The association between adipocytokines and biomarkers for nonalcoholic fatty liver disease-induced liver injury: a study in the general population

Population screening for liver fibrosis: Toward early diagnosis and intervention for chronic liver diseases

Cirrhosis, highly prevalent worldwide, develops after years of hepatic inflammation triggering progressive fibrosis. Currently, the main etiologies of cirrhosis are non-alcoholic fatty liver disease and alcohol-related liver disease, although chronic hepatitis B and C infections are still major etiological factors in some areas of the world. Recent studies have shown that liver fibrosis can be assessed with relatively high accuracy noninvasively by serological tests, transient elastography, and radiological methods. These modalities may be utilized for screening for liver fibrosis in at-risk populations. Thus far, a limited number of population-based studies using noninvasive tests in different areas of the world indicate that a significant percentage of subjects without known liver disease (around 5% in general populations and a higher rate -18% to 27%-in populations with risk factors for liver disease) have significant undetected liver fibrosis or established cirrhosis. Larger international studies are required to show the harms and benefits before concluding that screening for liver fibrosis should be applied to populations at risk for chronic liver diseases. Screening for liver fibrosis has the potential for changing the current approach from diagnosing chronic liver diseases late when patients have already developed complications of cirrhosis to diagnosing liver fibrosis in asymptomatic subjects providing the opportunity of preventing disease progression.

Interplay between non-alcoholic fatty liver disease and cardiovascular risk in an asymptomatic general population

BACKGROUND AND AIMS

Non-alcoholic fatty liver (NAFLD) is a major cause of liver disease worldwide leading also to a higher risk of cardiovascular events. We aimed to evaluate the impact of fatty liver and fibrosis on cardiovascular risk in a general population.

METHODS

Five hundred and forty-two subjects included in the community-based ABCD (Alimentazione, Benessere Cardiovascolare e Diabete) study were recruited. Steatosis (controlled attenuation parameter > 288 dB/m) and severe fibrosis (low risk, liver stiffness measurement [LSM] < 7.9 KPa with M probe and < 5.7 KPa with XL probe; intermediate risk, LSM 7.9-9.5 KPa with M probe and 5.7-9.2 KPa with XL probe; high risk, LSM ≥ 9.6 KPa with M probe and ≥ 9.3 KPa with XL probe) were assessed with FibroScan. Cardiovascular risk was evaluated by the atherosclerotic cardiovascular disease (ASCVD) risk estimator and defined low if < 5%, borderline if 5-7.4%, intermediate if 7.5-19.9% and high if ≥ 20%. Intima-media thickness (IMT) was measured with ultrasound.

RESULTS

Prevalence of steatosis and of severe fibrosis in this cohort was 31.7% and 4.8%, respectively. ASCVD score was evaluated in patients with and without steatosis and according to the risk of severe fibrosis. By ordinal regression analysis, both steatosis (odds ratio [OR] 1.62, 95% confidence interval [CI] 1.13-2.33, P = 0.009) and severity of fibrosis (OR 1.67, 95% CI 1.18-2.36, P = 0.003) were independent risk factors for a higher ASCVD risk after adjusting for obesity. Subjects with NAFLD, when compared with those without, did not differ for IMT (0.75 vs 0.72 mm; P = 0.11) and IMT ≥ 1 mm (15.6% vs 12.1%; P = 0.24). Higher prevalence of IMT ≥ 1 mm was found in patients at high or intermediate risk of severe fibrosis (24% and 28.6%, respectively) compared with those at low risk (12.1%) (P = 0.03); this association was maintained after adjusting for confounders (OR 2.70, 95% CI 1.01-2.86, P = 0.04).

CONCLUSION

In the setting of a general adult population, the presence of NAFLD and severe fibrosis are associated with to a higher cardiovascular risk profile, pointing towards the need for specific preventive measures.

