Exportin 4 DNA promoter methylation in liver fibrosis.

A role for exportin 4 (XPO4) in the pathogenesis of liver fibrosis was recently identified. We sought to determine changes in hepatic XPO4 promoter methylation levels during liver fibrosis. The quantitative real-time RT-PCR technique was used to quantify the mRNA level of XPO4. Additionally, pyrosequencing was utilized to assess the promoter methylation status of XPO4. The methylation rate of the XPO4 promoter was significantly increased with fibrosis in human and mouse models, while XPO4 mRNA expression negatively correlated with methylation of its promoter. DNA methyltransferases (DNMTs) levels (enzymes that drive DNA methylation) were upregulated in patients with liver fibrosis compared to healthy controls and in hepatic stellate cells upon transforming growth factor beta (TGFß) stimulation. The DNA methylation inhibitor 5-Aza or specific siRNAs for these DNMTs led to restoration of XPO4 expression. The process of DNA methylation plays a crucial role in the repression of XPO4 transcription in the context of liver fibrosis development.

Micro-elimination of chronic hepatitis C virus in mental health settings: A prospective multicentre pragmatic trial.

INTRODUCTION: Hepatitis C virus (HCV) prevalence is high in the mental health population. We sought to evaluate testing and treatment uptake for HCV following the implementation of a universal nurse led study in inpatient and outpatient mental health populations. METHODS: From January 2018 to December 2020, we screened mental health inpatients (n = 322) and community mental health patients (n = 615) for HCV with either specialist hepatology nurses or mental health nurses (mental health nurse). RESULTS: 75.5% (464/615) of community patients and 100% (322/322) of inpatients consented to screening, with an HCV antibody-positive prevalence of 12.7% (59/464) in community patients and 19.6% (63/322) in inpatients. RNA detectable prevalence was 4.0% (22/464) and 7.5% (24/322), respectively. Community patients who were screened by specialist hepatology nurses were more likely to consent to screening (94.4% vs. 45.7%, p < 0.001) but had lower proportion of HCV antibody (10.5% vs. 20.3%, p < 0.001) and RNA detectable (4.0% vs. 7.5%, p = 0.018) when compared to mental health nurse screening. Engagement with treatment was 27.0% of community mental health patients and 45.8% of mental health inpatients undergoing treatment. All patients undergoing treatment and underwent sustained viral response (SVR) testing achieved SVR. DISCUSSION AND CONCLUSIONS: Universal screening of HCV using a nurse-led model has high rates of success in mental health patients with high proportions undergoing screening, with no reduction in the rates of SVR achieved with DAA therapy compared to the general population. Further work is needed to bridge the gap between identification of HCV and treatment among mental health patients.

Validity and Impact of Methods for Collecting Training Data for Myoelectric Prosthetic Control Algorithms.

Intuitive regression control of prostheses relies on training algorithms to correlate biological recordings to motor intent. The quality of the training dataset is critical to run-time regression performance, but accurately labeling intended hand kinematics after hand amputation is challenging. In this study, we quantified the accuracy and precision of labeling hand kinematics using two common training paradigms: 1) mimic training, where participants mimic predetermined motions of a prosthesis, and 2) mirror training, where participants mirror their contralateral intact hand during synchronized bilateral movements. We first explored this question in healthy non-amputee individuals where the ground-truth kinematics could be readily determined using motion capture. Kinematic data showed that mimic training fails to account for biomechanical coupling and temporal changes in hand posture. Additionally, mirror training exhibited significantly higher accuracy and precision in labeling hand kinematics. These findings suggest that the mirror training approach generates a more faithful, albeit more complex, dataset. Accordingly, mirror training resulted in significantly better offline regression performance when using a large amount of training data and a non-linear neural network. Next, we explored these different training paradigms online, with a cohort of unilateral transradial amputees actively controlling a prosthesis in real-time to complete a functional task. Overall, we found that mirror training resulted in significantly faster task completion speeds and similar subjective workload. These results demonstrate that mirror training can potentially provide more dexterous control through the utilization of task-specific, user-selected training data. Consequently, these findings serve as a valuable guide for the next generation of myoelectric and neuroprostheses leveraging machine learning to provide more dexterous and intuitive control.

Global prevalence of MAFLD-related hepatocellular carcinoma: A systematic review and meta-analysis.

