Vitamin E and nonalcoholic fatty liver disease

Reversal of Fatty Liver With Regression of Acute Necrotizing Pancreatitis: A Rare Case

Acute pancreatitis is a severe inflammatory condition that can lead to systemic repercussions, one of which is the development of hepatic steatosis (fatty liver). The accumulation of fat in liver cells can complicate the course of pancreatitis, exacerbating inflammation and causing additional metabolic disturbances. The presence of fatty liver in the context of acute pancreatitis can thus worsen the overall clinical picture, making management more challenging and potentially leading to further complications. Here, we discuss a rare case of a 34-year-old female who demonstrated the reversal of fatty liver following the improvement of acute pancreatitis. This case highlights the dynamic relationship between acute pancreatitis and hepatic steatosis, illustrating that effective management of pancreatitis can lead to significant improvements in associated conditions such as fatty liver.

Metabolic-Dysfunction-Associated Steatotic Liver Disease (MASLD) after Liver Transplantation: A Narrative Review of an Emerging Issue

The development of steatotic liver disease after liver transplant (LT) is widely described, and epidemiological data have revealed an increased incidence in recent times. Its evolution runs from simple steatosis to steatohepatitis and, in a small proportion of patients, to significant fibrosis and cirrhosis. Apparently, post-LT steatotic disease has no impact on the recipient's overall survival; however, a higher cardiovascular and malignancy burden has been reported. Many donors' and recipients' risk factors have been associated with this occurrence, although the recipient-related ones seem of greater impact. Particularly, pre- and post-LT metabolic alterations are strictly associated with steatotic graft disease, sharing common pathophysiologic mechanisms that converge on insulin resistance. Other relevant risk factors include genetic variants, sex, age, baseline liver diseases, and immunosuppressive drugs. Diagnostic evaluation relies on liver biopsy, although non-invasive methods are being increasingly used to detect and monitor both steatosis and fibrosis stages. Management requires a multifaceted approach focusing on lifestyle modifications, the optimization of immunosuppressive therapy, and the management of metabolic complications. This review aims to synthesize the current knowledge of post-LT steatotic liver disease, focusing on the recent definition of metabolic-dysfunction-associated steatotic liver disease (MASLD) and its metabolic and multisystemic concerns.

Oxidative Stress as a Target for Non-Pharmacological Intervention in MAFLD: Could There Be a Role for EVOO?

Oxidative stress plays a central role in most chronic liver diseases and, in particular, in metabolic dysfunction-associated fatty liver disease (MAFLD), the new definition of an old condition known as non-alcoholic fatty liver disease (NAFLD). The mechanisms leading to hepatocellular fat accumulation in genetically predisposed individuals who adopt a sedentary lifestyle and consume an obesogenic diet progress through mitochondrial and endoplasmic reticulum dysfunction, which amplifies reactive oxygen species (ROS) production, lipid peroxidation, malondialdehyde (MDA) formation, and influence the release of chronic inflammation and liver damage biomarkers, such as pro-inflammatory cytokines. This close pathogenetic link has been a key stimulus in the search for therapeutic approaches targeting oxidative stress to treat steatosis, and a number of clinical trials have been conducted to date on subjects with NAFLD using drugs as well as supplements or nutraceutical products. Vitamin E, Vitamin D, and Silybin are the most studied substances, but several non-pharmacological approaches have also been explored, especially lifestyle and diet modifications. Among the dietary approaches, the Mediterranean Diet (MD) seems to be the most reliable for affecting liver steatosis, probably with the added value of the presence of extra virgin olive oil (EVOO), a healthy food with a high content of monounsaturated fatty acids, especially oleic acid, and variable concentrations of phenols (oleocanthal) and phenolic alcohols, such as hydroxytyrosol (HT) and tyrosol (Tyr). In this review, we focus on non-pharmacological interventions in MAFLD treatment that target oxidative stress and, in particular, on the role of EVOO as one of the main antioxidant components of the MD.

Therapeutic management of metabolic dysfunction associated steatotic liver disease

The incidence and prevalence of non-alcoholic fatty liver disease (NAFLD) have been steadily increasing worldwide, with a huge societal and economic burden. Recently, NAFLD and non-alcoholic steatohepatitis have been renamed and redefined as metabolic dysfunction associated steatotic liver disease (MASLD) and steatohepatitis (Metabolic Dysfunction Associated Steatohepatitis (MASH)), which result from an imbalance between metabolic and inflammatory stress (mainly as a consequence of adipose tissue dysfunction and insulin resistance) and the defence and repair mechanisms of the steatotic liver. Once MASLD progresses to end-stage of liver disease, treatment efficacy becomes limited and may require liver transplantation. Early detection and intervention are crucial. Lifestyle modification is consequently the cornerstone of its management. Timely consideration of bariatric surgeries should be given to patients meeting specific criteria. A multidisciplinary approach is warranted, starting from the concept that MASLD/MASH is at the centre of the cardiovascular-liver-metabolic syndrome. In some cases, pharmacological treatment can complement lifestyle modification. Several drugs used to treat the cardiometabolic co-morbidities have some potential efficacy in slowing Down disease progression, and some have demonstrated efficacy on histological endpoints that are likely to translate into long-term clinical benefits. Optimising the use of these drugs within their licenced indications is thus paramount for patients with MASLD. Several MASH-specific drugs are on the horizon and are likely to enrich our therapeutic armamentarium in the near future, particularly in non-cirrhotic stages of the disease. Much work still needs to be done to understand the specific features of MASH cirrhosis and develop efficacious treatments for this disease stage.

Abnormal metabolism in hepatic stellate cells: Pandora's box of MAFLD related hepatocellular carcinoma

Metabolic associated fatty liver disease (MAFLD) is a significant risk factor for the development of hepatocellular carcinoma (HCC). Hepatic stellate cells (HSCs), as key mediators in liver injury response, are believed to play a crucial role in the repair process of liver injury. However, in MAFLD patients, the normal metabolic and immunoregulatory mechanisms of HSCs become disrupted, leading to disturbances in the local microenvironment. Abnormally activated HSCs are heavily involved in the initiation and progression of HCC. The metabolic disorders and abnormal activation of HSCs not only initiate liver fibrosis but also contribute to carcinogenesis. In this review, we provide an overview of recent research progress on the relationship between the abnormal metabolism of HSCs and the local immune system in the liver, elucidating the mechanisms of immune imbalance caused by abnormally activated HSCs in MAFLD patients. Based on this understanding, we discuss the potential and challenges of metabolic-based and immunology-based mechanisms in the treatment of MAFLD-related HCC, with a specific focus on the role of HSCs in HCC progression and their potential as targets for anti-cancer therapy. This review aims to enhance researchers' understanding of the importance of HSCs in maintaining normal liver function and highlights the significance of HSCs in the progression of MAFLD-related HCC.

Mitochondrial Dysfunction in Metabolic Dysfunction Fatty Liver Disease (MAFLD)

Nonalcoholic fatty liver disease (NAFLD) has become an increasingly common disease in Western countries and has become the major cause of liver cirrhosis or hepatocellular carcinoma (HCC) in addition to viral hepatitis in recent decades. Furthermore, studies have shown that NAFLD is inextricably linked to the development of extrahepatic diseases. However, there is currently no effective treatment to cure NAFLD. In addition, in 2020, NAFLD was renamed metabolic dysfunction fatty liver disease (MAFLD) to show that its pathogenesis is closely related to metabolic disorders. Recent studies have reported that the development of MAFLD is inextricably associated with mitochondrial dysfunction in hepatocytes and hepatic stellate cells (HSCs). Simultaneously, mitochondrial stress caused by structural and functional disorders stimulates the occurrence and accumulation of fat and lipo-toxicity in hepatocytes and HSCs. In addition, the interaction between mitochondrial dysfunction and the liver-gut axis has also become a new point during the development of MAFLD. In this review, we summarize the effects of several potential treatment strategies for MAFLD, including antioxidants, reagents, and intestinal microorganisms and metabolites.

Methotrexate-induced hepatotoxicity in rats and the therapeutic properties of vitamin E: a histopathologic and flowcytometric research

Aim of the study

Methotrexate (MTX) causes oxidative stress-related liver damage. Our objective was to investigate the protective effects of vitamin E against MTX-induced hepatotoxicity through histopathological methods and flow cytometry.

