect the development of NAFLD, but further investigation is needed. In conclusion, lifestyle modifications to induce weight loss, through diet and physical activity, remain the mainstay of treatment for paediatric NAFLD. The use of dietary supplements, such as omega-3 fatty acids and probiotics, needs further study before recommendation.

Metabolomics and lipidomics in NAFLD: biomarkers and non-invasive diagnostic tests

Nonalcoholic fatty liver disease (NAFLD) is one of the most common liver diseases worldwide and is often associated with aspects of metabolic syndrome. Despite its prevalence and the importance of early diagnosis, there is a lack of robustly validated biomarkers for diagnosis, prognosis and monitoring of disease progression in response to a given treatment. In this Review, we provide an overview of the contribution of metabolomics and lipidomics in clinical studies to identify biomarkers associated with NAFLD and nonalcoholic steatohepatitis (NASH). In addition, we highlight the key metabolic pathways in NAFLD and NASH that have been identified by metabolomics and lipidomics approaches and could potentially be used as biomarkers for non-invasive diagnostic tests. Overall, the studies demonstrated alterations in amino acid metabolism and several aspects of lipid metabolism including circulating fatty acids, triglycerides, phospholipids and bile acids. Although we report several studies that identified potential biomarkers, few have been validated.

Effect of vanillic acid and exercise training on fatty liver and insulin resistance in rats: Possible role of fibroblast growth factor 21 and autophagy

BACKGROUND AND AIMS

The prevalence of non-alcoholic fatty liver disease has been alarmingly increased with no lines of effective treatment. Vanillic acid is a naturally occurring polyphenol with promising therapeutic effects. Exercise is well known to be an effective tool against obesity and its consequences. Thus, we aim to study the effect of vanillic acid alone and along with exercise on fatty liver induced by a high-fat diet in a rat model and to investigate possible novel mechanisms involved in their action.

METHODS

In this study, 40 male rats were divided equally into five groups: control (standard chow diet), HFD (high-fat diet), HFD+VA (HFD+ vanillic acid (50 mg/kg/day orally), HFD+EX (HFD+ swimming exercise 5 days/week), HFD+VA+EX (HFD+ vanillic acid+ swimming exercise) for eight weeks.

RESULTS

Body mass, liver weight, liver enzymes, cholesterol, and triglycerides were significantly decreased in the combined VA+EX group, with marked improvement in hyperglycemia, hyperinsulinemia, and consequently HOMA-IR index compared to the HFD group. These improvements were also reflected in the pathological view. VA and swimming, either solely or in combination, markedly increased hepatic and circulating fibroblast growth factor 21. Additionally, VA and swimming increased the immunohistochemical expression of the autophagosomal marker LC3 and decreased the expression of P62, which is selectively degraded during autophagy.

CONCLUSIONS

These results suggest the hepatoprotective effect of VA and swimming exercise against fatty liver and the involvement of FGF21 and autophagy in their effect.

Physical activity is associated with reduced risk of liver disease in the prospective UK Biobank cohort

BACKGROUND & AIMS

Previous studies have identified physical activity as an important lifestyle factor in the pathogenesis of chronic liver diseases (CLD). However, most studies were short in follow-up, and based on self-reported activity. Moreover, it is unknown whether physical activity affects the risk of liver disease development in the general population. Herein, we aimed to clarify the association between physical activity and CLD by examining the risk of liver disease and progression in relation to accelerometer-based physical activity in a large subset of prospectively recruited participants in the UK Biobank.

METHODS

We analysed data from 96,688 participants that recorded their physical activity through the use of a wrist accelerometer. Relative risks for development of liver diseases were calculated using multivariable-adjusted Cox regression models. In a subgroup of participants without any previously diagnosed liver disease (n = 95,974), a total of 374 liver disease cases were diagnosed during follow-up (mean = 5.5 years).

RESULTS

Participants in the top compared with the bottom quartile of physical activity had a reduced risk of both overall CLD (hazard ratio [HR]: 0.41 [0.29-0.59]) and NAFLD (HR: 0.39 [0.21-0.70]). An activity increase of an additional 2,500 steps per day, was associated with a 38% reduction in CLD and a 47% reduction in NAFLD development, independent of adiposity. In the subgroup of participants with previously diagnosed liver disease (n = 714), participants in the top compared with the bottom quartile of physical activity had a striking 89% risk reduction in liver-related death (HR: 0.11 [0.02-0.86]), and 85% risk reduction in all-cause mortality (adjusted HR: 0.15 [0.05-0.44]). Walking an additional 2,500 steps per day was associated with 44% reduction in liver disease progression.

