Prevalence, gender, ethnic variations, and prognosis of NASH

Machine Learning-Based Non-Invasive Prediction of Metabolic Dysfunction-Associated Steatohepatitis in Obese Patients: A Retrospective Study

Objectives: We aimed to develop and validate machine learning (ML) models that integrate clinical and laboratory data for the non-invasive prediction of metabolic dysfunction-associated steatohepatitis (MASH) in an obese population. Methods: In this retrospective study, clinical and laboratory data were collected from obese patients undergoing bariatric surgery. The cohort was divided using stratified random sampling, and optimal features were selected with SHapley Additive exPlanations (SHAP). Various ML models, including K-nearest neighbors, linear support vector machine, radial basis function support vector machine, Gaussian process, random forest, multilayer perceptron, adaptive boosting, and naïve Bayes, were developed through cross-validation and hyperparameter tuning. Diagnostic performance was assessed via the area under the curve (AUC) in both training and validation sets. Results: A total of 558 patients were analyzed, with 390 in the training set and 168 in the validation set. In the training cohort, the median age was 35 years, the median body mass index (BMI) was 39.8 kg/m2, 39.0% were male, 37.9% had diabetes mellitus, and 62.8% were diagnosed with MASH. The validation cohort had a median age of 34.1 years, a median BMI of 42.5 kg/m2, 41.7% male, 32.7% with diabetes, and 39.9% with MASH. Among the models, the random forest achieved the highest performance among the models with AUC values of 0.94 in the training set and 0.88 in the validation set. The Gaussian process model attained an AUC of 0.97 in the training cohort but 0.79 in the validation cohort, while the other models achieved AUC values ranging from 0.63 to 0.88 in the training cohort and 0.62 to 0.75 in the validation set. Conclusions: ML models, particularly the random forest, effectively predict MASH using readily available data, offering a promising non-invasive alternative to conventional serological scoring. Prospective studies and external validations are needed to further establish clinical utility.

Causal Relationships between Iron Status and Nonalcoholic Fatty Liver Disease: Two-Sample, Multivariable, and Two-Step Mendelian Randomization

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) was clinically documented to be accompanied by iron homeostasis imbalances, however, the causal relationship between them remains unclear. Therefore, this study aimed to examine the relationship between iron homeostasis indicators (serum iron, ferritin, transferrin, total iron binding capacity (TIBC), and transferrin saturation (TSAT)) and NAFLD risk.

METHODS

We applied two-sample Mendelian randomization (MR) to assess the effects of genetic liability to iron homeostasis indicators (N = 43,220-246,139) on NAFLD risk (N = 377,988) in individuals of European ancestry. Reverse direction MR, multivariable MR, and two-step MR were performed to estimate reverse association, causal effects independent of smoking or drinking, and the mediating effect of lipid metabolism, respectively. Smoking and drinking as confounders were considered confounders.

RESULTS

Genetically predicted serum iron, ferritin, and TSAT were significantly associated with a higher risk of NAFLD (odds ratio (OR): 1.286, 95% confidence interval (CI): 1.075-1.539; p = 0.0059; OR: 1.260, 95% CI: 1.050-1.500, p = 0.0195; and OR: 1.223, 95% CI: 1.067-1.402; p = 0.0039, respectively). Reverse direction MR analysis suggested that genetic liability to NAFLD had no significant causal effect on iron homeostasis. Sex-specific MR exhibited a stronger effect size for the association of elevated ferritin with NAFLD risk in males (OR: 1.723, 95% CI: 1.338-2.219; p = 2.48 × 10-5). Two-step MR revealed that elevated triglycerides (TGs) mediated approximately 3%-5% of the observed effect of serum iron and TSAT on NAFLD risk, while decreased low-density lipoprotein cholesterol (LDL-C) mediated 9%-10%.

CONCLUSION

Genetic liability to iron status imbalance may causally affect NAFLD. This evidence may support the clinical treatment of NAFLD in the target population.

Hepatic HKDC1 deletion alleviates western diet-induced MASH in mice

The global prevalence of Metabolic Dysfunction-Associated Steatohepatitis (MASH) has been rising sharply, closely mirroring the increasing rates of obesity and metabolic syndrome. MASH exhibits a strong sexual dimorphism where females are affected with more severe forms after menopause. Hexokinase domain-containing protein 1 (HKDC1) has recently been recognized for its role in liver diseases, where its expression is minimal under normal conditions but significantly increases in response to metabolic stressors like obesity and liver injury. This selective upregulation suggests HKDC1's potential specialization in hepatic glucose and lipid dysregulation, linking it closely to the progression of MASH. This study aims to clarify the role of HKDC1 in Western diet-induced MASH in female mice by examining its impact on hepatic glucose and lipid metabolism, offering insights into its potential as a therapeutic target and addressing the need for sex-specific research in liver disease. This study reveals that HKDC1 expression is elevated in obese women with MASH and correlates with liver pathology. In a mouse model, liver-specific HKDC1 knockout (HKDC1LKO) protected against Western diet-induced obesity, glucose intolerance, and MASH features, including steatosis, inflammation, and fibrosis. Transcriptomic analysis showed that HKDC1 deletion reduced pro-inflammatory and pro-fibrotic gene expression, while gut microbiome analysis indicated a shift toward MASH-protective bacteria. These findings suggest that HKDC1 may exacerbate MASH progression through its role in metabolic and inflammatory pathways, making it a potential therapeutic target.

Sex differences in predicting dyslipidemia using polygenic risk score with fatty liver index and fibrotic nonalcoholic steatohepatitis index

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are recognized risk factors for dyslipidemia. Current prediction models that rely solely on dyslipidemia polygenic risk score (PRS) have certain limitations. We aimed to validate simple indexes for NAFLD and NASH as predictors of dyslipidemia using the PRS. This study utilized cohort data from an urban population-based dataset comprising 48,263 South Koreans. The incidence of dyslipidemia was higher in men than in women (32.4% and 27.8%; p < 0.001). The PRS model predicted dyslipidemia more accurately in men (AUROC [95% confidence intervals]: 0.645 [0.636-0.754]). Notably, integrating the fatty liver index (FLI) and fibrotic NASH index (FNI) with the PRS model resulted in the highest accuracy in diagnosing dyslipidemia, particularly in men (AUROC [95% confidence intervals]: 0.704 [0.698-0.711]). In conclusion, a predictive model combining the PRS with FLI and FNI was validated. This model offers more accurate predictive value for diagnosing dyslipidemia, particularly in East Asian men. Thus, our study has the clinical potential for identifying high-risk individuals and determining preventive measures for dyslipidemia in a sex-specific manner.

Integrative transcriptomic and genomic analyses unveil the IFI16 variants and expression as MASLD progression markers

BACKGROUND AND AIMS

Metabolic dysfunction-associated steatotic liver disease (MASLD) encompasses a broad and continuous spectrum of liver diseases ranging from fatty liver to steatohepatitis. The intricate interactions of genetic, epigenetic, and environmental factors in the development and progression of MASLD remain elusive. Here, we aimed to achieve an integrative understanding of the genomic and transcriptomic alterations throughout the progression of MASLD.

APPROACH AND RESULTS

RNA-Seq profiling (n = 146) and whole-exome sequencing (n = 132) of MASLD liver tissue samples identified 3 transcriptomic subtypes (G1-G3) of MASLD, which were characterized by stepwise pathological and molecular progression of the disease. Macrophage-driven inflammatory activities were identified as a key feature for differentiating these subtypes. This subtype-discriminating macrophage interplay was significantly associated with both the expression and genetic variation of the dsDNA sensor IFI16 (rs6940, A>T, T779S), establishing it as a fundamental molecular factor in MASLD progression. The in vitro dsDNA-IFI16 binding experiments and structural modeling revealed that the IFI16 variant exhibited increased stability and stronger dsDNA binding affinity compared to the wild-type. Further downstream investigation suggested that the IFI16 variant exacerbated DNA sensing-mediated inflammatory signals through mitochondrial dysfunction-related signaling of the IFI16-PYCARD-CASP1 pathway.

CONCLUSIONS

This study unveils a comprehensive understanding of MASLD progression through transcriptomic classification, highlighting the crucial roles of IFI16 variants. Targeting the IFI16-PYCARD-CASP1 pathway may pave the way for the development of novel diagnostics and therapeutics for MASLD.

Hepatic HKDC1 Deletion Alleviates Western Diet-Induced MASH in Mice

The global prevalence of Metabolic dysfunction-associated steatohepatitis (MASH) has been rising sharply, closely mirroring the increasing rates of obesity and metabolic syndrome. MASH exhibits a strong sexual dimorphism where females are affected with more severe forms after menopause. Hexokinase domain-containing protein 1 (HKDC1) has recently been recognized for its role in liver diseases, where its expression is minimal under normal conditions but significantly increases in response to metabolic stressors like obesity and liver injury. This selective upregulation suggests HKDC1s potential specialization in hepatic glucose and lipid dysregulation, linking it closely to the progression of MASLD and MASH. This study aims to clarify the role of HKDC1 in Western diet-induced MASH in female mice by examining its impact on hepatic glucose and lipid metabolism, offering insights into its potential as a therapeutic target and addressing the need for sex-specific research in liver disease. This study reveals that HKDC1 expression is elevated in obese women with MASH and correlates with liver pathology. In a mouse model, liver-specific HKDC1 knockout (HKDC1LKO) protected against Western diet-induced obesity, glucose intolerance, and MASH features, including steatosis, inflammation, and fibrosis. Transcriptomic analysis showed that HKDC1 deletion reduced pro-inflammatory and pro-fibrotic gene expression, while gut microbiome analysis indicated a shift toward MASH-protective bacteria. These findings suggest that HKDC1 may exacerbate MASH progression through its role in metabolic and inflammatory pathways, making it a potential therapeutic target.

