NASH and atherosclerosis are two aspects of a shared disease: Central role for macrophages

CXCL9, IL2RB, and SPP1, potential diagnostic biomarkers in the co-morbidity pattern of atherosclerosis and non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH) is a hepatocyte inflammation based on hepatocellular steatosis, yet there is no effective drug treatment. Atherosclerosis (AS) is caused by lipid deposition in the endothelium, which can lead to various cardiovascular diseases. NASH and AS share common risk factors, and NASH can also elevate the risk of AS, causing a higher morbidity and mortality rate for atherosclerotic heart disease. Therefore, timely detection and diagnosis of NASH and AS are particularly important. In this study, differential gene expression analysis and weighted gene co-expression network analysis were performed on the AS (GSE100927) and NASH (GSE89632) datasets to obtain common crosstalk genes, respectively. Then, candidate Hub genes were screened using four topological algorithms and externally validated in the GSE43292 and GSE63067 datasets to obtain Hub genes. Furthermore, immune infiltration analysis and gene set variation analysis were performed on the Hub genes to explore the underlying mechanisms. The DGIbd database was used to screen candidate drugs for AS and NASH. Finally, a NASH model was constructed using free fatty acid-induced human L02 cells, an AS model was constructed using lipopolysaccharide-induced HUVECs, and a co-morbidity model was constructed using L02 cells and HUVECs to verify Hub gene expression. The result showed that a total of 113 genes common to both AS and NASH were identified as crosstalk genes, and enrichment analysis indicated that these genes were mainly involved in the regulation of immune and metabolism-related pathways. 28 candidate Hub genes were screened according to four topological algorithms, and CXCL9, IL2RB, and SPP1 were identified as Hub genes after in vitro experiments and external dataset validation. The ROC curves and SVM modeling demonstrated the good diagnostic efficacy of these three Hub genes. In addition, the Hub genes are strongly associated with immune cell infiltration, especially macrophages and γ-δ T cell infiltration. Finally, five potential therapeutic drugs were identified. has-miR-185 and hsa-miR-335 were closely related to AS and NASH. This study demonstrates that CXCL9, IL2RB, and SPP1 may serve as potential biomarkers for the diagnosis of the co-morbidity patterns of AS and NASH and as potential targets for drug therapy.

Cumulative exposure to AHA Life's Essential 8 is associated with nonalcoholic fatty liver disease: a large cohort study

BACKGROUND AND AIM

We aimed to explore the associations of baseline and cumulative cardiovascular health with nonalcoholic fatty liver disease (NAFLD) development and regression using the new Life's Essential 8 score.

METHODS

From a health screening database, participants who underwent at least 4 health examinations between 2012 and 2022 were recruited and categorized into two cohorts: (a) the NAFLD development cohort with no history of NAFLD prior to Exam 4 and (b) the NAFLD regression cohort with diagnosed NAFLD prior to Exam 4. The LE8 score was calculated from each component. The outcomes were defined as newly incident NAFLD or regression of existing NAFLD from Exam 4 to the end of follow-up.

RESULTS

In the NAFLD development cohort, of 21,844 participants, 3,510 experienced incident NAFLD over a median follow-up of 2.3 years. Compared with the lowest quartile of cumulative LE8, individuals in the highest quartile conferred statistically significant 76% lower odds (hazard ratio [HR] 0.24, 95% confidence interval [CI], 0.21-0.28) of NAFLD incidence, and corresponding values for baseline LE8 were 42% (HR 0.58, 95% CI 0.53-0.65). In the NAFLD regression cohort, of 6,566 participants, 469 experienced NAFLD regression over a median follow-up of 2.4 years. Subjects with the highest quartile of cumulative LE8 had 2.03-fold (95% CI, 1.51-2.74) higher odds of NAFLD regression, and corresponding values for baseline LE8 were 1.61-fold (95% CI, 1.24-2.10).

CONCLUSION

Cumulative ideal cardiovascular health exposure is associated with reduced NAFLD development and increased NAFLD regression. Improving and preserving health behaviors and factors should be emphasized as an important part of NAFLD prevention and intervention strategies.

Two sides of the same coin: Non-alcoholic fatty liver disease and atherosclerosis

The prevalence of non-alcoholic fatty liver disease (NAFLD) and atherosclerosis remain high, which is primarily due to widespread adoption of a western diet and sedentary lifestyle. NAFLD, together with advanced forms of this disease such as non-alcoholic steatohepatitis (NASH) and cirrhosis, are closely associated with atherosclerotic-cardiovascular disease (ASCVD). In this review, we discussed the association between NAFLD and atherosclerosis and expounded on the common molecular biomarkers underpinning the pathogenesis of both NAFLD and atherosclerosis. Furthermore, we have summarized the mode of function and potential clinical utility of existing drugs in the context of these diseases.

Association of nonalcoholic fatty liver disease and carotid media-intima thickness: A systematic review and a meta-analysis

Introduction

The relationship between cardiovascular disorders and nonalcoholic fatty liver disease (NAFLD) has been extensively studied. To better pool this data and make a more definite conclusion, we performed a meta-analysis to evaluate the association between NAFLD and the thickness of media and intima of carotid artery (CIMT) and cardiovascular disorders.

Methods

We searched PubMed, Ovid, Scopus, ProQuest, Web of Science, and the Cochrane Library, and analyzed the pooled data using R studio and the "metafor" package.

Results

The final analysis included a total of 59 studies with 16,179 cases and 26,120 control individuals. NAFLD was shown to be associated with an increase of 0.1231 mm (20.6%) in carotid artery intima-media thickness (CIMT) (p = 0.002, 95% confidence interval [CI]: 0.0462-0.2000) in individuals with NAFLD. The prevalence of atherosclerotic plaques in the carotid arteries and the occurrence of NAFLD are significantly correlated, according to a meta-analysis based on 17 distinct studies (p = 0.001, 1.28-1.43, 95% CI, odds ratio = 1.356).

Conclusion

Patients with increased CIMT are considerably more likely to have NAFLD. Large prospective investigations are required to corroborate these findings and their prognostic significance, along with the effectiveness of the available interventions.

Transition patterns of metabolic dysfunction-associated fatty liver disease status in relation to arterial stiffness progression: a health check-up cohort study

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a new diagnostic criterion based on hepatic steatosis and metabolic dysfunction. However, a comprehensive evaluation of the association of MAFLD dynamic transitions with arterial stiffness progression has yet to be conducted. This cohort study included 8807 Chinese health check-up participants (median follow-up = 50.2 months). Participants were categorized into four groups according to MAFLD status at baseline and follow-up (none, persistent, developed and regressed). Arterial stiffness progression was assessed by the annual brachial-ankle pulse wave velocity (ba-PWV) increase and arterial stiffness incidence. Compared with the non-MAFLD group, the annual increase in ba-PWV was highest in the persistent-MAFLD group [6.75 cm/s/year, (95% CI 4.03-9.33)], followed by the developed-[6.35 cm/s/year, (95% CI 3.80-8.91)] and the regressed-[1.27 cm/s/year, (95% CI - 2.18 to 4.72)] MAFLD groups. Similarly, compared with the non-MAFLD group, the persistent-MAFLD group had a 1.31-fold increased arterial stiffness risk [OR 1.31; 95% CI 1.03-1.66]. The associations of MAFLD transition patterns with arterial stiffness incidence did not differ across any clinically specific subgroups evaluated. Furthermore, the potential effect of dynamic changes in cardiometabolic risk factors on arterial stiffness incidence among persistent-MAFLD participants was mostly driven by annual fasting glucose and triglyceride increases. In conclusion, persistent MAFLD was associated with an increased risk of arterial stiffness development. Moreover, in persistent-MAFLD subjects, elevated blood glucose and triglyceride levels might facilitate the arterial stiffness incidence.

Metabolic dysfunction-associated fatty liver disease increased the risk of subclinical carotid atherosclerosis in China

Background and aims

Metabolic dysfunction-associated fatty liver disease (MAFLD) was proposed to substitute NAFLD in 2020. This new term highlights the systematic metabolic disturbances that accompany fatty liver. We evaluated the correlations between MAFLD and subclinical carotid atherosclerosis (SCA) based on a nationwide health examination population in China.

Methods

We performed a nationwide cross-sectional population and a Beijing retrospective cohort from 2009 to 2017. SCA was defined as elevated carotid intima-media thickness. The multivariable logistic and Cox models were used to analyze the association between MAFLD and SCA.

Results

153,482 participants were included in the cross-sectional study. MAFLD was significantly associated with SCA in fully adjusted models, with an odds ratio of 1.66; 95% confidence interval (CI): 1.62-1.70. This association was consistent in the cohort, with a hazard ratio (HR) of 1.31. The association between baseline MAFLD and incident SCA increased with hepatic steatosis severity. Subgroup analysis showed an interaction between age and MAFLD, with a higher risk in younger groups (HR:1.67, 95% CI: 1.17-2.40).

Conclusion

In this large cross-section and cohort study, MAFLD was significantly associated with the presence and development of SCA. Further, the risk was higher among MAFLD individuals with high hepatic steatosis index and young adults.

