Liver transplantation for nonalcoholic fatty liver disease: New challenges and new opportunities

Implications of Microbiota and Immune System in Development and Progression of Metabolic Dysfunction-Associated Steatotic Liver Disease

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most prevalent type of liver disease worldwide. The exact pathophysiology behind MASLD remains unclear; however, it is thought that a combination of factors or "hits" act as precipitants for disease onset and progression. Abundant evidence supports the roles of diet, genes, metabolic dysregulation, and the intestinal microbiome in influencing the accumulation of lipids in hepatocytes and subsequent progression to inflammation and fibrosis. Currently, there is no cure for MASLD, but lifestyle changes have been the prevailing cornerstones of management. Research is now focusing on the intestinal microbiome as a potential therapeutic target for MASLD, with the spotlight shifting to probiotics, antibiotics, and fecal microbiota transplantation. In this review, we provide an overview of how intestinal microbiota interact with the immune system to contribute to the pathogenesis of MASLD and metabolic dysfunction-associated steatohepatitis (MASH). We also summarize key microbial taxa implicated in the disease and discuss evidence supporting microbial-targeted therapies in its management.

The impact of macro- and micro-steatosis on the outcomes of patients who undergo liver transplant: Analysis of the UNOS-STAR database

BACKGROUND AND AIMS

The presence of steatosis in a donor liver and its relation to post-transplantation outcomes are not well defined. This study evaluates the effect of the presence and severity of micro- and macro-steatosis of a donor graft on post-transplantation outcomes.

METHODS

The UNOS-STAR registry (2005-2019) was used to select patients who received a liver transplant graft with hepatic steatosis. The study cohort was stratified by the presence of macro- or micro-vesicular steatosis, and further stratified by histologic grade of steatosis. The primary endpoints of all-cause mortality and graft failure were compared using sequential Cox regression analysis. Analysis of specific causes of mortality was further performed.

RESULTS

There were 9184 with no macro-steatosis (control), 150 with grade 3 macro-steatosis, 822 with grade 2 macro-steatosis and 12 585 with grade 1 macro-steatosis. There were 10 320 without micro-steatosis (control), 478 with grade 3 micro-steatosis, 1539 with grade 2 micro-steatosis and 10 404 with grade 1 micro-steatosis. There was no significant difference in all-cause mortality or graft failure among recipients who received a donor organ with any evidence of macro- or micro-steatosis, compared to those receiving non-steatotic grafts. There was increased mortality due to cardiac arrest among recipients of a grade 2 macro-steatosis donor organ.

CONCLUSION

This study shows no significant difference in all-cause mortality or graft failure among recipients who received a donor liver with any degree of micro- or macro-steatosis. Further analysis identified increased mortality due to specific aetiologies among recipients receiving donor organs with varying grades of macro- and micro-steatosis.

Effectiveness of metformin for the reversal of cold-ischemia-induced damage in hepatosteatosis

BACKGROUND

Primary dysfunction and rejection are more common in donor liver tissues with steatosis. AMP-activated protein kinase (AMPK) assumes organ-protective functions during ischemia. Metformin was used for the activation of AMPK in hepatocytes. The aim of this study is to investigate the effectiveness of metformin administration for the reversal of cold-ischemia-induced damage in hepatosteatosis.

MATERIAL AND METHODS

Seven-week-old C7BL56 male-mice (n = 109) were separated into four groups depending on diet type and metformin use. A specific diet model was followed for 10 weeks to induce hepatosteatosis. A group of the animals was administered with metformin for the last four weeks via oral gavage. After resection, the liver tissues were perfused and kept for 0-6-12-24 h in the UW solution. Histopathological examinations were performed, and Western blot was utilized to analyze p-AMPK and AMPK expression levels.

RESULTS

Hepatosteatosis decreased significantly with metformin. The steatotic liver group had more prominent pericentral inflammation, necrosis as well as showing a decreased and more delayed AMPK response than the non-fat group. All these alterations could be corrected using metformin.

CONCLUSION

Metformin can increase the resistance of livers with hepatosteatosis to cold-ischemia-induced damage, which in turn may pave the way for successful transplantation of fatty living-donor livers.

Multi-omics analysis of a fatty liver model using human hepatocyte chimeric mice

We developed a fatty liver mouse model using human hepatocyte chimeric mice. As transplanted human hepatocytes do not respond to mouse growth hormone (GH) and tend to accumulate fat, we hypothesized that addition of human GH would alter lipid metabolism and reduce accumulation of fat in the liver even when fed a high-fat diet. Six uPA/SCID chimeric mice were fed a high-fat GAN diet to induce fatty liver while six were fed a normal CRF1 diet, and GH was administered to three mice in each group. The mice were euthanized at 8 weeks, and human hepatocytes were extracted for RNA-Seq, DIA proteomics, and metabolomics analysis. Abdominal echocardiography revealed that the degree of fatty liver increased significantly in mice fed GAN diet (p < 0.001) and decreased significantly in mice treated with GH (p = 0.026). Weighted gene correlation network analysis identified IGF1 and SEMA7A as eigengenes. Administration of GH significantly reduced triglyceride levels and was strongly associated with metabolism of amino acids. MiBiOmics analysis identified perilipin-2 as a co-inertia driver. Results from multi-omics analysis revealed distinct gene expression and protein/metabolite profiles in each treatment group when mice were fed a high-fat or normal diet with or without administration of GH.

Circumventricular organ-hypothalamic circuit endoplasmic reticulum stress drives hepatic steatosis during obesity

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD), characterized by excess liver triglyceride accumulation (hepatic steatosis), leads to an increased risk for cardiometabolic diseases and obesity-related mortality. Emerging evidence points to endoplasmic reticulum (ER) stress in the central nervous system as critical in NAFLD pathogenesis. Here, we tested the contribution of ER stress in a circumventricular organ-hypothalamic circuit in NAFLD development during obesity.

METHODS

C57BL/6J male mice were fed a high-fat diet (HFD) or normal chow. A combination of histological, viral tracing, intersectional viral targeting, and in vivo integrative physiological approaches were used to examine the role of ER stress in subfornical organ to hypothalamic paraventricular nucleus projecting neurons (SFO➔PVN) in NAFLD during diet-induced obesity.

RESULTS

Immunohistochemical analysis revealed marked unfolded protein response activation in the SFO, particularly in excitatory SFO➔PVN neurons of HFD-fed animals. Moreover, intersectional viral inhibition of ER stress in SFO➔PVN neurons resulted in a reduction in hepatomegaly, hepatic steatosis, and a blunted increase in body weight gain during diet-induced obesity, independent of changes in food intake, substrate partitioning, energy expenditure, and ambulatory activity.

CONCLUSIONS

These results indicate that ER stress in an SFO➔PVN neural circuit contributes to hepatic steatosis during obesity.

Antifibrotic therapy in nonalcoholic steatohepatitis: time for a human-centric approach

Nonalcoholic steatohepatitis (NASH) might soon become the leading cause of end-stage liver disease and indication for liver transplantation worldwide. Fibrosis severity is the only histological predictor of liver-related morbidity and mortality in NASH identified to date. Moreover, fibrosis regression is associated with improved clinical outcomes. However, despite numerous clinical trials of plausible drug candidates, an approved antifibrotic therapy remains elusive. Increased understanding of NASH susceptibility and pathogenesis, emerging human multiomics profiling, integration of electronic health record data and modern pharmacology techniques hold enormous promise in delivering a paradigm shift in antifibrotic drug development in NASH. There is a strong rationale for drug combinations to boost efficacy, and precision medicine strategies targeting key genetic modifiers of NASH are emerging. In this Perspective, we discuss why antifibrotic effects observed in NASH pharmacotherapy trials have been underwhelming and outline potential approaches to improve the likelihood of future clinical success.

Screening, Diagnosis, and Staging of Non-Alcoholic Fatty Liver Disease (NAFLD): Application of Society Guidelines to Clinical Practice

PURPOSE OF REVIEW

Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly nonalcoholic fatty liver disease (NAFLD), is the most common chronic liver disease affecting 30% of the global population. In this article, we summarize current expert guidelines, review clinical practice implications, and provide insight into the utility of non-invasive tests (NITs).