Material and methods

The rats were assigned to four groups: Control (2 ml saline for 5 days), MTX (20 mg/kg intraperitoneally (i.p.) only on the initial day of the study), MTX + vitamin E (20 mg/kg MTX (i.p.) only on the first day, and 100 mg/kg vitamin E (i.p.) was applied for 5 days during the study), Vitamin E (100 mg/kg of vitamin E (i.p.) was given for five days). Histopathologic changes and the flow cytometric apoptotic index were evaluated for liver tissue. The Kruskal-Wallis test was used for comparisons between groups. The statistical significance level was accepted as p < 0.05.

Results

In the histopathological analysis, hepatocyte degeneration, dilatation of sinusoids, mononuclear cell infiltration, hydropic degeneration in hepatocytes, vacuolization, and pycnotic nucleus were observed in the MTX group. In the MTX + vitamin E group, hepatocyte degeneration, pycnotic nuclei, and dilatation in sinusoids were significantly lower compared to the MTX group. In the MTX group, glycogen accumulation in hepatocytes was lower compared to the control group. In the MTX + vitamin E group, glycogen accumulation in hepatocy-tes was higher compared to the MTX group. The flowcytometric apoptotic index (AI) percentage in the MTX group was 34.4% and in the MTX + vitamin E group the value was 9.4%.

Conclusions

Our results demonstrated that vitamin E ameliorates MTX-induced liver damage. Co-using vitamin E and MTX drugs will be beneficial for the treatment of various diseases.

Association between potential supplement-drug interactions and liver diseases in patients with cancer: A large prospective cohort study

BACKGROUND & AIMS

The concurrent use of herbal and dietary supplements and conventional drugs can lead to interactions in patients with cancer, of which hepatotoxicity is one of the most concerning sequelae. This study examined the potential supplement-drug interactions involving the hepatic system, and their associations with documented liver diseases, among patients with cancer in a large population-based cohort in the UK Biobank.

METHODS

Participants diagnosed with cancer and had completed supplement-use assessment after diagnosis were included. Potentially interacting supplement-drug combinations that involved CYP enzymes or increased the risk of hepatotoxicity were identified from four tertiary databases. Liver diseases were identified using ICD-codes K70-77. Log-binomial regression was used to investigate the associations between potentially-interacting supplement-drug combinations and liver diseases documented (1) at any time, and (2) confined to only after the time of supplement-use assessment, adjusting for age, sex and pre-existing comorbidities.

RESULTS

This analysis included 30,239 participants (mean age = 60.0 years; 61.9% female). Over half (n = 17,698, 58.5%) reported the use of supplements after cancer diagnoses. Among supplements users, 36.9% (n = 6537/17,698) were on supplement-drug combinations with interacting potential involving the hepatic system. Patients taking supplements and drugs who had hepatic comorbidities were more likely to take potentially interacting pairs (adjusted risk ratio = 1.14, 95% CI = 1.06-1.23, p < 0.001). However, no significant association was observed between the use of these combinations and subsequent liver diseases (all p > 0.05).

CONCLUSION

Approximately one-third of the participants who had cancer and were supplement users had a risk of potential supplement-drug interactions that contribute to adverse liver effect. Healthcare professionals should communicate with patients with cancer, especially those with pre-existing liver diseases, about supplement use and proactively assess the clinical significance of potential interactions.

From Non-Alcoholic Steatohepatitis (NASH) to Hepatocellular Carcinoma (HCC): Epidemiology, Incidence, Predictions, Risk Factors, and Prevention

Non-alcoholic fatty liver disease (NAFLD) affects up to a quarter of the adult population in many developed and developing countries. This spectrum of liver disease ranges from simple steatosis to non-alcoholic steatohepatitis (NASH) and cirrhosis. The incidence of NASH is projected to increase by up to 56% over the next 10 years. There is growing epidemiological evidence that NAFLD has become the fastest-growing cause of hepatocellular carcinoma (HCC) in industrialized countries. The annual incidence of HCC varies between patients with NASH cirrhosis and patients with noncirrhotic NAFLD. In this review, NAFLD/NASH-associated HCC will be described, including its epidemiology, risk factors promoting hepatocarcinogenesis, and management of HCC in patients with obesity and associated metabolic comorbidities, including preventive strategies and therapeutic approaches to address this growing problem.

α-Tocopherol reduces VLDL secretion through modulation of intracellular ER-to-Golgi transport of VLDL

Avoiding hepatic steatosis is crucial for preventing liver dysfunction, and one mechanism by which this is accomplished is through synchronization of the rate of very low density lipoprotein (VLDL) synthesis with its secretion. Endoplasmic reticulum (ER)-to-Golgi transport of nascent VLDL is the rate-limiting step in its secretion and is mediated by the VLDL transport vesicle (VTV). Recent in vivo studies have indicated that α-tocopherol (α-T) supplementation can reverse steatosis in nonalcoholic fatty liver disease, but its effects on hepatic lipoprotein metabolism are poorly understood. Here, we investigated the impact of α-T on hepatic VLDL synthesis, secretion, and intracellular ER-to-Golgi VLDL trafficking using an in vitro model. Pulse-chase assays using [3H]-oleic acid and 100 µmol/L α-T demonstrated a disruption of early VLDL synthesis, resulting in enhanced apolipoprotein B-100 expression, decreased expression in markers for VTV budding, ER-to-Golgi VLDL transport, and reduced VLDL secretion. Additionally, an in vitro VTV budding assay indicated a significant decrease in VTV production and VTV-Golgi fusion. Confocal imaging of lipid droplet (LD) localization revealed a decrease in overall LD retention, diminished presence of ER-associated LDs, and an increase in Golgi-level LD retention. We conclude that α-T disrupts ER-to-Golgi VLDL transport by modulating the expression of specific proteins and thus reduces VLDL secretion.

Inhibition of glutathione generation in hepatic steatotic rats augments oxidative stress

Fatty liver disease has been strongly associated with a low glutathione (GSH) level in hepatocytes with increased oxidative stress, which is critically involved in the initiation and progression of the disease. The study investigated whether the GSH deficiency induced by buthionine sulfoximine (BSO), an inhibitor of γ-glutamyl cysteine synthetase, can be restored by the administration of GSH ester. We showed that mice fed a diet with cholesterol plus sodium cholate developed steatosis followed by hepatic GSH reduction. Moreover, the GSH level in the cytosol and mitochondria of steatosis plus BSO decreased than that of steatosis alone. Subsequent studies with the liver tissues and plasma of BSO plus steatosis revealed the accumulation of cholesterol in the hepatocytes, downregulating the concentration of GSH, antioxidant enzymes, and GSH metabolizing enzymes with a significant rise in reactive oxygen species (ROS), blood glucose level and plasma lipid profile. The administration of GSH ester in BSO-administered mice, prevented the depletion of GSH by upregulating the GSH concentration, antioxidant enzymes, and GSH metabolizing enzymes, followed by a reduction in ROS and plasma lipid concentration. The histopathological analysis showed a marked increase in inflammation followed by hepatocytes ballooning in BSO-induced group and steatosis control group, which was ameliorated by GSH ester administration. In conclusion, our data suggest that the restoration of GSH in the cytosol and mitochondria through the injection with GSH ester plays a principal role in maintaining the GSH level in the liver, thereby delaying the progression of fatty liver disease.

NAFLD and nutraceuticals: a review of completed phase III and IV clinical trials

Background

Nonalcoholic Fatty Liver Disease (NAFLD) has become a significant public health concern, affecting approximately one-fourth of the population. Despite its prevalence, no FDA-approved drug treatments specifically target NAFLD.

Aim

To provide a review of clinical trials investigating the use of herbal remedies and dietary supplements in NAFLD management, utilizing the ClinicalTrials.gov database.

Methods

This review evaluates the current evidence by examining completed phase III and IV clinical trials registered on ClinicalTrials.gov. An exhaustive search was performed on April 17, 2023, using the terms "Nonalcoholic Fatty Liver Disease" and "NAFLD." Two independent reviewers appraised eligible trials based on pre-defined inclusion and exclusion criteria.