Aucubin administration suppresses STING signaling and mitigated high-fat diet-induced atherosclerosis and steatohepatosis in LDL receptor deficient mice

The rising obesity epidemic in developed countries is associated with many chronic inflammatory diseases including atherosclerosis and nonalcoholic steatohepatitis (NASH). Consuming aucubin may benefit health by suppressing inflammation. Herein, we studied the effects of aucubin consumption on atherosclerosis and NASH progression induced by high-fat diet (HFD) in LDL receptor deficient (LDLr^-/-) mice. Adult LDLr^-/- mice were fed with HFD for 12 weeks and received oral administration of aucubin for the last 6 weeks. Aucubin did not alter body weight or dyslipidemia, but lowered hyperglycemia and mitigated HFD-induced atherosclerosis and hepatic impairments in LDLr^-/- mice. Aucubin administration inhibited HFD-induced inflammation and downregulated mRNA and protein expression of stimulator of IFN genes (STING) in both aortas and livers of LDLr^-/- mice. In vitro, aucubin suppressed mitochondrial DNA (mtDNA)-induced activation of STING/NFκB pathway and downregulated gene expression of pro-inflammatory cytokines in cultured bone marrow-derived macrophages (BMDM). Furthermore, aucubin enhanced microRNA-181a-5p (miR-181a-5p) levels in both aortas and livers of LDLr^-/- mice. Importantly, miR-181a-5p mimicked the inhibitory effect of aucubin on STING/NFκB pathway and inflammation in BMDM. In conclusion, aucubin consumption attenuated HFD-induced atherosclerosis and NASH progression in LDLr^-/- mice, possibly through modulating miR-181a-5p/STING and inhibiting inflammation.

Hepatic transcript signatures predict atherosclerotic lesion burden prior to a 2-year high cholesterol, high fat diet challenge

The purpose of this study was to identify molecular mechanisms by which the liver influences total lesion burden in a nonhuman primate model (NHP) of cardiovascular disease with acute and chronic feeding of a high cholesterol, high fat (HCHF) diet. Baboons (47 females, 64 males) were fed a HCHF diet for 2 years (y); liver biopsies were collected at baseline, 7 weeks (w) and 2y, and lesions were quantified in aortic arch, descending aorta, and common iliac at 2y. Unbiased weighted gene co-expression network analysis (WGCNA) revealed several modules of hepatic genes correlated with lesions at different time points of dietary challenge. Pathway and network analyses were performed to study the roles of hepatic module genes. More significant pathways were observed in males than females. In males, we found modules enriched for genes in oxidative phosphorylation at baseline, opioid signaling at 7w, and EIF2 signaling and HNF1A and HNF4A networks at baseline and 2y. One module enriched for fatty acid β oxidation pathway genes was found in males and females at 2y. To our knowledge, this is the first study of a large NHP cohort to identify hepatic genes that correlate with lesion burden. Correlations of baseline and 7w module genes with lesions at 2y were observed in males but not in females. Pathway analyses of baseline and 7w module genes indicate EIF2 signaling, oxidative phosphorylation, and μ-opioid signaling are possible mechanisms that predict lesion formation induced by HCHF diet consumption in males. Our findings of coordinated hepatic transcriptional response in male baboons but not female baboons indicate underlying molecular mechanisms differ between female and male primate atherosclerosis.

Plaque progression at coronary CT angiography links non-alcoholic fatty liver disease and cardiovascular events: a prospective single-center study

OBJECTIVES

The presence of non-alcoholic fatty liver disease (NAFLD) has been associated with major adverse cardiovascular events (MACEs); however, the mechanisms that initiate the risk for MACEs in patients with NAFLD remain unknown. We sought to investigate whether plaque progression (PP), determined by coronary CT angiography (CCTA), moderate the relationship between NAFLD and MACEs.

METHODS

A total of 1683 asymptomatic participants (mean age, 63.3 ± 9.4 [range, 38-85] years; 1117 men) who underwent baseline and follow-up CCTA examination were prospectively included in our study. All of the participants were divided into the NAFLD and non-NAFLD groups. PP was determined by follow-up CCTA. The primary endpoint was MACEs, defined as the composite of all-cause death, nonfatal myocardial infarction, and unplanned hospitalization for acute coronary syndrome leading to revascularization.

RESULTS

At follow-up CCTA, participants with NAFLD showed higher incidence of PP than those without [33.0% (248/752) vs. 16.6% (155/931), p < 0.001]. Compared with non-NAFLD participants, participants with NAFLD had a lower 9.7-year event-free survival rate (80.9 vs. 66.4%, log-rank p < 0.001). Cox regression analysis revealed NAFLD was significantly associated with MACEs (HR = 1.63, 95% CI: 1.28 to 2.06, p < 0.001) after adjusting for covariables. However, this association was no longer significant after adjustment for PP (HR = 1.10, 95% CI: 0.84 to 1.45, p = 0.496). The mediation analysis revealed that PP had a significant indirect effect (β = 0.0587, 95% CI: 0.0424 to 0.08, p < 0.001) and mediated 99.8% (p = 0.002) for the relationship between NAFLD and MACEs.

CONCLUSIONS

Plaque progression, identified by follow-up CCTA, mediates the relationship between NAFLD and MACEs.

KEY POINTS

The incidence of CCTA-identified PP was higher for participants with NAFLD than those without NAFLD (248/752 [33.0%] vs. 155/931 [16.6%], p < 0.001). Participants with NAFLD had a lower 9.7-year event-free survival rate than those without NAFLD (66.4% vs. 80.9%, log-rank p < 0.001). The mediation analysis revealed that PP had a significant indirect effect (β = 0.0587, 95% CI: 0.0424 to 0.08, p < 0.001) and mediated 99.8% (p = 0.002) for the relationship between NAFLD and MACEs.

Nonalcoholic Steatohepatitis (NASH) and Atherosclerosis: Explaining Their Pathophysiology, Association and the Role of Incretin-Based Drugs

Nonalcoholic steatohepatitis (NASH) is the most severe manifestation of nonalcoholic fatty liver disease (NAFLD), a common complication of type 2 diabetes, and may lead to cirrhosis and hepatocellular carcinoma. Oxidative stress and liver cell damage are the major triggers of the severe hepatic inflammation that characterizes NASH, which is highly correlated with atherosclerosis and coronary artery disease. Regarding drug therapy, research on the role of GLP-1 analogues and DPP4 inhibitors, novel classes of antidiabetic drugs, is growing. In this review, we outline the association between NASH and atherosclerosis, the underlying molecular mechanisms, and the effects of incretin-based drugs, especially GLP-1 RAs, for the therapeutic management of these conditions.

Nonalcoholic fatty liver disease and health outcomes: An umbrella review of systematic reviews and meta-analyses

Purpose:

A large number of systemic reviews and meta-analyses have explored the relationship between nonalcoholic fatty liver disease (NAFLD) and multiple health outcomes. The aim of this study is to conduct an umbrella review to assess the strength and evidence for the association between NAFLD and health outcomes.

Methods:

We systematically identified the present meta-analyses of observational studies reporting an association between NAFLD and health outcomes. For each meta-analysis, we assessed the quality with AMSTAR2 and graded the epidemiologic evidence.

Results:

Fifty-four articles comprising 111 unique meta-analyses were included in this study. Eighty-five unique outcomes showed significant associations ( P ← 0.05), whereas 26 unique outcomes showed insignificant associations, and we cannot assess the epidemiologic evidence. For 85 significant health outcomes, four outcomes (carotid intima-media thickness (C-IMT), peak A velocity, left ventricle end-diastolic diameter, incident chronic kidney disease (CKD) in adult patients) was graded as high quality of evidence, 23 outcomes were graded as the moderate quality of evidence, and the remaining 58 outcomes were graded as weak quality of evidence. Fourty-seven (87.03%) studies showed critically low methodological quality.

Conclusion:

In this umbrella review, only four statistically significant health outcomes showed high epidemiologic evidence. NAFLD seems to relate to an increased risk of C-IMT, peak A velocity, left ventricle end-diastolic diameter, and incident CKD in adult patients.

Emerging Role of Nuclear Receptors for the Treatment of NAFLD and NASH

Non-alcoholic fatty liver (NAFLD) over the past years has become a metabolic pandemic linked to a collection of metabolic diseases. The nuclear receptors ERRs, REV-ERBs, RORs, FXR, PPARs, and LXR are master regulators of metabolism and liver physiology. The characterization of these nuclear receptors and their biology has promoted the development of synthetic ligands. The possibility of targeting these receptors to treat NAFLD is promising, as several compounds including Cilofexor, thiazolidinediones, and Saroglitazar are currently undergoing clinical trials. This review focuses on the latest development of the pharmacology of these metabolic nuclear receptors and how they may be utilized to treat NAFLD and subsequent comorbidities.

