Hyaluronic acid, an accurate serum marker for severe hepatic fibrosis in patients with non-alcoholic fatty liver disease

Non-invasive Scores and Serum Biomarkers for Fatty Liver in the Era of Metabolic Dysfunction-associated Steatotic Liver Disease (MASLD): A Comprehensive Review From NAFLD to MAFLD and MASLD

PURPOSE OF REVIEW

The prevalence of non-alcoholic fatty liver disease (NAFLD) is rapidly increasing worldwide, making it the leading cause of liver related morbidity and mortality. Currently, liver biopsy is the gold standard for assessing individuals with steatohepatitis and fibrosis. However, its invasiveness, sampling variability, and impracticality for large-scale screening has driven the search for non-invasive methods for early diagnosis and staging. In this review, we comprehensively summarise the evidence on the diagnostic performance and limitations of existing non-invasive serum biomarkers and scores in the diagnosis and evaluation of steatosis, steatohepatitis, and fibrosis.

RECENT FINDINGS

Several non-invasive serum biomarkers and scores have been developed over the last decade, although none has successfully been able to replace liver biopsy. The introduction of new NAFLD terminology, namely metabolic dysfunction-associated fatty liver disease (MAFLD) and more recently metabolic dysfunction-associated steatotic liver disease (MASLD), has initiated a debate on the interchangeability of these terminologies. Indeed, there is a need for more research on the variability of the performance of non-invasive serum biomarkers and scores across the diagnostic entities of NAFLD, MAFLD and MASLD. There remains a significant need for finding valid and reliable non-invasive methods for early diagnosis and assessment of steatohepatitis and fibrosis to facilitate prompt risk stratification and management to prevent disease progression and complications. Further exploration of the landscape of MASLD under the newly defined disease subtypes is warranted, with the need for more robust evidence to support the use of commonly used serum scores against the new MASLD criteria and validation of previously developed scores.

Farnesoid X receptor: From Structure to Function and Its Pharmacology in Liver Fibrosis

The farnesoid X receptor (FXR), a ligand-activated transcription factor, plays a crucial role in regulating bile acid metabolism within the enterohepatic circulation. Beyond its involvement in metabolic disorders and immune imbalances affecting various tissues, FXR is implicated in microbiota modulation, gut-to-brain communication, and liver disease. The liver, as a pivotal metabolic and detoxification organ, is susceptible to damage from factors such as alcohol, viruses, drugs, and high-fat diets. Chronic or recurrent liver injury can culminate in liver fibrosis, which, if left untreated, may progress to cirrhosis and even liver cancer, posing significant health risks. However, therapeutic options for liver fibrosis remain limited in terms of FDA-approved drugs. Recent insights into the structure of FXR, coupled with animal and clinical investigations, have shed light on its potential pharmacological role in hepatic fibrosis. Progress has been achieved in both fundamental research and clinical applications. This review critically examines recent advancements in FXR research, highlighting challenges and potential mechanisms underlying its role in liver fibrosis treatment.

Serologic Biomarkers for Hepatic Fibrosis in Obese Children with Nonalcoholic Steatohepatitis

Purpose

The prevalence of nonalcoholic steatohepatitis (NASH) is increasing with the increasing prevalence of childhood obesity. Although NASH has a high risk of progression to liver fibrosis and cirrhosis, few studies have reported noninvasive markers for predicting hepatic fibrosis in children. This study aimed to evaluate and compare the diagnostic accuracies of serologic biomarkers and scoring systems for hepatic fibrosis in obese children with NASH.

Methods

A total of 96 children were diagnosed with NASH based on liver biopsy findings and divided into two groups according to the degree of liver fibrosis: mild (stage 0-1) or advanced (stage 2-4). Clinical and laboratory parameters and serum levels of hyaluronic acid and type IV collagen were measured. The aspartate aminotransferase/platelet ratio index (APRI) and fibrosis-4 (FIB-4) score were calculated.

Results

Among the noninvasive markers, only serum type IV collagen level and FIB-4 were significantly different between the two groups. The area under the receiver operating curve of each biomarker and scoring system was 0.80 (95% confidence interval [CI]: 0.70-0.90) for type IV collagen at an optimal cutoff of 148 ng/mL (sensitivity 69.8%, specificity 84.6%), followed by 0.69 (95% CI: 0.57-0.83) for APRI, 0.68 (95% CI: 0.56-0.80) for FIB-4, and 0.65 (95% CI: 0.53-0.77) for hyaluronic acid.

Conclusion

Type IV collagen as a single noninvasive serologic biomarker for hepatic fibrosis and FIB-4 as a hepatic fibrosis score are beneficial in predicting advanced hepatic fibrosis and determining proper diagnosis and treatment strategies before fibrosis progresses in obese children with NASH.

The Diagnostic Value of FibroTest and Hepascore as Non-Invasive Markers of Liver Fibrosis in Primary Sclerosing Cholangitis (PSC)

The aim of this study was to evaluate the diagnostic usefulness of two non-invasive, validated, and patented markers of liver fibrosis, the Hepascore and FibroTest, in patients with primary sclerosing cholangitis (PSC). The study group consisted of 74 PSC patients and 38 healthy subjects. All patients had a liver biopsy. The Hepascore and FibroTest were calculated using specific algorithms. The ANOVA rank Kruskal-Wallis test revealed differences in the Hepascore and FibroTest between patients divided according to histological stage (p < 0.001 for both comparisons). The Hepascore and FibroTest had significantly higher results in patients with significant fibrosis (F ≥ 2) in comparison to those with no significant fibrosis (F1) (p < 0.001 for both tests) and higher values in patients with cirrhosis (F4) when compared to those without cirrhosis (F1-F3) (p < 0.001 for both comparisons). The Hepascore test showed a diagnostic sensitivity of 96.8%, a specificity of 100% for fibrosis (at cut-off 0.52) and a diagnostic sensitivity of 95.2%, and a specificity also of 100% for cirrhosis (at 0.80). The FibroTest in point 0.51 for the diagnosis of fibrosis obtained the following values: 58.6%, 90%, 89.5%, and 60%, respectively, and in point 0.73 for the diagnosis of cirrhosis: 42.9%, 100%, 100%, and 45.5, respectively. The Hepascore test reached an excellent diagnostic power in identifying both fibrosis and cirrhosis (AUC = 1.0). The FibroTest and Hepascore are highly valuable for the evaluation of the severity of liver fibrosis and cirrhosis in PSC patients and can be used as a primary screening method, allowing for a significant reduction in the need for liver biopsy. Both markers have the required sensitivity and specificity to detect liver fibrosis and cirrhosis and can be equally used in clinical practice, although the Hepascore seems to be a better test because it is more specific.

Advances in Noninvasive Biomarkers for Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) currently represents one of the most common liver diseases worldwide. Early diagnosis and disease staging is crucial, since it is mainly asymptomatic, but can progress to nonalcoholic steatohepatitis (NASH) or cirrhosis or even lead to the development of hepatocellular carcinoma. Over time, efforts have been put into developing noninvasive diagnostic and staging methods in order to replace the use of a liver biopsy. The noninvasive methods used include imaging techniques that measure liver stiffness and biological markers, with a focus on serum biomarkers. Due to the impressive complexity of the NAFLD's pathophysiology, biomarkers are able to assay different processes involved, such as apoptosis, fibrogenesis, and inflammation, or even address the genetic background and "omics" technologies. This article reviews not only the currently validated noninvasive methods to investigate NAFLD but also the promising results regarding recently discovered biomarkers, including biomarker panels and the combination of the currently validated evaluation methods and serum markers.