Sex differences in murine MASH induced by a fructose-palmitate-cholesterol-enriched diet

Background & Aims

Metabolic syndrome-associated steatotic liver disease (MASLD) and metabolic syndrome-associated steatohepatitis (MASH) have global prevalence rates exceeding 25% and 3-6%, respectively. The introduction of high-fructose corn syrup to the diet in the 1970s has been linked to metabolic and hepatic disturbances. Despite these associations, the potential for sex-dependent responses resulting from fructose-containing diets on MASLD/MASH has not been addressed.

Methods

Female and male C57BL/6J mice were fed a fructose-palmitate-cholesterol (FPC)-NASH diet vs. standard chow for 16 weeks (n = 40 mice). At sacrifice, plasma and liver were retrieved, the latter for single-nucleus RNA sequencing. Publicly available data sets of human male and female MASH liver were probed.

Results

The FPC-NASH diet-induced metabolic dysfunction in both female and male mice, with females exhibiting more severe hepatic steatosis (p = 0.0262), inflammation (p = 0.0206), and fibrosis (p <0.0001). Single-nucleus RNA sequencing revealed distinct sex-specific transcriptional profiles in hepatocytes and stellate cells responding to the FPC-NASH diet compared to the standard chow. In female mice, compared to males, pathways associated with lipid and metabolic processes in hepatocytes and cell-cell communication and adhesion in stellate cells were enriched. Metabolic flux analyses demonstrated reduced bile acid metabolism in female mice and human hepatocytes in FPC-NASH and MASH conditions, respectively, compared to their male counterparts.

Conclusions

Molecular profiling of hepatocytes and stellate cells in FPC-NASH diet-fed mice revealed significant sex differences mirrored in human MASH. The identification of intrinsic, within-sex, diet-dependent disparities underscores the critical need to include both male and female individuals in MAFLD/MASH studies and clinical trials.

Impact and implications

Despite the importance of metabolic dysfunction-associated steatohepatitis (MASH) in impairment of human health, the potential for and mechanisms of sex-dependent responses have yet to be well-studied, particularly with respect to the possible influence of high-fructose corn syrup additives to the diet, which has been linked to metabolic and hepatic disturbances. In a mouse model of fructose supplementation to a NASH diet, female mice displayed significantly higher MASH scores (steatosis, inflammation and fibrosis) compared to male mice. Single-nucleus RNA sequencing of livers revealed intrinsic, diet-dependent molecular disparities within sex, which were exaggerated when comparing female vs. male mice fed the fructose-containing NASH diet; many of these findings were recapitulated in human female vs. male patients with MASH. These results highlight potential mechanistic explanations and therapeutic targets for addressing sex differences and underscore the need to study both sexes in animal models and human MASH.

Diagnostic Accuracy of CT for the Detection of Hepatic Steatosis: A Systematic Review and Meta-Analysis

Background CT plays an important role in the opportunistic identification of hepatic steatosis. CT performance for steatosis detection has been inconsistent across various studies, and no clear guidelines on optimum thresholds have been established. Purpose To conduct a systematic review and meta-analysis to assess CT diagnostic accuracy in hepatic steatosis detection and to determine reliable cutoffs for the commonly mentioned measures in the literature. Materials and Methods A systematic search of the PubMed, Embase, and Scopus databases (English-language studies published from September 1977 to January 2024) was performed. Studies evaluating the diagnostic accuracy of noncontrast CT (NCCT), contrast-enhanced (CECT), and dual-energy CT (DECT) for hepatic steatosis detection were included. Reference standards included biopsy, MRI proton density fat fraction (PDFF), or NCCT. In several CECT and DECT studies, NCCT was used as the reference standard, necessitating subgroup analysis. Statistical analysis included a random-effects meta-analysis, assessment of heterogeneity with use of the I2 statistic, and meta-regression to explore potential sources of heterogeneity. When available, mean liver attenuation, liver-spleen attenuation difference, liver to spleen attenuation ratio, and the DECT-derived fat fraction for hepatic steatosis diagnosis were assessed. Results Forty-two studies (14 186 participants) were included. NCCT had a sensitivity and specificity of 72% and 88%, respectively, for steatosis (>5% fat at biopsy) detection and 82% and 94% for at least moderate steatosis (over 20%-33% fat at biopsy) detection. CECT had a sensitivity and specificity of 66% and 90% for steatosis detection and 68% and 93% for at least moderate steatosis detection. DECT had a sensitivity and specificity of 85% and 88% for steatosis detection. In the subgroup analysis, the sensitivity and specificity for detecting steatosis were 80% and 99% for CECT and 84% and 93% for DECT. There was heterogeneity among studies focusing on CECT and DECT. Liver attenuation less than 40-45 HU, liver-spleen attenuation difference less than -5 to 0 HU, and liver to spleen attenuation ratio less than 0.9-1 achieved high specificity for detection of at least moderate steatosis. Conclusion NCCT showed high performance for detection of at least moderate steatosis. © RSNA, 2024 Supplemental material is available for this article.

Prevalence and Correlates of Probable Nonalcoholic Steatohepatitis (NASH) in Pars Cohort Study

BACKGROUND

Studies on the prevalence of nonalcoholic steatohepatitis (NASH) and the factors associated with its high prevalence among Iranian people are limited. This study evaluated the prevalence of NASH and its associated factors among Iranian adults using Pars Cohort Study (PCS) data.

METHODS

This cross-sectional study was conducted based on PCS, which includes 40-75-year-old adults from the Valashahr area. NASH was defined as alanine aminotransferase (ALT) higher than 40 U/L without evidence of hepatitis B or C infections. The prevalence of NASH and its associations with basic and demographic characteristics, socioeconomic characteristics, medical history, gastrointestinal symptoms, and laboratory tests were evaluated.

RESULTS

Overall, 8734 patients, including 3917 men (44.8%), were enrolled in this study. The mean age of participants was 52.62 years (SD=9.68), and 605 individuals had NASH (6.9%). In the regression analysis, in contrast to female gender (OR=0.31, 95% CI=0.249‒0.386, P<0.001) and age (OR=0.951, 95% CI=0.941‒0.962, P<0.001), history of heart disease (OR=1.499, 95% CI=1.146‒1.962, P=0.003), history of diabetes (OR=1.523, 95% CI=1.162‒1.995, P=0.002), hypertension (OR=1.241, 95% CI=1.023‒1.506, P=0.029), being overweight or obese (OR=2.192, 95% CI=1.755‒2.737, P<0.001), being in the richest or second richest wealth index quantiles (OR=1.315, 95% CI=1.107‒1.156, P=0.002), and increased waist circumference (OR=1.409, 95% CI=1.107‒1.793, P<0.005) were independently associated with a higher risk of having NASH.

CONCLUSION

In this study, we determined the prevalence of NASH and found male gender, younger age, history of heart disease, history of diabetes, hypertension, socioeconomic status, and obesity as possible factors associated with a higher risk of NASH among Iranians.

Cytokeratin 18 in nonalcoholic fatty liver disease: value and application

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is a common metabolism-related disease worldwide. Although studies have shown that some medications may be effective for treating NAFLD, they do not satisfy the medical requirements, and lifestyle changes are the most basic strategy. Thus, early detection of NAFLD and timely lifestyle interventions are highly important.

AREAS COVERED

The traditional diagnostic methods for NAFLD are limited by accuracy, cost, and security issues. Cytokeratin 18 (CK18), which is a marker of apoptosis and overall cell death, is an excellent biomarker for NAFLD. Liver fat accumulation in NAFLD triggers the activation of caspases, which increases the CK18 cleavage and its release into the blood. CK18 can help diagnose different stages of NAFLD, especially the nonalcoholic steatohepatitis (NASH) stage. In evaluating the efficacy of the NAFLD treatment and predicting the risk of NAFLD-related diseases, CK18 plays a significant role.

EXPERT OPINION

CK18 can non-invasively monitor the pathological conditions of NAFLD patients and provide new hope for the early diagnosis of NAFLD. Adding CK18 to the NAFLD diagnostic criteria that are widely used in clinical settings may be efficient for the detection of NAFLD and early effective intervention.

Interaction between non-alcoholic fatty liver disease and obesity on the risk of developing cardiovascular diseases

BACKGROUNDS

This investigation seeks to explore the correlation between nonalcoholic fatty liver disease (NAFLD) and cardiovascular diseases (CVDs), and to to provide evidence for the prevention and treatment of CVDs.

METHODS

This study utilized data from the Jinchang cohort platform, including 19,399 participants without pre-existing major CVDs. Based on the general population and gender stratification, Cox models were used to analyze the risk of NAFLD for CVDs. The combined effect of NAFLD and different obesity indicators on CVDs was analyzed by additive and multiplicative interaction models and subgroups.

