Histopathological findings of nonalcoholic fatty liver disease and nonalcoholic steatohepatitis

Dietary polysaccharides from dragon fruit pomace, a co-product of the fruit processing industry, exhibit therapeutic potential in high-fat diet-induced metabolic disorders

The increasing prevalence of metabolic disorders, often associated with high-fat diets (HFD), highlights the need for new therapeutic approaches, especially from natural sources. Dragon fruit pomace, a by-product of the fruit processing industry, is rich in polysaccharides with potential health benefits. This study investigates the effects of dragon fruit pomace-derived polysaccharides (PDPS) in alleviating HFD-induced metabolic dysfunction. Treatment with PDPS in mice fed a high-fat diet led to significant decreases in body weight increase, abdominal fat accumulation, total cholesterol, triglycerides, and low-density lipoprotein cholesterol (LDL-C) concentrations, along with a notable elevation in high-density lipoprotein cholesterol (HDL-C) concentrations. PDPS also improved glucose tolerance and prevented fat accumulation in the liver and adipose tissue. Additionally, PDPS exhibited anti-inflammatory properties, evidenced by reduced levels of pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6) in the liver. Gut microbiota analysis indicated a shift toward beneficial bacteria, such as Romboutsia, Lachnospiraceae_NK4A136_group, Coriobacteriaceae_UCG-002, and Blautia. These findings suggest that PDPS may mitigate HFD-induced metabolic issues by enhancing lipid metabolism, glycemic control, and gut health, positioning it as a promising, sustainable functional ingredient for dietary interventions aimed at managing metabolic disorders.

Pediatric Non-Alcoholic Fatty Liver Disease (NAFLD): Trends, Mortality, and Socioeconomic Disparities in the U.S., 1998-2020

BACKGROUND/OBJECTIVES

We aim to describe the changing inpatient epidemiology of NAFLD in the U.S. and identify major risk factors associated with mortality in the disease among hospitalized pediatric patients.

METHODS

Hospitalization data from the 1998-2020 National Inpatient Sample were utilized. ICD-9 and ICD-10 codes were used to identify pediatric patients (age less than 18 years old) with NAFLD, and risk factors for mortality were analyzed by logistic regression.

RESULTS

We identified 68,869 pediatric hospitalizations involving NAFLD. Among those, 970 (1.4%) died during hospitalization. Hospitalization rates have been rapidly increasing from 1998 to 2020 (incidence rate ratio (IRR): 1.07; 95% CI: 1.06-1.07; p < 0.001). There was a significant difference in mortality based on the type of hospital (rural, non-teaching urban, or teaching urban) in pediatric patients with NAFLD (p < 0.05). Coagulopathy was significantly associated with increased odds of mortality, while age ≥ 12 years, diabetes and obesity were associated with decreased odds of mortality (p < 0.05). Sex, race/ethnicity, hepatitis B, hepatitis C, HIV, and IV drug use were not significantly associated with mortality.

CONCLUSIONS

Our study has shown ever increasing hospitalization rates for NAFLD in pediatric populations and well as significant risk factors associated with mortality. Further studies should be performed as more data on this patient population are collected.

Bile acid disorders and intestinal barrier dysfunction are involved in the development of fatty liver in laying hens

The pathogenesis of fatty liver is highly intricate. The role of the gut-liver axis in the development of fatty liver has gained increasing recognition in recent years. This study was conducted to explore the role of bile acid signaling and gut barrier in the pathogenesis of fatty liver. A total of 100 "Jing Tint 6" laying hens, 56-week-old, were used and fed basal diets until 60 weeks of age. At the end of the experiment, thirty individuals were selected based on the degree of hepatic steatosis. The hens with minimal hepatic steatosis (< 5 %) were chosen as healthy controls, while those with severe steatosis (> 33 %) in the liver were classified as the fatty liver group. Laying hens with fatty liver and healthy controls showed significant differences in body weight, liver index, abdominal fat ratio, feed conversion ratio (FCR), albumin height, Haugh unit, and biochemical indexes. The results of bile acid metabolomics revealed a clear separation in hepatic bile acid profiles between the fatty liver group and healthy controls, and multiple secondary bile acids were decreased in the fatty liver group, indicating disordered bile acid metabolism. Additionally, the mRNA levels of farnesoid X receptor (FXR) and genes related to bile acid transport were significantly decreased in both the liver and terminal ileum of hens with fatty liver. Moreover, the laying hens with fatty liver exhibited significant decreases in ileal crypt depth, the number of goblet cells, and the mRNA expression of tight junction-related proteins, alongside a significant increase in ileal permeability. Collectively, these findings suggest that disordered bile acids, suppressed FXR-mediated signaling, and impaired intestinal barrier function are potential factors promoting the development of fatty liver. These insights indicate that regulating bile acids and enhancing intestinal barrier function may become new preventive and therapeutic strategies for fatty liver in the near future.

