FXR activation remodels hepatic and intestinal transcriptional landscapes in metabolic dysfunction-associated steatohepatitis.

The escalating obesity epidemic and aging population have propelled metabolic dysfunction-associated steatohepatitis (MASH) to the forefront of public health concerns. The activation of FXR shows promise to combat MASH and its detrimental consequences. However, the specific alterations within the MASH-related transcriptional network remain elusive, hindering the development of more precise and effective therapeutic strategies. Through a comprehensive analysis of liver RNA-seq data from human and mouse MASH samples, we identified central perturbations within the MASH-associated transcriptional network, including disrupted cellular metabolism and mitochondrial function, decreased tissue repair capability, and increased inflammation and fibrosis. By employing integrated transcriptome profiling of diverse FXR agonists-treated mice, FXR liver-specific knockout mice, and open-source human datasets, we determined that hepatic FXR activation effectively ameliorated MASH by reversing the dysregulated metabolic and inflammatory networks implicated in MASH pathogenesis. This mitigation encompassed resolving fibrosis and reducing immune infiltration. By understanding the core regulatory network of FXR, which is directly correlated with disease severity and treatment response, we identified approximately one-third of the patients who could potentially benefit from FXR agonist therapy. A similar analysis involving intestinal RNA-seq data from FXR agonists-treated mice and FXR intestine-specific knockout mice revealed that intestinal FXR activation attenuates intestinal inflammation, and has promise in attenuating hepatic inflammation and fibrosis. Collectively, our study uncovers the intricate pathophysiological features of MASH at a transcriptional level and highlights the complex interplay between FXR activation and both MASH progression and regression. These findings contribute to precise drug development, utilization, and efficacy evaluation, ultimately aiming to improve patient outcomes.

The burden and sexual dimorphism with nonalcoholic fatty liver disease in Asian children: A systematic review and meta-analysis.

BACKGROUND: Despite substantial attention paid to the epidemic of nonalcoholic fatty liver disease (NAFLD) in adults, data on the burden and sexual dimorphism of NAFLD in Asian children have not yet been synthesized. METHODS: We conducted a literature search of 735 references up to April 2021. Pooled analyses, stratified analyses and meta-regression were all performed. RESULTS: Thirty-three study populations were finally included. Nine of them comprising 20 595 children showed an overall NAFLD prevalence of 5.53% (95% CI 3.46%-8.72%), in which, 36.64% (95% CI, 27.99%-46.26%) NAFLD subjects had elevated levels of ALT. The prevalence rate of NAFLD increased about 1.6-fold from 2004 to 2010 to the last decade. Male predominant trends were observed in paediatric NAFLD (boys: 8.18%, 95% CI 4.93%-13.26%; girls: 3.60%, 95% CI 1.60%-7.87%). Moreover, meta-analysis showed that after 10 years of age, boys were more prone to have NAFLD than girls (OR = 1.75; P = .0012). In addition, the pooled prevalence of NAFLD increased sequentially in normal-weight (1.49%, 95% CI 0.88%-2.51%, n = 2610), overweight (16.72%, 95% CI 7.07%-34.65%, n = 1265) and obese children (50.13%, 95% CI 41.99%-58.27%, n = 6434 individuals). After full covariate adjustment, the multivariate meta-regression also showed that boy percentage (P = .0396) and body mass index (P < .0001) were positively correlated with prevalent NAFLD. CONCLUSIONS: In Asia, paediatric NAFLD is becoming prevalent over the recent decades, particularly among obese children and boys after 10 years old. The hormonal and chromosomal origins of paediatric NAFLD dimorphism need further investigation.

Influence of weight management on the prognosis of steatohepatitis in chronic hepatitis B patients during antiviral treatment.

BACKGROUND: Although concomitant nonalcoholic steatohepatitis (NASH) is common in chronic hepatitis B (CHB), the impact of viral factors on NASH and the outcome of CHB patients concomitant with NASH remain unclear. We aimed to investigate the outcomes of NASH in CHB patients receiving antiviral treatment. METHODS: In the post-hoc analysis of a multicenter trial, naïve CHB patients receiving 72-week entecavir treatment were enrolled. We evaluated the biochemical, viral and histopathological responses of these patients. The histopathological features of NASH were also evaluated, using paired liver biopsies at baseline and week 72. RESULTS: A total of 1000 CHB patients were finally enrolled for analysis, with 18.2% of whom fulfilling the criteria of NASH. A total of 727 patients completed entecavir antiviral treatment and received the second biopsy. Serum HBeAg loss, HBeAg seroconversion and HBV-DNA undetectable rates were similar between patients with or without NASH (P > 0.05). Among patients with NASH, the hepatic steatosis, ballooning, lobular inflammation scores and fibrosis stages all improved during follow-up (all P < 0.001), 46% (63/136) achieved NASH resolution. Patients with baseline body mass index (BMI) ≥ 23 kg/m2 (Asian criteria) [odds ratio (OR): 0.414; 95% confidence interval (95% CI): 0.190-0.899; P = 0.012] and weight gain (OR: 0.187; 95% CI: 0.050-0.693; P = 0.026) were less likely to have NASH resolution. Among patients without NASH at baseline, 22 (3.7%) developed NASH. Baseline BMI ≥ 23 kg/m2 (OR: 12.506; 95% CI: 2.813-55.606; P = 0.001) and weight gain (OR: 5.126; 95% CI: 1.674-15.694; P = 0.005) were predictors of incident NASH. CONCLUSIONS: Lower BMI and weight reduction but not virologic factors determine NASH resolution in CHB. The value of weight management in CHB patients during antiviral treatment deserves further evaluation.