An Innovative Electrochemical Immuno-Platform for Monitoring Chronic Conditions Using the Biosensing of Hyaluronic Acid in Human Plasma Samples

Hyaluronic acid (HA) is the main non-sulfated glycosaminoglycan of the extracellular matrix that is synthesized by fibroblasts and other specialized connective tissue cells. The accumulation of HA on different tissues is a characteristic of disorders that are associated with progressive tissue fibrosis. HA is also known to play a critical role in tumorigenesis and tumor metastasis. It is overproduced by many types of tumors and promotes tumor progression and multidrug resistance. There is a great necessity for the development of an easy and cost-effective detection method for the monitoring of HA for both the diagnosis and efficient treatment of related disorders. In the present study, an innovative immune device was designed for the rapid and sensitive recognition of HA in human plasma samples. For this purpose, an efficient alloy (Pt@Au) was fabricated on the surface of the gold electrode. Thus, a novel substrate was used for the preparation of an efficient transducer, which is necessary for the immobilization of biotinylated antibodies. CHA was applied for the electrochemical deposition of Pt@Au nano-alloy on Au electrodes. Additionally, the morphological study of the used nanocomposite was assessed using FESEM at a working voltage of 3 kV, and the chemical structures of the electrode were analyzed using the EDS apparatus. For the first time, a biocompatible alloy-based substrate was prepared for the study of antigen–antibody identification. The developed immunosensor has a linear response within the range of 0.156–160 ng.mL−1 with a limit of detection of 0.039 ng.mL−1 in human plasma samples. This research study offers a novel promising technique for HA analyses and is anticipated to be used in the early diagnosis of some disorders related to abnormal levels of HA in human bio-fluids. Thus, a constructed (pt@Au) nano-alloy provides a useful interface for the dense loading of AB. This excellent design loads high sensations of the biosensor for the selective detection of HA in real samples (human bio-fluids).

Noninvasive biomarkers in pediatric nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease worldwide among children and adolescents. It encompasses a spectrum of disease, from its mildest form of isolated steatosis, to nonalcoholic steatohepatitis (NASH) to liver fibrosis and cirrhosis, or end-stage liver disease. The early diagnosis of pediatric NAFLD is crucial in preventing disease progression and in improving outcomes. Currently, liver biopsy is the gold standard for diagnosing NAFLD. However, given its invasive nature, there has been significant interest in developing noninvasive methods that can be used as accurate alternatives. Here, we review noninvasive biomarkers in pediatric NAFLD, focusing primarily on the diagnostic accuracy of various biomarkers as measured by their area under the receiver operating characteristic, sensitivity, and specificity. We examine two major approaches to noninvasive biomarkers in children with NAFLD. First, the biological approach that quantifies serological biomarkers. This includes the study of individual circulating molecules as biomarkers as well as the use of composite algorithms derived from combinations of biomarkers. The second is a more physical approach that examines data measured through imaging techniques as noninvasive biomarkers for pediatric NAFLD. Each of these approaches was applied to children with NAFLD, NASH, and NAFLD with fibrosis. Finally, we suggest possible areas for future research based on current gaps in knowledge.

The Past, Present, and Future of Noninvasive Test in Chronic Liver Diseases

Chronic liver disease is a major global health threat and is the 11th leading cause of death globally. A liver biopsy is frequently required in assessing the degree of steatosis and fibrosis, information that is important in diagnosis, management, and prognostication. However, liver biopsies have limitations and carry a considerable risk, leading to the development of various modalities of noninvasive testing tools. These tools have been developed in recent years and have improved markedly in diagnostic accuracy. Moving forward, they may change the practice of hepatology.

Non-alcoholic fatty liver disease: Is surgery the best current option and can novel endoscopy play a role in the future?

Over the last decade, non-alcoholic fatty liver disease (NAFLD) has overtaken alcohol as the leading cause of cirrhosis in the Western world. There remains to be a licensed pharmacological treatment for NAFLD. Weight loss is advised for all patients with NAFLD. Many patients however, struggle to lose the recommended weight with lifestyle modification alone. Many drugs have either failed to show significant improvement of steatosis or are poorly tolerated. Bariatric surgery has been shown to reduce liver steatosis and regress liver fibrosis. The pathophysiology is not fully understood, however recent evidence has pointed towards changes in the gut microbiome following surgery. Novel endoscopic treatment options provide a minimally invasive alternative for weight loss. Randomised controlled trials are now required for further clarification.

Long-Term Outcomes Associated with NAFLD, ASCVD, and All-Cause Mortality of Patients with Metabolic Syndrome

Metabolic syndrome (MetS) patients are at higher risk for nonalcoholic fatty liver disease (NAFLD), atherosclerotic cardiovascular diseases (ASCVD), and death. Given a lack of longitudinal data on patients with MetS in Southeast Asia, this study investigated the incidence of NAFLD and ASCVD and the all-cause mortality rate during a 10-year follow-up of Thai patients with MetS. Retrospective data were collected on 496 MetS patients with ultrasonography or transient elastography results. The patients had been followed up continuously by a university hospital between October 2011 and November 2021, and their mean age was 61.0 ± 10.9 years. Patients with secondary causes of hepatic steatosis were excluded. Cox proportional hazards regression models with time-varying covariates were adopted. During the 10-year follow-up, 17 patients (11.2%) developed NAFLD, and 27 (6.4%) developed ASCVD. The NAFLD and ASCVD incidence rates were 21.7 and 10.9 events per 1000 person years, respectively. The mortality rate was 14.2 deaths per 1000 person years. The prevalence of hypertension, dyslipidemia, ASCVD, NAFLD, advanced fibrosis, and cirrhosis at baseline was significantly higher in the nonsurvival group. The NAFLD incidence and mortality rate of patients with MetS were lower than those in previous studies. Intensive, holistic, and continuous care should be considered for better outcomes.

Small fragments of hyaluronan are increased in individuals with obesity and contribute to low-grade inflammation through TLR-mediated activation of innate immune cells

Background and aim

Extracellular matrix (ECM) components released during excessive fat mass expansion are considered potential endogenous danger/alarm signals contributing to innate immune system activation. The aim of the current study was to specifically measure plasma levels of low molecular weight (LMW) hyaluronan (HA) and to evaluate its role as pro-inflammatory damage-associated molecular pattern (DAMP) on leukocyte response in the context of human obesity.

Subjects and methods

Participants were selected according to their body mass index (BMI, kg/m²) as non-obese (BMI < 29.9, n = 18) and obese (BMI > 29.9, n = 33). Plasma samples were size-dependent fractionated using ion-exchange chromatography to specifically obtain LMW HA fractions that were subsequently quantified by ELISA. Cell incubation experiments with synthetic HA molecules were performed on freshly Ficoll-isolated neutrophils (PMN) and peripheral blood monocytes (PBMC). Leukocyte and adipose tissue gene expression was assessed by real-time PCR and NF-κB activation by western blot. Plasma cytokine levels were measured by fluorescent bead-based (Luminex) immunoassay.

Results

We observed a statistically significant increase in the circulating levels of HA fragments of LMW in individuals with obesity which were consistent with significant up-regulated expression of the LMW HA synthesizing enzyme hyaluronan synthase-1 (HAS-1) in obese adipose tissue. Gene expression assessment of HA receptors revealed up-regulated levels for TLR2 in both obese PMN and PBMC. Synthetic HA molecules of different sizes were tested on leukocytes from healthy donors. LMW HA fragments (15–40 kDa) and not those from intermediate molecular sizes (75–350 kDa) induced a significant up-regulation of the expression of major pro-inflammatory cytokines such as IL-1β, MCP-1 and IL-8 in PBMC. Importantly, LMW HA was able to induce the phosphorylation of IKK α/β complex supporting its pro-inflammatory role through NF-κB activation.

Conclusion

Circulating LMW HA molecules are elevated in obesity and may play an important role in triggering low-grade inflammation and the development of metabolic complications.

Influence of liver stiffness heterogeneity on staging fibrosis in patients with nonalcoholic fatty liver disease

BACKGROUND AND AIMS

Despite that hepatic fibrosis often affects the liver globally, spatial distribution can be heterogeneous. This study aimed to investigate the effect of liver stiffness (LS) heterogeneity on concordance between MR elastography (MRE)-based fibrosis staging and biopsy staging in patients with NAFLD.

APPROACH AND RESULTS

We retrospectively evaluated data from 155 NAFLD patients who underwent liver biopsy and 3 Tesla MRE and undertook a retrospective validation study of 169 NAFLD patients at three hepatology centers. Heterogeneity of stiffness was assessed by measuring the range between minimum and maximum MRE-based LS measurement (LSM). Variability of LSM was defined as the stiffness range divided by the maximum stiffness value. The cohort was divided into two groups (homogenous or heterogeneous), according to whether variability was below or above the average for the training cohort. Based on histopathology and receiver operating characteristic (ROC) analysis, optimum LSM thresholds were determined for MRE-based fibrosis staging of stage 4 (4.43, kPa; AUROC, 0.89) and stage ≥3 (3.93, kPa; AUROC, 0.89). In total, 53 had LSM above the threshold for stage 4. Within this group, 30 had a biopsy stage of <4. In 86.7% of these discordant cases, variability of LSM was classified as heterogeneous. In MRE-based LSM stage ≥3, 88.9% of discordant cases were classified as heterogeneous. Results of the validation cohort were similar to those of the training cohort.