Coronary CT Angiography in Asymptomatic Adults with Hepatic Steatosis

Background The long-term prognostic value of coronary CT angiography (CCTA) in asymptomatic adults with hepatic steatosis (HS) remains unknown. Purpose To evaluate the long-term prognostic value of CCTA in asymptomatic adults with HS. Materials and Methods Between January 2009 and December 2013, consecutive asymptomatic adults who underwent CCTA evaluation and unenhanced abdominal CT were prospectively enrolled. All participants were divided into two groups-with HS and without HS according to abdominal CT results. The primary end point was major adverse cardiovascular events (MACEs), defined as cardiac death, stroke, myocardial infarction, and angina requiring hospitalization. Multivariable Cox regression analysis and Kaplan-Meier analysis were used to compare survival rates. Results One thousand thirteen participants with HS and 1940 participants without HS who completed the follow-up were included (mean age, 66 years ± 10 [standard deviation] [range, 29-90 years]; 1940 men). During a median of 7.2 years of follow-up (interquartile range, 6.3-8.1), MACEs were observed in 96 of 1013 participants with HS (10%), whereas 80 of 1940 participants without HS (4%) had MACEs. In participants with a Coronary Artery Disease Reporting and Data System (CAD-RADS) category of 0, both participants with and without HS had a similar 8.8-year event-free survival rate (99.2% event-free survival rate in participants with HS vs 99.0% event-free survival rate in participants without HS, P = .77). As for participants with CAD-RADS categories 1 or 2 or 3-5, the 8.8-year event-free survival rate was lower in participants with HS than in those without HS (70.6% vs 85.2%, P < .001; 51.4% vs 71.7%, P = .03, respectively). The risk of MACEs was higher for participants with HS than for those without HS in CAD-RADS categories 1 and 2 (adjusted hazard ratio = 2.3; 95% CI: 1.4, 3.9; P < .001) and CAD-RADS categories 3-5 (adjusted HR = 2.1; 95% CI: 1.2, 3.6; P = .006) but not in the setting of CAD-RADS category 0 (adjusted HR = 5.1; 95% CI: 0.1, 398; P = .47). Conclusion Asymptomatic participants with hepatic steatosis (HS) had a worse prognosis than those without HS in the presence of coronary artery disease (CAD) at coronary CT angiography, whereas participants with HS and without CAD might have excellent clinical outcomes during a median follow-up of 7.2 years. © RSNA, 2021 Online supplemental material is available for this article.

Cysteamine Decreases Low-Density Lipoprotein Oxidation, Causes Regression of Atherosclerosis, and Improves Liver and Muscle Function in Low-Density Lipoprotein Receptor-Deficient Mice

Background

We have shown previously that low‐density lipoprotein (LDL) can be oxidized in the lysosomes of macrophages, that this oxidation can be inhibited by cysteamine, an antioxidant that accumulates in lysosomes, and that this drug decreases atherosclerosis in LDL receptor–deficient mice fed a high‐fat diet. We have now performed a regression study with cysteamine, which is of more relevance to the treatment of human disease.

Methods and Results

LDL receptor–deficient mice were fed a high‐fat diet to induce atherosclerotic lesions. They were then reared on chow diet and drinking water containing cysteamine or plain drinking water. Aortic atherosclerosis was assessed, and samples of liver and skeletal muscle were analyzed. There was no regression of atherosclerosis in the control mice, but cysteamine caused regression of between 32% and 56% compared with the control group, depending on the site of the lesions. Cysteamine substantially increased markers of lesion stability, decreased ceroid, and greatly decreased oxidized phospholipids in the lesions. The liver lipid levels and expression of cluster of differentiation 68, acetyl–coenzyme A acetyltransferase 2, cytochromes P450 (CYP)27, and proinflammatory cytokines and chemokines were decreased by cysteamine. Skeletal muscle function and oxidative fibers were increased by cysteamine. There were no changes in the plasma total cholesterol, LDL cholesterol, high‐density lipoprotein cholesterol, or triacylglycerol concentrations attributable to cysteamine.

Conclusions

Inhibiting the lysosomal oxidation of LDL in atherosclerotic lesions by antioxidants targeted at lysosomes causes the regression of atherosclerosis and improves liver and muscle characteristics in mice and might be a promising novel therapy for atherosclerosis in patients.

Metabolic drivers of non-alcoholic fatty liver disease

BACKGROUND

The incidence of non-alcoholic fatty liver disease (NAFLD) is rapidly increasing worldwide parallel to the global obesity epidemic. NAFLD encompasses a range of liver pathologies and most often originates from metabolically driven accumulation of fat in the liver, or non-alcoholic fatty liver (NAFL). In a subset of NAFL patients, the disease can progress to non-alcoholic steatohepatitis (NASH), which is a more severe form of liver disease characterized by hepatocyte injury, inflammation, and fibrosis. Significant progress has been made over the past decade in our understanding of NASH pathogenesis, but gaps remain in our mechanistic knowledge of the precise metabolic triggers for disease worsening.

SCOPE OF REVIEW

The transition from NAFL to NASH likely involves a complex constellation of multiple factors intrinsic and extrinsic to the liver. This review focuses on early metabolic events in the establishment of NAFL and initial stages of NASH. We discuss the association of NAFL with obesity as well as the role of adipose tissue in disease progression and highlight early metabolic drivers implicated in the pathological transition from hepatic fat accumulation to steatohepatitis.

MAJOR CONCLUSIONS

The close association of NAFL with features of metabolic syndrome highlight plausible mechanistic roles for adipose tissue health and the release of lipotoxic lipids, hepatic de novo lipogenesis (DNL), and disruption of the intestinal barrier in not only the initial establishment of hepatic steatosis, but also in mediating disease progression. Human genetic variants linked to NASH risk to date are heavily biased toward genes involved in the regulation of lipid metabolism, providing compelling support for the hypothesis that NASH is fundamentally a metabolic disease.

HSP25 Vaccination Attenuates Atherogenesis via Upregulation of LDLR Expression, Lowering of PCSK9 Levels and Curbing of Inflammation

[Figure: see text].

Innate Immune Cells in the Adipose Tissue in Health and Metabolic Disease

Metabolic disorders, such as obesity, type 2 diabetes mellitus, and nonalcoholic fatty liver disease, are characterized by chronic low-grade tissue and systemic inflammation. During obesity, the adipose tissue undergoes immunometabolic and functional transformation. Adipose tissue inflammation is driven by innate and adaptive immune cells and instigates insulin resistance. Here, we discuss the role of innate immune cells, that is, macrophages, neutrophils, eosinophils, natural killer cells, innate lymphoid type 2 cells, dendritic cells, and mast cells, in the adipose tissue in the healthy (lean) and diseased (obese) state and describe how their function is shaped by the obesogenic microenvironment, and humoral, paracrine, and cellular interactions. Moreover, we particularly outline the role of hypoxia as a central regulator in adipose tissue inflammation. Finally, we discuss the long-lasting effects of adipose tissue inflammation and its potential reversibility through drugs, caloric restriction, or exercise training.

Non-alcoholic fatty liver disease and the incidence of myocardial infarction: A cohort study

BACKGROUND AND AIM

Non-alcoholic fatty liver disease (NAFLD) is a multisystem disease associated with an increased risk of cardiovascular disease (CVD), diabetes, and chronic kidney disease. Indeed, CVD is the most common cause of death in NAFLD patients. This study aimed to evaluate the association between NAFLD and the risk of incident myocardial infarction.

METHODS

This is a retrospective cohort study involving 111 492 adults over 40 years old without history of CVD, liver disease, or cancer at baseline who participated in a regular health screening exam between 2003 and 2013. Fatty liver was diagnosed by ultrasonography.

RESULTS

During 725 706.9 person-years of follow-up, 183 participants developed myocardial infarction (incidence rate 0.3 cases per 1000 person-years). The age, sex, and year of visit-adjusted hazard ratio (HR) for incident myocardial infarction comparing participants with NAFLD with those without it was 2.14 (95% confidence interval 1.59, 2.89). This association remained significant in fully adjusted models (HR 1.54; 95% confidence interval 1.11, 2.14). Compared with participants without NAFLD, in participants with low NAFLD fibrosis score (NFS) (< -1.455) and with intermediate-to-high NFS (≥ -1.455), the fully adjusted HRs for incident myocardial infarction were 1.70 (1.22, 2.36) and 1.88 (1.24, 2.87), respectively.

CONCLUSION

In this large cohort study, NAFLD was associated with an increased incidence of myocardial infarction independently of established risk factors. In addition, this association was similar in participants with and without evidence of more advanced NAFLD as indicated by the NFS. NAFLD patients may need to be carefully monitored and managed early to prevent myocardial infarction.

Targeting the Inositol Pyrophosphate Biosynthetic Enzymes in Metabolic Diseases

In mammals, a family of three inositol hexakisphosphate kinases (IP6Ks) synthesizes the inositol pyrophosphate 5-IP7 from IP6. Genetic deletion of Ip6k1 protects mice from high fat diet induced obesity, insulin resistance and fatty liver. IP6K1 generated 5-IP7 promotes insulin secretion from pancreatic β-cells, whereas it reduces insulin signaling in metabolic tissues by inhibiting the protein kinase Akt. Thus, IP6K1 promotes high fat diet induced hyperinsulinemia and insulin resistance in mice while its deletion has the opposite effects. IP6K1 also promotes fat accumulation in the adipose tissue by inhibiting the protein kinase AMPK mediated energy expenditure. Genetic deletion of Ip6k3 protects mice from age induced fat accumulation and insulin resistance. Accordingly, the pan IP6K inhibitor TNP [N2-(m-trifluorobenzyl), N6-(p-nitrobenzyl)purine] ameliorates obesity, insulin resistance and fatty liver in diet induced obese mice by improving Akt and AMPK mediated insulin sensitivity and energy expenditure. TNP also protects mice from bone loss, myocardial infarction and ischemia reperfusion injury. Thus, the IP6K pathway is a potential target in obesity and other metabolic diseases. Here, we summarize the studies that established IP6Ks as a potential target in metabolic diseases. Further studies will reveal whether inhibition of this pathway has similar pleiotropic benefits on metabolic health of humans.