RECENT FINDINGS

The burden of MASLD is growing with the obesity epidemic, yet disease awareness and diagnosis is low. Patients can progress to metabolic dysfunction-associated steatohepatitis (MASH, formerly NASH), which can advance to liver fibrosis, cirrhosis, hepatic decompensation, and liver cancer. NITs help identify high-risk patients who may benefit from specialty referral and MASH-directed therapy. Global societies offer various recommendations for the screening and diagnosis of MASLD utilizing evidence-based, widely accessible methods such as serum indices, NITs, and liver biopsy. Several targeted steatotic liver disease (SLD) screening tools and novel therapies are under development.

Ethnic differences in hepatocellular carcinoma prevalence and therapeutic outcomes

BACKGROUND

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death worldwide. The incidence of HCC is affected by genetic and non-genetic factors. Genetically, mutations in the genes, tumor protein P53 (TP53), catenin beta 1 (CTNNB1), AT-rich interaction domain 1A (ARIC1A), cyclin dependent kinase inhibitor 2A (CDKN2A), mannose 6-phosphate (M6P), smooth muscle action against decapentaplegic (SMAD2), retinoblastoma gene (RB1), cyclin D, antigen presenting cells (APC), AXIN1, and E-cadherin, have been shown to contribute to the occurrence of HCC. Non-genetic factors, including alcohol consumption, exposure to aflatoxin, age, gender, presence of hepatitis B (HBV), hepatitis C (HCV), and non-alcoholic fatty liver disease (NAFLD), increase the risk of HCC.

RECENT FINDINGS

The severity of the disease and its occurrence vary based on geographical location. Furthermore, men and minorities have been shown to be disproportionately affected by HCC, compared with women and non-minorities. Ethnicity has been reported to significantly affect tumorigenesis and clinical outcomes in patients diagnosed with HCC. Generally, differences in gene expression and/or the presence of comorbid medical diseases affect or influence the progression of HCC. Non-Caucasian HCC patients are significantly more likely to have poorer survival outcomes, compared to their Caucasian counterparts. Finally, there are a number of factors that contribute to the success rate of treatments for HCC.

CONCLUSION

Assessment and treatment of HCC must be consistent using evidence-based guidelines and standardized outcomes, as well as international clinical practice guidelines for global consensus. Standardizing the assessment approach and method will enable comparison and improvement of liver cancer research through collaboration between researchers, healthcare providers, and advocacy groups. In this review, we will focus on discussing epidemiological factors that result in deviations and changes in treatment approaches for HCC.

You Are What You Eat: A Review on Dietary Interventions for Treating Pediatric Nonalcoholic Fatty Liver Disease

As the obesity pandemic worsens, cases of pediatric nonalcoholic fatty liver disease (NAFLD) and complications of this disease, such as progressive liver failure, in young adults will continue to rise. Lifestyle changes in the form of dietary modifications and exercise are currently first-line treatments. Large pediatric-specific randomized controlled trials to support specific interventions are currently lacking. A variety of dietary modifications in children with NAFLD have been suggested and studied with mixed results, including low-sugar and high-protein diets, the Mediterranean diet, and the Dietary Approach to Stop Hypertension (DASH). The roles of dietary supplements such as Vitamin E, polyunsaturated fatty acids (PUFAs), ginger, and probiotics have also been investigated. A further understanding of specific dietary interventions and supplements is needed to provide both generalizable and sustainable dietary recommendations to reverse the progression of NAFLD in the pediatric population.

Targeted MicroRNA Profiling Reveals That Exendin-4 Modulates the Expression of Several MicroRNAs to Reduce Steatosis in HepG2 Cells

Excess hepatic lipid accumulation is the hallmark of non-alcoholic fatty liver disease (NAFLD), for which no medication is currently approved. However, glucagon-like peptide-1 receptor agonists (GLP-1RAs), already approved for treating type 2 diabetes, have lately emerged as possible treatments. Herein we aim to investigate how the GLP-1RA exendin-4 (Ex-4) affects the microRNA (miRNAs) expression profile using an in vitro model of steatosis. Total RNA, including miRNAs, was isolated from control, steatotic, and Ex-4-treated steatotic cells and used for probing a panel of 799 highly curated miRNAs using NanoString technology. Enrichment pathway analysis was used to find the signaling pathways and cellular functions associated with the differentially expressed miRNAs. Our data shows that Ex-4 reversed the expression of a set of miRNAs. Functional enrichment analysis highlighted many relevant signaling pathways and cellular functions enriched in the differentially expressed miRNAs, including hepatic fibrosis, insulin receptor, PPAR, Wnt/β-Catenin, VEGF, and mTOR receptor signaling pathways, fibrosis of the liver, cirrhosis of the liver, proliferation of hepatic stellate cells, diabetes mellitus, glucose metabolism disorder and proliferation of liver cells. Our findings suggest that miRNAs may play essential roles in the processes driving steatosis reduction in response to GLP-1R agonists, which warrants further functional investigation.

Should responsibility be used as a tiebreaker in allocation of deceased donor organs for patients suffering from alcohol-related end-stage liver disease?

There is a long-standing debate concerning the eligibility of patients suffering from alcohol-related end-stage liver disease (ARESLD) for deceased donor liver transplantation. The question of retrospective and/or prospective responsibility has been at the center of the ethical discussion. Several authors argue that these patients should at least be regarded as partly responsible for their ARESLD. At the same time, the arguments for retrospective and/or prospective responsibility have been strongly criticized, such that no consensus has been reached. A third option was proposed as a form of compromise, namely that responsibility should only be used as a tiebreaker in liver allocation. The present study provides an ethical investigation of this third option. First, we will provide an overview of the main arguments that have been offered for and against the use of responsibility as an allocation criterion. Second, we will explore the concept of responsibility as a tiebreaker in detail and discuss several types of situations, in which responsibility could be used as a tiebreaker, as well as the main ethical challenges associated with them. As we will show, an ethical justified use of responsibility as a tiebreaker is limited to a very restricted number of cases and is associated with a number of ethical concerns. For this reason, waiting time should be preferred as a tiebreaker in liver allocation, even though the criterion of waiting time, too, raises a number of equity-related concerns.

Dietary selenium intake in relation to non-alcoholic fatty liver disease assessed by fatty liver index and hepatic steatosis index; a cross-sectional study on the baseline data of prospective PERSIAN Kavar cohort study

BACKGROUND

There is limited and conflicting evidence on the association between selenium and non-alcoholic fatty liver disease (NAFLD). Therefore, the present population-based cross-sectional study aimed to explore the relationship between dietary selenium intake and the risk of NAFLD.

METHODS

A total of 3026 subjects from the PERSIAN (Prospective Epidemiological Research Studies in IrAN) Kavar cohort study were included in the analysis. The daily selenium intake was evaluated using a semi-quantitative food frequency questionnaire, and energy-adjusted quintiles of selenium intake (µg/day) were calculated. NAFLD was defined as the fatty liver index (FLI) ≥ 60 or the hepatic steatosis index (HSI) > 36. The association between dietary selenium intake and NAFLD was evaluated using logistic regression analysis.

RESULTS

The prevalence rates of NAFLD were 56.4% and 51.9%, based on the FLI and HSI markers, respectively. The odds ratios (ORs) for FLI-defined NAFLD were 1.31 (95% confidence interval (CI): 1.01-1.70) and 1.50 (95% CI: 1.13-1.99) for the fourth and fifth quintiles of selenium intake, respectively, after adjustment for sociodemographic variables, smoking status, alcohol drinking, physical activity, and dietary factors (P trend = 0.002). There was also a similar association between selenium intakes and HSI-defined NAFLD (OR = 1.34 (95% CI: 1.03-1.75) for the fourth quintile and OR = 1.50 (95% CI: 1.12-2.01) for the fifth quintile of selenium intake) (P trend = 0.006).

CONCLUSION

In this large sample study, we observed a weak positive association between dietary selenium intake and NAFLD risk.