CONCLUSIONS

Greater physical activity is associated with a dose-dependent reduction in liver disease, which appears to be independent of adiposity.

LAY SUMMARY

In this study, we aimed to clarify the association between accelerometer-measured physical activity and chronic liver disease by examining risk of overall and specific liver diseases and their progression in relation to accelerometer-based physical activity in 96,688 participants in the UK Biobank. Our results show a clear, dose-dependent protective association between accelerometer-measured physical activity and liver disease development and progression. The linkage of device-measured activity could therefore create a framework for using wearables for personalised prevention of liver diseases.

The association between cardiorespiratory fitness, liver fat and insulin resistance in adults with or without type 2 diabetes: a cross-sectional analysis

Background

Exercise-induced improvements in cardiorespiratory fitness (CRF) often coincide with improvements in insulin sensitivity and reductions in liver fat content. However, there are limited data concerning the relationship between CRF and liver fat content in adults with varying degrees of metabolic dysfunction.

Methods

The aim of this study was to examine the association between CRF, liver fat content, and insulin resistance in inactive adults with obesity and with or without type 2 diabetes (T2D), via cross-sectional analysis. CRF was determined via a graded exercise test. Liver fat content was assessed via proton magnetic resonance spectroscopy and insulin resistance was assessed via homeostatic model of insulin resistance (HOMA-IR). A partial correlation analysis, controlling for age and gender, was performed to determine the association between CRF, demographic, cardiometabolic, and anthropometric variables. Independent t tests were performed to compare cardiometabolic outcomes between participants with T2D and participants without T2D.

Results

Seventy-two adults (46% male) with a mean age of 49.28 ± 10.8 years, BMI of 34.69 ± 4.87 kg/m², liver fat content of 8.37 ± 6.90%, HOMA-IR of 3.07 ± 2.33 and CRF of 21.52 ± 3.77 mL/kg/min participated in this study. CRF was inversely associated with liver fat content (r = − 0.28, p = 0.019) and HOMA-IR (r = − 0.40, p < 0.001). Participants with T2D had significantly higher liver fat content (+ 3.66%, p = 0.024) and HOMA-IR (+ 2.44, p < 0.001) than participants without T2D. Participants with T2D tended to have lower CRF than participants without T2D (− 1.5 ml/kg/min, p = 0.094).

Conclusion

CRF was inversely associated with liver fat content and insulin resistance. Participants with T2D had lower CRF than those without T2D, however, the difference was not statistically significant. Further longitudinal studies are required to elucidate the relationship between CRF and the progression of obesity-related diseases such as T2D.

Registration: ACTRN12614001220651 (retrospectively registered on the 19th November 2014) and ACTRN12614000723684 (prospectively registered on the 8th July 2014).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13102-021-00261-9.

Effect of Aerobic Exercise Intensity on Energy Expenditure and Weight Loss in Severe Obesity-A Randomized Controlled Trial

OBJECTIVE

This study aimed to compare the effects of two aerobic exercise programs of different intensities on energy expenditure.

METHODS

This was a single-center randomized controlled trial of patients with severe obesity allocated to a 24-week moderate-intensity continuous training (MICT) program or a combined MICT with high-intensity interval training (HIIT/MICT) program. The primary outcome was energy expenditure during exercise (EEDE). Secondary outcomes included resting metabolic rate, cardiorespiratory fitness, and body composition.

RESULTS

A total of 82 (56% females) patients were screened, and 71 (55% females) patients were allocated to HIIT/MICT (n = 37) or MICT (n = 34). Per-protocol analysis showed that EEDE increased by 10% (95% CI: 3%-17%) in the HIIT/MICT group (n = 16) and 7.5% (95% CI: 4%-10%) in the MICT group (n = 24), with no differences between groups. In the 8- to 16- week per-protocol analysis, the HIIT/MICT group had a significantly larger increase in EEDE compared with the MICT group. Resting metabolic rate remained unchanged in both groups. HIIT/MICT and MICT were associated with significant weight loss of 5 kg and 2 kg, respectively.

CONCLUSIONS

Patients completing a 24-week combined HIIT/MICT program did not achieve a higher EEDE compared with those who completed a 24-week MICT program. The HIIT/MICT group experienced, on average, a 3-kg-larger weight loss than the MICT group.

