Mechanisms Underlying Hepatitis C Virus-Associated Hepatic Fibrosis

Inhibitory effects of Curcumae Radix carbonisata-based carbon dots against liver fibrosis induced by carbon tetrachloride in mice

As a processed product of traditional Chinese medicine Curcumae Radix, Curcumae Radix Carbonisata (CRC) has been widely used in the treatment of liver diseases in ancient medical books. In this study, novel carbon dots (CDs) extending from 1.0 to 4.5 nm were separated from fluid extricates of CRC. Meanwhile, a liver fibrosis model induced by carbon tetrachloride (CCl4) was utilized to determine the inhibitory effects of CRC-CDs against liver fibrosis. The results exhibited the CRC-CDs with a quantum yield of 1.34% have a significant inhibitory effect on CCl4-induced liver fibrosis, as demonstrated by improving hepatocyte degeneration and necrosis, inflammatory cell infiltration and fibrotic tissue hyperplasia, downregulating the levels of alanine transaminase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), direct bilirubin (DBIL), total bile acid (TBA), triglyceride (TG), tumour necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1β in the serum, upregulating the contents of superoxide dismutase (SOD), reduced glutathione (GSH), and downregulating the concentration of malondialdehyde (MDA), which lays an important foundation for the development of CRC-CDs as a novel drug for the treatment of liver fibrosis, and provide a certain experimental basis for the clinical application of CRC-CDs in the future.

HCV- and HBV-mediated liver cancer converge on similar transcriptomic landscapes and immune profiles

Hepatocellular carcinoma (HCC) remains a leading cause of cancer-related deaths worldwide, and a large proportion is attributable to viral causes, including hepatitis B (HBV) and C viruses (HCV). The pathogenesis of viral-mediated HCC can differ between HBV and HCV, but it is unclear how much these differences influence the tumors' final molecular and immune profiles. Additionally, there are known sex differences in the molecular etiology of HCC, but sex differences have not been explored in the context of viral-mediated HCC. To determine the extent to which the viral status and sex impact the molecular and immune profiles of HCC, we performed differential expression and immune cell deconvolution analyses. We identified a large number of differentially expressed genes unique to the HBV or HCV tumor:tumor-adjacent comparison. Pathway enrichment analyses demonstrated that changes unique to the HCV tumor:tumor-adjacent tissue were dominated by changes in immune pathways. Immune cell deconvolution demonstrated that HCV tumor-adjacent tissue had the largest immune cell infiltrate, with no difference in the immune profiles within HBV and HCV tumor samples. Overall, this work demonstrates the convergence of HBV- and HCV-mediated HCC on a similar transcriptomic landscape and immune profile despite differences in the surrounding tissue.

Review of the Effects of Antiviral Therapy on Hepatitis B/C-Related Mortality and the Regression of Fibrosis

Hepatitis B and Hepatitis C are viral causes of Hepatitis that lead to significant worldwide mortality and morbidity through the sequelae of fibrosis and hepatocellular carcinoma. In this review, we have summarized recent studies that have examined the effects of antiviral therapy on the regression of fibrosis and the reduction in mortalities associated with the viruses. Antiviral therapy significantly decreases mortality and induces the regression of fibrosis.

The HCV-Melanoma Paradox: First Multi-Cohort and Molecular Net-Work Analysis Reveals Lower Incidence but Worse Outcomes-Integrating Clinical, Real-World, and In Silico Data

Background and Objectives: The relationship between hepatitis C virus (HCV) infection and melanoma remains poorly understood. This study aimed to investigate the association between HCV and melanoma, assess outcomes in patients with both conditions, and explore potential molecular mechanisms connecting the two diseases. Materials and Methods: We conducted a retrospective cohort study of 142 melanoma patients, including 29 with HCV-related cirrhosis, and analyzed their clinical outcomes. For external validation, we used the TriNetX Global Collaborative Network database, comprising 219,960 propensity-matched patients per group. An in silico analysis was performed to identify the molecular pathways linking HCV and melanoma. Results: In the retrospective cohort, HCV-positive melanoma patients showed an increased risk of early relapse (41.4% vs. 18.6%, p = 0.014), recurrence (65.5% vs. 39.8%, p = 0.020), and mortality (65.5% vs. 23.0%, p < 0.001) compared to HCV-negative patients. TriNetX data analysis revealed that HCV-positive patients had a 53% lower risk of developing melanoma (RR = 0.470, 95% CI: 0.443-0.498, p < 0.001). However, HCV-positive melanoma patients had higher all-cause mortality (HR = 1.360, 95% CI: 1.189-1.556, p < 0.001). An in silico analysis identified key molecular players, including IL-6 and CTLA4, in the HCV-melanoma network. Conclusions: While HCV infection may be associated with a lower risk of melanoma development, HCV-positive patients who develop melanoma have poorer outcomes. The identified molecular pathways provide potential targets for future research and therapeutic interventions.