Management and Risks Before, During, and After Liver Transplant in Individuals With Obesity

Obesity has become a global epidemic, adding to the burden of chronic diseases and disabilities. Metabolic syndrome, especially obesity, is a significant risk factor for nonalcoholic fatty liver disease, which is the most common indication for liver transplant (LT). The prevalence of obesity among the LT population is growing. Obesity increases the necessity of LT by playing a role in the development of nonalcoholic fatty liver disease, decompensated cirrhosis, and hepatocellular carcinoma, and it can also coexist with other diseases requiring LT. Therefore, LT teams must identify key aspects required to manage this high-risk population, but there are currently no defined recommendations for managing obesity in LT candidates. Although body mass index is often used to assess the weight of patients and classify them as overweight or obese, this measure may be inaccurate to use in patients with decompensated cirrhosis, as fluid overload or ascites can significantly add to the weight of patients. Diet and exercise remain the cornerstone of obesity management. Supervised weight loss before LT, without worsening frailty and sarcopenia, may be beneficial in reducing surgical risks and improving long-term LT outcomes. Bariatric surgery is another effective treatment for obesity, with sleeve gastrectomy currently conferring the best outcomes in LT recipients. However, evidence supporting the timing of bariatric surgery is lacking. Long-term patient and graft survival data in individuals with obesity following LT are scarce. Class 3 obesity (body mass index ≥40) further complicates the treatment of this patient population. This article discusses the impact of obesity on the outcome of LT.

Relationship between the Mediterranean diet and risk of hepatic fibrosis in patients with non-alcoholic fatty liver disease: A cross-sectional analysis of the RaNCD cohort

Background

Despite evidence supporting the beneficial effects of the Mediterranean diet (MedDiet) on hepatic steatosis in subjects with non-alcoholic fatty liver disease (NAFLD), the relationship of the MedDiet with hepatic fibrosis is as yet unclear. The aim of the present study was to explore this association in Iranian adults with NAFLD.

Methods

This cross-sectional study included 3,325 subjects with NAFLD from the Ravansar Noncommunicable Disease (RaNCD) cohort. Dietary intake data were collected by a validated food frequency questionnaire (FFQ). The MedDiet score was computed based on a nine-point scale constructed by Trichopoulou et al. Fatty liver index (FLI) and fibrosis-4 (FIB-4) index were used to predict hepatic steatosis and fibrosis in the population. Multivariate regression models were applied to determine associations.

Results

Subjects in the highest tertile of MedDiet score had a higher platelet and a lower weight, total cholesterol (TC), LDL-c, and FLI than those in the lowest tertile (p-value < 0.05). Adherence to the MedDiet was associated with a 7.48 (95%CI: 5.376 to 9.603; p-value: 0.001) × 10³/μl; -0.417 (95%CI: -0.819 to -0.014; p-value: 0.042) kg, -2.505 (95%CI: -3.835 to -1.175; p-value: 0.001) mg/dl; and -1.93 (95%CI: -2.803 to -1.061; p-value: 0.001) mg/dl change in platelet, weight, TC, and LDL-c for each SD increase in the score, respectively. A significant linear trend was observed in odds of hepatic fibrosis across the tertiles of the MedDiet score (P-trend: 0.008). This linear trend was attenuated but remained significant after the adjustment of the relevant confounders (P-trend: 0.032). Adherence to the MedDiet was independently associated with about 16% lower odds of having hepatic fibrosis in patients with NAFLD for each SD increase in the score.

Conclusion

Adherence to the MedDiet characterized by a high intake of whole grains, fruits, vegetables, legumes, nuts, and fish was associated with a lower risk of having hepatic fibrosis in patients with NAFLD. Further studies are required to elucidate the causal relationship of observed association in individuals of all ages, ethnicities, and etiologies of hepatic steatosis.

Growing challenge of post-liver transplantation non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is one of the leading causes of chronic liver disease, cirrhosis, and hepatocellular carcinoma worldwide, with an estimated prevalence of 25%. Post-liver transplantation (LT) recurrent or de novo hepatic steatosis is a common complication in recipients, irrespective of transplantation indication. Risk factors for graft steatosis mainly include obesity, immunosuppression, donor steatosis, and genetic factors. Liver transplant recipients are at high risk of developing insulin resistance, new-onset diabetes, and post-transplantation metabolic syndrome that is highly associated with immunosuppressive treatment. Post-LT NAFLD is often underdiagnosed due to the poor sensitivity of most routine imaging methods. The gold standard for the diagnosis of hepatic steatosis is liver biopsy, which is, however, limited to more complex cases due to its invasive nature. There is no approved pharmacotherapy in NAFLD. Lifestyle modification remains the cornerstone in NAFLD treatment. Other treatment strategies in post-LT NAFLD include lifestyle modifications, pharmacotherapy, bariatric surgery, and tailored immunosuppression. However, these approaches originate from recommendations in the general population, as there is scarce data regarding the safety and efficacy of current management strategies for NAFLD in liver transplant patients. Future prospective studies are required to achieve tailored treatment for these patients.

Preparedness of Residents to Manage Pediatric Nonalcoholic Fatty Liver Disease: A National Survey

Objective

Non-Alcoholic Fatty Liver Disease (NAFLD) is reported to be the most common chronic pediatric liver disease. Little information is available on the adherence of residents in-training to the published guidelines for the evaluation and management of pediatric NAFLD.The goals of this study are: (i) to assess the consistency of screening and evaluation for NAFLD in obese and overweight children at continuity clinics by upper level residents, and (ii) to determine the residents' extent of training, knowledge, comfort and competence levels in NAFLD care.

Methods

An electronic survey developed using REDCap was emailed to accredited Pediatric Residency Programs in the United States. Program directors and coordinators were requested to forward the survey to their upper level pediatric and medicine/pediatrics residents. Statistical analysis of responses (n= 399) was performed.

Results

More than 88% of residents reported to be exposed to obese and overweight children, representing at least 25% of the patients encountered in clinics. Regardless of their training level, they inconsistently screened for (>60%), initiated evaluation of, or provided counseling on NAFLD in these patients, not following the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition guidelines. Over 80% of residents perceived to have received inadequate training resulting in insufficient knowledge on NAFLD, which they identified as their biggest barrier (25.7%). There was minimal statistically significant difference in the survey findings between training levels (PGY-2 vs PGY-3/4).

Conclusions

Educational interventions should be implemented by pediatric residency programs to enhance educational core curricula for the early detection and initiation of management of NAFLD, an emerging public health problem.

Non-alcoholic fatty liver disease and the impact of genetic, epigenetic and environmental factors in the offspring

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide and is strongly associated with metabolic deregulation. More recently, a significant impact of parental NAFLD in the offspring was demonstrated and has been widely discussed. However, pathogenetic pathways implicated in the inheritance by the offspring and relatives are still under debate. Probably, multiple mechanisms are involved as well as in NAFLD pathogenesis itself. Among the multifactorial involved mechanisms, genetic, epigenetic and environmental backgrounds are strongly related to NAFLD development in the offspring. Thus, based on recent evidence from the available literature concerning genetic, epigenetic and environmental disease modifiers, this review aimed to discuss the relationship between parental NAFLD and its impact on the offspring.

Nonalcoholic Fatty Liver Disease and Associated Risk Factors in a Community-Based Sample of Mexican-Origin Adults

The incidence of nonalcoholic fatty liver disease (NAFLD) is highest among Mexican-origin (MO) adults. Few studies have estimated the prevalence of NAFLD in this subpopulation, particularly by sex and age. We assessed the prevalence of NAFLD in a community sample of MO adults residing in a border region of southern Arizona and determined risk factors associated with NAFLD. A total of 307 MO adults (n = 194 women; n = 113 men) with overweight or obesity completed an in-person study visit, including vibration-controlled transient elastography (FibroScan) for the assessment of NAFLD status. A continuous attenuation parameter score of ≥288 dB/m (≥5% hepatic steatosis) indicated NAFLD status. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for NAFLD. We identified 155 participants (50%) with NAFLD, including 52% of women and 48% of men; there were no sex differences in steatosis (men, 287.8 dB/m; women, 288.4 dB/m). Sex, age, patatin-like phospholipase domain containing 3 (PNPLA3) risk allele carrier status, comorbidities, and cultural and behavioral variables were not associated with NAFLD status. There was some evidence for effect modification of body mass index (BMI) by sex (Pinteraction  = 0.08). The estimated OR for an increase in BMI of 5 kg/m2 was 3.36 (95% CI, 1.90, 5.91) for men and 1.92 (95% CI, 1.40, 2.64) for women. In post hoc analyses treating steatosis as a continuous variable in a linear regression, significant effect modification was found for BMI by sex (Pinteraction  = 0.03), age (P = 0.05), and PNPLA3 risk allele carrier status (P = 0.02). Conclusion: Lifestyle interventions to reduce body weight, with consideration of age and genetic risk status, are needed to stem the higher rates of NAFLD observed for MO populations.