Detection and Characterization of Phosphorylation, Glycosylation, and Fatty Acid Bound to Fetuin A in Human Blood

The hepatokine fetuin A (Fet A) has been associated with diverse pathological states such as insulin resistance, type 2 diabetes, macrovascular disease, and systemic ectopic and vascular calcification. Fet A may also play a role in tumor growth and metastasis. The biological activity of Fet A may be affected by various modifications, including phosphorylation, O- and N-glycosylation and fatty acid binding. We developed an antibody-based assay for the detection of Fet A phosphorylated at serine 312. Fatty acid pattern was determined by gas chromatography. Using the antibody, we found that the phosphorylation was stable in human plasma or serum at room temperature for 8 h. We observed that Fet A is present in several glycosylation forms in human plasma, but the extent of Ser³¹² phosphorylation was not associated with glycosylation. The phosphorylation pattern did not change during an oral glucose tolerance test (0–120 min). We further found that human Fet A binds preferentially saturated fatty acids (>90%) at the expense of mono- and poly-unsaturated fatty acids. Our results indicate that different molecular species of Fet A are present in human plasma and that these different modifications may determine the different biological effects of Fet A.

Aerobic Exercise in the Management of Metabolic Dysfunction Associated Fatty Liver Disease

Sedentarism is the pandemic of modern times. It is associated with several medical conditions including obesity, type 2 diabetes mellitus, cardiovascular diseases and also liver disease, particularly metabolic dysfunction associated fatty liver disease (MAFLD). In an era when MAFLD is the most prevalent chronic liver disease worldwide, whilst no pharmacological therapy has been approved for it, exercise has proved to be effective in improving liver steatosis. Interestingly, exercise decreases liver fat even in the absence of weight loss. The challenge for the clinician is to motivate the obese patient with MAFLD, and associated co-morbidities, who has crystallized a sedentary behavior, at times when every need is at the distance of a click on the Internet, and the entire world can be visited behind a screen. In this review, the aggregate evidence on the mechanisms and effects of exercise in the management of MAFLD is summarized, with simple recommendations for everyday clinical practice.

The Gut Barrier, Intestinal Microbiota, and Liver Disease: Molecular Mechanisms and Strategies to Manage

Liver disease encompasses pathologies as non-alcoholic fatty liver disease, non-alcoholic steatohepatitis, alcohol liver disease, hepatocellular carcinoma, viral hepatitis, and autoimmune hepatitis. Nowadays, underlying mechanisms associating gut permeability and liver disease development are not well understood, although evidence points to the involvement of intestinal microbiota and their metabolites. Animal studies have shown alterations in Toll-like receptor signaling related to the leaky gut syndrome by the action of bacterial lipopolysaccharide. In humans, modifications of the intestinal microbiota in intestinal permeability have also been related to liver disease. Some of these changes were observed in bacterial species belonging Roseburia, Streptococcus, and Rothia. Currently, numerous strategies to treat liver disease are being assessed. This review summarizes and discusses studies addressed to determine mechanisms associated with the microbiota able to alter the intestinal barrier complementing the progress and advancement of liver disease, as well as the main strategies under development to manage these pathologies. We highlight those approaches that have shown improvement in intestinal microbiota and barrier function, namely lifestyle changes (diet and physical activity) and probiotics intervention. Nevertheless, knowledge about how such modifications are beneficial is still limited and specific mechanisms involved are not clear. Thus, further in-vitro, animal, and human studies are needed.

Improvement in histological endpoints of MAFLD following a 12-week aerobic exercise intervention

BACKGROUND

Lifestyle interventions are the primary treatment for metabolic (dysfunction) associated fatty liver disease (MAFLD). However, the histological and cardiometabolic effects of aerobic exercise in MAFLD remain unclear.

AIMS

To assess the effects of a 12-week aerobic exercise intervention on histological and cardiometabolic endpoints in MAFLD.

METHODS

Patients with biopsy-confirmed MAFLD participated in a 12-week aerobic exercise intervention. Liver histology, cardiorespiratory fitness (estimated V̇O_2max ), physical activity, anthropometry and biochemical markers were assessed at baseline, intervention completion, and 12 and 52 weeks after intervention completion.

RESULTS

Twenty-four patients completed the exercise intervention (exercise group n = 16, control group n = 8). In the exercise group, 12 weeks of aerobic exercise reduced fibrosis and hepatocyte ballooning by one stage in 58% (P = 0.034) and 67% (P = 0.020) of patients, with no changes in steatosis (P = 1.000), lobular inflammation (P = 0.739) or NAFLD activity score (P = 0.172). Estimated V̇O_2max increased by 17% compared to the control group (P = 0.027) but this level of improvement was not maintained at 12 or 52 weeks after the intervention. Patients with fibrosis and ballooning improvement increased estimated V̇O_2max by 25% (P = 0.020) and 26% (P = 0.010), respectively. Anthropometric reductions including body mass (P = 0.038), waist circumference (P = 0.015) and fat mass (P = 0.007) were also observed, but no patient achieved 7%-10% weight loss.

