Natural History of Simple Steatosis or Nonalcoholic Fatty Liver

Exosome prospects in the diagnosis and treatment of non-alcoholic fatty liver disease

The growing prevalence of NAFLD and its global health burden have provoked considerable research on possible diagnostic and therapeutic options for NAFLD. Although various pathophysiological mechanisms and genetic factors have been identified to be associated with NAFLD, its treatment remains challenging. In recent years, exosomes have attracted widespread attention for their role in metabolic dysfunctions and their efficacy as pathological biomarkers. Exosomes have also shown tremendous potential in treating a variety of disorders. With increasing evidence supporting the significant role of exosomes in NAFLD pathogenesis, their theragnostic potential has become a point of interest in NAFLD. Expectedly, exosome-based treatment strategies have shown promise in the prevention and amelioration of NAFLD in preclinical studies. However, there are still serious challenges in preparing, standardizing, and applying exosome-based therapies as a routine clinical option that should be overcome. Due to the great potential of this novel theragnostic agent in NAFLD, further investigations on their safety, clinical efficacy, and application standardization are highly recommended.

The impact of metabolic syndrome severity on racial and ethnic disparities in Metabolic Dysfunction-Associated Steatotic Liver Disease

BACKGROUND & AIMS

Previous studies have examined the effects of metabolic syndrome (MetS) rather than its severity on race and ethnic disparities in Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD). We used the MetS severity score, a validated sex-race-ethnicity-specific severity measure, to examine the effects of race/ethnicity on the association between MetS severity and MASLD.

METHODS

This study included 10,605 adult participants from the Third National Health and Nutrition Examination Survey. The MASLD diagnosis was based on ultrasound findings in patients without excessive alcohol intake or other liver diseases. MetS severity Z-scores were calculated and stratified into four categories low (1st-50th), moderate (>50th-75th), high (>75th-90th), and very high (>90th+)]. Multivariable adjusted logistic regression models with complex survey methods were used to test the effect of MetS severity on MASLD.

RESULTS

The age-adjusted MASLD prevalence was 17.4%, 25.7%, 42.5, and 54.9% in adults with mild, moderate, high, and very high MetS severities, respectively (P-trend <0.001). MetS severity was significantly higher in patients with MASLD than in those without [mean percentile 60th vs. 44th, P<0.001]. Among patients with MASLD, Mexican-American and Black non-Hispanic females had significantly higher age-adjusted MetS severity (68th and 61st, respectively) than White non-Hispanic females 54th, while Black non-Hispanic males had significantly lower MetS severity (56th) than White non-Hispanic males (70th) (P-Interaction = 0.02). Adults with high and very high MetS severity had 2.27 (95% CI:1.70 to 3.03) and 3.12 (95% CI:2.20 to 4.42), respectively, higher adjusted odds of MASLD than those with mild MetS severity.

CONCLUSIONS

Racial/ethnic disparities in MetS severity play a pivotal role in the risk of MASLD. Our findings highlight the potential clinical utility of the MetS severity score in identifying at-risk individuals, which will help guide targeted prevention and tailoring management strategies to mitigate the MASLD burden.

Multispecies transcriptomics identifies SIKE as a MAPK repressor that prevents NASH progression

Nonalcoholic fatty liver (NAFL) remains relatively benign, but high-risk to end-stage liver diseases become highly prevalent when it progresses into nonalcoholic steatohepatitis (NASH). Our current understanding of the development of NAFL to NASH remains insufficient. In this study, we revealed MAP kinase (MAPK) activation as the most notable molecular signature associated with NASH progression across multiple species. Furthermore, we identified suppressor of IKKε (SIKE) as a conserved and potent negative controller of MAPK activation. Hepatocyte-specific overexpression of Sike prevented NASH progression in diet- and toxin-induced mouse NASH models. Mechanistically, SIKE directly interacted with TGF-β-activated kinase 1 (TAK1) and TAK1-binding protein 2 (TAB2) to interrupt their binding and subsequent TAK1-MAPK signaling activation. We found that indobufen markedly up-regulated SIKE expression and effectively improved NASH features in mice and macaques. These findings identify SIKE as a MAPK suppressor that prevents NASH progression and provide proof-of-concept evidence for targeting the SIKE-TAK1 axis as a potential NASH therapy.

Advances in obesity pharmacotherapy; learning from metabolic surgery and beyond

Currently, metabolic surgery (MS) constitutes the most effective means for durable weight loss of clinically meaningful magnitude, type 2 diabetes remission and resolution of non-alcoholic steatohepatitis, as well as other obesity-related comorbidities. Accumulating evidence on the mechanisms through which MS exerts its actions has highlighted the altered secretion of hormonally active peptides of intestinal origin with biological actions crucial to energy metabolism as key drivers of MS clinical effects. The initial success of glucagon-like peptide-1 (GLP-1) receptor agonists regarding weight loss and metabolic amelioration have been followed by the development of unimolecular dual and triple polyagonists, additionally exploiting the effects of glucagon and/or glucose-dependent insulinotropic polypeptide (GIP) which achieves a magnitude of weight loss approximating that of common MS operations. Through the implementation of such therapies, the feasibility of a "medical bypass", namely the replication of the clinical effects of MS through non-surgical interventions may be foreseeable in the near future. Apart from weight loss, this approach ought to be put to the test also regarding other clinical outcomes, such as liver steatosis and steatohepatitis, cardiovascular disease, and overall prognosis, on which MS has a robustly demonstrated impact. Besides, a medical bypass as an alternative, salvage, or combination strategy to MS may promote precision medicine in obesity therapeutics.

