Non-alcoholic fatty liver disease

The Renoprotective Mechanisms of Sodium-Glucose Cotransporter-2 Inhibitors (SGLT2i)-A Narrative Review

Chronic kidney disease (CKD) is a noncommunicable condition that has become a major healthcare burden across the globe, often underdiagnosed and associated with low awareness. The main cause that leads to the development of renal impairment is diabetes mellitus and, in contrast to other chronic complications such as retinopathy or neuropathy, it has been suggested that intensive glycemic control is not sufficient in preventing the development of diabetic kidney disease. Nevertheless, a novel class of antidiabetic agents, the sodium-glucose cotransporter-2 inhibitors (SGLT2i), have shown multiple renoprotective properties that range from metabolic and hemodynamic to direct renal effects, with a major impact on reducing the risk of occurrence and progression of CKD. Thus, this review aims to summarize current knowledge regarding the renoprotective mechanisms of SGLT2i and to offer a new perspective on this innovative class of antihyperglycemic drugs with proven pleiotropic beneficial effects that, after decades of no significant progress in the prevention and in delaying the decline of renal function, start a new era in the management of patients with CKD.

Influence of nonalcoholic fatty liver disease on response to antiviral treatment in patients with chronic hepatitis B: A meta-analysis

BACKGROUND

Although hepatitis B virus infection is the leading cause of chronic liver injury globally, nonalcoholic fatty liver disease (NAFLD) is gradually gaining attention as another major chronic liver disease. The number of patients having chronic hepatitis B (CHB) with concomitant hepatic steatosis has increased.

AIM

To analyze the effect of NAFLD on the response to antiviral treatment in patients with CHB.

METHODS

Relevant English studies were systematically searched across PubMed, EMBASE, Web of Science, and Cochrane Library until October 2023. Studies in which the treatment outcomes were compared between patients with CHB only and those with CHB and hepatic steatosis were included.

RESULTS

Of the 2502 retrieved studies, 11 articles were finally included. Biochemical response until 48 wk (OR = 0.87, 95%CI: 0.50-1.53, P = 0.000) and 96 wk (OR = 0.35, 95%CI: 0.24-0.53, P = 0.24) and virological response until 96 wk (OR = 0.80, 95%CI: 0.43-1.49, P = 0.097) were lower in patients with hepatic steatosis than in patients with CHB alone.

CONCLUSION

Hepatic steatosis lowers the biochemical response to antiviral treatment in patients with CHB.

Novel insights into metabolic-associated steatotic liver disease preclinical models

Metabolic-associated steatotic liver disease (MASLD) encompasses a wide spectrum of metabolic conditions associated with an excess of fat accumulation in the liver, ranging from simple hepatic steatosis to cirrhosis and hepatocellular carcinoma. Finding appropriate tools to study its development and progression is essential to address essential unmet therapeutic and staging needs. This review discusses advantages and shortcomings of different dietary, chemical and genetic factors that can be used to mimic this disease and its progression in mice from a hepatic and metabolic point of view. Also, this review will highlight some additional factors and considerations that could have a strong impact on the outcomes of our model to end up providing recommendations and a checklist to facilitate the selection of the appropriate MASLD preclinical model based on clinical aims.

Independent association of hypovitaminosis d with non-alcoholic fatty liver disease in people with chronic spinal cord injury: a cross-sectional study

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) and hypovitaminosis D are highly prevalent in people with spinal cord injury (SCI) and could exert an unfavorable influence on cardiovascular profile and rehabilitation outcomes. We aimed to assess the independent association between low 25-hydroxy vitamin D (25(OH)D) levels and NAFLD in people with chronic (> 1 year) SCI.

METHODS

One hundred seventy-three consecutive patients with chronic SCI (132 men and 41 women) admitted to a rehabilitation program underwent clinical/biochemical evaluations and liver ultrasonography.

RESULTS

NAFLD was found in 105 patients (60.7% of the study population). They were significantly older and exhibited a poorer leisure time physical activity (LTPA) and functional independence in activities of daily living, a greater number of comorbidities and a higher prevalence of metabolic syndrome (MetS) and its correlates, including lower HDL and higher values of body mass index (BMI), systolic blood pressure, HOMA-index of insulin resistance and triglycerides. 25(OH)D levels were significantly lower in NAFLD (median: 10.6 ng/ml, range: 2.0-31.0) than in non-NAFLD group (22.5 ng/ml, 4.2-51.6). When all these variables were included in a multiple logistic regression analysis, a significant independent association with NAFLD only persisted for lower 25(OH)D levels, a greater number of comorbidities and a poorer LTPA. The ROC analysis revealed that 25(OH)D levels < 18.25 ng/ml discriminated patients with NAFLD with a sensitivity of 89.0% and a specificity of 73.0% (AUC: 85.7%; 95%CI: 79.6-91.7%). NAFLD was exhibited by 83.9% of patients with 25(OH)D levels < 18.25 ng/ml and by 18% of those with 25(OH)D levels ≥ 18.25 ng/ml (p < 0.0001).

CONCLUSION

In people with chronic SCI, 25(OH)D levels < 18.25 ng/ml may represent a marker of NAFLD independent of MetS-related features. Further studies are warranted to define the cause-effect relationships of this association.

The Interconnection between Hepatic Insulin Resistance and Metabolic Dysfunction-Associated Steatotic Liver Disease-The Transition from an Adipocentric to Liver-Centric Approach

The central mechanism involved in the pathogenesis of MAFLD is insulin resistance with hyperinsulinemia, which stimulates triglyceride synthesis and accumulation in the liver. On the other side, triglyceride and free fatty acid accumulation in hepatocytes promotes insulin resistance via oxidative stress, endoplasmic reticulum stress, lipotoxicity, and the increased secretion of hepatokines. Cytokines and adipokines cause insulin resistance, thus promoting lipolysis in adipose tissue and ectopic fat deposition in the muscles and liver. Free fatty acids along with cytokines and adipokines contribute to insulin resistance in the liver via the activation of numerous signaling pathways. The secretion of hepatokines, hormone-like proteins, primarily by hepatocytes is disturbed and impairs signaling pathways, causing metabolic dysregulation in the liver. ER stress and unfolded protein response play significant roles in insulin resistance aggravation through the activation of apoptosis, inflammatory response, and insulin signaling impairment mediated via IRE1/PERK/ATF6 signaling pathways and the upregulation of SREBP 1c. Circadian rhythm derangement and biological clock desynchronization are related to metabolic disorders, insulin resistance, and NAFLD, suggesting clock genes as a potential target for new therapeutic strategies. This review aims to summarize the mechanisms of hepatic insulin resistance involved in NAFLD development and progression.

Hepatic, Extra-hepatic Outcomes and Causes of Mortality in NAFLD - An Umbrella Overview of Systematic Review of Meta-Analysis

Background

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease globally. While the prevalence, impact, and causes of mortality have been described in various meta-analyses, a systematic all-encompassing umbrella review has yet to be conducted to consolidate the evidence on outcomes associated with NAFLD.

Methods

Search was conducted on Medline and Embase for meta-analysis investigating associated complications and causes of mortality in NAFLD patients. Summary estimates were presented with original units, sample size, and I2 for heterogeneity. The Assessment of Multiple Systematic Reviews 2 was employed for article selection.

Results

25 meta-analyses were included in the present review. NAFLD increased the risks of systemic complications, including cardiovascular diseases, systemic malignancies, diabetes, and chronic kidney disease. Regarding hepatic outcomes, the incidence of hepatocellular carcinoma in NAFLD was 2.39 per 100 person years (CI: 1.40 to 4.08). Individuals with NAFLD were also found to have an increased likelihood of cholangiocarcinoma (OR: 1.88, CI: 1.25 to 2.83) and gallstone disease (OR: 1.55, CI: 1.31 to 1.82) compared to individuals without NAFLD. NAFLD was associated with a higher risk of fatal and non-fatal CVD events (HR: 1.45, CI: 1.31 to 1.61) compared to individuals without NAFLD. Coronary heart disease and subclinical and clinical coronary heart disease were also significantly elevated in NAFLD individuals compared to individuals without NAFLD. Additionally, NAFLD was associated with an increased risk of all-cause mortality (HR: 1.34, CI: 1.17 to 1.54) and cardiovascular (HR: 1.30, CI: 1.08 to 1.56) but not cancer-related mortality.

Conclusion

The study summarizes high-level evidence from published meta-analyses to provide a much-needed update on the outcomes in patients with NAFLD. The significant systemic burden associated with NAFLD and impending fatty liver epidemic requires prompt action from multidisciplinary providers, policy providers, and stakeholders to reduce the burden of NAFLD.