The Main Thing is to be Alive-Exploring Patients' Experiences With Weight Gain After Liver Transplantation: A Qualitative Study

Weight gain after liver transplantation (LTx) contributes to new-onset obesity. We explored patients’ experiences with gaining weight after LTx. Individual interviews were guided by open-ended questions. We analyzed transcripts with the reflexive thematic analysis approach by Braun and Clarke. The 12 participants gained 11.5 kg weight (median) over a median of 23 months after LTx. The constitutive theme “The main thing is to be alive” was a recurrent insight, captured in three facets: “The arduous path back to living” was the emotional expression of the ups and downs during a life-threatening illness to finally being grateful for the new life. “A pleasurable new phase of life” was the legitimation, reflecting the appreciation of gaining weight and returning to a healthy appearance. “I am allowed to look like this now” was the consoling facet after a time of burden due to the increased weight and frustration of being unsuccessful in losing weight. Finally, the awareness of being a LTx survivor outplayed the burden of the excess weight. Early interventions are crucial because the comforting insight “I am allowed to look like this now” may hinder further engagement in weight loss activities. Our recommendations on education and self-management support may guide clinical practice.

Quality More Than Quantity: The Use of Carbohydrates in High-Fat Diets to Tackle Obesity in Growing Rats

Childhood obesity prevention is important to avoid obesity and its comorbidities into adulthood. Although the energy density of food has been considered a main obesogenic factor, a focus on food quality rather that the quantity of the different macronutrients is needed. Therefore, this study investigates the effects of changing the quality of carbohydrates from rapidly to slowly digestible carbohydrates on metabolic abnormalities and its impact on obesity in growing rats fed a high-fat diet (HFD). Growing rats were fed on HFD containing carbohydrates with different digestion rates: a HFD containing rapid-digesting carbohydrates (OBE group) or slow-digesting carbohydrates (ISR group), for 4 weeks and the effect on the metabolism and signaling pathways were analyzed in different tissues. Animals from OBE group presented an overweight/obese phenotype with a higher body weight gain and greater accumulation of fat in adipose tissue and liver. This state was associated with an increase of HOMA index, serum diacylglycerols and triacylglycerides, insulin, leptin, and pro-inflammatory cytokines. In contrast, the change of carbohydrate profile in the diet to one based on slow digestible prevented the obesity-related adverse effects. In adipose tissue, GLUT4 was increased and UCPs and PPARγ were decreased in ISR group respect to OBE group. In liver, GLUT2, FAS, and SRBP1 were lower in ISR group than OBE group. In muscle, an increase of glycogen, GLUT4, AMPK, and Akt were observed in comparison to OBE group. In conclusion, this study demonstrates that the replacement of rapidly digestible carbohydrates for slowly digestible carbohydrates within a high-fat diet promoted a protective effect against the development of obesity and its associated comorbidities.

Differential progression of unhealthy diet-induced hepatocellular carcinoma in obese and non-obese mice

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) ranks first among liver diseases in Western countries. NAFLD is typically associated with obesity and diabetes, however it also develops in lean individuals without metabolic syndrome. The prevalence of lean NAFLD is 7 percent in the U.S. and 25-30 percent in some Asian countries. NAFLD starts with excess liver fat accumulation (NAFL), progresses to nonalcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma (HCC). The pathogenesis of lean NASH-HCC and how it differs from obese NASH-HCC is not well understood.

METHODS

In this work, we generated a mouse model of lean and obese NASH-HCC using a choline deficient/high trans-fat/fructose/cholesterol diet and a choline supplemented/high trans-fat/fructose/cholesterol diet, respectively, to compare progression to NASH-HCC in lean versus obese mice. Comparisons were made at the organismal, histological, and molecular level by investigating fatty acid metabolism in the plasma of these mice.

RESULTS

Obese mice showed more pronounced glucose intolerance and insulin resistance, higher levels of plasma cholesterol and triglycerides, and higher penetrance of NASH compared to lean mice. Despite the abnormal metabolic profile of obese mice, male obese and lean mice developed HCC with similar penetrance (53.3% and 53.8%, respectively), albeit lean mice showed faster tumor progression as evidenced by the larger tumor size and lower HCC-free survival. None of the female lean mice developed HCC, while 50% of female obese mice developed HCC. Both groups of mice showed a reduction in plasma polyunsaturated fatty acids (PUFAs), however, the levels were higher towards the endpoint in obese mice compared to lean mice.

CONCLUSIONS

Unhealthy diet composition appears to drive progression to NASH-HCC rather than the organismal effects of obesity. PUFA levels may increase due to systemic inflammation in obese mice and act as suppressors of tumor progression, thus delaying HCC progression in obese mice compared to lean mice. These models could be used to further dissect the molecular pathogenesis of lean and obese NASH-HCC and address the mechanisms whereby PUFAs may be implicated in hepatocarcinogenesis.

The Role of Physical Activity in Nonalcoholic and Metabolic Dysfunction Associated Fatty Liver Disease

Sedentary behavior constitutes a pandemic health threat contributing to the pathophysiology of obesity and type 2 diabetes (T2D). Sedentarism is further associated with liver disease and particularly with nonalcoholic/metabolic dysfunction associated fatty liver disease (NAFLD/MAFLD). Insulin resistance (IR) represents an early pathophysiologic key element of NAFLD/MAFLD, prediabetes and T2D. Current treatment guidelines recommend regular physical activity. There is evidence, that physical exercise has impact on a variety of molecular pathways, such as AMP-activated protein kinase and insulin signaling as well as glucose transporter 4 translocation, modulating insulin action, cellular substrate flow and in particular ectopic lipid and glycogen storage in a positive manner. Therefore, physical exercise can lead to substantial clinical benefit in persons with diabetes and/or NAFLD/MAFLD. However, experience from long term observational studies shows that the patients’ motivation to exercise regularly appears to be a major limitation. Strategies to integrate everyday physical activity (i.e., nonexercise activity thermogenesis) in lifestyle treatment schedules might be a promising approach. This review aggregates evidence on the impact of regular physical activity on selected molecular mechanisms as well as clinical outcomes of patients suffering from IR and NAFLD/MAFLD.

Single-cell RNA transcriptome landscape of hepatocytes and non-parenchymal cells in healthy and NAFLD mouse liver

Nonalcoholic fatty liver disease (NAFLD) is a global health-care problem with limited therapeutic options. To obtain a cellular resolution of pathogenesis, 82,168 single-cell transcriptomes (scRNA-seq) across different NAFLD stages were profiled, identifying hepatocytes and 12 other non-parenchymal cell (NPC) types. scRNA-seq revealed insights into the cellular and molecular mechanisms of the disease. We discovered a dual role for hepatic stellate cells in gene expression regulation and in the potential to trans-differentiate into myofibroblasts. We uncovered distinct expression profiles of Kupffer cells versus monocyte-derived macrophages during NAFLD progression. Kupffer cells showed stronger immune responses, while monocyte-derived macrophages demonstrated a capability for differentiation. Three chimeric NPCs were identified including endothelial-chimeric stellate cells, hepatocyte-chimeric endothelial cells, and endothelial-chimeric Kupffer cells. Our work identified unanticipated aspects of mouse with NAFLD at the single-cell level and advanced the understanding of cellular heterogeneity in NAFLD livers.

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Of all, 82,168 single-cell transcriptomes across different NAFLD stages were profiled

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Hepatocytes and 12 non-parenchymal cell types were identified in mouse liver

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Three chimeric NPCs were identified in mouse liver

Hypothermic oxygenated perfusion with defatting cocktail further improves steatotic liver grafts in a transplantation rat model

In this study, we evaluated the restoring and defatting effect of hypothermic oxygenated perfusion (HOPE) on severe steatotic liver grafts with a defatting cocktail (DF) in a rat model. Severe (≥60%) hepatic macrosteatosis was induced by a high-fat diet (HFD) for 6 weeks, after which the rats were randomly divided into four following groups: Control group, with lean livers being preserved in static cold storage (SCS) at 0°C-4°C for 45 minutes; SCS group, with a steatotic liver graft (SLG) being preserved in SCS at 0°C-4°C for 4 hours; HOPE group, where SLG was perfused with 3-hours HOPE followed by 1-hours SCS; and HOPE + DF group, HOPE with the addition of DF. Graft function after orthotopic liver transplantation was assessed in terms of mitochondrial function (adenosine triphosphate [ATP], Glycogen), endoplasmic reticulum stress (PPY, GRP78, CHOP, and ATF-6), cell apoptosis (Tunel assay, Caspase-3), inflammatory level (HMGB1, TLR4, IL-1β, IL-6. TNF-α, Factor V), and posttransplantation survival. HOPE protected steatotic liver grafts from microcirculation disturbance and endoplasmic reticulum stress and then promoted ATP and glycogen synthesis that improved mitochondrial function. Meanwhile, under conditions of ischemia-reperfusion injury, it prevented nuclear injury and endothelial damage by suppressing the release of an inflammatory mediator. The high efficacy of HOPE was enhanced after the addition of the DF. DF agents cannot promote the lipid decomposition of the steatotic liver graft at 0°C-4°C, but they can further improve steatotic liver and postoperative survival compared to the HOPE. The defatted steatotic liver grafts can be safely used in rat orthotopic liver transplantation.