Gossypetin Prevents the Progression of Nonalcoholic Steatohepatitis by Regulating Oxidative Stress and AMP-Activated Protein Kinase

Nonalcoholic steatohepatitis (NASH) is a severe liver metabolic disorder, however, there are still no effective and safe drugs for its treatment. Previous clinical trials used various therapeutic approaches to target individual pathologic mechanisms, but these approaches were unsuccessful because of the complex pathologic causes of NASH. Combinatory therapy in which two or more drugs are administered simultaneously to patients with NASH, however, carries the risk of side effects associated with each individual drug. To solve this problem, we identified gossypetin as an effective dual-targeting agent that activates AMP-activated protein kinase (AMPK) and decreases oxidative stress. Administration of gossypetin decreased hepatic steatosis, lobular inflammation and liver fibrosis in the liver tissue of mice with choline-deficient high-fat diet and methionine-choline deficient diet (MCD) diet-induced NASH. Gossypetin functioned directly as an antioxidant agent, decreasing hydrogen peroxide and palmitate-induced oxidative stress in the AML12 cells and liver tissue of MCD diet-fed mice without regulating the antioxidant response factors. In addition, gossypetin acted as a novel AMPK activator by binding to the allosteric drug and metabolite site, which stabilizes the activated structure of AMPK. Our findings demonstrate that gossypetin has the potential to serve as a novel therapeutic agent for nonalcoholic fatty liver disease /NASH. SIGNIFICANCE STATEMENT: This study demonstrates that gossypetin has preventive effect to progression of nonalcoholic steatohepatitis (NASH) as a novel AMP-activated protein kinase (AMPK) activator and antioxidants. Our findings indicate that simultaneous activation of AMPK and oxidative stress using gossypetin has the potential to serve as a novel therapeutic approach for nonalcoholic fatty liver disease /NASH patients.

Lean Indian patients with non-alcoholic fatty liver disease (NAFLD) have less metabolic risk factors but similar liver disease severity as non-lean patients with NAFLD

INTRODUCTION

Although most patients with NAFLD are obese or overweight, some are lean with normal BMI. Our aim was to assess differences in clinicopathological profile and liver disease severity among lean and non-lean NAFLD.

METHODS

Data of 1040 NAFLD patients over last 10 years was analysed. BMI < 23 kg/m2 categorised lean patients. Non-invasive assessment of steatosis was done by ultrasound and controlled attenuation parameter (CAP) while fibrosis was assessed with FIB-4 and liver stiffness measurement (LSM). FibroScan-AST (FAST) score was used for non-invasive prediction of NASH with significant fibrosis. Histology was reported using NASH-CRN system.

RESULTS

149 (14.3%) patients were lean while 891 (85.7%) patients were non-lean. Diabetes mellitus [25 (16.7%) vs 152 (17.05%), p > 0.99], elevated triglycerides [81 (54.3%) vs 525 (58.9%), p = 0.33] and low HDL [71(47.6%) vs 479(53.7%), p = 0.18] were observed in a similar proportion. Lean patients were less likely to have central obesity [72 (48.3%) vs 788 (88.4%), p < 0.001], hypertension [16 (10.7%) vs 239(26.8%), p < 0.001] and metabolic syndrome [21 (14.09%) vs 290 (32.5%), p < 0.001]. No difference in steatosis assessment was noted using ultrasound (p = 0.55) or CAP (0.11). FAST [0.38 (0.18-0.66) vs 0.39 (0.27-0.73), p = 0.53], FIB-4 [1.08 (0.65-1.91) vs 1.09 (0.66-1.94), p = 0.94] and LSM [6.1 (4.8-7.9) vs 6.2 (4.7-8.6), p = 0.19) were similar. Liver biopsy was available in 149 patients [lean: 19 (12.7%), non-lean: 130 (87.3%)]. There was no difference in the number of patients with NASH [4 (21.05%) vs 20 (15.3%), p = 0.51], significant fibrosis [2 (10.5%) vs 32 (24.6%), p = 0.25] or advanced fibrosis [1 (5.26%) vs 18 (13.84%), p = 0.47].

CONCLUSION

Although metabolic co-morbidities are less common, there is no difference in liver disease severity among both groups.

Inflammation and Digestive Cancer

Chronic inflammation is linked to carcinogenesis, particularly in the digestive organs, i.e., the stomach, colon, and liver. The mechanism of this effect has, however, only partly been focused on. In this review, we focus on different forms of chronic hepatitis, chronic inflammatory bowel disease, and chronic gastritis, conditions predisposing individuals to the development of malignancy. Chronic inflammation may cause malignancy because (1) the cause of the chronic inflammation is itself genotoxic, (2) substances released from the inflammatory cells may be genotoxic, (3) the cell death induced by the inflammation induces a compensatory increase in proliferation with an inherent risk of mutation, (4) changes in cell composition due to inflammation may modify function, resulting in hormonal disturbances affecting cellular proliferation. The present review focuses on chronic gastritis (Helicobacter pylori or autoimmune type) since all four mechanisms may be relevant to this condition. Genotoxicity due to the hepatitis B virus is an important factor in hepatocellular cancer and viral infection can similarly be central in the etiology and malignancy of inflammatory bowel diseases. Helicobacter pylori (H. pylori) is the dominating cause of chronic gastritis and has not been shown to be genotoxic, so its carcinogenic effect is most probably due to the induction of atrophic oxyntic gastritis leading to hypergastrinemia.

Effects of ozone exposure on lipid metabolism in Huh-7 human hepatoma cells

Ozone pollution is a major environmental concern. According to recent epidemiological studies, ozone exposure increases the risk of metabolic liver disease. However, studies on the mechanisms underlying the effects of ozone exposure on hepatic oxidative damage, lipid synthesis, and catabolism are limited. In this study, Huh-7 human hepatocellular carcinoma cells were randomly divided into five groups and exposed to 200 ppb O₃ for 0, 1, 2, 4, and 8 h. We measured the levels of oxidative stress and analyzed the changes in molecules related to lipid metabolism. The levels of oxidative stress were found to be significantly elevated in Huh-7 hepatocellular carcinoma cells after O₃ exposure. Moreover, the expression levels of intracellular lipid synthases, including SREBP1, FASN, SCD1, and ACC1, were enhanced. Lipolytic enzymes, including ATGL and HSL, and the mitochondrial fatty acid oxidase, CPT1α, were inhibited after O₃ exposure. In addition, short O₃ exposure enhanced the expression of the intracellular peroxisomal fatty acid β-oxidase, ACOX1; however, its expression decreased adaptively with longer exposure times. Overall, O₃ exposure induces an increase in intracellular oxidative stress and disrupts the normal metabolism of lipids in hepatocytes, leading to intracellular lipid accumulation.

