Metabolic-associated fatty liver disease: New nomenclature and approach with hot debate

Metabolic dysfunction-associated fatty liver disease and risks of incident coronary artery disease and cerebrovascular disease: LIFE Study

AIM

To estimate the risks of coronary artery and cerebrovascular diseases in metabolic dysfunction-associated fatty liver disease (MAFLD) using different fatty liver index (FLI) cut-off values in a Japanese population.

METHODS

We analyzed insurance claims and health checkup data from public medical insurance enrollees aged ≥40 years in seven Japanese municipalities who had undergone a health checkup between April 2015 and March 2022. The MAFLD cases were identified as hepatic steatosis (defined as FLI ≥60 or ≥37) with overweight/obesity, diabetes, or lean/normal weight with metabolic dysregulation. Cox proportional hazards models estimated adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for MAFLD (reference: non-MAFLD) regarding incident coronary artery and cerebrovascular diseases. Covariates included age, sex, smoking habit, low-density lipoprotein cholesterol level, and statin use.

RESULTS

The study was undertaken using 163 834 individuals. The HRs of MAFLD for coronary artery disease were 1.44 (95% CI, 1.24-1.67) for FLI ≥ 60 and 1.49 (95% CI, 1.32-1.68) for FLI ≥ 37. The HRs of MAFLD for cerebrovascular disease were 1.58 (95% CI, 1.22-2.05) for FLI ≥ 60 and 1.41 (95% CI, 1.15-1.74) for FLI ≥ 37. In women, neither FLI cut-off was associated with coronary artery disease, and only FLI ≥ 60 was associated with cerebrovascular disease.

CONCLUSIONS

The MAFLD cases identified using the two FLI cut-off values were at higher risk for coronary artery and cerebrovascular diseases. Asian-specific FLI cut-offs may better identify hepatic steatosis in Japan than Western-specific cut-offs, but there is a need to consider sex differences when determining at-risk subgroups for targeted health interventions.

Parallel randomised trial testing community fibrosis assessment for suspected non-alcoholic fatty liver disease: outcomes from LOCATE-NAFLD

OBJECTIVE

Non-alcoholic fatty liver disease (NAFLD) is estimated to affect a third of Australian adults, and its prevalence is predicted to rise, increasing the burden on the healthcare system. The LOCal Assessment and Triage Evaluation of Non-Alcoholic Fatty Liver Disease (LOCATE-NAFLD) trialled a community-based fibrosis assessment service using FibroScan to reduce the time to diagnosis of high-risk NAFLD and improve patient outcomes.

METHODS

We conducted a 1:1 parallel randomised trial to compare two alternative models of care for NAFLD diagnosis and assessment. Participants had suspected NAFLD and were referred to a hepatology clinic in one of three major hospitals in South-East Queensland. Eligible consenting participants were randomised to receive usual care or the intervention (LOCATE). Participants in the intervention arm received a FibroScan outside of the hospital setting, with results provided to their primary care provider and the referring hepatologist. All participants were followed up 12 months after randomisation to measure their clinical and patient-reported outcomes.

RESULTS

97 participants were recruited from October 2020 to December 2022. Of the 50 participants randomised to the intervention arm, one failed to attend their appointment, and of the 48 (98%) who had a FibroScan 13 (27%) had a liver stiffness measurement of 8.0 kPa or greater. The HR for the time to diagnosis of high risk was 1.28 (95% CI 0.59 to 2.79), indicating a faster average time to diagnosis with the intervention, but failing to conclusively demonstrate a faster time. The intervention did greatly reduce the time to FibroScan by almost 1 year (median difference 0.92 years, 95% CI 0.56 to 1.45). Other clinical outcomes showed minimal changes.

CONCLUSION

The LOCATE model shows potential for impact, particularly in reducing waiting times for patients at high risk of developing severe liver disease due to NAFLD. A larger sample and longer follow-ups are needed to measure additional clinical outcomes.

TRIAL REGISTRATION NUMBER

ACTRN12620000158965.

Long-Term Aerobic Exercise Enhances Hepatoprotection in MAFLD by Modulating Exosomal miR-324 via ROCK1

BACKGROUND

Insulin resistance (IR) is central to the progression of non-alcoholic fatty liver disease (MAFLD). While aerobic exercise reduces hepatic fat and enhances insulin sensitivity, the specific mechanisms-particularly those involving exosomal pathways-are not fully elucidated.

