Eliminating senescent cells by white adipose tissue-targeted senotherapy alleviates age-related hepatic steatosis through decreasing lipolysis

Cellular senescence is an important risk factor in the development of hepatic steatosis. Senolytics present therapeutic effects on age-related hepatic steatosis without eliminating senescent hepatocytes directly. Therefore, it highlights the need to find senolytics' therapeutic targets. Dysfunction of adipose tissue underlies the critical pathogenesis of lipotoxicity in the liver. However, the correlation between adipose tissue and hepatic steatosis during aging and its underlying molecular mechanism remains poorly understood. We explored the correlation between white adipose tissue (WAT) and the liver during aging and evaluated the effect of lipolysis of aged WAT on hepatic steatosis and hepatocyte senescence. We screened out the ideal senolytics for WAT and developed a WAT-targeted delivery system for senotherapy. We assessed senescence and lipolysis of WAT and hepatic lipid accumulation after treatment. The results displayed that aging accelerated cellular senescence and facilitated lipolysis of WAT. Free fatty acids (FFAs) generated by WAT during aging enhanced hepatic steatosis and induced hepatocyte senescence. The combined usage of dasatinib and quercetin was screened out as the ideal senolytics to eliminate senescent cells in WAT. To minimize non-specific distribution and enhance the effectiveness of senolytics, liposomes decorated with WAT affinity peptide P3 were constructed for senotherapy in vivo. In vivo study, WAT-targeted treatment eliminated senescent cells in WAT and reduced lipolysis, resulting in the alleviation of hepatic lipid accumulation and hepatocyte senescence when compared to non-targeted treatment, providing a novel tissue-targeted, effective and safe senotherapy for age-related hepatic steatosis.

miR-155-5p promotes hepatic steatosis via PICALM-mediated autophagy in aging hepatocytes

BACKGROUND

Hepatic steatosis, a lipid disorder characterized by the accumulation of intrahepatic fat, is more prevalent in the elderly population. This study investigates the role of miR-155-5p in the autophagy dysregulation of aging hepatic steatosis.

METHODS

We established an aging mouse model in vivo and a hepatocellular senescence model induced by low serum and palmitic acid in vitro. The fluctuations of microRNAs were derived from RNA-seq data and confirmed by qPCR in 4- and 18-month-old mouse liver tissues. Hematoxylin-eosin (H&E) staining observed pathological changes. Markers of senescence, autophagy, and lipolysis genes were analyzed using Western blot and qPCR. Bioinformatics analysis predicted miR-155-5p's target gene PICALM, confirmed by dual luciferase reporter assay and transfection of miR-155-5p mimic/inhibitor into senescent hepatocytes.

RESULTS

Senescent markers (p21, p16, and p-P53) and miR-155-5p were up-regulated in aging liver tissues and senescent hepatocytes. Bioinformatics analysis identified PICALM as a target gene of miR-155-5p, a finding further supported by dual luciferase reporter assays. Inhibition of miR-155-5p reduced expression of senescent marker genes (p16, p21, p-P53), improved autophagy (evidenced by increased LC3B-II and ATG5, and decreased P62), and enhanced lipolysis (indicated by increased ATGL and p-HSL) in senescent hepatocytes. Oil red O staining confirmed that miR-155-5p inhibition significantly reduced lipid accumulation in these cells.

CONCLUSIONS

This study suggests a potential new therapeutic approach for age-related hepatic steatosis through the inhibition of miR-155-5p to enhance autophagy.

Dapagliflozin ameliorates hepatic steatosis via suppressing LXRα-mediated synthesis of lipids and bile acids

Nonalcoholic fatty liver disease (NAFLD) prevalence is rising globally with no pharmacotherapies approved. Hepatic steatosis is closely associated with progression and prognosis of NAFLD. Dapagliflozin, kind of sodium-glucose cotransporter 2 (SGLT2) inhibitor, was found to improve NAFLD in clinical trials, while the underlying mechanism remains poorly elucidated. Here, we reported that dapagliflozin effectively mitigated liver injury and relieved lipid metabolism disorders in vivo. Further investigation showed that dapagliflozin markedly suppressed Liver X Receptor α (LXRα)-mediated synthesis of de novo lipids and bile acids (BAs). In AML12 cells, our results proved dapagliflozin decreased lipid contents via inhibiting the expression of LXRα and downstream liposynthesis genes. Proteosome inhibitor MG132 eliminated the effect of dapagliflozin on LXRα-mediated signaling pathway, which suggested that dapagliflozin downregulated LXRα expression through increasing LXRα degradation. Knockdown of LXRα with siRNA abolished the reduction of lipogenesis from dapagliflozin treatment, indicating that LXRα might be the pivotal target for dapagliflozin to exhibit the aforementioned benefits. Furthermore, the data showed that dapagliflozin reversed gut dysbiosis induced by BAs disruption and altered gut microbiota profile to reduce intestinal lipids absorption. Together, our study deciphered a novel mechanism by which dapagliflozin relieved hepatic steatosis and highlighted the potential benefit of dapagliflozin in treating NAFLD.

Association between serum trace element, mineral, and amino acid levels with non-alcoholic fatty liver disease (NAFLD) in adult women

The objective of the present study is assessment of serum trace element and amino acid levels in non-alcoholic fatty liver disease (NAFLD) patients with subsequent evaluation of its independent associations with markers of liver injury and metabolic risk.

MATERIALS AND METHODS

140 women aged 20-90 years old with diagnosed NAFLD and 140 healthy women with a respective age range were enrolled in the current study. Analysis of serum and hair levels of trace elements and minerals was performed with inductively-coupled plasma mass-spectrometry (ICP-MS). Serum amino acid concentrations were evaluated by high-pressure liquid chromatography (HPLC) with UV-detection. In addition, routine biochemical parameters including liver damage markers, alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT), were assessed spectrophotometrically.

RESULTS

The findings demonstrated that patients with NAFLD were characterized by higher ALT, GGT, lactate dehydrogenase (LDH) and cholinesterase (CE) activity, as well as increased levels of total cholesterol, low-density lipoprotein cholesterol, triglycerides, and uric acid. NAFLD patients were characterized by reduced serum and hair Co, Se, and Zn levels, as well as hair Cu content and serum Mn concentrations in comparison to controls. Circulating Ala, Cit, Glu, Gly, Ile, Leu, Phe, and Tyr levels in NAFLD patients exceeded those in the control group. Multiple linear regression demonstrated that serum and hair trace element levels were significantly associated with circulating amino acid levels after adjustment for age, BMI, and metabolic parameters including liver damage markers.

CONCLUSION

It is proposed that altered trace element handling may contribute to NAFLD pathogenesis through modulation of amino acid metabolism.

A combined extract containing Schisandra chinensis (SCE) reduced hepatic triglyceride accumulation in rats fed a high-sucrose diet

Excessive hepatic lipid accumulation is closely linked to inflammation, insulin resistance, and metabolic syndromes. We hypothesized that a combined extract containing Schisandra chinensis (SCE) could alleviate hepatic lipid accumulation. Male Sprague-Dawley rats fed a high-sucrose diet (HSD) were randomly assigned to three groups (n = 6): normal diet (ND), HSD (60% kcal from sucrose), and HSD + SCE (HSD with 2.44% SCE). Liquid chromatography-tandem mass spectrometry revealed that SCE contains chlorogenic acid (5.514 ± 0.009 mg/g) and schisandrin (0.179 ± 0.002 mg/g) as bioactive components. SCE did not alter the body weight, fat mass, lean mass, or glucose levels. Strikingly, SCE effectively reduced the plasma triglyceride (TG) and hepatic TG levels compared to the HSD group. Adiposity reduction is due to decreased activity of hepatic de novo lipogenic enzymes. These results indicated that SCE has nutraceutical potential for the prevention and treatment of hepatic steatosis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-023-01464-1.

Targeting GPX4-mediated Ferroptosis Alleviates Liver Steatosis in a Rat Model of Total Parenteral Nutrition

BACKGROUND

Parenteral nutrition-associated liver disease (PNALD) is a common hepatobiliary complication resulting from long-term parenteral nutrition (PN) that is associated with significant morbidity and mortality. Ferroptosis plays a significant role in the pathogenesis of various liver diseases. This study aims to explore the role of ferroptosis in PNALD and to uncover its underlying mechanisms.

METHODS

Ferroptosis was evaluated in pediatric patients with PNALD and in rats administered with total parenteral nutrition (TPN) as an animal model of PNALD. In TPN-fed rats, we applied liproxstatin-1 (Lip-1) to inhibit ferroptosis for 7 days and assessed its impact on liver steatosis. We performed RNA-seq analysis to profile the alterations in miRNAs in livers from TPN-fed rats. The ferroptosis-promoting effects of miR-431 were evaluated in HepG2 cells and the direct targeting effects on glutathione peroxidase 4 (GPX4) were evaluated in HEK293T cells.

RESULTS

RNA-seq analysis and experimental validation suggested that ferroptosis was increased in the livers of pediatric patients and rats with PNALD. Inhibiting ferroptosis with Lip-1 attenuated liver steatosis by regulating PPARα expression. RNA-seq analysis uncovered miR-431 as the most upregulated miRNA in the livers of TPN-fed rats, showing a negative correlation with hepatic GPX4 expression. In vitro studies demonstrated that miR-431 promoted ferroptosis by directly binding to the 3'UTR of GPX4 mRNA, resulting in the suppression of its expression.

CONCLUSIONS

Our study demonstrates that TPN induces the upregulation of miR-431 in rats, leading to activation of ferroptosis through downregulation of GPX4. Inhibition of ferroptosis attenuates TPN-induced liver steatosis by regulating PPARα expression.

Automated liver volumetry and hepatic steatosis quantification with magnetic resonance imaging proton density fat fraction

BACKGROUND

Preoperative imaging evaluation of liver volume and hepatic steatosis for the donor affects transplantation outcomes. However, computed tomography (CT) for liver volumetry and magnetic resonance spectroscopy (MRS) for hepatic steatosis are time consuming. Therefore, we investigated the correlation of automated 3D-multi-echo-Dixon sequence magnetic resonance imaging (ME-Dixon MRI) and its derived proton density fat fraction (MRI-PDFF) with CT liver volumetry and MRS hepatic steatosis measurements in living liver donors.

METHODS

This retrospective cross-sectional study was conducted from December 2017 to November 2022. We enrolled donors who received a dynamic CT scan and an MRI exam within 2 days. First, the CT volumetry was processed semiautomatically using commercial software, and ME-Dixon MRI volumetry was automatically measured using an embedded sequence. Next, the signal intensity of MRI-PDFF volumetric data was correlated with MRS as the gold standard.