Amitriptyline inhibits nonalcoholic steatohepatitis and atherosclerosis induced by high-fat diet and LPS through modulation of sphingolipid metabolism

We reported previously that increased acid sphingomyelinase (ASMase)-catalyzed hydrolysis of sphingomyelin, which leads to increases in ceramide and sphingosine 1 phosphate (S1P), played a key role in the synergistic upregulation of proinflammatory cytokines by palmitic acid (PA), a major saturated fatty acid, and lipopolysaccharide (LPS) in macrophages. Since macrophages are vital players in nonalcoholic steatohepatitis (NASH) and atherosclerosis, we assessed the effect of ASMase inhibition on NASH and atherosclerosis cooperatively induced by high-PA-containing high-fat diet (HP-HFD) and LPS in LDL receptor-deficient (LDLR-/-) mice. LDLR-/- mice were fed HP-HFD, injected with low dose of LPS and treated with or without the ASMase inhibitor amitriptyline. The neutral sphingomyelinase inhibitor GW4869 was used as control. Metabolic study showed that both amitriptyline and GW4869 reduced glucose, lipids, and insulin resistance. Histological analysis and Oil Red O staining showed that amitriptyline robustly reduced hepatic steatosis while GW4869 had modest effects. Interestingly, immunohistochemical study showed that amitriptyline, but not GW4869, strongly reduced hepatic inflammation. Furthermore, results showed that both amitriptyline and GW4869 attenuated atherosclerosis. To elucidate the underlying mechanisms whereby amitriptyline inhibited both NASH and atherosclerosis, but GW4869 only inhibited atherosclerosis, we found that amitriptyline, but not GW4869, downregulated proinflammatory cytokines in macrophages. Finally, we found that inhibition of sphingosine 1 phosphate production is a potential mechanism whereby amitriptyline inhibited proinflammatory cytokines. Collectively, this study showed that amitriptyline inhibited NASH and atherosclerosis through modulation of sphingolipid metabolism in LDLR-/- mice, indicating that sphingolipid metabolism in macrophages plays a crucial role in the linkage of NASH and atherosclerosis.

Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is considered the hepatic manifestation of the metabolic syndrome (MetS) and comprises one of the largest health threats of the twenty-first century. In this chapter, we review the current state of knowledge of NAFLD and underline the striking similarities with atherosclerosis. We first describe current epidemiological data showing the staggering increase of NAFLD numbers and its related clinical and economic costs. We then provide an overview of pathophysiological hepatic processes in NAFLD and highlight the systemic aspects of NAFLD that point toward metabolic crosstalk between organs as an important cause of metabolic disease. Finally, we end by highlighting the currently investigated therapeutic approaches for NAFLD, which also show strong similarities with a range of treatment options for atherosclerosis.

Inflammation and Ectopic Fat Deposition in the Aging Murine Liver Is Influenced by CCR2

Aging is associated with inflammation and metabolic syndrome, which manifests in the liver as nonalcoholic fatty liver disease (NAFLD). NAFLD can range in severity from steatosis to fibrotic steatohepatitis and is a major cause of hepatic morbidity. However, the pathogenesis of NAFLD in naturally aged animals is unclear. Herein, we performed a comprehensive study of lipid content and inflammatory signature of livers in 19-month-old aged female mice. These animals exhibited increased body and liver weight, hepatic triglycerides, and inflammatory gene expression compared with 3-month-old young controls. The aged mice also had a significant increase in F4/80⁺ hepatic macrophages, which coexpressed CD11b, suggesting a circulating monocyte origin. A global knockout of the receptor for monocyte chemoattractant protein (CCR2) prevented excess steatosis and inflammation in aging livers but did not reduce the number of CD11b⁺ macrophages, suggesting changes in macrophage accumulation precede or are independent from chemokine (C-C motif) ligand-CCR2 signaling in the development of age-related NAFLD. RNA sequencing further elucidated complex changes in inflammatory and metabolic gene expression in the aging liver. In conclusion, we report a previously unknown accumulation of CD11b⁺ macrophages in aged livers with robust inflammatory and metabolic transcriptomic changes. A better understanding of the hallmarks of aging in the liver will be crucial in the development of preventive measures and treatments for end-stage liver disease in elderly patients.

Cell-specific elevation of Runx2 promotes hepatic infiltration of macrophages by upregulating MCP-1 in high-fat diet-induced mice NAFLD

OBJECTIVE

We have demonstrated runt-related transcription factor 2 (Runx2) plays important role in atherosclerosis. It has been indicated that atherosclerosis shares the similar histopathology with nonalcoholic steatohepatitis (NASH), a progressive stage of nonalcoholic fatty liver disease (NAFLD), on macrophages infiltration. However, the function of Runx2 in NAFLD is completely unknown. Here, we investigated the underlying mechanism of Runx2 triggering macrophages infiltration in the development of NAFLD.

METHODS

Mice were fed with high-fat diet (HFD) for a long time. Histopathologic features, macrophages infiltration, expression of monocyte chemotactic protein 1 (MCP-1), and Runx2 were, respectively, analyzed in vivo. Lentivirus or short interfering RNA were transfected in murine hepatic stellate cells (HSCs) and the transwell assay was performed to verify the contribution of Runx2 for macrophages migration in vitro.

RESULTS

Long-term treatment with HFD induced the progression of NAFLD, and NASH was initiated from 8 months on diet. HFD increased the expression of F4/80 upon HFD feeding, indicated HFD promotes hepatic infiltration of macrophages in NAFLD. In addition, HFD upregulated the expression of MCP-1 and Runx2 during NAFLD development. Unexpectedly, Runx2 upregulation is cell-type depended in NAFLD, and only abundantly elevated in activated HSCs. Furthermore, we found that Runx2 could increase or decrease the expression of MCP-1 in HSCs, and regulate macrophages migration by influencing MCP-1 production in vitro.

CONCLUSIONS

Our results give evidence that the upregulation of Runx2 specific in activated HSCs promotes hepatic infiltration of macrophages by increasing MCP-1 expression in NAFLD, which reveals a novel mechanism and provides a cell-specific therapeutic target for NAFLD.

Randomized controlled trials - mechanistic studies of testosterone and the cardiovascular system

Testosterone deficiency is common in men with cardiovascular disease (CVD), and randomized placebo-controlled trials (RCTs) have reported beneficial effects of testosterone therapy on exercise-induced cardiac ischemia in chronic stable angina, functional exercise capacity, maximum oxygen consumption during exercise (VO_2max) and muscle strength in chronic heart failure (CHF), shortening of the Q-T interval, and improvement of some cardiovascular risk factors. Testosterone deficiency is associated with an adverse CV risk profile and mortality. Clinical and scientific studies have provided mechanistic evidence to support and explain the findings of the RCTs. Testosterone is a rapid-onset arterial vasodilator within the coronary circulation and other vascular beds including the pulmonary vasculature and can reduce the overall peripheral systemic vascular resistance. Evidence has demonstrated that testosterone mediates this effect on vascular reactivity through calcium channel blockade (L-calcium channel) and stimulates potassium channel opening by direct nongenomic mechanisms. Testosterone also stimulates repolarization of cardiac myocytes by stimulating the ultra-rapid potassium channel-operated current. Testosterone improves cardiac output, functional exercise capacity, VO_2max and vagally mediated arterial baroreceptor cardiac reflex sensitivity in CHF, and other mechanisms. Independent of the benefit of testosterone on cardiac function, testosterone substitution may also increase skeletal muscle glucose metabolism and enhance muscular strength, both factors that could contribute to the improvement in functional exercise capacity may include improved glucose metabolism and muscle strength. Testosterone improves metabolic CV risk factors including body composition, insulin resistance, and hypercholesterolemia by improving both glucose utilization and lipid metabolism by a combination of genomic and nongenomic actions of glucose uptake and utilization expression of the insulin receptor, glucose transporters, and expression on regulatory enzymes of key metabolic pathways. The effect on high-density lipoprotein-cholesterol (HDL-C) differs between studies in that it has been found to fall, rise, or have no change in levels. Testosterone replacement can suppress the levels of circulating pro-inflammatory cytokines and stimulate the production of interleukin-10 (IL-10) which has anti-inflammatory and anti-atherogenic actions in men with CVD. No effect on C-reactive protein has been detected. No adverse effects on clotting factors have been detected. RCTs have not clearly demonstrated any significant evidence that testosterone improves or adversely affects the surrogate markers of atherosclerosis such as reduction in carotid intima thickness or coronary calcium deposition. Any effect of testosterone on prevention or amelioration of atherosclerosis is likely to occur over years as shown in statin therapy trials and not months as used in testosterone RCTs. The weight of evidence from long-term epidemiological studies supports a protective effect as evidenced by a reduction in major adverse CV events (MACEs) and mortality in studies which have treated men with testosterone deficiency. No RCT where testosterone has been replaced to the normal healthy range has reported a significant benefit or adverse effect on MACE nor has any recent meta-analysis.