A new NASH model in aged mice with rapid progression of steatohepatitis and fibrosis

Non-alcoholic fatty liver disease (NAFLD) has a high prevalence worldwide, with a significant proportion of patients progressing into non-alcoholic steatohepatitis (NASH) and further into cirrhosis and hepatocellular carcinoma (HCC). Most of the current animal models of NASH have limitations, such as incompatibility with human pathogenesis characteristics or long induction periods, which severely limit the development of new drugs and preclinical studies for NASH. We investigated the progression of NASH and fibrosis, as well as metabolic indicators, at different time points in aged mice induced by the Gubra Amylin NASH (GAN) diet, a high-fat, high-sugar, high-cholesterol diet, and attempted to establish a rapid and useful mouse model of NASH. Young and aged C57BL/6 mice were induced on a normal chow or GAN diet for 12 and 21 weeks, respectively. After 12 weeks of induction, aged mice developed NASH, including hepatic steatosis, lobular inflammation and hepatic ballooning, and the phenotype was more severe compared with young mice. After 21 weeks of induction, aged mice developed hepatic fibrosis, which greatly shortened the induction time compared with young mice. Furthermore, analysis of immune cell infiltration in the liver by flow cytometry elucidated the changes of multiple immune cells during the pathogenesis of NASH. These findings suggest that aged mice may develop NASH and fibrosis more rapidly under GAN diet induction, which may significantly shorten the period for preclinical studies of NASH.

Hedyotis diffusa alleviate aflatoxin B1-induced liver injury in ducks by mediating Nrf2 signaling pathway

Aflatoxin B1 (AFB1), the most harmful aflatoxins, is a frequent contamination in feed and food items, raising global concerns in animal production and human public health. Also, AFB1 induces oxidative stress, cytotoxicity, mutations, and DNA lesions through its metabolic transformation into aflatoxin B1-8,9-epoxide (AFBO) by cytochrome P450 (CYP450). Hedyotis diffusa (HD) is a traditional Chinese herbal medicine known for its multiple pharmacological activities, including antioxidant, anti-inflammatory, and immunomodulatory. Yet, the influence of HD on AFB1-induced liver injury in ducks is still unknown. Here, we investigated whether HD positively affects AFB1-induced liver injury in ducks. Results revealed that I) AFB1 caused significant changes in serum biochemical indices and decreased growth performance of ducks (such as ALT, AST, ALP, TP, ALB, final body weight, and body weight gain), whereas HD supplementation at 200 mg/kg mitigated these alterations. II) HD alleviated hepatic histopathological changes and liver index induced by AFB1 in ducks. III) HD significantly attenuated AFB1-induced oxidative stress, as measured by increased antioxidant enzyme activities such as SOD, GPx, and T-AOC and decreased MDA levels. Furthermore, HD reduced the level of AFB1-DNA adduct in duck liver. IV) HD significantly promoted the transcriptional expression of NF-E2-related nuclear factor 2 (Nrf2) and associated genes, including heme oxygenase 1 (HO-1), NAD(P)H dehydrogenase quinone 1 (NQO1), glutamate-cysteine ligase catalytic (GCLC). In conclusion, these results demonstrated that HD could activate the Nrf2 pathway in ducks to reduce the hepatotoxicity driven by AFB1. This finding also provides theoretical and data support for a deeper understanding of the toxic mechanisms of AFB1 and its prevention.

Polysaccharides influence human health via microbiota-dependent and -independent pathways

Polysaccharides are the most diverse molecules and can be extracted from abundant edible materials. Increasing research has been conducted to clarify the structure and composition of polysaccharides obtained from different materials and their effects on human health. Humans can only directly assimilate very limited polysaccharides, most of which are conveyed to the distal gut and fermented by intestinal microbiota. Therefore, the main mechanism underlying the bioactive effects of polysaccharides on human health involves the interaction between polysaccharides and microbiota. Recently, interest in the role of polysaccharides in gut health, obesity, and related disorders has increased due to the wide range of valuable biological activities of polysaccharides. The known roles include mechanisms that are microbiota-dependent and involve microbiota-derived metabolites and mechanisms that are microbiota-independent. In this review, we discuss the role of polysaccharides in gut health and metabolic diseases and the underlying mechanisms. The findings in this review provide information on functional polysaccharides in edible materials and facilitate dietary recommendations for people with health issues. To uncover the effects of polysaccharides on human health, more clinical trials should be conducted to confirm the therapeutic effects on gut and metabolic disease. Greater attention should be directed toward polysaccharide extraction from by-products or metabolites derived from food processing that are unsuitable for direct consumption, rather than extracting them from edible materials. In this review, we advanced the understanding of the structure and composition of polysaccharides, the mutualistic role of gut microbes, the metabolites from microbiota-fermenting polysaccharides, and the subsequent outcomes in human health and disease. The findings provide insight into the proper application of polysaccharides in improving human health.

Effect of serum vitamin D on metabolic associated fatty liver disease: a large population-based study

BACKGROUND

Several studies have revealed that serum vitamin D is an important factor for metabolic associated fatty liver disease (MAFLD), but there had been no consistent conclusion.

METHODS

Of 427,507 subjects who underwent health examination, 83,625 who met the inclusion criteria were included in a cross-sectional analysis. Clinical and laboratory data were collected for analysis. MAFLD was diagnosed by abdominal imaging.

RESULTS

Multivariate linear regression models discovered a negative association between serum vitamin D and MAFLD (OR: 0.92, 95% CI: 0.90 to 0.94, p = .001), after adjusting for other well-identified risk factors. The same result was found when serum vitamin D was handled as a categorical variable (quartile, Q1-Q4) (Q4 vs. Q1, OR: 0.82, 95% CI: 0.77 to 0.87, p < .001), and a significant linear trend was observed (p for trend <.001). After analysis, a nonlinear relationship was detected between serum vitamin D and MAFLD, with an inflection point of 2.23 (44.6 nmol/L or 17.84 ng/mL). The effect sizes and the confidence intervals on the left and right sides of the inflection point were 1.16 (1.06 to 1.28) and 0.89 (0.86 to 0.91), respectively. All interactions with MAFLD were not significant for age, sex, diabetes, hypertension, smoking and body mass index (p for interaction = .110, .558, .335, .195, .616 and .401, respectively).

CONCLUSIONS

There was a nonlinear relationship between serum vitamin D and MAFLD. When the serum vitamin D level was ≥44.6 nmol/L (17.84 ng/mL), a negative correlation between serum vitamin D and MAFLD was detected. Below this level, serum vitamin D might promote the progression of MAFLD.

Mitochondrial Dysfunction Plays Central Role in Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a global pandemic that affects one-quarter of the world’s population. NAFLD includes a spectrum of progressive liver disease from steatosis to nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis and can be complicated by hepatocellular carcinoma. It is strongly associated with metabolic syndromes, obesity, and type 2 diabetes, and it has been shown that metabolic dysregulation is central to its pathogenesis. Recently, it has been suggested that metabolic- (dysfunction) associated fatty liver disease (MAFLD) is a more appropriate term to describe the disease than NAFLD, which puts increased emphasis on the important role of metabolic dysfunction in its pathogenesis. There is strong evidence that mitochondrial dysfunction plays a significant role in the development and progression of NAFLD. Impaired mitochondrial fatty acid oxidation and, more recently, a reduction in mitochondrial quality, have been suggested to play a major role in NAFLD development and progression. In this review, we provide an overview of our current understanding of NAFLD and highlight how mitochondrial dysfunction contributes to its pathogenesis in both animal models and human subjects. Further we discuss evidence that the modification of mitochondrial function modulates NAFLD and that targeting mitochondria is a promising new avenue for drug development to treat NAFLD/NASH.

Protective Effects of Naringenin from Citrus sinensis (var. Valencia) Peels against CCl4-Induced Hepatic and Renal Injuries in Rats Assessed by Metabolomics, Histological and Biochemical Analyses

Citrus fruits are grown worldwide for their special nutritive and several health benefits. Among citrus bioactives, naringenin, a major flavanone, exhibits a potential hepatoprotective effect that is not fully elucidated. Herein, serum biochemical parameters and histopathological assays were used to estimate the hepatoprotective activity of naringenin, isolated from Citrus sinensis (var. Valencia) peels, in CCl4-induced injury in a rat model. Further, GC-MS-based untargeted metabolomics was used to characterize the potential metabolite biomarkers associated with its activity. Present results revealed that naringenin could ameliorate the increases in liver enzymes (ALT and AST) induced by CCl4 and attenuate the pathological changes in liver tissue. Naringenin decreased urea, creatinine and uric acid levels and improved the kidney tissue architecture, suggesting its role in treating renal disorders. In addition, naringenin increased the expression of the antiapoptoic cell marker, Bcl-2. Significant changes in serum metabolic profiling were noticed in the naringenin-treated group compared to the CCl4 group, exemplified by increases in palmitic acid, stearic acid, myristic acid and lauric acids and decrease levels of alanine, tryptophan, lactic acid, glucosamine and glucose in CCl4 model rats. The results suggested that naringenin's potential hepato- and renoprotective effects could be related to its ability to regulate fatty acids (FAs), amino acids and energy metabolism, which may become effective targets for liver and kidney toxicity management. In conclusion, the current study presents new insights into the hepato- and renoprotective mechanisms of naringenin against CCl4-induced toxicity.