CONCLUSION

This study highlights the potential benefits of a 12-week aerobic exercise intervention in improving histological endpoints of MAFLD. The development of strategies to ensure continued engagement in aerobic exercise in MAFLD are needed.

Role of intensive dietary and lifestyle interventions in the treatment of lean nonalcoholic fatty liver disease patients

BACKGROUND/AIM

Although weight loss is recommended for the treatment of nonalcoholic fatty liver disease (NAFLD) in overweight and obese individuals, this treatment modality remains questionable in lean individuals. In this study, we investigated the effects of medical nutrition therapy (MNT) and intensive lifestyle interventions (ILIs) for NAFLD in lean versus obese patients.

METHODS

In total, 35 patients (14 lean and 21 obese) were included in the study. All patients underwent transient elastography examinations, and controlled attenuation parameter (CAP) of >238 dB/m was indicative of hepatic steatosis. After 8 weeks of dietitian follow-up with MNT and ILI, the patients were compared with the baseline.

RESULTS

Significant weight loss was recorded in both lean (5.4%) and obese patients (5.7%) with NAFLD. The mean BMI decreased from 23.9 (20.5-24.8) to 22.4 (19.5-24.2) kg/m (P = 0.001) in lean patients and from 34.0 (30.0-42.0) to 31.6 (26.9-42.5) kg/m (P < 0.001) in obese patients. The alanine aminotransferase level significantly decreased from 56 (15-163) to 28 (13-98) U/L (P = 0.010) in lean patients and from 27 (13-81) to 22 (13-46) U/L (P = 0.018) in obese patients. The median CAP decreased from 299 (246-360) to 236 (169-318) dB/m (P = 0.002) in lean patients and from 325 (258-400) to 253 (202-383) dB/m (P < 0.001) in obese patients. Moreover, remission of hepatic steatosis was detected in eight lean patients (57.1%) and eight obese patients (38.1%).

CONCLUSION

These results indicate that 5% body weight loss in effective in both obese and lean patients resulting in a similar NAFLD remission.

Cross-sectional analysis of the health profile and dietary intake of a sample of Canadian adults diagnosed with non-alcoholic fatty liver disease

Background

Dietary intake is an important factor in the development and management of non-alcoholic fatty liver disease (NAFLD); however, optimal dietary composition remains unclear. Moreover, there is minimal evidence on the relationship between dietary intake and markers of liver health in Canadian adults diagnosed with NAFLD.

Objective

The aim of this study is to characterize the dietary intake of a sample of Canadian adults diagnosed with NAFLD and examine the correlations with markers of liver health.

Design

Forty-two adults recruited from the community and hepatology clinics in Calgary, Canada from 2016 to 2019 completed a 3-day food record. Anthropometrics, blood biomarkers, liver stiffness (FibroScan), and liver fat (magnetic resonance imaging) were measured. Nutrient intake was compared with the data from the 2004 and 2015 Canadian Community Health Surveys. Relationships were assessed using Pearson’s correlation and regression analysis.

Results

Relative to Canadian dietary recommendations, participants consumed lower magnesium, fiber, calcium, vitamin D, and vitamin E, and higher cholesterol, saturated fat, total fat, fructose, iron, vitamin B12, selenium, phosphorus, and sodium. Compared with the national average, participants consumed more energy, fiber, sodium, total fat, and saturated fat. Systolic blood pressure (P = 0.012), serum α-2 macroglobulin (P = 0.008), carbohydrate (P = 0.022), total fat (P = 0.029), and saturated fat intakes (P = 0.029) were associated with FibroScan scores. Liver fat was correlated with serum triglycerides (P < 0.001), trunk fat (P = 0.029), added sugar (P = 0.042), phosphorus (P = 0.017), and magnesium intake (P = 0.013). In females, selenium intake was associated with liver fat (P = 0.015) and FibroScan score (P = 0.05), while in males, liver fat was associated with trunk fat (P = 0.004), body weight (P = 0.004), high-density lipoprotein (P < 0.001), and fructose intake (P = 0.037). Regression analysis showed that increasing magnesium intake corresponds to a decrease in liver fat.

Conclusion

Despite the higher energy intake of participants, overall nutrient intake is low, suggesting lower diet quality. Associations between select micronutrients and liver health markers warrant further investigation.

Exercise as Medicine: The Impact of Exercise Training on Nonalcoholic Fatty Liver Disease

Purpose of review

Nonalcoholic fatty liver disease (NAFLD) is a leading cause of global liver disease. Because current pharmacologic treatments are ineffective, lifestyle change centered on exercise remains the most effective NAFLD treatment. The aim of this systematic review is to summarize and evaluate the current evidence supporting the use of exercise training as a medical treatment for adult patients with NAFLD.