Prevalence and Characteristics of Nonalcoholic Fatty Liver Disease and Fibrosis in People Living With HIV Monoinfection: A Systematic Review and Meta-analysis

BACKGROUND AND AIMS

Liver disease remains a leading cause of morbidity and mortality among people living with HIV (PLWH). Emerging data suggest that PLWH are at high risk for developing nonalcoholic fatty liver disease (NAFLD). The aim of this review is to examine the current literature and provide an accurate estimate of the prevalence of NAFLD, nonalcoholic steatohepatitis (NASH), and fibrosis, and identify potential risk factors for NAFLD in PLWH.

METHODS

We searched PubMed and Embase databases to identify studies reporting the prevalence of NAFLD and/or fibrosis in PLWH monoinfection. We performed a random effects meta-analysis of proportions to estimate the pooled prevalence of NAFLD, NASH, and fibrosis among PLWH monoinfection. We also examined potential risk factors for NAFLD by comparing characteristics of PLWH monoinfection with and without NAFLD.

RESULTS

A total of 43 studies, reporting data for 8230 patients, met our eligibility criteria and were included in the meta-analysis. Based on imaging studies the overall pooled prevalence of NAFLD and moderate liver fibrosis (METAVIR ≥ F2) among PLWH monoinfection was 33.9% (95% confidence interval [CI], 29.67%-38.39%), and 12.00% (95% CI, 10.02%-14.12%), respectively. Based on biopsy studies, prevalence of NASH and significant liver fibrosis (stage ≥F2 on histology) was 48.77% (95% CI, 34.30%-63.34%) and 23.34% (95% CI, 14.98%-32.75%), respectively. Traditional metabolic syndrome and HIV-related factors were associated with NAFLD in PLWH.

CONCLUSIONS

Our study confirms that the burden of NAFLD, NASH, and fibrosis is high among PLWH monoinfection. Prospective longitudinal studies are needed to delineate NAFLD, NASH, and fibrosis risk factors, and identify early interventions and new therapies for NAFLD in this population.

Histological features of non-alcoholic fatty liver disease revealed in response to mixed vehicle emission exposure and consumption of a high-fat diet in wildtype C57Bl/6 male mice

Non-alcoholic fatty liver disease (NAFLD) is currently plaguing the population at pandemic proportions and is expected to become more prevalent over the next decade. Recent epidemiological studies have demonstrated a correlation between the manifestation of NAFLD and ambient air pollution levels, which is exacerbated by other risk factors, such as diabetes, dyslipidemia, obesity, and hypertension. Exposure to airborne particulate matter has also been associated with inflammation, hepatic lipid accumulation, oxidative stress, fibrosis, and hepatocyte injury. While prolonged consumption of a high-fat (HF) diet is associated with NAFLD, little is known regarding the effects of inhaled traffic-generated air pollution, a ubiquitous environmental pollutant, on the pathogenesis of NAFLD. Therefore, we investigated the hypothesis that exposure to a mixture of gasoline and diesel engine emissions (MVE), coupled with the concurrent consumption of a HF diet, promotes the development of a NAFLD phenotype within the liver. Three-month-old male C57Bl/6 mice were placed on either a low-fat or HF diet and exposed via whole-body inhalation to either filtered (FA) air or MVE (30 µg PM/m³ gasoline engine emissions + 70 µg PM/m³ diesel engine emissions) 6 hr/day for 30 days. Histology revealed mild microvesicular steatosis and hepatocyte hypertrophy in response to MVE exposure alone, compared to FA controls, yielding a classification of "borderline NASH" under the criteria of the modified NAFLD active score (NAS) system. As anticipated, animals on a HF diet exhibited moderate steatosis; however, we also observed inflammatory infiltrates, hepatocyte hypertrophy, and increased lipid accumulation, with the combined effect of HF diet and MVE exposure. Our results indicate that inhalation exposure to traffic-generated air pollution initiates hepatocyte injury and further exacerbates lipid accumulation and hepatocyte injury induced by the consumption of a HF diet, thereby contributing to the progression of NAFLD-related pathologies.

Hepatotoxicity of polymeric proanthocyanidins is caused by translocation of bacterial lipopolysaccharides through impaired gut epithelium

Polymeric proanthocyanidins (P-PAC) induced hepatotoxicity in C57BL/6 mice. Mice were supplemented with P-PAC alone or with a mixture of probiotic bacteria (PB), Lactobacillus, Bifidobacterium, and Akkermansia muciniphila for 14 consecutive days. The liver tissues of sacrificed mice were analyzed by mass spectrometry to identify and quantify the P-PAC metabolites. Potential P-PAC metabolites, 2-hydroxyphenylacetic acid and pyrocatechol were detected in higher concentrations and 4-hydroxybenzoic acid was detected exclusively in the mice supplemented with P-PAC and PB. Supplementation with P-PAC alone or with PB caused no shift in the α-diversity of mice gut microbiota. P-PAC induced nonalcoholic steatohepatitis in mice through increasing liver exposure to intestinal bacterial lipopolysaccharides by reducing expression of gut epithelial tight junction proteins, claudin-3 and occludin. Lipopolysaccharide concentrations in the livers of mice supplemented with P-PAC were significantly high compared to the control mice. Furthermore, P-PAC downregulated the expressions of claudin-3 and claudin-4 tight junction proteins in cultured Caco-2 cell monolayers. PB biotransformed P-PAC into bioavailable metabolites and potentially reduced the toxicity of P-PAC. The toxicity of P-PAC and their synbiotics need to be critically evaluated for the safety of human consumption.

Indian National Association for Study of the Liver (INASL) Guidance Paper on Nomenclature, Diagnosis and Treatment of Nonalcoholic Fatty Liver Disease (NAFLD)

Nonalcoholic fatty liver disease (NAFLD) is a major cause of chronic liver disease globally and in India. The already high burden of NAFLD in India is expected to further increase in the future in parallel with the ongoing epidemics of obesity and type 2 diabetes mellitus. Given the high prevalence of NAFLD in the community, it is crucial to identify those at risk of progressive liver disease to streamline referral and guide proper management. Existing guidelines on NAFLD by various international societies fail to capture the entire landscape of NAFLD in India and are often difficult to incorporate in clinical practice due to fundamental differences in sociocultural aspects and health infrastructure available in India. A lot of progress has been made in the field of NAFLD in the 7 years since the initial position paper by the Indian National Association for the Study of Liver on NAFLD in 2015. Further, the ongoing debate on the nomenclature of NAFLD is creating undue confusion among clinical practitioners. The ensuing comprehensive review provides consensus-based, guidance statements on the nomenclature, diagnosis, and treatment of NAFLD that are practically implementable in the Indian setting.