CONCLUSIONS

Discordance between biopsy- and MRE-based fibrosis staging is associated with heterogeneity in LSM, as depicted with MRE.

Impact of non-invasive biomarkers on hepatology practice: Past, present and future

Over the last two decades, there have been tremendous advances in the non-invasive diagnosis and risk stratification of chronic liver diseases (CLDs). Non-invasive approaches are based on the quantification of biomarkers in serum samples or on the measurement of liver stiffness, using either ultrasound- or magnetic resonance-based elastography techniques. The fibrosis-4 index (non-patented) and enhanced liver fibrosis test (patented) are the most widely adopted serum markers, whereas vibration-controlled transient elastography is the most widely adopted elastography technique. In this review, we discuss the role of non-invasive tests in the current era, as well as their accuracy and how their use in clinical practice has changed the practice of hepatology, including identification of early cirrhosis in patients with risk factors for CLD, diagnosis of portal hypertension, establishing prognosis in compensated cirrhosis, guiding antiviral treatment, and screening for fibrosis and cirrhosis in primary care.

Prognostic significance of preoperative hyaluronic acid level in patients with hepatocellular carcinoma

BACKGROUND

Serum hyaluronic acid (HA) levels are increased in patients with solid tumors, and may predict outcomes. However, as HA levels also correlate with the degree of liver fibrosis, the prognostic significance of serum HA levels in patients with hepatocellular carcinoma (HCC) is unclear.

METHODS

A total of 656 consecutive patients who underwent hepatic resection for HCC were divided into two groups by serum HA level (high HA [≥200 ng/mL], n = 248; low HA [<200 ng/mL], n = 408). Clinicopathological characteristics and postoperative survival were compared between groups. Moreover, 1:1 propensity score matching analysis was applied to adjust characteristics between groups.

RESULTS

Both the 5-year overall and relapse-free survival rates (OSR and RFSR) in the low HA group were significantly better than those in the high HA group (59.8% vs. 38.6%, respectively, p < 0.001 and 24.5% vs. 13.1%, respectively, p < 0.001). After propensity score matching, two comparable groups of 124 patients each were obtained. However, both the 5-year OSR and RFSR in the low HA group remained significantly better than those in the high HA group (57.4% vs. 38.3%, respectively, p = 0.006 and 22.5% vs. 14.7%, respectively, p = 0.003).

CONCLUSION

High preoperative HA level predicts poor postoperative survival of patients with HCC. undergoing hepatic resection.

Diagnostic Value of Serum Chitinase-3-Like Protein 1 for Liver Fibrosis: A Meta-analysis

Background

Serum chitinase-3-like protein 1 (CHI3L1) is a promising marker for diagnosing liver fibrosis. This meta-analysis was carried out to assess the diagnostic performance of serum CHI3L1 for the estimation of liver fibrosis.

Methods

Systematic searches were performed on PubMed, Embase, Web of Science, Scopus, the Cochrane Library, Google Scholar, Sinomed, the China National Knowledge Infrastructure (CNKI), the Chinese Medical Journal Database, and the Wanfang databases for available studies. The primary studies were screened strictly according to inclusion and exclusion criteria, and sensitivity, specificity, and other measures of accuracy of serum CHI3L1 for evaluating liver fibrosis were pooled with 95% confidence intervals. I² was calculated to assess heterogeneity, and sources of heterogeneity were explored by subgroup analysis. Deeks' test was used to assess for publication bias, and likelihood ratio was used to determine posttest probability.

Results

Our research integrated 11 articles, accounting for 1897 patients older than 18 years old. The pooled sensitivity and specificity for significant fibrosis, advanced fibrosis, and cirrhosis were 0.79 and 0.82 with an area under the receiver operating characteristic curve (AUC) of 0.85, 0.81 and 0.83 with an AUC of 0.91, and 0.72 and 0.74 with an AUC of 0.85, respectively. Random-effects models were used to assess for significant heterogeneity, and subgroup analysis showed that age and aetiology of included patients were likely sources of heterogeneity. No potential publication bias was found for serum CHI3L1 in the diagnosis of significant fibrosis, advanced fibrosis, or cirrhosis, and posttest probability was moderate.

Conclusion

Measurement of serum CHI3L1 is a feasible diagnostic tool for liver fibrosis.

Diagnostic Modalities of Non-Alcoholic Fatty Liver Disease: From Biochemical Biomarkers to Multi-Omics Non-Invasive Approaches

Non-Alcoholic Fatty Liver Disease (NAFLD) is currently the most common cause of chronic liver disease worldwide, and its prevalence is increasing globally. NAFLD is a multifaceted disorder, and its spectrum includes steatosis to steatohepatitis, which may evolve to advanced fibrosis and cirrhosis. In addition, the presence of NAFLD is independently associated with a higher cardiometabolic risk and increased mortality rates. Considering that the vast majority of individuals with NAFLD are mainly asymptomatic, early diagnosis of non-alcoholic steatohepatitis (NASH) and accurate staging of fibrosis risk is crucial for better stratification, monitoring and targeted management of patients at risk. To date, liver biopsy remains the gold standard procedure for the diagnosis of NASH and staging of NAFLD. However, due to its invasive nature, research on non-invasive tests is rapidly increasing with significant advances having been achieved during the last decades in the diagnostic field. New promising non-invasive biomarkers and techniques have been developed, evaluated and assessed, including biochemical markers, imaging modalities and the most recent multi-omics approaches. Our article provides a comprehensive review of the currently available and emerging non-invasive diagnostic tools used in assessing NAFLD, also highlighting the importance of accurate and validated diagnostic tools.

Estimating Drug Efficacy with a Diet-Induced NASH Model in Chimeric Mice with Humanized Livers

Nonalcoholic fatty liver disease/steatohepatitis (NAFLD/NASH) is the most common liver disorder in developed countries. Although many new therapeutics for NASH are present in the drug development pipeline, there are still no approved drugs. One of the reasons that makes NASH drug development challenging is the lack of appropriate animal NASH models that resolve issues arising from inter-species differences between humans and rodents. In the present study, we developed a choline-deficient, L-amino-acid-defined, high-fat-diet (CDAHFD)-induced human NASH model using human liver chimeric mice. We demonstrated human hepatocyte injury by an elevation of plasma human alanine aminotransferase 1 in mice fed CDAHFD. Histological analysis showed that CDAHFD feeding induced similar histological changes to human NASH patients, including ballooning, inflammation, apoptosis, regeneration of human hepatocytes, and pericellular and perisinusoidal fibrosis. The chimeric mice fed CDAHFD were treated with a peroxisome-proliferator-activated receptor α/δ agonist, Elafibranor. Elafibranor ameliorated steatosis, ballooning of hepatocytes, and preserved fibrosis progression. We developed a novel humanized NASH model that can elucidate pathophysiological mechanisms and predict therapeutic efficacy in human NASH. This model will be useful in exploring new drugs and biomarkers in the early stages of human NASH.

Clinical and Molecular Biomarkers for Diagnosis and Staging of NAFLD

Non-alcoholic fatty liver disease (NAFLD) is the most common hepatic pathology in industrialized countries, affecting about 25% of the general population. NAFLD is a benign condition, however, it could evolve toward more serious diseases, including non-alcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and finally, hepatocellular carcinoma (HCC). Liver biopsy is still the gold standard for NAFLD diagnosis. Due to the risks associated with liver biopsy and the impossibility to apply it on a large scale, it is now necessary to identify non-invasive biomarkers, which may reliably identify patients at higher risk of progression. Therefore, several lines of research have tried to address this issue by identifying novel biomarkers using omics approaches, including lipidomics, metabolomics and RNA molecules' profiling. Thus, in this review, we firstly report the conventional biomarkers used in clinical practice for NAFL and NASH diagnosis as well as fibrosis staging, and secondly, we pay attention to novel biomarkers discovered through omics approaches with a particular focus on RNA biomarkers (microRNAs, long-noncoding RNAs), showing promising diagnostic performance for NAFL/NASH diagnosis and fibrosis staging.