Recent findings

At least 150 minutes each week of moderate intensity exercise of any type can improve NAFLD, both with and without modest weight loss. Exercise training reduces hepatic steatosis and liver inflammation, favorably changes body composition, improves vascular endothelial function, increases cardiorespiratory fitness and can lead to histologic response. To date, exercise-based NAFLD trials are limited by small sample size and significant heterogeneity.

Summary

While several key questions remain unanswered, exercise training will always be an important part of the medical management of patients with NAFLD.

Exercise adaptations: molecular mechanisms and potential targets for therapeutic benefit

Exercise is fundamental for good health, whereas physical inactivity underpins many chronic diseases of modern society. It is well appreciated that regular exercise improves metabolism and the metabolic phenotype in a number of tissues. The phenotypic alterations observed in skeletal muscle are partly mediated by transcriptional responses that occur following each individual bout of exercise. This adaptive response increases oxidative capacity and influences the function of myokines and extracellular vesicles that signal to other tissues. Our understanding of the epigenetic and transcriptional mechanisms that mediate the skeletal muscle gene expression response to exercise as well as of their upstream signalling pathways has advanced substantially in the past 10 years. With this knowledge also comes the opportunity to design new therapeutic strategies based on the biology of exercise for a variety of chronic conditions where regular exercise might be a challenge. This Review provides an overview of the beneficial adaptive responses to exercise and details the molecular mechanisms involved. The possibility of designing therapeutic interventions based on these molecular mechanisms is addressed, using relevant examples that have exploited this approach.

Endothelial Dysfunction, a Marker of Atherosclerosis, Is Independent of Metabolic Syndrome in NAFLD Patients

BACKGROUND

The study was designed to assess cardiovascular risk factors flow-mediated dilatation % (FMD%) and carotid intima-media thickness (CIMT) in NAFLD.

METHODS

126 NAFLD subjects and 31 chronic hepatitis B (CHB) controls were studied. Measuring carotid intima-media thickness (CIMT) and the flow-mediated dilatation % (FMD%) by brachial artery Doppler ultrasound were used to assess atherosclerosis. The risk of cardiac events at 10 years (ROCE 10) was estimated by the Prospective Cardiovascular Munster Study (PROCAM) score.

RESULTS

58 of 126 NAFLD have coexistent metabolic syndrome. Mean CIMT was 0.73 ± 0.041 mm among NAFLD with MS, 0.66 ± 0.016 mm among NAFLD without MS, and 0.66 ± 0.037 in controls CHB patients. FMD% in NAFLD with MS was 10.43 ± 3.134%, but was 8.56 ± 3.581% in NAFLD without MS and 17.78 ± 6.051% in controls. PROCAM score of NAFLD with MS was 46.95 ± 6.509 while in NAFLD without MS was 38.2 ± 3.738. Controls had a PROCAM score of 38.13 ± 5.755. ROCE 10 in NAFLD with MS was 13.64 ± 8.568 while NAFLD without MS was 5.55 ± 1.949. Controls have a ROCE 10 of 5.95 ± 3.973. Post hoc analysis showed CIMT was dependent upon MS while FMD% was different between all subgroups hence independent of metabolic syndrome.

CONCLUSION

The markers of endothelial dysfunction are significantly higher in patients with NAFLD than controls.

Epidemiology and pathophysiology of the association between NAFLD and metabolically healthy or metabolically unhealthy obesity

The prevalence of nonalcoholic fatty liver disease (NAFLD) is continuing to rise in many countries, paralleling the epidemic of obesity worldwide. In the last years, the concept of metabolically healthy obesity [MHO, generally defined as obesity without metabolic syndrome (MetS)] has raised considerable scientific interest. MHO is a complex phenotype with risks intermediate between metabolically healthy individuals with normal-weight (NWMH) and patients who are obese and metabolically unhealthy (MUO, i.e. obesity with MetS). In this review we aimed to examine the association and pathophysiological link of NAFLD with MHO and MUO. Compared to NWMH individuals, patients with obesity, regardless of the presence of MetS features, are at higher risk of all-cause mortality and cardiovascular events. Moreover, MHO patients have a greater risk of NAFLD development and progression compared to NWMH individuals. However, this risk is generally lower than that of MUO patients, suggesting a stronger adverse effect of coexisting MetS disorders than obesity per se on the severity of NAFLD. Nevertheless, since MHO is a dynamic state (with a significant proportion of MHO subjects progressing to MUO over time) and NAFLD itself may predict the transition from MHO to MUO, we believe that any effort should be made to identify NAFLD in all obese individuals, although they appear to be "metabolically healthy". Future research is needed to better understand the role of NAFLD and other pathogenic factors potentially involved in the transition from MHO to MUO and to elucidate how this transition may affect the presence and severity of NAFLD.