Characterization of signature trends across the spectrum of non-alcoholic fatty liver disease using deep learning method

AIMS

The timely diagnosis of different stages in NAFLD is crucial for disease treatment and reversal. We used hepatocellular ballooning to determine different NAFLD stages.

MAIN METHODS

We analyzed differentially expressed genes (DEGs) in 78 patients with NAFLD and in healthy controls from previously published RNA-seq data. We identified two expression types in NAFLD progression, calculated the predictive power of candidate genes, and validated them in an independent cohort. We also performed cancer studies with these candidates retrieved from the Cancer Genome Atlas.

KEY FINDINGS

We identified 103 DEGs in NAFLD patients compared to healthy controls: 75 genes gradually increased or decreased in the NAFLD stage, whereas 28 genes showed differences only in NASH. The former were enriched in negative regulation and binding-related genes; the latter were involved in positive regulation and cell proliferation. Feature selection showed the gradual up- or down-regulation of 21 genes in NASH compared to controls; 18 were highly expressed only in NASH. Using deep-learning method with subset of features from lasso regression, we obtained reliable determination performance in NAFL and NASH (accuracy: 0.857) and validated these genes using an independent cohort (accuracy: 0.805). From cancer studies, we identified significant differential expression of several candidate genes in LIHC; 5 genes were gradually up-regulated and 6 showing high expression only in NASH were influential to patient survival.

SIGNIFICANCE

The identified biomolecular signatures may determine the spectrum of NAFLD and its relationship with HCC, improving clinical diagnosis and prognosis and enabling a therapeutic intervention for NAFLD.

Loss of hepatic phosphoenolpyruvate carboxykinase 1 dysregulates metabolic responses to acute exercise but enhances adaptations to exercise training in mice

Acute exercise increases liver gluconeogenesis to supply glucose to working muscles. Concurrently, elevated liver lipid breakdown fuels the high energetic cost of gluconeogenesis. This functional coupling between liver gluconeogenesis and lipid oxidation has been proposed to underlie the ability of regular exercise to enhance liver mitochondrial oxidative metabolism and decrease liver steatosis in individuals with nonalcoholic fatty liver disease. Herein we tested whether repeated bouts of increased hepatic gluconeogenesis are necessary for exercise training to lower liver lipids. Experiments used diet-induced obese mice lacking hepatic phosphoenolpyruvate carboxykinase 1 (KO) to inhibit gluconeogenesis and wild-type (WT) littermates. 2H/13C metabolic flux analysis quantified glucose and mitochondrial oxidative fluxes in untrained mice at rest and during acute exercise. Circulating and tissue metabolite levels were determined during sedentary conditions, acute exercise, and refeeding postexercise. Mice also underwent 6 wk of treadmill running protocols to define hepatic and extrahepatic adaptations to exercise training. Untrained KO mice were unable to maintain euglycemia during acute exercise resulting from an inability to increase gluconeogenesis. Liver triacylglycerides were elevated after acute exercise and circulating β-hydroxybutyrate was higher during postexercise refeeding in untrained KO mice. In contrast, exercise training prevented liver triacylglyceride accumulation in KO mice. This was accompanied by pronounced increases in indices of skeletal muscle mitochondrial oxidative metabolism in KO mice. Together, these results show that hepatic gluconeogenesis is dispensable for exercise training to reduce liver lipids. This may be due to responses in ketone body metabolism and/or metabolic adaptations in skeletal muscle to exercise.NEW & NOTEWORTHY Exercise training reduces hepatic steatosis partly through enhanced hepatic terminal oxidation. During acute exercise, hepatic gluconeogenesis is elevated to match the heightened rate of muscle glucose uptake and maintain glucose homeostasis. It has been postulated that the hepatic energetic stress induced by elevating gluconeogenesis during acute exercise is a key stimulus underlying the beneficial metabolic responses to exercise training. This study shows that hepatic gluconeogenesis is not necessary for exercise training to lower liver lipids.

Non-alcoholic fatty liver disease-A pilot study investigating early inflammatory and fibrotic biomarkers of NAFLD with alcoholic liver disease

Introduction: Non-alcoholic fatty liver disease (NAFLD) is a condition where excess fat accumulates in the liver (hepatic steatosis) and there is no history of alcohol abuse or other secondary causes of chronic liver disease. NAFLD is a very common disorder, occurring in 25% of the global population. NAFLD is now the most common chronic liver disorder in Western countries. Liver biopsy is the gold standard for NAFLD diagnosis and staging; however, this is invasive, costly and not without risk. Biomarkers that could diagnose and stage disease would reduce the need for biopsy and allow stratification of patients at risk of progression to non-alcoholic steatohepatitis (NASH). Methods: One hundred and thirty-five patients were involved in the study [N = 135: n = 34 controls; n = 26 simple steatosis; n = 61 NAFLD/NASH, and n = 14 alcoholic liver disease (ALD)]. Clinically diagnosed (ICD-10) patient serum samples were obtained from Discovery Life Sciences (US) along with clinical history. Samples were run in duplicate using high-sensitivity cytokine array I, immunoassays and ELISAs. In total, n = 20 individual biomarkers were investigated in this pilot study. Results: Thirteen/20 (65%) biomarkers were identified as significantly different between groups; IFNγ, EGF, IL-1β, IL-6, IL-8, IL-10, TNFα, FABP-1, PIIINP, ST2/IL-33R, albumin, AST and ALT. Five/20 (25%) biomarker candidates were identified for further investigation; namely, three biomarkers of inflammation, IL-6, IL-8, and TNFα, and two biomarkers of fibrosis, PIIINP and ST2/IL-33R. Discussion: Single biomarkers are unlikely to be diagnostic or predictive at staging NAFLD due to the complex heterogeneity of the disease. However, biomarker combinations may help stratify risk and stage disease where patients are averse to biopsy. Further studies comparing the 5 biomarkers identified in this study with current diagnostic tests and fibrotic deposition in liver tissue are warranted.