Deletion of hematopoietic Dectin-2 or CARD9 does not protect against atherosclerotic plaque formation in hyperlipidemic mice

Inflammatory reactions activated by pattern recognition receptors (PRRs) on the membrane of innate immune cells play an important role in atherosclerosis. Whether the PRRs of the C-type lectin receptor (CLR) family including Dectin-2 may be involved in the pathogenesis of atherosclerosis remains largely unknown. Recently, the CLR-adaptor molecule caspase recruitment domain family member 9 (CARD9) has been suggested to play a role in cardiovascular pathologies as it provides the link between CLR activation and transcription of inflammatory cytokines as well as immune cell recruitment. We therefore evaluated whether hematopoietic deletion of Dectin-2 or CARD9 reduces inflammation and atherosclerosis development. Low-density lipoprotein receptor (Ldlr)-knockout mice were transplanted with bone marrow from wild-type, Dectin-2- or Card9-knockout mice and fed a Western-type diet containing 0.1% (w/w) cholesterol. After 10 weeks, lipid and inflammatory parameters were measured and atherosclerosis development was determined. Deletion of hematopoietic Dectin-2 or CARD9 did not influence plasma triglyceride and cholesterol levels. Deletion of hematopoietic Dectin-2 did not affect atherosclerotic lesion area, immune cell composition, ex vivo cytokine secretion by peritoneal cells or bone marrow derived macrophages. Unexpectedly, deletion of hematopoietic CARD9 increased atherosclerotic lesion formation and lesion severity. Deletion of hematopoietic CARD9 did also not influence circulating immune cell composition and peripheral cytokine secretion. Besides a tendency to a reduced macrophage content within these lesions, plasma MCP-1 levels decreased upon WTD feeding. Deletion of hematopoietic Dectin-2 did not influence atherosclerosis development in hyperlipidemic mice. The absence of CARD9 unexpectedly increased atherosclerotic lesion size and severity, suggesting that the presence of CARD9 may protect against initiation of atherosclerosis development.

Innate immune cells in the adipose tissue

Immune cells are present in the adipose tissue (AT) and regulate its function. Under lean conditions, immune cells predominantly of type 2 immunity, including eosinophils, M2-like anti-inflammatory macrophages and innate lymphoid cells 2, contribute to the maintenance of metabolic homeostasis within the AT. In the course of obesity, pro-inflammatory immune cells, such as M1-like macrophages, prevail in the AT. Inflammation in the obese AT is associated with the development of metabolic complications such as insulin resistance, type 2 diabetes and cardiovascular disease. Thus, the immune cell-adipocyte crosstalk in the AT is an important regulator of AT function and systemic metabolism. We discuss herein this crosstalk with a special focus on the role of innate immune cells in AT inflammation and metabolic homeostasis in obesity.

Ultrasonic Perfluorohexane-Loaded Monocyte Imaging: Toward a Minimally Invasive Technique for Selective Detection of Liver Inflammation in Fatty Liver Disease

OBJECTIVES

To investigate the utility of ultrasonic (US) perfluorohexane (PFH)-loaded monocyte imaging for detection of liver inflammation in fatty liver disease.

METHODS

C57Bl6 mice were injected intraperitoneally with tumor necrosis factor α and assessed by US PFH-loaded monocyte imaging 3 hours later. Echogenic monocytes were injected intravenously, leading to a transient increase in liver tissue intensity on a US perfusion scan. The contrast wash-out time constant was hypothesized to reflect the degree of inflammation. Next, we evaluated US PFH-loaded monocyte imaging in Ldlr^-/- mice fed a 1-week high-fat/high-cholesterol diet as model for early developing nonalcoholic steatohepatitis. Adjunct analyses included tissue markers of liver inflammation.

RESULTS

Tumor necrosis factor α-injected mice showed a reduced wash-out time constant (mean ± SEM, 0.013 ± 0.003; n = 8) compared to controls (0.054 ± 0.009; n = 7; P = .0006), indicative of increased inflammatory adhesion molecule expression on the endothelium. The Ldlr^-/- mice fed the high-fat/high-cholesterol diet showed liver inflammation, as reflected by increased (3- to 4-fold) infiltration of inflammatory cells and increased (3- to 4-fold) gene expression of tumor necrosis factor α, integrin αM, intracellular adhesion molecule, and vascular cell adhesion molecule. However, in these mice, no difference was detected in the wash-out time constant as assessed by US PFH-loaded monocyte imaging (high-fat/high-cholesterol, 0.050 ± 0.017; n = 5; chow, 0.048 ± 0.006; n = 6; P = .91).

CONCLUSIONS

Our results indicate that US PFH-loaded monocyte imaging is able to detect vascularly expressed inflammatory adhesion molecules in the mouse liver on direct endothelial stimulation. However, in our mouse model of early developing nonalcoholic steatohepatitis, we did not detect inflammation by this method, which may suggest that the time-dependent relationship between parenchymal and endothelial inflammation remains a fundamental issue to be addressed.

Nonalcoholic fatty liver disease contributes to subclinical atherosclerosis: A systematic review and meta-analysis

Nonalcoholic fatty liver disease (NAFLD) is associated with an increased risk of atherosclerotic cardiovascular disease. In our meta‐analysis, we aimed to assess the correlation of NAFLD and four surrogate markers of subclinical atherosclerosis. PubMed, Embase, and the Cochrane Library were searched up until April 2017. Original studies investigating the association between NAFLD and subclinical atherosclerosis were included. The outcome data were extracted and pooled for the effect estimate by using a random‐effects model. We used the Newcastle‐Ottawa Quality Assessment Scale to assess the quality of the included studies. Of the 434 initially retrieved studies, 26 studies involving a total of 85,395 participants (including 29,493 patients with NAFLD) were included in this meta‐analysis. The Newcastle‐Ottawa Quality Assessment Scale scores suggested the included studies were of high quality. The pooled effects estimate showed that subjects with NAFLD exhibited a significant independent association with subclinical atherosclerosis compared to the non‐NAFLD group (odds ratio, 1.60; 95% confidence interval, 1.45‐1.78). Subgroup analysis suggested that the presence of NAFLD yielded a remarkable higher risk of increased carotid artery intima‐media thickness/plaques, arterial stiffness, coronary artery calcification, and endothelial dysfunction with odds ratios (95% confidence interval) of 1.74 (1.47‐2.06), 1.56 (1.24‐1.96), 1.40 (1.22‐1.60), and 3.73 (0.99‐14.09), respectively. Conclusion: Our meta‐analysis revealed a close link between NAFLD and subclinical atherosclerosis in light of four different indices. Patients with NAFLD might benefit from screening and surveillance of early atherosclerosis, which would facilitate the prediction of potential cardiovascular disease burden, risk stratification, and appropriate intervention in the long term. (Hepatology Communications 2018;2:376‐392)

IL-33 treatment attenuated diet-induced hepatic steatosis but aggravated hepatic fibrosis

The aim of our work was to investigate the role of interleukin-33 (IL-33) and its receptor ST2 in the progression of diet-induced nonalcoholic steatohepatitis (NASH) in mice, and the characteristic expression in livers of patients with NASH. Mice were fed with high-fat diet (HFD) or methionine-choline 4-deficient diet (MCD) and injected intraperitoneally with IL-33. Both mRNA and protein expression levels of IL-33 and ST2 were up-regulated in the livers of mice fed with HFD or MCD. Treatment with IL-33 attenuated diet-induced hepatic steatosis and reduced activities of ALT in serum, as well as ameliorated HFD-induced systemic insulin resistance and glucose intolerance, while aggravated hepatic fibrosis in diet-induced NASH. Furthermore, treatment with IL-33 can also promote Th2 response and M2 macrophage activation and beneficial modulation on expression profiles of fatty acid metabolism genes in livers. ST2 deficiency did not affect hepatic steatosis and fibrosis when fed with controlling diet. IL-33 did not affect diet-induced hepatic steatosis and fibrosis in ST2 knockout mice. Meanwhile, in the livers of patients with NASH, IL-33 was mainly located in hepatic sinusoid, endothelial cells, and hepatic stellate cells. The mRNA expression level of IL-33 and ST2 was elevated with the progression of NASH. In conclusion, treatment with IL-33 attenuated diet-induced hepatic steatosis, but aggravated hepatic fibrosis, in a ST2-dependent manner.

Gliptins Suppress Inflammatory Macrophage Activation to Mitigate Inflammation, Fibrosis, Oxidative Stress, and Vascular Dysfunction in Models of Nonalcoholic Steatohepatitis and Liver Fibrosis

AIMS

Nonalcoholic steatohepatitis (NASH) is characterized by steatosis, panlobular inflammation, liver fibrosis, and increased cardiovascular mortality. Dipeptidyl peptidase-4 inhibitors (gliptins) are indirect glucagon-like peptide 1 agonists with antidiabetic and anti-inflammatory activity, used for the treatment of type 2 diabetes. Their potential and underlying mechanisms to treat metabolic liver inflammation and fibrosis as well as the associated vascular dysfunction remain to be explored.

RESULTS

In the methionine/choline-deficient (MCD) diet and Mdr2^-/- models of NASH and liver fibrosis, treatment with sitagliptin and linagliptin significantly decreased parameters of steatosis and inflammation, which was accompanied by suppression of hepatic transcript levels reflecting metabolic inflammation and fibrosis, including SREBP-1c, FAS, TNFα, iNOS, α-SMA, Col1α1, and MMP-12. Moreover, gliptins reduced the number of liver infiltrating CD11b⁺Ly6C^hi proinflammatory monocytes/macrophages and liver-resident F4/80⁺ macrophages, with an increase of Ym1⁺ alternative macrophages and (anti-inflammatory) macrophage markers Arg1 and IL-10. This was paralleled by decreased hepatic and aortic reactive oxygen species (ROS) production and NOX-2 mRNA expression, a normalization of endothelial dysfunction, cardiac NADPH oxidase activity, mitochondrial ROS formation, and whole blood oxidative burst in the MCD model. Innovation and Conclusions: Gliptins via suppression of inflammation decrease steatosis, apoptosis, oxidative stress, and vascular dysfunction in murine models of NASH and liver fibrosis, with mild direct antifibrotic properties. They reduce the numbers of liver and vascular inflammatory monocytes/macrophages and induce their alternative polarization, with beneficial effect on NASH-associated hepatic and cardiovascular complications. Therefore, gliptins qualify as drugs for treatment of NASH and associated liver fibrosis and cardiovascular complications. Antioxid. Redox Signal. 28, 87-109.