METHOD

Exosomes were isolated from 15 MAFLD patients' plasma following the final session of a 12-week aerobic exercise intervention. Liver fat content was measured using MRI-PDFF, and metabolic parameters were assessed via OGTT, HOMA-IR, QUICKI, and VO2 max. Co-culture experiments evaluated the effects of exercise-derived exosomes on IR signaling pathways. miRNA microarray analysis identified miR-324, which was quantified in high-fat diet (HFD) mice with and without exercise and compared between athletes and sedentary controls. Functional assays assessed miR-324's role in glucose and lipid metabolism, while luciferase reporter and Western blot assays confirmed ROCK1 as its direct target.

RESULT

Aerobic exercise significantly reduced liver fat and improved insulin sensitivity in both MAFLD patients and HFD mice. Notably, exosomal miR-324 levels were lower in athletes than sedentary controls, indicating an inverse association with insulin sensitivity. Post-exercise, precursor and mature miR-324 increased in adipose tissue and decreased in muscle, suggesting its adipose origin and inverse regulation. Functional assays demonstrated that miR-324 modulates insulin resistance by targeting ROCK1.

CONCLUSION

Exercise-induced exosomal miR-324 from adipose tissue targets ROCK1, revealing a novel mechanism by which aerobic exercise confers hepatoprotection against insulin resistance in MAFLD. These findings enhance our understanding of how exercise influences metabolic health and may inform future therapeutic strategies for managing MAFLD and related conditions.

Higher Adherence to the Mediterranean Diet Is Associated with a Lower Risk of Steatotic, Alcohol-Related, and Metabolic Dysfunction-Associated Steatotic Liver Disease: A Retrospective Analysis

BACKGROUND AND AIMS

Metabolic liver disease is associated with obesity, insulin resistance, cardiovascular disease, and metabolic disorders. A Mediterranean diet (MD), known for its anti-inflammatory and antioxidant properties, is effective in managing various chronic diseases, including liver diseases. This study aimed to explore the influence of adherence to the MD on the risk of chronic metabolic diseases, including steatotic liver disease (SLD), metabolic dysfunction-associated steatotic liver disease (MASLD), and alcohol-related liver diseases (ALDs).

METHODS

This retrospective cohort study analyzed 5395 individuals from a single center between 2020 and 2022, grouped by adherence to the MD using the Korean Mediterranean Diet Adherence Score (K-MEDAS). MASLD score, ALD, and cardiovascular risk factors were also assessed. Statistical analyses were performed using 1:1 exact matching and multiple regression to compare the less adherent (K-MEDAS 0-7) and highly adherent (K-MEDAS 8-13) groups.

RESULTS

Adjusting for confounding variables, high adherence to the MD was significantly associated with lower rates of SLD (odds ratio [OR] 0.818, 95% confidence interval [CI] 0.700-0.957, p = 0.012), MASLD (OR 0.839, 95% CI 0.714-0.986, p = 0.033), and ALD (OR 0.677, 95% CI 0.671-0.683, p < 0.001). Post-propensity score matching analysis revealed that the highly adherent group exhibited significantly lower triglyceride levels, triglyceride and glucose index, atherogenic Index of Plasma, and Framingham risk scores than the less adherent group.

CONCLUSIONS

Good adherence to the MD considerably reduces the risk of SLD, MASLD, and ALD, underscoring its protective effects and potential to prevent metabolic liver diseases and their complications.

Glucoraphanin and sulforaphane mitigate TNFα-induced Caco-2 monolayers permeabilization and inflammation