Adipose tissue hyaluronan production improves systemic glucose homeostasis and primes adipocytes for CL 316,243-stimulated lipolysis

Plasma hyaluronan (HA) increases systemically in type 2 diabetes (T2D) and the HA synthesis inhibitor, 4-Methylumbelliferone, has been proposed to treat the disease. However, HA is also implicated in normal physiology. Therefore, we generated a Hyaluronan Synthase 2 transgenic mouse line, driven by a tet-response element promoter to understand the role of HA in systemic metabolism. To our surprise, adipocyte-specific overproduction of HA leads to smaller adipocytes and protects mice from high-fat-high-sucrose-diet-induced obesity and glucose intolerance. Adipocytes also have more free glycerol that can be released upon beta3 adrenergic stimulation. Improvements in glucose tolerance were not linked to increased plasma HA. Instead, an HA-driven systemic substrate redistribution and adipose tissue-liver crosstalk contributes to the systemic glucose improvements. In summary, we demonstrate an unexpected improvement in glucose metabolism as a consequence of HA overproduction in adipose tissue, which argues against the use of systemic HA synthesis inhibitors to treat obesity and T2D.

Liver fibrosis is associated with carotid atherosclerosis in patients with liver biopsy-proven nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is related to subclinical atherosclerosis. However, whether the severity of the disease (or which histopathological component) is associated with subclinical atherosclerosis remains controversial. This study aimed to investigate the association between the histopathological severity of NAFLD and carotid intima-media thickness (CIMT) in Japanese patients with liver biopsy-proven NAFLD. Maximum-CIMT (max-CIMT) was measured as an index of carotid atherosclerosis in 195 biopsy-proven NAFLD patients. A significant association was observed between the severity of fibrosis (but not steatosis, inflammation, and ballooning) and max-CIMT. Older age, male gender, hypertension, and advanced fibrosis were independently linked to max-CIMT ≥ 1.2 mm. The prevalence of max-CIMT ≥ 1.2 mm was significantly higher in the advanced fibrosis group than in the non-advanced fibrosis group (75.4% versus 44.0%; p < 0.01). Non-invasive liver fibrosis markers and scoring systems, including fibrosis-4 index, NAFLD fibrosis score, hyaluronic acid, and Wisteria floribunda agglutinin positive Mac-2-binding protein, demonstrated that the diagnostic performance for max-CIMT ≥ 1.2 mm was similar to that of biopsy-based fibrosis staging. In conclusion, advanced fibrosis is significantly and independently associated with high-risk CIMT. Non-invasive fibrosis markers and scoring systems could help estimate the risk of atherosclerosis progression in patients with NAFLD.

Noninvasive Evaluation for Nonalcoholic Fatty Liver Disease and Nonalcoholic Steatohepatitis

PURPOSE

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide and has the potential risk for progressing to nonalcoholic steatohepatitis (NASH), which is associated with a greater risk for complications of chronic liver disease. Noninvasive testing has been evaluated for diagnosis, risk stratification, disease progression, and assessing response to therapy. The purpose of this narrative review was to outline the current noninvasive testing modalities for the diagnostic evaluation of NAFLD and NASH, while discussing possible markers that could be used for monitoring response to therapies.

METHODS

The PubMed and Cochrane databases were searched for relevant articles that evaluated the diagnosis of NAFLD/NASH with serum biomarkers and/or imaging.

FINDINGS

Serum biomarkers, imaging modalities, and combinations/serial algorithms involved in the diagnosis of NAFLD and NASH are outlined. In addition, noninvasive modalities that have been used for assessing response to therapies in clinical trials are discussed.

IMPLICATIONS

Liver biopsy currently remains the gold standard for diagnosis and is often used in clinical trials to assess treatment response. However, developing safe and accessible noninvasive modalities for diagnosis and monitoring will have greater impact and relevance, as biopsy may not always be feasible in all clinical settings.

The Relevance of Noninvasive Tools To Assess Fibrosis in Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a growing cause of chronic liver diseases worldwide, involving about 25% of people. NAFLD incorporates a large spectrum of pathological conditions, from simple steatosis to non-alcoholic steatohepatitis (NASH), cirrhosis and its complications include hepatic decompensation and hepatocellular carcinoma (HCC). This progression occurs, over many years, in an asymptomatic way, until advanced fibrosis appears. Thus, the differentiation of NASH from simple steatosis and identification of advanced hepatic fibrosis are key issues. To date, the histological assessment of fibrosis with liver biopsy is the gold standard, but obviously, invasiveness is the greater threshold. In addition, rare but potentially life-threatening complications, poor acceptability, sampling variability and cost maybe restrict its use. Furthermore, due to the epidemic of NAFLD worldwide and several limitations of liver biopsy evaluation, noninvasive assessment tools to detect fibrosis in NAFLD patients are needed.

Women Have a Lower Risk of Nonalcoholic Fatty Liver Disease but a Higher Risk of Progression vs Men: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

The risk of nonalcoholic fatty liver disease (NAFLD) and its progression may differ between men and women. We conducted a systematic review and meta-analysis to determine the relationship between sex and NAFLD, nonalcoholic steatohepatitis (NASH), and advanced NAFLD fibrosis.

METHODS

Studies reporting sex-stratified NAFLD prevalence among population-based samples and either NASH or advanced fibrosis among patients with biopsy-proven NAFLD were identified from MEDLINE, EMBASE, and Cochrane databases through December 2017. We calculated pooled relative risk ratios comparing women vs men for each outcome.

RESULTS

Our final analysis comprised 54 studies. Samples sizes were 62,239 for the NAFLD analysis, 5428 for the NASH analysis, and 6444 for the advanced fibrosis analysis. Women had a 19% lower risk of NAFLD than men in the general population (pooled risk ratio [RR], 0.81; 95% CI, 0.68-0.97; I² = 97.5%). Women had a similar risk of NASH (RR, 1.00; 95% CI, 0.88-1.14; I² = 85.1%), and a 37% higher risk of advanced fibrosis (RR, 1.37; 95% CI, 1.12-1.68; I² = 74.0%) than men. Age modified the effect of sex on NAFLD severity. Risks of NASH (RR, 1.17; 95% CI, 1.01-1.36) and advanced fibrosis (RR, 1.56; 95% CI, 1.36-1.80; I² = 0) were substantially higher in women in study populations with average ages of 50 years and older; sex differences in NASH and advanced fibrosis were attenuated in younger populations.

CONCLUSIONS

In a systematic review and meta-analysis, we found women to have a lower risk of NAFLD than men. However, once NAFLD is established, women have a higher risk of advanced fibrosis than men, especially after age 50 years.

The Role of Elastography in Non-Alcoholic Fatty Liver Disease

The most common liver disease in developing countries is non-alcoholic fatty liver disease (NAFLD). This involves the abnormal accumulation of lipids in the liver, the pathogenesis of the disease being related to dyslipidemia, obesity, insulin resistance and type 2 diabetes. Most often, the diagnosis of NAFLD is incidental, when performing routine blood tests or when performing a transabdominal ultrasound. The NAFLD spectrum ranges from simple forms of hepatic steatosis to the most advanced form of the disease, steatohepatitis (NASH), which in evolution can cause inflammation, fibrosis, cirrhosis of the liver and even liver cancer. For the evaluation of the prognosis and the clinical evolution, the most important parameter to define is the degree of liver fibrosis. Currently, the gold standard remains the liver biopsy, the differentiation between NAFLD and NASH being made only on the basis of histological analysis. However, liver biopsy is an invasive procedure, with numerous risks such as bleeding, lesions of the other organs and complications related to anesthesia, which significantly reduces its widespread use. Moreover, the risk of a false negative result and the increased costs of the procedure further limits its use in current practice. For this reason, non-invasive methods of evaluating the degree of liver fibrosis have gained ground in recent years. Imaging techniques such as elastography have shown promising results in evaluating and staging NAFLD. The aim of this article is to review the current status of the non-invasive tests for the assessment of NAFLD with a focus on the ultrasound-based elastography techniques.