Results

An initial search yielded 1,226 clinical trials, with 12 meeting the inclusion criteria after filtration. The majority of trials focused on Omega-3 fatty acids (20.0%) and vitamin D (26.7%), followed by caffeine, chlorogenic acid, ginger, phosphatidylcholine, Trigonella Foenum-graecum seed extract, vitamin C, and vitamin E (each 6.7%). Most studies were Phase 3 (75.0%) and used a parallel assignment model (91.7%). Quadruple masking was the most prevalent technique (58.3%), and Iran was the leading country in terms of trial locations (25.0%). These interventions constitute two herbal interventions and nine supplement interventions.

Conclusion

This reveals a diverse range of nutraceuticals, with Omega-3 fatty acids and vitamin D being predominant in the management of NAFLD. The global distribution of trials highlights the widespread interest in these therapeutics. However, more rigorous, large-scale trials are needed to establish safety, efficacy, and optimal dosages.

Associations of altered hepatic gene expression in American lifestyle-induced obesity syndrome diet-fed mice with metabolic changes during NAFLD development and progression

Non-alcoholic fatty liver disease (NAFLD) pathogenesis remains poorly understood due to the complex metabolic and inflammatory changes in the liver. This study aimed to elucidate hepatic events related to inflammation and lipid metabolism and their linkage with metabolic alterations during NAFLD in American lifestyle-induced obesity syndrome (ALIOS) diet-fed mice. Forty-eight C57BL/6J male mice were fed with ALIOS diet (n=24) or control chow diet (n=24) for 8, 12, and 16 weeks. At the end of each timepoint, eight mice were sacrificed where plasma and liver were collected. Hepatic fat accumulation was followed using magnetic resonance imaging and confirmed with histology. Further, targeted gene expression and non-targeted metabolomics analysis were conducted. Our results showed higher hepatic steatosis, body weight, energy consumption, and liver mass in ALIOS diet-fed mice compared to control mice. ALIOS diet altered expression of genes related to inflammation (Tnfa and IL-6) and lipid metabolism (Cd36, Fasn, Scd1, Cpt1a, and Ppara). Metabolomics analysis indicated decrease of lipids containing polyunsaturated fatty acids such as LPE(20:5) and LPC(20:5) with increase of other lipid species such as LPI(16:0) and LPC(16:2) and peptides such as alanyl-phenylalanine and glutamyl-arginine. We further observed novel correlations between different metabolites including sphingolipid, lysophospholipids, peptides, and bile acid with inflammation, lipid uptake and synthesis. Together with the reduction of antioxidant metabolites and gut microbiota-derived metabolites contribute to NAFLD development and progression. The combination of non-targeted metabolomics with gene expression in future studies can further identify key metabolic routes during NAFLD which could be the targets of potential novel therapeutics.

Nutritional Genomics in Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a common chronic condition associated with genetic and environmental factors in which fat abnormally accumulates in the liver. NAFLD is epidemiologically associated with obesity, type 2 diabetes, and dyslipidemia. Environmental factors, such as physical inactivity and an unbalanced diet, interact with genetic factors, such as epigenetic mechanisms and polymorphisms for the genesis and development of the condition. Different genetic polymorphisms seem to be involved in this context, including variants in PNPLA3, TM6SF2, PEMT, and CHDH genes, playing a role in the disease's susceptibility, development, and severity. From carbohydrate intake and weight loss to omega-3 supplementation and caloric restriction, different dietary and nutritional factors appear to be involved in controlling the onset and progression of NAFLD conditions influencing metabolism, gene, and protein expression. The polygenic risk score represents a sum of trait-associated alleles carried by an individual and seems to be associated with NAFLD outcomes depending on the dietary context. Understanding the exact extent to which lifestyle interventions and genetic predispositions can play a role in the prevention and management of NAFLD can be crucial for the establishment of a personalized and integrative approach to patients.

Comparative effects of thymol and vitamin E on nonalcoholic fatty liver disease in male Wistar rats

Following the obesity epidemics, nonalcoholic fatty liver disease (NAFLD) has grown in prevalence and become a main cause of morbidity and death, intimately linked to cardiovascular disease, cancer, and cirrhosis. The key factor in the evolution of NAFLD is thought to be oxidative stress. Because most patients cannot change their lifestyle or dietary habits, a pharmaceutical strategy is now required to treat NAFLD. Nonalcoholic fatty liver disease (NAFLD), including nonalcoholic steatohepatitis, is treated with vitamin E. (NASH). Vitamin E is also a powerful antioxidant that has been demonstrated to lower oxidative stress in people with NAFLD. Thymol is a monoterpene phenol with a variety of pharmacological effects, however its anti-fatty liver properties have yet to be investigated. Despite the fact that oxidative stress is thought to have a role in the etiology of nonalcoholic steatohepatitis, antioxidant therapies have not been well studied in the treatment of nonalcoholic steatohepatitis. The goal was to learn more about vitamin E and thymol's biological activities, with a particular emphasis on their therapeutic effectiveness in NAFLD. Four groups of thirty-two adult male rats were formed (healthy control, thymol, Vit E, and fatty liver). For 28 days, rats were given either oral vitamin E (200 mg/kg) or thymol (50 mg/kg) randomly. The levels of ALT, AST, TNF- α, Ferritin, CK-MB enzymes, and MAPK gene expression were then determined in the serum. Based on a random effect model analysis, at the end of 28 days of therapy, ALT (41.43 U/L), AST (47.91 U/L), Ferritin (1.13 pg/dl), CK-MB (251.22 IU/L), TNF-α (95.39 pg/mL) (p≤0.001), and MAPK gene expression levels (p≤0.05) significantly reduced in both experimental groups compared with the fatty liver group. Vitamin E and thymol therapy is a safe, affordable, and effective therapeutic option in the fatty liver group. Patients with fatty liver disease should be encouraged to take vitamin E and Thymol supplements, which are both safe and affordable, because more effective new therapeutic options are lacking.

Sea buckthorn pulp and seed oils ameliorate lipid metabolism disorders and modulate gut microbiota in C57BL/6J mice on high-fat diet

Introduction

Non-alcoholic fatty liver diseases (NAFLD), along with the complications of obesity and dyslipidemia, are worldwide lipid metabolism disorders. Recent evidence showed that NAFLD could be ameliorated by diet and lifestyles by attenuating gut microbiota dysbiosis via the gut-liver axis. Sea buckthorn oils, including sea buckthorn pulp oil (SBPO) and sea buckthorn seed oil (SBSO), were investigated in this study for their beneficial effects on gut-liver axis in C57BL/6J mice on a high-fat diet.

Methods

Sixty of male C57BL/6J mice were assigned into five groups, fed with low-fat diet containing soybean oil (SO), high-fat diet comprising lard oil (LO), peanut oil (PO), SBSO or SBPO, respectively, for 12 weeks. Serum and hepatic biochemical analysis, liver and perirenal fat histological analysis, and fecal 16S rRNA gene sequencing were conducted to reflect the influence of five diets on gut-liver axis.

Results

Dietary SBPO reduced visceral fat accumulation, adipose cell size, serum and hepatic triglyceride, LDL-C levels, and hepatic cell damage score; increased gut microbiota diversity with a higher abundance of Lactobacillus, Roseburia, and Oscillibacter compared with PO. SBSO showed equal or weaker effects compared to SBPO.

Conclusion

This study demonstrates that dietary SBPO has the potential to ameliorate NAFLD and related metabolic disorders, like obesity and dyslipidemia, by modulating gut microbiota.

Molecular mechanisms of metabolic associated fatty liver disease (MAFLD): functional analysis of lipid metabolism pathways

The metabolic-associated fatty liver disease (MAFLD) is a condition of fat accumulation in the liver in combination with metabolic dysfunction in the form of overweight or obesity and insulin resistance. It is also associated with an increased cardiovascular disease risk, including hypertension and atherosclerosis. Hepatic lipid metabolism is regulated by a combination of the uptake and export of fatty acids, de novo lipogenesis, and fat utilization by β-oxidation. When the balance between these pathways is altered, hepatic lipid accumulation commences, and long-term activation of inflammatory and fibrotic pathways can progress to worsen the liver disease. This review discusses the details of the molecular mechanisms regulating hepatic lipids and the emerging therapies targeting these pathways as potential future treatments for MAFLD.