BACKGROUND & AIMS: The global proportion of hepatocellular carcinoma (HCC) attributable to metabolic dysfunction-associated fatty liver disease (MAFLD) is unclear. The MAFLD diagnostic criteria allows objective diagnosis in the presence of steatosis plus defined markers of metabolic dysfunction, irrespective of concurrent liver disease. We aimed to determine the total global prevalence of MAFLD in HCC cohorts (total-MAFLD), including the proportion with MAFLD as their sole liver disease (single-MAFLD), and the proportion of those with concurrent liver disease where MAFLD was a contributary factor (mixed-MAFLD). METHODS: This systematic review and meta-analysis included studies systematically ascertaining MAFLD in HCC cohorts, defined using international expert panel criteria including ethnicity specific BMI cut-offs. A comparison of clinical and tumour characteristics was performed between single-MAFLD, mixed-MAFLD and non-MAFLD HCC. RESULTS: 22 studies (56,565 individuals with HCC) were included. Total and single-MAFLD HCC prevalence was 48.7% (95% CI; 34.5% - 63.0%) and 12.4% (95% CI; 8.3% - 17.3%), respectively. In HCC due to chronic hepatitis B, C and alcohol-related liver disease, mixed-MAFLD prevalence was 40.0% (95% CI; 30.2% - 50.3%), 54.1% (95% CI; 40.4% - 67.6%) and 64.3% (95% CI; 52.7% - 75.0%), respectively. Mixed-MAFLD HCC had significantly higher likelihood of cirrhosis and lower likelihood of metastatic spread compared to single-MAFLD HCC, and a higher platelet count and lower likelihood of macrovascular invasion compared to non-MAFLD HCC. CONCLUSION: MAFLD is common as a sole aetiology, but more so and as a co-factor in mixed-aetiology HCC, supporting the use of a positive diagnostic criteria.

Efficacy of Trimetazidine in the Prevention of Contrast-Induced Nephropathy in Patients Undergoing Contrast Coronary Intervention: A Systematic Review and Meta-Analysis (PRISMA).

Objective: The present systematic review assessed the efficacy of peri-procedurally administered trimetazidine in the prevention of contrast-induced nephropathy (CIN) in patients undergoing coronary interventions with contrast agents. Methods: We performed a systematic literature review of articles published in PubMed and Google Scholar by 7 December 2023 and included articles from the last 15 years that evaluated the efficacy of trimetazidine in preventing CIN in cardiac patients undergoing coronary intervention. Results: After title/abstract and full-text screening, this systematic review included 9 randomized controlled trials (N = 2158 patients) with two groups: Trimetazidine (60-70 mg/day 24 to 48 h before and up to 72 h after the procedure) with hydration and the control group with only hydration. A total of 234/2158 patients developed CIN (Incidence rate [IR], 10.8%) as per the CIN definition of the Contrast Media Safety Committee of the European Society of Urogenital Radiology. The incidence of CIN in the trimetazidine vs. control group was 6.4% (69/1083) vs. 15.4% (165/1075), and the odds ratio (95% CI) was 0.3753 (0.279-0.504). Conclusions: In conclusion, the trimetazidine group had a lower incidence of CIN. Trimetazidine offers a reno-protective effect and helps in reducing the CIN incidence in patients undergoing cardiac intervention. Peri-procedure administration of trimetazidine significantly decreases the risk of CIN in patients despite comorbidities.

Hepatitis C Virus Antiviral Drug Resistance and Salvage Therapy Outcomes Across Australia.

Background: Hepatitis C virus (HCV) infection can now be cured with well-tolerated direct-acting antiviral (DAA) therapy. However, a potential barrier to HCV elimination is the emergence of resistance-associated substitutions (RASs) that reduce the efficacy of antiviral drugs, but real-world studies assessing the clinical impact of RASs are limited. Here, an analysis of the impact of RASs on retreatment outcomes for different salvage regimens in patients nationally who failed first-line DAA therapy is reported. Methods: We collected data from 363 Australian patients who failed first-line DAA therapy, including: age, sex, fibrosis stage, HCV genotype, NS3/NS5A/NS5B RASs, details of failed first-line regimen, subsequent salvage regimens, and treatment outcome. Results: Of 240 patients who were initially retreated as per protocol, 210 (87.5%) achieved sustained virologic response (SVR) and 30 (12.5%) relapsed or did not respond. The SVR rate for salvage regimens that included sofosbuvir/velpatasvir/voxilaprevir was 94.3% (n = 140), sofosbuvir/velpatasvir 75.0% (n = 52), elbasvir/grazoprevir 81.6% (n = 38), and glecaprevir/pibrentasvir 84.6% (n = 13). NS5A RASs were present in 71.0% (n = 210) of patients who achieved SVR and in 66.7% (n = 30) of patients who subsequently relapsed. NS3 RASs were detected in 20 patients (20%) in the SVR group and 1 patient in the relapse group. NS5B RASs were observed in only 3 patients. Cirrhosis was a predictor of relapse after retreatment, as was previous treatment with sofosbuvir/velpatasvir. Conclusions: In our cohort, the SVR rate for sofosbuvir/velpatasvir/voxilaprevir was higher than with other salvage regimens. The presence of NS5A, NS5B, or NS3 RASs did not appear to negatively influence retreatment outcomes.