A New Endemic of Concomitant Nonalcoholic Fatty Liver Disease and Chronic Hepatitis B

Hepatitis B virus (HBV) infection remains a global public problem despite the availability of an effective vaccine. In the past decades, nonalcoholic fatty liver disease (NAFLD) has surpassed HBV as the most common cause of chronic liver disease worldwide. The prevalence of concomitant chronic hepatitis B (CHB) and NAFLD thus reaches endemic proportions in geographic regions where both conditions are common. Patients with CHB and NAFLD are at increased risk of liver disease progression to cirrhosis and hepatocellular carcinoma. Due to the complexity of the pathogenesis, accurate diagnosis of NAFLD in CHB patients can be challenging. Liver biopsy is considered the gold standard for diagnosing and determining disease severity, but it is an invasive procedure with potential complications. There is a growing body of literature on the application of novel noninvasive serum biomarkers and advanced radiological modalities to diagnose and evaluate NAFLD, but most have not been adequately validated, especially for patients with CHB. Currently, there is no approved therapy for NAFLD, although many new agents are in different phases of development. This review provides a summary of the epidemiology, clinical features, diagnosis, and management of the NAFLD and highlights the unmet needs in the areas of CHB and NAFLD coexistence.

Association of novel markers of liver disease with neonatal liver disease in premature baboons, Papio sp

Parenteral Nutrition (PN) Associated Liver Disease (PNALD) affects up to 60% of neonates; however, techniques for diagnosing and monitoring disease progression remain limited. The neonatal baboon model may provide a unique opportunity to identify serologic markers associated with this disease. The purpose of this study was to investigate if Hyaluronic Acid (HA), TIMP metallopeptidase inhibitor 1 (TIMP1), Amino-terminal Propeptide of Type-III Collagen (PIIINP) and Enhanced Liver Fibrosis (ELF) score associate with histological liver disease in neonatal baboons exposed to PN. Preterm baboons delivered via c-section at 67% gestation received PN for 14 days with or without Intralipid (PRT+IL, PRT-IL, respectively) or were sacrificed after birth (PRTCTR). Term baboons were sacrificed after birth (TERMCTR) or survived 14 days (TERM+14d). Serum HA, TIMP1, and PIIINP concentrations were measured by ELISA. A blinded pathologist assigned liver histological scores following necropsy. HA increased 9.1-fold, TIMP1 increased 2.2-fold, and ELF score increased 1.4-fold in PRT-IL compared to PRTCTR. ALT, AST, and GGT were within normal limits and did not vary between groups. A trend towards increased fibrosis was found in PRT-IL baboons. Microvesicular hepatocyte steatosis and Kupffer cell hypertrophy were elevated in PRT-IL vs PRTCTR. HA and TIMP1 were significantly elevated in preterm baboons with early histological findings of liver disease evidenced by hepatic steatosis, Kupffer cell hypertrophy and a trend towards fibrosis whereas traditional markers of liver disease remained normal. These novel markers could potentially be utilized for monitoring early hepatic injury in neonates.

NonInvasive Biomarkers in Nonalcoholic Fatty Liver Disease: Are We There Yet?

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. NAFLD encompasses a spectrum of disease ranging from simple steatosis (NAFL) to nonalcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma. However, despite the growing recognition of this important disease burden, there are significant challenges to accurately and noninvasively diagnose the various forms of NAFLD, especially to differentiate benign steatosis from the progressive NASH. This is of utmost importance because although liver biopsy is considered the current imperfect 'gold' standard for diagnosing NASH and staging fibrosis, it is an invasive procedure with significant limitations. Although, a number of noninvasive markers have been or are currently undergoing investigation, until date, no highly sensitive and specific tests are available to differentiate NASH from simple steatosis. At the moment, further investigations are needed before prediction models or blood-based biomarkers become available and acceptable for routine clinical care. There is a great need for developing inexpensive, easily accessible, highly sensitive and specific biomarkers that permit not only the identification of patients at high risk of adverse outcomes, but also the monitoring of disease progression and response after therapeutic interventions.

Factors influencing subclinical atherosclerosis in patients with biopsy-proven nonalcoholic fatty liver disease

Although the presence of nonalcoholic fatty liver disease (NAFLD) is known to be related to subclinical atherosclerosis, the relationship between the severity of NAFLD and subclinical atherosclerosis is not clear. This study aimed to clarify the factors related to subclinical arteriosclerosis, including the histopathological severity of the disease and PNPLA3 gene polymorphisms, in NAFLD patients. We measured brachial-ankle pulse wave velocity (baPWV) as an index of arterial stiffness in 153 biopsy-proven NAFLD patients. The baPWV values were significantly higher in the advanced fibrosis group than in the less advanced group (median, 1679 cm/s vs 1489 cm/s; p = 5.49×10⁻⁴). Multiple logistic regression analysis revealed that older age (≥55 years) (p = 8.57×10⁻³; OR = 3.03), hypertension (p = 1.05×10⁻³; OR = 3.46), and advanced fibrosis (p = 9.22×10⁻³; OR = 2.94) were independently linked to baPWV ≥1600 cm/s. NAFLD patients were categorized into low-risk group (number of risk factors = 0), intermediate-risk group (= 1), and high-risk group (≥2) based on their risk factors, including older age, hypertension, and biopsy-confirmed advanced fibrosis. The prevalence of baPWV ≥1600 cm/s was 7.1% (3/42) in the low-risk group, 30.8% (12/39) in the intermediate-risk group, and 63.9% (46/72) in the high-risk group. Non-invasive liver fibrosis markers and scores, including the FIB-4 index, NAFLD fibrosis score, hyaluronic acid, Wisteria floribunda agglutinin positive Mac-2-binding protein, and type IV collagen 7s, were feasible substitutes for invasive liver biopsy. Older age, hypertension, and advanced fibrosis are independently related to arterial stiffness, and a combination of these three factors may predict risk of arteriosclerosis in NAFLD patients.

Noninvasive evaluation of nonalcoholic fatty liver disease: Current evidence and practice

With the increasing number of individuals with diabetes and obesity, nonalcoholic fatty liver disease (NAFLD) is becoming increasingly prevalent, affecting one-quarter of adults worldwide. The spectrum of NAFLD ranges from simple steatosis or nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH). NAFLD, especially NASH, may progress to fibrosis, leading to cirrhosis and hepatocellular carcinoma. NAFLD can impose a severe economic burden, and patients with NAFLD-related terminal or deteriorative liver diseases have become one of the main groups receiving liver transplantation. The increasing prevalence of NAFLD and the severe outcomes of NASH make it necessary to use effective methods to identify NAFLD. Although recognized as the gold standard, biopsy is limited by its sampling bias, poor acceptability, and severe complications, such as mortality, bleeding, and pain. Therefore, noninvasive methods are urgently needed to avoid biopsy for diagnosing NAFLD. This review discusses the current noninvasive methods for assessing NAFLD, including steatosis, NASH, and NAFLD-related fibrosis, and explores the advantages and disadvantages of measurement tools. In addition, we analyze potential noninvasive biomarkers for tracking disease processes and monitoring treatment effects, and explore effective algorithms consisting of imaging and nonimaging biomarkers for diagnosing advanced fibrosis and reducing unnecessary biopsies in clinical practice.

Accuracy of non-invasive scoring systems for diagnosing non-alcoholic steatohepatitis-related fibrosis: Multicenter validation study

AIM

Hepatic fibrosis is the most important factor for estimating the prognosis of patients with non-alcoholic fatty liver disease (NAFLD). A novel non-invasive scoring system, the FM-fibro index, showed high accuracy in a pilot study. The purpose of this study was to validate the efficacy of the FM-fibro index in a multicenter cohort.

METHODS

Among 18 institutions, we analyzed 400 Japanese patients with biopsy-proven NAFLD. We evaluated the accuracies of the FM-fibro index, CA-fibro index, and European Liver Fibrosis (ELF) panel by area under the receiver operator characteristics curves (AUROC). The FM-fibro index includes three formulas for type IV collagen 7S, hyaluronic acid, and vascular cell adhesion molecule-1.

RESULTS

Among 400 patients, 205 were women, and the median age was 56 years. The histological distribution of Matteoni types 1, 2, 3, and 4 was 11, 40, 15, and 334, and the distribution of hepatic fibrosis stages 0 to 4 was 67, 183, 55, 63, and 32, respectively. The AUROCs of the FM-fibro index, CA-fibro index, and ELF panel for non-alcoholic steatohepatitis (NASH)-related fibrosis were 0.7178/0.7095/0.7065, 0.7093, and 0.7245, respectively. The sensitivity and specificity of the FM-fibro index for predicting NASH-related fibrosis was 0.5359/0.5210/0.4641 and 0.8333/0.8182/0.8788, respectively. The accuracy of the FM-fibro index was not significantly different from that of the CA-fibro index or the ELF panel.