Coffee modulates insulin-hepatocyte nuclear factor-4α-Cyp7b1 pathway and reduces oxysterol-driven liver toxicity in a nonalcoholic fatty liver disease mouse model

Oxysterol 7α-hydroxylase (CYP7B1) controls the levels of intracellular regulatory oxysterols generated by the "acidic pathway" of cholesterol metabolism. Previously, we demonstrated that an inability to upregulate CYP7B1 in the setting of insulin resistance leads to the accumulation of cholesterol metabolites such as (25R)26-hydroxycholesterol (26HC) that initiate and promote hepatocyte injury; followed by an inflammatory response. The current study demonstrates that dietary coffee improves insulin resistance and restores Cyp7b1 levels in a well-characterized Western diet (WD)-induced nonalcoholic fatty liver disease (NAFLD) mouse model. Ingestion of a WD containing caffeinated (regular) coffee or decaffeinated coffee markedly reduced the serum ALT level and improved insulin resistance. Cyp7b1 mRNA and protein levels were preserved at normal levels in mice fed the coffee containing WD. Additionally, coffee led to upregulated steroid sulfotransferase 2b1 (Sult2b1) mRNA expression. In accordance with the response in these oxysterol metabolic genes, hepatocellular 26HC levels were maintained at physiologically low levels. Moreover, the current study provided evidence that hepatic Cyp7b1 and Sult2b1 responses to insulin signaling can be mediated through a transcriptional factor, hepatocyte nuclear factor (HNF)-4α. We conclude coffee achieves its beneficial effects through the modulation of insulin resistance. Both decaffeinated and caffeinated coffee had beneficial effects, demonstrating caffeine is not fundamental to this effect. The effects of coffee feeding on the insulin-HNF4α-Cyp7b1 signaling pathway, whose dysregulation initiates and contributes to the onset and progression of NASH as triggered by insulin resistance, offer mechanistic insight into approaches for the treatment of NAFLD.NEW & NOTEWORTHY This study demonstrated dietary coffee prevented the accumulation of hepatic oxysterols by maintaining Cyp7b1/Sult2b1 expression in a diet-induced NAFLD mice model. Lowering liver oxysterols markedly reduced inflammation in the coffee-ingested mice. Caffeine is not fundamental to this effect. In addition, this study showed Cyp7b1/Sult2b1 responses to insulin signaling can be mediated through a transcriptional factor, HNF4α. The insulin-HNF4α-Cyp7b1/Sult2b1 signaling pathway, which directly correlates to the onset of NASH triggered by insulin resistance, offers insight into approaches for NAFLD treatment.

Machine learning to predict progression of non-alcoholic fatty liver to non-alcoholic steatohepatitis or fibrosis

Background

Non-alcoholic fatty liver (NAFL) can progress to the severe subtype non-alcoholic steatohepatitis (NASH) and/or fibrosis, which are associated with increased morbidity, mortality, and healthcare costs. Current machine learning studies detect NASH; however, this study is unique in predicting the progression of NAFL patients to NASH or fibrosis.

Aim

To utilize clinical information from NAFL-diagnosed patients to predict the likelihood of progression to NASH or fibrosis.

Methods

Data were collected from electronic health records of patients receiving a first-time NAFL diagnosis. A gradient boosted machine learning algorithm (XGBoost) as well as logistic regression (LR) and multi-layer perceptron (MLP) models were developed. A five-fold cross-validation grid search was utilized for hyperparameter optimization of variables, including maximum tree depth, learning rate, and number of estimators. Predictions of patients likely to progress to NASH or fibrosis within 4 years of initial NAFL diagnosis were made using demographic features, vital signs, and laboratory measurements.

Results

The XGBoost algorithm achieved area under the receiver operating characteristic (AUROC) values of 0.79 for prediction of progression to NASH and 0.87 for fibrosis on both hold-out and external validation test sets. The XGBoost algorithm outperformed the LR and MLP models for both NASH and fibrosis prediction on all metrics.

Conclusion

It is possible to accurately identify newly diagnosed NAFL patients at high risk of progression to NASH or fibrosis. Early identification of these patients may allow for increased clinical monitoring, more aggressive preventative measures to slow the progression of NAFL and fibrosis, and efficient clinical trial enrollment.

FibroScan-AST (FAST) Score for Nonalcoholic Steatohepatitis - Validation in an Indian Cohort

Background

The FibroScan-AST (FAST) score was recently described to detect patients with nonalcoholic steatohepatitis (NASH) having elevated nonalcoholic fatty liver disease (NAFLD) activity score (NAS ≥ 4) and significant fibrosis (≥ F2) on liver biopsy (NASH+ NAS ≥ 4 + F ≥ 2).

Aim

The aim of this study was to validate the FAST score in Indian patients with NAFLD and to derive optimal cut-offs.

Methods

Sixty patients with biopsy-proven NAFLD [men: 38 (63.3%), age 40 (32-52) years] with all parameters for assessing the FAST score within 3 months of liver histology were retrospectively analysed.

Results

Histological NASH was present in 17 patients (28.3%), while 11 (18.3%) patients had NASH + NAS ≥ 4 + F ≥ 2. The area under the curve (AUROC) of the FAST score for discriminating NASH + NAS ≥ 4 + F ≥ 2 was 0.81. Using cut-offs by Newsome et al, the rule-out cut-off (FAST: ≤ 0.35) had a negative predictive value (NPV) of 0.88 [sensitivity: 0.91, specificity: 0.14, negative likelihood ratio (LR): 0.64], while the rule-in cut-off (FAST: ≥ 0.67) had a positive predictive value (PPV) of 0.33 (sensitivity: 0.73, specificity: 0.67, positive LR: 2.22). Fifteen (25%) patients were correctly classified as per histology, while 28 (46.67%) patients fell in the grey zone. On recalculating the optimal cut-offs for our patients, the rule-out cut-off (FAST: ≤ 0.55) had an NPV of 0.95 (sensitivity: 0.90, specificity: 0.45, negative LR: 0.21), while the optimal rule-in cut-off (FAST: ≥ 0.78) had a PPV of 0.70 (sensitivity: 0.64, specificity 0.94, positive LR: 10.39). With these cut-offs, 27 (45%) patients fell in the grey zone and 29 (48.3%) were correctly classified as per histology, performing better than the cut-offs by Newsome et al (P < 0.001).