Physical activity compared to adiposity and risk of liver-related mortality: Results from two prospective, nationwide cohorts

BACKGROUND & AIMS

Obesity in adulthood has been associated with increased risk of liver-related mortality. Whether higher levels of physical activity counteract the excess risk conferred by obesity remains unknown. We simultaneously evaluated the long-term impact of physical activity and adiposity on liver-related mortality, within 2 nationwide populations.

METHODS

We conducted a prospective cohort study of 77,238 women and 48,026 men, with detailed, validated assessments of weekly physical activity (metabolic equivalent task [MET]-hours]), adiposity (body mass index [BMI], waist circumference), and diet, alcohol use and clinical comorbidities, biennially from 1986 through 2012. Using Cox proportional hazards regression models, we calculated multivariable-adjusted hazard ratios (aHRs) and 95% CIs for liver-related mortality, including death from hepatocellular carcinoma (HCC) and other complications of cirrhosis.

RESULTS

Over 1,856,226 person-years, we recorded 295 liver-related deaths (108 HCC; 187 cirrhosis). Risk of liver-related mortality increased monotonically with higher BMI during adulthood (ptrend<0.0001) and with weight gain during early adulthood (ptrend <0.0001). The risk of liver-related mortality also declined progressively, with increasing physical activity (ptrend = 0.0003); the aHRs across increasing physical activity quintiles were: 1.0, 0.70 (95% CI 0.51-0.96), 0.59 (95% CI 0.42-0.84), 0.52 (95% CI 0.36-0.74) and 0.46 (95% CI 0.31-0.66). Compared to lean-active adults (BMI <25; ≥18 MET-hours/week), the aHRs for obese-active, lean-sedentary, and obese-sedentary adults were: 1.04 (95% CI 0.73-1.37), 2.08 (95% CI 1.21-3.33) and 3.40 (95% CI 2.06-5.56), respectively. Findings were similar for HCC-specific and cirrhosis-specific mortality. Overall, engaging in average-pace walking for >3 hours/week could have prevented 25% of liver-related deaths (95% CI 0.12-0.38).

CONCLUSIONS

In 2 prospective, nationwide cohorts, both excess adiposity and reduced physical activity were significant predictors of liver-related mortality. Achieving higher physical activity levels counteracted the excess liver-related risks associated with obesity.

LAY SUMMARY

This is the first large, prospective cohort study to simultaneously evaluate the impact of obesity and physical activity on the long-term risk of liver-related mortality in 2 nationwide populations of American men and women. The study demonstrated that obesity predicted significantly increased risk of liver-related mortality, while physical activity predicted significantly lower risk of liver-related mortality. Importantly, the excess risk of liver-related mortality observed with obesity was no longer statistically significant among adults who engaged in the equivalent of average-pace walking for 3 hours or more, per week.

Decreased Physical Working Capacity in Adolescents With Nonalcoholic Fatty Liver Disease Associates With Reduced Iron Availability

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) is common and related to obesity and insulin resistance. Iron metabolism is impaired in obese individuals and iron deficiency has been associated with physical inactivity. We investigated whether iron bioavailability is reduced in patients with NAFLD and contributes to reduced cardiorespiratory fitness.

METHODS

We collected information on weight-adjusted, submaximal physical work capacity (PWC), ultrasound-determined hepatic steatosis, iron indices, and hematologic and metabolic parameters from 390 female and 458 male participants of the Raine Study-a longitudinal study of disease development in 2868 children in Western Australia. X² and linear regression analyses were used to compare characteristics of study participants according to NAFLD status at age 17 years.

RESULTS

Fourteen percent of the cohort had NAFLD. PWC was significantly reduced in adolescents with NAFLD compared to adolescents without NAFLD (reduction of 0.17 W/kg, P = .0003, adjusted for sex and body mass index [BMI]). Iron bioavailability (assessed by mean corpuscular volume [MCV], mean corpuscular haemoglobin [MCH], transferrin saturation, and serum levels of iron) was inversely correlated with BMI in adolescents with NAFLD (P ≤ .01 for all, adjusted for sex) but not in adolescents without NAFLD (P > .30). MCV and MCH correlated with PWC (MCV, P = .002 for female and P = .0003 male participants; MCH, P = .004 for female and P = .01 for male participants), irrespective of NAFLD status. Reduced PWC was associated with lower transferrin saturation in adolescents with NAFLD (reduction of 0.012 W/kg per unit decrease in transferrin saturation, P = .007) but not in adolescents without NAFLD (reduction of 0.001 W/kg, P = .40), adjusted for sex. This association was independent of MCV or MCH.