RESULTS

We included the 165 living donors. The total liver volume of ME-Dixon MRI was significantly correlated with CT (r = 0.913, p < 0.001). The fat percentage measured using MRI-PDFF revealed a strong correlation between automatic segmental volume and MRS (r = 0.705, p < 0.001). Furthermore, the hepatic steatosis group (MRS ≥5%) had a strong correlation than the non-hepatic steatosis group (MRS <5%) in both volumetric (r = 0.906 vs. r = 0.887) and fat fraction analysis (r = 0.779 vs. r = 0.338).

CONCLUSION

Automated ME-Dixon MRI liver volumetry and MRI-PDFF were strongly correlated with CT liver volumetry and MRS hepatic steatosis measurements, especially in donors with hepatic steatosis.

The efficacy of antiviral treatment in chronic hepatitis B patients with hepatic steatosis

Background & aims

With a drastic increase in the number of chronic hepatitis B (CHB) patients with coexisting nonalcoholic fatty liver disease (NAFLD), there is an urgent need to evaluate antiviral treatment effects in this special population.

Methods

CHB patients with hepatic steatosis (CHB + HS) were prospectively recruited with followed-up of 3 years. HS and liver fibrosis were assessed by transient elastography. HS was defined as controlled attenuation parameter (CAP) ≥248 dB/m, and fibrosis progression was defined with ≥1-stage fibrosis increment. Multivariate and propensity score matching (PSM) analysis were used to evaluate antiviral therapy effects on fibrosis progression.

Results

In total 212 recruited CHB + HS patients (median age 36 years, median ALT 59 U/L), 49.1% (104/212) received antiviral therapy and 50.9% (108/212) did not. Among patients with antiviral therapy, rates of serum HBV DNA undetectable, HBeAg and HBsAg loss, and ALT normalization at year 3 were 88.5%, 31.0%, 8.7% and 70.2%, respectively. Patients with mild-moderate HS didn't differ patients with severe HS regarding biochemical and virological responses. Antiviral therapy was independently associated with a lower risk of fibrosis progression among the entire cohort (odds ratio 0.473, 95% CI 0.245-0.911, P = 0.025). This finding was further verified by PSM analysis. When stratified by the severity of HS, the antiviral therapy benefits in reducing fibrosis progression were mainly seen in patients with mild-moderate HS.

Conclusions

Among CHB + HS patients, long-term antiviral treatment effectively inhibits HBV replication and reduces fibrosis progression. Our findings have implications for the optimal management of this population.

The Janus of a disease: Diabetes and metabolic dysfunction-associated fatty liver disease

Metabolic Dysfunction-Associated Fatty Liver Disease and Diabetes Mellitus are two prevalent metabolic disorders that often coexist and synergistically contribute to the progression of each other. Several pathophysiological pathways are involved in the association, including insulin resistance, inflammation, and lipotoxicity, providing a foundation for understanding the complex interrelationships between these conditions. The presence of MASLD has a significant impact on diabetes risk and the development of microvascular and macrovascular complications, and diabetes significantly contributes to an increased risk of liver fibrosis progression in MASLD and the development of hepatocellular carcinoma. Moreover, both pathologies have a synergistic effect on cardiovascular events and mortality. Therapeutic interventions targeting MASLD and diabetes are discussed, considering lifestyle modifications, pharmacological agents, and emerging treatment modalities. The review also addresses the challenges in managing these comorbidities, such as the need for personalized approaches and the potential impact on cardiovascular health. The insights gleaned from this analysis can inform clinicians, researchers, and policymakers in developing integrated strategies for preventing, diagnosing, and managing these metabolic disorders.

Glucagon augments the secretion of FGF21 and GDF15 in MASLD by indirect mechanisms

INTRODUCTION

Glucagon receptor agonism is currently explored for the treatment of obesity and metabolic dysfunction-associated steatotic liver disease (MASLD). The metabolic effects of glucagon receptor agonism may in part be mediated by increases in circulating levels of Fibroblast Growth Factor 21 (FGF21) and Growth Differentiation Factor 15 (GDF15). The effect of glucagon agonism on FGF21 and GDF15 levels remains uncertain, especially in the context of elevated insulin levels commonly observed in metabolic diseases.

METHODS

We investigated the effect of a single bolus of glucagon and a continuous infusion of glucagon on plasma concentrations of FGF21 and GDF15 in conditions of endogenous low or high insulin levels. The studies included individuals with overweight with and without MASLD, healthy controls (CON) and individuals with type 1 diabetes (T1D). The direct effect of glucagon on FGF21 and GDF15 was evaluated using our in-house developed isolated perfused mouse liver model.

RESULTS

FGF21 and GDF15 correlated with plasma levels of insulin, but not glucagon, and their secretion were highly increased in MASLD compared with CON and T1D. Furthermore, FGF21 levels in individuals with overweight with or without MASLD did not increase after glucagon stimulation when insulin levels were kept constant. FGF21 and GDF15 levels were unaffected by direct stimulation with glucagon in the isolated perfused mouse liver.

CONCLUSION

The glucagon-induced secretion of FGF21 and GDF15 are augmented in MASLD and may depend on insulin. Thus, glucagon receptor agonism may augment its metabolic benefits in patients with MASLD through enhanced secretion of FGF21 and GDF15.

Hepatic steatosis modeling and MRI signal simulations for comparison of single- and dual-R2* models and estimation of fat fraction at 1.5T and 3T

BACKGROUND AND OBJECTIVE

Magnetic resonance imaging (MRI) has emerged as a noninvasive clinical tool for assessment of hepatic steatosis. Multi-spectral fat-water MRI models, incorporating single or dual transverse relaxation decay rate(s) (R2*) have been proposed for accurate fat fraction (FF) estimation. However, it is still unclear whether single- or dual-R2* model accurately mimics in vivo signal decay for precise FF estimation and the impact of signal-to-noise ratio (SNR) on each model performance. Hence, this study aims to construct virtual steatosis models and synthesize MRI signals with different SNRs to systematically evaluate the accuracy of single- and dual-R2* models for FF and R2* estimations at 1.5T and 3.0T.

METHODS

Realistic hepatic steatosis models encompassing clinical FF range (0-60 %) were created using morphological features of fat droplets (FDs) extracted from human liver biopsy samples. MRI signals were synthesized using Monte Carlo simulations for noise-free (SNRideal) and varying SNR conditions (5-100). Fat-water phantoms were scanned with different SNRs to validate simulation results. Fat water toolbox was used to calculate R2* and FF for both single- and dual-R2* models. The model accuracies in R2* and FF estimates were analyzed using linear regression, bias plot and heatmap analysis.

RESULTS

The virtual steatosis model closely mimicked in vivo fat morphology and Monte Carlo simulation produced realistic MRI signals. For SNRideal and moderate-high SNRs, water R2* (R2*W) by dual-R2* and common R2* (R2*com) by single-R2* model showed an excellent agreement with slope close to unity (0.95-1.01) and R2 > 0.98 at both 1.5T and 3.0T. In simulations, the R2*com-FF and R2*W-FF relationships exhibited slopes similar to in vivo calibrations, confirming the accuracy of our virtual models. For SNRideal, fat R2* (R2*F) was similar to R2*W and dual-R2* model showed slightly higher accuracy in FF estimation. However, in the presence of noise, dual-R2* produced higher FF bias with decreasing SNR, while leading to only marginal improvement for high SNRs and in regions dominated by fat and water. In contrast, single-R2* model was robust and produced accurate FF estimations in simulations and phantom scans with clinical SNRs.

CONCLUSION

Our study demonstrates the feasibility of creating virtual steatosis models and generating MRI signals that mimic in vivo morphology and signal behavior. The single-R2* model consistently produced lower FF bias for clinical SNRs across entire FF range compared to dual-R2* model, hence signifying that single-R2* model is optimal for assessing hepatic steatosis.

Curcuma wenyujin rhizomes extract ameliorates lipid accumulation

Curcuma wenyujin (C. wenyujin) is a medicinal plant that is traditionally used to treat blood stagnation, liver fibrosis, pain, and jaundice. In this study, we examined the effect of C. wenyujin rhizome extract on hepatic lipid accumulation both in vivo and in vitro. We found that the petroleum ether fraction of C. wenyujin rhizome extract (CWP) considerably reduced the accumulation of lipids in HepG2 cells treated with oleic and palmitic acid. Ultra-high-performance liquid chromatography coupled with LTQ-Orbitrap mass spectrometry was used to analyze the main chemical constituents of CWP, and 21 sesquiterpenes were identified. In vivo experiments revealed that the administration of CWP significantly reduced the body weight and serum total cholesterol (TC) level of low-density-lipoprotein receptor knockout mice treated with a high-fat diet without affecting their food intake. CWP also significantly reduced the levels of liver TC, liver triglycerides, aspartate transaminase, and alanine transaminase. Histological examination revealed that CWP dose-dependently reduced steatosis in liver tissue, significantly downregulated the expression of lipogenesis genes, and increased the β-oxidation of fatty acids. CWP also significantly increased autophagy-related proteins. In conclusion, CWP rich in sesquiterpenes reduces the accumulation of lipids in vivo and in vitro by improving lipid metabolism and activating autophagy.

Association between food insecurity and metabolic dysfunction-associated steatotic liver disease/significant fibrosis measured by fibroscan

PURPOSE

Studies evaluating food insecurity and metabolic dysfunction-associated steatotic liver disease (MASLD) and significant hepatic fibrosis are currently scarce. We evaluated the characteristics of food insecure individuals and whether food insecurity was associated with MASLD and significant hepatic fibrosis in the US population.

METHODS

In this cross-sectional study from the National Health and Nutrition Examination Survey 2017-2018, 3441 participants with complete data were enrolled. We defined MASLD and significant hepatic fibrosis (≥ F2) by transient elastography in the absence of other causes of liver disease. The detailed questionnaire assessed and categorized food security as high, marginal, low, and very low food security.

RESULTS

Food-insecure subjects were more likely to be female, younger, more impoverished, non-Hispanic blacks, Hispanics, and less likely to be educated, married, and physically active. Food insecurity increased the odds of the prevalence of MASLD by 42% (odds ratio [OR]: 1.42, 95% confidence interval [CI]: 1.12-1.78) after adjustment for demographic, lifestyle, and metabolic risk factors. The addition of diabetes and obesity did not change this association (OR: 1.36, 95% CI: 1.03-1.78). The multivariable model showed an independent relationship between food insecurity and significant hepatic fibrosis (OR: 1.40, 95% CI: 1.04-1.88) after adjustment for demographic, lifestyle, and metabolic risk factors, although the association was attenuated and changed insignificantly after adjustment for diabetes and obesity.

CONCLUSIONS

Food insecurity was associated with higher odds for MASLD. While there is a relationship between food insecurity and significant hepatic fibrosis, this relationship changed insignificantly after adjustment of diabetes and obesity.