Conclusion

The FAST score demonstrates good AUROC for detecting NASH with significant fibrosis and inflammation on histology. Cut-offs should be recalibrated based on prevalence of disease.

Lay summary

India has a high burden of NAFLD with an estimated 25 million patients at potential risk for significant liver disease. Liver biopsy remains the gold standard for diagnosing NASH, although its application in routine clinical practice is limited. Noninvasive tests for the simultaneous detection of steatosis, inflammation and fibrosis are thus the need of the hour. The FAST score has been recently suggested for the noninvasive detection of NASH with significant fibrosis (≥ F2) and inflammation (NAS ≥ 4) on liver biopsy. We validated the utility of the FAST score for detecting NASH with significant fibrosis and inflammation on liver biopsy in Indian patients with NAFLD. This noninvasive, easy-to-use and nonproprietary FAST score can correctly classify disease severity in more than 50% patients. However, our results suggest that cut-offs should be recalibrated based on the anticipated prevalence of NASH + NAS ≥ 4 + F ≥ 2 in the given population.

Low Screening Rates Despite a High Prevalence of Significant Liver Fibrosis in People with Diabetes from Primary and Secondary Care

Diabetes is a driver of non-alcoholic fatty liver disease (NAFLD) and fibrosis. We determine current practices in examining liver fibrosis in people with diabetes and record prevalence levels in primary and secondary care. We extracted HbA_1c results ≥48 mmol/mol to identify people with diabetes, then examined the proportion who had AST, ALT, and platelets results, facilitating calculation of non-invasive fibrosis tests (NIT), or an enhanced liver fibrosis score. Fibrosis markers were requested in only 1.49% (390/26,090), of which 29.7% (n = 106) had evidence of significant fibrosis via NIT. All patients at risk of fibrosis had undergone transient elastography (TE), biopsy or imaging. TE and biopsy data showed that 80.6% of people with raised fibrosis markers had confirmed significant fibrosis. We also show that fibrosis levels as detected by NIT are marginally lower in patients treated with newer glucose lowering agents (sodium-glucose transporter protein 2 inhibitors, dipeptidyl peptidase-4 inhibitors and glucagon-like peptide-1 receptor agonists). In conclusion by utilising a large consecutively recruited dataset we demonstrate that liver fibrosis is infrequently screened for in patients with diabetes despite high prevalence rates of advanced fibrosis. This highlights the need for cost-effectiveness analyses to support the incorporation of widespread screening into national guidelines and the requirement for healthcare practitioners to incorporate NAFLD screening into routine diabetes care.

Heterogeneity of non-alcoholic fatty liver disease: Implications for clinical practice and research activity

Non-alcoholic fatty liver disease (NAFLD) is a heterogeneous condition with a wide spectrum of clinical presentations and natural history and disease severity. There is also substantial inter-individual variation and variable response to a different therapy. This heterogeneity of NAFLD is in turn influenced by various factors primarily demographic/dietary factors, metabolic status, gut microbiome, genetic predisposition together with epigenetic factors. The differential impact of these factors over a variable period of time influences the clinical phenotype and natural history. Failure to address heterogeneity partly explains the sub-optimal response to current and emerging therapies for fatty liver disease. Consequently, leading experts across the globe have recently suggested a change in nomenclature of NAFLD to metabolic-associated fatty liver disease (MAFLD) which can better reflect current knowledge of heterogeneity and does not exclude concomitant factors for fatty liver disease (e.g. alcohol, viral hepatitis, etc.). Precise identification of disease phenotypes is likely to facilitate clinical trial recruitment and expedite translational research for the development of novel and effective therapies for NAFLD/MAFLD.

Current and Emerging Biomarkers and Imaging Modalities for Nonalcoholic Fatty Liver Disease: Clinical and Research Applications

PURPOSE

Nonalcoholic fatty liver disease (NAFLD) is a metabolic disorder that frequently coexists with obesity, metabolic syndrome, and type 2 diabetes. The NAFLD spectrum, ranging from hepatic steatosis to nonalcoholic steatohepatitis, fibrosis, and cirrhosis, can be associated with long-term hepatic (hepatic decompensation and hepatocellular carcinoma) and extrahepatic complications. Diagnosis of NAFLD requires detection of liver steatosis with exclusion of other causes of chronic liver disease. Screening for NAFLD and identification of individuals at risk of end-stage liver disease represent substantial challenges that have yet to be met. NAFLD affects up to 25% of adults, yet only a small proportion will progress beyond steatosis to develop advanced disease (steatohepatitis and fibrosis) associated with increased morbidity and mortality. Identification of this cohort has required the gold standard liver biopsy, which is both invasive and expensive. The use of serum biomarkers and noninvasive imaging techniques is an area of significant clinical relevance. This narrative review outlines current and emerging technologies for the diagnosis of NAFLD, nonalcoholic steatohepatitis, and hepatic fibrosis.

METHODS

We reviewed the literature using PubMed and reviewed national and international guidelines and conference proceedings to provide a comprehensive overview of the evidence.

FINDINGS

Significant advances have been made during the past 2 decades that have enhanced noninvasive assessment of NAFLD without the need for liver biopsy. For the detection of steatosis, abdominal ultrasonography remains the first-line investigation, although a controlled attenuation parameter using transient elastography is more sensitive. For detecting fibrosis, noninvasive serum markers of fibrosis and algorithms based on routine biochemistry are available, in addition to transient elastography. These techniques are well validated and have been incorporated into national and international screening guidelines. These approaches have facilitated more judicious use of liver biopsy but are yet to entirely replace it. Although serum biomarkers present a pragmatic and widely available screening approach for NAFLD in large population-based studies, magnetic resonance imaging techniques offer the benefit of achieving high degrees of accuracy in disease grading, tumor staging, and assessing therapeutic response.

IMPLICATIONS

This diagnostic clinical and research field is rapidly evolving; increasingly combined applications of biomarkers and transient elastography or imaging of selective (intermediate or high risk) cases are being used for clinical and research purposes. Liver biopsy remains the gold standard investigation, particularly in the context of clinical trials, but noninvasive options are emerging, using multimodality assessment, that are quicker, more tolerable, more widely available and have greater patient acceptability.