RESULTS

There were 3129 NAFLD patients out of 19399 subjects, and 723 (23.11%) of them had the CVD. After adjusting for multiple confounding factors, the Cox model revealed a 1.17-fold increase in the risk of CVDs among patients with NAFLD compared to those without NAFLD. Moreover, there was no notable disparity in CVDs risk among most NAFLD patients at the same level of obesity. The results indicated no additive interaction between NAFLD and obesity concerning CVDs risk, but rather a positive multiplicative interaction. Using the normal population as a reference, it was found that people with both obesity and NAFLD significantly increased the risk of developing CVDs, with HRs and 95% CIs of 1.790 (1.508, 2.126), 1.356 (1.213, 1.517), and 1.807 (1.503, 2.174), respectively, for BMI, WC, and the combination of BMI and WC.

CONCLUSIONS

NAFLD and obesity are independent risk factors for CVDs. The synergy of obesity and NAFLD implies that NAFLD patients should control weight gain. Larger BMI and WC values may increase the CVDs risk for NAFLD patients, especially women.

The Influence of Urbanization on the Patterns of Hepatocellular Carcinoma Mortality From 1999 to 2020

Background

Hepatocellular carcinoma (HCC) remains one of the leading causes of cancer-related fatalities despite early diagnosis and treatment progress, creating a significant public health issue in the United States. This investigation utilized death certificate data from the Centers for Disease Control and Prevention Wide-ranging Online Data for Epidemiologic Research (CDC WONDER) database to investigate HCC mortality patterns and death locations from 1999 to 2020. The objective was to analyze trends in HCC mortality across different population groups, considering the impact of urbanicity.

Methods

In this study, death certificate data obtained from the CDC WONDER database were utilized to investigate the trends in HCC mortality and location of death between 1999 and 2020. The annual percent change (APC) method was applied to estimate the average annual rate of change during the specified timeframe for the relevant health outcome. Furthermore, including data on the location of death and geographic areas allowed us to gain deeper insights into the patterns and characteristics of HCC and its impact on different regions.

Results

Between 1999 and 2020, there were 184,073 reported deaths attributed to HCC, and data on the location of death were available for all cases. Most deaths occurred during inpatient admissions (34.93%) or at home (41.19%). The study also found that the highest age-adjusted mortality rate (AAMR) for HCC was observed among male patients, particularly among those identified as Asian or Pacific Islander. Variations in AAMR were determined based on the level of urbanization or rurality of the area, with higher rates observed in more densely populated and urbanized regions. In contrast, less urbanized and populated areas experienced a profound increase in AAMR over the past two decades.

Conclusion

The HCC-related AAMRs have worsened over time for most ethnic groups, except for Asian or Pacific Islanders, which showed a reduction in APC despite having the worst AAMR. Although rural and less densely populated areas have substantially increased AAMR over the past two decades, more urbanized areas continued to have higher AAMR rates.

Cost-Effectiveness Analysis of Innovative Therapies for Patients with Non-Alcoholic Fatty Liver Disease

OBJECTIVE

Currently there are no disease-specific approved therapies for non-alcoholic fatty liver (NAFL) and non-alcoholic steatohepatitis (NASH); however, several treatments are under development. This study aimed to estimate the cost-effectiveness of hypothetical innovative therapies compared with lifestyle intervention alone and combined with pioglitazone, and assess the health economic consequences of their future availability for patients.

METHODS

A Markov cohort model was developed, considering fourteen disease health states and one absorbing state representing death. Transition probabilities, costs, utilities, and treatment efficacy were based on published data and assumptions. Four treatment strategies were considered, including two existing therapies (lifestyle intervention, small molecule treatment) and two hypothetical interventions (biological and curative therapy). The analysis was performed from the US third-party payer perspective.

RESULTS

The curative treatment with the assumed efficacy of 70% of patients cured and assumed price of $500,000 was the only cost-effective option. Although it incurred higher costs (a difference of $188,771 vs. lifestyle intervention and $197,702 vs. small molecule), it generated more QALYs (a difference of 1.58 and 1.38 QALYs, respectively), resulting in an ICER below the willingness-to-pay threshold of $150,000 per QALY. The sensitivity analyses showed that the results were robust to variations in model parameters.

CONCLUSIONS

This study highlighted the potential benefits of therapies aimed at curing a disease rather than stopping its progression. Nonetheless, each of the analyzed therapies could be cost-effective compared with lifestyle intervention at a relatively high price.

Sex-based differences in natural killer T cell-mediated protection against diet-induced steatohepatitis in Balb/c mice

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) is prevalent in Western countries, evolving into metabolic dysfunction-associated steatohepatitis (MASH) with a sexual dimorphism. Fertile women exhibit lower MASLD risk than men, which diminishes post-menopause. While NKT-cell involvement in steatohepatitis is debated, discrepancies may stem from varied mouse strains used, predominantly C57BL6/J with Th1-dominant responses. Exploration of steatohepatitis, encompassing both genders, using Balb/c background, with Th2-dominant immune response, and CD1d-deficient mice in the Balb/c background (lacking Type I and Type II NKT cells) can clarify gender disparities and NKT-cell influence on MASH progression.

METHODS

A high fat and choline-deficient (HFCD) diet was used in male and female mice, Balb/c mice or CD1d-/- mice in the Balb/c background that exhibit a Th2-dominant immune response. Liver fibrosis and inflammatory gene expression were measured by qPCR, and histology assessment. NKT cells, T cells, macrophages and neutrophils were assessed by flow cytometry.

RESULTS

Female mice displayed milder steatohepatitis after 6 weeks of HFCD, showing reduced liver damage, inflammation, and fibrosis compared to males. Male Balb/c mice exhibited NKT-cell protection against steatohepatitis whereas CD1d-/- males on HFCD presented decreased hepatoprotection, increased liver fibrosis, inflammation, neutrophilic infiltration, and inflammatory macrophages. In contrast, the NKT-cell role was negligible in early steatohepatitis development in both female mice, as fibrosis and inflammation were similar despite augmented liver damage in CD1d-/- females. Relevant, hepatic type I NKT levels in female Balb/c mice were significantly lower than in male.

CONCLUSIONS

NKT cells exert a protective role against experimental steatohepatitis as HFCD-treated CD1d-/- males had more severe fibrosis and inflammation than male Balb/c mice. In females, the HFCD-induced hepatocellular damage and the immune response are less affected by NKT cells on early steatohepatitis progression, underscoring sex-specific NKT-cell influence in MASH development.

Clinical characteristics in patients with non-alcoholic steatohepatitis in Japan: a case-control study using a 5-year large-scale claims database

OBJECTIVES

To examine the clinical characteristics of patients with non-alcoholic steatohepatitis (NASH) and associated comorbidities.

DESIGN

A case-control study using the national health insurance and the long-term elderly health insurance claims database.

SETTING

Eligible patients diagnosed with NASH (ICD-10 K-75.8, other inflammatory liver disease or K-76.0, other fatty liver) between April 2015 and March 2020 were included.

PARTICIPANTS

Patients who met the diagnostic definitions for NASH (n=545) were matched with non-NASH controls (n=185 264) and randomly selected according to sex, birth year and residential area.

INTERVENTIONS

No interventions were made.

PRIMARY AND SECONDARY OUTCOME MEASURES

ORs were estimated for the relationship between patient background, such as age and sex, body mass index (BMI), NASH-related comorbidities and lifestyle-related diseases.

RESULTS

In total, 545 patients with NASH (38.3% men) and 185 264 non-NASH controls (43.2% men) were identified, with median ages of 68 (IQR 63.0-75.0) and 65 (IQR 44.0-74.0) years, respectively. BMI was significantly higher in patients with NASH than in controls (25.8 kg/m2 vs 22.9 kg/m2, p<0.001). The proportions of women, patients with hypertension, patients with dyslipidaemia and patients with type 2 diabetes were higher in the NASH group. In addition, NASH was associated with an increased risk of hepatic cirrhosis (OR 28.81 (95% CI 21.79 to 38.08)), followed by liver cancer (OR 18.38 (95% CI 12.56 to 26.89)). There was no significant association between NASH and risk for depression (OR 1.11 (95% CI 0.87 to 1.41)), insomnia (OR 1.12 (95% CI 0.94 to 1.34)) or chronic kidney diseases (OR 0.81 (95% CI 0.58 to 1.12)).

CONCLUSIONS

In the daily medical care of patients, it is necessary to consider sex and age differences and to pay close attention to the risk of liver cancer, as well as other lifestyle-related comorbidities associated with NASH.

Nonalcoholic Fatty Liver Disease and Omega-3 Fatty Acids: Mechanisms and Clinical Use

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic fatty liver disease worldwide, particularly in obese and type 2 diabetic individuals. Currently, there are no therapies for NAFLD that have been approved by the US Food and Drug Administration. Herein, we examine the rationale for using ω3 polyunsaturated fatty acids (PUFAs) in NAFLD therapy. This focus is based on the finding that NAFLD severity is associated with a reduction of hepatic C20-22 ω3 PUFAs. Because C20-22 ω3 PUFAs are pleiotropic regulators of cell function, loss of C20-22 ω3 PUFAs has the potential to significantly impact hepatic function. We describe NAFLD prevalence and pathophysiology as well as current NAFLD therapies. We also present evidence from clinical and preclinical studies that evaluated the capacity of C20-22 ω3 PUFAs to treat NAFLD. Given the clinical and preclinical evidence, dietary C20-22 ω3 PUFA supplementation has the potential to decrease human NAFLD severity by reducing hepatosteatosis and liver injury.