CONCLUSIONS

In a well-defined cohort of adolescents, we found NAFLD to be associated with decreased cardiorespiratory fitness, independent of BMI. The relationship between transferrin saturation and PWC in adolescents with NAFLD indicates that functional iron deficiency might contribute to reductions in cardiorespiratory fitness.

Estimated Cardiorespiratory Fitness Attenuates the Impacts of Sarcopenia and Obesity on Non-Alcoholic Fatty Liver in Korean Adults

This population-based, cross-sectional study examined the preventive role of non-exercise-based estimation of cardiorespiratory fitness (eCRF) against the impacts of sarcopenia and obesity on the non-alcoholic fatty liver (NAFL) in Korean adults. Data were obtained from the 2008–2011 Korea National Health and Nutrition Examination Surveys IV and V (n = 14,015 Koreans aged ≥ 18 years, 64% women). eCRF was calculated with the age- and sex-specific algorithms, and classified as lower (lowest 25%), middle (middle 50%) and upper (highest 25%). Individuals were classified as optimal (i.e., the absence of both sarcopenia and obesity), sarcopenia (i.e., the presence of sarcopenia), obesity (i.e., the presence of obesity) or sarcopenic obesity (i.e., the coexistence of sarcopenia and obesity). Limited to the sarcopenia phenotype, the adjusted odds ratio (OR) of NAFL was 2.2 (95% confidence interval, CI, 1.5–3.1) for the lower eCRF, 1.6 (95% CI, 1.3–2.1) for the middle eCRF and 2.1 (95% CI, 1.4–3.1) for the upper eCRF, compared to the optimal phenotype. Limited to the obesity phenotype, the adjusted OR of NAFL was 2.9 (95% CI, 2.0–4.2) for the lower eCRF, 3.5 (95% CI, 2.7–4.6) for the middle eCRF and 1.8 (95% CI, 1.2–2.8) for the upper eCRF, compared to the optimal phenotype. Limited to the sarcopenic obesity phenotype, the adjusted OR of NAFL was 5.9 (95% CI, 4.3–8.2) for the lower eCRF, 4.2 (95% CI, 3.2–5.5) for the middle eCRF and 2.5 (95% CI, 1.5–4.1) for the upper eCRF, compared to the optimal phenotype. The current findings suggest that high eCRF attenuates the individual and synergistic impacts of sarcopenia and obesity on NAFL in Korean adults.

Molecular Mechanisms Regulating Obesity-Associated Hepatocellular Carcinoma

Obesity is a global, intractable issue, altering inflammatory and stress response pathways, and promoting tissue adiposity and tumorigenesis. Visceral fat accumulation is correlated with primary tumor recurrence, poor prognosis and chemotherapeutic resistance. Accumulating evidence highlights a close association between obesity and an increased incidence of hepatocellular carcinoma (HCC). Obesity drives HCC, and obesity-associated tumorigenesis develops via nonalcoholic fatty liver (NAFL), progressing to nonalcoholic steatohepatitis (NASH) and ultimately to HCC. The better molecular elucidation and proteogenomic characterization of obesity-associated HCC might eventually open up potential therapeutic avenues. The mechanisms relating obesity and HCC are correlated with adipose tissue remodeling, alteration in the gut microbiome, genetic factors, ER stress, oxidative stress and epigenetic changes. During obesity-related hepatocarcinogenesis, adipokine secretion is dysregulated and the nuclear factor erythroid 2 related factor 1 (Nrf-1), nuclear factor kappa B (NF-κB), mammalian target of rapamycin (mTOR), phosphatidylinositol-3-kinase (PI3K)/phosphatase and tensin homolog (PTEN)/Akt, and Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathways are activated. This review captures the present trends allied with the molecular mechanisms involved in obesity-associated hepatic tumorigenesis, showcasing next generation molecular therapeutic strategies and their mechanisms for the successful treatment of HCC.