Hepatic Myofibroblasts: A Heterogeneous and Redox-Modulated Cell Population in Liver Fibrogenesis

During chronic liver disease (CLD) progression, hepatic myofibroblasts (MFs) represent a unique cellular phenotype that plays a critical role in driving liver fibrogenesis and then fibrosis. Although they could originate from different cell types, MFs exhibit a rather common pattern of pro-fibrogenic phenotypic responses, which are mostly elicited or sustained both by oxidative stress and reactive oxygen species (ROS) and several mediators (including growth factors, cytokines, chemokines, and others) that often operate through the up-regulation of the intracellular generation of ROS. In the present review, we will offer an overview of the role of MFs in the fibrogenic progression of CLD from different etiologies by focusing our attention on the direct or indirect role of ROS and, more generally, oxidative stress in regulating MF-related phenotypic responses. Moreover, this review has the purpose of illustrating the real complexity of the ROS modulation during CLD progression. The reader will have to keep in mind that a number of issues are able to affect the behavior of the cells involved: a) the different concentrations of reactive species, b) the intrinsic state of the target cells, as well as c) the presence of different growth factors, cytokines, and other mediators in the extracellular microenvironment or of other cellular sources of ROS.

Administration of Glutaredoxin-1 Attenuates Liver Fibrosis Caused by Aging and Non-Alcoholic Steatohepatitis

Liver fibrosis is a sign of non-alcoholic fatty liver disease progression towards steatohepatitis (NASH) and cirrhosis and is accelerated by aging. Glutaredoxin-1 (Glrx) controls redox signaling by reversing protein S-glutathionylation, induced by oxidative stress, and its deletion causes fatty liver in mice. Although Glrx regulates various pathways, including metabolism and apoptosis, the impact of Glrx on liver fibrosis has not been studied. Therefore, we evaluated the role of Glrx in liver fibrosis induced by aging or by a high-fat, high-fructose diet. We found that: (1) upregulation of Glrx expression level inhibits age-induced hepatic apoptosis and liver fibrosis. In vitro studies indicate that Glrx regulates Fas-induced apoptosis in hepatocytes; (2) diet-induced NASH leads to reduced expression of Glrx and higher levels of S-glutathionylated proteins in the liver. In the NASH model, hepatocyte-specific adeno-associated virus-mediated Glrx overexpression (AAV-Hep-Glrx) suppresses fibrosis and apoptosis and improves liver function; (3) AAV-Hep-Glrx significantly inhibits transcription of Zbtb16 and negatively regulates immune pathways in the NASH liver. In conclusion, the upregulation of Glrx is a potential therapeutic for the reversal of NASH progression by attenuating inflammatory and fibrotic processes.

Depletion and enrichment of phytosterols in soybean oil lipid emulsions directly associate with serum markers of cholestasis in preterm parenteral nutrition-fed pigs

BACKGROUND

Clinical reports show a positive correlation between phytosterol concentrations and severity of cholestatic liver disease markers in infants during long-term administration of parenteral lipid emulsions. Establishing a causal link between phytosterols and cholestasis has been complicated by confounding factors of lipid emulsion load, fatty acid composition, and vitamin E in many of these studies. The goal of this study is to determine whether altering the phytosterol concentration within a common soybean oil-based emulsion will alter the onset and severity of cholestasis in parenterally fed preterm piglets.

METHODS

Preterm piglets were administered, for 21 days, either enteral nutrition (ENT) or parenteral nutrition (PN) prepared from a soybean oil-based emulsion containing either 24.0% (depleted [DEP]), 100% (Intralipid; normal phytosterol [NP] concentration), or 144% (enriched [ENR]) total phytosterol concentration.

RESULTS

At the end of the study, plasma and liver phytosterol concentrations were highest in the ENR group, followed by NP and then DEP and ENT. Serum direct bilirubin, serum bile acids, and γ-glutamyltransferase were higher in the ENR and NP groups compared with either DEP or ENT groups. All PN lipid groups showed evidence of mild hepatic steatosis but no change in hepatic expression of proinflammatory cytokines or Farnesoid X receptor target genes.

CONCLUSION

The increase in serum direct bilirubin was lower in the DEP group vs the lipid emulsions with normal or ENR phytosterols. Our results provide additional evidence that phytosterols are linked to an increase in serum markers of cholestasis in preterm PN-fed pigs.

Lipid oxidation that is, and is not, inhibited by vitamin E: Consideration about physiological functions of vitamin E

Lipids are oxidized in vivo by multiple oxidizing species with different properties, some by regulated manner to produce physiological mediators, while others by random mechanisms to give detrimental products. Vitamin E plays an important role as a physiologically essential antioxidant to inhibit unregulated lipid peroxidation by scavenging lipid peroxyl radicals to break chain propagation independent of the type of free radicals which induce chain initiation. Kinetic data suggest that vitamin E does not act as an efficient scavenger of nitrogen dioxide radical, carbonate anion radical, and hypochlorite. The analysis of regio- and stereo-isomer distribution of the lipid oxidation products shows that, apart from lipid oxidation by CYP enzymes, the free radical-mediated lipid peroxidation is the major pathway of lipid oxidation taking place in humans. Compared with healthy subjects, the levels of racemic and trans,trans-hydro (pero)xyoctadecadienoates, specific biomarker of free radical lipid oxidation, are elevated in the plasma of patients including atherosclerosis and non-alcoholic fatty liver diseases. α-Tocopherol acts as a major antioxidant, while γ-tocopherol scavenges nitrogen dioxide radical, which induces lipid peroxidation, nitration of aromatic compounds and unsaturated fatty acids, and isomerization of cis-fatty acids to trans-fatty acids. It is essential to appreciate that the antioxidant effects of vitamin E depend on the nature of both oxidants and substrates being oxidized. Vitamin E, together with other antioxidants such as vitamin C, contributes to the inhibition of detrimental oxidation of biological molecules and thereby to the maintenance of human health and prevention of diseases.

Magnesium intake is inversely associated with risk of non-alcoholic fatty liver disease among American adults

PURPOSE

Human data are limited linking magnesium (Mg) intake to the risk of non-alcoholic fatty liver disease (NAFLD). We aimed to examine the association between Mg intake and the risk of NAFLD among young adults in the US with a 25-year follow-up.

METHODS

This study included 2685 participants from the Coronary Artery Risk Development in Young Adult (CARDIA) study. Diet and dietary supplements were assessed at baseline (1985-1986) and exam years 7 and 20 using an interview-based dietary history. NAFLD, defined as liver attenuation ≤ 51 Hounsfield Units excluding secondary causes of liver fat accumulation, was identified by non-contrast-computed tomography scanning at exam year 25. Multivariable-adjusted logistic regression model was used to examine the associations between cumulative average total intake of Mg (dietary plus supplemental) and NAFLD odds.

RESULTS

A total of 629 NAFLD cases were documented. After adjustment for potential confounders, an inverse association between total Mg intake and NAFLD odds was observed. Compared to participants in the lowest quintile of total Mg intake, the odds of NAFLD was 55% lower among individuals in the highest quintile [multivariable-adjusted odds ratio (OR) = 0.45, 95% confidence interval (CI) (0.23, 0.85), p for trend = 0.03]. Consistently, whole-grain consumption, a major dietary source of Mg, was inversely associated with NAFLD odds (p for trend = 0.02).

CONCLUSIONS

This study suggests that higher cumulative intake of Mg throughout adulthood is associated with lower odds of NAFLD in midlife. Future studies are needed to establish a possible causal relationship.

Non-alcoholic Steatohepatitis Pathogenesis, Diagnosis, and Treatment

There has been a rise in the prevalence of non-alcohol fatty liver disease (NAFLD) due to the popularity of western diets and sedentary lifestyles. One quarter of NAFLD patients is diagnosed with non-alcoholic steatohepatitis (NASH), with histological evidence not only of fat accumulation in hepatocytes but also of liver cell injury and death due to long-term inflammation. Severe NASH patients have increased risks of cirrhosis and liver cancer. In this review, we discuss the pathogenesis and current methods of diagnosis for NASH, and current status of drug development for this life-threatening liver disease.