CONCLUSIONS

The FM-fibro index can predict NASH-related fibrosis with sufficient accuracy compared with previous scoring systems. Further analyses that verify the accuracy of the FM-fibro index to distinguish significant or advanced fibrosis in patients with NAFLD are awaited. (UMIN-CTR: UMIN000018158).

Noninvasive biomarkers in NAFLD and NASH - current progress and future promise

Nonalcoholic fatty liver disease (NAFLD) affects 25% of the global adult population and is the most common chronic liver disease worldwide. Nonalcoholic steatohepatitis (NASH) is the active form of NAFLD, with hepatic necroinflammation and faster fibrosis progression. With an increasing number of patients developing NASH-related end-stage liver disease and pharmacological treatments on the horizon, there is a pressing need to develop NAFLD and NASH biomarkers for prognostication, selection of patients for treatment and monitoring. This requirement is particularly true as liver biopsy utility is limited by its invasive nature, poor patient acceptability and sampling variability. This article reviews current and potential biomarkers for different features of NAFLD, namely, steatosis, necroinflammation and fibrosis. For each biomarker, we evaluate its accuracy, reproducibility, responsiveness, feasibility and limitations. We cover biochemical, imaging and genetic biomarkers and discuss biomarker discovery in the omics era.

Nonalcoholic fatty liver disease: biomarkers as diagnostic tools for liver damage assessment in adult patients from Argentina

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease whose prevalence has been increasing constantly and linked to the global obesity epidemic. The NAFLD histologic spectrum ranges from simple steatosis to nonalcoholic steatohepatitis (NASH), which can progress to cirrhosis and hepatocellular carcinoma. Liver biopsy is the only reliable means to diagnose and stage NASH, but its invasive nature limits its use. Therefore, the prediction of hepatic injury by means of the development of new noninvasive tests represents a growing medical need. Our aim was to evaluate matrix deposition and cell-death markers, which correlate with liver injury in an NAFLD patient cohort.

PATIENTS AND METHODS

Liver biopsies and serum from 34 NAFLD adult patients were analyzed. Histological parameters were evaluated. Matrix deposition [hyaluronic acid (HA) and tissue inhibitor of matrix metalloproteinase inhibitor-1 (TIMP-1)] and cell-death markers [cytokeratin-18 (M65) and caspase-cleaved cytokeratin-18 (M30)] were measured in serum samples.

RESULTS

HA showed an association with fibrosis severity (P=0.03) and M30 with steatosis (P=0.013), inflammation (P=0.004), and fibrosis severity (P=0.04). In contrast, TIMP-1 and M65 showed no association with any histological parameter of liver injury. The evaluation of diagnostic accuracy showed good performance as less invasive markers of significant fibrosis of both HA (area under the receiver operating characteristic curve: 0.928) and M30 (area under the receiver operating characteristic curve: 0.848).

CONCLUSION

Biomarkers are essential tools that may provide a quick and accurate diagnosis for patients with life-threatening NAFLD and NASH. HA and M30, together or determined sequentially, have been found to be straightforward tests that may be sufficient to predict significant fibrosis even in a primary care center of an underdeveloped country.

Adiponectin and the steatosis marker Chi3L1 decrease following switch to raltegravir compared to continued PI/NNRTI-based antiretroviral therapy

BACKGROUND

People with HIV are at for metabolic syndrome (MetS) and fatty liver disease, but the role of Antiretroviral therapy (ART) is poorly understood. MetS and fatty liver disease been associated with changes in adiponectin, soluble ST2 (sST2), chitinase 3-like 1 (Chi3L1), hyaluronic acid (HA), tissue inhibitor of metalloproteinase-1 (TIMP-1), lysyl oxidase-like-2 (LOXL2) and transforming growth factor β (TGF-β) concentrations in HIV-uninfected populations. Protease (PI) and non-nucleoside reverse transcriptase inhibitors (NNRTI) may contribute to these comorbidities, but the effects of switching from PI- or NNRTI to raltegravir (RAL) on these biomarkers is unknown.

METHODS

Cryopreserved plasma was obtained from a completed, prospective trial of HIV-infected women with central adiposity on NNRTI- or PI-based ART during which they were randomized to remain on their current ART or switch to a RAL based regimen. Biomarker concentrations were quantified using ELISA and Multiplex assays at baseline and 24 weeks after randomization. Wilcoxon-signed rank test evaluated within-group changes, Spearman and linear regression models evaluated correlations between biomarkers and clinical covariates.

RESULTS

Participants had a median age of 43 years, CD4+ T lymphocyte count 558 cells/mm3 and BMI 32 kg/m2; 35% met criteria for MetS. At baseline, higher adiponectin levels correlated with higher Chi3L1 levels (r = 0.42, p = 0.02), as did declines after 24 weeks (r = 0.40, p = 0.03). Changes in sST2 correlated with changes in Chi3L1 (r = 0.43, p = 0.02) and adiponectin (r = 0.40, p = 0.03). Adiponectin and Chi3L1 levels decreased significantly in women switched to RAL vs continue PI/NNRTI.

CONCLUSION

In women with HIV and central obesity, the hepatic steatosis/fibrosis marker Chi3L1 and adiponectin decrease in conjunction with sST2 decreases following switch to RAL. Whether switching from NNRTI/PI-based regimens to RAL can improve hepatic steatosis and dysmetabolism requires further study.

TRIAL REGISTRATION

Clinicaltrials.gov NCT00656175.

Serum YKL-40 as a biomarker for liver fibrosis in chronic hepatitis B patients with normal and mildly elevated ALT

Purpose

YKL-40 is a chitinase-like protein expressed in multiple tissues including liver and is reported as a fibrosis marker. This study aimed to determine whether YKL-40 could serve as a diagnostic marker for the assessment of liver fibrosis in chronic hepatitis B patients with normal and mildly elevated ALT.

Methods

Six hundred and eighty-five patients with chronic hepatitis B infection were enrolled in this study from October 2013 to March 2016. All patients underwent liver biopsy and then staged based on Ishak histological system. Serum YKL-40 levels were measured by Human Magnetic Luminex Assays.

Results

Among chronic hepatitis B patients with normal and mildly elevated ALT, almost more than 30% of patients have significant liver fibrosis. Serum YKL-40 levels increased significantly in parallel with the progression of fibrosis in patients with ALT less than two times the upper limit of normal range (P < 0.0001). Multivariate analysis revealed that serum YKL-40, hyaluronic acid, PLT, and AST were independently associated with significant fibrosis. We established a novel YKL-40-based fibrosis model for patients with ALT less than two times the upper limit of normal range (ULN). YKL-40 model was superior to APRI, FIB-4, Forns’ index, and Hui model for diagnosis of significant fibrosis in patients with ALT < 2ULN, with AUROCs of 0.786 [95% confidence interval (CI) 0.726–0.846] in the training group, 0.831 (95%CI 0.752–0.910) in the validation group and 0.801 (95%CI 0.753–0.849) in the entire cohort.

Conclusion

Serum YKL-40 is a feasible biomarker of liver fibrosis in chronic hepatitis B patients. YKL-40 model was superior to APRI, FIB-4, Forns’ index and Hui model for diagnosis of significant fibrosis in patients with normal and mildly elevated ALT.

Electronic supplementary material

The online version of this article (10.1007/s15010-018-1136-2) contains supplementary material, which is available to authorized users.

Hyaluronan in adipogenesis, adipose tissue physiology and systemic metabolism

Hyaluronic acid (HA, also known as hyaluronan), is a non-sulfated linear glycosaminoglycan polymer consisting of repeating disaccharide units of d-glucuronic acid and N-acetyl-d-glucosamine abundantly present in the extracellular matrix. The sizes of hyaluronic acid polymers range from 5000 to 20,000,000 Da in vivo, and the functions of HA are largely dictated by its size. Due to its high biocompatibility, HA has been commonly used as soft tissue filler as well as a major component of biomaterial scaffolds in tissue engineering. Several studies have implicated that HA may promote differentiation of adipose tissue derived stem cells in vitro or in vivo when used as a supporting scaffold. However, whether HA actually promotes adipogenesis in vivo and the subsequent metabolic effects of this process are unclear. This review summarizes some recent publications in the field and discusses the possible directions and approaches for future studies, focusing on the role of HA in the adipose tissue.

Imaging prediction of nonalcoholic steatohepatitis using computed tomography texture analysis

OBJECTIVES

To determine if texture analysis of non-contrast-enhanced CT (NECT) images is able to predict nonalcoholic steatohepatitis (NASH).