Adiponectin, Leptin, and IGF-1 Are Useful Diagnostic and Stratification Biomarkers of NAFLD

Background: Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease where liver biopsy remains the gold standard for diagnosis. Here we aimed to evaluate the role of circulating adiponectin, leptin, and insulin-like growth factor 1 (IGF-1) levels as non-invasive NAFLD biomarkers and assess their correlation with the metabolome. Materials and Methods: Leptin, adiponectin, and IGF-1 serum levels were measured by ELISA in two independent cohorts of biopsy-proven obese NAFLD patients and healthy-liver controls (discovery: 38 NAFLD, 13 controls; validation: 194 NAFLD, 31 controls) and correlated with clinical data, histology, genetic parameters, and serum metabolomics. Results: In both cohorts, leptin increased in NAFLD vs. controls (discovery: AUROC 0.88; validation: AUROC 0.83; p < 0.0001). The leptin levels were similar between obese and non-obese healthy controls, suggesting that obesity is not a confounding factor. In the discovery cohort, adiponectin was lower in non-alcoholic steatohepatitis (NASH) vs. non-alcoholic fatty liver (AUROC 0.87; p < 0.0001). For the validation cohort, significance was attained for homozygous for PNPLA3 allele c.444C (AUROC 0.63; p < 0.05). Combining adiponectin with specific serum lipids improved the assay performance (AUROC 0.80; p < 0.0001). For the validation cohort, IGF-1 was lower with advanced fibrosis (AUROC 0.67, p < 0.05), but combination with international normalized ratio (INR) and ferritin increased the assay performance (AUROC 0.81; p < 0.01). Conclusion: Serum leptin discriminates NAFLD, and adiponectin combined with specific lipids stratifies NASH. IGF-1, INR, and ferritin distinguish advanced fibrosis.

Efficacy and Safety of GLP-1 Receptor Agonists in Patients With Type 2 Diabetes Mellitus and Non-Alcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis

The prevalence of non-alcoholic fatty liver disease (NAFLD) in patients with type 2 diabetes mellitus (T2DM) is increasing and there is an urgent need for new treatment strategy to prevent progression of hepatic steatosis and fibrosis. We have performed a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the efficacy and safety of glucagon-like peptide-1 receptor agonists (GLP-1RAs) in the treatment of hepatic steatosis and fibrosis in patients with T2DM and NAFLD. The PubMed, Web of Science, Scopus, Embase and Cochrane Central Register of Controlled Trials databases were searched for articles that met the eligibility criteria to explore the efficacy and safety of GLP-1RAs in patients with T2DM and NAFLD. We assessed pooled data using a random/fixed-effects model according to the I² and p-values. Eight trials that included a total of 468 participants were eligible for inclusion in the review. For primary outcomes, administration of GLP-1RAs significantly decreased the content of intrahepatic adipose (IHA)[p=0.007, weight mean difference (WMD) -3.01, 95% confidence interval (CI) -4.75, -1.28], subcutaneous adipose tissue (SAT) (p<0.00001,WMD -28.53,95%CI -68.09,-26.31), and visceral adipose tissue (VAT) (p<0.0001,WMD -29.05,95%CI -42.90,-15.9). For secondary outcomes, GLP-1RAs produced a significant decrease in levels of alanine aminotransferase(ALT)(p=0.02, WMD -3.82, 95%CI -7.04, -0.60), aspartate aminotransferase (AST) (p=0.03, WMD -2.4, 95%CI -4.55,-0.25, I² = 49%), body weight (p<0.00001,WMD -3.48,95%CI -4.58,-2.37), body mass index (p<0.00001,WMD -1.07,95%CI -1.35,-0.78), circumference waist (p=0.0002,WMD -3.87, 95%CI -5.88, -1.86) fasting blood glucose (p=0.02, WMD -0.35, 95%CI -0.06, -0.05), HbA_1c (p<0.00001,WMD -0.39,95%CI -0.56,-0.22), HoMA-IR(p=0.005, WMD-1.51, 95%CI-0.87,-0.16), total cholesterol (p=0.0008, WMD -0.31, 95%CI -0.48, 0.13) and triglycerides (p=0.0008, WMD -0.27, 95%CI -0.43,-0.11) in comparison with the control regimens. The main adverse events associated with GLP-1RAs included mild-to-moderate gastrointestinal discomfort and nonsense hypoglycemia that resolved within a few weeks. GLP-1RAs were an effective treatment that improved intrahepatic visceral and subcutaneous adipose tissue, inflammatory markers, the anthropometric profiles and some metabolic indices in patients with T2DM and NAFLD, GLP-1RAs could be considered for use in these if there are no contraindications. Further studies are needed to understand the direct and indirect effects of GLP-1RAs on NAFLD and the potential mechanism via which they prevent its progression. Systematic Review Registration: PROSPERO, identifier CRD42021265806.