Non-alcoholic Steatohepatitis in Asians: Current Perspectives and Future Directions

Non-alcoholic steatohepatitis (NASH) is a subset of non-alcoholic fatty liver disease (NAFLD), which, apart from excess fat in the liver, may be characterised by some level of inflammatory infiltration and fibrogenesis, occasionally progressing to liver cirrhosis or hepatocellular carcinoma (HCC). The objective of the current review is to elucidate the rising prevalence, the role of microbiome and genetics in pathogenesis, diagnostic challenges, and novel treatment alternatives for NASH. Newer diagnostic techniques are being developed since using liver biopsy in a larger population is not a reasonable option and is primarily restricted to clinical research, at least in developing countries. Besides these technical challenges, another important factor leading to deviation from guideline practice is the lack of health insurance coverage in countries like India. It leads to reluctance on the part of physicians and patients to delay required tests to curb out-of-pocket expenditure. There is no cure for NASH, with liver transplantation remaining the last option for those who progress to end-stage liver disease (ESLD) or are detected with early-stage HCC. Thus, lifestyle modification remains the only viable option for many, but compliance and long-term adherence remain major challenges. In obese individuals, bariatric surgery and weight reduction have shown favourable results. In patients with less severe obesity, endoscopic bariatric metabolic therapies (EBMT) are rapidly emerging as less invasive therapies. However, access and acceptability remain poor for these weight reduction methods. Therefore, intense research is being conducted for potential newer drug classes with several agents currently in phase II or III of clinical development. Some of these have demonstrated promising results, such as a reduction in hepatic fat content, and attenuation of fibrosis with an acceptable tolerability profile in phase II studies. The developments in the management of NASH have been fairly encouraging. Further well-designed long-term prospective studies should be undertaken to generate evidence with definitive results.

Treatment responses and outcomes in patients with autoimmune hepatitis and concomitant features of non-alcoholic fatty liver disease

Background & Aims

Non-alcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH) affect 17-46% of Western countries, making coexistence with other liver diseases inevitable. We investigated the prevalence and clinical significance of NAFLD/NASH or the components of metabolic syndrome (MetS) in a large multicentric cohort of patients with autoimmune hepatitis (AIH).

Methods

Data from six academic centres (Greece, Canada, Japan, Germany, The Netherlands, and Spain) were evaluated. The presence of NAFLD/NASH in liver biopsy, MetS components, and clinical and laboratory parameters were recorded.

Results

A total of 640 patients (474 females, age 49 [4-87] years; follow-up 78 [1-521] months) were included. NAFLD was present in 146 (22.8%) patients (AIH/non-alcoholic fatty liver [NAFL] 115 [18%], AIH/NASH 31 [4.8%]). AIH/NAFL patients were older (p = 0.017), more frequently overweight or obese (p = 0.002), had hypertension (p = 0.001), and had diabetes (p = 0.016), whereas they less frequently had acute presentation (p = 0.002) and soluble liver antigen/liver pancreas positivity (p <0.05), lower transaminases (p <0.001), ALP (p = 0.028) and IgG (p = 0.004) and higher albumin (p <0.001) than patients with AIH only. Patients with AIH/NASH more frequently had cirrhosis at diagnosis (p = 0.036) and higher IgG (p = 0.009). Response to treatment did not differ between groups. Patients with cirrhosis with AIH/NAFL had higher frequency of decompensation compared with patients with AIH only (p <0.05). Patients with type 2 diabetes mellitus and dyslipidaemia had increased hazard of disease progression (p <0.05 for each).

Conclusions

The prevalence of NAFLD in AIH is similar to the general population. Concurrence of NASH in patients with AIH signifies a more severe disease, whereas that of NAFL may indicate a worse prognosis in patients with cirrhosis. T2DM and dyslipidaemia in AIH patients are associated with dismal parameters of outcome. Our findings suggest that NAFLD presence or even components of MetS in patients with AIH may affect prognosis, so closer follow-up of such patients is warranted.

Impact and implications

Non-alcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH) affect many people, making coexistence with other liver diseases inevitable. We investigated the prevalence and clinical significance of NAFLD/NASH or the components of metabolic syndrome (MetS) in patients with autoimmune hepatitis (AIH). NAFLD and NASH presence in patients with AIH is as frequent as in the general population. The concurrence of NASH in patients with AIH seems to signify a more severe disease, whereas that of non-alcoholic fatty liver may indicate a worse prognosis in a specific subgroup of patients who already have cirrhosis at diagnosis. Diabetes or dyslipidaemia in patients with AIH were associated with worse prognosis. Therefore, it seems that closer follow-up of patients with concurrent AIH and NAFLD or AIH and components of MetS is needed.

Gender Differences in a Mouse Model of Hepatocellular Carcinoma Revealed Using Multi-Modal Imaging

The worldwide incidence of hepatocellular carcinoma (HCC) continues to rise, in part due to poor diet, limited exercise, and alcohol abuse. Numerous studies have suggested that the loss or mutation of PTEN plays a critical role in HCC tumorigenesis through the activation of the PI3K/Akt signaling axis. The homozygous knockout of PTEN in the livers of mice results in the accumulation of fat (steatosis), inflammation, fibrosis, and eventually progression to HCC. This phenotype bears a striking similarity to non-alcoholic steatohepatitis (NASH) which is thought to occupy an intermediate stage between non-alcoholic fatty liver disease (NAFLD), fibrosis, and HCC. The molecular and physiological phenotypes that manifest during the transition to HCC suggest that molecular imaging could provide a non-invasive screening platform to identify the hallmarks of HCC initiation prior to the presentation of clinical disease. We have carried out longitudinal imaging studies on the liver-specific PTEN knockout mouse model using CT, MRI, and multi-tracer PET to interrogate liver size, steatosis, inflammation, and apoptosis. In male PTEN knockout mice, significant steatosis was observed as early as 3 months using both magnetic resonance spectroscopy (MRS) and computed tomography (CT). Enhanced uptake of the apoptosis tracer 18F-TBD was also observed in the livers of male PTEN homozygous knockout mice between 3 and 4 months of age relative to heterozygous knockout controls. Liver uptake of the inflammation tracer [18F]4FN remained relatively low and constant over 7 months in male PTEN homozygous knockout mice, suggesting the suppression of high-energy ROS/RNS with PTEN deletion relative to heterozygous males where the [18F]4FN liver uptake was elevated at early and late time points. All male PTEN homozygous mice developed HCC lesions by month 10. In contrast to the male cohort, only 20% (2 out of 10) of female PTEN homozygous knockout mice developed HCC lesions by month 10. Steatosis was significantly less pronounced in the female PTEN homozygous knockout mice relative to males and could not accurately predict the eventual occurrence of HCC. As with the males, the [18F]4FN uptake in female PTEN homozygous knockout mice was low and constant throughout the time course. The liver uptake of 18F-TBD at 3 and 4.5 months was higher in the two female PTEN knockout mice that would eventually develop HCC and was the most predictive imaging biomarker for HCC in the female cohort. These studies demonstrate the diagnostic and prognostic role of multi-modal imaging in HCC mouse models and provide compelling evidence that disease progression in the PTEN knockout model is highly dependent on gender.

The Influence of Sex Hormones in Liver Function and Disease

The liver performs a multitude of bodily functions, whilst retaining the ability to regenerate damaged tissue. In this review, we discuss sex steroid biology, regulation of mammalian liver physiology and the development of new model systems to improve our understanding of liver biology in health and disease. A major risk factor for the development of liver disease is hepatic fibrosis. Key drivers of this process are metabolic dysfunction and pathologic activation of the immune system. Although non-alcoholic fatty liver disease (NAFLD) is largely regarded as benign, it does progress to non-alcoholic steatohepatitis in a subset of patients, increasing their risk of developing cirrhosis and hepatocellular carcinoma. NAFLD susceptibility varies across the population, with obesity and insulin resistance playing a strong role in the disease development. Additionally, sex and age have been identified as important risk factors. In addition to the regulation of liver biochemistry, sex hormones also regulate the immune system, with sexual dimorphism described for both innate and adaptive immune responses. Therefore, sex differences in liver metabolism, immunity and their interplay are important factors to consider when designing, studying and developing therapeutic strategies to treat human liver disease. The purpose of this review is to provide the reader with a general overview of sex steroid biology and their regulation of mammalian liver physiology.