Association between fatty liver index and controlled attenuation parameters as markers of metabolic dysfunction-associated fatty liver disease and bone mineral density: observational and two-sample Mendelian randomization studies

Previously observational studies did not draw a clear conclusion on the association between fatty liver diseases and bone mineral density (BMD). Our large-scale studies revealed that MAFLD and hepatic steatosis had no causal effect on BMD, while some metabolic factors were correlated with BMD. The findings have important implications for the relationship between fatty liver diseases and BMD, and may help direct the clinical management of MAFLD patients who experience osteoporosis and osteopenia.

PURPOSE

Liver and bone are active endocrine organs with several metabolic functions. However, the link between metabolic dysfunction-associated fatty liver disease (MAFLD) and bone mineral density (BMD) is contradictory.

METHODS

Using the UK Biobank and National Health and Nutrition Examination Survey (NHANES) dataset, we investigated the association between MAFLD, steatosis, and BMD in the observational analysis. We performed genome-wide association analysis to identify single-nucleotide polymorphisms associated with MAFLD. Large-scale two-sample Mendelian randomization (TSMR) analyses examined the potential causal relationship between MAFLD, hepatic steatosis, or major comorbid metabolic factors, and BMD.

RESULTS

After adjusting for demographic factors and body mass index, logistic regression analysis demonstrated a significant association between MAFLD and reduced heel BMD. However, this association disappeared after adjusting for additional metabolic factors. MAFLD was not associated with total body, femur neck, and lumbar BMD in the NHANES dataset. Magnetic resonance imaging-measured steatosis did not show significant associations with reduced total body, femur neck, and lumbar BMD in multivariate analysis. TSMR analyses indicated that MAFLD and hepatic steatosis were not associated with BMD. Among all MAFLD-related comorbid factors, overweight and type 2 diabetes showed a causal relationship with increased BMD, while waist circumference and hyperlipidemia had the opposite effect.

CONCLUSION

No causal effect of MAFLD and hepatic steatosis on BMD was observed in this study, while some metabolic factors were correlated with BMD. This has important implications for understanding the relationship between fatty liver disease and BMD, which may help direct the clinical management of MAFLD patients with osteoporosis.

Evolution of liver fibrosis in diabetic patients with NAFLD in a follow-up study: Hepatoprotective effects of sodium-glucose co-transporter-2 inhibitors

BACKGROUND AND AIMS

Patients with non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) are at high risk of hepatic fibrosis. To prospectively evaluate changes in fibrosis in diabetic patients with NAFLD, predisposing factors and sodium glucose cotransporter 2 inhibitors (SGLT2i) influence.

METHODS

237 T2DM outpatients (mean age 67 ± 9 years, 54% male) were enrolled and re-evaluated after 52 ± 10 months. At baseline and follow-up NAFLD and liver fibrosis (LSM) were detected by ultrasonography and Fibroscan®.

RESULTS

During follow-up an increase in LSM (6.0 ± 2.8 vs 5.8 ± 2.7 kPa, p = 0.02) and in the prescription of SGLT2i (20% vs 6%, p<0.001) was registered, despite stability of diabetic control. LSM worsened in 133(56%) subjects, 92 (39%) with worsening >10% from baseline. Patients with worsening versus non worsening of LSM had higher prevalence of increase in BMI during follow-up (45% vs 32%, p = 0.06) and lower SGLT2i prescription (15% vs 27%, p = 0.034). In multivariate analysis use of SGLT2-inhibitors at follow-up reduced the risk of LSM worsening (HR 0.34, 95% CI 0.13-0.88), even when considered>10% from baseline.

CONCLUSIONS

A high prevalence of fibrosis progression was observed in diabetic subjects with NAFLD over a nearly 5-years follow up and SGLT2-inhibitors seem to reduce the risk of worsening of liver stiffness.

Non-alcoholic fatty liver disease in patients with morbid obesity: the gut microbiota axis as a potential pathophysiology mechanism

BACKGROUND/AIM

Alterations in gut microbiota are associated with the pathogenesis of metabolic diseases, including metabolic-associated fatty liver disease (MAFLD). The aim of this study was to evaluate gut microbiota composition and functionality in patients with morbid obesity with different degrees of MAFLD, as assessed by biopsy.

SUBJECTS/METHODS

110 patients with morbid obesity were evaluated by biopsy obtained during bariatric surgery for MAFLD. Stool samples were collected prior to surgery for microbiota analysis.

RESULTS

Gut microbiota from patients with steatosis and non-alcoholic steatohepatitis (NASH) were characterized by an enrichment in Enterobacteriaceae (an ethanol-producing bacteria), Acidaminococcus and Megasphaera and the depletion of Eggerthellaceae and Ruminococcaceae (SCFA-producing bacteria). MAFLD was also associated with enrichment of pathways related to proteinogenic amino acid degradation, succinate production, menaquinol-7 (K2-vitamin) biosynthesis, and saccharolytic and proteolytic fermentation. Basic histological hepatic alterations (steatosis, necroinflammatory activity, or fibrosis) were associated with specific changes in microbiota patterns. Overall, the core microbiome related to basic histological alterations in MAFLD showed an increase in Enterobacteriaceae and a decrease in Ruminococcaceae. Specifically, Escherichia coli was associated with steatosis and necroinflammatory activity, whilst Escherichia-shigella was associated with fibrosis and necroinflammatory activity.

CONCLUSIONS

We established a link between gut microbiota alterations and histological injury in liver diagnosis using biopsy. Harmful products such as ethanol or succinate may be involved in the pathogenesis and progression of MAFLD. Thus, these alterations in gut microbiota patterns and their possible metabolic pathways could add information to the classical predictors of MAFLD severity and suggest novel metabolic targets.

Targeting metabolic-associated fatty liver disease in diabetic kidney disease: A call to action

Nonalcoholic fatty liver disease or metabolic-associated fatty liver disease (MAFLD) is a common condicion with increasing prevalence and incidence, specially in patients with type 2 diabetes mellitus (T2DM). Both cardiovascular and renal disease are clearly increased in these patients, particularly in those with diabetic nephropathy. In the liver-heart-kidney-metabolic axis, the common pathophysiological basis of MAFLD, cardiovascular disease (CVD), chronic kidney disease (CKD), and T2DM is the same. The clinical relationship between all of them is clear and is multidirectional: MAFLD may precede the development of cardiovascular and renal disease, and may also worsen the prognosis of these complications once developed. In this review we emphasize the importance of targeting MAFLD in Diabetic kidney disease, with the goal of detecting high-risk patients in order to improve their prognosis.

Risk factors of developing nonalcoholic fatty liver disease after pancreatic resection: a systematic review and meta-analysis

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) occurs in 10% to 40% of patients after pancreatic resection. Pancreatic exocrine insufficiency (PEI) is thought to be closely associated with NAFLD; however, the mechanism of NAFLD is not clearly understood. We perform a systematic review and meta-analysis to better understand the risk factors of NAFLD.

METHODS

A systematic literature search was performed in the MEDLINE database. Studies focused on the risk factors associated with NAFLD in patients undergoing pancreatectomy. The odds ratios (ORs) denoting the association of risk factors with NAFLD after resection were curated.

RESULTS

Of 814 published articles, 26 studies met the inclusion criteria. Combined, these studies included clinical data on 4055 patients. The pooled incidence of NAFLD was 29% (23%-35%). Among the various risk factors analyzed, the following had a significant likelihood of NAFLD on forest plot analysis: female gender (OR, 2.44), pancreatic ductal adenocarcinoma (OR, 2.11), portal vein or superior mesenteric vein resection (OR, 1.99), dissection of nerve plexus around the superior mesenteric artery (OR, 1.93), and adjuvant chemotherapy (OR, 1.58). Only 2 studies investigated 2 different measurements of quantitative PEI, which could not be used for analysis. Owing to heterogeneity of studies, pancreatic remanent volume, which is considered a marker for PEI could not be evaluated. Pancreatic enzyme replacement therapy (PERT) was not associated with NAFLD.

CONCLUSION

Numerous factors are associated with NAFLD after pancreatectomy. Previous research shows that PEI may be associated with NAFLD; however, this could not be compared in our meta-analysis. Further research is required to study the role of PERT in NAFLD.

The contribution of vitamin D insufficiency to the onset of steatotic liver disease among individuals with metabolic dysfunction

The interplay between fatty liver disease (FLD) and metabolic dysfunction has given rise to the concept of metabolic associated fatty liver disease (MAFLD). With vitamin D insufficiency frequently co-occurring with FLD and linked to metabolic abnormalities, this study investigates the potential role of vitamin D in the development of MAFLD. In this cross-sectional analysis, 22,476 participants with baseline metabolic dysfunction and known serum 25-OH-vitamin D3 levels were examined. The fatty liver index (FLI) was utilized to predict FLD, dividing subjects into MAFLD and non-MAFLD groups. Further stratification by vitamin D levels (sufficient vs. insufficient) and gender provided a detailed assessment through binary logistic regression to determine the association of vitamin D status with MAFLD incidence. Vitamin D insufficiency correlated with a higher MAFLD incidence in metabolically impaired individuals. Post-adjustment, the correlation was stronger (men: aOR = 1.32, 95% CI = 1.22-1.43, P < 0.001; women: aOR = 1.53, 95% CI = 1.18-1.98, P = 0.001). Lower serum 25-OH-vitamin D3 levels were found in MAFLD patients across genders (men: P = 0.003; women: P = 0.014), with a higher prevalence of insufficiency in MAFLD cases (men: P = 0.007; women: P = 0.003). The vitamin D-MAFLD link was stable across subgroups and using varying FLI criteria. Our findings indicate a clear association between vitamin D insufficiency and increased MAFLD incidence, underscoring the potential of vitamin D as an anti-lipogenic and anti-fibrotic agent.

PDGFRβ + cell HIF2α is dispensable for white adipose tissue metabolic remodeling and hepatic lipid accumulation in obese mice

BACKGROUND

Obesity is associated with extensive white adipose tissue (WAT) expansion and remodeling. Healthy WAT expansion contributes to the maintenance of energy balance in the liver, thereby ameliorating obesity-related hepatic steatosis. Tissue-resident mesenchymal stromal cell populations, including PDGFRβ + perivascular cells, are increasingly recognized pivotal as determinants of the manner in which WAT expands. However, the full array of regulatory factors controlling WAT stromal cell functions remains to be fully elucidated. Hypoxia-inducible factors (HIFs) are critical regulators in WAT stromal cell populations such as adipocyte precursor cells (APCs). It is revealed that HIF1α activation within PDGFRβ + stromal cells results in the suppression of de novo adipogenesis and the promotion of a pro-fibrogenic cellular program in obese animals. However, the role of HIF2α in PDGFRβ + cells remains undetermined in vivo.