Prevalence of liver fibrosis in an unselected general population with high prevalence of obesity and diabetes mellitus. Time for screening?

INTRODUCTION

Cirrhosis and liver cancer are currently common causes of death worldwide. The global epidemic of obesity has increased the incidence of nonalcoholic fatty liver disease (NAFLD) and cirrhosis in recent years. Advanced fibrosis increases the morbimortality rate in NAFLD. The Mexican population has one of the highest prevalence of obesity and diabetes mellitus (DM) worldwide.

AIM

To determine the prevalence of advanced liver fibrosis in Mexican general population.

METHODS

Adult individuals, without a history of liver disease nor heavy alcohol consumption were randomly sampled from 20,919 participants of a health and nutrition survey applied to the general population. Clinical and laboratory evaluations were performed to calculate the NAFLD fibrosis score (NFS) (an extensively validated non-invasive method). Two cut-off points were used. Advanced fibrosis was defined as a result >0.676.

RESULTS

In total 695 individuals were included. The mean age was 47.8±16.4. The majority were between 20 and 50 years (59%), 70.2% were female, 35.5% showed obesity and 15.8% DM. The 93% had normal serum ALT. Based on the NFS results, 56 individuals (8.1%) had a high probability of fibrosis. Most patients from this subgroup showed normal serum ALT (92.9%), 89.3% were >45yr. old, 52% were obese and 27% suffered from DM.

CONCLUSIONS

Based on these results, 8.1% of Mexican general population without a history of liver disease is at high risk of having advanced liver fibrosis and complications and death derived from cardiovascular disease and cirrhosis. Most of them showed normal ALT serum levels.

Atrial Fibrillation and Heart Failure With Preserved Ejection Fraction in Patients With Nonalcoholic Fatty Liver Disease

The most common causes of chronic liver disease in the developed world-nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH)-are the hepatic manifestations of an insulin-resistant state that is linked to visceral adiposity and systemic inflammation. NAFLD and NASH lead to an expansion of epicardial adipose tissue and the release of proinflammatory adipocytokines that cause microcirculatory dysfunction and fibrosis of the adjoining myocardium, resulting in atrial fibrillation as well as heart failure with a preserved ejection fraction (HFpEF). Inflammatory changes in the left atrium lead to electroanatomical remodeling; thus, NAFLD and NASH markedly increase the risk of atrial fibrillation. Simultaneously, patients with NAFLD or NASH commonly show diastolic dysfunction or latent HFpEF. Interventions include 1) weight loss by caloric restriction, bariatric surgery, or intensive exercise, and 2) drugs that ameliorate fat-mediated inflammation in both the liver and heart (eg, statins, metformin, sodium-glucose cotransporter 2 inhibitors, glucagon-like peptide-1 receptor agonists, and pioglitazone). Patients with NAFLD or NASH commonly have an inflammation-related atrial and ventricular myopathy, which may contribute to symptoms and long-term outcomes.

Organokines in disease

Studies have linked obesity, metabolic syndrome, type 2 diabetes, cardiovascular disease (CVD), nonalcoholic fatty liver disease (NAFLD) and dementia. Their relationship to the incidence and progression of these disease states suggests an interconnected pathogenesis involving chronic low-grade inflammation and oxidative stress. Metabolic syndrome represents comorbidities of central obesity, insulin resistance, dyslipidemia, hypertension and hyperglycemia associated with increased risk of type 2 diabetes, NAFLD, atherosclerotic CVD and neurodegenerative disease. As the socioeconomic burden for these diseases has grown signficantly with an increasing elderly population, new and alternative pharmacologic solutions for these cardiometabolic diseases are required. Adipose tissue, skeletal muscle and liver are central endocrine organs that regulate inflammation, energy and metabolic homeostasis, and the neuroendocrine axis through synthesis and secretion of adipokines, myokines, and hepatokines, respectively. These organokines affect each other and communicate through various endocrine, paracrine and autocrine pathways. The ultimate goal of this review is to provide a comprehensive understanding of organ crosstalk. This will include the roles of novel organokines in normal physiologic regulation and their pathophysiological effect in obesity, metabolic syndrome, type 2 diabetes, CVD, NAFLD and neurodegenerative disorders.