Beneficial Effects of Insect Extracts on Nonalcoholic Fatty Liver Disease

It is well known that nonalcoholic fatty liver disease (NAFLD) is a common disease worldwide because of unhealthy changes in dietary habits. In this study, we determined the effects of Tenebrio molitor Linnaeus, 1758 extract (TML) and Allomyrina dichotoma Linnaeus, 1771 larvae extract (ADL) in cellular and animal models. In vitro, TML and ADL treatments did not cause cytotoxicity, but attenuated the accumulation of lipid in HepG2 cells induced by free fatty acids. In vivo, mice were orally treated with TML and ADL for 10 weeks during high-fat diet feeding. TML and ADL administration significantly reduced the weight of body, liver tissue, and adipose tissue. Serum lipid profiles, hepatic functional parameters, and glucose levels were ameliorated by TML and ADL. Moreover, TML and ADL suppressed increased lipogenesis and inflammation-related makers, and improved antioxidant enzyme activity. In liver tissue, the decreased lipid accumulation by administration of TML and ADL was observed using Oil Red O and Hematoxylin and Eosin staining. Therefore, we suggest that TML and ADL may be having a therapeutic potential and is used to develop a therapeutic agent for NAFLD.

Exercise Combats Hepatic Steatosis: Potential Mechanisms and Clinical Implications

Hepatic steatosis, the excess storage of intrahepatic lipids, is a rampant clinical problem associated with the obesity epidemic. Hepatic steatosis is linked to increased risk for insulin resistance, type 2 diabetes, and cardiovascular and advanced liver disease. Accumulating evidence shows that physical activity, exercise, and aerobic capacity have profound effects on regulating intrahepatic lipids and mediating susceptibility for hepatic steatosis. Moreover, exercise can effectively reduce hepatic steatosis independent of changes in body mass. In this perspective, we highlight 1) the relationship between obesity and metabolic pathways putatively driving hepatic steatosis compared with changes induced by exercise; 2) the impact of physical activity, exercise, and aerobic capacity compared with caloric restriction on regulating intrahepatic lipids and steatosis risk; 3) the effects of exercise training (modalities, volume, intensity) for treatment of hepatic steatosis, and 4) evidence for a sustained protection against steatosis induced by exercise. Overall, evidence clearly indicates that exercise powerfully regulates intrahepatic storage of fat and risk for steatosis.

Negative Energy Balance Induced by Exercise or Diet: Effects on Visceral Adipose Tissue and Liver Fat

The indisputable association between visceral adipose tissue (VAT) and cardiometabolic risk makes it a primary target for lifestyle-based strategies designed to prevent or manage health risk. Substantive evidence also confirms that liver fat (LF) is positively associated with increased health risk and that reduction is associated with an improved metabolic profile. The independent associations between reductions in VAT, LF, and cardiometabolic risk is less clear. In this narrative review, we summarize the evidence indicating whether a negative energy balance induced by either an increase in energy expenditure (aerobic exercise) or a decrease in energy intake (hypocaloric diet) are effective strategies for reducing both VAT and LF. Consideration will be given to whether a dose-response relationship exists between the negative energy balance induced by exercise or diet and reduction in either VAT or LF. We conclude with recommendations that will help fill gaps in knowledge with respect to lifestyle-based strategies designed to reduce VAT and LF.

The Relationship of VO2 Peak and the Blood Lactate Transition Threshold with Metabolic Syndrome and Its Component Disorders

Background: Improvements in cardiorespiratory fitness attenuate the risk for metabolic syndrome (MetS). However, the determinants of cardiorespiratory fitness measurements such as oxygen consumption (VO₂) peak and anaerobic threshold (AT) have not been investigated in persons with MetS. Therefore, the main aim of this study was to compare VO₂ peak and AT between subjects with and without MetS and to investigate determinants of cardiorespiratory fitness and its effects on the odds for MetS and its individual components. Methods: Thirty-one males with MetS and 24 healthy male participants each performed a VO₂ peak and a blood lactate transition threshold test. Waist circumference, body mass index (BMI), blood pressure, fasting plasma triglyceride, total cholesterol, high-density lipoprotein cholesterol, glucose, and insulin levels were measured. Separate multivariable linear regression models were developed in which VO₂ peak, AT, and the components of MetS were used as the dependent variables, while a multivariable logistic regression model was used for MetS. Results: The VO₂ peak [median (interquartile range)] was lower in subjects with MetS compared with controls [27.9 (23.0-31.0) vs. 35.0 (32.0-45.0) mL·min^-1·kg^-1; P < 0.0001]. Multivariable regression analysis demonstrated that there was a bidirectional association between MetS and VO₂ peak that was mediated by waist circumference and blood pressure. The VO₂ peak was a strong negative determinant of waist circumference (β = -0.36, P < 0.0001), but not of BMI (β = -0.13, P = 0.21). Conclusions: A higher VO₂ peak is associated with a lower odds ratio for MetS, which is related to greater cardiorespiratory fitness in a cyclical relationship that is mediated by blood pressure and waist circumference. A higher VO₂ peak is specifically associated with lower waist circumference, and vice versa, possibly by effects on visceral fat.