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

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

Relationship between Being Overweight and Clinical Outcomes of Ablation Therapy for Hepatocellular Carcinoma under Ultrasound Guidance: A Retrospective Analysis

This study aimed to investigate the effect of being overweight on the outcome of ablation therapy for patients with early-stage hepatocellular carcinoma (HCC). This retrospective study included 198 patients with HCC who underwent radiofrequency ablation or microwave ablation at Gunma Saiseikai Maebashi Hospital between April 2017 and December 2021. We divided the patients into two groups based on their body mass index (BMI): overweight (BMI ≥ 25 kg/m2, n = 74 (37.4%)) and non-overweight (BMI < 25 kg/m2, n = 124 (62.6%)). The technical success rates (TSRs) in the first session were 78.4% and 90.3% in overweight and non-overweight patients, respectively, with a significant difference (p = 0.03). Additional ablation therapy for residual tumors was required in 15 (20.3%) overweight and 11 (8.9%) non-overweight patients (p = 0.03), resulting in 95.9% and 99.2% TSRs at the final session, respectively, without a significant difference (p = 0.3). While local tumor progression and distant recurrence rates were not significantly different between the two groups, overall survival was better in overweight patients than in non-overweight patients (p < 0.001). Despite the potential adverse impact of being overweight on public health problems, the present findings showed the relationship between being overweight and improved survival. The negative aspects of being overweight might remain as minor technical issues in HCC patients receiving ablation therapy.

Evaluation of metabolic dysfunction-associated fatty liver disease using FibroScan, diet, and microbiota: A large cross-sectional study

OBJECTIVE

We evaluated the clinical characteristics of metabolic dysfunction-associated fatty liver disease (MAFLD) to evaluate the usefulness of the MAFLD diagnostic criteria in a resident health survey.

METHODS

In 1056 participants of a health survey, we compared obesity, diabetes, metabolic dysregulation, FibroScan-aspartate aminotransferase (FAST) score, dietary habits, and gut microbiota between healthy individuals and participants with MAFLD and Nonalcoholic fatty liver disease (NAFLD).

RESULTS

The proportion of participants with MAFLD in the fatty liver was higher than that with NAFLD (88.1% vs. 75.5%, respectively). Of 36 participants with a FAST score > 0.35, 29 (80.6%) participants had MAFLD and 23 (63.9%) participants had NAFLD. Of 29 patients with liver fibrosis, 26 (89.7%) participants had obesity and metabolic dysregulation. In the evaluation of diet, the total energy, protein, dietary fiber, and salt intake were significantly higher in participants with MAFLD than those in participants without fatty liver. In the microbiota analysis, the results of the linear discriminant analysis effect size analysis revealed nine bacterial genera that were significantly different in participants with MAFLD in comparison with participants without fatty liver. Of these genera, the relative abundance of Blautia was especially low in participants with MAFLD.

CONCLUSION

In a resident health survey, participants with MAFLD had a higher proportion of fatty liver than those with NAFLD. MAFLD criteria could help in improved screening of participants with liver fibrosis. Therefore, the MAFLD criteria could be a useful diagnostic tool for aggressively identifying participants with a high risk of fatty liver. Additionally, Blautia might be involved in the development of MAFLD.

Pathophysiological Role of Chymase-Activated Matrix Metalloproteinase-9

Chymase present in mast cells can directly form matrix metalloproteinase (MMP)-9 from proMMP-9. Chymase-activated MMP-9 has been reportedly closely related to the pathogenesis of various diseases, and inflammation-related diseases in particular. Upregulated chymase and MMP-9 have been observed in tissues from patients and animal models of aortic aneurysm, inflammatory gastrointestinal and hepatic diseases, acute pancreatic failure, atopic dermatitis and rheumatoid arthritis. Chymase at these regions is only derived from mast cells, while MMP-9 is derived from macrophages and neutrophils in addition to mast cells. Chymase inhibitors attenuate MMP-9 formation from pro-MMP-9, and ameliorate the development and progression of these disorders, along with reduction in inflammatory cell numbers. MMP-9 activated by chymase might also be involved in angiogenesis in the tumor environment. Development of angiogenesis around several cancers is closely related to the expression of chymase and MMP-9, and postoperative survival curves have revealed that patients with a higher number of chymase positive cells have lower survival rates. In this review, we wanted to clarify the role of chymase-activated MMP-9, which might become an important therapeutic target for various inflammatory disorders.

A machine-learning approach for nonalcoholic steatohepatitis susceptibility estimation

BACKGROUND

Nonalcoholic steatohepatitis (NASH), a severe form of nonalcoholic fatty liver disease, can lead to advanced liver damage and has become an increasingly prominent health problem worldwide. Predictive models for early identification of high-risk individuals could help identify preventive and interventional measures. Traditional epidemiological models with limited predictive power are based on statistical analysis. In the current study, a novel machine-learning approach was developed for individual NASH susceptibility prediction using candidate single nucleotide polymorphisms (SNPs).

METHODS

A total of 245 NASH patients and 120 healthy individuals were included in the study. Single nucleotide polymorphism genotypes of candidate genes including two SNPs in the cytochrome P450 family 2 subfamily E member 1 (CYP2E1) gene (rs6413432, rs3813867), two SNPs in the glucokinase regulator (GCKR) gene (rs780094, rs1260326), rs738409 SNP in patatin-like phospholipase domain-containing 3 (PNPLA3), and gender parameters were used to develop models for identifying at-risk individuals. To predict the individual's susceptibility to NASH, nine different machine-learning models were constructed. These models involved two different feature selections including Chi-square, and support vector machine recursive feature elimination (SVM-RFE) and three classification algorithms including k-nearest neighbor (KNN), multi-layer perceptron (MLP), and random forest (RF). All nine machine-learning models were trained using 80% of both the NASH patients and the healthy controls data. The nine machine-learning models were then tested on 20% of both groups. The model's performance was compared for model accuracy, precision, sensitivity, and F measure.

RESULTS

Among all nine machine-learning models, the KNN classifier with all features as input showed the highest performance with 86% F measure and 79% accuracy.

CONCLUSIONS

Machine learning based on genomic variety may be applicable for estimating an individual's susceptibility for developing NASH among high-risk groups with a high degree of accuracy, precision, and sensitivity.

Mechanisms of nonalcoholic steatohepatitis-associated cardiomyopathy: key roles for liver-heart crosstalk

PURPOSE OF REVIEW

Nonalcoholic steatohepatitis (NASH) is a multisystem disease that affects not only the liver but also heart, pancreas, and kidney. We currently lack a comprehensive understanding of mechanisms responsible for the development of NASH-associated cardiomyopathy or the influence of sex on pathophysiology. There is a critical need to address these gaps in knowledge in order to accelerate translation of knowledge into clinical practice.

RECENT FINDINGS

NASH and cardiovascular disease share common risk factors such as chronic inflammation, hyperlipidemia, and insulin resistance. Early cardiac dysfunction in NASH that is independent of obesity or other cardiometabolic risk factors suggests roles for liver-heart crosstalk in disease pathogenesis. Inflammation is a driving force in the pathogenesis of NASH, and it is likely that 'spill over' of NASH inflammation contributes to the development of cardiomyopathy. However, molecular and cellular mechanisms that mediate NASH-associated cardiomyopathy remain unclear because of inherent limitations of experimental models. Even so, recent studies implicate inflammatory, metabolic, and physiologic mechanisms that enhance our understanding of NASH-associated cardiomyopathy and the role of liver-heart crosstalk.

SUMMARY

An innovative, detailed, and mechanistic understanding of NASH-associated cardiomyopathy is relevant to public health and will be fundamental for the comprehensive care of these patients.

Relation of Dietary Patterns and Nutritional Profile to Hepatic Fibrosis in a Sample of Lebanese Non-Alcoholic Fatty Liver Disease Patients

Non-alcoholic fatty liver disease (NAFLD) is considered the most common liver injury worldwide. NAFLD can evolve into non-alcoholic steatohepatitis (NASH) with or without fibrosis. The objectives of this study were to determine the nutritional profile and dietary patterns of NAFLD Lebanese patients and to report the type of diet-related to the presence of hepatic fibrosis. We hypothesized that the traditional pattern was related to a low risk of fibrosis. This cross-sectional study included 320 eligible Lebanese NAFLD patients. Three dietary patterns were identified: the Traditional diet, the High Fruit diet, and the Westernized diet. Multivariate analysis showed a significant relationship between high adherence to the traditional diet and absence of hepatic fibrosis with a decreased risk of 82%, p = 0.031 after adjusting for its covariables. Fruits were absent from this dietary pattern. Although our results pointed to a possible relationship between fibrosis in NAFLD patients and fruit intake, experimental studies are needed to show whether this is a causal relationship. However, the results obtained in this study may contribute to the planning of dietary interventions and recommendations and enable a better follow-up for NAFLD patients with fibrosis.

[A patient with rheumatoid arthritis who developed liver cirrhosis after increased soft drinks intake]

A Japanese woman in her 80s with rheumatoid arthritis (RA) was admitted for weakness, edema, and ascites. She was obese (148 cm in height, 60 kg in weight) and had a high gamma-glutamyltransferase level according to her laboratory findings before treatment. She had received methotrexate (MTX) at a dose of 6 mg/week for 1 year and 9 months. She had consumed large amounts of soft drinks (about 110 g of sugar/day) for a long time, but during the course of treatment for RA, she began drinking even more (170 g/day). Her condition improved with the discontinuation of MTX, adequate nutrition, and administration of diuretics. We diagnosed her with liver cirrhosis caused by both drug-induced hepatic injury due to MTX and by exacerbation of non-alcoholic steatohepatitis due to excessive sugar intake.