Prevalence and severity of nonalcoholic fatty liver disease by transient elastography: Genetic and metabolic risk factors in a general population

BACKGROUND & AIMS

The worldwide spread of obesity is leading to a dramatic increase in the prevalence of nonalcoholic fatty liver disease (NAFLD) and its complications. We aimed to evaluate both prevalence and factors associated with NAFLD in a general population in a Mediterranean area.

METHODS

We considered 890 consecutive individuals included in the community-based ABCD (Alimentazione, Benessere Cardiovascolare e Diabete) study (ISRCTN15840340). Controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) were measured with FibroScan. Participants were genotyped for PNPLA3 rs738409 and TM6SF2 rs58542926 variants.

RESULTS

The prevalence of NAFLD in the cohort was 48%. NAFLD participants exhibited elevated LSM values, suggesting advanced fibrosis (6.5% of cases). Both NAFLD and advanced fibrosis were independently associated with traditional risk factors (NAFLD: age >50 years, obesity, hypertension, elevated ALT and low HDL-cholesterol serum concentrations. Advanced fibrosis: IFG/diabetes, elevated ALT serum concentrations). A high prevalence (>60%) of NAFLD was found in obese people, while it varied widely in non-obese people according to the presence of metabolic risk factors. PNPLA3 G variant (OR = 1.33, 95% C.I. = 1.01-1.8; P < .05) was independently associated with NAFLD. Prevalence of advanced fibrosis (high LSM values) ranged from 3.4% (no risk factors) to 60% (presence of all risk factors). TM6SF2 T variant (OR = 3.06, 95% C.I. = 1.08-8.65, P < .05) was independently associated with advanced fibrosis (high LSM values).

CONCLUSIONS

In a cohort of a general population, the prevalence of NAFLD was very high, and among NAFLD patients a significant proportion had advanced fibrosis (high LSM values). Apart from traditional risk factors, genetic factors may have a significant role that needs to be further investigated.

Current Concepts in Pediatric Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) represents a spectrum of disease. Its increasing prevalence is a direct result of historically high rates of obesity. Hepatocyte lipid accumulation is the first step in a cascade of metabolic and inflammatory events thought to precipitate NAFLD. Histologic findings provide insight into these events. Lifestyle modification remains the primary therapy in children. Current recommendations include vitamin E treatment in those with biopsy-proven NASH. Trials of novel drugs are ongoing in adults. As efficacy/safety are established, these therapies may be tenable for use in children. At the current time, biopsy-driven histology endpoints are necessary to establish whether future therapies can improve pediatric or adult-type NASH in children.

Cord Blood Adipokines and Lipids and Adolescent Nonalcoholic Fatty Liver Disease

CONTEXT

Maternal adiposity in pregnancy is associated with offspring adiposity and metabolic dysfunction postnatally, including greater risk of nonalcoholic fatty liver disease (NAFLD). Recent genetic analyses suggest a causal effect of greater maternal body mass index on offspring birth weight and ponderal index, but the relative roles of the environment in utero or later in life remains unclear.

OBJECTIVE

We sought to determine whether markers of infant adiposity (birth weight, umbilical cord blood leptin, adiponectin, and lipids) were associated with markers of NAFLD in adolescence.

DESIGN, SETTING, AND PARTICIPANTS

This was a UK prospective birth cohort with 17 years of follow-up with liver function tests (aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltransferase) (n = 1037 participants), and ultrasound scan assessed liver fat, volume, and sheer velocity at age 17 (n = 541 participants). Missing covariate data were imputed.

MAIN OUTCOMES

Ultrasound and biochemical measures of NAFLD were measured.

RESULTS

Birth weight, cord blood leptin, and adiponectin were not associated with a diagnosis of NAFLD. In adjusted analyses, 2 of 42 associations attained conventional 5% levels of significance. Birth weight was positively associated with liver volume (1.0% greater per 100 g [95% confidence interval 0.5%-2.0%]). Cord high-density lipoprotein-cholesterol was positively associated with alanine aminotransferase (11.6% higher per 1 mmol/L [95% confidence interval 0.3, 23.4]); however, this association was primarily mediated via offspring adiposity.