Intestinal permeabilization is central to the pathophysiology of chronic gut inflammation. This study investigated the efficacy of glucoraphanin (GR), prevalent in cruciferous vegetables, particularly broccoli, and its derivative sulforaphane (SF), in inhibiting tumor necrosis factor alpha (TNFα)-induced Caco-2 cell monolayers inflammation and permeabilization through the regulation of redox-sensitive events. TNFα binding to its receptor led to a rapid increase in oxidant production and subsequent elevation in the mRNA levels of NOX1, NOX4, and Duox2. GR and SF dose-dependently mitigated both these short- and long-term alterations in redox homeostasis. Downstream, GR and SF inhibited the activation of the redox-sensitive signaling cascades NF-κB (p65 and IKK) and MAPK ERK1/2, which contribute to inflammation and barrier permeabilization. GR (1 μM) and SF (0.5-1 μM) prevented TNFα-induced monolayer permeabilization and the associated reduction in the levels of the tight junction (TJ) proteins occludin and ZO-1. Both GR and SF also mitigated TNFα-induced increased mRNA levels of the myosin light chain kinase, which promotes TJ opening. Molecular docking suggests that although GR is mostly not absorbed, it could interact with extracellular and membrane sites in NOX1. Inhibition of NOX1 activity by GR would mitigate TNFα receptor downstream signaling and associated events. These findings support the concept that not only SF, but also GR, could exert systemic health benefits by protecting the intestinal barrier against inflammation-induced permeabilization, in part by regulating redox-sensitive pathways. GR has heretofore not been viewed as a biologically active molecule, but rather, the benign precursor of highly active SF. The consumption of GR and/or SF-rich vegetables or supplements in the diet may offer a means to mitigate the detrimental consequences of intestinal permeabilization, not only in disease states but also in conditions characterized by chronic inflammation of dietary and lifestyle origin.

Epidemiology and diagnosis of metabolic dysfunction-associated fatty liver disease

The most common chronic liver illness worldwide is metabolic dysfunction linked to fatty liver disease (MAFLD), which is poorly understood by doctors and patients. Many people with this disease develop steatohepatitis, cirrhosis and its consequences, as well as extrahepatic manifestations; these conditions are particularly common if they are linked to diabetes mellitus or obesity. A breakthrough with numerous benefits is the switch from NAFLD to MAFLD in terms of terminology and methodology. The diagnosis of MAFLD is based on affirmative criteria; unlike NAFLD, it is no longer based on exclusion. The diagnosis of MAFLD and the evaluation of steatosis and fibrosis is achieved using liver biopsy and non-invasive laboratory or radiographic techniques. We briefly address the most recent developments in MAFLD epidemiology and diagnosis.

Beneficial Effects of the Ketogenic Diet on Nonalcoholic Fatty Liver Disease (NAFLD/MAFLD)

The prevalence of nonalcoholic fatty liver disease (NAFLD) is likely to be approaching 38% of the world's population. It is predicted to become worse and is the main cause of morbidity and mortality due to hepatic pathologies. It is particularly worrying that NAFLD is increasingly diagnosed in children and is closely related, among other conditions, to insulin resistance and metabolic syndrome. Against this background is the concern that the awareness of patients with NAFLD is low; in one study, almost 96% of adult patients with NAFLD in the USA were not aware of their disease. Thus, studies on the therapeutic tools used to treat NAFLD are extremely important. One promising treatment is a well-formulated ketogenic diet (KD). The aim of this paper is to present a review of the available publications and the current state of knowledge of the effect of the KD on NAFLD. This paper includes characteristics of the key factors (from the point of view of NAFLD regression), on which ketogenic diet exerts its effects, i.e., reduction in insulin resistance and body weight, elimination of fructose and monosaccharides, limitation of the total carbohydrate intake, anti-inflammatory ketosis state, or modulation of gut microbiome and metabolome. In the context of the evidence for the effectiveness of the KD in the regression of NAFLD, this paper also suggests the important role of taking responsibility for one's own health through increasing self-monitoring and self-education.

NAFLD (MASLD)/NASH (MASH): Does It Bother to Label at All? A Comprehensive Narrative Review