Subclinical atherosclerosis and arterial stiffness in nonalcoholic fatty liver disease: A case-control study in Algerian population

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) was described for the first time in 1980, and became within a few years one of the most frequent causes of chronic liver disease. However, during the last decade, many studies suggested a strong relationship between NAFLD and cardiovascular diseases including carotid atherosclerosis evoking the hypothesis that NAFLD is a factor or a marker of cardiovascular risk. In Algeria, data on this subject are rare or inexistent. The objective of our work was to study the relationship between NAFLD and atherosclerosis in an Algerian population without diabetes.

PATIENTS AND METHODS

It is a case-control study with a strict matching by age and sex. Non-diabetic participants between 30 and 70 years of age were consecutively included in the department of internal medicine of the public hospital of El Biar. The diagnosis of NAFLD was made by ultrasound and hepatic elasticity was assessed by FibroScan®. We collected the data of the carotid ultrasound, the carotid-femoral pulse wave velocity (cfPWV), ankle-brachial pressure index and arterial pressure (consultation and ambulatory monitoring). Non parametric statistical methods (chi 2 McNemar for the percentages, t Friedman test for medium) were used and the association between variables was estimated by odds ratio (OR). These analyses were performed using SPSS 21.0 software (IBM).

RESULTS

213 patients with NAFLD, with a mean age of 48.5 years±10.14 (100 men/113 women) were matched to 213 controls. The presence of carotid atherosclerotic plaque (CAP) was higher in NAFLD than in controls (31.92% (n=68) vs. 7.05% (n=15), P<0.001). In multivariate analysis, the CAP (OR 8.6, 95% CI [3.6-20.5], P<0.001), high Intima media thickness (OR 2.8, 95% CI [1.4-5.4], P=0.002), CRP≥6mg/l (OR 14.7, 95% CI [5.9-36.9], P=0.001), abdominal obesity (OR 3.8, 95% CI [1.4-9.7], P=0.05), high cfPWV (OR 4.4, 95% CI [2.4-8.1], P<0.001), elevated alanine aminotransferase(OR 4.0, 95% CI [1.6-9.8], P=0.002), overall obesity (OR 2.0, 95% CI [1.0-3.8], P=0.03), dyslipidemia (OR 2.0, 95% CI [1.0-3.8], P=0.02), and elevated GGT (OR 2.8, 95% [1.1-7.1] were independently associated to NAFLD.

CONCLUSION

Our study suggests that NAFLD is significantly associated with carotid atherosclerosis and arterial stiffness. These results may have implications in the management of patients with NAFLD in terms of cardiovascular prevention.

The risk of hepatic adverse events of systemic medications for psoriasis: a prospective cohort study using the BIOBADADERM registry

BACKGROUND

Limited information is available regarding the risk of incident liver disease in patients with psoriasis receiving systemic therapies.

OBJECTIVES

To describe the liver safety findings of conventional and modern systemic therapies for moderate-to-severe psoriasis, and to compare the relative incidence rates of hepatic adverse events (AEs) for each drug.

METHODS

All the patients on the BIOBADADERM registry were included. Crude and adjusted incidence rate ratios (cIRR and aIRR, respectively) of hepatic AEs, using anti-TNF drugs as reference, were determined. Outcomes of interest were hypertransaminasemia, nonalcoholic fatty liver disease (NADFLD) and a group of other, less represented, hepatic AEs.

RESULTS

Our study included 3,171 patients exposed to systemic drugs (6279 treatment cycles). Incident hypertransaminasemia was the most frequent hepatic AE (incidence rate of 21 per 1000 patients-years [CI 95% CI 18-23]), followed by NAFLD (8 cases per 1000 patients-years [95% CI 6-10]). Methotrexate (aIRR 3.06 [2.31-4.4]; p = 0.000) and cyclosporine (aIRR 2.37 [1.05-5.35]; p = 0.0378) were associated with an increased risk for hypertransaminasemia when compared to anti-TNF-α agents. No differences were observed between different groups of biologics. Conventional therapies were not associated with new incident NAFLD.

CONCLUSIONS

Comparative information of the incidence of hepatic AEs could facilitate drug selection in moderate-to-severe psoriasis.

Diagnostic management of nonalcoholic fatty liver disease: a transformational period in the development of diagnostic and predictive tools-a narrative review

NAFLD is an emerging healthcare epidemic that is causing predictable adverse consequences for healthcare systems, societies and individuals. Whilst NAFLD is recognized as a multi-system disease with compound pathways that are both benign and pernicious in their unfolding; NASH is generally understood as a deleterious follow-on condition with path-specific tendencies that progress to cirrhosis, HCC and liver transplantation. Recent evidence is beginning to challenge this interpretation demanding more attention to the personalized nature of the disease and its pathogenesis across multiple different cohorts. This means that we need better diagnostic and prognostic tools not only to capture those 'at risk' disease phenotypes; but for better stratification and monitoring of patients according to their treatment strategies. With the advent of pipeline therapies for NASH underway, the medical profession looks to adopt more accurate non-invasive diagnostic tools that can help to delineate and eliminate NASH histology. This review looks at the search for the killer application revealing this particular moment in time as a transformational period; one that is pushing the boundaries of technology to integrate diverse panels of species through sensitive profiling and multi-omics approaches that cast wide, yet powerful diagnostic nets that have the potential to elucidate pathway specific biomarkers that are personalized and predictable.

A Scoping Review on Lipocalin-2 and Its Role in Non-Alcoholic Steatohepatitis and Hepatocellular Carcinoma

Excess calorie intake and a sedentary lifestyle have made non-alcoholic fatty liver disease (NAFLD) one of the fastest growing forms of liver disease of the modern world. It is characterized by abnormal accumulation of fat in the liver and can range from simple steatosis and non-alcoholic steatohepatitis (NASH) to cirrhosis as well as development of hepatocellular carcinoma (HCC). Biopsy is the golden standard for the diagnosis and differentiation of all NAFLD stages, but its invasiveness poses a risk for patients, which is why new, non-invasive ways of diagnostics ought to be discovered. Lipocalin-2 (LCN2), which is a part of the lipocalin transport protein family, is a protein formally known for its role in iron transport and in inflammatory response. However, in recent years, its implication in the pathogenesis of NAFLD has become apparent. LCN2 shows significant upregulation in several benign and malignant liver diseases, making it a good candidate for the NAFLD biomarker or even a therapeutic target. What makes LCN2 more interesting to study is the fact that it is overexpressed in HCC development induced by chronic NASH, which is one of the primary causes of cancer-related deaths. However, to this day, neither its role as a biomarker for NAFLD nor the molecular mechanisms of its implication in NAFLD pathogenesis have been completely elucidated. This review aims to gather and closely dissect the current knowledge about, sometimes conflicting, evidence on LCN2 as a biomarker for NAFLD, its involvement in NAFLD, and NAFLD-HCC related pathogenesis, while comparing it to the findings in similar pathologies.