CONCLUSIONS

In this extensive analysis, we found little evidence measurements of infant fat mass and birth size were related to adolescent markers of NAFLD. The association between birth weight and adolescent liver volume may indicate the contribution of greater organ size to birth weight and tracking of organ size.

Awareness of the severity of liver disease re-examined using software-combined biomarkers of liver fibrosis and necroinflammatory activity

BACKGROUND

Effective antiviral treatment (direct-acting antiviral agents (DAAs)), the requirement for a fibrosis score to support DDA reimbursement and a screening strategy, such as the USA baby boomer campaign, should lead to an increased awareness of liver disease severity.

OBJECTIVE

To compare the awareness of liver disease severity between the USA and France, two countries with similar access to hepatitis C virus (HCV) and hepatitis B virus (HBV) treatments, similar rules for treatment reimbursement and similar availability of validated fibrosis tests, but with different policies, as France has no screening.

METHOD

The global database of the FibroTest-ActiTest, including 1,085,657 subjects between 2002 and 2014, was retrospectively analysed. Awareness was defined as the test prescription rate and was compared between the USA and France, according to year of birth, gender and dates of DAA availability and screening campaign (2013-2014).

RESULTS

In the USA 252,688 subjects were investigated for HCV, with a dramatic increase (138%) in the test rate in 2013-2014 (119,271) compared with 2011-2012 (50,031). In France 470,762 subjects were investigated (subjects with HCV and other disease) and the rates were stable. In USA 82.4% of subjects and in France 84.6% were classified as either the highest or lowest priority. The most striking difference was the higher test rate in women born between 1935 and 1944 in France 30,384/200,672 (15.1%) compared with the USA 8035/97,079 (8.3%) (OR=1.98 (95% CI 1.93 to 2.03) p<0.0001). This resulted in twice as many cases of cirrhosis being detected, 2.6% (5191/200,672 women) and 1.3% (1303/97,079), respectively, despite the same prevalence of cirrhosis in this age group (17.1% vs 16.2%) and without any clear explanation as to why they had not been included in the USA screening.

CONCLUSIONS

This study highlighted in the USA the association between awareness of liver disease and both the HCV campaign and DAA availability. In comparison with France, there was a dramatically lower awareness of cirrhosis in the USA for women born between 1935 and 1944.

HCV genotype 3 and squamous cell carcinoma antigen (SCCA)-IgM are independently associated with histological features of NASH in HCV-infected patients

Nonalcoholic steatohepatitis (NASH) enhances the risk of progressive liver disease. In chronic hepatitis C (CHC), liver steatosis is frequent, especially in genotype 3, but its clinical significance is debated. As squamous cell carcinoma antigen (SCCA)-IgM has been associated with advanced liver disease and risk of tumour development, we evaluated its occurrence in CHC and the possible relation with NASH at liver biopsy. Using a validated ELISA, serum SCCA-IgM was measured in 91 patients with CHC at the time of liver biopsy performed before antiviral treatment, at the end of treatment and 6 months thereafter, and in 93 HCV-negative patients with histological diagnosis of nonalcoholic fatty liver disease, as controls. SCCA-IgM was detected in 33% of CHC patients and in 4% of controls. This biomarker was found more elevated in CHC patients with histological NASH, and at multivariate analysis, SCCA-IgM and HCV genotype 3 were independently associated with NASH [OR (95% CI): 6.94 (1.21-40) and 27.02 (4.44-166.6)]. As predictors of NASH, HCV genotype 3 and SCCA-IgM had a specificity and a sensitivity of 97% and 44%, and of 95% and 27%, respectively. PPV and NPV were 80% and 86% for HCV genotype 3 vs 73% and 72% for SCCA-IgM. In patients with sustained virologic response to therapy, SCCA-IgM levels decreased significantly, while these remained unchanged in nonresponders. In conclusion, SCCA-IgM is detectable in one-third of patients with CHC and significantly correlates with histological NASH.

Direct targeting of risk factors significantly increases the detection of liver cirrhosis in primary care: a cross-sectional diagnostic study utilising transient elastography

OBJECTIVES

To assess the feasibility of a novel diagnostic algorithm targeting patients with risk factors for chronic liver disease in a community setting.