Nonalcoholic fatty liver disease (NAFLD), or metabolic dysfunction-associated steatotic liver disease (MASLD), is a liver condition that is linked to overweight, obesity, diabetes mellitus, and metabolic syndrome. Nonalcoholic steatohepatitis (NASH), or metabolic dysfunction-associated steatohepatitis (MASH), is a form of NAFLD/MASLD that progresses over time. While steatosis is a prominent histological characteristic and recognizable grossly and microscopically, liver biopsies of individuals with NASH/MASH may exhibit several other abnormalities, such as mononuclear inflammation in the portal and lobular regions, hepatocellular damage characterized by ballooning and programmed cell death (apoptosis), misfolded hepatocytic protein inclusions (Mallory-Denk bodies, MDBs), megamitochondria as hyaline inclusions, and fibrosis. Ballooning hepatocellular damage remains the defining feature of NASH/MASH. The fibrosis pattern is characterized by the initial expression of perisinusoidal fibrosis ("chicken wire") and fibrosis surrounding the central veins. Children may have an alternative form of progressive NAFLD/MASLD characterized by steatosis, inflammation, and fibrosis, mainly in Rappaport zone 1 of the liver acinus. To identify, synthesize, and analyze the scientific knowledge produced regarding the implications of using a score for evaluating NAFLD/MASLD in a comprehensive narrative review. The search for articles was conducted between 1 January 2000 and 31 December 2023, on the PubMed/MEDLINE, Scopus, Web of Science, and Cochrane databases. This search was complemented by a gray search, including internet browsers (e.g., Google) and textbooks. The following research question guided the study: "What are the basic data on using a score for evaluating NAFLD/MASLD?" All stages of the selection process were carried out by the single author. Of the 1783 articles found, 75 were included in the sample for analysis, which was implemented with an additional 25 articles from references and gray literature. The studies analyzed indicated the beneficial effects of scoring liver biopsies. Although similarity between alcoholic steatohepatitis (ASH) and NASH/MASH occurs, some patterns of hepatocellular damage seen in alcoholic disease of the liver do not happen in NASH/MASH, including cholestatic featuring steatohepatitis, alcoholic foamy degeneration, and sclerosing predominant hyaline necrosis. Generally, neutrophilic-rich cellular infiltrates, prominent hyaline inclusions and MDBs, cholestasis, and obvious pericellular sinusoidal fibrosis should favor the diagnosis of alcohol-induced hepatocellular injury over NASH/MASH. Multiple grading and staging methods are available for implementation in investigations and clinical trials, each possessing merits and drawbacks. The systems primarily used are the Brunt, the NASH CRN (NASH Clinical Research Network), and the SAF (steatosis, activity, and fibrosis) systems. Clinical investigations have utilized several approaches to link laboratory and demographic observations with histology findings with optimal platforms for clinical trials of rapidly commercialized drugs. It is promising that machine learning procedures (artificial intelligence) may be critical for developing new platforms to evaluate the benefits of current and future drug formulations.

Lack of awareness and ethnic polarity is a major cause of metabolic associated fatty liver disease in high-risk diabetes population in South London

BACKGROUND

Metabolic associated fatty liver disease (MAFLD) stands as the leading cause of chronic liver disease globally. Notably, individuals with metabolic risk factors, such as diabetes and obesity, exhibit a staggering prevalence of MAFLD, with estimates reaching up to 70%. However, despite its widespread occurrence, there's a noticeable gap in understanding and awareness about MAFLD among these high-risk groups.

OBJECTIVES

The main objective of this study was to assess the awareness and prevalence of MAFLD among diabetic patients who regularly receive secondary care focusing particularly on how multiethnic backgrounds and associated lifestyle preferences influence these health outcomes.

DESIGN

Cross-sectional study.

METHODS

Patients with type 2 diabetes (T2D) who regularly attend Lambeth Diabetes Intermediate Care Team clinics were invited to undergo MAFLD screening using FibroScan. Those who agreed to participate were provided with structured questionnaires on diet, physical activity, and MAFLD knowledge by a hepatologist. For each participant, anthropometric data, medical history, liver stiffness measurement, and controlled attenuation parameter (CAP) were documented. Steatosis was identified with a CAP value of ⩾275 dB/m, and advanced fibrosis was flagged at values of ⩾8 kPa.

RESULTS

The FibroScan data was valid in 96.4% (215), 53.5% (115/215) had steatosis and 26.2% (58/215) had liver fibrosis in this multiethnic high-risk group. Awareness of MAFLD was notably low at 30.9%. Alarmingly, 69% of patients diagnosed with liver fibrosis were unfamiliar with the condition. Additionally, understanding of MAFLD showed variation among different ethnic groups with highest levels were demonstrated in the Caucasian/White population (46%). Majority (96%) of these subjects were receiving specific lifestyle advice from healthcare professionals due to metabolic conditions and comorbidities. However, most patients preferred diets that were rich in carbohydrates (65.8%) and only 43% subjects performed moderate exercise daily highlighting lack of understanding regarding MAFLD and lifestyle management.

CONCLUSION

There's a pressing need for increased awareness of MAFLD, especially in multiethnic high-risk groups. Additionally, the development of cost-effective strategies to stratify risk is essential to address this growing health concern.