METHODS

New genetic models were employed in which HIF1α (encoded by the Hif1a gene) and HIF2α (encoded by the Epas1 gene) are selectively inactivated in PDGFRβ + cells in an inducible manner using tamoxifen (TAM). With these models, both in vitro and in vivo functional analysis of PDGFRβ + cells lacking HIF proteins were performed. Additionally, comprehensive metabolic phenotyping in diet-induced mouse models were performed to investigate the roles of PDGFRβ + cell HIF proteins in WAT remodeling, liver energy balance and systemic metabolism.

RESULTS

Unlike HIF1α inactivation, the new findings in this study suggest that inducible ablation of HIF2α in PDGFRβ + cells does not cause apparent effects on WAT expansion induced by obesogenic diet. The adipogenic ability of PDGFRβ + APCs is not significantly altered by genetic HIF2α ablation. Moreover, no difference of key parameters associated with healthy WAT remodeling such as improvements of WAT insulin sensitivity, reduction in metabolic inflammation, as well as changes in liver fat accumulation or systemic glucose metabolism, is detected in PDGFRβ + cell Epas1-deficient mice.

CONCLUSION

The new findings in this study support that, in contrast to HIF1α, PDGFRβ + cell HIF2α appears dispensable for WAT metabolic remodeling and the resulting effects on liver metabolic homeostasis in diet-induced obesity, underscoring the isoform-specific roles of HIFα proteins in the regulation of adipose tissue biology.

Hepatic Steatosis but Not Fibrosis Is Independently Associated with Poor Outcomes in Patients with Inflammatory Bowel Disease

Background/Aims

Increased prevalence of nonalcoholic fatty liver disease (NAFLD) and inflammatory bowel disease (IBD) has been reported. However, the effects of NAFLD on the outcome of IBD remains unclear. We investigated whether the presence of NAFLD could influence the outcomes of patients with IBD.

Methods

We recruited 3,356 eligible patients with IBD into our study between November 2005 and November 2020. Hepatic steatosis and fibrosis were diagnosed using hepatic steatosis index of ≥30 and fibrosis-4 of ≥1.45, respectively. The primary outcome was clinical relapse, defined based on the following: IBD-related admission, surgery, or first use of corticosteroids, immunomodulators, or biologic agents for IBD.

Results

The prevalence of NAFLD in patients with IBD was 16.7%. Patients with hepatic steatosis and advanced fibrosis were older, had a higher body mass index, and were more likely to have diabetes (all p<0.05).

Conclusions

Hepatic steatosis was independently associated with increased risks of clinical relapse in patients with ulcerative colitis and Crohn's disease, whereas fibrotic burden in the liver was not. Future studies should investigate whether assessment and therapeutic intervention for NAFLD will improve the clinical outcomes of patients with IBD.

Hepatic steatosis predicts metachronous liver metastasis in colorectal cancer patients: a nested case-control study and systematic review

Nearly twenty-five percent of colorectal cancer (CRC) patients develop metachronous colorectal liver metastasis (CRLM) after curative surgery. Hepatosteatosis is the most prevalent liver condition worldwide, but its impact on the incidence of metachronous CRLM is understudied. In the present study, we aimed to investigate the predictive value of hepatic steatosis on the development of metachronous CRLM. First, a nested case-control study was conducted, enrolling stage I to III CRC patients in the National Colorectal Cancer Cohort (NCRCC) database. Metachronous CRLM patients and recurrence-free patients were matched via propensity-score matching. Fatty liver was identified based on treatment-naïve CT scans and the degree of hepatic fibrosis was scored. Multivariable analysis was conducted to investigate the association between fatty liver and metachronous CRLM. In our database, a total of 414 patients were included. Metachronous CRLM patients had considerably higher rates of hepatic steatosis (30.9% versus 15.9%, P<0.001) and highly fibrotic liver (11.6% versus 2.9%, P=0.001) compared to recurrence-free patients. Multivariable analysis showed that fatty liver (odds ratios [OR]=1.99, 95% confidence interval [CI] 1.19-3.30, P=0.008) and fibrotic liver (OR=4.27, 95% CI 1.54-11.81, P=0.005) were associated with high risk of metachronous CRLM. Further, a systematic literature review was performed to assess available evidence on the association between hepatosteatosis and development of metachronous CRLM. In the systematic review, 1815 patients were pooled from eligible studies, and hepatic steatosis remained a significant risk factor for metachronous CRLM (OR=1.90, 95% CI 1.35-2.66, P<0.001, I2=25.3%). In conclusion, our data suggest that patients with a steatotic liver and a high fibrosis score at CRC diagnosis have elevated risk of developing metachronous CRLM.

The micro-743a-3p-GSTM1 pathway is an endogenous protective mechanism against alcohol-related liver disease in mice

BACKGROUND AND AIMS

Epidemiological evidence suggests that the phenotype of glutathione S-transferase mu 1 (GSTM1), a hepatic high-expressed phase II detoxification enzyme, is closely associated with the incidence of alcohol-related liver disease (ALD). However, whether and how hepatic GSTM1 determines the development of ALD is largely unclear. This study was designed to elucidate the role and potential mechanism(s) of hepatic GSTM1 in the pathological process of ALD.

METHODS

GSTM1 was detected in the liver of various ALD mice models and cultured hepatocytes. Liver-specific GSTM1 or/and micro (miR)-743a-3p deficiency mice were generated by adenoassociated virus-8 delivered shRNA, respectively. The potential signal pathways involving in alcohol-regulated GSTM1 and GSTM1-associated ALD were explored via both genetic manipulation and pharmacological approaches.

RESULTS

GSTM1 was significantly upregulated in both chronic alcohol-induced mice liver and ethanol-exposed murine primary hepatocytes. Alcohol-reduced miR-743a-3p directly contributed to the upregulation of GSTM1, since liver specific silencing miR-743a-3p enhanced GSTM1 and miR-743a-3p loss protected alcohol-induced liver dysfunctions, which was significantly blocked by GSTM1 knockdown. GSTM1 loss robustly aggravated alcohol-induced hepatic steatosis, oxidative stress, inflammation, and early fibrotic-like changes, which was associated with the activation of apoptosis signal-regulating kinase 1 (ASK1), c-Jun N-terminal kinase (JNK), and p38. GSTM1 antagonized ASK1 phosphorylation and its downstream JNK/p38 signaling pathway upon chronic alcohol consumption via binding with ASK1. ASK1 blockage significantly rescued hepatic GSTM1 loss-enhanced disorders in alcohol-fed mice liver.

CONCLUSIONS

Chronic alcohol consumption-induced upregulation of GSTM1 in the liver provides a feedback protection against hepatic steatosis and liver injury by counteracting ASK1 activation. Down-regulation of miR-743a-3p improves alcohol intake-induced hepatic steatosis and liver injury via direct targeting on GSTM1. The miR-743a-3p-GSTM1 axis functions as an innate protective pathway to defend the early stage of ALD.

Advanced fibrosis leads to overestimation of steatosis with quantitative ultrasound in individuals without hepatic steatosis

PURPOSE

The effect of hepatic fibrosis stage on quantitative ultrasound based on the attenuation coefficient (AC) for liver lipid quantification is controversial. The objective of this study was to determine how the degree of fibrosis assessed by magnetic resonance (MR) elastography affects AC based on the ultrasound-guided attenuation parameter according to the grade of hepatic steatosis, using magnetic resonance imaging (MRI)-derived proton density fat fraction (MRIderived PDFF) as the reference standard.

METHODS

Between February 2020 and April 2021, 982 patients with chronic liver disease who underwent AC and MRI-derived PDFF measurement as well as MR elastography were enrolled. Multiple regression was used to investigate whether AC was affected by the degree of liver stiffness.

RESULTS

AC increased as liver stiffness progressed in 344 patients without hepatic steatosis (P=0.009). In multivariable analysis, AC was positively correlated with skin-capsule distance (P<0.001), MR elastography value (P=0.037), and MRI-derived PDFF (P<0.001) in patients without hepatic steatosis. In 52 of 982 patients (5%), the correlation between AC and MRIderived PDFF fell outside the 95% confidence interval for the regression line slope. Patients with MRI-derived PDFF lower than their AC (n=36) had higher fibrosis-4 scores, albumin-bilirubin scores, and MR elastography values than patients with MRI-derived PDFF greater than their AC (n=16; P=0.018, P=0.001, and P=0.011, respectively).

CONCLUSION

AC is affected by liver fibrosis (MR elastography value ≥6.7 kPa) only in patients without hepatic steatosis (MRI-derived PDFF <5.2%). These values should be interpreted with caution in patients with advanced liver fibrosis.

Maternal dietary copper deficiency induces cardiomyopathy and liver injury in mice by activating autophagy

Maternal nutritional deficiencies during pregnancy result in birth defects and elevate the risk of cardiovascular diseases and metabolic diseases. Accumulating evidence suggests that deficiency of copper, a fundamental trace element involved in several pivotal physiological processes, promotes the onset of multiple diseases, notably heart and liver diseases. Yet, exploration into the effects of maternal copper deficiency (CuD) on offspring is still limited. In this study, we hypothesized that maternal CuD induced cardiomyopathy and liver injury in offspring through the activation of autophagy. We established a maternal CuD mouse model by feeding pregnant C57BL/6 mice with a CuD diet until the end of the experiment. Echocardiography, histological analysis, western blotting, and quantitative polymerase chain reaction were performed on offspring at postnatal day 14. We found that maternal CuD caused growth retardation and early postnatal death in the offspring. Furthermore, our results revealed that CuD induced cardiac systolic dysfunction, cardiac hypertrophy, hepatic steatosis, and liver injury. Moreover, higher expression of LC3 and lower expression of p62 were observed in the heart tissues and liver tissues of CuD mice compared with the control group, indicating that CuD induced autophagy activation. In conclusion, maternal CuD caused severely deleterious effects on the heart and liver of the offspring via activating autophagy.

Chaenomeles sinensis (Thouin) Koehne fruit polyphenols alleviate high-fat diet-induced obesity and liver steatosis by improving lipid metabolism in mice

Chaenomeles sinensis (Thouin) Koehne fruit is a rich source of medicinally and nutritionally important natural phytochemicals that benefit human health. Based on the information provided, we hypothesized that Chaenomeles sinensis (Thouin) Koehne fruit polyphenols (CSFP) possessed in vivo protective effect of on high-fat diet (HFD)-induced obesity and hepatic steatosis. Specific pathogen-free male C57BL/6J mice were randomly divided into 3 groups and fed with a low-fat diet, HFD, or HFD supplemented with CSFP by intragastric administration for 14 weeks. Obesity-related biochemical indexes and hepatic gene expression profile were determined. The findings of this study demonstrated notable reductions in body weight gain, serum triglycerides, total cholesterol, low-density lipoprotein cholesterol, and steatosis grade in the group supplemented with CSFP compared with the HFD group. Gene expression analysis provided insights into the molecular mechanisms, demonstrating that CSFP downregulated the expression of key genes involved in lipogenesis (e.g., Fas, Fads2, Scd1) and upregulated the genes associated with fatty acid oxidation (e.g., Pparα, Cpt1a, Acox1), while also suppressing genes implicated in cholesterol homeostasis (e.g., HMGCoR, Insig1, AdipoR2). These molecular changes suggest that CSFP exerts protective effects by modulating hepatic lipid metabolism pathways, thereby mitigating the metabolic derangements associated with HFD-induced obesity and hepatic steatosis.