Association of Serum Vitamin C With NAFLD and MAFLD Among Adults in the United States

Background and Aims

Despite the remarkable progress of metabolic dysfunction-associated fatty liver disease (MAFLD), formerly named non-alcoholic fatty liver disease (NAFLD), the disease remains poorly improved. Since increased oxidative stress and inflammation contribute to the initiation and progression of fatty liver disorders, vitamin C (VC), an antioxidant agent, might be a suitable treatment option for MAFLD. However, the lack of clinically confirmed benefits makes clinicians challenging to recommend antioxidant supplements for MAFLD individuals.

Methods

Herein, the nationally representative National Health and Nutrition Examination Survey 2017–2018 data were collected to evaluate the potential association between the serum VC levels with the risk of different categories of NALFD and the newly proposed MAFLD terminology. Hepatic steatosis was defined as controlled attenuated parameter scores ≥ 263 dB/m, whereas liver fibrosis (LF) status was defined as F0–F4, with the cutoff values of median liver stiffness being 6.3, 8.3, 10.5, and 12.5 (KPa), respectively. A cross-sectional analysis was performed to calculate the odds rate and determine the potential beneficial effects of VC.

Results

A total of 4,494 participants aged more than 18 years and conducted transient elastography examinations were included. Our findings demonstrated that participants with increased serum VC status were more likely to be female predominant, more educated, and moderate drinkers. Interestingly, female participants tended to have a lower prevalence of NAFLD, MAFLD, LF, and liver cirrhosis (LC) after stratification by gender. Moreover, our results revealed that participants from the quartile three group (quartile 3: 50.5–67.0 μmol/L) experienced a slightly lower risk of MAFLD than the risk of NAFLD. Of note, the serum concentration of VC (quartile 2: 30.9–50.5 μmol/L) inversely associated with LF and LC was lower than the serum VC level (quartile 3) associated with NAFLD and MAFLD. Notably, individuals from the quartile 3 group experienced a statistically significant 32.5, 42.0, 45.7, and 71% decrease in risk of NAFLD, MAFLD, LF, and LC, respectively.

Conclusion

In summary, our findings suggested an inverse association between serum VC levels and NAFLD, MAFLD, LF, or LC. Additionally, adjustment of VC supplementation according to age, gender, and ethnicity may be a promising candidate for these diseases.

Beneficial Effects of the Consumption of Hot-Water Extracts of Thinned Immature Mangos (Mangifera indica “Irwin”) on the Hypertriglyceridemia of Apolipoprotein E-Deficient Mice

The thinned immature fruit of the mango tree (Mangifera indica “Irwin”) are regarded as waste products. In this study, we evaluated the effects of daily consumption of a hot-water extract of thinned immature mango fruits (TIMEx) on the dyslipidemia of apolipoprotein E-deficient (ApoE−/−) mice. ApoE−/− mice and wild-type BALB/c mice were fed a 20% fat diet containing 0%, 0.1%, or 1.0% TIMEx for 8 weeks. Their body mass, food intake, and water consumption were unaffected by the TIMEx. The 1.0% TIMEx supplementation significantly reduced serum triglyceride, but not total cholesterol concentration. This effect was significant in ApoE−/− mice, but less marked under normal conditions in wild-type mice. In addition, the circulating concentrations of three hormones that regulate metabolism, resistin, leptin, and glucose-dependent insulinotropic polypeptide, were reduced by TIMEx consumption, which may be involved in its effect to prevent hypertriglyceridemia. However, none of the concentrations of TIMEx reduced the size of atherosclerotic plaque lesions. In conclusion, daily consumption of TIMEx ameliorates hypertriglyceridemia but not hypercholesterolemia in genetically predisposed mice.

Non-Alcoholic Fatty Liver Disease (NAFLD) in Patients with Psoriasis: A Review of the Hepatic Effects of Systemic Therapies

There is increasing interest in the association between psoriasis and non-alcoholic fatty liver disease (NAFLD), which is a prevalent liver disease characterized by excessive fat storage and inflammation that can progress to fibrosis and cancer. Patients with psoriasis have a two-fold higher risk to develop NAFLD and a higher risk to progress to more severe liver disease. Psoriasis and NAFLD share common risk factors such as smoking, alcohol consumption, and the presence of metabolic syndrome and its component disorders. In addition, both psoriasis and NAFLD hinge upon a systemic low-grade inflammation that can lead to a vicious cycle of progressive liver damage in NAFLD as well as worsening of the underlying psoriasis. Other important shared pathophysiological pathways include peripheral insulin resistance and oxidative stress. NAFLD should receive clinical awareness as important comorbidity in psoriasis. In this review, we assess the recent literature on the epidemiological and pathophysiological relationship of psoriasis and NAFLD, discuss the clinical implications of NAFLD in psoriasis patients, and summarize the hepatotoxic and hepatoprotective potential of systemic psoriasis therapies.

Late hepatic toxicity surveillance for survivors of childhood, adolescent and young adult cancer: Recommendations from the international late effects of childhood cancer guideline harmonization group

BACKGROUND

Survivors of childhood, adolescent and young adult (CAYA) cancer may develop treatment-induced chronic liver disease. Surveillance guidelines can improve survivors' health outcomes. However, current recommendations vary, leading to uncertainty about optimal screening. The International Late Effects of Childhood Cancer Guideline Harmonization Group has developed recommendations for the surveillance of late hepatotoxicity after CAYA cancer.

METHODS

Evidence-based methods based on the GRADE framework were used in guideline development. A multidisciplinary guideline panel performed systematic literature reviews, developed evidence summaries, appraised the evidence, and formulated recommendations on the basis of evidence, clinical judgement, and consideration of benefits versus the harms of the surveillance while allowing for flexibility in implementation across different health care systems.

RESULTS

The guideline strongly recommends a physical examination and measurement of serum liver enzyme concentrations (ALT, AST, gGT, ALP) once at entry into long-term follow-up for survivors treated with radiotherapy potentially exposing the liver (moderate- to high-quality evidence). For survivors treated with busulfan, thioguanine, mercaptopurine, methotrexate, dactinomycin, hematopoietic stem cell transplantation (HSCT), or hepatic surgery, or with a history of chronic viral hepatitis or sinusoidal obstruction syndrome, similar surveillance for late hepatotoxicity once at entry into LTFU is reasonable (low-quality evidence/expert opinion, moderate recommendation). For survivors who have undergone HSCT and/or received multiple red blood cell transfusions, surveillance for iron overload with serum ferritin is strongly recommended once at long-term follow-up entry.

CONCLUSIONS

These evidence-based, internationally-harmonized recommendations for the surveillance of late hepatic toxicity in cancer survivors can inform clinical care and guide future research of health outcomes for CAYA cancer survivors.

Similarities and Differences: A Comparative Review of the Molecular Mechanisms and Effectors of NAFLD and AFLD

Non-alcoholic fatty liver disease (NAFLD) and alcoholic fatty liver disease (AFLD) are the most prevalent metabolic liver diseases globally. Due to the complex pathogenic mechanisms of NAFLD and AFLD, no specific drugs were approved at present. Lipid accumulation, oxidative stress, insulin resistance, inflammation, and dietary habits are all closely related to the pathogenesis of NAFLD and AFLD. However, the mechanism that promotes disease progression has not been fully elucidated. Meanwhile, the gut microbiota and their metabolites also play an important role in the pathogenesis and development of NAFLD and AFLD. This article comparatively reviewed the shared and specific signaling pathways, clinical trials, and potential intervention effectors of NAFLD and AFLD, revealing their similarities and differences. By comparing the shared and specific molecular regulatory mechanisms, this paper provides mutual reference strategies for preventing and treating NAFLD, AFLD, and related metabolic diseases. Furthermore, it provides enlightenment for discovering novel therapies of safe and effective drugs targeting the metabolic liver disease.

Non-alcoholic fatty liver and chronic kidney disease: Retrospect, introspect, and prospect

With the growing prevalence of obesity and diabetes in the United States and across the world, a rise in the overall incidence and prevalence of non-alcoholic fatty liver disease (NAFLD) is expected. The risk factors for NAFLD are also associated with the development of chronic kidney disease (CKD). We review the epidemiology, risk factors, genetics, implications of gut dysbiosis, and specific pathogenic mechanisms linking NAFLD to CKD. Mechanisms such as ectopic lipid accumulation, cellular signaling abnormalities, and the interplay between fructose consumption and uric acid accumulation have led to the emergence of potential therapeutic implications for this patient population. Transplant evaluation in the setting of both NAFLD and CKD is also reviewed. Potential strategies for surveillance and management include the monitoring of comorbidities, the use of non-invasive fibrosis scoring systems, and the measurement of laboratory markers. Lastly, we discuss the management of patients with NAFLD and CKD, from preventative measures to experimental interventions.

Relationship of FTO gene variations with NAFLD risk in Chinese men

Background

Fat mass and obesity-associated (FTO) gene is an obesity susceptibility gene and its relationship with the nonalcoholic fatty liver disease (NAFLD) remains unclear. This study aims to investigate the relationships of FTO gene variations with NAFLD risk in a Chinese male population.

Methods

A 1:2 matched case–control study was performed on 275 cases of NAFLD and 550 controls matched for age. Nine of the FTO gene single nucleotide polymorphisms (SNPs) were genotyped.