Proinflammatory interleukins 2, 6 and tumor necrosis factor alpha in patients with hypertension and diabetes mellitus depending on the presence of metabolic-associated liver steatosis

Background. Lack of information about proinflammatory interleukins (IL) and tumor necrosis factor alpha (TNFα) levels in case of metabolic-associated liver steatosis (MALS) and their roles in its progression to steatohepatitis are key reasons for the relevance and actuality of our study. The purpose: to evaluate proinflammatory interleukins 2, 6, and TNFα levels in concomitant liver steatosis. Materials and methods. Thirty-five patients with hypertension stage II–III, type 2 diabetes mellitus were examined. All of them were treated on an outpatient basis according to the guidelines of the Ministry of Health of Ukraine and the Declaration of Helsinki. Participants were divided into the main group with MALS (n = 24, males 45.8 %, females 54.2 %; average age 55.83 ± 0.89 years) and the control group without steatosis (n = 11, males 54.5 %, females 45.5 %; average age 53.00 ± 1.55 years). In addition to standard parameters, levels of IL6, IL2, TNFα, selectin, resistin, insulin, C-peptide, glycated hemoglobin, non-esterified fatty acids were evaluated, and some indexes were calculated, including triglyceride-glucose index and Castelli indexes I and II. Results were processed statistically, with significance level of р < 0.05. Results. Although MALS is not followed by qualitative differences in proinflammatory IL2, IL6 and TNFα compared to no steatosis, the risk of TNFα elevation was 5 times higher in patients with MALS (odds ratio 5.08; 95% confidence interval 1.02–25.17). An increase in IL2 and TNFα is unfavorable for patients with MALS, it can be considered as a marker of steatosis progression to steatohepatitis, as it is associated with transaminase activation, endogenous intoxication, lipid distress and glucose intolerance. IL6 was rather lower in patients with MALS compared to those without steatosis, but its growth was exponential and proceeded simultaneously to IL2 and TNFα. Conclusions. MALS was not associated with significant changes in IL2, IL6 and TNFα compared to no steatosis, but their elevation can be criteria for transformation into steatohepatitis due to the activation of transaminases, inflammation, endogenous intoxication, lipid distress, glucose intolerance.

Cardiovascular morbidity and mortality in lean vs. non-lean MASLD: A comprehensive meta-analysis

BACKGROUND

Lean metabolic dysfunction-associated steatotic liver disease (MASLD), characterized by a BMI < 25 kg/m² (or < 23 kg/m² in Asians), presents a challenging prognosis compared to non-lean MASLD. This study examines cardiovascular outcomes in both lean and non-lean MASLD cohorts.

METHODS

In this meta-analysis, pooled odds ratios (ORs) within 95 % confidence intervals (CIs) were calculated for primary outcomes (cardiovascular mortality and major adverse cardiovascular events [MACE]) and secondary outcomes (cardiovascular disease [CVD], all-cause mortality, hypertension, and dyslipidemia). Studies comparing lean and non-lean MASLD within the same cohorts were analyzed, prioritizing those with larger sample sizes or recent publication dates.

RESULTS

Twenty-one studies were identified, encompassing lean MASLD patients (n = 7153; mean age 52.9 ± 7.4; 56 % male) and non-lean MASLD patients (n = 23,514; mean age 53.2 ± 6.8; 63 % male). Lean MASLD exhibited a 50 % increase in cardiovascular mortality odds compared to non-lean MASLD (OR: 1.5, 95 % CI 1.2-1.8; p < 0.0001). MACE odds were 10 % lower in lean MASLD (OR: 0.9, 95 % CI 0.7-1.2; p = 0.7), while CVD odds were 40 % lower (p = 0.01). All-cause mortality showed a 40 % higher odds in lean MASLD versus non-lean MASLD (p = 0.06). Lean MASLD had 30 % lower odds for both hypertension (p = 0.01) and dyslipidemia (p = 0.02) compared to non-lean MASLD.

CONCLUSION

Despite a favorable cardiometabolic profile and comparable MACE rates, lean individuals with MASLD face elevated cardiovascular mortality risk.

Overnutrition, Hyperinsulinemia and Ectopic Fat: It Is Time for A Paradigm Shift in the Management of Type 2 Diabetes