Transcriptomic Landscape Analysis Reveals a Persistent DNA Damage Response in Metabolic Dysfunction-associated Steatohepatitis Post-dietary Intervention.

Background and Aims: Metabolic dysfunction-associated steatotic liver disease (MASLD) and its more advanced form, metabolic dysfunction-associated steatohepatitis, have emerged as the most prevalent liver diseases worldwide. Currently, lifestyle modification is the foremost guideline-recommended management strategy for MASLD. However, it remains unclear which detrimental signals persist in MASLD even after disease remission. Thus, we aimed to examine the persistent changes in liver transcriptomic profiles following this reversal. Methods: Male C57BL/6J mice were divided into three groups: Western diet (WD) feeding, chow diet (CD) feeding, or diet reversal from WD to CD. After 16 weeks of feeding, RNA sequencing was performed on the mice's livers to identify persistent alterations characteristic of MASLD. Additionally, RNA sequencing databases containing high-fat diet-fed P53-knockout mice and human MASLD samples were utilized. Results: WD-induced MASLD triggered persistent activation of the DNA damage response (DDR) and its primary transcription factor, P53, long after the resolution of the hepatic phenotype through dietary reversal. Elevated levels of P53 might promote apoptosis, thereby exacerbating metabolic dysfunction-associated steatohepatitis, as they strongly correlated with hepatocyte ballooning, an indicator of apoptosis activation. Moreover, P53 knockout in mice led to downregulated expression of apoptosis signaling in the liver. Mechanistically, P53 may regulate apoptosis by transcriptionally activating the expression of apoptosis-enhancing nuclease (AEN). Consistently, P53, AEN, and the apoptosis process all exhibited persistently elevated expression and showed a strong inter-correlation in the liver following dietary reversal. Conclusions: The liver demonstrated upregulation of DDR signaling and the P53-AEN-apoptosis axis both during and after exposure to WD. Our findings provide new insights into the mechanisms of MASLD relapse, highlighting DDR signaling as a promising target to prevent MASLD recurrence.

Association of maternal obesity and gestational diabetes mellitus with overweight/obesity and fatty liver risk in offspring.

BACKGROUND: Childhood obesity and fatty liver are associated with adverse outcomes such as diabetes, metabolic syndrome, and cardiovascular diseases in adulthood. It is very important to identify relevant risk factors and intervene as early as possible. At present, the relationship between maternal and offspring metabolic factors is conflicting. AIM: To estimate the association of maternal obesity and gestational diabetes mellitus (GDM) with overweight/obesity and fatty liver risk in offspring at 8 years of age. METHODS: The prospective study included mothers who all had a 75-g oral glucose tolerance test at 24-28 wk of gestation and whose offspring completed follow-up at 8 years of age. Offspring birth weight, sex, height, weight, and body mass index (BMI) were measured and calculated. FibroScan-502 examination with an M probe (Echosens, Paris, France) was prospectively conducted in offspring aged 8 years from the Shanghai Prenatal Cohort Study. RESULTS: A total of 430 mother-child pairs were included in the analysis. A total of 62 (14.2%) mothers were classified as obese, and 48 (11.1%) were classified as having GDM. The mean age of the offspring at follow-up was 8 years old. Thirty-seven (8.6%) offspring were overweight, 14 (3.3%) had obesity, and 60 (14.0%) had fatty liver. The prevalence of overweight, obesity and fatty liver in offspring increased significantly across maternal BMI quartiles (all P < 0.05). Among offspring of mothers with GDM, 12 (25.0%) were overweight, 4 (8.3%) were obese, and 12 (25.0%) had fatty liver vs. 25 (6.5%), 10 (2.6%) and 48 (12.6%), respectively, for offspring of mothers without GDM (all P < 0.05). In multiple logistic regression, after adjustment for variables, the OR for fatty liver in offspring was 8.26 (95%CI: 2.38-28.75) for maternal obesity and GDM. CONCLUSION: This study showed that maternal obesity can increase the odds of overweight/obesity and fatty liver in offspring, and GDM status also increases the odds of overweight/obesity in offspring. Weight management and glycemic control before and during pregnancy need to be highlighted in primary prevention of pediatric obesity and fatty liver.