Comprehensive analysis of the translatome reveals the relationship between the translational and transcriptional control in high fat diet-induced liver steatosis

Translational regulation plays a critical role in gene expression. However, there are few genome-wide studies on translational regulation in non-alcoholic fatty liver disease (NAFLD), which is a severe non-communicable epidemic worldwide. In this study, we performed RNC-mRNA (mRNAs bound to ribosome-nascent chain complex) sequencing and mRNA sequencing to probe the translation status of high-fat-diet (HFD) induced mouse fatty liver. Generally, in the HFD group compared to the control group, changes of translation ratios and changes in mRNA abundance had a negative correlation. The relative abundance of RNC-mRNAs and mRNAs were positively correlated, yet the former changed more slowly than the latter. However, the rate of change became more balanced when it came to the livers of mice that were fed the HFD plus lycopene, an antioxidant. This indicated relatively independent roles of translational modulation and transcriptional regulation. Furthermore, many genes were differentially regulated at the transcriptional or translational levels, suggesting a new screening strategy for functional genes. In conclusion, our analysis revealed the different and correlated role of translational control with transcriptional regulation in the HFD-induced mouse fatty liver relative to the control, which indicates critical roles of translational control for liver steatosis; thus, adding a new dimension towards a better understanding and improvement of treatment for NAFLD.

Lean NAFLD: an underrecognized and challenging disorder in medicine

Classically, Non-Alcoholic Fatty Liver Disease (NAFLD) has been thought to be driven by excessive weight gain and obesity. The overall greater awareness of this disorder has led to its recognition in patients with normal body mass index (BMI). Ongoing research has helped to better understand potential causes of Lean NAFLD, the risks for more advanced disease, and potential therapies. Here we review the recent literature on prevalence, risk factors, severity of disease, and potential therapeutic interventions.

Safety, tolerability, and pharmacokinetics of the novel pan-phosphodiesterase inhibitor ZSP1601 in healthy subjects: a double-blinded, placebo-controlled first-in-human single-dose and multiple-dose escalation and food effect study

Background: The pharmacokinetics (PK), safety, and tolerability profiles of ZSP1601, a first-in-class pan-phosphodiesterase (PDE) inhibitor, were evaluated in healthy Chinese volunteers.Research design and methods: This Phase 1a study consisted of a double-blinded, randomized, placebo-controlled single ascending dose (SAD) (25 to 350 mg), multiple ascending doses (MAD) (50 or 100 mg QD), and a two-period crossover food effect study (100 mg).Results: ZSP1601 was quickly absorbed, with maximum plasma concentrations (C_max) reached at 1.25 to 2.50 h (median T_max). The exposures exhibited dose-proportional increases, while the mean half-life (t1/2) ranged from 6.34-8.64 h. Steady-state was reached within seven days in the MAD study. The mean steady trough concentrations were 423 and 588 ng/mL, respectively. ZSP1601 accumulation was low, with ratios ≤ 1.5. The bioavailability of ZSP1601 was equivalent under fasted and fed states. All adverse events (AEs) were assessed as mild or moderate, with headaches as the most common. The highest single doses (275 and 350 mg) yielded more AEs, yet the rates were similar with the placebo cohorts in the MAD study.Conclusions: The safety and PK profiles of ZSP1601 support further efficacy evaluation in nonalcoholic steatohepatitis patients.Trial registration: The trial is registered at ClinicalTrials.gov (CT.gov identifier: NCT03392779).

α-Tocopherol suppresses hepatic steatosis by increasing CPT-1 expression in a mouse model of diet-induced nonalcoholic fatty liver disease

Aim

Antioxidant therapy for with vitamin E appears to be effective for the treatment of nonalcoholic fatty liver disease　(NAFLD). However, the mechanism of action and optimal therapeutic dosage is unclear. The present study was undertaken to examine whether the effects of α‐tocopherol (α‐Toc) on NAFLD are dose‐dependent in a diet‐induced obese model.

Methods

Male mice were fed standard chow, high‐fat (HF) diet, HF diet with low‐dose, or with high dose of α‐Toc supplementation. Histological findings, triglyceride content, and the levels of protein expression related to fatty acid synthesis/oxidation such as carnitine palmitoyltransferase I (CPT‐1) of liver were evaluated. In addition, 2‐tetradecylglycidic acid (TDGA), a CPT‐1 inhibitor, was administered to mice fed HF diet with low‐dose of α‐Toc. Finally, HepG2 cells in fat‐loaded environment were treated with 0–50 μM α‐Toc.

Results

Treatment of low‐dose of α‐Toc decreased HF‐induced hepatic fat accumulation, but this finding was not observed in treatment of high dose of α‐Toc. HF‐induced reduction of CPT‐1 was attenuated with low‐dose of α‐Toc but not with high dose of α‐Toc. TDGA suppressed the improvement of histological findings in liver induced by low‐dose of α‐Toc treatment. CPT‐1 expression in HepG2 cells increased in response to low‐dose of α‐Toc, but not in high dose.

Conclusions

Dual action of α‐Toc on CPT‐1 protein levels was observed. The effect of vitamin E on NAFLD may be not be dose‐dependent.

Impact of vitamin E on redox biomarkers in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disorder in Western nations and characterized by excessive accumulation of lipids in the liver. In this narrative review, we summarize the evidence from human trials that free radical-induced oxidation of macromolecules, in particular of lipids, is a characteristic feature of NAFLD and non-alcoholic steatohepatitis (NASH). We further synthesize the data in the scientific literature describing the impact of vitamin E (mainly α-tocopherol) on concentrations of redox biomarkers in liver biopsies from patients with NAFLD as well as animal experiments. In summary, the available evidence from clinical trials suggests that reactive species-mediated damage to macromolecules, predominantly lipids, occurs in NAFLD and NASH and that daily supplementation with at least 200 I.U. α-tocopherol may alleviate oxidative stress in the liver of NAFLD patients. We propose α-tocopherol as a useful model substance to identify and validate suitable redox biomarkers that may be employed in future clinical trials of new therapeutics for NAFLD.

Molecular Mechanisms That Link Oxidative Stress, Inflammation, and Fibrosis in the Liver

Activated hepatic stellate cells (HSCs) and myofibroblasts are the main producers of extracellular matrix (ECM) proteins that form the fibrotic tissue that leads to hepatic fibrosis. Reactive oxygen species (ROS) can directly activate HSCs or induce inflammation or programmed cell death, especially pyroptosis, in hepatocytes, which in turn activates HSCs and fibroblasts to produce ECM proteins. Therefore, antioxidants and the nuclear factor E2-related factor-2 signaling pathway play critical roles in modulating the profibrogenic response. The master proinflammatory factors nuclear factor-κB (NF-κB) and the nucleotide-binding oligomerization domain (NOD)-like receptor protein 3 (NLRP3) inflammasome may coordinate to produce and activate profibrogenic molecules such as interleukins 1β and 18, which effectively activate HSCs, to produce large amounts of fibrotic proteins. Furthermore, the NLRP3 inflammasome activates pro-caspase 1, which is upregulated by NF-κB, to produce caspase 1, which induces pyroptosis via gasdermin and the activation of HSCs. ROS play central roles in the activation of the NF-κB and NLRP3 signaling pathways via IκB (an inhibitor of NF-κB) and thioredoxin-interacting protein, respectively, thereby linking the molecular mechanisms of oxidative stress, inflammation and fibrosis. Elucidating these molecular pathways may pave the way for the development of therapeutic tools to interfere with specific targets.