The worldwide incidence of prediabetes/type 2 has continued to rise the last 40 years. In the same period, the mean daily energy intake has increased, and the quality of food has significantly changed. The chronic exposure of pancreatic β-cells to calorie excess (excessive energy intake) and food additives may increase pancreatic insulin secretion, decrease insulin pulses and/or reduce hepatic insulin clearance, thereby causing chronic hyperinsulinemia and peripheral insulin resistance. Chronic calorie excess and hyperinsulinemia may promote lipogenesis, inhibit lipolysis and increase lipid storage in adipocytes. In addition, calorie excess and hyperinsulinemia can induce insulin resistance and contribute to progressive and excessive ectopic fat accumulation in the liver and pancreas by the conversion of excess calories into fat. The personal fat threshold hypothesis proposes that in susceptible individuals, excessive ectopic fat accumulation may eventually lead to hepatic insulin receptor resistance, the loss of pancreatic insulin secretion, hyperglycemia and the development of frank type 2 diabetes. Thus, type 2 diabetes seems (partly) to be caused by hyperinsulinemia-induced excess ectopic fat accumulation in the liver and pancreas. Increasing evidence further shows that interventions (hypocaloric diet and/or bariatric surgery), which remove ectopic fat in the liver and pancreas by introducing a negative energy balance, can normalize insulin secretion and glucose tolerance and induce the sustained biochemical remission of type 2 diabetes. This pathophysiological insight may have major implications and may cause a paradigm shift in the management of type 2 diabetes: avoiding/reducing ectopic fat accumulation in the liver and pancreas may both be essential to prevent and cure type 2 diabetes.

Metabolic-associated fatty liver disease: a selective review of pathogenesis, diagnostic approaches, and therapeutic strategies

Background

Metabolic associated fatty liver disease (MAFLD) is a novel terminology introduced in 2020 to provide a more accurate description of fatty liver disease associated with metabolic dysfunction. It replaces the outdated term nonalcoholic fatty liver disease (NAFLD) and aims to improve diagnostic criteria and tailored treatment strategies for the disease. NAFLD, the most prevalent liver disease in western industrialized nations, has been steadily increasing in prevalence and is associated with serious complications such as cirrhosis and hepatocellular carcinoma. It is also linked to insulin resistance syndrome and cardiovascular diseases. However, current studies on NAFLD have limitations in meeting necessary histological endpoints.

Objective

This literature review aims to consolidate recent knowledge and discoveries concerning MAFLD, integrating the diverse aspects of the disease. Specifically, it focuses on analyzing the diagnostic criteria for MAFLD, differentiating it from NAFLD and alcoholic fatty liver disease (AFLD), and exploring the epidemiology, clinical manifestations, pathogenesis, and management approaches associated with MAFLD. The review also explores the associations between MAFLD and other conditions. It discusses the heightened mortality risk associated with MAFLD and its link to chronic kidney disease (CKD), showing that MAFLD exhibits enhanced diagnostic accuracy for identifying patients with CKD compared to NAFLD. The association between MAFLD and incident/prevalent CKD is supported by cohort studies and meta-analyses.

Conclusion

This literature review highlights the importance of MAFLD as a distinct terminology for fatty liver disease associated with metabolic dysfunction. The review provides insights into the diagnostic criteria, associations with CKD, and management approaches for MAFLD. Further research is needed to develop more accurate diagnostic tools for advanced fibrosis in MAFLD and to explore the underlying mechanisms linking MAFLD with other conditions. This review serves as a valuable resource for researchers and healthcare professionals seeking a comprehensive understanding of MAFLD.

Detection of Moderate Hepatic Steatosis on Portal Venous Phase Contrast-Enhanced CT: Evaluation Using an Automated Artificial Intelligence Tool