Factors associated with engagement and adherence to a low-energy diet to promote 10% weight loss in patients with clinically significant non-alcoholic fatty liver disease

Objective

Clinical guidelines recommend weight loss to manage non-alcoholic fatty liver disease (NAFLD). However, the majority of patients find weight loss a significant challenge. We identified factors associated with engagement and adherence to a low-energy diet (LED) as a treatment option for NAFLD.

Design

23 patients with NAFLD enrolled in a LED (~800 kcal/day) were individually interviewed. Transcripts were thematically analysed.

Results

14/23 patients achieved ≥10% weight loss, 18/23 achieved ≥7% weight loss and 19/23 achieved ≥5% weight loss. Six themes were generated from the data. A desire to achieve rapid weight loss to improve liver health and prevent disease progression was the most salient facilitator to engagement. Early and significant weight loss, accountability to clinicians and regular appointments with personalised feedback were facilitators to engagement and adherence. The desire to receive positive reinforcement from a consultant was a frequently reported facilitator to adherence. Practical and emotional support from friends and family members was critically important outside of the clinical setting. Irregular working patterns preventing attendance at appointments was a barrier to adherence and completion of the intervention.

Conclusions

Engagement and adherence to a LED in patients with NAFLD were encouraged by early and rapid weight loss, personalised feedback and positive reinforcement in the clinical setting combined with ongoing support from friends and family members. Findings support those identified in patients who completed a LED to achieve type 2 diabetes remission and highlight the importance of behaviour change support during the early stages of a LED to promote adherence.

Feasibility of a Very Low Calorie Diet to Achieve a Sustainable 10% Weight Loss in Patients With Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is the most common liver condition worldwide. A weight loss goal of ≥10% is the recommended treatment for NAFLD; however, only a minority of patients achieve this level of weight reduction with standard dietary approaches. This study aimed to determine whether a very low calorie diet (VLCD) is an acceptable and feasible therapy to achieve and maintain a ≥10% weight loss in patients with clinically significant NAFLD.

Lack of Multidrug Resistance-associated Protein 4 Prolongs Partial Hepatectomy-induced Hepatic Steatosis

Multidrug resistance-associated protein 4 (Mrp4) is an efflux transporter involved in the active transport of several endogenous and exogenous chemicals. Previously, we have shown that hepatic Mrp4 expression increases following acetaminophen overdose. In mice, these increases in Mrp4 expression are observed specifically in hepatocytes undergoing active proliferation. From this, we hypothesized that Mrp4 plays a key role in hepatocyte proliferation and that lack of Mrp4 impedes liver regeneration following liver injury and/or tissue loss. To evaluate the role of Mrp4 in these processes, we employed two-third partial hepatectomy (PH) as an experimental liver regeneration model. In this study, we performed PH-surgery on male wildtype (C57BL/6J) and Mrp4 knockout mice. Plasma and liver tissues were collected at 24, 48, and 72 h postsurgery and evaluated for liver injury and liver regeneration endpoints, and for PH-induced hepatic lipid accumulation. Our results show that lack of Mrp4 did not alter hepatocyte proliferation and liver injury following PH as evaluated by Ki-67 antigen staining and plasma alanine aminotransferase levels. To our surprise, Mrp4 knockout mice exhibited increased hepatic lipid content, in particular, di- and triglyceride levels. Gene expression analysis showed that lack of Mrp4 upregulated hepatic lipin1 and diacylglycerol O-acyltransferase 1 and 2 gene expression, which are involved in the synthesis of di- and triglycerides. Our observations indicate that lack of Mrp4 prolonged PH-induced hepatic steatosis in mice and suggest that Mrp4 may be a novel genetic factor in the development of hepatic steatosis.

Insights into the Impact of Microbiota in the Treatment of NAFLD/NASH and Its Potential as a Biomarker for Prognosis and Diagnosis

Non-alcoholic fatty liver disease (NAFLD) is an increasing cause of chronic liver illness associated with obesity and metabolic disorders, such as hypertension, dyslipidemia, or type 2 diabetes mellitus. A more severe type of NAFLD, non-alcoholic steatohepatitis (NASH), is considered an ongoing global health threat and dramatically increases the risks of cirrhosis, liver failure, and hepatocellular carcinoma. Several reports have demonstrated that liver steatosis is associated with the elevation of certain clinical and biochemical markers but with low predictive potential. In addition, current imaging methods are inaccurate and inadequate for quantification of liver steatosis and do not distinguish clearly between the microvesicular and the macrovesicular types. On the other hand, an unhealthy status usually presents an altered gut microbiota, associated with the loss of its functions. Indeed, NAFLD pathophysiology has been linked to lower microbial diversity and a weakened intestinal barrier, exposing the host to bacterial components and stimulating pathways of immune defense and inflammation via toll-like receptor signaling. Moreover, this activation of inflammation in hepatocytes induces progression from simple steatosis to NASH. In the present review, we aim to: (a) summarize studies on both human and animals addressed to determine the impact of alterations in gut microbiota in NASH; (b) evaluate the potential role of such alterations as biomarkers for prognosis and diagnosis of this disorder; and (c) discuss the involvement of microbiota in the current treatment for NAFLD/NASH (i.e., bariatric surgery, physical exercise and lifestyle, diet, probiotics and prebiotics, and fecal microbiota transplantation).

Double-lobectomy in a steatotic liver transplantation rat model

Establishing a steatotic liver transplantation animal model can be a challenging process, which requires complex microsurgical technologies. The present study established a novel rat model of stable steatotic liver transplantation for marginal liver graft research, which notably minimized the number of animals used for the experiment. Briefly, male Sprague-Dawley rats (n=90) were fed with a high-fat diet (HFD; 60%, kJ) or standard chow diet (SCD) for 8 weeks. The liver enzymes and lipid levels were assessed every week, and the degree of steatosis was determined via hematoxylin and eosin and Oil Red O staining. The results demonstrated that there were no significant differences in alanine aminotransaminase and aspartate aminotransferase levels between the SCD and HFD groups (P>0.05), whereas the level of plasma triglyceride (TG) increased by 1.76-fold in the HFD group at week 2, and progressively decreased to baseline levels by week 8. Significantly higher levels of TG were observed in the HFD group compared with the SCD group at week 2 (P<0.05). In addition, the levels of plasma glucose (P<0.05), portal insulin (P<0.05) and content of liver lipid (P<0.01) increased in the HFD group compared with the SCD group. After 6 weeks, the liver steatosis was successfully formed and stable. Consequently, a rat liver developed hepatic macrovesicular steatosis >60%, which was subsequently used for transplantation after double-lobectomy. Post-transplantation survival rates in the HFD and SCD groups were as follows: Week 1, 80 vs. 100% and 1 month, 20 vs. 100%. A total of 20 rats were not sacrificed by performing double-lobectomy for biopsy. Taken together, the results of the present study suggest that rat liver double-lobectomy may be safely applied in steatotic liver transplantation without the need to sacrifice a large number of animals.

Pre-transplant Sarcopenic Obesity Worsens the Survival After Liver Transplantation: A Meta-Analysis and a Systematic Review

Background: The rising prevalence of cirrhotic cases related to non-alcoholic steatohepatitis has led to an increased number of cirrhotic patients with coexistence of obesity and muscle mass loss, known as sarcopenic obesity (SO). In patients undergoing liver transplantation (LT), the presence of SO may worsen prognosis, and increase morbidity and mortality.