Metabolic effects of nuclear receptor activation in vivo after 28-day oral exposure to three endocrine-disrupting chemicals

Environmental exposure to endocrine-disrupting chemicals (EDCs) can lead to metabolic disruption, resulting in metabolic complications including adiposity, dyslipidemia, hepatic lipid accumulation, and glucose intolerance. Hepatic nuclear receptor activation is one of the mechanisms mediating metabolic effects of EDCs. Here, we investigated the potential to use a repeated dose 28-day oral toxicity test for identification of EDCs with metabolic endpoints. Bisphenol A (BPA), pregnenolone-16α-carbonitrile (PCN), and perfluorooctanoic acid (PFOA) were used as reference compounds. Male and female wild-type C57BL/6 mice were orally exposed to 5, 50, and 500 μg/kg of BPA, 1000, 10 000, and 100 000 µg/kg of PCN and 50 and 300 μg/kg of PFOA for 28 days next to normal chow diet. Primary endpoints were glucose tolerance, hepatic lipid accumulation, and plasma lipids. After 28-day exposure, no changes in body weight and glucose tolerance were observed in BPA-, PCN-, or PFOA-treated males or females. PCN and PFOA at the highest dose in both sexes and BPA at the middle and high dose in males increased relative liver weight. PFOA reduced plasma triglycerides in males and females, and increased hepatic triglyceride content in males. PCN and PFOA induced hepatic expression of typical pregnane X receptor (PXR) and peroxisome proliferator-activated receptor (PPAR)α target genes, respectively. Exposure to BPA resulted in limited gene expression changes. In conclusion, the observed changes on metabolic health parameters were modest, suggesting that a standard repeated dose 28-day oral toxicity test is not a sensitive method for the detection of the metabolic effect of EDCs.

Reliability and stability of ultrasound-guided attenuation parameter in evaluating hepatic steatosis

PURPOSE

This study aimed to explore the reliability and stability of ultrasound-guided attenuation parameter (UGAP) values obtained by two measuring methods and different measuring times.

METHODS

Patients who underwent liver UGAP examinations in our hospital from September 2022 to December 2022 were retrospectively analyzed. The clinical data and UGAP measurements results were collected. Two different measuring methods: static single-frame multi-point measuring and dynamic multi-frame single-point measuring, were performed for each patient, and 10 UGAP values of each measuring method were recorded. The medians of the UGAP values of the 1st-3rd, 1st-5th, 1st-7th and 1st-10th by each measuring method were taken as the final UGAP values of measuring 3, 5, 7 and 10 times. The UGAP values obtained by the two different measuring methods and different measuring times (3, 5, 7 or 10 times) were compared.

RESULTS

206 patients were included in this study. There was no statistical difference between UGAP values measured by static single-frame multi-point measuring and dynamic multi-frame single-point measuring (P = 0.689, P = 0.270, P = 0.298, P = 0.091), regardless of measuring times (3, 5, 7, 10 times). No significant difference between the UGAP values obtained by 3, 5, 7 and 10 measurements was found (P = 0.554, P = 0.916).

CONCLUSION

The UGAP values obtained by the two different measuring methods and different measuring times (3, 5, 7 and 10 times) are stable and reliable. Additionally, 3 times of UGAP measurements might be enough for each patient in clinical practice.

Cyy-287, a novel pyrimidine-2,4-diamine derivative, efficiently mitigates inflammatory responses, fibrosis, and lipid synthesis in obesity-induced cardiac and hepatic dysfunction

Background

Inflammation and metabolic disorders are important factors in the occurrence and development of obesity complications. In this study, we investigated the protective effect and underlying mechanism of a novel pyrimidine-2,4-diamine derivative, Cyy-287, on mice fed a high-fat diet (HFD).

Methods

The mice were randomly separated into four groups (n ≥ 7): control (regular diet), HFD, HFD with Cyy-287 (5 mg/kg), and HFD with Cyy-287 (20 mg/kg) following HFD feeding for 10 weeks. After a 10-week administration, ALT and AST enzymes, echocardiography, immunohistochemical (IHC), Western blot (WB), Masson and Sirius Red staining were used to evaluate functional and morphological changes to the heart and liver. Microsomes from the mouse liver were extracted to quantify the total amount of CYP450 enzymes after drug treatment.

Results

Cyy-287 decreased the levels of serum glucose, LDL, TC, ALT, and AST activities in HFD-treated mice. However, Cyy-287 administration increased ejection fraction (EF) and fractional shortening (FS) index of the heart. Cyy-287 inhibited histopathological changes in the heart and liver; decreased inflammatory activity; significantly diminished p38 mitogen-activated protein kinase (MAPK), the nuclear factor-kappa B (NF-κB) axis, and sterol regulatory element-binding protein-1c (SREBP-1c); and upregulated the AMP-activated protein kinase (AMPK) pathway in HFD-treated mice. Cyy-287 restored the content of hepatic CYP450 enzymes.

Conclusion

These findings demonstrated that Cyy-287 protected heart and liver cells from obesity-induced damage by inhibiting inflammation, fibrosis, and lipid synthesis.

Positive association between proinsulin and fatty liver index in people with type 2 diabetes

The post-hoc study, derived from our previous prospective observational study, investigated the association between fasting serum proinsulin levels and hepatic steatosis in people with type 2 diabetes. The severity of hepatic steatosis was assessed using the fatty liver index. A total of 268 participants were divided into three groups: low (n = 110), moderate (n = 75), and high fatty liver index (n = 83). In both the crude and age/sex-adjusted analysis, logarithm-transformed proinsulin was significantly higher in the high fatty liver index group than in the low or moderate groups (all p < 0.01). The moderate fatty liver index group showed higher logarithm-transformed proinsulin than the low group (both p < 0.01). Positive associations between proinsulin and fatty liver index shown in this study would support an involvement of hepato-pancreatic crosstalk in the pathophysiology of type 2 diabetes.

Comparative study of ultrasound attenuation analysis and controlled attenuation parameter in the diagnosis and grading of liver steatosis in non-alcoholic fatty liver disease patients

PURPOSE

To assess the diagnostic performance of Ultrasound Attenuation Analysis (USAT) in the diagnosis and grading of hepatic steatosis in patients with non-alcoholic fatty liver disease (NAFLD) using Controlled Attenuation Parameters (CAP) as a reference.

MATERIALS AND METHODS

From February 13, 2023, to September 26, 2023, participants underwent CAP and USAT examinations on the same day. We used manufacturer-recommended CAP thresholds to categorize the stages of hepatic steatosis: stage 1 (mild) - 240 dB/m, stage 2 (moderate) - 265 dB/m, stage 3 (severe) - 295 dB/m. Receiver Operating Characteristic curves were employed to evaluate the diagnostic accuracy of USAT and determine the thresholds for different levels of hepatic steatosis.

RESULTS

Using CAP as the reference, we observed that the average USAT value increased with the severity of hepatic steatosis, and the differences in USAT values among the different hepatic steatosis groups were statistically significant (p < 0.05). There was a strong positive correlation between USAT and CAP (r = 0.674, p < 0.0001). When using CAP as the reference, the optimal cut-off values for diagnosing and predicting different levels of hepatic steatosis with USAT were as follows: the cut-off value for excluding the presence of hepatic steatosis was 0.54 dB/cm/MHz (AUC 0.96); for mild hepatic steatosis, it was 0.59 dB/cm/MHz (AUC 0.86); for moderate hepatic steatosis, it was 0.73 dB/cm/MHz (AUC 0.81); and for severe hepatic steatosis, it was 0.87 dB/cm/MHz (AUC 0.87).

CONCLUSION

USAT exhibits strong diagnostic performance for hepatic steatosis and shows a high correlation with CAP values.

Acyl ghrelin, desacyl ghrelin and their ratio affect hepatic steatosis via PPARγ signaling pathway

BACKGROUND AND STUDY AIMS

Ghrelin is an appetite hormone-containing 28-amino acid and has 4 different forms in the body. Ghrelin forms have different physiological functions in the body. This study aims to analyze the effect of acyl and desacyl ghrelin hormone on hepatic steatosis and biochemical findings in 36 male Wistar rats.

MATERIALS AND METHODS

Rats were split into 6 equal groups, consisting of control, acyl ghrelin, desacyl ghrelin, acyl/desacyl 3:1, acyl/desacyl 1:1, and acyl/desacyl 1:3 groups, and administered placebo or 200 ng/kg hormone subcutaneous twice a day for 14 days. Oral Glucose Tolerance Test (OGTT) was performed on Day 15, Insulin Tolerance Test (ITT) on Day 16, and scarification procedure on Day 17. Certain biochemical data and liver diacylglycerol (DAG), glycogen, protein kinase C and PPAR-γ levels were detected in the blood. Histological analyses were also conducted on the liver tissues.

RESULTS

The highest plasma total cholesterol and VLDL-K levels were found in the acyl/desacyl 1:3 group, and lower insulin, and HOMA-IR levels were found in groups where acyl and desacyl were administered together (p < 0.05). PPAR-γ gene expression level increased in acyl ghrelin and acyl/desacyl 1:3 groups compared to the control group. Protein kinase C gene expression was highest in the acyl/desacyl 1:3 group. The most severe degenerative findings compliant with steatosis in the liver were observed in the acyl ghrelin group (p < 0.05).

CONCLUSION

It was determined that administering rats acyl alone and acyl/desacyl by 1:3 caused the highest PPAR-γ gene expression, serum total cholesterol, HDL-K, and VLDL-K levels in the body. Besides, it is shown that desacyl ghrelin effectively regulates the blood glucose level when administered alone.