BACKGROUND. Precontrast CT is an established means of evaluating for hepatic steatosis; postcontrast CT has historically been limited for this purpose. OBJECTIVE. The purpose of this study was to evaluate the diagnostic performance of portal venous phase postcontrast CT in detecting at least moderate hepatic steatosis using liver and spleen attenuation measurements determined by an automated artificial intelligence (AI) tool. METHODS. This retrospective study included 2917 patients (1381 men, 1536 women; mean age, 56.8 years) who underwent a CT examination that included at least two series through the liver. Examinations were obtained from an AI vendor's data lake of data from 24 centers in one U.S. health care network and 29 centers in one Israeli health care network. An automated deep learning tool extracted liver and spleen attenuation measurements. The reference for at least moderate steatosis was precontrast liver attenuation of less than 40 HU (i.e., estimated liver fat > 15%). A radiologist manually reviewed examinations with outlier AI results to confirm portal venous timing and identify issues impacting attenuation measurements. RESULTS. After outlier review, analysis included 2777 patients with portal venous phase images. Prevalence of at least moderate steatosis was 13.9% (387/2777). Patients without and with at least moderate steatosis, respectively, had mean postcontrast liver attenuation of 104.5 ± 18.1 (SD) HU and 67.1 ± 18.6 HU (p < .001); a mean difference in postcontrast attenuation between the liver and the spleen (hereafter, postcontrast liver-spleen attenuation difference) of -7.6 ± 16.4 (SD) HU and -31.8 ± 20.3 HU (p < .001); and mean liver enhancement of 49.3 ± 15.9 (SD) HU versus 38.6 ± 13.6 HU (p < .001). Diagnostic performance for the detection of at least moderate steatosis was higher for postcontrast liver attenuation (AUC = 0.938) than for the postcontrast liver-spleen attenuation difference (AUC = 0.832) (p < .001). For detection of at least moderate steatosis, postcontrast liver attenuation had sensitivity and specificity of 77.8% and 93.2%, respectively, at less than 80 HU and 90.5% and 78.4%, respectively, at less than 90 HU; the postcontrast liver-spleen attenuation difference had sensitivity and specificity of 71.4% and 79.3%, respectively, at less than -20 HU and 87.0% and 62.1%, respectively, at less than -10 HU. CONCLUSION. Postcontrast liver attenuation outperformed the postcontrast liver-spleen attenuation difference for detecting at least moderate steatosis in a heterogeneous patient sample, as evaluated using an automated AI tool. Splenic attenuation likely is not needed to assess for at least moderate steatosis on postcontrast images. CLINICAL IMPACT. The technique could promote early detection of clinically significant nonalcoholic fatty liver disease through individualized or large-scale opportunistic evaluation.

Cross-talk between gut microbiota and liver steatosis: Complications and therapeutic target

Liver steatosis is the most widespread chronic liver condition. Its global incidence is rising swiftly and is currently estimated to be 24%. Liver steatosis is strongly related with numerous metabolic syndrome characteristics, like obesity, insulin resistance, hyperlipidemia, and hypertension. The gastrointestinal tract contains about 100 trillion commensal organisms and more than 7,000 distinct bacterial strains. Fat deposition in the liver without secondary causes is known as liver steatosis. Dysregulation of the gut flora is one of the factors connected to the onset of fatty liver disease. Dietary choices may alter constitution of the microbiome and cause gut microbiome dysbiosis, particularly due to the intake of food high in fructose sugars, animal products, and saturated fats. Various gut bacteria cause nutrient metabolism in multiple ways, setting off different inflammatory cascades that encourage liver disease and pathways that help fat build up in the liver. Due to their relatively stable nature, genetic factors may not be responsible for the constant increase in liver steatosis incidence. Genetic factors set the stage for liver steatosis pathogenesis. This review will offer an overview of our present knowledge of the roles played by gut microbiota in regulating the development of liver steatosis, potential side effects, and potential treatment targets.

Visceral Obesity and Cytokeratin-18 Antigens as Early Biomarkers of Liver Damage

Visceral obesity is linked to the progression of fatty liver to nonalcoholic steatohepatitis (NASH). Cytokeratin-18 (CK18) epitopes M30 (CK18M30) and M65 (CK18M65) represent accurate markers for detecting NASH. The aim of this study was to evaluate the association of CK18M30 and CK18M65 levels with anthropometric and metabolic characteristics, liver stiffness, and liver indices of steatosis and fibrosis in a cohort of subjects with visceral obesity; in this cross-sectional study, transient elastography (TE-Fibroscan^®), anthropometric measurements, metabolic parameters, High Sensitivity C-Reactive Protein (hsCRP), and CK18M30 and CK18M65 levels (Apoptosense ELISA, PEVIVA, Germany) were evaluated. Fatty Liver Index (FLI), Fibrosis 4 (FIB-4), and Aspartate transaminase (AST)-platelet ratio index (APRI) were calculated; among 48 subjects, 47.2% presented metabolic syndrome, 93.8% hepatic steatosis, 60.4% high liver stiffness, and 14.6% hypertransminasemia, while FIB-4 and APRI were normal. CK18M30 and CK18M65 levels were significantly correlated with waist circumference, AST, ALT, HoMA-IR, liver stiffness, and APRI (p < 0.001). Subjects with CK18 fragments above the median values showed significantly higher waist circumference, HbA1c, AST, ALT, HoMA-IR, FLI, and APRI compared to those with values below the median; CK18M30 and CK18M65 levels correlated well with anthropometric and metabolic characteristics, representing good biomarkers for early identification of NASH in subjects with visceral obesity.