Monte Carlo modeling of hepatic steatosis based on stereology and spatial distribution of fat droplets

BACKGROUND AND OBJECTIVE

To model hepatic steatosis in adult humans with non-alcoholic fatty liver disease based on stereology and spatial distribution of fat droplets from liver biopsy specimens.

METHODS

Histological analysis was performed on 30 adult human liver biopsy specimens with varying degrees of steatosis. Morphological features of fat droplets were characterized by gamma distribution function (GDF) in both two-dimensional (2D) and three-dimensional (3D) spaces from three aspects: 1) size distribution indicating non-uniformity of fat droplets in radius; 2) nearest neighbor distance distribution indicating heterogeneous accumulation (i.e., clustering) of fat droplets; 3) regional anisotropy indicating inter-regional variability in fat fraction (FF). To generalize the morphological description of hepatic steatosis to different FFs, correlation analysis was performed among the estimated GDF parameters and FFs for all specimens. Finally, Monte Carlo modeling of hepatic steatosis was developed to simulate fat droplet distribution in tissue.

RESULTS

Morphological features, including size and nearest neighbor distance in 2D and 3D spaces as well as regional anisotropy, statistically captured the distribution of fat droplets by the GDF fit (R2 > 0.54). The estimated GDF parameters (i.e., scale and shape parameters) and FFs were well correlated, with R2 > 0.55. In addition, simulated 3D liver morphological models demonstrated similar sections to real histological samples both visually and quantitatively.

CONCLUSIONS

The morphology of hepatic steatosis is well characterized by stereology and spatial distribution of fat droplets. Simulated models demonstrate similar appearances to real histological samples. Furthermore, the model may help understand MRI signal behavior in the presence of liver steatosis.

Glycine-β-muricholic acid antagonizes the intestinal farnesoid X receptor-ceramide axis and ameliorates NASH in mice

Nonalcoholic steatohepatitis (NASH) is a rapidly developing pathology around the world, with limited treatment options available. Some farnesoid X receptor (FXR) agonists have been applied in clinical trials for NASH, but side effects such as pruritus and low-density lipoprotein elevation have been reported. Intestinal FXR is recognized as a promising therapeutic target for metabolic diseases. Glycine-β-muricholic acid (Gly-MCA) is an intestine-specific FXR antagonist previously shown to have favorable metabolic effects on obesity and insulin resistance. Herein, we identify a role for Gly-MCA in the pathogenesis of NASH, and explore the underlying molecular mechanism. Gly-MCA improved lipid accumulation, inflammatory response, and collagen deposition in two different NASH models. Mechanistically, Gly-MCA decreased intestine-derived ceramides by suppressing ceramide synthesis-related genes via decreasing intestinal FXR signaling, leading to lower liver endoplasmic reticulum (ER) stress and proinflammatory cytokine production. The role of bile acid metabolism and adiposity was excluded in the suppression of NASH by Gly-MCA, and a correlation was found between intestine-derived ceramides and NASH severity. This study revealed that Gly-MCA, an intestine-specific FXR antagonist, has beneficial effects on NASH by reducing ceramide levels circulating to liver via lowering intestinal FXR signaling, and ceramide production, followed by decreased liver ER stress and NASH progression. Intestinal FXR is a promising drug target and Gly-MCA a novel agent for the prevention and treatment of NASH.