Premorbid Steatohepatitis Increases the Seriousness of Dextran Sulfate Sodium-induced Ulcerative Colitis in Mice.

Background and Aims: The concurrence of nonalcoholic steatohepatitis (NASH) and ulcerative colitis (UC) is increasingly seen in clinical practice, but the underlying mechanisms remain unclear. This study aimed to develop a mouse model of the phenomenon by combining high-fat high-cholesterol diet (HFHCD)-induced NASH and dextran sulfate sodium (DSS)-induced UC, that would support mechanistic studies. Methods: Male C57BL/6 mice were randomly assigned to two groups receiving either a chow diet or HFHCD for 12 weeks of NASH modeling. The mice were the divided into four subgroups for UC modeling: (1) A control group given a chow diet with normal drinking water; (2) A colitis group given chow diet with 2% DSS in drinking water; (3) A steatohepatitis group given HFHCD with normal drinking water; and (4) A steatohepatitis + colitis group given HFHCD with 2% DSS in drinking water. Results: NASH plus UC had high mortality (58.3%). Neither NASH nor UC alone were fatal. Although DSS-induced colitis did not exacerbate histological liver injury in HFHCD-fed mice, premorbid NASH significantly increased UC-related gut injury compared with UC alone. It was characterized by a significantly shorter colon, more colonic congestion, and a higher histopathological score (p<0.05). Inflammatory (tumor necrosis factor-alpha, interleukin 1 beta, C-C motif chemokine ligand 2, and nuclear factor kappa B) and apoptotic (Bcl2, Bad, Bim, and Bax) signaling pathways were significantly altered in distal colon tissues collected from mice with steatohepatitis + colitis compared with the other experimental groups. Conclusions: Premorbid steatohepatitis significantly aggravated DSS-induced colitis and brought about a lethal phenotype. Potential links between NASH and UC pathogeneses can be investigated using this model.

Efficacy of Intragastric Balloons in the Markers of Metabolic Dysfunction-associated Fatty Liver Disease: Results from Meta-analyses.

BACKGROUND AND AIMS: Nonalcoholic fatty liver disease, now renamed metabolic dysfunction-associated fatty liver disease (MAFLD), is common in obese patients. Intragastric balloon (IGB), an obesity management tool with low complication risk, might be used in MAFLD treatment but there is still unexplained heterogeneity in results across studies. METHODS: We conducted a systematic search of 152 citations published up to September 2020. Meta-analyses, stratified analyses, and meta-regression were performed to evaluate the efficacy of IGB on homeostasis model assessment of insulin resistance (HOMA-IR), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transpeptidase (GGT), and to identify patients most appropriate for IGB therapy. RESULTS: Thirteen observational studies and one randomized controlled trial met the inclusion criteria (624 participants in total). In the overall estimate, IGB therapy significantly improved the serum markers change from baseline to follow-up [HOMA-IR: 1.56, 95% confidence interval (CI)=1.16-1.95; ALT: 11.53 U/L, 95% CI=7.10-15.96; AST: 6.79 U/L, 95% CI=1.69-11.90; GGT: 10.54 U/L, 95% CI=6.32-14.75]. In the stratified analysis, there were trends among participants with advanced age having less change in HOMA-IR (1.07 vs. 1.82). The improvement of insulin resistance and liver biochemistries with swallowable IGB therapy was no worse than that with endoscopic IGB. Multivariate meta-regression analyses showed that greater HOMA-IR loss was predicted by younger age (p=0.0107). Furthermore, effectiveness on ALT and GGT was predicted by basal ALT (p=0.0004) and GGT (p=0.0026), respectively. CONCLUSIONS: IGB is effective among the serum markers of MAFLD. Younger patients had a greater decrease of HOMA-IR after IGB therapy.

The presence of NAFLD in nonobese subjects increased the risk of metabolic abnormalities than obese subjects without NAFLD: a population-based cross-sectional study.