Results

Logistic regression analysis found that FTO rs1477196 was significantly associated with the susceptibility to NAFLD in recessive genetic models [unadjusted odds ratio (OR) = 2.52, 95% confidence interval (CI): 1.22–5.19, P = 0.012] and the relativity weakened after further adjustment for body mass index (BMI), uric acid, metabolic syndrome, smoking, and drinking (adjusted OR = 2.18, 95% CI: 0.96–4.99, P = 0.06). In the obese group, the AA + AG genotypes of rs1121980 and rs9940128 were associated with a decreased risk of NAFLD, when compared with the GG genotype, respectively (rs1121980: adjusted OR = 0.62, 95% CI = 0.39–0.99, P = 0.044; rs9940128: adjusted OR = 0.61, 95% CI = 0.38–0.97, P = 0.038). Furthermore, rs1477196 was associated with the severity of NAFLD (OR = 2.95, 95% CI = 1.09–7.94, P = 0.034).

Conclusions

Our results demonstrated that the FTO gene was related to the presence and severity of NAFLD in a Chinese male population, and the relationships of the tested SNPs with NAFLD are most probably mediated by BMI.

Non-Alcoholic Fatty Liver Disease in Obese Youth With Insulin Resistance and Type 2 Diabetes

Currently, Non-Alcoholic Fatty Liver Disease (NAFLD) is the most prevalent form of chronic liver disease in children and adolescents worldwide. Simultaneously to the epidemic spreading of childhood obesity, the rate of affected young has dramatically increased in the last decades with an estimated prevalence of NAFLD of 3%-10% in pediatric subjects in the world. The continuous improvement in NAFLD knowledge has significantly defined several risk factors associated to the natural history of this complex liver alteration. Among them, Insulin Resistance (IR) is certainly one of the main features. As well, not surprisingly, abnormal glucose tolerance (prediabetes and diabetes) is highly prevalent among children/adolescents with biopsy-proven NAFLD. In addition, other factors such as genetic, ethnicity, gender, age, puberty and lifestyle might affect the development and progression of hepatic alterations. However, available data are still lacking to confirm whether IR is a risk factor or a consequence of hepatic steatosis. There is also evidence that NAFLD is the hepatic manifestation of Metabolic Syndrome (MetS). In fact, NAFLD often coexist with central obesity, impaired glucose tolerance, dyslipidemia, and hypertension, which represent the main features of MetS. In this Review, main aspects of the natural history and risk factors of the disease are summarized in children and adolescents. In addition, the most relevant scientific evidence about the association between NAFLD and metabolic dysregulation, focusing on clinical, pathogenetic, and histological implication will be provided with some focuses on the main treatment options.

Non-invasive Assessment of Liver Fat in ob/ob Mice Using Ultrasound-Induced Thermal Strain Imaging and Its Correlation with Hepatic Triglyceride Content

Non-alcoholic fatty liver disease is the accumulation of triglycerides in liver. In its malignant form, it can proceed to steatohepatitis, fibrosis, cirrhosis, cancer and ultimately liver impairment, leading to liver transplantation. In a previous study, ultrasound-induced thermal strain imaging (US-TSI) was used to distinguish between excised fatty livers from obese mice and non-fatty livers from control mice. In this study, US-TSI was used to quantify lipid composition of fatty livers in ob/ob mice (n = 28) at various steatosis stages. A strong correlation coefficient was observed (R² = 0.85) between lipid composition measured with US-TSI and hepatic triglyceride content. Hepatic triglyceride content is used to quantify adipose tissue in liver. The ob/ob mice were divided into three groups based on the degree of steatosis that is used in clinics: none, mild and moderate. A non-parametric Kruskal-Wallis test was conducted to determine if US-TSI can potentially differentiate among the steatosis grades in non-alcoholic fatty liver disease.

Multifocal Nodular Fatty Infiltration of the Liver: A Rare Benign Disorder That Mimics Metastatic Liver Disease

Fatty liver disease is a frequent diagnosis. Rarely, it adopts a multifocal nodular pattern mimicking multiple liver metastases. Multifocal nodular fatty infiltration of the liver entails a challenging problem that must be included as a differential diagnosis when dealing with healthy patients with an incidental finding of multiple liver lesions, even in the absence of obesity or metabolic syndrome. A complete clinical examination and high-quality imaging, including magnetic resonance imaging, might help to confirm diagnosis and to avoid unnecessary liver biopsies.

Stress kinases in the development of liver steatosis and hepatocellular carcinoma

Non-alcoholic fatty liver disease (NAFLD) is an important component of metabolic syndrome and one of the most prevalent liver diseases worldwide. This disorder is closely linked to hepatic insulin resistance, lipotoxicity, and inflammation. Although the mechanisms that cause steatosis and chronic liver injury in NAFLD remain unclear, a key component of this process is the activation of stress-activated kinases (SAPKs), including p38 and JNK in the liver and immune system. This review summarizes findings which indicate that the dysregulation of stress kinases plays a fundamental role in the development of steatosis and are important players in inducing liver fibrosis. To avoid the development of steatohepatitis and liver cancer, SAPK activity must be tightly regulated not only in the hepatocytes but also in other tissues, including cells of the immune system. Possible cellular mechanisms of SAPK actions are discussed.

•

Hepatic JNK triggers steatosis and insulin resistance, decreasing lipid oxidation and ketogenesis in HFD-fed mice.

•

Decreased liver expression of p38α/β in HFD increases lipogenesis.

•

Hepatic p38γ/δ drive insulin resistance and inhibit autophagy, which may lead to steatosis.

•

Macrophage p38α/β promote cytokine production and M1 polarization, leading to lipid accumulation in hepatocytes.

•

Myeloid p38γ/δ contribute to cytokine production and neutrophil migration, protecting against steatosis, diabetes and NAFLD.

•

JNK1 and p38γ induce HCC while p38α blocks it. However, deletion of hepatic JNK1/2 induces cholangiocarcinoma.

•

SAPK are potential therapeutic target for metabolic disorders, steatohepatitis and liver cancer.

Non-alcoholic fatty liver disease: An overview of risk factors, pathophysiological mechanisms, diagnostic procedures, and therapeutic interventions

Non-alcoholic fatty liver disease (NAFLD) is a disorder of excessive fat accumulation in the liver, known as steatosis, without alcohol overconsumption. NAFLD can either manifest as simple steatosis or steatohepatitis, known as non-alcoholic steatohepatitis (NASH), which is accompanied by inflammation and possibly fibrosis. Furthermore, NASH might progress to hepatocellular carcinoma. NAFLD and NASH prevalence is in a continuous state of growth, and by 2018, NAFLD became a devastating metabolic disease with a global pandemic prevalence. The pathophysiology of NAFLD and NASH is not fully elucidated, but is known to involve the complex interplay between different metabolic, environmental, and genetic factors. In addition, unhealthy dietary habits and pre-existing metabolic disturbances together with other risk factors predispose NAFLD development and progression from simple steatosis to steatohepatitis, and eventually to fibrosis. Despite their growing worldwide prevalence, to date, there is no FDA-approved treatment for NAFLD and NASH. Several off-label medications are used to target disease risk factors such as obesity and insulin resistance, and some medications are used for their hepatoprotective effects. Unfortunately, currently used medications are not sufficiently effective, and research is ongoing to investigate the beneficial effects of different drugs and phytochemicals in NASH. In this review article, we outline the different risk factors and pathophysiological mechanisms involved in NAFLD, diagnostic procedures, and currently used management techniques.

Pathogenesis of NASH and Promising Natural Products

Nonalcoholic steatohepatitis (NASH) is a common clinical condition that can lead to advanced liver diseases. The mechanism of the diaease progression, which is lacking effective therapy, remains obsure. Therefore, there is a need to understand the pathogenic mechanisms responsible for disease development and progression in order to develop innovative therapies. To accomplish this goal, experimental animal models that recapitulate the human disease are necessary. Currently, an increasing number of studies have focused on natural constituents from medicinal plants which have been emerged as a new hope for NASH. This review summarized the pathogenesis of NASH, animal models commonly used, and the promising targets for therapeutics. We also reviewed the natural constituents as potential NASH therapeutic agents.

Adipose tissue remodelling in obese subjects is a determinant of presence and severity of fatty liver disease

AIMS

Experimental data suggest that visceral adipose tissue (VAT) dysfunction contributes to non-alcoholic fatty liver disease (NAFLD) development in obesity, however, data on humans are limited. Aims of this study were to investigate the relationship between NAFLD and VAT morphofunctional impairment and to determine whether the extent of VAT remodelling is associated with liver damage and metabolic alterations in obesity.

METHODS

We analysed data from 40 obese individuals candidate to bariatric surgery in whom paired intraoperative liver and omental biopsies were performed for diagnosing NAFLD and VAT inflammation by immunohistochemistry and mRNA expression studies.

RESULTS

Within our study population, NAFLD was significantly associated with greater VAT CD68⁺ macrophages infiltration (P = .04), fibrosis (P = .04) and impaired microvascular density (P = .03) as well as increased expression of markers of local hypoxia, apoptosis and inflammation (UNC5B, CASP7, HIF1-α, IL-8, MIP2, WISP-1, all P < .01). The degree of VAT inflammation correlated with the severity of hepatic injury (steatosis, inflammation, fibrosis; all P < .01) and impaired gluco-metabolic profile.