Objective: We aimed to evaluate the effect of the presence of pre-transplant SO on the outcomes of LT.

Methods: A comprehensive search was performed in seven medical databases for studies comparing morbidity and mortality of patients with and without SO after LT. The primary outcome was overall mortality in the short- (1 year), intermediate- (3 years), and long- (5 years) term. We calculated pooled relative risks (RRs) with 95% confidence intervals (CIs). Heterogeneity was quantified with I²-statistics.

Results: Based on the analysis of 1,515 patients from three articles, SO increased overall mortality compared to non-SO at short-, intermediate-, and long-term follow-up (RR = 2.06, 95% CI: 1.28-3.33; RR = 1.67, 95% CI: 1.10-2.51; and RR = 2.08, 95% CI: 1.10-3.93, respectively) without significant between-study heterogeneity for the short- and intermediate- term (I² = 0.0% for both) and considerable heterogeneity for long-term follow-up (I² = 81.1%).

Conclusion: Pre-transplant SO proved to be a risk factor after LT and was associated with two times higher mortality at short- and long- term follow-up. Since SO worsens the prognosis of patients after LT, the inclusion of body composition assessment before LT may help to plan a more individualized nutritional treatment, physiotherapy, and postoperative care and may improve morbidity and mortality.

Association between obesity after liver transplantation and steatosis, inflammation, and fibrosis of the graft

BACKGROUND

Nonalcoholic steatohepatitis has become one of the leading causes of liver transplantation. The development of steatosis, as well as the link to inflammation and fibrosis, after transplantation remain poorly understood. The aim of this analysis was to evaluate the influence of obesity on histopathological changes of the graft during long-term follow-up.

METHODS

A total of 1494 longitudinal liver biopsies of 271 recipients were evaluated during a follow-up period of 5 to 10 years. Clinical and laboratory parameters as well as histopathological categories of steatosis, inflammation, and fibrosis were explored by routine protocol biopsies.

RESULTS

The BMI and prevalence of diabetes mellitus significantly increased after transplantation (P < .01). Diabetes and de novo obesity were significantly associated with the degree of graft steatosis. There was no correlation between former steatosis and inflammation or fibrosis. Inflammation was a precursor of fibrosis, and fibrosis increased over the first 3 years (P < .01). No severe graft dysfunction was observed.

CONCLUSION

Obesity and diabetes mellitus correlated with higher grades of steatosis and de novo steatosis after transplantation. Metabolic syndrome must be considered as a serious post-transplant complication that can cause histopathological alteration. However, the progress from steatosis to steatohepatitis is not as common as expected.

Reduction of Polyunsaturated Fatty Acids with Tumor Progression in a Lean Non-Alcoholic Steatohepatitis-Associated Hepatocellular Carcinoma Mouse Model

Background and Aim: Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in Western countries. While obesity and diabetes are the hallmarks of NAFLD, it also develops in lean individuals in the absence of metabolic syndrome, with a prevalence of 7 percent in the U.S. and 25-30 percent in some Asian countries. NAFLD represents the spectrum of liver disease, starting with excess liver fat accumulation (NAFL) that can progress to nonalcoholic steatohepatitis (NASH), cirrhosis and ultimately hepatocellular carcinoma (HCC). To date, the pathogenesis of lean NASH-HCC is poorly understood and a mouse model is lacking. We aimed to develop a mouse model of lean NASH-HCC using a choline deficient and high trans-fat/sucrose/cholesterol diet to enable better understanding of its molecular pathogenesis. Methods: C57BL/6N mice were fed this diet starting at 4 weeks of age for 52 weeks and were compared to mice fed an isocaloric low fat control diet for the same duration. C57BL/6N mice were chosen instead of the C57BL/6J mice due to the high susceptibility of C57BL/6J mice to diet-induced obesity. The plasma and tumor fatty acid profile of these mice was also investigated. Results: Nearly 61% of the mice developed lean NASH-HCC. These mice showed reduction of plasma polyunsaturated fatty acids (PUFAs) (linolenic acids (α and γ, ω-3 and ω-6, respectively), eicosapentanoic acid (ω-3), docosahexanoic acid (ω-3), and linoleic acid (ω-6)) and increasing levels over time in mice with pre-malignant lesions. Conclusions: We developed a novel high penetrance diet-induced lean NASH-HCC mouse model. Plasma PUFA levels were reduced with tumor progression in parallel with reduced expression of genes controlling desaturase expression suggesting their potential use as biomarkers for lean NASH-HCC progression as well as chemopreventive molecules.

S-allylmercaptocysteine improves nonalcoholic steatohepatitis by enhancing AHR/NRF2-mediated drug metabolising enzymes and reducing NF-κB/IκBα and NLRP3/6-mediated inflammation

PURPOSE

To investigate the novel molecular mechanisms of the antioxidant and anti-inflammatory properties of S-allylmercaptocysteine (SAMC) based on a transcriptomic study in a nonalcoholic steatohepatitis (NASH) rat model METHODS: NASH was induced in Sprague-Dawley rats by feeding with a high fat diet (HFD) for 12 weeks. 200 mg/kg SAMC was fed by oral gavage for 4 weeks from 9 to 12 week.

RESULTS

SAMC co-administration attenuated HFD-induced liver injury, including the increased serum ALT, hepatic oxidative stress and inflammation. Transcriptomic analysis revealed that SAMC dramatically induced the XRE- and ARE-driven drug metabolising enzymes (DMEs) including Akr7a3, Akr1b8, and Nqo1. The nuclear translocation of the upstream regulator of xenobiotics metabolism, AHR, and regulator of antioxidant responses, NRF2, were significantly increased by SAMC treatment. Furthermore, SAMC counteracted the effects of HFD on NF-κB/IκB and NLRP3/6 pathways with decreasing protein levels of ASC, cleaved caspase-1, IL-18, and IL-1β. These results were further verified in another mice NASH model induced by an MCD diet with SAMC co-administration.

CONCLUSION

We propose that SAMC triggers AHR/NRF2-mediated antioxidant responses which may further suppress the NLRP3/6 inflammasome pathway and NF-κB activation, contributing to the improvement of NASH.

Low-Dose Sorafenib Acts as a Mitochondrial Uncoupler and Ameliorates Nonalcoholic Steatohepatitis

Nonalcoholic steatohepatitis (NASH) is becoming one of the leading causes of hepatocellular carcinoma (HCC). Sorafenib is the only first-line therapy for advanced HCC despite its serious adverse effects. Here, we report that at an equivalent of approximately one-tenth the clinical dose for HCC, sorafenib treatment effectively prevents the progression of NASH in both mice and monkeys without any observed significant adverse events. Mechanistically, sorafenib's benefit in NASH is independent of its canonical kinase targets in HCC, but involves the induction of mild mitochondrial uncoupling and subsequent activation of AMP-activated protein kinase (AMPK). Collectively, our findings demonstrate a previously unappreciated therapeutic effect and signaling mechanism of low-dose sorafenib treatment in NASH. We envision that this new therapeutic strategy for NASH has the potential to translate into a beneficial anti-NASH therapy with fewer adverse events than is observed in the drug's current use in HCC.

Nonalcoholic fatty liver disease experiences accumulation of hepatic liquid crystal associated with increasing lipophagy

Background

In the past 30 years, incidences of non-alcoholic fatty liver disease (NAFLD) has risen by 30%. However, there is still no clear mechanism or accurate method of anticipating liver failure. Here we reveal the phase transitions of liquid crystalline qualities in hepatic lipid droplets (HLDs) as a novel method of anticipating prognosis.

Methods

NAFLD was induced by feeding C57BL/6J mice on a high-fat (HiF) diet. These NAFLD livers were then evaluated under polarized microscopy, X-ray diffraction and small-angle scattering, lipid component chromatography analysis and protein expression analysis. Optically active HLDs from mouse model and patient samples were both then confirmed to have liquid crystal characteristics. Liver MAP1LC3A expression was then evaluated to determine the role of autophagy in liquid crystal HLD (LC-HLD) formation.