Compromised very-low density lipoprotein induced polyunsaturated triglyceride accumulation in N-nitrosodiethylamine-induced hepatic steatosis

N-Nitrosodiethylamine (NDEA), a carcinogen in some foods and medications, is linked to liver damage similar to non-alcoholic fatty liver disease (NAFLD). This study explores how NDEA disrupts liver lipid metabolism. Sprague-Dawley rats were given two doses of NDEA (100 mg/kg) orally, 24 h apart. Liver response was assessed through tissue staining, blood tests, and biochemical markers, including fatty acids, lipid peroxidation, and serum very-low density lipoprotein (VLDL) levels. Additionally, lipidomic analysis of liver tissues and serum was performed. The results indicated significant hepatic steatosis (fat accumulation in the liver) following NDEA exposure. Blood analysis showed signs of inflammation and liver damage. Biochemical tests revealed decreased liver protein synthesis and specific enzyme alterations, suggesting liver cell injury but maintaining mitochondrial function. Increased fatty acid levels without a rise in lipid peroxidation were observed, indicating fat accumulation. Lipidomic analysis showed increased polyunsaturated triglycerides in the liver and decreased serum VLDL, implicating impaired VLDL transport in liver dysfunction. In conclusion, NDEA exposure disrupts liver lipid metabolism, primarily through the accumulation of polyunsaturated triglycerides and impaired fat transport. These findings provide insight into the mechanisms of NDEA-induced liver injury and its progression to hepatic steatosis.

Gracilaria chorda subcritical water ameliorates hepatic lipid accumulation and regulates glucose homeostasis in a hepatic steatosis cell model and obese C57BL/6J mice

ETHNOPHARMACOLOGICAL RELEVANCE

Red seaweed, known as Rhodophyta, has a long history of use in traditional Asian medicine, including Traditional Chinese Medicine and Ayurveda. It is believed to have cooling and detoxification properties. Red seaweed species, such as Gracilaria, have been used in traditional remedies to address various conditions, such as inflammation, thyroid disorders, and digestive issues.

AIM OF THE STUDY

Obesity is a risk factor of hepatic steatosis, a hallmark of non-alcoholic fatty liver disease (NAFLD) that affects nearly 25% of the worldwide population. Gracilaria chorda (GC) contains bioactive peptides that may be applicable in the prevention of metabolic syndrome diseases. This study investigated the effects of GC subcritical water extract at 210 °C (GCSW210) on preventing liver injury and lipid and glucose dysregulation in an oleic acid (OA)-induced hepatic steatosis cell model (HepG2) and high-fat diet (HFD)-induced obese animal model (C57BL/6J mice).

MATERIALS AND METHODS

Human hepatoma HepG2 cells were exposed to 0.1 mM OA for 24 h to induce hepatic steatosis and C57BL/6J mice were fed a HFD for 13 weeks. For lipid accumulation, triglyceride (TG) content was measured in both models, along with free fatty acid (FFA), plasma glucose, and insulin levels in HFD-fed mice. Protein expression of master regulators of adipogenesis and lipogenesis, as well as cholesterol and mitochondrial biosynthesis, was studied via western blotting in hepatic steatosis-induced in vitro and in vivo models. In addition, protein expression of the insulin signaling cascade in skeletal muscle tissues of HFD-fed mice was studied.

RESULTS

GCSW210 significantly decreased lipid accumulation in HepG2 cells exposed to OA and suppressed the expression of lipogenic factors, such as sterol regulatory element-binding protein (SREBP)-1c and fatty acid synthase. In addition, GCSW210 abrogated transcription factors related to cholesterol biosynthesis, such as SREBP-2 and low-density lipoprotein receptor. Similarly, FFA, TG, serum glutamic acid, aspartate transaminase, alanine transferase, plasma glucose, and insulin levels were also significantly reduced in GCSW210-treated HFD-fed mice, which were comparable to the positive control mice treated with Garcinia cambogia extract. Additionally, GCSW210 enhanced the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase in the hepatic tissues of HFD-fed mice. Moreover, GCSW210 treatment improved insulin signal transduction by reducing insulin receptor substrate 1 Ser307 phosphorylation and elevated phosphatidylinositol 3-kinase/protein kinase B and glucose transporter type 4 protein expression in muscle tissue. 5-Hdroxymethylfufural (5-HMF) was confirmed to be active substances isolated from GCSW210 through LC-PDA and LC-MS.

CONCLUSIONS

GCSW210 significantly regulated glucose metabolism, alleviated insulin resistance (IR) induced by high fatty acid synthesis and lipid accumulation, and elevated de novo lipogenesis by activating AMPK phosphorylation in both the liver and muscle tissues of HFD-fed mice. GCSW210 may be a potential functional food for preventing HFD-induced metabolic diseases, such as IR, NAFLD, and type 2 diabetes mellitus.

What are the common downstream molecular events between alcoholic and nonalcoholic fatty liver?

Liver fat storage, also called hepatic steatosis, is increasingly common and represents a very frequent diagnosis in the medical field. Excess fat is not without consequences. In fact, hepatic steatosis contributes to the progression toward liver fibrosis. There are two main types of fatty liver disease, alcoholic fatty liver disease (AFLD) and nonalcoholic fatty liver disease (NAFLD). Although AFLD and NAFLD are similar in their initial morphological features, both conditions involve the same evolutive forms. Moreover, there are various common mechanisms underlying both diseases, including alcoholic liver disease and NAFLD, which are commonalities. In this Review, the authors explore similar downstream signaling events involved in the onset and progression of the two entities but not completely different entities, predominantly focusing on the gut microbiome. Downstream molecular events, such as the roles of sirtuins, cytokeratins, adipokines and others, should be considered. Finally, to complete the feature, some new tendencies in the therapeutic approach are presented.

High fat diet-induced downregulation of TRPV2 mediates hepatic steatosis via p21 signalling

The global prevalence and incidence of non-alcoholic fatty liver disease (NAFLD) are exhibiting an increasing trend. NAFLD is characterized by a significant accumulation of lipids, though its underlying mechanism is still unknown. Here we report that high-fat diet (HFD) feeding induced hepatic steatosis in mice, which was accompanied by a reduction in the expression and function of hepatic TRPV2. Moreover, conditional knockout of TRPV2 in hepatocytes exacerbated HFD-induced hepatic steatosis. In an in vitro model of NAFLD, TRPV2 regulated lipid accumulation in HepG2 cells, and TRPV2 activation inhibited the expression of the cellular senescence markers p21 and p16, all of which were mediated by AMPK phosphorylation. Finally, we found that administration of probenecid, a TRPV2 agonist, impaired HFD-induced hepatic steatosis and suppressed HFD-induced elevation in p21 and p16. Collectively, our findings imply that hepatic TRPV2 protects against the accumulation of lipids by modulating p21 signalling.

Fatty liver index (FLI): more than a marker of hepatic steatosis

Fatty liver index (FLI) was developed as a simple and accurate marker of hepatic steatosis. FLI is derived from an algorithm based on body mass index, waist circumference, and levels of triglycerides and gamma-glutamyltransferase, and it is widely used in clinical and epidemiological studies as a screening tool for discriminating between healthy and nonalcoholic fatty liver disease (NAFLD) subjects. However, a systematic review of the literature regarding FLI revealed that this index has more extensive relationships with biochemical and physiological parameters. FLI is associated with key parameters of lipid, protein and carbohydrate metabolism, hormones, vitamins and markers of inflammation, or oxidative stress. FLI can be a predictor or risk factor for a number of metabolic and nonmetabolic diseases and mortality. FLI is also used as an indicator for determining the effects of health-related prevention interventions, medications, and toxic substances on humans. Although in most cases, the exact mechanisms underlying these associations have not been fully elucidated, they are most often assumed to be mediated by insulin resistance, inflammation, and oxidative stress. Thus, FLI may be a promising marker of metabolic health due to its multiple associations with parameters of physiological and pathological processes. In this context, the present review summarizes the data from currently available literature on the associations between FLI and biochemical variables and physiological functions. We believe that this review will be of interest to researchers working in this area and can provide new perspectives and directions for future studies on FLI.

A nutraceutical with Citrus bergamia and Cynara cardunculus improves endothelial function in adults with non-alcoholic fatty liver disease

OBJECTIVE

Polyphenol intake may prevent hepatic steatosis and cardiovascular disease by potentially improving endothelial function. The purposes of this study are to investigate the association between fatty liver disease and endothelial dysfunction and to test the effects of a nutraceutical containing extracts made from Citrus bergamia and Cynara cardunculus on peripheral vascular endothelial function in adults with liver steatosis.

METHODS

We analyzed data from 32 individuals with hepatic steatosis and endothelial dysfunction (reactive hyperemia index ≤ 1.67). Sixteen subjects took 1 capsule/d (300 mg/d) containing Cynara cardunculus extract and bergamot polyphenol fraction, while the other 16 subjects matched for age, sex, and body mass index took 1 capsule/d of placebo (maltodextrin) for 12 wk. All anthropometric parameters were assessed at baseline and after 12 wk as were lipids, glucose, and reactive hyperemia index using an EndoPAT 2000.

RESULTS

The mean age was 52 ± 9 y. The mean reactive hyperemia index was 1.15 ± 0.4. After 12 wk, we found a greater increase in reactive hyperemia index in the participants taking the nutraceutical rather than placebo (0.58 ± 0.5 versus 0.13 ± 0.5; P = 0.02, respectively). The stepwise multivariable analysis confirmed a positive association between reactive hyperemia index change and the nutraceutical treatment (B = 0.38; P = 0.025) and negative association with reactive hyperemia index values at baseline (B = -0.81; P < 0.001). No association was found between the reduction in the amount of intrahepatic fat and the improvement of endothelial function (B = 0.002; P = 0.56).

CONCLUSIONS

A nutraceutical containing bergamot and artichoke extracts improves peripheral vascular endothelial function in adults with hepatic steatosis and early phase of atherosclerosis.

Development of a machine learning-based model to predict hepatic inflammation in chronic hepatitis B patients with concurrent hepatic steatosis: a cohort study

Background

With increasingly prevalent coexistence of chronic hepatitis B (CHB) and hepatic steatosis (HS), simple, non-invasive diagnostic methods to accurately assess the severity of hepatic inflammation are needed. We aimed to build a machine learning (ML) based model to detect hepatic inflammation in patients with CHB and concurrent HS.

Methods

We conducted a multicenter, retrospective cohort study in China. Treatment-naive CHB patients with biopsy-proven HS between April 2004 and September 2022 were included. The optimal features for model development were selected by SHapley Additive explanations, and an ML algorithm with the best accuracy to diagnose moderate to severe hepatic inflammation (Scheuer's system ≥ G3) was determined and assessed by decision curve analysis (DCA) and calibration curve. This study is registered with ClinicalTrials.gov (NCT05766449).

Findings

From a pool of 1,787 treatment-naive patients with CHB and HS across eleven hospitals, 689 patients from nine of these hospitals were chosen for the development of the diagnostic model. The remaining two hospitals contributed to two independent external validation cohorts, comprising 509 patients in validation cohort 1 and 589 in validation cohort 2. Eleven features regarding inflammation, hepatic and metabolic functions were identified. The gradient boosting classifier (GBC) model showed the best performance in predicting moderate to severe hepatic inflammation, with an area under the receiver operating characteristic curve (AUROC) of 0.86 (95% CI 0.83-0.88) in the training cohort, and 0.89 (95% CI 0.86-0.92), 0.76 (95% CI 0.73-0.80) in the first and second external validation cohorts, respectively. A publicly accessible web tool was generated for the model.