CONCLUSIONS

In obese patients, NAFLD is associated in a dose-dependent manner with signs of VAT remodelling, which reflect more severe clinical metabolic impairment. Our study depicts morphological alterations and novel mediators of VAT dysfunction, adding knowledge for future therapeutic approaches to NAFLD and its metabolic complications.

Screening for nonalcoholic fatty liver disease in patients with type 2 diabetes mellitus using transient elastography - a prospective, cross sectional study

AIM

To investigate the prevalence and severity of nonalcoholic fatty liver disease (NAFLD) in patients with diabetes mellitus type 2 (T2DM), based on increased controlled attenuation parameter (CAP) and liver stiffness measurements obtained by transient elastography. In addition, we aimed to identify parameters that correlate with increased elastographic parameters of steatosis and fibrosis to provide a better indication when a patient with T2DM should be screened for NAFLD.

METHODS

We conducted prospective, cross-sectional study of 679 consecutive adult patients with diagnosed T2DM mean age 65.2±11.6. NAFLD was defined by transient elastography. In 105 patients a percutaneous liver biopsy (LB) was done.

RESULTS

The prevalence of NAFLD based on transient elastography was 83.6%. Independent factors associated with increased CAP were higher body mass index, longer T2DM duration, higher serum triglyceride, lower levels of vitamin D, higher C-reactive protein, and higher HOMA-IR. The prevalence of moderate liver fibrosis was 26.9% and advanced liver fibrosis 12.6%. Independent factors associated with moderated fibrosis based on elastography were higher body mass index and higher levels of alanine aminotransferase (ALT), while independent factors associated with advanced fibrosis were female gender, higher body mass index, higher levels of ALT, gama-glutamil transferase and C-reactive protein. Sixty-four (60.9%) of 105 patients with LB had NAFLD activity score ≥5. Regarding the presence and stages of fibrosis based on LB, moderate fibrosis was found in 29.5% of patients, while 29.5% had advanced fibrosis and 6.7% cirrhosis.

CONCLUSION

This study supports more aggressive screening for NAFLD and fibrosis in patients with T2DM.

Inositol-requiring enzyme 1α links palmitate-induced mTOR activation and lipotoxicity in hepatocytes

Hepatic lipotoxicity, hepatocyte dysfunction/cell death induced by saturated fatty acids (SFA), plays a central role in the pathogenesis of nonalcoholic fatty liver disease (NAFLD); however, the underlying mechanisms remain unclear. Palmitate is the most abundant SFA in the circulation. In this study, via a small-scale screening of chemical inhibitors using AML12 hepatocytes, we identified mechanistic target of rapamycin (mTOR) complex 1 (mTORC1) to be a culprit in palmitate-induced cell death in hepatocytes in that mTOR inhibition is protective against palmitate-induced cell death. The protective effect of mTORC1 inhibition is independent of autophagy induction, as autophagy inhibition failed to ablate the mTORC1 inhibitor-conferred protection. We have previously reported that the endonuclease activity of inositol-requiring enzyme 1α (IRE1α), one of three canonical signaling pathways of endoplasmic reticulum (ER) stress, was implicated in palmitate-induced cell death in hepatocytes. The continuous mechanistic investigation in this study uncovered that IRE1α is a downstream target of mTORC1 activation upon palmitate exposure and the inhibition of either its endonuclease activity or kinase activity protects against the lipotoxic effect of palmitate. Our research further revealed that protein palmitoylation is potentially involved in palmitate-induced mTORC1 activation and lipotoxicity in hepatocytes. 2-Bromopalmitate, a protein palmitoylation inhibitor, ameliorated palmitate-triggered mTORC1 activation, concomitant with the protection of lipotoxicity in hepatocytes. Collectively, our data have identified that mTORC1 and ER stress are coordinately implicated in hepatocyte cell death in response to palmitate exposure and suggest that this pathway may potentially serve as a therapeutic target for the treatment of NAFLD as well as other metabolic disorders involving lipotoxicity.

The association of nonalcoholic steatohepatitis and hepatocellular carcinoma

BACKGROUND

Current guidelines recommend surveillance for hepatocellular carcinoma (HCC) in high-risk patients. This high risk is defined by the presence of cirrhosis. However, HCC due to underlying nonalcoholic steatohepatitis (NASH), even without progressing to cirrhosis, is a rising concern. Hence, we aimed to determine the association of HCC with NASH using a large national database.

METHODS

A cross-sectional study was performed using the 2012 National Inpatient Sample. The study group was all adult patients' age 18-90 years who have a diagnosis of NASH which was identified using the International Classification of Diseases 9th version (ICD-9) codes. The control group included the rest of adult individuals without discharge records of NASH. We identified the diagnosis of HCC in both study and control groups using the ICD-9 codes. We calculated the association between NASH and HCC using univariable and multivariate logistic regression.

RESULTS

Totally, 30 712 524 hospitalizations were included in our study. This cohort included 218 950 patients with NASH (study group) and 30 493 574 patients without NASH (control group). The study group patients aged 57.3 ± 0.10 years (59.4% females) comparing to 54.5 ± 0.11 years (57.1% female) in the control group. HCC prevalence in subjects with NASH was 0.50% [95% confidence interval (CI): 0.41-0.59] compared to 0.21% (95% CI: 0.20-0.23) in subjects without NASH (P < 0.001). After adjusting for age, gender, smoking, alcohol use, obesity, hepatitis C virus, hepatitis B virus, hemochromatosis, HIV, cirrhosis and the modified comorbidity index, subjects with NASH were 60% more likely to have HCC than those without NASH (adjusted odds ratio: 1.6, 95% CI: 1.4-1.9, P < 0.001).

CONCLUSION

Our study showed that NASH patients are 60% more likely to develop HCC compared with patients without NASH. Close monitoring and even periodical surveillance might be needed.

The pivotal role of heme Oxygenase-1 in reversing the pathophysiology and systemic complications of NAFLD

The pathogenesis and molecular pathways involved in non-alcoholic fatty liver disease (NAFLD) are reviewed, as well as what is known about mitochondrial dysfunction that leads to heart disease and the progression to steatohepatitis and hepatic fibrosis. We focused our discussion on the role of the antioxidant gene heme oxygenase-1 (HO-1) and its nuclear coactivator, peroxisome proliferator-activated receptor-gamma coactivator (PGC1-α) in the regulation of mitochondrial biogenesis and function and potential therapeutic benefit for cardiac disease, NAFLD as well as the pharmacological effect they have on the chronic inflammatory state of obesity. The result is increased mitochondrial function and the conversion of white adipocyte tissue to beige adipose tissue ("browning of white adipose tissue") that leads to an improvement in signaling pathways and overall liver function. Improved mitochondrial biogenesis and function is essential to preventing the progression of hepatic steatosis to NASH and cirrhosis as well as preventing cardiovascular complications.

TCTP participates in hepatic metabolism by regulating gene expression involved in insulin resistance

Translationally controlled tumor protein (TCTP) has various cellular functions and molecular interactions, many related to its growth-promoting and antiapoptotic properties. Recently, TCTP expression was reported to increases in insulin-resistant mice fed with high-fat diet. TCTP is a multifunctional protein, but its role in liver metabolism is unclear. Here, we investigated the function and mechanism of TCTP in HepG2 cells. Knock-down of TCTP led to 287 differentially expressed genes (DEGs) that were highly associated with cellular apoptosis and signal response, TNF and NF-κB signaling pathways, glycolysis/gluconeogenesis, insulin resistance, FoxO and insulin signaling pathways, adipocytokine and AMPK signaling pathways. shTCTP downregulated the expression of the key gluconeogenesis enzyme phosphoenolpyruvate carboxykinase (PCK1). Furthermore, TCTP regulated the alternative splicing of genes enriched in the phospholipid biosynthetic process and glycerophospholipid metabolism. We further showed that shTCTP down-regulated the intracellular levels of triglyceride and total cholesterol. Our results showed that TCTP regulates the liver cell transcriptome at both the transcriptional and alternative splicing levels. The TCTP regulatory network predicts the biological functions of TCTP in glucose and lipid metabolism, and also insulin resistance, which may be associated with liver metabolism and diseases such as nonalcoholic fatty liver disease.

Changes in alanine aminotransferase in adults with severe and complicated obesity during a milk-based meal replacement programme

Introduction

Excess adiposity is associated with fat accumulation within the liver, and non-alcoholic steatohepatitis (NASH) is highly prevalent in bariatric patients. Elevated alanine aminotransferase (ALT) is associated with prevalent NASH. We sought to determine the influence of a milk-based meal replacement weight-loss programme on ALT levels in adults with severe and complicated obesity.

Methods

We conducted a retrospective cohort study of patients who completed a 24-week meal replacement programme, comprised of a weight loss phase followed by weight stabilisation and maintenance phases, each 8 weeks long. ALT was quantified using an enzymatic assay with spectrophotometric detection. We examined changes over time in ALT using the non-parametric Wilcoxon singed-rank test and the Friedman test.