METHODS

NECT images from 88 patients who underwent a liver biopsy for the diagnosis of suspected NASH were assessed and texture feature parameters were obtained without and with filtration. The patient population was divided into a predictive learning dataset and a validation dataset, and further divided into groups according to the prediction of liver fibrosis as assessed by hyaluronic acid levels. The reference standard was the histological result of a liver biopsy. A predictive model for NASH was developed using parameters derived from the learning dataset that demonstrated areas under the receiver operating characteristic curve (AUC) of >0.65. The resulting model was then applied to the validation dataset.

RESULTS

In patients without suspected fibrosis, the texture parameter mean without filter and skewness with a 2-mm filter were selected for the NASH prediction model. The AUC of the predictive model for the validation dataset was 0.94 and the accuracy was 94%. In patients with suspicion of fibrosis, the mean without filtration and kurtosis with a 4-mm filter were selected for the NASH prediction model. The AUC for the validation dataset was 0.60 and the accuracy was 42%.

CONCLUSIONS

In patients without suspicion of fibrosis, NECT texture analysis effectively predicted NASH.

KEY POINTS

• In patients without suspicion of fibrosis, NECT texture analysis effectively predicted NASH. • The mean without filtration and skewness with a 2-mm filter were modest predictors of NASH in patients without suspicion of liver fibrosis. • Hepatic fibrosis masks the characteristic texture features of NASH.

Diagnosis and Evaluation of Nonalcoholic Fatty Liver Disease/Nonalcoholic Steatohepatitis, Including Noninvasive Biomarkers and Transient Elastography

The incidence and prevalence of nonalcoholic fatty liver disease (NAFLD) are increasing and identification of people at risk of disease progression is extremely important. The current gold standard for diagnosing NAFLD/nonalcoholic steatohepatitis (NASH) is by liver biopsy, but it has several limitations. Noninvasive tests via biomarkers and transient elastography to assess NAFLD/NASH are being used in clinical practice. The most validated diagnostic panels include the NAFLD fibrosis score, FIB-4 (Fibrosis-4), and FibroMeter. Transient elastography is very useful in evaluating advanced fibrosis and cirrhosis.

High fasting insulin concentrations may be a pivotal predictor for the severity of hepatic fibrosis beyond the glycemic status in non-alcoholic fatty liver disease patients before development of diabetes mellitus

BACKGROUND

Insulin resistance and type 2 diabetes mellitus (T2DM) contribute to the progression of non-alcoholic fatty liver disease (NAFLD). However, the relationship between glucose metabolic factors and the histological severity in NAFLD patients before development of T2DM is not well known.

METHODS

In 103 biopsy-proven NAFLD patients (68 men and 35 women) with hemoglobin A1c of <6.5% and fasting blood glucose of <126 mg/dL, we investigated whether glucose metabolic factors influenced the severity of hepatic fibrosis without prior known T2DM.

RESULTS

Female gender, age, serum aspartate aminotransferase, the aspartate aminotransferase/alanine aminotransferase ratio, fasting immunoreactive insulin (f-IRI), homeostasis model assessment - insulin resistance, hemoglobin A1c, hyaluronic acid, and type IV collagen 7 s were significantly higher, and 1,5-anhydroglucitol was significantly lower, in the fibrosis stage F3 group than in the F0-2 group. Multiple logistic regression analysis showed that only f-IRI (P = 0.006; odds ratio, 1.15151; 95% confidence interval, 1.04198-1.27254) was significantly indicated as a predictive factor for F3. As determined by both forward and backward stepwise selection analyses to optimize the model, f-IRI (P = 0001; odds ratio, 1.16788) remained an independent predictive factor for F3. To discriminate the F3 group from the F0-2 group, the area under the receiver operating characteristic curves showed that fasting insulin was 0.7219, and the best cut-off value of f-IRI was 13.2 μU/mL in the receiver operating characteristic curve analysis.

CONCLUSIONS

High fasting insulin concentrations may be a pivotal glucose metabolic predictor for the severity of hepatic fibrosis beyond the glycemic status in NAFLD patients before development of T2DM.

Machine-learning-based classification of real-time tissue elastography for hepatic fibrosis in patients with chronic hepatitis B

Hepatic fibrosis is a common middle stage of the pathological processes of chronic liver diseases. Clinical intervention during the early stages of hepatic fibrosis can slow the development of liver cirrhosis and reduce the risk of developing liver cancer. Performing a liver biopsy, the gold standard for viral liver disease management, has drawbacks such as invasiveness and a relatively high sampling error rate. Real-time tissue elastography (RTE), one of the most recently developed technologies, might be promising imaging technology because it is both noninvasive and provides accurate assessments of hepatic fibrosis. However, determining the stage of liver fibrosis from RTE images in a clinic is a challenging task. In this study, in contrast to the previous liver fibrosis index (LFI) method, which predicts the stage of diagnosis using RTE images and multiple regression analysis, we employed four classical classifiers (i.e., Support Vector Machine, Naïve Bayes, Random Forest and K-Nearest Neighbor) to build a decision-support system to improve the hepatitis B stage diagnosis performance. Eleven RTE image features were obtained from 513 subjects who underwent liver biopsies in this multicenter collaborative research. The experimental results showed that the adopted classifiers significantly outperformed the LFI method and that the Random Forest(RF) classifier provided the highest average accuracy among the four machine algorithms. This result suggests that sophisticated machine-learning methods can be powerful tools for evaluating the stage of hepatic fibrosis and show promise for clinical applications.

Nonalcoholic fatty liver disease: Diagnostic biomarkers

Nonalcoholic fatty liver disease is a common medical condition worldwide and its prevalence has increased notably in the past few years due to the increases in prevalence of obesity and metabolic syndrome. However, diagnosis of this disease is still a matter of debate because of disease variations and pathophysiologic alterations. Specific single markers have gained considerable attention recently, among them markers related to hepatic pathophysiology, inflammation, adipocytokines and so forth. But, it seems that no single marker is sufficient for diagnosis and staging of the disease, and applying a panel including different types of tests may be more useful.

Invasive and non-invasive assessment of portal hypertension

Portal hypertension is the central driver of complications in patients with chronic liver diseases and cirrhosis. The diagnosis of portal hypertension has important prognostic and clinical implications. In particular, screening for varices in patients with portal hypertension can effectively reduce the morbidity and mortality of variceal bleeding. In this article, we review the invasive and non-invasive methods to assess portal hypertension. Hepatic venous pressure gradient remains the gold standard to measure portal pressure but is invasive and seldom performed outside expert centers and research settings. In recent years, a number of non-invasive tests of fibrosis have shown good correlation with liver histology. They also show promise in identifying patients with portal hypertension and large varices. As a result, the latest Baveno VI consensus guidelines endorse the use of liver stiffness measurement by transient elastography and platelet count as initial assessment to select patients for varices screening. On the other hand, the performance of non-invasive tests in assessing the response to non-selective beta-blockers or transjugular intrahepatic portosystemic shunting is either suboptimal or unclear.

Late graft hepatitis and fibrosis in pediatric liver allograft recipients: Current concepts and future developments

Liver transplantation (LT) in children now has a 20-year survival of >80%, but the longterm outcome of these grafts remains uncertain. Serial protocol liver biopsies after transplantation from several pediatric centres have demonstrated the gradual development of unexplained graft inflammation ("idiopathic" posttransplant hepatitis; IPTH) and graft fibrosis in biopsies obtained >12 months post-LT in children with good graft function and (near) normal liver biochemistry. Although the clinical significance of these findings is uncertain, there is evidence to suggest that IPTH may be a form of rejection or chronic antibody-mediated rejection as it is associated with the presence of auto/alloantibodies; de novo Class II donor-specific HLA antibodies (DSA); previous episodes of rejection, and may improve or be prevented with increased immunosuppression. Currently, the only method of diagnosing either hepatitis or fibrosis has been by serial protocol biopsies as neither serum markers of fibrosis nor noninvasive methods to detect fibrosis such as transient elastography (TE) are sufficiently validated in children. This review will focus on the diagnosis and management of idiopathic posttransplant hepatitis and graft fibrosis, discuss current methods for detecting graft injury, and potential mechanisms for their development. Liver Transplantation 22 1593-1602 2016 AASLD.