Placebo effect on progression and regression in NASH: Evidence from a meta-analysis

BACKGROUND AND AIMS

The evaluation of the natural history of NASH has been limited. Currently, liver biopsy remains the gold standard in the assessment of NASH. Placebo-controlled trials represent a controlled environment with paired biopsies for the evaluation of NASH. This meta-analysis thus seeks to quantify the change severity of NASH over time, with patients on placebo arms from randomized controlled trials (RCTs) to examine the natural history of NASH.

METHODS

A search was conducted to include NASH RCTs with placebo treatment arms. Primary outcomes were (1) the resolution of NASH without worsening of fibrosis, (2) two-point reduction in NAFLD activity score without worsening of fibrosis, and (3) at least one-point reduction in fibrosis. Generalized linear mix model was used to estimate pooled proportion and mean differences.

RESULTS

This meta-analysis of 43 RCTs included 2649 placebo-treated patients. The pooled estimate of NASH resolution and two-point NAFLD activity score reduction without worsening of fibrosis was 11.65% (95% CI: 7.98-16.71) and 21.11% (95% CI: 17.24-25.57). The rate of ≥1 stage reduction and progression of fibrosis was 18.82% (95% CI: 15.65-22.47) and 22.74% (CI: 19.63-26.17), respectively. Older age and African American ethnicity was associated with lower NASH resolution rate in placebo-treated patients.

CONCLUSIONS

Despite the absence of any pharmacological interventions, a significant proportion of patients in the placebo arm demonstrated improvements in liver histology, highlighting the possibility that NASH is a disease that can not only progress but regress spontaneously over time. Additionally, histologic response in placebo-treated patients is helpful in future design of phase 2B and phase 3 trials.

Premenopausal Syndrome and NAFLD: A New Approach Based on Gender Medicine

Non-alcoholic fatty liver disease (NAFLD) is a multifactorial condition that affects 25% of the world's population. There is a clear difference in both geographical distribution and sex in childbearing age. These differences are reduced when women become older and senescence begins. The factors that affect the likelihood of developing NAFLD in a premenopausal woman are an imbalance of sex hormones (especially in estradiol and androgen), microbiome dysregulation, insulin resistance, early menarche, the length of time that the woman breastfeeds for and polycystic ovarian syndrome (PCOS). The aim of this review is to identify various physical ailments that may not appear to be serious to young women but that then affect the onset of NAFLD in perimenopause and can degenerate into NASH. These conditions should also be considered in future clinical management, as well as in research opportunities, in order to customize the monitoring and treatment of NAFLD, considering gender medicine for those women who had early metabolic symptoms that were not considered to be significant at the time.

Additional Effect of Luseogliflozin on Semaglutide in Nonalcoholic Steatohepatitis Complicated by Type 2 Diabetes Mellitus: An Open-Label, Randomized, Parallel-Group Study

INTRODUCTION

Untreated nonalcoholic fatty liver may progress to nonalcoholic steatohepatitis (NASH) and cirrhosis and induce hepatocellular carcinoma and liver failure. Type 2 diabetes mellitus (T2DM), often complicated with nonalcoholic fatty liver disease (NAFLD), is a driver of NAFLD progression. Thus, efficacious treatment strategies for patients with coexisting NAFLD and T2DM are important for preventing NAFLD progression. Although previous studies have demonstrated that either sodium-glucose transporter 2 inhibitors (SGLT2is) or glucagon-like peptide 1 receptor agonists (GLP-1 RAs) benefit NASH patients with T2DM, the rate of NASH resolution has not sufficiently improved. Therefore, we developed a protocol for a randomized controlled trial to examine whether the addition of an SGLT2i to the treatment regimen of patients receving a GLP-1 RA (combination therapy), within the therapeutic dose range for T2DM, increases the rate of NASH resolution in patients with coexisting NASH and T2DM.

METHODS

This open-label, randomized, parallel-group study commenced in June 2021, will conclude recruitment in May 2023, and will end by March 2025. Sixty patients with NASH complicated by T2DM are enrolled at the Ehime University Hospital in Toon, Japan. Participants will be randomized into: (1) an intervention group receiving combination therapy with the SGLT2i luseogliflozin 2.5 mg, once daily (Taisho Pharmaceutical, Tokyo, Japan) and the GLP-1 RA semaglutide 0.5 mg, once per week (Novonordisk, Copenhagen, Denmark); and (2) a control group receiving monotherapy with the GLP-1 analog semaglutide. The primary endpoints, which will be ascertained by liver biopsy, are: (1) NASH resolution rate from baseline without worsening of liver fibrosis after 52 weeks of intervention; (2) rate of improvement from baseline of at least 1 point in the NAFLD activity score without worsening of liver fibrosis after 52 weeks of intervention; and (3) rate of improvement from baseline of at least one fibrosis stage without worsening of NASH after 52 weeks of intervention.

TRIAL REGISTRATION

University Hospital Medical Information Network Clinical Trial Registry (UMIN-CTR) number: UMIN000045003. Japan Registry of Clinical Trials registration number: jRCTs061210009.

Association of metabolic dysfunction-associated fatty liver disease with kidney disease

Non-alcoholic fatty liver disease (NAFLD) is characterized by the accumulation of fat in more than 5% of hepatocytes in the absence of excessive alcohol consumption and other secondary causes of hepatic steatosis. In 2020, the more inclusive term metabolic (dysfunction)-associated fatty liver disease (MAFLD) - defined by broader diagnostic criteria - was proposed to replace the term NAFLD. The new terminology and revised definition better emphasize the pathogenic role of metabolic dysfunction and uses a set of definitive, inclusive criteria for diagnosis. Diagnosis of MAFLD is based on evidence of hepatic steatosis (as assessed by liver biopsy, imaging techniques or blood biomarkers and scores) in persons who are overweight or obese and have type 2 diabetes mellitus or metabolic dysregulation, regardless of the coexistence of other liver diseases or excessive alcohol consumption. The known association between NAFLD and chronic kidney disease (CKD) and our understanding that CKD can occur as a consequence of metabolic dysfunction suggests that individuals with MAFLD - who by definition have fatty liver and metabolic comorbidities - are at increased risk of CKD. In this Perspective article, we discuss the clinical associations between MAFLD and CKD, the pathophysiological mechanisms by which MAFLD may increase the risk of CKD and the potential drug treatments that may benefit both conditions.

Effect of combined farnesoid X receptor agonist and angiotensin II type 1 receptor blocker on ongoing hepatic fibrosis

OBJECTIVE

Nonalcoholic steatohepatitis (NASH) is difficult to diagnose in patients with no symptoms. We aimed to investigate the combined effect of farnesoid X receptor (FXR) agonist, obeticholic acid (OCA), and angiotensin II type 1 receptor blocker (ARB: losartan) on an ongoing hepatic fibrosis in a NASH rat model.

METHODS

Fischer 344 rats were fed with choline-deficient L-amino-acid-defined (CDAA) diet for 16 weeks. After 8-week administration of CDAA diet, OCA, losartan, or a combination of these drugs was administered at a dose of 30 mg/kg/day for 8 weeks by oral gavage. The in vivo and in vitro effects of OCA + losartan and liver fibrosis progression, lipopolysaccharide (LPS), Toll-like receptor 4 (TLR4) regulatory cascade, and gut barrier function were evaluated.

RESULTS

OCA + losartan alleviated hepatic fibrosis progression by suppressing α-SMA expression. It inhibited the proliferation of activated hepatic stellate cell (Ac-HSC) and mRNA expression of hepatic transforming growth factor-β1 (TGF-β1), TLR4, and tissue inhibitor of metalloproteinase-1 (TIMP-1) and decreased the hydroxyproline levels. OCA increased the hepatic matrix metalloproteinase-2 (MMP-2) mRNA expression. OCA decreased the mRNA expression of hepatic LPS-binding protein and intestinal permeability by ameliorating the disruption of CDAA diet-induced zonula occludens-1. Losartan directly inhibited the proliferation of Ac-HSC. The in vitro suppressive effects of OCA + losartan on the mRNA expressions of TGF-β1 and α1(I)-procollagen, TLR4, and TIMP-1 in Ac-HSCs were almost in parallel.

CONCLUSIONS

OCA + losartan suppressed the ongoing hepatic fibrosis by attenuating gut barrier dysfunction and suppressing Ac-HSC proliferation. Combined therapy may be a promising novel approach for NASH with fibrosis.

Non-alcoholic Fatty Liver Disease and Steatohepatitis: Risk Factors and Pathophysiology

Non-alcoholic fatty liver disease (NAFLD) and its progressive subtype non-alcoholic steatohepatitis (NASH) are the most prevalent liver diseases, often leading to hepatocellular carcinoma (HCC). This review aims to describe the present knowledge of the risk factors responsible for the development of NAFLD and NASH. I performed a literature review identifying studies focusing on the complex pathogenic pathway and risk factors of NAFLD and steatohepatitis. The relationship between NAFLD and metabolic syndrome is well established and widely recognized. Obesity, dyslipidemia, type 2 diabetes, hypertension, and insulin resistance are the most common risk factors associated with NAFLD. Among the components of metabolic syndrome, current evidence strongly suggests obesity and type 2 diabetes as risk factors of NASH and HCC. However, other elements, namely gender divergences, ethnicity, genetic factors, participation of innate immune system, oxidative stress, apoptotic pathways, and adipocytokines, take a leading role in the onset and promotion of NAFLD. Pathophysiological mechanisms that are responsible for NAFLD development and subsequent progression to NASH are insulin resistance and hyperinsulinemia, oxidative stress, hepatic stellate cell (HSC) activation, cytokine/adipokine signaling pathways, and genetic and environmental factors. Major pathophysiological findings of NAFLD are dysfunction of adipose tissue through the enhanced flow of free fatty acids (FFAs) and release of adipokines, and altered gut microbiome that generate proinflammatory signals and cause NASH progression. Understanding the pathophysiology and risk factors of NAFLD and NASH; this review could provide insight into the development of therapeutic strategies and useful diagnostic tools.