Interpretation

Using simple parameters, the GBC model predicted hepatic inflammation in CHB patients with concurrent HS. It holds promise for guiding clinical management and improving patient outcomes.

Funding

This research was supported by the National Natural Science Foundation of China (No. 82170609, 81970545), Natural Science Foundation of Shandong Province (Major Project) (No. ZR2020KH006), Natural Science Foundation of Jiangsu Province (No.BK20231118), Tianjin Key Medical Discipline (Specialty), Construction Project, TJYXZDXK-059B, Tianjin Health Science and Technology Project key discipline special, TJWJ2022XK034, and Research project of Chinese traditional medicine and Chinese traditional medicine combined with Western medicine of Tianjin municipal health and Family Planning Commission (2021022).

FoxO6-Mediated TXNIP Induces Lipid Accumulation in the Liver through NLRP3 Inflammasome Activation

BACKGRUOUND

Hepatic steatosis, which involves the excessive accumulation of lipid droplets in hepatocytes, presents a significant global health concern due to its association with obesity and metabolic disorders. Inflammation plays a crucial role in the progression of hepatic steatosis; however, the precise molecular mechanisms responsible for this process remain unknown.

METHODS

This study investigated the involvement of the nucleotide-binding oligomerization domain-like receptor pyrin domain-containing-3 (NLRP3) inflammasome and the forkhead box O6 (FoxO6) transcription factor in the pathogenesis of hepatic steatosis. We monitored the NLRP3 inflammasome and lipogenesis in mice overexpressing the constitutively active (CA)-FoxO6 allele and FoxO6-null mice. In an in vitro study, we administered palmitate to liver cells overexpressing CA-FoxO6 and measured changes in lipid metabolism.

RESULTS

We administered palmitate treatment to clarify the mechanisms through which FoxO6 activates cytokine interleukin (IL)-1β through the NLRP3 inflammasome. The initial experiments revealed that dephosphorylation led to palmitate-induced FoxO6 transcriptional activity. Further palmitate experiments showed increased expression of IL-1β and the hepatic NLRP3 inflammasome complex, including adaptor protein apoptotic speck protein containing a caspase recruitment domain (ASC) and pro-caspase-1. Furthermore, thioredoxin-interacting protein (TXNIP), a key regulator of cellular redox conditions upstream of the NLRP3 inflammasome, was induced by FoxO6 in the liver and HepG2 cells.

CONCLUSION

The findings of this study shed light on the molecular mechanisms underpinning the FoxO6-NLRP3 inflammasome axis in promoting inflammation and lipid accumulation in the liver.

Tri-ortho-cresyl phosphate induces hepatic steatosis by mTOR activation and ER stress induction

Tri-ortho-cresyl phosphate (TOCP), an organophosphorus compound (OP), which is widely used as plasticizer, flame retardant and other industrial products, has been reported to cause multiple toxicities including neurotoxicity and reproductive toxicity. However, it remains to be elusive whether TOCP induces hepatotoxicity. The purpose of this study was to investigate the effect of TOCP on hepatocytes and the lipid metabolism in particular. The adult mice were given a single dose of TOCP (800 mg/kg, p.o.) and the histological changes in liver tissue and lipid content in serum were determined. The results showed that more vacuoles and lipid droplets were observed in the liver of the mice exposed to TOCP. And triglyceride concentrations in serum and liver tissue significantly increased. However, the histopathological changes of the liver and the elevated triglyceride levels in the exposed mice can be reversed by endoplasmic reticulum (ER) stress inhibitor 4-phenylbutyric acid and mTOR signal inhibitor rapamycin. It was also found that the changes of expression levels of the biomarkers of ER stress and mTOR signaling pathway, such as GRP78, CHOP, and p-mTOR, in the exposed mice were consistent with those observed in the cultured primary hepatocytes treated with the same chemicals. These results showed that TOCP activated mTOR signal and ER stress to induce de novo lipid synthesis, which led to the hepatic steatosis in mouse.

Correlation analysis of hepatic steatosis and hepatitis B virus: a cross-sectional study

BACKGROUND

The co-occurrence of chronic hepatitis B (CHB) and metabolic dysfunction-associated fatty liver disease (MAFLD) has drawn considerable attention due to its impact on disease outcomes. This study aimed to investigate the association between hepatic steatosis and hepatitis B virus (HBV) and analyzed the influence of hepatic steatosis on hepatitis B virology in patients with CHB.

METHODS

In this cross-sectional study, 272 patients infected with HBV who were treatment-naïve or had ceased antiviral treatment for > 6 months were categorized into the CHB group (n = 128) and CHB + MAFLD group (n = 144). Furthermore, based on whether HBV DNA was higher than 2000 IU/mL, patients were categorized into the high-level HBV DNA group (n = 129) and the low-level HBV DNA group (n = 143). The impact of hepatic steatosis on hepatitis B virology was analyzed within the CHB cohort. Multivariate logistic regression analysis was employed to identify independent factors influencing pre-genomic RNA (pgRNA) levels below the lower limit of detection (LLD) in patients with CHB.

RESULTS

Among the 272 patients, compared with CHB group, HBV DNA levels (4.11 vs. 3.62 log10 IU/mL, P = 0.045), hepatitis B surface antigen (HBsAg) levels (3.52 vs. 3.20 log10 IU/mL, P = 0.008) and the hepatitis B e antigen (HBeAg) positive rate (33.6% vs. 22.2%, P = 0.036) were significantly decreased in the CHB + MAFLD group; In 143 low-level HBV DNA patients, the CHB + MAFLD group exhibited decreased levels of pgRNA and HBsAg compared to the CHB group. However, in 129 high-level HBV DNA patients, a more significant decrease was observed in pgRNA (3.85 vs 3.35 log10 copies/mL, P = 0.044) and HBsAg (3.85 vs 3.59 log10 IU/mL, P = 0.033); Spearman correlation analysis revealed a negative correlation between hepatic steatosis and pgRNA (r =  - 0.529, P < 0.001), HBV DNA (r =  - 0.456, P < 0.001), HBsAg (r =  - 0.465, P < 0.001) and HBeAg (r =  - 0.339, P < 0.001) levels; Multivariate logistic regression analysis identified HBV DNA (odds ratio [OR] = 0.283, P < 0.001), HBsAg (OR = 0.300, P < 0.001), and controlled attenuation parameter (CAP) values (OR = 1.013, P = 0.038) as independent factors influencing pgRNA levels below the LLD in patients with CHB.

CONCLUSIONS

This study establishes a negative correlation between hepatic steatosis and hepatitis B virology, demonstrating decreased HBV expression in patients with CHB + MAFLD.

Pharmacological Activation of AMPK Prevents Drp1-mediated Mitochondrial Fission and Alleviates Hepatic Steatosis In vitro

BACKGROUND

The incidence of non-alcoholic fatty liver disease (NAFLD) is increasing worldwide. Adenosine monophosphate-activated protein kinase (AMPK) activation is beneficial for NAFLD treatment. Recent studies show the excessive fission of mitochondria during NAFLD progression, so targeting mitochondria dynamics may be a possible target for NAFLD. Still, little is known about whether AMPK regulates mitochondrial dynamics in hepar.

OBJECTIVE

This study investigated whether AMPK activation alleviates hepatic steatosis by regulating mitochondrial dynamics mediated by GTPase dynamin-related protein 1 (Drp1).

METHODS

Human hepatocyte line L-02 cells were cultured and subjected to palmitic acid (PA) treatment for 24 h to establish a hepatic steatosis model in vitro, which was pre-treated with different tool drugs. Hepatocyte function, hepatocyte lipid content, mitochondrial reactive oxygen species (ROS) production, and mitochondrial membrane potential (MMP) were examined. The expression levels of genes and proteins associated with mitochondrial dynamics were assessed using reverse transcription-quantitative PCR and western blotting.

RESULTS

The results indicated that 5-Aminoimidazole-4-carboxamide 1-β-D-ribofuranoside (AICAR), an AMPK activator, improved hepatocyte function, as demonstrated by decreased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity (P＜0.05 or P＜0.01). In addition, AICAR decreased total cholesterol (TC) and triglyceride (TG) content and lipid deposition in hepatocytes (P＜0.01); decreased ROS production; improved MMP (P＜0.01); reduced fission-1 (Fis1) and mitochondrial fission factor (Mff) mRNA expression; and downregulated p-Drp1 (Ser 616) protein expression. In contrast, AICAR increased mitochondrial fusion factor mitofusin-1 (Mfn1) and mitofusin-2 (Mfn2) mRNA expression and upregulated p-Drp1 (Ser 637) protein expression. Mdivi-1, a Drp-1 inhibitor, was used to confirm whether mitochondrial dynamics regulated by Drp1-mediated the role of AICAR. Similar to AICAR, Mdivi-1 improved hepatocyte function and MMP significantly, decreased ROS production and lipid deposition, downregulated Fis1 and Mff mRNA expression, downregulated p-Drp1 (Ser 616) protein expression, and enhanced Mfn1 and Mfn2 mRNA and p-Drp1 (Ser 637) protein expression. However, Compound C, an AMPKspecific inhibitor, had less impact on the protective effect of Mdivi-1.

CONCLUSION

The results demonstrated that AMPK activation has a protective effect on hepatic steatosis in vitro, largely dependent on the inhibition of Drp1-mediated mitochondrial fission.

Histopathological, physiological, and multi-omics insights into the hepatotoxicity mechanism of nanopolystyrene and/or diclofenac in Mylopharyngodon piceus

Nanopolystyrene (NP) and diclofenac (DCF) are common environmental contaminants in the aquatic ecosystem; therefore, the present study aimed to investigate the hepatotoxicity of NP and/or DCF exposure on aquatic organisms and the underlying mechanisms. Juvenile Mylopharyngodon piceus were used as a model organism to study the effects of NP and/or DCF exposure at environmentally relevant concentrations for 21 days. Subchronic exposure to NP and/or DCF resulted in liver histological damage. In the NP group, the presence of large lipid droplets was observed, whereas the DCF group exhibited marked hepatic sinusoidal dilatation accompanied by inflammation. Additionally, this exposure induced liver oxidative stress, as evidenced by the changes in several physiological parameters, including catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), total antioxidant capacity (T-AOC), reactive oxygen species (ROS), and malondialdehyde (MDA). Integrated transcriptomic and metabolomic analysis was performed to further investigate the molecular mechanism underlying hepatotoxicity. Multi-omics analysis demonstrated, for the first time to our knowledge, that NP induced hepatic steatosis mainly through activating the glycerol-3-phosphate pathway and inhibiting VLDL assembly by targeting several key enzyme genes including GPAT, DGAT, ACSL, APOB, and MTTP. Furthermore, NP exposure disrupted arachidonic acid metabolism, which induced the release of inflammatory factors and inhibited the release of anti-inflammatory factors, ultimately causing liver inflammation in M. piceus. In contrast, DCF induced interleukin production and downregulated KLF2, causing hepatic sinusoidal dilatation with inflammation in juvenile M. piceus, which is consistent with the finding of JAK-STAT signaling pathway activation. In addition, the upregulated AMPK signaling pathway in the DCF group suggested perturbation of energy metabolism. Collectively, these findings provide novel insights into the molecular mechanism of the multiple hepatotoxicity endpoints of NP and/or DCF exposure in aquatic organisms.