Results

Of 105 patients, 56 were female, mean age was 51.2 ± 11.2 (range 18.0–71.6) years. There was an unanticipated but transient increase in ALT from 28.0 [20.0, 40.5] iu/L at baseline to 40.0 [26.0, 55.0] iu/L after 2 weeks (p < 0.0005), followed by a gradual reduction to 21.0 [17.0, 28.3] iu/L by 24 weeks (p < 0.0005). The overall reductions in ALT were more pronounced in patients who had elevated levels at baseline. Body weight decreased from 144.2 ± 28.0 kg at baseline to 121.6 ± 25.4 kg at 24 weeks (p < 0.0005) and body mass index (BMI) decreased from 50.7 ± 8.1 kg m⁻² at baseline to 43.0 ± 7.6 kg m⁻² by 24 weeks (p < 0.0005).

Conclusion

In adults with severe and complicated obesity undergoing a milk-based meal replacement programme, there was an initial unanticipated rise in ALT in the first 2 weeks, followed by a gradual overall reduction by 24 weeks. These findings suggest that rapid weight loss secondary to significant caloric restriction might induce a transient deterioration in hepatic steatosis prior to an ultimate overall improvement.

Increased risks of different grades of non-alcoholic fatty liver disease in prediabetic subjects with impaired fasting glucose and glucose tolerance, including the isolated glycosylated hemoglobin levels of 5.7-6.4% in a Chinese population

AIMS/INTRODUCTION

Contrary to the results of the majority of studies on diabetes, there are some conflicting results regarding the relationship between non-alcoholic fatty liver disease (NAFLD) and prediabetes. No study has investigated the relationship between isolated glycated hemoglobin (HbA1c) in the range of 5.7-6.4% (HbA1c 5.7-6.4%) and NAFLD. Our aim was to investigate the effect of different glycemic statuses on NAFLD concomitantly categorized by fasting plasma glucose, 2-h plasma glucose and HbA1c levels.

MATERIALS AND METHODS

NAFLD was classified into three groups by ultrasonographic examination results: normal, mild and moderate-to-severe. Glycemic status was divided into five groups: normoglycemia, isolated HbA1c 5.7-6.4%, impaired fasting glucose without impaired glucose tolerance (IGT), IGT and newly diagnosed diabetes. For multivariable logistic regression analyses, the outcome variable was the classified three grades of fatty changes in the liver after adjusting for other potential risk covariables.

RESULTS

In this cross-sectional research, a total of 8,571 eligible individuals were enrolled and divided into three groups: 5,499 without fatty liver, 2,113 with mild NAFLD and 959 with moderate-to-severe NAFLD. Multivariable logistic regression analysis showed that IGT, impaired fasting glucose without IGT and isolated HbA1c 5.7-6.4% were associated with a higher risk of NAFLD in addition to newly diagnosed diabetes. Other positively predictive variables were male sex, obesity, overweight, central obesity, increased triglyceride and C-reactive protein >1 mg/L. Negatively associated factors were elevated high-density lipoprotein cholesterol levels.

CONCLUSIONS

Besides diabetes, the increased risks of different grades of NAFLD were found for prediabetic individuals categorized by impaired fasting glucose without IGT, IGT and isolated HbA1c 5.7-6.4%.

Molecular Study on the Potential Protective Effects of Bee Venom against Fructose-Induced Nonalcoholic Steatohepatitis in Rats

BACKGROUND

There is a causative relation between the increased hepatic steatohepatitis prevalence and sweeteners intake, fructose in particular. Despite an increasing understanding of the mechanisms of nonalcoholic steatohepatitis (NASH) pathogenesis, there are no drugs approved for it.

OBJECTIVES

Evaluate the effect of bee venom (BV) treatment on the fructose-induced NASH in rats and demonstrate its possible molecular mechanisms.

METHODS

NASH was induced in rats by 10% fructose in drinking water for 8 weeks. BV was administered (0.1 mg/kg, i.p.) 3 times per week during the last 2 weeks of the experiment. Sera were used for the determination of lipids, cholesterol, glucose, insulin, and liver enzymes. Hepatic gene expressions of farnesoid X receptor (FXR)α and the liver X receptor (LXR) were determined. Hepatic sterol regulatory element-binding protein (SREBP)1/2, oxidative stress, and inflammation parameters were measured. Liver parts were used for histopathological examination. Small intestine was removed for the determination of tight junction proteins.

RESULTS

Fructose caused overt histological damage in the liver, and this was associated with parallel changes in all parameters measured. BV effectively prevented these changes, presumably through amelioration of hepatic SREBP1/2, LXR, and FXRα expression as well as intestinal tight junction proteins.

CONCLUSION

These findings support the therapeutic usefulness of BV, a remedy with a favorable safety profile, in the prevention of fructose-induced NASH.

Effect of Exercise on NAFLD and Its Risk Factors: Comparison of Moderate versus Low Intensity Exercise

Background and Aims: Lifestyle (exercise and dietary) modification is the mainstay of treatment for non-alcoholic fatty liver disease (NAFLD). However, there is paucity of data on effect of intensity of exercise in management of NAFLD, and we aimed to study the effect of variable intensities of exercise on NAFLD. Methods: The study was performed in the Department of Gastroenterology of the SCB Medical College, Cuttack and the Biju Patnaik State Police Academy, Bhubaneswar. The subjects were police trainees [18 in a moderate intensity exercise group (MIG) and 19 in a low intensity exercise group (LIG)] recruited for a 6-month physical training course (261.8 Kcalorie, 3.6 metabolic equivalent in MIG and 153.6 Kcalorie, 2.1 metabolic equivalent in LIG). NAFLD was diagnosed by ultrasonography, with exclusion of all secondary causes of steatosis. All participants were evaluated by anthropometry (weight, height, body mass index (BMI), waist circumference), assessed for blood pressure and biochemical parameters (blood glucose, liver function test, lipid profile, serum insulin), and subjected to transabdominal ultrasonography before and after 6 months of physical training, and the results were compared. Results: Both the groups had similar BMI, fasting plasma glucose, AST, gamma-glutamyl transpeptidase, insulin, and homeostatic model assessment-insulin resistance (known as HOMA-IR) (p>0.05). However, subjects in the LIG were older and had lower alanine transaminase, higher triglycerides and lower high-density lipoproteins than MIG subjects. There was a significant reduction in BMI (27.0±2.1 to 26.8±2.0; p=0.001), fasting blood glucose (106.7±21.6 to 85.8±19.0; p<0.001), serum triglycerides (167.5±56.7 to 124.6±63.5; p=0.017), total cholesterol (216.8±29.2 to 196.7±26.6; p=0.037), low-density lipoprotein cholesterol (134.6±21.4 to 130.5±21.9; p=0.010), serum aspartate transaminase (39.3±32.2 to 30.9±11.4; p<0.001), serum alanine transaminase (56.6±28.7 to 33.0±11.3; p<0.001) and HOMA-IR (2.63±2.66 to 1.70±2.59; p<0.001) in the MIG. However, changes in these parameters in the LIG were non-significant. Hepatic steatosis regressed in 66.7% of the NAFLD subjects in the MIG but in only 26.3% of the LIG NAFLD subjects (p=0.030). Conclusions: Moderate rather than low intensity physical activity causes significant improvement in BMI, serum triglycerides, cholesterol, serum transaminases and HOMA-IR, and regression of ultrasonographic fatty change in liver among NAFLD subjects.

The PPAR α/γ Agonist Saroglitazar Improves Insulin Resistance and Steatohepatitis in a Diet Induced Animal Model of Nonalcoholic Fatty Liver Disease

Insulin resistance and hepatic lipid accumulation constitute the metabolic underpinning of nonalcoholic steatohepatitis (NASH). We tested the hypothesis that saroglitazar, a PPAR α/γ agonist would improve NASH in the diet-induced animal model of NAFLD. Mice received chow diet and normal water (CDNW) or high fat western diet and ad lib sugar water (WDSW). After 12 weeks, WDSW fed mice were randomized to receive (1) WDSW alone, (2) WDSW + vehicle, (3) WDSW + pioglitazone or (4) WDSW + saroglitazar for an additional 12 weeks. Compared to mice on WDSW and vehicle controls, mice receiving WDSW + saroglitazar had lower weight, lower HOMA-IR, triglycerides, total cholesterol, and ALT. Saroglitazar improved steatosis, lobular inflammation, hepatocellular ballooning and fibrosis stage. NASH resolved in all mice receiving saroglitazar. These effects were at par with or superior to pioglitazone. Molecular analyses confirmed target engagement and reduced oxidative stress, unfolded protein response and fibrogenic signaling. Transcriptomic analysis further confirmed increased PPAR-target expression and an anti-inflammatory effect with saroglitazar. Lipidomic analyses demonstrated that saroglitazar also reduced triglycerides, diglycerides, sphingomyelins and ceramides. These preclinical data provide a strong rationale for developing saroglitazar for the treatment of NASH in humans.