Neutrophil depletion improves diet-induced non-alcoholic fatty liver disease in mice

PURPOSE

Non-alcoholic fatty liver disease is highly associated with morbidity and mortality in population. Although studies have already demonstrated that the immune response plays a pivotal role in the development of non-alcoholic fatty liver disease, the comprehensive regulation is unclear. Therefore, present study was carried out to investigate the non-alcoholic fatty liver disease development under neutrophil depletion.

METHODS

To achieve the aim of the study, C57BL/6 J mice were fed with high fat diet for 6 weeks before treated with neutrophil deplete antibody 1A8 or isotype control (200 μg/ mouse every week) for another 4 weeks.

RESULTS

Treated with 1A8 antibody, obese mice exhibited better whole body metabolic parameters, including reduction of body weight gain and fasting blood glucose levels. Neutrophil depletion also effectively reduced hepatic structural disorders, dysfunction and lipid accumulation. Lipid β-oxidative markers, phosphorylated-AMP-activated protein kinase α and phosphorylated-acetyl-CoA carboxylase levels were increased in 1A8 antibody-treated obese mouse group. The mitochondrial number and function were also reversed after 1A8 antibody treatment, including increased mitochondrial number, reduced lipid oxidative damage and enhanced mitochondrial activity. Furthermore, the expression of inflammatory cytokines, tumor necrosis factor-α, interleukin-6, and monocyte chemoattractant protein-1 were obviously reduced after neutrophil depletion, accompanied with decreased F4/80 mRNA level and macrophage percentage in liver. The decreased NF-κB signaling activity was also involved in the beneficial effect of neutrophil depletion.

CONCLUSION

Taken together, neutrophil depletion could attenuate metabolic syndromes and hepatic dysfunction.

The effect of fibroblast growth factor 15 deficiency on the development of high fat diet induced non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH) is a form of non-alcoholic fatty liver disease (NAFLD) characterized by steatosis, inflammation, and fibrosis often associated with metabolic syndrome. Fibroblast growth factor 15 (FGF15), an endocrine factor mainly produced in the distal part of small intestine, has emerged to be a critical factor in regulating bile acid homeostasis, energy metabolism, and liver regeneration. We hypothesized that FGF15 alters the development of each of the listed features of NASH. To test this hypothesis, four-week old male Fgf15^-/- and their corresponding wild-type (WT) mice were fed either a high fat diet (HFD) or a control chow diet for six months. The results confirmed that HFD feeding for six months in WT mice recapitulated human NASH phenotype, including macrovesicular steatosis, inflammation, and fibrosis. Whereas FGF15 deficiency had no effect on the severity of liver steatosis or inflammation, it was associated with decreased liver fibrosis. Furthermore, FGF15 deficiency resulted in abnormal bile acid homeostasis, increased insulin resistance, increased HFD-induced serum triglycerides, decreased inductions of hepatic cholesterol content by HFD, and altered gene expression of lipid metabolic enzymes. These data suggest that FGF15 improves lipid homeostasis and reduces bile acid synthesis, but promotes fibrosis during the development of NASH.

The Combination of Blueberry Juice and Probiotics Ameliorate Non-Alcoholic Steatohepatitis (NASH) by Affecting SREBP-1c/PNPLA-3 Pathway via PPAR-α

Nonalcoholic steatohepatitis (NASH) is liver inflammation and a major threat to public health. Several pharmaceutical agents have been used for NASH therapy but their high-rate side effects limit the use. Blueberry juice and probiotics (BP) have anti-inflammation and antibacterial properties, and may be potential candidates for NASH therapy. To understand the molecular mechanism, Sprague Dawley rats were used to create NASH models and received different treatments. Liver tissues were examined using HE (hematoxylin and eosin) and ORO (Oil Red O) stain, and serum biochemical indices were measured. The levels of peroxisome proliferators-activated receptor (PPAR)-α, sterol regulatory element binding protein-1c (SREBP-1c), Patatin-like phospholipase domain-containing protein 3 (PNPLA-3), inflammatory cytokines and apoptosis biomarkers in liver tissues were measured by qRT-PCR and Western blot. HE and ORO analysis indicated that the hepatocytes were seriously damaged with more and larger lipid droplets in NASH models while BP reduced the number and size of lipid droplets (p < 0.05). Meanwhile, BP increased the levels of SOD (superoxide dismutase), GSH (reduced glutathione) and HDL-C (high-density lipoprotein cholesterol), and reduced the levels of AST (aspartate aminotransferase), ALT (alanine aminotransferase), TG (triglycerides), LDL-C (low-density lipoprotein cholesterol) and MDA (malondialdehyde) in NASH models (p < 0.05). BP increased the level of PPAR-α (Peroxisome proliferator-activated receptor α), and reduced the levels of SREBP-1c (sterol regulatory element binding protein-1c) and PNPLA-3 (Patatin-like phospholipase domain-containing protein 3) (p < 0.05). BP reduced hepatic inflammation and apoptosis by affecting IL-6 (interleukin 6), TNF-α (Tumor necrosis factor α), caspase-3 and Bcl-2 in NASH models. Furthermore, PPAR-α inhibitor increased the level of SREBP-1c and PNPLA-3. Therefore, BP prevents NASH progression by affecting SREBP-1c/PNPLA-3 pathway via PPAR-α.

Non-alcoholic fatty liver disease and progression of coronary artery calcium score: a retrospective cohort study

BACKGROUND AND AIM

Non-alcoholic fatty liver disease (NAFLD), a hepatic manifestation of the metabolic syndrome, was associated with subclinical atherosclerosis in many cross-sectional studies, but the prospective association between NAFLD and the progression of atherosclerosis has not been evaluated. This study was conducted to evaluate the association between NAFLD and the progression of coronary atherosclerosis.

METHODS

This retrospective cohort study included 4731 adult men and women with no history of cardiovascular disease (CVD), liver disease or cancer at baseline who participated in a repeated regular health screening examination between 2004 and 2013. Fatty liver was diagnosed by ultrasound based on standard criteria, including parenchymal brightness, liver-to-kidney contrast, deep beam attenuation and bright vessel walls. Progression of coronary artery calcium (CAC) scores was measured using multidetector CT scanners.

RESULTS

The average duration of follow-up was 3.9 years. During follow-up, the annual rate of CAC progression in participants with and without NAFLD were 22% (95% CI 20% to 23%) and 17% (16% to 18%), respectively (p<0.001). The multivariable ratio of progression rates comparing participants with NAFLD with those without NAFLD was 1.04 (1.02 to 1.05; p<0.001). The association between NAFLD and CAC progression was similar in most subgroups analysed, including in participants with CAC 0 and in those with CAC >0 at baseline.

CONCLUSIONS

In this large cohort study of adult men and women with no history of CVD, NAFLD was significantly associated with the development of CAC independent of cardiovascular and metabolic risk factors. NAFLD may play a pathophysiological role in atherosclerosis development and may be useful to identify subjects with a higher risk of subclinical disease progression.

Plasma cathepsin D correlates with histological classifications of fatty liver disease in adults and responds to intervention

Non-alcoholic steatohepatitis (NASH) is characterized by liver lipid accumulation and inflammation. The mechanisms that trigger hepatic inflammation are poorly understood and subsequently, no specific non-invasive markers exist. We previously demonstrated a reduction in the plasma lysosomal enzyme, cathepsin D (CatD), in children with NASH compared to children without NASH. Recent studies have raised the concept that non-alcoholic fatty liver disease (NAFLD) in adults is distinct from children due to a different histological pattern in the liver. Yet, the link between plasma CatD to adult NASH was not examined. In the current manuscript, we investigated whether plasma CatD in adults correlates with NASH development and regression. Biopsies were histologically evaluated for inflammation and NAFLD in three complementary cohorts of adults (total n = 248). CatD and alanine aminotransferase (ALT) were measured in plasma. Opposite to our previous observations with childhood NASH, we observed increased levels of plasma CatD in patients with NASH compared to adults without hepatic inflammation. Furthermore, after surgical intervention, we found a reduction of plasma CatD compared to baseline. Our observations highlight a distinct pathophysiology between NASH in children and adults. The observation that plasma CatD correlated with NASH development and regression is promising for NASH diagnosis.

Myeloid DLL4 Does Not Contribute to the Pathogenesis of Non-Alcoholic Steatohepatitis in Ldlr-/- Mice

Non-alcoholic steatohepatitis (NASH) is characterized by liver steatosis and inflammation. Currently, the underlying mechanisms leading to hepatic inflammation are not fully understood and consequently, therapeutic options are poor. Non-alcoholic steatohepatitis (NASH) and atherosclerosis share the same etiology whereby macrophages play a key role in disease progression. Macrophage function can be modulated via activation of receptor-ligand binding of Notch signaling. Relevantly, global inhibition of Notch ligand Delta-Like Ligand-4 (DLL4) attenuates atherosclerosis by altering the macrophage-mediated inflammatory response. However, the specific contribution of macrophage DLL4 to hepatic inflammation is currently unknown. We hypothesized that myeloid DLL4 deficiency in low-density lipoprotein receptor knock-out (Ldlr^-/-) mice reduces hepatic inflammation. Irradiated Ldlr^-/- mice were transplanted (tp) with bone marrow from wild type (Wt) or DLL4^f/fLysMCre^+/0 (DLL4^del) mice and fed either chow or high fat, high cholesterol (HFC) diet for 11 weeks. Additionally, gene expression was assessed in bone marrow-derived macrophages (BMDM) of DLL4^f/fLysMCre^WT and DLL4^f/fLysMCre^+/0 mice. In contrast to our hypothesis, inflammation was not decreased in HFC-fed DLL4^del-transplanted mice. In line, in vitro, there was no difference in the expression of inflammatory genes between DLL4-deficient and wildtype bone marrow-derived macrophages. These results suggest that myeloid DLL4 deficiency does not contribute to hepatic inflammation in vivo. Since, macrophage-DLL4 expression in our model was not completely suppressed, it can’t be totally excluded that complete DLL4 deletion in macrophages might lead to different results. Nevertheless, the contribution of non-myeloid Kupffer cells to notch signaling with regard to the pathogenesis of steatohepatitis is unknown and as such it is possible that, DLL4 on Kupffer cells promote the pathogenesis of steatohepatitis.