The brominated flame retardant tetrabromobisphenol A-bis(2,3-dibromo-2-methylpropyl ether) as well as hexabromocyclododecane lead to lipid disorders in mice

The brominated flame retardant tetrabromobisphenol A-bis(2,3-dibromo-2-methylpropyl ether) (TBBPA-DBMPE) is a recommended substitute for hexabromocyclododecane (HBCD), a banned persistent organic pollutant, yet its potential toxicities remains largely unexplored. Here, we investigated the effects of a long-term exposure to TBBPA-DBMPE at nominal doses of 50 and 1000 μg/kg/d on lipid homeostasis in CD-1 mice, in comparison with 50 μg/kg/d HBCD as a positive control. Male pups received chemical treatments through maternal administration via drinking water from postnatal day 0-21, followed by direct administration through drinking water after weaning. On the 23rd week after treatment, the oral lipid tolerance test revealed that low-dose TBBPA-DBMPE as well as HBCD affected lipid tolerance, although the fasting serum triglyceride (TG) levels were not altered. When chemical treatment was extended to the 32nd week, TBBPA-DBMPE-treated animals displayed adipocyte hypertrophy in both white adipose tissue (eWAT) and brown adipose tissue (BAT) and hepatic steatosis, which was largely consistent with the effects of HBCD. These findings indicate that like HBCD, TBBPA-DBMPE led to increased lipid load in mice. Interestingly, we also observed intestinal histological changes, coupled with increased expression of lipid absorption-related genes in both HBCD and TBBPA-DBMPE treatments, suggesting increased lipid absorption. This was supported by in vitro findings that both HBCD and TBBPA-DBMPE promoted lipid accumulation in IEC-6 cells under the stress of oleic acid for 6 h, implying that altered lipid absorption by the intestine may partly contributed to increased lipid load in mice. Overall, the effects of 50 μg/kg/d TBBPA-DBMPE in terms of some parameters were comparable with 50 μg/kg/d HBCD, suggesting that TBBPA-DBMPE may not be an ideal substitute of HBCD.

Association of insulin resistance indicators with hepatic steatosis and fibrosis in patients with metabolic syndrome

BACKGROUND

To investigate the association of four insulin resistance (IR) indicators with hepatic steatosis and fibrosis in patients with metabolic syndrome (MetS), as well as to compare the diagnostic value of these indicators in identifying hepatic steatosis and fibrosis in individuals with MetS.

METHODS

This cross-sectional study used the data from the National Health and Nutrition Examination Survey 2017-2018. IR indicators included homeostasis model assessment of IR (HOMA-IR), triglyceride/glucose (TyG) index, triglyceride glucose-waist-to-height ratio (TyG-WHtR), and metabolic score for IR (METS-IR). The main endpoints of this study were hepatic steatosis and hepatic fibrosis. Weighted univariate and multivariate logistic regression models were employed to evaluate the association between four IR indicators and both hepatic steatosis, hepatic fibrosis. The efficacy of various IR indicators in the detection of hepatic steatosis and hepatic fibrosis were assessed using receiver operating characteristics curve (ROC).

RESULTS

A total of 876 participants with MetS were enrolled. Among the participants, hepatic steatosis was observed in 587 MetS individuals, while hepatic fibrosis was identified in 151 MetS individuals. In multivariate logistic regression model, HOMA-IR, TyG, TyG-WHtR, and METS-IR were related to the increased odd of hepatic steatosis. Additionally, HOMA-IR, TyG-WHtR, and METS-IR were associated with increased odd of hepatic fibrosis. According to the ROC analysis, the area under the curve (AUC) of the TyG-WHtR (AUC = 0.705, 95%CI: 0.668-0.743) was higher than HOMA-IR (AUC = 0.693, 95%CI: 0.656-0.730), TyG (AUC = 0.627, 95%CI: 0.587-0.666), and METS-IR (AUC = 0.685, 95%CI: 0.648-0.722) for identifying hepatic steatosis of MetS patients. Likewise, TyG-WHtR was also higher than HOMA-IR, TyG, and METS-IR for identifying hepatic fibrosis of MetS patients.

CONCLUSION

HOMA-IR, TyG-WHtR, and METS-IR may be associated with the risk of hepatic steatosis and fibrosis among the U.S. adult population with MetS. In addition, TyG-WHtR may have a good predictive value for hepatic steatosis and hepatic fibrosis.

Fructose-induced perturbation in cellular proteostasis via RPS6KB1 promotes hepatic steatosis

Dietary fructose intake through increased consumption of refined sugar induces hepatic de novo lipogenesis (DNL), a major contributor to hepatic steatosis in NAFLD, however, it's mechanism is not completely understood. Using HepG2 cells, we show that fructose induced DNL involves ribosomal protein S6 kinase B1 (RPS6KB1) driven augmentation of hepatic protein synthesis. This consequently results in endoplasmic reticulum (ER)-stress induced expression of pro-lipogenic gene, fatty acid synthase (FASN). Additionally, the inhibition of fructose induced protein synthesis by either cycloheximide (CHX) or an RPS6KB1 inhibitor significantly reduced both ER-stress and FASN expression. Additionally, corroborating with our in vitro results, the analysis of human NAFLD transcriptomic datasets showed significant upregulation of protein synthesis pathways in the liver of patients with hepatic steatosis, thus linking protein synthesis to lipid accumulation during the early stages of NAFLD. Our results, therefore, demonstrate that RPS6KB1 driven "translation overdrive" coupled with ER-stress contributes to lipogenic gene transcription, and propose RPS6KB1 inhibition as a therapeutic strategy to counter fructose induced hepatic steatosis in NAFLD.

Hepatic steatosis using ultrasound-derived fat fraction: First technical and clinical evaluation

OBJECTIVES

To explore the technical and clinical evaluation of ultrasound-derived fat fraction (UDFF) measurement in adult patients in whom fatty liver was suspected.

MATERIALS AND METHODS

In this prospective study, 41 participants were initially enrolled in our hospital between October 2022 and December 2022 and received UDFF assessment using Siemens ACUSON Sequoia system equipped with DAX transducer. UDFF measurement was performed three times to obtain UDFF values from each imaging location (V hepatic segment and VIII hepatic segment) per participant, and the depth (skin-to-capsule distance) was automatically measured. The echogenicity of liver tissue in B mode ultrasound (BMUS) was compared to the normal kidney tissue, and fatty liver was graded as mild (Grade 1), moderate (Grade 2), and severe (Grade 3). The median of the acquired overall median UDFF values was used for statistical analysis. All ultrasound examinations were performed by one of two radiologists (with 20 and 10 years of liver ultrasound imaging experience).

RESULTS

Finally, UDFF measurement was successfully performed on 38 participants to obtain valid values, including 21 men with a median age of 40.0 years (interquartile range [IQR]: 23.0 - 58.5) and 17 women with a median age of 60.0 years (IQR: 29.5 - 67.0). Fatty liver was diagnosed by BMUS features in 47.4% (18/38) participants. Among all participants, the median UDFF value was 7.0% (IQR: 4.0 - 15.6). A significant difference in UDFF values was found between participants with fatty liver and without fatty liver (U = 7.0, P < 0.001), and UDFF values elevated as the grade of the fatty liver increased (P < 0.001). The median UDFF values from the three UDFF measurements obtained during each ultrasound examination showed excellent agreement (ICC = 0.882 [95% confidence interval: 0.833 - 0.919]). The Spearman correlation of UDFF values in different depths was moderate, with a rs value of 0.546 (P < 0.001). No significant differences in UDFF values were found between V hepatic segment and VIII hepatic segment (U = 684.5, P = 0.697).

CONCLUSIONS

UDFF provides a novel non-invasive imaging tool for hepatic steatosis assessment with excellent feasibility.

A prospective comparison of three ultrasound-based techniques in quantitative diagnosis of hepatic steatosis in NAFLD

PURPOSE

To investigate the correlation between different ultrasound attenuation-based techniques and to compare their diagnostic performances using proton magnetic resonance spectroscopy (1H-MRS) as a reference standard.

METHODS

Participants who had clinical suspicion of nonalcoholic fatty liver disease (NAFLD) were prospectively recruited. Each subject had ultrasound with attenuation imaging (ATI) or quantitative ultrasound including tissue attenuation imaging (TAI) and tissue scatter-distribution imaging (TSI), and controlled-attenuation parameter (CAP) and 1H-MRS if available. The technical success rates, intra-observer repeatabilities of attenuation and backscattering coefficient were evaluated. ATI, TAI and CAP were three attenuation-based techniques. Spearman coefficient was used to test correlations among them and 1H-MRS. In addition, the diagnostic performances of these parameters for detecting ≥ 5% or 10% hepatic steatosis were evaluated.

RESULTS

130 participants had ultrasound scanning. Among them, 67 had CAP and 48 had 1H-MRS. The technical success rates were all 100%. The intra-observer repeatabilities of them were also excellent (ICCs > 0.90) and AC-ATI correlated well with AC-TAI (r = 0.752). AC-ATI, AC-TAI showed moderate correlation with CAP, (rATI = 0.623, 95% CI 0.446-0.752, P < 0.001; rTAI = 0.573, 95% CI 0.377-0.720, P < 0.001). For correlation with 1H-MRS, ATI and TAI performed better than CAP(rATI = 0.587; rTAI = 0.712; r CAP = 0.485). The AUCs of ATI, TAI, TSI and CAP for detecting ≥ 5% hepatic steatosis were 0.883, 0.862, 0.870 and 0.868, respectively. The AUC improved to 0.907 when TAI and TSI were combined (P < 0.05). When detecting ≥ 10% hepatic steatosis, the AUCs were 0.855, 0.702, 0.822 and 0.838, respectively.

CONCLUSION

Different ultrasound attenuation-based techniques were well correlated and exhibited good diagnostic performances in quantitative diagnosis of hepatic steatosis, however, the threshold values were different. Combinations of multiple parameters may improve the diagnostic performance in detecting hepatic steatosis.

TRIAL REGISTRATION

The study has been registered online ( https://www.chictr.org.cn ; unique identifier: ChiCTR2300069459).