Inhibition of MERTK reduces organ fibrosis in mouse models of fibrotic disease.

Transforming growth factor-ß (TGFß) drives fibrosis and disease progression in a number of chronic disorders, but targeting this ubiquitously expressed cytokine may not yield a viable and safe antifibrotic therapy. Here, we sought to identify alternative ways to inhibit TGFß signaling using human hepatic stellate cells and macrophages from humans and mice in vitro, as well as mouse models of liver, kidney, and lung fibrosis. We identified Mer tyrosine kinase (MERTK) as a TGFß-inducible effector of fibrosis that was up-regulated during fibrosis in multiple organs in three mouse models. We confirmed these findings in liver biopsy samples from patients with metabolic dysfunction-associated fatty liver disease (MAFLD). MERTK also induced TGFß expression and drove TGFß signaling resulting in a positive feedback loop that promoted fibrosis in cultured cells. MERTK regulated both canonical and noncanonical TGFß signaling in both mouse and human cells in vitro. MERTK increased transcription of genes regulating fibrosis by modulating chromatin accessibility and RNA polymerase II activity. In each of the three mouse models, disrupting the fibrosis-promoting signaling loop by reducing MERTK expression reduced organ fibrosis. Pharmacological inhibition of MERTK reduced fibrosis in these mouse models either when initiated immediately after injury or when initiated after fibrosis was established. Together, these data suggest that MERTK plays a role in modulating organ fibrosis and may be a potential target for treating fibrotic diseases.

A Cell Specific Effect of MBOAT7 MAFLD-risk Variant on Immune Cells.

BACKGROUND: Disease risk variants are likely to affect gene expression in a context- and cell-type specific manner. The membrane bound O-acyltransferase domain containing 7 (MBOAT7) rs8736 metabolic-dysfunction-associated fatty liver disease (MAFLD)-risk variant was recently reported to be a negative regulator of toll-like receptors (TLRs) signalling in macrophages. Whether this effect is generic or cell-type specific in immune cells is unknown. METHODS: We investigated the impact of modulating TLR signaling on MBOAT7 expression in peripheral blood mononuclear cells (PBMCs). We also examined whether the rs8736 polymorphism in MBOAT7 regulates this effect. Furthermore, we measured the allele-specific expression of MBOAT7 in various immune cell populations under both unstimulated and stimulated conditions. RESULTS: We show that MBOAT7 is down-regulated by TLRs in PBMCs. This effect is modulated by the MBOAT7 rs8736 polymorphism. Additionally, we provide evidence that MBOAT7 acts primarily as a modulator of TLR signalling in mononuclear phagocytes. CONCLUSION: Our results highlight the importance of studying Genome-Wide Association Studies (GWAS) signals in the specific cell types in which alterations of gene expression are found.

Hepatitis B virus and hepatitis C virus affect mitochondrial function through different metabolic pathways, explaining virus-specific clinical features of chronic hepatitis.

BACKGROUND: Hepatitis C virus (HCV) and hepatitis B virus (HBV) cause chronic hepatitis with important clinical differences. HCV causes hepatic steatosis and insulin resistance, while HBV confers increased risk of liver cancer. We hypothesised these differences may be due to virus-specific effects on mitochondrial function. METHODS: Seahorse technology was utilised to investigate effects of virus infection on mitochondrial function. Cell based assays were used to measure mitochondrial membrane potential and quantify pyruvate and lactate. Mass spectrometry was performed on mitochondria isolated from HBV expressing, HCV infected and control cells cultured with isotope-labelled amino acids, to identify proteins with different abundance. Altered expression of key mitochondrial proteins was confirmed by real time PCR and western blot. RESULTS: Reduced mitochondrial function and ATP production were observed with HCV infection and HBV expression. HCV impairs glycolysis and reduces expression of genes regulating fatty acid oxidation, promoting lipid accumulation. HBV causes lactate accumulation by increasing expression of lactate dehydrogenase A, which converts pyruvate to lactate. In HBV expressing cells there was marked enrichment of pyruvate dehydrogenase kinase, inhibiting conversion of pyruvate to acetyl-CoA and thereby reducing its availability for mitochondrial oxidative phosphorylation. CONCLUSIONS: HCV and HBV impair mitochondrial function and reduce ATP production. HCV reduces acetyl-CoA availability for energy production by impairing fatty acid oxidation, causing lipid accumulation and hepatic steatosis. HBV has no effect on fatty oxidation but reduces acetyl-CoA availability by disrupting pyruvate metabolism. This promotes lactic acidosis and oxidative stress, increasing the risk of disease progression and liver cancer.