Absence of Bsep/Abcb11 attenuates MCD diet-induced hepatic steatosis but aggravates inflammation in mice

BACKGROUND

Bile acids (BAs) regulate hepatic lipid metabolism and inflammation. Bile salt export pump (BSEP) KO mice are metabolically preconditioned with a hydrophilic BA composition protecting them from cholestasis. We hypothesize that changes in hepatic BA profile and subsequent changes in BA signalling may critically determine the susceptibility to steatohepatitis.

METHODS

Wild-type (WT) and BSEP KO mice were challenged with methionine choline-deficient (MCD) diet to induce steatohepatitis. Serum biochemistry, lipid profiling as well as intestinal lipid absorption were assessed. Markers of inflammation, fibrosis, lipid and BA metabolism were analysed. Hepatic and faecal BA profile as well as serum levels of the BA synthesis intermediate 7-hydroxy-4-cholesten-3-one (C4) were also investigated.

RESULTS

Bile salt export pump KO MCD-fed mice developed less steatosis but more inflammation than WT mice. Intestinal neutral lipid levels were reduced in BSEP KO mice at baseline and under MCD conditions. Faecal non-esterified fatty acid concentrations at baseline and under MCD diet were markedly elevated in BSEP KO compared to WT mice. Serum liver enzymes and hepatic expression of inflammatory markers were increased in MCD-fed BSEP KO animals. PPARα protein levels were reduced in BSEP KO mice. Accordingly, PPARα downstream targets Fabp1 and Fatp5 were repressed, while NFκB subunits were increased in MCD-fed BSEP KO mice. Farnesoid X receptor (FXR) protein levels were reduced in MCD-fed BSEP KO vs WT mice. Hepatic BA profile revealed elevated levels of TβMCA, exerting FXR antagonistic action, while concentrations of TCA (FXR agonistic function) were reduced.

CONCLUSION

Presence of hydroxylated BAs result in increased faecal FA excretion and reduced hepatic lipid accumulation. This aggravates development of MCD diet-induced hepatitis potentially by decreasing FXR and PPARα signalling.

Metabolic inflammation as an instigator of fibrosis during non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is characterized by excessive storage of fatty acids in the form of triglycerides in hepatocytes. It is most prevalent in western countries and includes a wide range of clinical and histopathological findings, namely from simple steatosis to steatohepatitis and fibrosis, which may lead to cirrhosis and hepatocellular cancer. The key event for the transition from steatosis to fibrosis is the activation of quiescent hepatic stellate cells (qHSC) and their differentiation to myofibroblasts. Pattern recognition receptors (PRRs), expressed by a plethora of immune cells, serve as essential components of the innate immune system whose function is to stimulate phagocytosis and mediate inflammation upon binding to them of various molecules released from damaged, apoptotic and necrotic cells. The activation of PRRs on hepatocytes, Kupffer cells, the resident macrophages of the liver, and other immune cells results in the production of proinflammatory cytokines and chemokines, as well as profibrotic factors in the liver microenvironment leading to qHSC activation and subsequent fibrogenesis. Thus, elucidation of the inflammatory pathways associated with the pathogenesis and progression of NAFLD may lead to a better understanding of its pathophysiology and new therapeutic approaches.

The association between education level and chronic liver disease of any etiology

BACKGROUND

The potential link between educational level and chronic liver diseases (CLD) were explored using the mortality records of liver cirrhosis, which lack accuracy and are unable to identify the different etiological factors of liver cirrhosis. Information on the association of low educational level with the severity of CLD is lacking.

AIM

To evaluate the potential association linking education level to etiology and clinical stage of CLD cases.

METHODS

Consecutive enrolment of 11,107 subjects with CLD aged≥18 years prospectively recruited in two national surveys in 2001 and 2014 at one of the participating Italian liver units throughout the country. Subjects were pooled in two groups: low education level (less than high school) and high education level (completed high school or beyond). The association of demographic, etiological, and clinical stage of subjects with educational level was assessed using logistic regression analysis. In the analysis low educational level was the outcome variable.

RESULTS

A total of 11,107 subjects born in Italy (mean age 55.5 years, sex ratio 1.5) were evaluated. Multiple logistic regression analysis shows that chronic HCV infection (O.R.1,38:95%,C.I.1.23-1.55), risky alcohol intake (O.R.1.96;95%,C.I.1.73-2.21) and liver cirrhosis (O.R.1.65;95%,C.I.1.46-1.85) all resulted independently associated with less than a completed high school education. HBV infection resulted independently associated with high education level (O.R.0.74;95%,C.I.0.64-0.86), reflecting changes in HBV modes of transmission in recent decades. No association was found with CLD related to non-alcoholic fatty liver disease (O.R.1.03;95%, C.I.0.81-1.30).

CONCLUSIONS

These findings show an independent association linking education level with viruses and alcohol-related CLD. Low educational level is associated with the severity of CLD.

Association of nonalcoholic fatty liver disease with serum vitamin D levels in combination of physical fitness in korean older adults

The prevalence of non-alcoholic fatty liver disease (NAFLD) tends to increase with age, but little is known regarding relations between the risk of NAFLD in older adults and serum vitamin D (25-hydroxyvitamin D) and physical fitness levels. The aim of this study was to investigate the relationship between NAFLD risk and serum vitamin D levels combined with physical fitness in elderly adults using a non-invasive diagnostic approach. We enrolled 533 Korean older adults (80.8 % women), aged 65 years or older in this cross-sectional study. NAFLD in absence of another cause of liver disease was defined according to the ZJU and NAFLD liver fat (LFS) score. Physical fitness was assessed using a senior fitness test protocol. Logistic regression analysis was used to estimate odds ratios (ORs) and 95 % confidence intervals (CIs) of NAFLD for different combinations of serum vitamin D and physical fitness levels. According to the ZJU (OR: 3.073, CI: 1.285-7.350, p = 0.012) and LFS (OR = 2.443, CI = 1.071-5.572, p = 0.034), individuals with serum vitamin D < 30 ng/ml and poor physical fitness had a significantly higher risk of NAFLD than individuals with serum vitamin D ≥ 30 ng/ml and high fitness (reference, OR = 1), even after adjustments for age, sex, smoking, alcohol consumption and physical inactivity. However, there was no significant association after adjustment for additional metabolic diseases. Our findings suggest that the maintenance of appropriate levels of serum vitamin D and/or high physical fitness and the monitoring metabolic diseases can help reduce the risk of NAFLD in older adults.

Hepatoprotective effects of Shilajit on high fat-diet induced non-alcoholic fatty liver disease (NAFLD) in rats

Background Non-alcoholic fatty liver disease (NAFLD) is the main common cause of chronic liver disease. The aim of this study is to evaluate the effect of Shilajit, a medicine of Ayurveda, on the liver damage caused by NAFLD. Materials and methods Forty male Wistar rats, after being established as fatty liver models by feeding a high-fat diet (HFD, 12 weeks), were divided randomly into five groups as follows: control (standard diet), vehicle (HFD + distilled water), high-dose Shilajit (HFD + 250 mg/kg Shilajit), low-dose Shilajit (HFD + 150 mg/kg Shilajit) and pioglitazone (HFD + 10 mg/kg pioglitazone). The serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglycerides (TG), total cholesterol (TC), low-density lipoprotein (LDL), glucose and liver glutathione peroxidase (GPx), superoxide dismutase (SOD) activity, malondialdehyde (MDA) levels, liver weight, and histopathological manifestation outcomes were measured after the 2-week intervention. Results Shilajit treatment significantly reduced the values of AST and ALT, TG, TC, LDL, glucose, liver weight, and steatosis, and instead, increased high-density lipoprotein (HDL) compared with the vehicle group (p < 0.05). Further, Shilajit treatment improved the adverse effects of HFD-induced histopathological changes in the liver as compared with the vehicle group (p < 0.001). MDA level and GPx activity increased but SOD activity decreased in the vehicle group compared with the control group (p < 0.05), while treatment with Shilajit restored the antioxidant/oxidant balance toward a significant increase in the antioxidant system in the Shilajit group (p < 0.05). Conclusions These findings suggest that Shilajit improved the histopathological NAFLD changes in the liver and indicated the potential applicability of Shilajit as a potent agent for NAFLD treatment.

PREVALENCE OF HEPATIC STEATOSIS AMONG CHILDREN AND ADOLESCENTS WITH CYSTIC FIBROSIS AND ITS ASSOCIATION WITH NUTRITIONAL STATUS

ABSTRACT Objective: To determine the prevalence of hepatic steatosis (HS) in children and adolescents with cystic fibrosis (CF) and associate it with nutritional status. Methods: Cross-sectional study with children and adolescents with CF diagnosis. Weight and height were used to calculate the body mass index (BMI) and subsequent classification of the nutritional status. The midarm circumference (MAC), triceps skinfold thickness (TSF) and midarm muscle circumference (MAMC) were used to evaluate body composition. Abdominal ultrasonography was performed for diagnosis of HS. The statistical tests used were Student’s t test, Mann-Whitney test and chi-square test with significance level of 5%. Results: 50 patients with CF were evaluated, 18 (36%) were diagnosed with HS (Group A) and 32 (64%) without HS (Group B). The mean age of Group A was 13,2±4,9 years old and Group B 11,7±4,9; for BMI, the value for Group A was 18,0±4,1 and Group B was 15,7±3,8; the TSF of Group A was 8,4±3,5 mm and Group B was 7,0±2,5 mm. For these variables, there was no significant difference between the groups. The mean of MAC and MAMC differed significantly between the groups, being higher in the HS group, with p values of 0,047 and 0,043. Conclusions: The frequency of HS in patients with CF is high and it is not related to malnutrition, according to the parameters of BMI, TSF and MAMC. The values of MAC and MAMC indicated a greater reserve of muscle mass in patients with HS.