Rodent models and metabolomics in non-alcoholic fatty liver disease: What can we learn?

Non-alcoholic fatty liver disease (NAFLD) prevalence has increased drastically in recent decades, affecting up to 25% of the world’s population. NAFLD is a spectrum of different diseases that starts with asymptomatic steatosis and continues with development of an inflammatory response called steatohepatitis, which can progress to fibrosis. Several molecular and metabolic changes are required for the hepatocyte to finally vary its function; hence a “multiple hit” hypothesis seems a more accurate proposal. Previous studies and current knowledge suggest that in most cases, NAFLD initiates and progresses through most of nine hallmarks of the disease, although the triggers and mechanisms for these can vary widely. The use of animal models remains crucial for understanding the disease and for developing tools based on biological knowledge. Among certain requirements to be met, a good model must imitate certain aspects of the human NAFLD disorder, be reliable and reproducible, have low mortality, and be compatible with a simple and feasible method. Metabolism studies in these models provides a direct reflection of the workings of the cell and may be a useful approach to better understand the initiation and progression of the disease. Metabolomics seems a valid tool for studying metabolic pathways and crosstalk between organs affected in animal models of NAFLD and for the discovery and validation of relevant biomarkers with biological understanding. In this review, we provide a brief introduction to NAFLD hallmarks, the five groups of animal models available for studying NAFLD and the potential role of metabolomics in the study of experimental NAFLD.

Formyl peptide receptor 2 determines sex-specific differences in the progression of nonalcoholic fatty liver disease and steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is an important health concern worldwide and progresses into nonalcoholic steatohepatitis (NASH). Although prevalence and severity of NAFLD/NASH are higher in men than premenopausal women, it remains unclear how sex affects NAFLD/NASH pathophysiology. Formyl peptide receptor 2 (FPR2) modulates inflammatory responses in several organs; however, its role in the liver is unknown. Here we show that FPR2 mediates sex-specific responses to diet-induced NAFLD/NASH. NASH-like liver injury was induced in both sexes during choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) feeding, but compared with females, male mice had more severe hepatic damage. Fpr2 was more highly expressed in hepatocytes and healthy livers from females than males, and FPR2 deletion exacerbated liver damage in CDAHFD-fed female mice. Estradiol induced Fpr2 expression, which protected hepatocytes and the liver from damage. In conclusion, our results demonstrate that FPR2 mediates sex-specific responses to diet-induced NAFLD/NASH, suggesting a novel therapeutic target for NAFLD/NASH.

Hepatotoxicity-Related Adverse Effects of Proton Pump Inhibitors: A Cross-Sectional Study of Signal Mining and Analysis of the FDA Adverse Event Report System Database

Background and Objectives: Mounting evidence demonstrates that proton pump inhibitors (PPIs) are associated with a number of adverse effects. However, the literatures about hepatotoxicity-related adverse effects (HRAEs) of PPIs are mostly case reports and a few clinical studies.

Methods: We evaluated the association between PPIs and HAREs using the reporting odd ratio (ROR) for mining the adverse event report signals in the FDA Adverse Event Reporting System (FAERS) database.

Results: There were 23,825 reports of PPIs as primary suspect drug or second suspect drug, of which 3,253 reports were HRAEs. The top five HRAE signals caused by PPIs were hepatitis cholestatic, cholestasis, fulminant hepatitis, subacute hepatic failure, and acute hepatitis. We also summarized the signals of the HRAEs caused by each PPI. The simultaneous signals were cholestasis and hepatitis cholestatic. For the cholestasis signal, esomeprazole showed an ROR of 21.556 (95% CI 17.592–26.413); pantoprazole showed the highest ROR of 22.611 (95% CI 17.794–28.733) in the hepatic cholestatic signal; lansoprazole was the only PPI with expression in the coma hepatic signal, with an ROR of 10.424 (95% CI 3.340–32.532). By analyzing the reports of pantoprazole-induced hepatic encephalopathy, we found that patients aged over 65 years and males reported the highest rate. And from the combination of drugs and indications of drugs, no significant results were obtained.

Conclusions: The RORs of signals of “cholestasis” were generally higher than those of “hepatocellular injury.” And the signals about “cholestasis” in HRAE caused by PPIs are more reported.

Evidence-based clinical practice guidelines for nonalcoholic fatty liver disease/nonalcoholic steatohepatitis 2020

Nonalcoholic fatty liver disease (NAFLD) has become a serious public health issue not only in Western countries but also in Japan. Within the wide spectrum of NAFLD, nonalcoholic steatohepatitis (NASH) is a progressive form of disease that often develops into liver cirrhosis and increases the risk of hepatocellular carcinoma (HCC). While a definite diagnosis of NASH requires liver biopsy to confirm the presence of hepatocyte ballooning, hepatic fibrosis is the most important prognostic factor in NAFLD. With so many NAFLD patients, it is essential to have an effective screening method for NAFLD with hepatic fibrosis. As HCC with non-viral liver disease has increased markedly in Japan, effective screening and surveillance of HCC are also urgently needed. The most common death etiology in NAFLD patients is cardiovascular disease (CVD) event. Gastroenterologists must, therefore, pay close attention to CVD when examining NAFLD patients. In the updated guidelines, we propose screening and follow-up methods for hepatic fibrosis, HCC, and CVD in NAFLD patients. Several drug trials are ongoing for NAFLD/NASH therapy, however, there is currently no specific drug therapy for NAFLD/NASH. In addition to vitamin E and thiazolidinedione derivatives, recent trials have focused on sodium glucose co-transporter 2 (SGLT2) inhibitors and glucagon-like peptide-1 (GLP-1) analogues, and effective therapies are expected to be developed. These practical guidelines for NAFLD/NASH were established by the Japanese Society of Gastroenterology in conjunction with the Japan Society of Hepatology. Clinical evidence reported internationally between 1983 and October 2018 was collected, and each clinical and background question was evaluated using the Grades of Recommendation Assessment, Development and Evaluation (GRADE) system. This English summary provides the core essentials of these clinical practice guidelines, which include the definition and concept, screening systems for hepatic fibrosis, HCC and CVD, and current therapies for NAFLD/NASH in Japan.

Evidence-based clinical practice guidelines for nonalcoholic fatty liver disease/nonalcoholic steatohepatitis 2020

Nonalcoholic fatty liver disease (NAFLD) has become a serious public health issue not only in Western countries but also in Japan. Within the wide spectrum of NAFLD, nonalcoholic steatohepatitis (NASH) is a progressive form of disease that often develops into liver cirrhosis and increases the risk of hepatocellular carcinoma (HCC). While a definite diagnosis of NASH requires liver biopsy to confirm the presence of hepatocyte ballooning, hepatic fibrosis is the most important prognostic factor in NAFLD. With so many NAFLD patients, it is essential to have an effective screening method for NAFLD with hepatic fibrosis. As HCC with non-viral liver disease has increased markedly in Japan, effective screening and surveillance of HCC are also urgently needed. The most common death etiology in NAFLD patients is cardiovascular disease event. Gastroenterologists must, therefore, pay close attention to CVD when examining NAFLD patients. In the updated guidelines, we propose screening and follow-up methods for hepatic fibrosis, HCC, and CVD in NAFLD patients. Several drug trials are ongoing for NAFLD/NASH therapy, however, there is currently no specific drug therapy for NAFLD/NASH. In addition to vitamin E and thiazolidinedione derivatives, recent trials have focused on sodium glucose co-transporter 2 (SGLT2) inhibitors and glucagon-like peptide-1 (GLP-1) analogues, and effective therapies are expected to be developed. These practical guidelines for NAFLD/NASH were established by the Japanese Society of Gastroenterology in conjunction with the Japan Society of Hepatology. Clinical evidence reported internationally between 1983 and October 2018 was collected, and each clinical and background question was evaluated using the Grades of Recommendation Assessment, Development and Evaluation (GRADE) system. This English summary pro- vides the core essentials of these clinical practice guidelines, which include the definition and concept, screening systems for hepatic fibrosis, HCC and CVD, and current therapies for NAFLD/NASH in Japan.

Burden of non-alcoholic fatty liver disease in Asia, the Middle East and North Africa: Data from Global Burden of Disease 2009-2019

BACKGROUND & AIM

Non-alcoholic fatty liver disease (NAFLD) has become a major cause of chronic liver disease (CLD) worldwide. Our aim was to assess the burden of liver complications (LC, cirrhosis and liver cancer) related to NAFLD (LC-NAFLD) between 2009-2019 in Asia and the Middle East and North Africa (MENA) region.