Serum PRO-C3 is useful for risk prediction and fibrosis assessment in MAFLD with chronic kidney disease in an Asian cohort.

BACKGROUND: Metabolic dysfunction-associated fatty liver disease (MAFLD) is an emerging risk factor for chronic kidney disease (CKD). N-terminal propeptide of collagen type 3 (PRO-C3) is a biomarker of advanced fibrosis in MAFLD and PRO-C3 may be involved in renal fibrosis. We aimed to use PRO-C3 measurements to generate a new algorithmic score to test the prediction of MAFLD with chronic kidney disease (MAFLD-CKD). METHODS: A derivation and independent validation cohort of 750 and 129 Asian patients with biopsy-confirmed MAFLD were included. Serum PRO-C3 concentration was measured and regression analyses were performed to examine associations with MAFLD-CKD. A derivative algorithm for MAFLD-CKD risk prediction was evaluated with receiver operator characteristic (ROC) curve analysis. RESULTS: The study included two Asian cohorts (n = 180 with MAFLD-CKD; mean-eGFR: 94.93 mL/min/1.73 m2; median-urinary albumin-to-creatinine ratio: 6.58 mg/mmol). PRO-C3 was associated with the severity of MAFLD-CKD and independently associated with MAFLD-CKD (adjusted odds ratio = 1.16, 95% confidence interval [CI]: 1.08-1.23, p < .001). A new non-invasive score (termed PERIOD) including PRO-C3 efficiently predicted MAFLD-CKD (AUROC = .842, 95% CI: .805-.875). Accuracy, specificity and negative predictive values were 80.2%, 85.1% and 88.4%, respectively. In the validation cohort, the PERIOD score had good diagnostic performance (AUROC = .807, 95% CI: .691-.893) with similar results in all patient subgroups. In the MAFLD-CKD subgroup, the accuracy for identifying advanced fibrosis was further improved by combining the PRO-C3-based ADAPT with the Agile 3+ scores (AUROC = .90, 95% CI: .836-.964). CONCLUSIONS: The PERIOD score is helpful for accurately predicting the risk of MAFLD-CKD. PRO-C3 can also be used to assess liver fibrosis in people with MAFLD-CKD.

Heterogeneity of hepatocellular carcinoma: from mechanisms to clinical implications.

Hepatocellular Carcinoma (HCC) is one of the most common types of primary liver cancer. Current treatment options have limited efficacy against this malignancy, primarily owing to difficulties in early detection and the inherent resistance to existing drugs. Tumor heterogeneity is a pivotal factor contributing significantly to treatment resistance and recurrent manifestations of HCC. Intratumoral heterogeneity is an important aspect of the spectrum of complex tumor heterogeneity and contributes to late diagnosis and treatment failure. Therefore, it is crucial to thoroughly understand the molecular mechanisms of how tumor heterogeneity develops. This review aims to summarize the possible molecular dimensions of tumor heterogeneity with an emphasis on intratumoral heterogeneity, evaluate its profound impact on the diagnosis and therapeutic strategies for HCC, and explore the suitability of appropriate pre-clinical models that can be used to best study tumor heterogeneity; thus, opening new avenues for cancer treatment.

Corrigendum to "Trends in decompensated cirrhosis and hepatocellular carcinoma among people with a hepatitis B notification in New South Wales" [JHEP Reports 4 (2022)].

[This corrects the article DOI: 10.1016/j.jhepr.2022.100552.].

Using a human colonoid-derived monolayer to study bacteriophage translocation.