[The harmfulness of simple steatosis]

Over the past decades, non-alcoholic fatty liver disease (NAFLD) has emerged as the leading cause of chronic liver diseases in western societies. While the complications of NAFLD progression and particularly non-alcoholic steatohepatitis (NASH) have been widely recognized and statistically proven by emerging numbers of NASH related cirrhosis, transplantations and liver cancer, simple steatosis was widely recognized as a rather benign manifestation of NAFLD. However, emerging data suggests simple steatosis to be associated with increased mortality, related to hepatic- and extrahepatic manifestations of multiple metabolic and inflammatory complications of the disease. This brief review focusses on novel aspects related to the pathogenesis and clinical relevance of simple steatosis. Based on these findings, we recommend a thorough interdisciplinary approach to patients with simple steatosis by dedicated specialized centers. The rising prevalence demands the implementation and evaluation of non-invasive screening methods and multidisciplinary preventive approaches, as according to current data, we face an epidemic of hepatic steatosis in over 25 % of the population.

Insulin resistance dysregulates CYP7B1 leading to oxysterol accumulation: a pathway for NAFL to NASH transition

NAFLD is an important public health issue closely associated with the pervasive epidemics of diabetes and obesity. Yet, despite NAFLD being among the most common of chronic liver diseases, the biological factors responsible for its transition from benign nonalcoholic fatty liver (NAFL) to NASH remain unclear. This lack of knowledge leads to a decreased ability to find relevant animal models, predict disease progression, or develop clinical treatments. In the current study, we used multiple mouse models of NAFLD, human correlation data, and selective gene overexpression of steroidogenic acute regulatory protein (StarD1) in mice to elucidate a plausible mechanistic pathway for promoting the transition from NAFL to NASH. We show that oxysterol 7α-hydroxylase (CYP7B1) controls the levels of intracellular regulatory oxysterols generated by the "acidic/alternative" pathway of cholesterol metabolism. Specifically, we report data showing that an inability to upregulate CYP7B1, in the setting of insulin resistance, results in the accumulation of toxic intracellular cholesterol metabolites that promote inflammation and hepatocyte injury. This metabolic pathway, initiated and exacerbated by insulin resistance, offers insight into approaches for the treatment of NAFLD.

Pro-Resolving Lipid Mediator Resolvin E1 Mitigates the Progress of Diethylnitrosamine-Induced Liver Fibrosis in Sprague-Dawley Rats by Attenuating Fibrogenesis and Restricting Proliferation

Liver fibrosis is a complex process associated to most types of chronic liver disease, which is characterized by a disturbance of hepatic tissue architecture and the excessive accumulation of extracellular matrix. Resolvin E1 (RvE1) is a representative member of the eicosapentaenoic omega-3 lipid derivatives, and is a drug candidate of the growing family of endogenous resolvins. Considering the aforementioned, the main objective of this study was to analyze the hepatoprotective effect of RvE1 in a rat model of liver fibrosis. Male Sprague-Dawley rats received diethylnitrosamine (DEN, 70 mg/mg body weight intraperitoneally (i.p)) as an inductor of liver fibrosis once weekly and RvE1(100 ng/body weight i.p) twice weekly for four weeks. RvE1 suppressed the alterations induced by DEN, normalizing the levels of alanine aminotransferase (ALT), albumin, and lactate dehydrogenase (LDH), and ameliorated DEN injury by decreasing the architecture distortion, inflammatory infiltration, necrotic areas, and microsteatosis. RvE1 also limited DEN-induced proliferation through a decrease in Ki67-positive cells and cyclin D1 protein expression, which is related to an increase of the levels of cleaved caspase-3. Interestingly, we found that RvE1 promotes higher nuclear translocation of nuclear factor κB (NF-κB)p65 than DEN. RvE1 also increased the levels of nuclear the nuclear factor erythroid 2-related factor 2 (Nrf2), but with no antioxidant effect, measured as an increase in glutathione disulfide (GSSG) and a decrease in the ratio of glutathione (GSH)/GSSG. Taken together, these results suggest that RvE1 modulates the fibrogenesis, steatosis, and cell proliferation in a model of DEN induced fibrosis.

ERAS Protocol for Perioperative Care of Patients Treated with Laparoscopic Nonanatomic Liver Resection for Hepatocellular Carcinoma: The ISMETT Experience

Background: Liver resection (LR) remains the best therapeutic option for patients with early-stage hepatocellular carcinoma (HCC) with preserved hepatic function and who are not eligible for liver transplantation. After its inception, the enhanced recovery after surgery (ERAS) protocol was widely used for treating patients with liver cancer, although there are still no clear indications for improving upon it in both open and laparoscopic surgery. Objective: This study aims to describe our institute's experience in the application of the ERAS protocol in a cohort of HCC patients, and to explore possible factors that could have an impact on postoperative outcomes. Materials and Methods: We retrospectively analyzed our experience with LR performed from September 2017 to January 2020 in patients treated with ERAS protocol, focusing on describing impact on postoperative nutrition, analgesic requirements, and length of hospitalization. Demographics, operative factors, and postoperative complications of patients were reviewed. Results: During the study period, 89 HCC patients were eligible for LR, and 75% of patients presented with liver cirrhosis. The most prevalent among etiologic factors was hepatitis C virus infection (53 patients out of 89, 60%), followed by nonalcoholic steatohepatitis (18 patients, 20%). The median age was 70 years. Liver cirrhosis did not have an impact on postoperative course of patients. Patients who underwent laparoscopic surgery and nonanatomic LR experienced low complication rates, shorter length of stay, and shorter time of intravenous analgesic requirements. Conclusions: Continual refinement with ERAS protocol for treating HCC patients based on perioperative counseling and surgical decision-making is crucial to guarantee low complication rates, and reduce patient morbidity and time for recovery.