Results

Unlike the normal diet cohort, HiF diet mice developed NAFLD livers containing HLDs exhibiting Maltese cross birefringence, phase transition, and fluidity signature to liquid crystals. These LC-HLDs transitioned to anisotropic crystal at 0 °C and remain crystalline. Temperature increase to 42 °C causes both liquid crystal and crystal HLDs to convert to isotropic droplet form. These isotropic HLDs successfully transition to anisotropic LC with fast temperature decrease and anisotropic crystal with slow temperature decrease. These findings were duplicated in patient liver. Patient LC-HLDs with no inner optical activity were discovered, hinting at lipid saturation as the mechanism through which HLD acquire LC characteristics. Downregulation of MAP1LC3A in conjunction with increased LC-HLD also implicated autophagy in NAFLD LC-HLD formation.

Conclusions

Increasing concentrations of amphiphilic lipids in HLDs favors organization into alternating hydrophilic and hydrophobic layers, which present as LC-HLDs. Thus, evaluating the extent of liquid crystallization with phase transition in HLDs of NAFLD patients may reveal disease severity and predict impending liver damage.

New therapeutic strategies in nonalcoholic fatty liver disease: a focus on promising drugs for nonalcoholic steatohepatitis

The prevalence of nonalcoholic fatty liver disease (NAFLD) is increasing worldwide. Globally, it is currently the most common liver disease and is estimated to affect up to 25% of the population. In the first stage, NAFLD is characterized by simple hepatic steatosis (NAFL, nonalcoholic fatty liver) that might progress to nonalcoholic steatohepatitis (NASH), fibrosis, cirrhosis or hepatocellular carcinoma. In this review, we discuss the global burden of NAFLD, together with future perspectives on how this epidemic could be restrained. There is also an urgent need for the development of new medical strategies for NAFLD patients. We aim to present the beneficial effects of life-style modifications that should be advised to both non-obese and obese NAFLD patients. Since there are currently no medications directly used for the treatment of more advanced NAFLD stages, the central part of this review summarizes ongoing and recently completed clinical trials testing promising drugs for NASH resolution. The marketing of new therapeutic agents would greatly increase the odds of reducing the global burden of NAFLD.

Nonalcoholic Fatty Liver Disease Among Individuals with HIV Mono-infection: A Growing Concern?

PURPOSE OF REVIEW

Liver disease is a leading cause of non-AIDS-related death in the HIV population since the introduction of highly active antiretroviral treatment (HAART). Recent studies suggest that patients with HIV are at high risk for nonalcoholic fatty liver disease (NAFLD) and progressive liver fibrosis. Evidence for the prevalence, risk factors, and diagnostic methodologies of NAFLD in patients with HIV mono-infection is summarized here.

RECENT FINDINGS

Although limited, published studies suggest that the prevalence of NAFLD is higher (30-50%) and progresses at an increased rate in patients with HIV compared to the general population. Identifying those at risk for significant liver fibrosis is critical, preferably with non-invasive screening tests. While there is a paucity of evidence in this population, transient elastography (TE) appears to provide a sensitive, non-invasive screening modality. Identifying NAFLD early will allow for dietary and lifestyle interventions, as well as future drug therapies to decrease the risk of progressive liver fibrosis and cirrhosis in the high-risk HIV population. Clinicians should be aware of this risk and consider using TE for NAFLD diagnosis and surveillance.

Mitochondrial Dysfunction in the Transition from NASH to HCC

The liver constantly adapts to meet energy requirements of the whole body. Despite its remarkable adaptative capacity, prolonged exposure of liver cells to harmful environmental cues (such as diets rich in fat, sugar, and cholesterol) results in the development of chronic liver diseases (including non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH)) that can progress to hepatocellular carcinoma (HCC). The pathogenesis of these diseases is extremely complex, multifactorial, and poorly understood. Emerging evidence suggests that mitochondrial dysfunction or maladaptation contributes to detrimental effects on hepatocyte bioenergetics, reactive oxygen species (ROS) homeostasis, endoplasmic reticulum (ER) stress, inflammation, and cell death leading to NASH and HCC. The present review highlights the potential contribution of altered mitochondria function to NASH-related HCC and discusses how agents targeting this organelle could provide interesting treatment strategies for these diseases.

Hepatoprotective Role of Eclipta alba against High Fatty Diet Treated Experimental Models - A Histopathological Study

Background

The hepatic injury due to oxidative stress was ameliorated through administration of an aqueous extract of Eclipta alba leaves and suggested that wedelolactone and demethylwedelolactone were the possible components of Eclipta alba behind the protective effect on liver as well as against liver disorders.

Objective

To study the hepato-protective effects of Eclipta alba on high fatty diet treated experimental models.

Material and methods

A total of 30 adult albino rats of Wistar strain weighing 165-215 grams, from the animal house of the Basaveshwara Medical College, Hospital and Research Centre, Chitradurga, were used for the present study: group 1 included animals fed with normal diet (control); group 2, animals treated with hyperlipidemic diet for eight weeks; group 3, animals treated with hyperlipidemic diet for eight weeks, followed by one week post treatment of Eclipta alba with normal diet; group 4, animals treated with hyperlipidemic diet for eight weeks, followed by two weeks post-treatment of Eclipta alba with normal diet; and group 5, animals treated with hyperlipidemic diet for eight weeks, followed by three weeks posttreatment of Eclipta alba with normal diet.

Results

In animals with high fat diet (30%), we observed the deposition of fat in the form of fat lobules in and around the hepatocytes, mononuclear in filtration in the liver parenchyma, dilation of blood vessels, necrotic foci and damaged hepatocytes.

Conclusion

The components of Eclipta alba like wedelolactone, demethylwedelolactone and saponins reduced fat deposition, mononuclear infiltration, and necrotic foci, and stimulated hepatocyte regeneration in the liver.

Role of HSD17B13 in the liver physiology and pathophysiology

17β-Hydroxysteroid dehydrogenases (HSD17Bs) comprise a large family of 15 members that are mainly involved in sex hormone metabolism. Some HSD17Bs enzymes also play key roles in cholesterol and fatty acid metabolism. Recent study showed that hydroxysteroid 17β-dehydrogenase 13 (HSD17B13), an enzyme with unknown biological function, is a novel liver-specific lipid droplet (LD)-associated protein in mouse and humans. HSD17B13 expression is markedly upregulated in patients and mice with non-alcoholic fatty liver disease (NAFLD). Hepatic overexpression of HSD17B13 promotes lipid accumulation in the liver. In this review, we summarize recent progress regarding the role of HSD17B13 in the regulation of hepatic lipid homeostasis and discuss genetic, genomic and proteomic evidence supporting the pathogenic role of HSD17B13 in NAFLD. We also emphasize its potential as a biomarker of advanced liver disease, such as non-alcoholic steatohepatitis (NASH) and liver cancer.

MicroRNA-26a-CD36 signaling pathway: Pivotal role in lipid accumulation in hepatocytes induced by PM2.5 liposoluble extracts

Exposure to ambient particular matters (PM) has been associated with the development of non-alcoholic fatty liver disease (NAFLD), but the underlying mechanism remains unclear. Given that microRNA (miRNA) is recognized as a key regulator of lipid metabolism and a potential mediator of environmental cues, this study aimed to explore the role of miRNA-mRNA regulation underlying abnormal lipid metabolism triggered by PM_2.5liposoluble extracts. We confirmed that 72-h exposure to liposoluble extracts of PM_2.5 from Nanjing at 25 μg/cm² induced lipid accumulation in HepG2 cells by promoting uptake of free fatty acids (FFAs). Notably, lipid accumulation induced by PM_2.5 liposoluble extracts was associated with decreased expression of miR-26a and consequent upregulation of fatty acid translocase (FAT, also known as CD36). Using gain- and loss-of-function assays, we demonstrated that miR-26a negatively regulated CD36 to mediate lipid accumulation in HepG2 cells. We further confirmed that miR-26a directly acted on the 3' untranslated region (3'UTR) of CD36. Furthermore, overexpression of miR-26a abolished steatosis in HepG2 cells treated with PM_2.5 liposoluble extracts by suppressing CD36. In addition, we demonstrated that PM_2.5 liposoluble extracts caused inflammation in HepG2 cells by raising p65 phosphorylation, thereby fuelling the transition from simple non-alcoholic fatty liver to non-alcoholic steatohepatitis. In conclusion, this study demonstrated a novel mechanism by which miR-26a-CD36 pathway mediated lipid accumulation induced by PM_2.5 liposoluble extracts in hepatocytes. Lipid accumulation and inflammation induced by PM_2.5 liposoluble extracts implied the potential role of PM_2.5 in developing NAFLD.