DESIGN

Prospective cross-sectional study.

SETTING

Two primary care practices (adult patient population 10,479) in Nottingham, UK.

PARTICIPANTS

Adult patients (aged 18 years or over) fulfilling one or more selected risk factors for developing chronic liver disease: (1) hazardous alcohol use, (2) type 2 diabetes or (3) persistently elevated alanine aminotransferase (ALT) liver function enzyme with negative serology.

INTERVENTIONS

A serial biomarker algorithm, using a simple blood-based marker (aspartate aminotransferase:ALT ratio for hazardous alcohol users, BARD score for other risk groups) and subsequently liver stiffness measurement using transient elastography (TE).

MAIN OUTCOME MEASURES

Diagnosis of clinically significant liver disease (defined as liver stiffness ≥8 kPa); definitive diagnosis of liver cirrhosis.

RESULTS

We identified 920 patients with the defined risk factors of whom 504 patients agreed to undergo investigation. A normal blood biomarker was found in 62 patients (12.3%) who required no further investigation. Subsequently, 378 patients agreed to undergo TE, of whom 98 (26.8% of valid scans) had elevated liver stiffness. Importantly, 71/98 (72.4%) patients with elevated liver stiffness had normal liver enzymes and would be missed by traditional investigation algorithms. We identified 11 new patients with definite cirrhosis, representing a 140% increase in the number of diagnosed cases in this population.

CONCLUSIONS

A non-invasive liver investigation algorithm based in a community setting is feasible to implement. Targeting risk factors using a non-invasive biomarker approach identified a substantial number of patients with previously undetected cirrhosis.

TRIAL REGISTRATION NUMBER

The diagnostic algorithm utilised for this study can be found on clinicaltrials.gov (NCT02037867), and is part of a continuing longitudinal cohort study.

Adiponectin: A multitasking player in the field of liver diseases

Adiponectin is the most abundant adipokine synthesized by adipose tissue and has been shown to be a key component in the relationship between adiposity, insulin resistance and inflammation. It circulates in plasma at physiological concentrations that represent 0.05% of all plasma proteins. Adiponectin has trimeric, hexameric and multimeric forms that bind to receptors AdipoR1, AdipoR2 and T-cadherin especially in liver, muscle and endothelial cells. Adiponectin is considered a potent modulator of lipid and glucose metabolism with antidiabetic, antiatherogenic and anti-inflammatory properties, and plays an important role in the pathogenesis of metabolic diseases. The hepatoprotective effects of adiponectin, especially in non-alcoholic fatty liver disease (NAFLD), have been widely investigated, and its antisteatotic, anti-inflammatory and antifibrogenic effects have already been described. Adiponectin levels are reduced in individuals with fatty liver disease independently of body mass index, insulin resistance and other adipokines, and are inversely related to the severity of steatosis and necroinflammation, suggesting an important role in the relationship between adipose tissue, the liver and insulin sensitivity. Adiponectin has also been found to be reduced in cases of hepatitis B and C infection, and in cholestatic and autoimmune diseases, but is increased in patients with cirrhosis of different aetiologies. In addition, an important role for the liver in the regulation of adiponectin secretion by adipocytes, mediated by bile acids, has recently been proposed. The present report describes the importance of adiponectin in hepatic diseases as well as some future perspectives of the role of adiponectin as a biomarker and therapeutic target in liver diseases.

Limited value of plasma cytokeratin-18 as a biomarker for NASH and fibrosis in patients with non-alcoholic fatty liver disease

BACKGROUND & AIMS

Liver biopsy is the only reliable way of diagnosing and staging NASH but its invasive nature limits its use. Plasma caspase-generated cytokeratin-18 fragments (CK-18) have been proposed as a non-invasive alternative. We studied its clinical value in a large multiethnic NAFLD population and examined its relationship to clinical/metabolic/histological parameters.

METHODS

424 middle-aged subjects in whom we measured adipose tissue, liver and muscle insulin resistance (IR), liver fat by MRS (n=275) and histology (n=318).