Impact of Fasting Lipid Profile on Chronic Kidney Disease Patients Having Fatty Liver Disease

Background and objectives Chronic kidney disease (CKD) share a common pathophysiology with non-alcoholic fatty liver disease (NAFLD). This study aims to identify the lipid derangements in patients of CKD and to associate them with radiological evidence of NAFLD. Material and methods A cross-sectional observational study was performed in a tertiary care hospital, to include all chronic kidney disease patients (n=238) through non-probability consecutive sampling. The criteria for inclusion were baseline estimated Glomerular filtration rate (eGFR) below 60 ml/min/1.73m2 for at least three months and chronic renal parenchymal changes on ultrasound. Two study groups were identified based on ongoing hemodialysis, while two further study groups were identified based on radiological evidence of fatty liver disease. Results The mean age of the study population was 48.52 ± 9.44 years with no difference amongst hemodialysis status, females elder than males (p= 0.027), those with fatty liver were much younger (p=0.014), and the most common age group below 50 years (p=0.005) among the fatty liver group. Radiological evidence of NAFLD was found amongst two-third of the study group with the status of hemodialysis indifferent among the study population (p=0.436). The mean values amongst fatty liver versus non-fatty liver groups revealed high creatinine, alanine transaminase (ALT), high-density lipoprotein (HDL), triglycerides (TG), and very-low-density lipoprotein (VLDL) in the fatty liver group, low-density lipoprotein (LDL) and total cholesterol (TC) were indifferent amongst the groups, while LDL/HDL ratio was higher in the non-fatty liver group. Conclusion A significantly higher HDL was found in fatty liver associated with CKD as compared to the non-fatty liver group.

The pharmacological treatment of nonalcoholic fatty liver disease in children

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in childhood/adolescence. It comprises a broad spectrum of liver disease severity ranging from simple steatosis to steatohepatitis and fibrosis. To date lifestyle modifications, diet and physical activity represent the main option for the management of pediatric NAFLD, but numerous treatments classified depending on the mechanism of action, have been introduced. In keeping with, bariatric surgery, insulin sensitizers, antioxidants, probiotic and dietary supplementations have been evaluated in pediatric clinical trials.

AREAS COVERED

This review describes, after a search in PubMed/MEDLINE database, the current pediatric NAFLD non-pharmacological and pharmacological treatments and their effects on biochemical and histological features. We report not only the efficacy of the diet coupled with regular exercise but also advantages of the pharmacological treatments used in combination with lifestyle interventions in pediatric NAFLD.

EXPERT OPINION

Since pharmacological and non-pharmacological interventions have demonstrated variable effects in pediatric NAFLD, it is clear that safe and specific and efficient therapeutic strategies have not yet been identified. Therefore, large and long-term clinical trials in children are needed to find a way to reverse the liver tissue damage and the NAFLD-related long-term morbidity and mortality.

The transcontinental variability of nonalcoholic fatty liver disease

AIM

To compare the phenotype of lean versus overweight (OW) and obese (OB) subjects with non-alcoholic fatty liver disease (NAFLD) across multiple continents.

METHODS

A retrospective study of histologically defined subjects from a single center each in France (Fr), Brazil (Br), India (In) and United States (US) was performed.

RESULTS

A total of 70 lean [body mass index (BMI) < 25 kg/m²] subjects (Fr:Br:In:US: 16:19:22:13) with NAFLD were compared to 136 OW (BMI > 25 kg/m², BMI < 29 kg/m²) (n = 28:33:52:23) and 224 OB subjects (BMI > 29 kg/m²) (n = 81:11:22:103). Lean French subjects had the lowest incidence of type 2 diabetes while those from Brazil (P < 0.01) had the highest. Lean subjects had similar low-density lipoprotein-cholesterol, but higher high-density lipoprotein-cholesterol compared to obese subjects in all regions. In both lean and obese subjects, there were both insulin-sensitive and insulin-resistant subjects. Lean French subjects were most insulin-sensitive while those from Brazil were mostly insulin-resistant. For each weight category, subjects from India were more insulin-sensitive than those from other regions. Disease activity increased from lean to overweight to obese in France but was similar across weight categories in other regions.

CONCLUSION

The phenotype of NAFLD in lean subjects varies by region. Some obese subjects with NAFLD are insulin-sensitive. We hypothesize that genetics and region-specific disease modifiers account for these differences.

Vitamin E as an Adjuvant Treatment for Non-alcoholic Fatty Liver Disease in Adults: A Systematic Review of Randomized Controlled Trials

Nonalcoholic fatty liver disease (NAFLD) is one of the most common causes of chronic liver disease. It is characterized by a variety of pathologies, ranging from benign fatty liver to extensive fibrosis and even hepatocellular cancer. Among the several potential risk factors, insulin resistance and increased oxidative stress are the most important. Vitamin E is an antioxidant with a potential to be used as a treatment for NAFLD. Therefore, we carried out a structured systematic review of all RCTs conducted between 2010 and January 2020. After screening, eight RCTs were included. Our systematic review showed that vitamin E has clinical utility in improving biochemical (ALT and AST levels) and histological abnormalities in NAFLD (hepatic steatosis and lobular inflammation). However, vitamin E does not seem to have significant effects on liver fibrosis. Still, vitamin E has the potential to be used as an adjuvant for the treatment of NAFLD, and its use in clinical practice should be advocated.

Vitamin E does not prevent Western diet-induced NASH progression and increases metabolic flux dysregulation in mice

Fatty liver involves ectopic lipid accumulation and dysregulated hepatic oxidative metabolism, which can progress to a state of elevated inflammation and fibrosis referred to as nonalcoholic steatohepatitis (NASH). The factors that control progression from simple steatosis to NASH are not fully known. Here, we tested the hypothesis that dietary vitamin E (VitE) supplementation would prevent NASH progression and associated metabolic alterations induced by a Western diet (WD). Hyperphagic melanocortin-4 receptor-deficient (MC4R^-/-) mice were fed chow, chow+VitE, WD, or WD+VitE starting at 8 or 20 weeks of age. All groups exhibited extensive hepatic steatosis by the end of the study (28 weeks of age). WD feeding exacerbated liver disease severity without inducing proportional changes in liver triglycerides. Eight weeks of WD accelerated liver pyruvate cycling, and 20 weeks of WD extensively upregulated liver glucose and oxidative metabolism assessed by ²H/¹³C flux analysis. VitE supplementation failed to reduce the histological features of NASH. Rather, WD+VitE increased the abundance and saturation of liver ceramides and accelerated metabolic flux dysregulation compared with 8 weeks of WD alone. In summary, VitE did not limit NASH pathogenesis in genetically obese mice, but instead increased some indicators of metabolic dysfunction.

Chitosan Oligosaccharide Ameliorates Nonalcoholic Fatty Liver Disease (NAFLD) in Diet-Induced Obese Mice

Nonalcoholic fatty liver disease (NAFLD) is a global epidemic, and there is no standard and efficient therapy for it. Chitosan oligosaccharide (COS) is widely known to have various biological effects, and in this study we aimed to evaluate the liver-protective effect in diet-induced obese mice for an enzymatically digested product of COS called COS23 which is mainly composed of dimers and trimers. An integrated analysis of the lipidome and gut microbiome were performed to assess the effects of COS23 on lipids in plasma and the liver as well as on intestinal microbiota. Our results revealed that COS23 obviously attenuated hepatic steatosis and ameliorated liver injury in diet-induced obese mice. The hepatic toxic lipids—especially triglycerides (TGs) and free fatty acids (FFAs)—were decreased dramatically after COS23 treatment. COS23 regulated lipid-related pathways, especially inhibiting the expressions of FFA-synthesis-related genes and inflammation-related genes. Furthermore, COS23 could alter lipid profiles in plasma. More importantly, COS23 also decreased the abundance of Mucispirillum and increased the abundance of Coprococcus in gut microbiota and protected the intestinal barrier by up-regulating the expression of tight-junction-related genes. In conclusion, COS23, an enzymatically digested product of COS, might serve as a promising candidate in the clinical treatment of NAFLD.

Mitochondria-Mediated Pathogenesis and Therapeutics for Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) has become a worldwide epidemic over the last decade. Remarkable progress has been made in understanding the pathogenesis of NAFLD and, subsequently, in developing medications to treat this disease. Although the mechanisms of NAFLD are complex and multifactorial, accumulating and emerging evidence indicates that mitochondria play a critical role in the pathogenesis and progression of NAFLD. Pharmacologic therapies acting on mitochondria may therefore pave the way to novel strategies for the prevention and protection against NAFLD. This review focuses on new insights into the role of hepatic mitochondrial dysfunction in NAFLD, and summarizes recent studies on mitochondria-centric therapies for NAFLD utilizing new medications or repurposing of currently available drugs. Although some studies presented may feature controversial results or are still in lack of clinical verification, it is undoubted that medications that may spare the mitochondria from multiple levels of damage are highly promising, and have begun to be used with some degree of success.