Serum hyaluronic acid predicts protein-energy malnutrition in chronic hepatitis C

Serum hyaluronic acid (HA) is a well-established marker of fibrosis in patients with chronic liver disease (CLD). However, the relationship between serum HA level and protein-energy malnutrition (PEM) in patients with CLD is an unknown. We aimed to examine the relationship between serum HA level and PEM in patients with chronic hepatitis C (CHC) compared with the relationships of other serum markers of fibrosis. A total of 298 CHC subjects were analyzed. We defined patients with serum albumin level of ≤3.5 g/dL and nonprotein respiratory quotient <0.85 using indirect calorimetry as having PEM. We investigated the effect of serum HA level on the presence of PEM. Receiver operating characteristic curve (ROC) analysis was performed for calculating the area under the ROC (AUROC) for serum HA level, platelet count, aspartate aminotransferase (AST) to platelet ratio index, FIB-4 index, AST to alanine aminotransferase ratio, and Forns index for the presence of PEM. The median serum HA level in this study was 148.0 ng/mL (range: 9.0-6340.0 ng/mL). In terms of the degree of liver function (chronic hepatitis, Child-Pugh A, B, and C), the analyzed patients were well stratified according to serum HA level (overall significance, P < 0.0001). The median value (range) of serum HA level in patients with PEM (n = 61) was 389.0 ng/mL (43.6-6340.0 ng/mL) and that in patients without PEM (n = 237) was 103.0 ng/mL (9.0-783.0 ng/mL) (P < 0.0001). Among 6 fibrosis markers, serum HA level yielded the highest AUROC with a level of 0.849 at an optimal cut-off value of 151.0 ng/mL (sensitivity 93.4%; specificity 62.0%; P < 0.0001). In the multivariate analysis, serum HA level was found to be a significant prognostic factor related to the presence of PEM (P = 0.0001).In conclusion, serum HA level can be a useful predictor of PEM in patients with CHC.

Fibrosis Assessment in Nonalcoholic Fatty Liver Disease (NAFLD) in 2016

Nonalcoholic fatty liver disease (NAFLD) is a spectrum of liver pathologies characterized by hepatic steatosis with a history of little to no alcohol consumption or secondary causes of hepatic steatosis. The prevalence of NAFLD is 20-25 % of the general population in the Western countries and is associated with metabolic risk factors such as obesity, diabetes mellitus, and dyslipidemia. The spectrum of disease ranges from simple steatosis to nonalcoholic steatohepatitis, fibrosis, and cirrhosis. Advanced fibrosis is the most significant predictor of mortality in NAFLD. It is crucial to assess for the presence and degree of hepatic fibrosis in order to make therapeutic decisions and predict clinical outcomes. Liver biopsy, the current gold standard to assess the liver fibrosis, has a number of drawbacks such as invasiveness, sampling error, cost, and inter-/intra-observer variability. There are currently available a number of noninvasive tests as an alternative to liver biopsy for fibrosis staging. These noninvasive fibrosis tests are increasingly used to rule out advanced fibrosis and help guide disease management. While these noninvasive tests perform relatively well for ruling out advanced fibrosis, they also have limitations. Understanding the strengths and limitations of liver biopsy and the noninvasive tests is necessary for deciding when to use the appropriate tests in the evaluation of patients with NAFLD.

Non-invasive diagnostic approach to non-alcoholic fatty liver disease: current evidence and future perspectives

Non-alcoholic fatty liver disease is a new epidemic liver disease, thus, its early diagnosis and the identification of those patients with the worst prognosis is mandatory. Liver biopsy is still the diagnostic gold standard, even if it is associated to a significant rate of complications; moreover, the interpretation of histological samples is not always univocal. Several non-invasive alternative scores have been proposed for the diagnostic approach to non-alcoholic fatty liver disease. This article evaluates the performance of the currently available non-invasive diagnostic strategies. The authors also suggest a potential diagnostic algorithm, with two or more non-invasive techniques, to increase the overall accuracy for identifying patients with worst prognosis, and to minimize the recourse to liver biopsy.

Performance of non-invasive models of fibrosis in predicting mild to moderate fibrosis in patients with non-alcoholic fatty liver disease

BACKGROUND & AIMS

In non-alcoholic fatty liver disease, presence of fibrosis is predictive of long-term liver-related complications. Currently, there are no reliable and non-invasive means of quantifying fibrosis in those with non-alcoholic fatty liver disease. Therefore, we aimed to evaluate the performance of a panel of non-invasive models in predicting fibrosis in non-alcoholic fatty liver disease.

METHODS

The accuracy of FibroMeter non-alcoholic fatty liver disease, fibrosis 4 and four other non-invasive models in predicting fibrosis in those with biopsy proven non-alcoholic fatty liver disease was compared. These models were constructed post hoc in patients who had necessary clinical information collected within 2 months of a liver biopsy. The areas under receiver operating characteristics curves were compared for each model using Delong analysis. Optimum cut-off for each model and fibrosis stage were calculated using the Youden index.

RESULTS

The area under receiver operating characteristics curves for F ≥ 1 fibrosis for fibrosis 4 and FibroMeter non-alcoholic fatty liver disease was 0.821 and 0.801 respectively. For F ≥ 3, the area under receiver operating characteristics curves was 0.866 for fibrosis 4 and 0.862 for FibroMeter non-alcoholic fatty liver disease. Delong analysis showed the area under receiver operating characteristics curves was statistically different for fibrosis 4 and FibroMeter non-alcoholic fatty liver disease compared with BARD, BAAT and aspartate aminotransferase:alanine aminotransferase ratio for F ≥ 1 and F ≥ 3. Area under receiver operating characteristics curves were significantly different for fibrosis 4 and FibroMeter non-alcoholic fatty liver disease for F ≥ 3 compared with non-alcoholic fatty liver disease fibrosis score. At a fixed sensitivity of 90%, FibroMeter non-alcoholic fatty liver disease had the highest specificity for F ≥ 1 (52.4%) and F ≥ 3 (63.8%). In contrast, at a fixed specificity of 90%, fibrosis 4 outperformed other models with a sensitivity of 60.2% for F ≥ 1 and 70.6% for F ≥ 3 fibrosis.

CONCLUSION

These non-invasive models of fibrosis can predict varying degrees of fibrosis from routinely collected clinical information in non-alcoholic fatty liver disease.

Therapeutic effect of renin angiotensin system inhibitors on liver fibrosis

Background and objective:

Currently, there is no effective therapy available for liver fibrosis. This study aims to evaluate the efficacy of renin angiotensin system inhibitors on liver fibrosis.

Method:

Full-text randomized controlled trials in patients with liver fibrosis were identified and included in the meta-analysis. The primary outcome measure was the histological fibrosis score of the liver. Secondary outcome measures included fibrosis area of the liver, serological levels of fibrosis markers, adverse events, and withdrawals.

Results:

From 6973 non-duplicated entries by systematic search, four randomized controlled trials with 210 patients were identified. The renin angiotensin system inhibitors therapy resulted in a marginally significant reduction in liver fibrosis score (MD = -0.30; 95% CI: -0.62–0.02, p = 0.05) and a significant reduction in liver fibrosis area (MD = -2.36%; 95% CI: -4.22%–-0.50%, p = 0.01) as compared with control. The therapy was well tolerated and there was no significant difference in withdrawals between treatment and control groups (RD = 0.00; 95% CI: -0.06–0.06, p = 0.97).

Conclusions:

Renin angiotensin system inhibitor therapy results in a reduction in liver fibrosis score and liver fibrosis area in patients with hepatic fibrosis with good safety profile. However, randomized controlled trials of high-quality will clarify the effectiveness of renin angiotensin system inhibitors on liver fibrosis.

Hyaluronic acid as a biomarker of fibrosis in chronic liver diseases of different etiologies

Chronic liver diseases represent a significant public health problem worldwide. The degree of liver fibrosis secondary to these diseases is important, because it is the main predictor of their evolution and prognosis.

Hyaluronic acid is studied as a non-invasive marker of liver fibrosis in chronic liver diseases, in an attempt to avoid the complications of liver puncture biopsy, considered the gold standard in the evaluation of fibrosis. We review the advantages and limitations of hyaluronc acid, a biomarker, used to manage patients with chronic viral hepatitis B or C infection, non-alcoholic fatty liver disease, HIV-HCV coinfection, alcoholic liver disease, primary biliary cirrhosis, biliary atresia, hereditary hemochromatosis and cystic fibrosis.