Metabolic reprogramming & inflammation: Fuelling the host response to pathogens

Successful immune responses to pathogens rely on efficient host innate processes to contain and limit bacterial growth, induce inflammatory response and promote antigen presentation for the development of adaptive immunity. This energy intensive process is regulated through multiple mechanisms including receptor-mediated signaling, control of phago-lysomal fusion events and promotion of bactericidal activities. Inherent macrophage activities therefore are dynamic and are modulated by signals and changes in the environment during infection. So too does the way these cells obtain their energy to adapt to altered homeostasis. It has emerged recently that the pathways employed by immune cells to derive energy from available or preferred nutrients underline the dynamic changes associated with immune activation. In particular, key breakpoints have been identified in the metabolism of glucose and lipids which direct not just how cells derive energy in the form of ATP, but also cellular phenotype and activation status. Much of this comes about through altered flux and accumulation of intermediate metabolites. How these changes in metabolism directly impact on the key processes required for anti-microbial immunity however, is less obvious. Here, we examine the 2 key nutrient utilization pathways employed by innate cells to fuel central energy metabolism and examine how these are altered in response to activation during infection, emphasising how certain metabolic switches or 'reprogramming' impacts anti-microbial processes. By examining carbohydrate and lipid pathways and how the flux of key intermediates intersects with innate immune signaling and the induction of bactericidal activities, we hope to illustrate the importance of these metabolic switches for protective immunity and provide a potential mechanism for how altered metabolic conditions in humans such as diabetes and hyperlipidemia alter the host response to infection.

Pathogenesis of Nonalcoholic Steatohepatitis: Interactions between Liver Parenchymal and Nonparenchymal Cells

Nonalcoholic fatty liver disease (NAFLD) is the most common type of chronic liver disease in the Western countries, affecting up to 25% of the general population and becoming a major health concern in both adults and children. NAFLD encompasses the entire spectrum of fatty liver disease in individuals without significant alcohol consumption, ranging from nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH) and cirrhosis. NASH is a manifestation of the metabolic syndrome and hepatic disorders with the presence of steatosis, hepatocyte injury (ballooning), inflammation, and, in some patients, progressive fibrosis leading to cirrhosis. The pathogenesis of NASH is a complex process and implicates cell interactions between liver parenchymal and nonparenchymal cells as well as crosstalk between various immune cell populations in liver. Lipotoxicity appears to be the central driver of hepatic cellular injury via oxidative stress and endoplasmic reticulum (ER) stress. This review focuses on the contributions of hepatocytes and nonparenchymal cells to NASH, assessing their potential applications to the development of novel therapeutic agents. Currently, there are limited pharmacological treatments for NASH; therefore, an increased understanding of NASH pathogenesis is pertinent to improve disease interventions in the future.

Oxidized LDL at the crossroads of immunity in non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH) is viewed as the hepatic manifestation of the metabolic syndrome and is a condition hallmarked by lipid accumulation in the liver (steatosis) along with inflammation (hepatitis). Currently, the etiology and mechanisms leading to obesity-induced hepatic inflammation are not clear and, as a consequence, strategies to diagnose or treat NASH in an accurate manner do not exist. In the current review, we put forward the concept of oxidized lipids as a significant risk factor for NASH. We will focus on the contribution of the different types of oxidized lipids as part of the oxidized low-density lipoprotein (oxLDL) to the hepatic inflammatory response. Furthermore, we will elaborate on the underlying mechanisms linking oxLDL to inflammatory responses in the liver and on how these cascades can be used as therapeutic targets to combat NASH. This article is part of a Special Issue entitled: Lipid modification and lipid peroxidation products in innate immunity and inflammation edited by Christoph J. Binder.

Alleviation of high-fat diet-induced atherosclerosis and glucose intolerance by a novel GLP-1 fusion protein in ApoE(-/-) mice

We have previously constructed an engineered anti-diabetic fusion protein using glucagon-like peptide-1 and the globular domain of adiponectin. Herein, we evaluated the therapeutic effects of this fusion protein (GAD) on high-fat diet (HFD)-fed ApoE(-/-) mice. The lipid-lowering effect of GAD was determined in C57BL/6 mice using a lipid tolerance test. The effects of GAD on HFD-induced glucose intolerance, atherosclerosis, and hepatic steatosis were evaluated in HFD-fed ApoE(-/-) mice using glucose tolerance test, histological examinations and real-time quantitative PCR. The anti-inflammation activity of GAD was assessed in vitro on macrophages. GAD improved lipid metabolism in C57BL/6 mice. GAD treatment alleviated glucose intolerance, reduced blood lipid level, and attenuated atherosclerotic lesion in HFD-fed ApoE(-/-) mice, which was associated with a repressed macrophage infiltration in the vessel wall. GAD treatment also blocked hepatic macrophage infiltration and prevented hepatic inflammation. GAD suppressed lipopolysaccharide-triggered inflammation responses on macrophages, which can be abolished by H89, an inhibitor of protein kinase A. These findings demonstrate that GAD is able to generate a variety of metabolic benefits in HFD-fed ApoE(-/-) mice and indicate that this engineered fusion protein is a promising lead structure for anti-atherosclerosis drug discovery.

Sialic Acid-Binding Immunoglobulin-like Lectin G Promotes Atherosclerosis and Liver Inflammation by Suppressing the Protective Functions of B-1 Cells

Atherosclerosis is initiated and sustained by hypercholesterolemia, which results in the generation of oxidized LDL (OxLDL) and other metabolic byproducts that trigger inflammation. Specific immune responses have been shown to modulate the inflammatory response during atherogenesis. The sialic acid-binding immunoglobulin-like lectin G (Siglec-G) is a negative regulator of the functions of several immune cells, including myeloid cells and B-1 cells. Here, we show that deficiency of Siglec-G in atherosclerosis-prone mice inhibits plaque formation and diet-induced hepatic inflammation. We further demonstrate that selective deficiency of Siglec-G in B cells alone is sufficient to mediate these effects. Levels of B-1 cell-derived natural IgM with specificity for OxLDL were significantly increased in the plasma and peritoneal cavity of Siglec-G-deficient mice. Consistent with the neutralizing functions of OxLDL-specific IgM, Siglec-G-deficient mice were protected from OxLDL-induced sterile inflammation. Thus, Siglec-G promotes atherosclerosis and hepatic inflammation by suppressing protective anti-inflammatory effector functions of B cells.

Nonalcoholic Fatty Liver Disease and Mean Platelet Volume: A Systemic Review and Meta-analysis

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is linked to obesity, metabolic syndrome, and cardiovascular disease. Increased mean platelet volume (MPV), a marker of platelet activity, is associated with acute myocardial infarction, stroke, thrombosis, and increased mortality after myocardial infarction. The purpose of this study was to perform a meta-analysis to investigate the relationship between NAFLD and MPV.

METHODOLOGY

A systematic search of MEDLINE (Ovid), PubMed, and CINAHL databases from 1950 to May 2014, complemented with manual review of references of published articles for studies comparing MPV in patients with and without NAFLD was done. Results were pooled using both fixed and random effects model.

RESULTS

Our analysis from pooling of data from 8 observational studies including 1428 subjects (NAFLD=842 and non-NAFLD=586) showed that MPV was significantly higher in patients with NAFLD than those without. The standardized mean difference in MPV between NAFLD and controls was 0.457 (95% confidence interval: 0.348-0.565, P<0.001) using fixed and 0.612 (95% confidence interval: 0.286-0.938, P<0.001) using random effects model.

CONCLUSIONS

This study suggests that MPV is significantly higher in patients with NAFLD, indicating the presence of increased platelet activity in such patients. Future research is needed to investigate whether this increased MPV is associated with increased cardiovascular disease in patients with NAFLD.

Research advances in the relationship between nonalcoholic fatty liver disease and atherosclerosis

Nonalcoholic fatty liver disease (NAFLD) is a metabolic stress-induced liver disease that is closely related not only to genetic susceptibility but also to insulin resistance and highly linked with metabolic syndrome. In recent years, the prevalence of NAFLD has increased rapidly, paralleling the epidemic of type 2 diabetes mellitus and obesity leading to cardiovascular disease. It has been demonstrated that NAFLD is highly associated with atherosclerosis. With recently gained knowledge, it appears that NAFLD may induce insulin resistance, dyslipidemia, oxidative stress, inflammation, and fluctuation of adipokines associated with atherosclerosis. In this review, we aimed to summarize recent discoveries related to both NAFLD and atherosclerosis, and to identify possible mechanisms linking them.