Bacteriophages (phages) are estimated to be the most abundant microorganisms on Earth. Their presence in human blood suggests that they can translocate from non-sterile sites such as the gastrointestinal tract where they are concentrated. To examine phage translocation ex vivo, we adapted a primary colonoid monolayer model possessing cell diversity and architecture, and a thick layer of mucus akin to the colonic environment in vivo. We show that the colonoid monolayer is superior to the Caco-2 cell-line model, possessing intact and organized tight junctions and generating a physiologically relevant mucus layer. We showed, using two different phages, that translocation across the colonoid monolayer was largely absent in differentiated monolayers that express mucus, unlike Caco-2 cultures that expressed little to no mucus. By stimulating mucus production or removing mucus, we further demonstrated the importance of colonic mucus in preventing phage translocation. Finally, we used etiological drivers of gut permeability (alcohol, fat, and inflammatory cytokines) to measure their effects on phage translocation, demonstrating that all three stimuli have the capacity to amplify phage translocation. These findings suggest that phage translocation does occur in vivo but may be largely dependent on colonic mucus, an important insight to consider in future phage applications.

Attitudes towards transjugular intrahepatic portosystemic shunt (TIPS) in Australia: a national survey of TIPS centres.

BACKGROUND: Transjugular intrahepatic portosystemic shunt (TIPS) is a minimally invasive therapeutic option to treat the sequelae of portal hypertension. It is unclear whether current international recommendations are reflected in current clinical practice across Australia and the extent of variations in care. This study aimed to address this gap in knowledge and benchmark the current landscape of TIPS services in Australia against international guidelines. METHODS: We designed a 42-item questionnaire according to practice-based recommendations and standards of international guidelines to investigate current landscape of TIPS service across four key domains: (1) service provision, (2) patient selection and indications, (3) best procedure practice, and (4) postoperative care. RESULTS: Gastroenterologist/hepatologists from 23 major liver centres (67.6%) across Australia currently performing TIPS completed the questionnaire. Between 2017 and 2020, there were 456 elective TIPS insertions. Units offering TIPS service had a low median number of TIPS insertions (n=7 per annum). More than half of respondents (56.5%) did not have institutional clinical practice protocols. There was marked variation in practices across institutions in terms of TIPS indications and patient selection. Despite variations, the success rate of elective TIPS was high at 91.7% (79-100%), with 86.6% (29-100%) for rescue TIPS. There was significant variation in postoperative follow-up and care. CONCLUSION: Current TIPS practice in Australia varies significantly across institutions. There is a need for a national consensus clinical practice guidelines to improve access and minimise unwarranted variation. A national registry for TIPS could measure, monitor, and report on quality of clinical care and patient outcomes.

Geographic disparities in access to liver transplant for advanced cirrhosis: Time to ring the alarm!

Decompensated cirrhosis and hepatocellular cancer are major risk factors for mortality worldwide. Liver transplantation (LT), both live-donor LT or deceased-donor LT, are lifesaving, but there are several barriers toward equitable access. These barriers are exacerbated in the setting of critical illness or acute-on-chronic liver failure. Rates of LT vary widely worldwide but are lowest in lower-income countries owing to lack of resources, infrastructure, late disease presentation, and limited donor awareness. A recent experience by the Chronic Liver Disease Evolution and Registry for Events and Decompensation consortium defined these barriers toward LT as critical in determining overall survival in hospitalized cirrhosis patients. A major focus should be on appropriate, affordable, and early cirrhosis and hepatocellular cancer care to prevent the need for LT. Live-donor LT is predominant across Asian countries, whereas deceased-donor LT is more common in Western countries; both approaches have unique challenges that add to the access disparities. There are many challenges toward equitable access but uniform definitions of acute-on-chronic liver failure, improving transplant expertise, enhancing availability of resources and encouraging knowledge between centers, and preventing disease progression are critical to reduce LT disparities.

Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation.

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.

Inhibition of cellular factor TM6SF2 suppresses secretion pathways of Hepatitis B, Hepatitis C and Hepatitis D viruses.

Chronic viral hepatitis is caused by hepatitis B virus, hepatitis C virus or hepatitis D virus (HBV, HCV, and HDV). Despite different replication strategies, all these viruses rely on secretion through the host endoplasmic reticulum-Golgi pathway, providing potential host targets for antiviral therapy. Knockdown of transmembrane 6 superfamily member 2 (TM6SF2) in virus cell culture models reduced secretion of infectious HCV virions, HDV virions and HBV subviral particles. Moreover, in a cohort of people with hepatitis B a TM6SF2 polymorphism (rs58542926 CT/TT, which causes protein misfolding and reduced TM6SF2 in the liver) correlated with lower concentrations of subviral particles in blood, complementing our previous work showing decreased HCV viral load in people with this polymorphism. In conclusion, the host protein TM6SF2 plays a key role in secretion of HBV, HCV and HDV, providing the potential for novel pan-viral agents to treat people with chronic viral hepatitis.