Treatment options for nonalcoholic fatty liver disease: a double-blinded randomized placebo-controlled trial

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide and is becoming the most frequent indication of liver transplantation. Cardiovascular disease is the main cause of death in these patients. There is no Food and Drug Association-approved medication for NAFLD patients. We aimed to provide more robust evidence on the use of medications that are inexpensive and available, namely, metformin, silymarin, pioglitazone, and vitamin E, for treating NAFLD.

MATERIALS AND METHODS

We conducted a randomized double-blinded, placebo-controlled trial on 150 consecutive patients with NAFLD who were assigned to five groups: lifestyle plus placebo, metformin 500 mg/day, silymarin 140 mg/day, pioglithasone 15 mg/day, and vitamin E 400 IU/day, all for 3 months. Anthropometric and biochemical variables were measured at baseline and 3 months later.

RESULTS

The mean age of the patients was 47.0±9.1 (range: 18-65) years and the sex distribution was 73 (48.7%) women and 77 (51.3%) men. Patients in all groups showed a significant improvement in anthropometric parameters such as waist circumference and BMI. There was no statistically significant difference in alanine transaminase and aspartate transaminase in the control group after treatment (P=0.51, 0.18, respectively); however, both liver enzymes decreased significantly in the other groups.

DISCUSSION AND CONCLUSION

This randomized double-blinded placebo-controlled clinical trial suggested a significant benefit of silymarin, pioglitazone, and vitamin E in improving liver aminotransferases in patients with NAFLD after only 3 months, without exerting any specific side effects.

The impact of turmeric or its curcumin extract on nonalcoholic fatty liver disease: a systematic review of clinical trials

Background:

Turmeric and its curcumin extract have been evaluated in patients with nonalcoholic fatty liver disease (NAFLD), a common ailment that can lead to irreparable liver damage.

Objective:

To identify the evidence supporting the use of turmeric or curcumin therapy in NAFLD.

Methods:

We searched PubMed, EMBASE, and Cochrane Central from the earliest possible date to 12/17/18 including terms for turmeric, curcumin, and NAFLD. We assessed the impact of turmeric or its curcumin extract on alanine transaminase (ALT), aspartate transaminase (AST), and NAFLD severity via ultrasound.

Results:

Five trials assessed the comparative efficacy of curcumin/turmeric in NAFLD. One trial was single armed with comparisons only versus baseline and another trial was only available in abstract form. All of the trials had small sample sizes, 4 of 5 trials had limited durations of follow-up, and all trials had methodological limitations that negatively impacted the strength and applicability of evidence. Clinical and methodological heterogeneity precluded statistical pooling. Three of the 4 trials with evaluable data for turmeric or curcumin versus their own baseline demonstrated significant reductions in ALT, AST, and NAFLD severity grade. Two of the 4 placebo controlled trials had significant mean difference reductions in ALT and AST for turmeric or curcumin versus placebo while 2 of 3 of these trials found significant reductions in NAFLD severity grade. Among these trials, only one used turmeric instead of a curcumin extract and this turmeric trial did not demonstrate any differences in ALT, AST, or NAFLD severity between the turmeric and placebo groups.

Conclusions:

Curcumin extract is a promising, but not proven, treatment for NAFLD while the role for turmeric is less clear. The general findings are that ALT, AST and NAFLD severity are reduced with the use of curcumin.

Role of vitamin E in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide. NAFLD manifests as hepatic lipid accumulation, insulin resistance, and inflammation, and can progress to nonalcoholic steatohepatitis (NASH) and cirrhosis. However, the underlying mechanisms of NAFLD, including those that drive its progression, are unclear. Both liver-resident (Kupffer cells) and recruited macrophages play a crucial role in the development of insulin resistance and NASH. Therefore, NALFD could potentially be ameliorated by modifying the polarization of macrophages/Kupffer cells. Reactive oxygen species induce oxidative stress, which is implicated in the progression of NASH. Micronutrients, including vitamins, are potent antioxidants that exert anti-inflammatory effects, and are used in the treatment of NAFLD. We review here the molecular mechanisms of the pathogenesis of NAFLD and the potential utility of vitamin E in its prevention and/or treatment. © 2018 IUBMB Life, 71(4):516-522, 2019.

Advances and challenges in the management of advanced fibrosis in nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is rapidly becoming the most common type of chronic liver disease worldwide. From the spectrum of NAFLD, it is nonalcoholic steatohepatitis (NASH) that predominantly predisposes patients to higher risk for development of cirrhosis and hepatocellular carcinoma. There is growing evidence that the risk of progression to cirrhosis and hepatocellular carcinoma is not uniform among all patients with NASH. In fact, NASH patients with increasing numbers of metabolic diseases such as diabetes, hypertension, visceral obesity and dyslipidemia are at a higher risk of mortality. Additionally, patients with higher stage of liver fibrosis are also at increased risk of mortality. In this context, NASH patients with fibrosis are in the most urgent need of treatment. Also, the first line of treatment for NASH is lifestyle modification with diet and exercise. Nevertheless, the efficacy of lifestyle modification is quite limited. Additionally, vitamin E and pioglitazone may be considered for subset of patients with NASH. There are various medications targeting one or more steps in the pathogenesis of NASH being developed. These drug regimens either alone or in combination, may provide potential treatment option for patients with NASH.

Vitamin E alleviates non-alcoholic fatty liver disease in phosphatidylethanolamine N-methyltransferase deficient mice

Phosphatidylethanolamine N-methyltransferase (PEMT) converts phosphatidylethanolamine (PE) to phosphatidylcholine (PC), mainly in the liver. Pemt^-/- mice are protected from high-fat diet (HFD)-induced obesity and insulin resistance, but develop severe non-alcoholic fatty liver disease (NAFLD) when fed a HFD, mostly due to impaired VLDL secretion. Oxidative stress is thought to be an essential factor in the progression from simple steatosis to steatohepatitis. Vitamin E is an antioxidant that has been clinically used to improve NAFLD pathology. Our aim was to determine whether supplementation of the diet with vitamin E could attenuate HFD-induced hepatic steatosis and its progression to NASH in Pemt^-/- mice. Treatment with vitamin E (0.5 g/kg) for 3 weeks improved VLDL-TG secretion and normalized cholesterol metabolism, but failed to reduce hepatic TG content. Moreover, vitamin E treatment was able to reduce hepatic oxidative stress, inflammation and fibrosis. We also observed abnormal ceramide metabolism in Pemt^-/- mice fed a HFD, with elevation of ceramides and other sphingolipids and higher expression of mRNAs for acid ceramidase (Asah1) and ceramide kinase (Cerk). Interestingly, vitamin E supplementation restored Asah1 and Cerk mRNA and sphingolipid levels. Together this study shows that vitamin E treatment efficiently prevented the progression from simple steatosis to steatohepatitis in mice lacking PEMT.

A detailed guide to lipid therapy in intestinal failure

Intravenous lipid emulsions are an integral part of nutrition therapy in the intestinal failure patient. In addition to being a concentrated source of non-protein calories, they provide the essential fatty acids necessary for growth and development. Depending upon the oil source used in these products, complications such as intestinal failure associated liver disease (IFALD) can occur. This review will discuss the risks and benefits associated with these products, especially as they relate to the pediatric intestinal failure patient.

Fish oil-derived lipid emulsion induces RIP1-dependent and caspase 8-licensed necroptosis in IEC-6 cells through overproduction of reactive oxygen species

BACKGROUND

Excessive cell death of enterocytes has been demonstrated to be partially associated with the intravenously-administrated lipid emulsions (LEs) during parenteral nutrition (PN) support. However, as a new generation of LE, the effect of fish oil-derived lipid emulsion (FOLE) on the death of enterocytes remains elusive.