Nonalcoholic fatty liver disease and carotid artery atherosclerosis in children and adults: a meta-analysis

Observational studies suggest that nonalcoholic fatty liver disease (NAFLD) is associated with increased carotid intimal medial thickness (C-IMT) and carotid plaques in both children and adults. We carried out a meta-analysis to evaluate the relationship between NAFLD and carotid atherosclerosis measured as C-IMT and carotid plaque prevalence. Medline (Ovid), PubMed, Web of Science, and CINAHL databases were searched from 1946 to September 2014, complemented with a manual review of references of the published articles for studies that compared C-IMT or carotid plaque prevalence in adults and children. Results were pooled using both fixed and random effects models. Of the studies identified, 20 were suitable for testing the effect of NAFLD on C-IMT in adults, 13 for testing the effect of NAFLD on carotid plaque prevalence in adults, and five for testing the effect of NAFLD on C-IMT in the pediatric population. The pooled data from 20 studies (19,274 adult participants: NAFLD=8652, controls=10,622) showed significantly increased C-IMT in patients with NAFLD, compared with controls without NAFLD, according to both fixed [standardized mean difference (SMD)=0.251, 95% confidence interval (CI): 0.220-0.282, P<0.001] and random effects models (SMD=0.944, 95% CI: 0.728-1.160, P<0.001). NAFLD was also found to be associated with a higher carotid artery plaque prevalence when compared with controls, according to both fixed (OR=1.273, 95% CI=1.162-1.394, P<0.001) and random effects models (OR=1.769, 95% CI: 1.213-2.581, P=0.003), on pooling of 13 studies (14,445 adult participants: NAFLD=5399 and controls=9046). Analysis of pooled data from five studies in the pediatric population (1121 pediatric participants: NAFLD=312 and controls=809) also found NAFLD to be associated with significantly increased C-IMT according to fixed (SMD=0.995, 95% CI: 0.840-1.150, P<0.001) and random effects models (1.083, 95% CI: 0.457-1.709, P=0.001). NAFLD is associated with increased C-IMT in both children and adults, and with increased carotid plaque prevalence in adults. Individuals identified with carotid disease should be evaluated for NAFLD and vice versa.

Mechanistic review of drug-induced steatohepatitis

Drug-induced steatohepatitis is a rare form of liver injury known to be caused by only a handful of compounds. These compounds stimulate the development of steatohepatitis through their toxicity to hepatocyte mitochondria; inhibition of beta-oxidation, mitochondrial respiration, and/or oxidative phosphorylation. Other mechanisms discussed include the disruption of phospholipid metabolism in lysosomes, prevention of lipid egress from hepatocytes, targeting mitochondrial DNA and topoisomerase, decreasing intestinal barrier function, activation of the adenosine pathway, increasing fatty acid synthesis, and sequestration of coenzyme A. It has been found that the majority of compounds that induce steatohepatitis have cationic amphiphilic structures; a lipophilic ring structure with a side chain containing a cationic secondary or tertiary amine. Within the last decade, the ability of many chemotherapeutics to cause steatohepatitis has become more evident coining the term chemotherapy-associated steatohepatitis (CASH). The mechanisms behind drug-induced steatohepatitis are discussed with a focus on cationic amphiphilic drugs and chemotherapeutic agents.

Oxidative stress: New insights on the association of non-alcoholic fatty liver disease and atherosclerosis

Non-alcoholic fatty liver disease (NAFLD) represents the most common and emerging chronic liver disease worldwide. It includes a wide spectrum of liver diseases ranging from simple fatty liver to non-alcoholic steatohepatitis (NASH), which may progress to fibrosis and more severe liver complications such as cirrhosis, hepatocellular carcinoma and liver mortality. NAFLD is strongly associated with obesity, insulin resistance, hypertension, and dyslipidaemia, and is now regarded as the liver manifestation of the metabolic syndrome. The increased mortality of patients with NAFLD is primarily a result of cardiovascular disease and, to a lesser extent, to liver related diseases. Increased oxidative stress has been reported in both patients with NAFLD and patient with cardiovascular risk factors. Thus, oxidative stress represents a shared pathophysiological disorder between the two conditions. Several therapeutic strategies targeting oxidative stress reduction in patients with NAFLD have been proposed, with conflicting results. In particular, vitamin E supplementation has been suggested for the treatment of non-diabetic, non-cirrhotic adults with active NASH, although this recommendation is based only on the results of a single randomized controlled trial. Other antioxidant treatments suggested are resveratrol, silybin, L-carnitine and pentoxiphylline. No trial so far, has evaluated the cardiovascular effects of antioxidant treatment in patients with NAFLD. New, large-scale studies including as end-point also the assessment of the atherosclerosis markers are needed.

Amount of hepatic fat predicts cardiovascular risk independent of insulin resistance among Hispanic-American adolescents

Background

Nonalcoholic fatty liver disease (NAFLD) has emerged as the major pediatric chronic liver disease, and it is estimated to affect more than one third of obese children in the U.S. Cardiovascular complications are a leading cause of increased mortality in adults with NAFLD and many adolescents with NAFLD already manifest signs of subclinical atherosclerosis including increased carotid intima-media thickness.

Methods

Volume of intrahepatic fat was assessed in 50 Hispanic-American, overweight adolescents, using Magnetic Resonance Spectroscopy. Lipoprotein compositions were measured using Nuclear Magnetic Resonance.

Results

Plasma triglycerides (TG) (p = 0.003), TG/HDL ratio (p = 0.006), TG/apoB ratio (p = 0.011), large VLDL concentration (p = 0.019), VLDL particle size (p = 0.012), as well as small dense LDL concentration (p = 0.026) progressively increased across higher levels of hepatic fat severity, while large HDL concentration progressively declined (p = 0.043). This pattern of associations remained even after controlling for gender, BMI, visceral fat, and insulin resistance.

Conclusions

Our findings suggest that increased hepatic fat is strongly associated with peripheral dyslipidemia and the amount of fat in the liver may influence cardiovascular risk. Further studies are needed to longitudinally monitor dyslipidemia in children with NAFLD and to examine whether the reduction of hepatic fat would attenuate their long-term CVD risk.

Association of Tumor Necrosis Factor-alpha Polymorphisms and Risk of Coronary Artery Disease in Patients With Non-alcoholic Fatty Liver Disease

BACKGROUND

Cardiovascular events account for the main cause of death in patients with non-alcoholic fatty liver disease (NAFLD), and are largely influenced by genetic factors. Although multiple studies showed that tumor necrosis factor-alpha (TNF-α) polymorphisms are risk factors in the progression of NAFLD, few papers on the association of the polymorphisms and the developing coronary artery disease (CAD) in NAFLD patients have been reported.

OBJECTIVES

The present study was designed to evaluate the association of TNF-α polymorphisms at residues -238 and -308, with the risk of developing CAD in Chinese patients with NAFLD.

PATIENTS AND METHODS

The TNF-α polymorphisms at residues 238 and 308 were genotyped in B-type ultrasonography proven NAFLD patients with (n = 246), without (n = 247) CAD and healthy controls (n = 304), using polymerase chain reaction (PCR). Serum lipid profiles were determined using biochemical methods. Statistical analyses were performed using SPSS statistical software, version 20.0 for Mac.

RESULTS

We found a significant association between TNF-α-238 guanine to alanine (GA) polymorphism and carriers of variant allele A between NAFLD patients with and without CAD (P < 0.05). Carriers of the A allele of TNF-α-238 had higher serum triglycerides (TG) and low density lipoprotein (LDL) levels in NAFLD patients with CAD (P = 0.025 and 0.001, respectively) and a higher TG level in NAFLD patients without CAD (P = 0.017), than their non-carrier counterparts.

CONCLUSIONS

In the Chinese Han population that we studied, NAFLD patients who carry the TNF-α-238 GA polymorphism have an increased risk of developing CAD. Mechanisms underlying this potentially important association require further investigation.

Plasma cathepsin D levels: a novel tool to predict pediatric hepatic inflammation

OBJECTIVES

Nonalcoholic steatohepatitis (NASH) is the most severe form of a hepatic condition known as nonalcoholic fatty liver disease (NAFLD). NASH is histologically characterized by hepatic fat accumulation, inflammation, and ballooning, and eventually coupled with fibrosis that, in turn, may progress to end-stage liver disease even in young individuals. Hence, there is a critical need for specific noninvasive markers to predict hepatic inflammation at an early age. We investigated whether plasma levels of cathepsin D (CatD), a lysosomal protease, correlated with the severity of liver inflammation in pediatric NAFLD.

METHODS

Liver biopsies from children (n=96) with NAFLD were histologically evaluated according to the criteria of Kleiner (NAFLD activity score) and the Brunt's criteria. At the time of liver biopsy, blood was taken and levels of CatD, alanine aminotransferase (ALT), and cytokeratin-18 (CK-18) were measured in plasma.

RESULTS

Plasma CatD levels were significantly lower in subjects with liver inflammation compared with steatotic subjects. Furthermore, we found that CatD levels were gradually reduced and corresponded with increasing severity of liver inflammation, steatosis, hepatocellular ballooning, and NAFLD activity score. CatD levels correlated with pediatric NAFLD disease progression better than ALT and CK-18. In particular, CatD showed a high diagnostic accuracy (area under receiver operating characteristic curve (ROC-AUC): 0.94) for the differentiation between steatosis and hepatic inflammation, and reached almost the maximum accuracy (ROC-AUC: 0.998) upon the addition of CK-18.

CONCLUSIONS

Plasma CatD holds a high diagnostic value to distinguish pediatric patients with hepatic inflammation from children with steatosis.