BACKGROUND: With lifestyle modification and over-nutrition, the prevalence of nonalcoholic fatty liver disease (NAFLD) has been increasing annually. Here we aimed to assess the updated prevalence of NAFLD, and to evaluate the association of NAFLD with metabolic abnormalities according to gender, body mass index and age. METHODS: A population-based cross-sectional study was conducted in Shanghai from December 2016 to July 2017. With a three-stage stratified sampling strategy, 3,717 eligible participants were enrolled for the analysis. RESULTS: In total, 1,217 subjects (32.7%) had NAFLD. Among them, 400 (16.3%) of the nonobese and 817 (65.0%) of the obese subjects had NAFLD. The prevalence of NAFLD was increased according to the quartiles of age and waist circumference (WC) in the nonobese subjects. Females with nonobese NAFLD had 1.6-, 2.6-, 2.0-, 2.3- and 3.3-fold higher risks for metabolic syndrome, diabetes mellitus, hyperglycemia, hypertriglycerdemia (high TG) and low high-density lipoprotein cholesterol than obese subjects without NAFLD, respectively. Males had comparable metabolic profiles in both groups, except for a 2.0-fold higher risk of high TG in nonobese NAFLD subjects compared with obese subjects without NAFLD. More impressively, the homeostasis metabolic assessment insulin resistance index was comparable between the two groups. CONCLUSIONS: The increase of age and WC had significant impact on the risk of NAFLD in nonobese subjects. The presence of NAFLD in nonobese subjects increased the risk of metabolic diseases than obese subjects without NAFLD, especially in female.

Epidemiology of nonalcoholic fatty liver disease in non-obese populations: Meta-analytic assessment of its prevalence, genetic, metabolic, and histological profiles.

OBJECTIVE: As a subgroup of nonalcoholic fatty liver disease (NAFLD), patients with non-obese NAFLD may also have an increased risk of adverse hepatic and metabolic outcomes. We aimed to estimate the prevalence and incidence of non-obese NAFLD and to describe its clinical characteristics in this systematic review and meta-analysis. METHODS: We performed a systematic search of 1235 citations published up to Mar 2020. Meta-analyses, stratified analyses and meta-regression were all performed. RESULTS: Of the 46 studies included, 28 cross-sectional and longitudinal studies of 155 846 non-obese participants reported a pooled NAFLD prevalence of 14.5% (95% confidence interval [CI] 12.3%-17.1%). A multivariate meta-regression analysis showed the trend that the prevalence varied by their geographical location. Further stratified analyses showed that NAFLD was relatively prevalent among people aged ≥45 years (16.2%; 95% CI 10.8-23.4) and those in South America (25.7%; 95% CI 24.4-27.0). The PNPLA3 rs738409 gene polymorphism was more frequently observed in non-obese NAFLD than in both obese NAFLD and non-obese controls, while the metabolic profiles of non-obese NAFLD were less severe than those of the obese NAFLD group. Patients with non-obese NAFLD had 4.81-fold and 5.43-fold higher risk of diabetes mellitus and metabolic syndrome, respectively, than the non-obese controls. CONCLUSIONS: Non-obese NAFLD is common, particularly in South America and among people aged ≥45 years. Metabolic diseases and PNPLA3 rs738409 gene polymorphism are more frequent in the non-obese NAFLD group than in non-obese controls.

Systematic Review With Meta-analysis: Epidemiology of Nonalcoholic Fatty Liver Disease in Patients With Inflammatory Bowel Disease.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is increasingly identified in patients with inflammatory bowel disease (IBD), but there are few systematic reviews and meta-analyses of the studies of NAFLD in IBD patients. METHODS: MEDLINE, Web of Science, Cochrane Library, and Scopus were searched (until August 2018) to identify observational studies that reported the prevalence and risk factors for NAFLD in IBD patients. Pooled prevalence, odds ratios (OR), mean difference (MD), and 95% confidence intervals (95% CI) were calculated. Study quality was assessed using the modified Newcastle-Ottawa scale. RESULTS: Of the 662 citations evaluated, 19 studies (including 5620 subjects) reported the prevalence of NAFLD in IBD population and were included for the analysis. The overall pooled prevalence was 27.5% (95% CI, 20.7%-34.2%). The prevalence was higher in older patients (MD = 8.22; 95% CI, 6.22-10.22), type 2 diabetes (OR = 3.85; 95% CI, 2.49-5.95), hypertension (OR = 3.18; 95% CI, 2.36-4.28), obesity (OR = 2.79; 95% CI, 1.73-4.50), insulin resistance (OR = 6.66; 95% CI, 1.28-34.77), metabolic syndrome (OR = 4.96; 95% CI, 3.05-8.05), chronic kidney disease (OR = 4.83; 95% CI, 1.79-13.04), methotrexate use (OR = 1.76; 95% CI, 1.02-3.06), surgery for IBD (OR = 1.28; 95% CI, 1.02-1.62), and longer duration of IBD (MD = 5.60; 95% CI, 2.24-8.97). CONCLUSIONS: We found that NAFLD was not uncommon in the IBD population. Older age, metabolic risk factors, methotrexate use, prior surgery, and longer duration of IBD are predictors for the presence of NAFLD in IBD. Screening of NAFLD might be recommended among IBD patients with the aforementioned factors.