METHODS

Intestinal epithelial cells (IEC-6 cell line) were treated with FOLE (0.25-1%) for 24 h. Cell survival was measured by CCK-8 assay, and morphological changes were monitored by time-lapse live cell imaging. The expression of receptor-interacting protein 1/3 (RIP1/3) and caspase 8 was assessed by westernblot, and the formation of necrosome (characterized by the assembly of RIP1/3 complex along with the dissociation of caspase 8) was examined by immunoprecipitation. Additionally, the production of intracellular reactive oxygen species (ROS) was detected by using a ROS detection kit with an oxidation-sensitive probe (DCFH-DA).

RESULTS

FOLE dose-dependently induced non-apoptotic, but programmed necroctic cell death (necroptosis) within 4-8 h after treatment. The assembly of RIP1/3 complex along with the dissociation of caspase 8 from RIP1 was observed in FOLE-treated cells. Moreover, FOLE-induced cell death was significantly alleviated by inhibiting RIP1, and was further aggravated by inhibiting caspase 8. In addition, prior to cell death the accumulation of intracellular ROS was significantly increased in FOLE-treated cells (increased by approximately 5-fold versus control, p < 0.001), which could be attenuated by inhibiting RIP1 (decreased by approximately 35% versus FOLE, p < 0.05).

CONCLUSIONS

FOLE induces RIP1-dependent and caspase 8-licensed necroptosis through overproduction of ROS in vitro. Our findings may provide novel insights into the clinical applications of FOLE during PN support.

Nonalcoholic fatty liver disease in patients with psoriasis: a consequence of systemic inflammatory burden?

Patients with psoriasis are at an increased risk for nonalcoholic fatty liver disease (NAFLD) compared with the general population. However, the pathophysiology underlying this comorbidity and elucidation of effective treatment strategies are unclear. This review provides insights into the possible role of chronic, low-grade inflammation in the pathogenesis of NAFLD in patients with psoriasis. Both conditions are associated with increased levels of proinflammatory adipokines (such as tumour necrosis factor-α and interleukin-6) and hepatokines, and decreased levels of adiponectin, an anti-inflammatory adipokine. This imbalance in inflammatory mediators could result in insulin resistance and, thereby, facilitate the occurrence and progression of NAFLD in a multistep manner. All patients with psoriasis should, therefore, be considered candidates for NAFLD screening and managed accordingly. Given the common aetiology of inflammation between these conditions, it is hypothesized that biological therapies for psoriasis may attenuate the systemic inflammatory process and progression of NAFLD in patients with psoriasis.

Long noncoding RNA H19 interacts with polypyrimidine tract-binding protein 1 to reprogram hepatic lipid homeostasis

H19 is an imprinted long noncoding RNA abundantly expressed in embryonic liver and repressed after birth. We show that H19 serves as a lipid sensor by synergizing with the RNA-binding polypyrimidine tract-binding protein 1 (PTBP1) to modulate hepatic metabolic homeostasis. H19 RNA interacts with PTBP1 to facilitate its association with sterol regulatory element-binding protein 1c mRNA and protein, leading to increased stability and nuclear transcriptional activity. H19 and PTBP1 are up-regulated by fatty acids in hepatocytes and in diet-induced fatty liver, which further augments lipid accumulation. Ectopic expression of H19 induces steatosis and pushes the liver into a "pseudo-fed" state in response to fasting by promoting sterol regulatory element-binding protein 1c protein cleavage and nuclear translocation. Deletion of H19 or knockdown of PTBP1 abolishes high-fat and high-sucrose diet-induced steatosis.

CONCLUSION

Our study unveils an H19/PTBP1/sterol regulatory element-binding protein 1 feedforward amplifying signaling pathway to exacerbate the development of fatty liver. (Hepatology 2018;67:1768-1783).

Effects of Chinese Medicinal Formula BNG-1 on Phosphodiesterase 3B Expression, Hepatic Steatosis, and Insulin Resistance in High Fat Diet-induced NAFLD Mice

Background: Chinese medicinal formula BNG-1, a non-specific inhibitor of phospho-diesterases (PDEs), can be considered as a potential anti-inflammatory agent. The present study was aimed at determining the effects of BNG-1 on the development of non-alcoholic fatty liver disease (NAFLD) in mice. Design and Methods: Male CD1 mice were randomly divided into seven groups, the control Con (4) and Con (8)+saline groups were fed a standard control diet for four or eight weeks; the experimental HFD (4) and HFD (8)+saline groups were fed a high fat diet for four or eight weeks; the HFD (8)+LBNG, HFD (8)+MBNG, and HFD (8)+HBNG groups received a high fat diet along with low, moderate or high doses of BNG-1 (0.026, 0.035, and 0.052g/30g body weight) which was administered for the last four weeks of an eight-week experimental period. After the end of experiment, blood and tissue samples were taken and analyzed. Results: Mice in the HFD (4) group had higher levels of alanine aminotransferase (ALT), plasma and hepatic triglyceride and cholesterol, and homeostasis model assessment-estimated insulin resistance (HOMA-IR) compared with mice in the Con (4) group. Mice receiving the high fat diet along with the BNG-1 supplement had decreased body weight gains and lower visceral fat weights compared with the HFD (8)+saline group. They had also significantly reduced levels of abnormal ALT and HOMA-IR, and improved blood lipid profile. BNG-1-treated mice exhibited reduced hepatic lipid accumulation, lower oxidative stress, and decreased expression of pro-inflammatory cytokines (TNF-α and IL-1β). Furthermore, BNG-1 treatment resulted in down-regulation of hepatic cyclic-AMP dependent PDE3B and up-regulation of PDE3B expression in epididymis adipose tissue. Conclusions: BNG-1 mediated changes in PDE3B expression along with reduction in oxidative stress and inflammation. BNG-1 may ameliorate insulin resistance and hepatic steatosis in the NAFLD mouse model.

Treatment Strategies for Nonalcoholic Fatty Liver Disease and Nonalcoholic Steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is recognized as a global health problem and as a common cause of chronic liver disease. Nonalcoholic steatohepatitis (NASH) carries an increased risk for development of advanced liver disease. Lifestyle modifications with diet and exercise have been the initial management recommendation. However, these changes are difficult to achieve and sustain overtime. There are pharmacologic agents being considered for treatment of NASH. Some target insulin resistance and others focus on oxidative stress, inflammation, apoptosis, and fibrosis. There is a great deal of efforts to develop therapeutic regimens for patients with NASH and NASH with significant fibrosis.

Association of Vitamin E Levels with Metabolic Syndrome, and MRI-Derived Body Fat Volumes and Liver Fat Content

We aimed to relate circulating α- and γ-tocopherol levels to a broad spectrum of adiposity-related traits in a cross-sectional Northern German study. Anthropometric measures were obtained, and adipose tissue volumes and liver fat were quantified by magnetic resonance imaging in 641 individuals (mean age 61 years; 40.6% women). Concentrations of α- and γ-tocopherol were measured using high performance liquid chromatography. Multivariable-adjusted linear and logistic regression were used to assess associations of circulating α- and γ-tocopherol/cholesterol ratio levels with visceral (VAT) and subcutaneous adipose tissue (SAT), liver signal intensity (LSI), fatty liver disease (FLD), metabolic syndrome (MetS), and its individual components. The α-tocopherol/cholesterol ratio was positively associated with VAT (β scaled by interquartile range (IQR): 0.036; 95%Confidence Interval (CI): 0.0003; 0.071) and MetS (Odds Ratio (OR): 1.83; 95% CI: 1.21–2.76 for 3rd vs. 1st tertile), and the γ-tocopherol/cholesterol ratio was positively associated with VAT (β scaled by IQR: 0.066; 95% CI: 0.027; 0.104), SAT (β scaled by IQR: 0.048; 95% CI: 0.010; 0.087) and MetS (OR: 1.87; 95% CI: 1.23–2.84 for 3rd vs. 1st tertile). α- and γ-tocopherol levels were positively associated with high triglycerides and low high density lipoprotein cholesterol levels (all P_trend < 0.05). No association of α- and γ-tocopherol/cholesterol ratio with LSI/FLD was observed. Circulating vitamin E levels displayed strong associations with VAT and MetS. These observations lay the ground for further investigation in longitudinal studies.