Comprehensive bioinformatics analysis of critical lncRNAs, mRNAs and miRNAs in non‑alcoholic fatty liver disease

Non‑alcoholic fatty liver disease (NAFLD) is the most common fatty liver disease in developed countries, in which fat accumulation in the liver is induced by non‑alcoholic factors. The present study was conducted to identify NAFLD‑associated long non‑coding RNAs (lncRNAs), mRNAs and microRNAs (miRNAs). The microarray dataset GSE72756, which included 5 NAFLD liver tissues and 5 controls, was acquired from the Gene Expression Omnibus database. Differentially expressed lncRNAs (DE‑lncRNAs) and mRNAs (DE‑mRNAs) were detected using the pheatmap package. Using the clusterProfiler package and Cytoscape software, enrichment and protein‑protein interaction (PPI) network analyses were conducted to evaluate the DE‑mRNAs. Next, the miRNA‑lncRNA‑mRNA interaction network was visualized using Cytoscape software. Additionally, RP11‑279F6.1 and AC004540.4 expression levels were analyzed by reverse transcription quantitative polymerase chain reaction. There were 318 DE‑lncRNAs and 609 DE‑mRNAs identified in the NAFLD tissues compared with the normal tissues. Jun proto‑oncogene, AP‑1 transcription factor subunit (JUN), which is regulated by AC004540.4 and RP11‑279F6.1, exhibited higher degree compared with other nodes in the PPI network. Furthermore, miR‑409‑3p and miR‑139 (targeting JUN) were predicted as PPI network nodes. In the miRNA‑lncRNA‑mRNA network, miR‑20a and B‑cell lymphoma 2‑like 11 (BCL2L11) were among the top 10 nodes. Additionally, BCL2L11, AC004540.4 and RP11‑279F6.1 were targeted by miR‑20a, miR‑409‑3p and miR‑139 in the miRNA‑lncRNA‑mRNA network, respectively. RP11‑279F6.1 and AC004540.4 expression was markedly enhanced in NAFLD liver tissues. These key RNAs may be involved in the pathogenic mechanisms of NAFLD.

Development and validation of a quantitative ultra performance LC® hydrophilic interaction liquid chromatography MS/MS method to measure fructose and sorbitol in human plasma

AIM

Fructose and sorbitol are utilized as biomarkers for nonalcoholic steatohepatitis. Measurement of fructose and sorbitol levels helps understanding disease progression, drug response and underlying mechanism.

MATERIALS & METHODS

Stable isotope-labeled fructose and sorbitol were used as surrogate standards and internal standards. Human plasma samples were processed and analyzed by ultra performance LC^®-MS/MS via chromatographic separation on a hydrophilic interaction liquid chromatography analytical column without derivatization. Assay was validated with biomarker fit-for-purpose concept.

RESULTS

A 12-min ultra performance LC^®-MS/MS method was developed and validated to directly measure fructose and sorbitol in human plasma with acceptable intra- and inter-assay precision and accuracy.

CONCLUSION

This sensitive, selective, and high-throughput assay with suitable dynamic ranges was successfully applied to clinical studies to provide reliable fructose and sorbitol biomarker data.

Green cardamom supplementation improves serum irisin, glucose indices, and lipid profiles in overweight or obese non-alcoholic fatty liver disease patients: a double-blind randomized placebo-controlled clinical trial

Background

Despite the reported health effects of cardamom on dyslipidemia, hepatomegaly, and fasting hyperglycemia, no human research has studied its potency in non-alcoholic fatty liver disease (NAFLD) as the hepatic part of metabolic syndrome. Our aim was determining the effects of green cardamom (GC) on serum glucose indices, lipids, and irisin level among overweight or obese NAFLD patients.

Methods

The place of participant recruitment was the polyclinic of the National Iranian Oil Company (NIOC) central hospital in Tehran. Based on the ultrasonography and eligibility criteria, 87 participants were randomly divided into two groups as cardamom (n = 43) or placebo (n = 44). The supplementation was two 500 mg capsules 3 times/day with meals for 3 months. Serum irisin, fasting blood sugar (FBS), insulin (FBI), total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-c), and high-density lipoprotein cholesterol (HDL-c) were measured. Quantitative insulin sensitivity check index (QUICKI) and homeostasis model assessment-insulin resistance (HOMA-IR) were also calculated.

Results

In comparison with placebo, GC significantly increased irisin, HDL-c, and QUICKI and decreased FBI, TG, LDL-c, HOMA-IR, and the grade of fatty liver (P < 0.05). After adjustment for confounders, the changes were similar (P < 0.05) with an exception for LDL-c which had a trend (P = 0.07). The differences in FBS, TC, and body mass index (BMI) were not significant (P > 0.05).

Conclusion

GC supplement improved the grade of fatty liver, serum glucose indices, lipids, and irisin level among overweight or obese NAFLD patients. The changes in these biomarkers may yield beneficial effects on NAFLD. Further trials on the efficacy of GC for clinical practice are suggested.

Trial registration

Iranian Registry of Clinical Trials, IRCT2015121317254N4. Registered 27/12/2015,

Electronic supplementary material

The online version of this article (10.1186/s12906-019-2465-0) contains supplementary material, which is available to authorized users.

Increasing Incidence of Nonalcoholic Steatohepatitis as an Indication for Liver Transplantation in Australia and New Zealand

The worldwide increase in obesity and diabetes has led to predictions that nonalcoholic steatohepatitis (NASH) will become the leading indication for orthotopic liver transplantation (OLT). Data supporting this prediction from outside the United States are limited. Thus, we aimed to determine trends in the frequency of NASH among adults listed and undergoing OLT in Australia and New Zealand (ANZ) from 1994 to 2017. Data from the ANZ Liver Transplant Registry were analyzed with patients listed for fulminant liver failure, retransplantation, or multivisceral transplants excluded. Nonparametric trend, Spearman rank correlation, and regression analysis were used to assess trends in etiologies of liver disease over time. Of 5016 patient wait-list registrants, a total of 3470 received an OLT. The percentage of patients with NASH activated for OLT increased significantly from 2.0% in 2003 to 10.9% in 2017 (trend analyses; P < 0.001). In 2017, NASH was the third leading cause of chronic liver disease (CLD) among wait-list registrants behind chronic hepatitis C virus (HCV; 29.5%) and alcohol (16.1%). Similarly, significant increases over time in the percentage of patients undergoing OLT were observed for HCV and NASH (all trend analyses; P < 0.001) but with significant reductions in primary sclerosing cholangitis and cryptogenic cirrhosis (both P < 0.05). By 2017, NASH was the third leading cause of liver disease among patients undergoing OLT (12.4%) and behind chronic HCV (30.2%) and alcohol (18.2%). NASH also became the third most frequent etiology of CLD in patients transplanted (13.8%) with concomitant hepatocellular carcinoma by 2017. In conclusion, NASH is increasing as a primary etiology of liver disease requiring listing and liver transplantation in ANZ.

Obesity Drives STAT-1-Dependent NASH and STAT-3-Dependent HCC

Obesity is a major driver of cancer, especially hepatocellular carcinoma (HCC). The prevailing view is that non-alcoholic steatohepatitis (NASH) and fibrosis or cirrhosis are required for HCC in obesity. Here, we report that NASH and fibrosis and HCC in obesity can be dissociated. We show that the oxidative hepatic environment in obesity inactivates the STAT-1 and STAT-3 phosphatase T cell protein tyrosine phosphatase (TCPTP) and increases STAT-1 and STAT-3 signaling. TCPTP deletion in hepatocytes promoted T cell recruitment and ensuing NASH and fibrosis as well as HCC in obese C57BL/6 mice that normally do not develop NASH and fibrosis or HCC. Attenuating the enhanced STAT-1 signaling prevented T cell recruitment and NASH and fibrosis but did not prevent HCC. By contrast, correcting STAT-3 signaling prevented HCC without affecting NASH and fibrosis. TCPTP-deletion in hepatocytes also markedly accelerated HCC in mice treated with a chemical carcinogen that promotes HCC without NASH and fibrosis. Our studies reveal how obesity-associated hepatic oxidative stress can independently contribute to the pathogenesis of NASH, fibrosis, and HCC.

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Obesity promotes hepatic STAT-1 and STAT-3 signaling

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Obesity promotes STAT-1-dependent T cell-infiltration, NASH, and fibrosis

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Obesity promotes NASH-independent STAT-3-dependent HCC