A Lipidomic Analysis of Docosahexaenoic Acid (22:6, ω3) Mediated Attenuation of Western Diet Induced Nonalcoholic Steatohepatitis in Male Ldlr -/- Mice

Nonalcoholic fatty liver disease (NAFLD) is a major public health problem worldwide. NAFLD ranges in severity from benign steatosis to nonalcoholic steatohepatitis (NASH), cirrhosis, and primary hepatocellular cancer (HCC). Obesity and type 2 diabetes mellitus (T2DM) are strongly associated with NAFLD, and the western diet (WD) is a major contributor to the onset and progression of these chronic diseases. Our aim was to use a lipidomic approach to identify potential lipid mediators of diet-induced NASH. We previously used a preclinical mouse (low density lipoprotein receptor null mouse, Ldlr -/-) model to assess transcriptomic mechanisms linked to WD-induced NASH and docosahexaenoic acid (DHA, 22:6, ω3)-mediated remission of NASH. This report used livers from the previous study to carry out ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) and high-performance liquid chromatography coupled with dynamic multi-reaction monitoring (HPLC-dMRM) to assess the impact of the WD and DHA on hepatic membrane lipid and oxylipin composition, respectively. Feeding mice the WD increased hepatic saturated and monounsaturated fatty acids and arachidonic acid (ARA, 20:4, ω6) in membrane lipids and suppressed ω3 polyunsaturated fatty acids (PUFA) in membrane lipids and ω3 PUFA-derived anti-inflammatory oxylipins. Supplementing the WD with DHA lowered hepatic ARA in membrane lipids and ARA-derived oxylipins and significantly increased hepatic DHA and its metabolites in membrane lipids, as well as C20-22 ω3 PUFA-derived oxylipins. NASH markers of inflammation and fibrosis were inversely associated with hepatic C20-22 ω3 PUFA-derived Cyp2C- and Cyp2J-generated anti-inflammatory oxylipins (false discovery rate adjusted p-value; q ≤ 0.026). Our findings suggest that dietary DHA promoted partial remission of WD-induced NASH, at least in part, by lowering hepatic pro-inflammatory oxylipins derived from ARA and increasing hepatic anti-inflammatory oxylipins derived from C20-22 ω3 PUFA.

Laparoscopic Sleeve Gastrectomy Resolves NAFLD: Another Formal Indication for Bariatric Surgery?

INTRODUCTION

Obesity is strongly associated with non-alcoholic fatty liver disease (NAFLD); 66-99% of the obese population could suffer some grade of NAFLD. It can progress into cirrhosis, which is associated to hepatocellular carcinoma, and a liver transplant could be indicated. NAFLD represents the third cause of liver transplant, and it is expected to be the first by 2025. Sleeve gastrectomy (SG) is the most common bariatric procedure over the world. There is scant literature regarding NAFLD after SG, and there are no prospective studies published up to date.

OBJECTIVE

To evaluate the evolution of NAFLD in patients with obesity after 1 year of SG.

METHODS

From January 2009 to December 2013, intraoperative liver biopsy was performed in 63 obese patients who underwent SG. Forty-three patients were again biopsied 1 year after surgery. Demographics, body mass index, percentage of excess weight loss, liver function test, lipid panel, glucose panel, and histological changes were prospectively analyzed.

RESULTS

One hundred percent of the patients reversed or reduced the stage of steatosis or steatohepatitis 12 months after surgery, obtaining a statistically significant difference for both steatosis and steatohepatitis. One patient presented complete cirrhosis regression in the pathology. Neither of the patients had worsened liver histology.

CONCLUSIONS

NAFLD could be dealt with laparoscopic sleeve gastrectomy, preventing its progression into cirrhosis. SG can be performed in patients with obesity and metabolic syndrome, with NAFLD showing satisfactory results 12 months after surgery. NAFLD should be a formal indication for bariatric surgery.

A microfluidic patterned model of non-alcoholic fatty liver disease: applications to disease progression and zonation

Non-alcoholic fatty liver disease (NAFLD) and its progressive form non-alcoholic steatohepatitis (NASH) affect 25% of the world population. NAFLD is predicted to soon become the main cause of liver morbidity and transplantation. The disease is characterized by a progressive increase of lipid accumulation in hepatocytes, which eventually induce fibrosis and inflammation, and can ultimately cause cirrhosis and hepatic carcinoma. Here, we created a patterned model of NAFLD on a chip using free fatty acid gradients to recapitulate a spectrum of disease conditions in a single continuous liver tissue. We established the NAFLD progression via quantification of intracellular lipid accumulation and transcriptional levels of fatty acid transporters and NAFLD pathogenesis markers. We then used this platform to create oxygen driven steatosis zonation mimicking the sinusoidal lipid distribution on a single continuous tissue and showed that this fat zonation disappears under progressed steatosis, in agreement with in vivo observations and recent computational studies. While we focus on free fatty acids and oxygen as the drivers of NAFLD, the microfluidic platform here is extensible to simultaneous use of other drivers.

Real-world comorbidities and treatment patterns among patients with non-alcoholic fatty liver disease receiving phosphatidylcholine as adjunctive therapy in Russia

Objective

Previous research conducted in Russia showed that the number of patients with non-alcoholic fatty liver disease (NAFLD) and associated metabolic comorbidities is large. We conducted an observational study to describe the management of NAFLD in patients with metabolic syndrome in Russia.

Design

A total of 2843 adult patients from 174 medical sites across 6 federal districts of Russia with newly diagnosed NAFLD, who had at least one of four comorbidities, namely overweight/obesity, hypertension, type 2 diabetes mellitus, and hypercholesterolaemia, and who received phosphatidylcholine (PPC) as an adjunctive treatment to standard care, were enrolled during 2015-2016.

Results

Overall, 2263 patients (79.6%) had at least two metabolic comorbidities associated with NAFLD; overweight/obesity was the most common comorbidity reported in 2298 patients (80.8%). Simple steatosis was the most frequently identified clinical form of NAFLD, diagnosed in 2128 patients (74.9%). Among hypertensive patients, ACE inhibitors, statins, and sartans were most commonly prescribed. Biguanides were administered in more than half of diabetic patients. In patients with overweight/obesity and hypercholesterolaemia, statins were the most frequently prescribed medications. Almost all patients (2837/2843; 99.8%) were treated with 1.8 g of PPC three times per day. PPC therapy was associated with a 90.5% 6-month compliance rate, high treatment satisfaction, and a favourable safety profile. However, almost 15% of diabetic patients and 40% of overweight/obese patients received no further treatment.

Conclusions

In Russia, patients with newly diagnosed NAFLD represent a population heavily burdened by comorbidities, mainly overweight/obesity and hypercholesterolaemia. A significant part of these patients did not receive a comprehensive pharmacotherapy, highlighting the existing unmet need in the current management of NAFLD patients with metabolic syndrome in Russia.

Quantification of steatosis in alcoholic and nonalcoholic fatty liver disease: Evaluation of four MR techniques versus biopsy

PURPOSE

Given the growing prevalence of obesity and metabolic syndrome, the management of hepatic steatosis, especially its quantification, is a major issue. We assessed the quantification of liver steatosis using four different MR methods, in order to determine the one that is best correlated with the reference method which consists of histological measurement by liver biopsy.

METHOD

Seventy-one successive patients requiring liver biopsy for acute or chronic liver disease were enrolled prospectively between March 2017 and March 2018, 11 were excluded and 60 were reported. Liver MR (1.5 T) was organised in order to be performed the same day, using four different steatosis quantification techniques (3-echo MRI, 6-echo MRI, 11-echo MRI and MR Spectroscopy). Quantitative histological and imaging data were compared. In a secondary analysis, we studied the possible influence of alcohol drinking, hepatic iron overload, and the presence of liver fibrosis.

RESULTS

All four MR techniques were found to have excellent correlations with the histological measurements: 3-echo MRI (r = 0.852, p < 0.001), 6-echo MRI (r = 0.819, p < 0.001), 11-echo MRI (r = 0.818, p < 0.001) and MR Spectroscopy (r = 0,812, p < 0,001). Interestingly, we also found that the presence of alcohol consumption, iron overload and fibrosis did not interfere with measurements, whichever technique was used.

CONCLUSION

In the evaluation of hepatic steatosis, our study showed very good correlations of all four MR techniques with the histological standard. There was no confounding factor in a representative group of patients with associated liver conditions such as alcohol consumption, fibrosis and iron overload, for each technique. All four MR techniques may be used in daily practice.