Hyperferritinemia Correlates to Metabolic Dysregulation and Steatosis in Chinese Biopsy-Proven Nonalcoholic Fatty Liver Disease Patients

PURPOSE

Elevated serum ferritin (SF), also defined as hyperferritinemia, is commonly seen in patients with nonalcoholic fatty liver disease (NAFLD). However, the clinical significance of SF in NAFLD remains controversial. The aim of this study was to characterize the NAFLD patients with elevated SF and to explore the association of hyperferritinemia with the severity of NAFLD proved by liver biopsy in the Chinese population.

PATIENTS AND METHODS

A total of 136 NAFLD patients proved by liver biopsy were enrolled. The demographic, anthropometric, clinical historic, laboratory, and histological characteristics were compared between elevated and normal SF groups. The independent factors for elevated SF were determined using multivariate logistic regression analysis.

RESULTS

The median age and body mass index were 41.00 (33.00-57.75) years and 28.28 (26.28-31.34) kg/m2, respectively. Hyperferritinemia was detected in 57 (41.9%) patients. Patients in the elevated SF group presented with more severe lipo- and glucometabolic disorder, and higher aminotransferases compared to those in the normal SF group (p < 0.05). In terms of histopathology, elevated SF was associated with worse steatosis and a higher proportion of positive iron staining (p < 0.05). Multivariate logistic regression analysis identified homeostasis model assessment of insulin resistance (OR: 1.170, 95% CI: 1.036-1.322, p = 0.012), alanine aminotransferase (OR: 1.012, 95% CI: 1.005-1.019, p < 0.001), and positive Perl's staining (OR: 4.880, 95% CI: 2.072-11.494, p < 0.001) as independent risk factors of hyperferritinemia.

CONCLUSION

NAFLD patients with hyperferritinemia were characterized as more severe metabolic dysfunction and liver injury. More attention should be paid to the metabolism state of NAFLD patients with elevated SF. Hyperferritinemia was correlated to hepatic steatosis in Chinese NAFLD patients.

Neutrophil extracellular traps induced by pro-inflammatory cytokines enhance procoagulant activity in NASH patients

BACKGROUND

Nonalcoholic steatohepatitis (NASH) patients are at a high risk of developing venous thromboembolism, with a high rate of morbidity and mortality. The role of neutrophil extracellular traps (NETs) in procoagulant activity (PCA) in patients with NASH remains unclear. Our study aimed to investigate the formation of NETs in NASH patients stimulated by specific pro-inflammatory factors. Moreover, we evaluated the pivotal role of NETs in the induction of hypercoagulability in NASH and the interaction between NETs and endothelial injury.

METHOD

The levels of the NETs biomarkers were evaluated in the plasma samples of 27 NASH patients and 18 healthy subjects. The formation of NETs was visualized using immunofluorescence microscopy. The PCA of the NETs was assessed using coagulation time, purified coagulation complex, and fibrin formation assays. Confocal microscopy was further used to evaluate the interactions between the NETs and HUVECs.

RESULTS

The levels of NETs markers in the plasma of NASH patients were significantly higher than healthy controls. NETs derived from NASH enhanced thrombin and fibrin formation and significantly reduced CT (p<0.05). The mixture of IL-6 and TNF-α triggered the NETs release in the plasma rather than them alone. Additionally, the NETs exerted cytotoxic effects on the endothelial cells, converting them to a procoagulant and pro-inflammatory phenotype, and DNase I could reverse these effects.

CONCLUSION

Our results revealed the primary role of NETs in promoting the hypercoagulable state in NASH patients. Methods that prevent the formation of NETs may be a novel approach for the prevention and treatment of NASH.

Pathological findings of liver steatosis that is difficult to evaluate with ultrasound

Although new ultrasound (US) methods able to quantitatively assess liver fat content have been recently developed, B-mode US is still the major method for detecting liver steatosis during medical checkups. However, some pathological cases yield false-positive or false-negative liver steatosis results using B-mode US. In addition, histologically, the degree of fat deposits and the size of fat droplets in the liver can affect the sensitivity and specificity of the diagnosis of liver steatosis using B-mode US. As B-mode US evaluation of fatty liver relies on operator expertise, the operator should be aware that there are some cases of liver steatosis that are difficult to evaluate with B-mode US. Here, we describe the pathological findings of liver steatosis that is difficult to evaluate with US.