METHODS

We used Global Burden of Disease data to assess incidence, mortality, and disability-adjusted life years (DALYs) for LC-NAFLD from Asia and the MENA region. Annual % change (APC) in rates were computed using a joinpoint regression model. Associations of LC-NAFLD with low physical activity, diet and metabolic risks were determined by partial Spearman correlation coefficients (ρ).

RESULTS

Globally in 2019, there were 170,000 incident cases of LC-NAFLD, accounting for 6.6% of LC incident cases from all CLDs. There were 168,969 deaths related to LC-NAFLD, accounting for 8.6% of LC deaths from all CLDs. Asia accounted for 48.3% of the global incidence of LC-NAFLD and for 46.2% of deaths attributable to LC-NAFLD, while MENA accounted for 8.9% and 8.6%, respectively. There were 2.08 million DALYs in Asia and 340,000 DALYs in MENA. From 2009 to 2019, regions in Asia and MENA experienced a rise in DALYs attributable to LC-NAFLD (compared to LC from other CLDs), ranging from South Asia (APC = +2.12% vs. -0.94%) to high-income Asia Pacific (APC = -0.07%, p = 0.646 vs. -0.97%). In Asia, NAFLD-related DALYs were significantly correlated with dietary risks (95% CI 0.280-0.763, p = 0.004), metabolic risks (0.341-0.790, p <0.001) and tobacco use (0.134-0.691, p = 0.007). In MENA, low physical activity (0.557-0.918, p <0.001), metabolic risks (0.432-0.888, p = 0.001), and dietary risks (0.315-0.855, p = 0.001) correlated with DALYs.

CONCLUSIONS

NAFLD is posing a substantial burden in Asia and MENA. About half of the global burden of LC-NAFLD is accounted for by these regions.

LAY SUMMARY

Non-alcoholic fatty liver disease (NAFLD) has emerged as one of the most common causes of chronic liver disease worldwide. We used Global Burden of Disease data to assess the incidence, mortality, and disability-adjusted life years attributable to NAFLD-related liver complications in Asia, the Middle East and North Africa. NAFLD is poised to contribute to a substantial liver disease burden in these regions. Regional and global policies are needed to address the increasing burden of complications of NAFLD.

[Development of liver organoids from NASH model mice and their application to drug discovery]

Nonalcoholic steatohepatitis (NASH) is one of the most common causes of chronic liver disease, with the increased prevalence of obesity, type 2 diabetes, and metabolic disorders in recent years. As the disease progresses, it leads to hepatic fibrosis, which may progress to hepatocellular carcinoma, but there is still no cure for severe hepatic fibrosis. Currently, in order to develop drugs for the treatment of NASH, the effects of candidate drugs are evaluated by a long-term administration to mice and rats that are fed a high-fat or methionine-deficient diet to reproduce the pathology of fatty liver and liver fibrosis. Since drug development using these experimental animals is time-consuming and costly, in vitro models that reproduce the pathology of NASH have recently been developing. In this review, we will outline the current issues in the diagnosis and treatment of NASH, and introduce our research for the discovery of early diagnostic markers and the development of new therapeutic agents using liver organoid cultures derived from mouse models of NASH.

Impact of continuous positive airway pressure therapy for nonalcoholic fatty liver disease in patients with obstructive sleep apnea

BACKGROUND

Obstructive sleep apnea (OSA) has been suggested as an independent risk factor for nonalcoholic fatty liver disease (NAFLD), and continuous positive airway pressure (CPAP) is the first-line therapy for OSA.

AIM

To clarify the efficacy of effective CPAP therapy on NAFLD of OSA patients by serum markers and transient elastography (TE) using FibroScan® (Echosens, Paris, France).

METHODS

We prospectively enrolled 123 consecutive patients with OSA who met the indications for CPAP. Liver fibrosis and steatosis were assessed using TE. Before and after 6 mo of CPAP therapy, serum markers and TE were assessed for all patients. The mean usage rate of CPAP therapy for 6 mo was arbitrarily calculated in each patient and expressed as "mean compliance index" (m-CI).

RESULTS

In 50 OSA patients with NAFLD, both aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were significantly decreased after 6 mo of CPAP therapy. Univariate analysis showed that decreased body weight (BW), decreased body mass index (BMI), decreased AST level, decreased hemoglobin A1c, and high m-CI were significantly related with improved ALT level. In multivariate regression model adjusted for quantities of BW change during 6 mo of CPAP therapy, high m-CI tended to improve ALT level (P = 0.051). All 17 OSA patients with NAFLD, high m-CI and no BMI changes showed significant improvements in AST and ALT levels. Meanwhile, no significant changes in TE data or serum fibrosis markers were seen.

CONCLUSION

Some NAFLD could be associated with chronic intermittent hypoxia due to OSA independent of BW changes. In those cases, adequate reoxygenation from effective CPAP therapy may improve NAFLD.

Systematic review on the prevalence of nonalcoholic fatty liver disease in South Korea

AIMS

We aimed to conduct a systematic review and a meta-analysis to estimate NAFLD prevalence and its change in Korea.

METHODS

We searched the literature involving NAFLD prevalence in Korea in PubMed, RISS, and KMBASE from inception to June 2017. Studies with subjects with certain disorders, population limitations, or subjects who consume alcohol were excluded. Analysis was stratified by publication year, age, gender, severity, body mass index (BMI), and diagnostic technique. Random-effects models were used to provide point estimates (95% confidence interval) of prevalence with subgroup analysis to account for heterogeneity.

RESULTS

A total of 61 studies (837,897 participants) were included. The overall NAFLD prevalence in Korea was 30.3% (men: 41.1%, women: 20.3%), with a slight increase from 29.0% to 31.0% over an approximately 10-year period. BMI significantly affected NAFLD prevalence (≤ or > 25 kg/m2, 12.3% vs. 41.7%, p < 0.001), while women were significantly affected by aging (< or ≥ 50 years, 17.0% vs. 25.8%, p < 0.01). The prevalence of steatosis by severity was 22.6% for mild, 9.8% for moderate to severe and 2.2% for nonalcoholic steatohepatitis (NASH), with different patterns by gender.

CONCLUSION

The current study is the first systematic analysis on NAFLD prevalence in Korea and found a change in NAFLD prevalence during the recent decade.

The association between non-alcoholic fatty liver disease (with or without metabolic syndrome) and extrahepatic cancer development

BACKGROUND AND AIM

This study was designed to determine whether non-alcoholic fatty liver disease (NAFLD), with or without metabolic syndrome (MetS), is a risk factor for cancer development.

METHODS

We conducted a retrospective longitudinal study at the Center for Preventive Medicine, St. Luke's International Hospital. Among all participants who underwent a health checkup between 2005 and 2019, cancer development tendencies were compared between those who were diagnosed with NAFLD and those who were not. Further evaluation was conducted among NAFLD-diagnosed participants with versus without MetS in the same manner. Those with a history of a specific liver disease, any type of cancer, or alcohol consumption in any amount at the time of the initial visit were excluded from the study.

RESULTS

Data were collected from 30 172 participants who underwent health checkups, among whom 4394 (14.6%) had NAFLD. Over the 14-year follow-up period, 2086 participants (6.9%) developed cancer. Participants with NAFLD had a higher incidence of digestive organ neoplasms (odds ratio [OR]: 1.34, 95% confidence interval [CI]: 1.07-1.67), especially in the stomach (OR: 1.40, 95% CI: 1.02-1.94) and small intestine (OR: 2.80, 95% CI: 0.87-8.96), than did those without NAFLD. Participants with NAFLD and MetS had significantly lower rates of neoplasms in respiratory and intrathoracic organs (OR: 0.35 95% CI: 0.14-0.88) and male genital organs (OR: 0.46 95% CI: 0.24-0.87) than did individuals without NAFLD.

CONCLUSIONS

Non-alcoholic fatty liver disease is associated with the development of gastrointestinal malignancies, while MetS is a negative risk factor for lung and prostate cancer.

The Association between Decreased Kidney Function and FIB-4 Index Value, as Indirect Liver Fibrosis Indicator, in Middle-Aged and Older Subjects

Liver fibrosis might be linked to the prevalence of chronic kidney disease (CKD). However, there is little information about the association between liver fibrosis and decreased kidney function in middle-aged and older subjects. We aimed to evaluate the influence of liver fibrosis on the incidence or prevalence of CKD stage 3–5 in a retrospective cross-sectional study (Study 1, n = 806) and a 6-year longitudinal study (Study 2, n = 380) of middle-aged and older subjects. We evaluated liver fibrosis using the Fibrosis-4 (FIB-4) index and kidney function using the estimated glomerular filtration rate (eGFR) of all subjects. All subjects were divided into four groups on the basis of their FIB-4 score quartiles (low to high). In the Jonckheere–Terpstra trend test of Study 1, the eGFR decreased significantly from the lowest group to the highest group (p < 0.001). The Kaplan–Meier survival curve in Study 2 showed that the cumulative prevalence of CKD stage 3–5 was higher in the third quartile than the other quartiles. Our results suggest that liver fibrosis could be a useful indicator for the prevalence of CKD, even within a relatively healthy population, although liver fibrosis was not an independent risk factor.