RESULTS

Median CK-18 were elevated in patients with vs. without NAFLD by MRS (209 [IQR: 137-329] vs. 122 [IQR: 98-155]U/L) or with vs. without NASH (232 [IQR: 151-387] vs. 170 [IQR: 135-234]U/L, both p<0.001). Plasma CK-18 raised significantly with any increase in steatosis, inflammation and fibrosis, but there was a significant overlap across disease severity. The CK-18 AUROC to predict NAFLD, NASH or fibrosis were 0.77 (95% CI=0.71-0.84), 0.65 (95% CI=0.59-0.71) and 0.68 (95% CI=0.61-0.75), respectively. The overall sensitivity/specificity for NAFLD, NASH and fibrosis were 63% (57-70%)/83% (69-92%), 58% (51-65%)/68% (59-76%) and 54% (44-63%)/85% (75-92%), respectively. CK-18 correlated most strongly with ALT (r=0.57, p<0.0001) and adipose tissue IR (insulin-suppression of FFA: r=-0.43; p<0.001), less with steatosis, lobular inflammation and fibrosis (r=0.28-0.34, all p<0.001), but not with ballooning, BMI, metabolic syndrome or T2DM.

CONCLUSIONS

Plasma CK-18 has a high specificity for NAFLD and fibrosis, but its limited sensitivity makes it inadequate as a screening test for staging NASH. Whether combined as a diagnostic panel with other biomarkers or clinical/laboratory tests may prove useful requires further study.

Cytokeratin 18, alanine aminotransferase, platelets and triglycerides predict the presence of nonalcoholic steatohepatitis

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is one of the critical public health problems in China. The full spectrum of the disease ranges from simple steatosis and nonalcoholic steatohepatitis (NASH) to cirrhosis and hepatocellular carcinoma(HCC). The infiltration of inflammatory cells characterizes NASH. This characteristic contributes to the progression of hepatitis, fibrosis, cirrhosis, and HCC. Therefore, distinguishing NASH from NAFLD is crucial.

OBJECTIVE AND METHODS

Ninety-five patients with NAFLD, 44 with NASH, and 51 with non-NASH were included in the study to develop a new scoring system for differentiating NASH from NAFLD. Data on clinical and biological characteristics, as well as blood information, were obtained. Cytokeratin-18 (CK-18) fragments levels were measured using an enzyme-linked immunosorbant assay.

RESULTS

Several indexes show significant differences between the two groups, which include body mass index (BMI), waist-on-hip ratio (WHR), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), γ-glutamyl transpeptidase (γ-GT), platelets, uric acid (UA), hs-C-reactive protein (hs-CRP), triglycerides (TG), albumin (ALB), and CK-18 fragments (all P < 0.05). The CK-18 fragment levels showed a significant positive correlation with steatosis severity, ballooning, lobular inflammation, and fibrosis stage (all P < 0.05). Therefore, a new model that combines ALT, platelets, CK-18 fragments, and TG was established by logistic regression among NAFLD patients. The AUROC curve in predicting NASH was 0.920 (95% CI: 0.866 - 0.974, cutoff value = 0.361, sensitivity = 89%, specificity = 86%, positive predictive value = 89%, negative predictive value = 89%).

CONCLUSION

The novel scoring system may be considered as a useful model in predicting the presence of NASH in NAFLD patients.

The liver and the kidney: two critical organs influencing the atherothrombotic risk in metabolic syndrome

The increased atherothrombotic risk in patients with metabolic syndrome (MetS) has been classically explained by the multiplicative effect of systemic concomitant pro-atherosclerotic factors. In particular, centripetal obesity, dyslipidaemia, glucose intolerance, hypertension (differently combined in the diagnosis of the disease) would be expected to act as classical cardiovascular risk conditions underlying accelerated atherogenesis. In order to better understand specific atherosclerotic pathophysiology in MetS, emerging evidence focused on the alterations in different organs that could serve as both pathophysiological targets and active players in the disease. Abnormalities in adipose tissue, heart and arteries have been widely investigated in a variety of basic research and clinical studies in MetS. In this narrative review, we focus on pathophysiological activities of the liver and kidney. Considering its key role in metabolism and production of soluble inflammatory mediators (such as C-reactive protein [CRP]), the liver in MetS has been shown to be altered both in its structure and function. In particular, a relevant amount of the fat accumulated within this organ has been shown to be associated with different degrees of inflammation and potential insulin resistance. In humans, non-alcoholic fatty liver disease (NAFLD) has been described as the hepatic manifestation of MetS. In an analogous manner, epidemiological evidence strongly suggested a "guilty" association between MetS and chronic kidney disease (CKD). Some biomarkers of hepatic (such as C-reactive protein, TNF-alpha or other cytokines) and renal diseases (such as uric acid) associated with MetS might be particularly useful to better manage and prevent the atherothrombotic risk.

Artemisia scoparia extract attenuates non-alcoholic fatty liver disease in diet-induced obesity mice by enhancing hepatic insulin and AMPK signaling independently of FGF21 pathway

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD) is a common liver disease which has no standard treatment. In this regard, we sought to evaluate the effects of extracts of Artemisia santolinaefolia (SANT) and Artemisia scoparia (SCO) on hepatic lipid deposition and cellular signaling in a diet-induced obesity (DIO) animal model.

MATERIALS/METHODS

DIO C57/B6J mice were randomly divided into three groups, i.e. HFD, SANT and SCO. Both extracts were incorporated into HFD at a concentration of 0.5% (w/w). Fasting plasma glucose, insulin, adiponectin, and FGF21 concentrations were measured.

RESULTS

At the end of the 4-week intervention, liver tissues were collected for analysis of insulin, AMPK, and FGF21 signaling. SANT and SCO supplementation significantly increased plasma adiponectin levels when compared with the HFD mice (P<0.001). Fasting insulin levels were significantly lower in the SCO than HFD mice, but not in SANT group. Hepatic H&E staining showed fewer lipid droplets in the SCO group than in the other two groups. Cellular signaling data demonstrated that SCO significantly increased liver IRS-2 content, phosphorylation of IRS-1, IR β, Akt1 and Akt2, AMPK α1 and AMPK activity and significantly reduced PTP 1B abundance when compared with the HFD group. SCO also significantly decreased fatty acid synthase (FAS), HMG-CoA Reductase (HMGR), and Sterol regulatory element-binding protein 1c (SREBP1c), but not Carnitine palmitoyltransferase I (CPT-1) when compared with HFD group. Neither SANT nor SCO significantly altered plasma FGF21 concentrations and liver FGF21 signaling.

CONCLUSION

This study suggests that SCO may attenuate liver lipid accumulation in DIO mice. Contributing mechanisms were postulated to include promotion of adiponectin expression, inhibition of hepatic lipogenesis, and/or enhanced insulin and AMPK signaling independent of FGF21 pathway.

In vitro and in vivo models of non-alcoholic fatty liver disease (NAFLD)

By now, non-alcoholic fatty liver disease (NAFLD) is considered to be among the most common liver diseases world-wide. NAFLD encompasses a broad spectrum of pathological conditions ranging from simple steatosis to steatohepatitis, fibrosis and finally even cirrhosis; however, only a minority of patients progress to end-stages of the disease, and the course of the disease progression to the later stages seems to be slow, developing progressively over several years. Key risk factors including overweight, insulin resistance, a sedentary life-style and an altered dietary pattern, as well as genetic factors and disturbances of the intestinal barrier function have been identified in recent years. Despite intense research efforts that lead to the identification of these risk factors, knowledge about disease initiation and molecular mechanisms involved in progression is still limited. This review summarizes diet-induced and genetic animal models, as well as cell culture models commonly used in recent years to add to the understanding of the mechanisms involved in NAFLD, also referring to their advantages and disadvantages.

Adiponectin: a key playmaker adipocytokine in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome and can progress to cirrhosis, liver failure, and hepatocellular carcinoma. In the last two decades, the prevalence of NAFLD has been growing in most developed countries, mainly as a consequence of its close association with obesity and diabetes mellitus. The exact pathogenesis of NAFLD and especially the mechanisms leading to disease progression have not been completely understood. Adipocytes produce and secrete several bioactive substances known as adipocytokines which are implicated in the pathogenesis of the disease. Among them, adiponectin is an insulin-sensitizing adipocytokine possessing multiple beneficial effects on obesity-related medical complication. This review focuses on the role of adiponectin in NAFLD pathogenesis and its potential use as a diagnostic tool but also as therapeutic target for NAFLD management.