HCV- and HBV-mediated liver cancer converge on similar transcriptomic landscapes and immune profiles

Hepatocellular carcinoma (HCC) remains a leading cause of cancer-related deaths worldwide, and a large proportion of HCC is attributable to viral causes including hepatitis B (HBV) and C virus (HCV). The pathogenesis of viral-mediated HCC can differ between HBV and HCV, but it is unclear how much these differences influence the tumors' final molecular and immune profiles. Additionally, there are known sex differences in the molecular etiology of HCC, but sex differences have not been explored in the context of viral-mediated HCC. To determine the extent to which the viral status and sex impact the molecular and immune profiles of HCC, we performed differential expression and immune cell deconvolution analyses. We identified a large number of differentially expressed genes unique to the HBV or HCV tumor:tumor-adjacent comparison. Pathway enrichment analyses demonstrated that the changes unique to the HCV tumor:tumor-adjacent tissue were predominated by changes in the immune pathways. Immune cell deconvolution demonstrated that HCV tumor-adjacent tissue had the largest immune cell infiltrate, with no difference in the immune profiles within HBV and HCV tumor samples. We subsequently segregated the differential expression analyses by sex, but demonstrated that the low number of female samples led to an overestimate of differentially expressed genes unique to male tumors. This limitation highlights the importance of additional sampling of female HCC tumors to allow for a more complete analysis of the sex differences in HCC. Overall, this work demonstrates the convergence of HBV- and HCV-mediated HCC on a similar transcriptomic landscape and immune profile despite differences in the surrounding tissue.

Assessment of Short-Term Effects of Cell Transplantation in Cirrhosis DUE to HCV

BACKGROUND AND OBJECTIVES

Recent studies have highlighted the potential of fetal hepatic stem cells in regenerative treatments for liver diseases. This study aimed to evaluate the short-term effects of fetal stem cell transplantation in patients with liver cirrhosis resulting from chronic hepatitis C.

MATERIALS AND METHODS

Thirty patients with liver cirrhosis of all Child-Turcotte-Pugh classes due to chronic hepatitis C, aged 18 to 65 years, were selected for this study. A single intravenous dose of 1 ml containing 6*106 fetal hepatic stem cells, diluted in 20.0 ml of 0.9% sodium chloride solution, was administered. The efficacy of the treatment was assessed by measuring levels of ALT, AST, total and direct bilirubin, gamma-glutamyltranspeptidase, alkaline phosphatase, total protein, and albumin before and after cell therapy.

RESULTS

Post-treatment, a significant reduction was noted in the Child-Pugh score from 8 [6-9] to 7 [6-8] (p<0.001) and the MELD index from 11 [7-15] to 10 [7-14] (p=0.004). Skin itching decreased from 36.7% to 10%. Complaints of weakness increased significantly from 3.3% to 23.3% after 30 days of therapy (p=0.014), and the incidence of reduced appetite increased from 20% to 46.7% (p=0.021). No statistical differences were observed in the frequency of nosebleeds (86.7% initially vs. 90% at day 30, p=0.655) or drowsiness (63.3% initially vs. 76.7% at day 30, p=0.157). Significant reductions were noted in ALT levels by 35% and total bilirubin by 44%. The lack of significant changes in indicators of hepatic-cell insufficiency, particularly the protein-forming function as reflected in total protein and albumin levels, is likely due to the extent of liver tissue damage and thus a delayed recovery.

CONCLUSION

The findings of this study affirm the clinical efficacy and promise of fetal hepatic stem cell therapy as part of a comprehensive treatment regimen for patients with liver cirrhosis.

Microbiota and Gut-Liver Axis: An Unbreakable Bond?

The gut microbiota, amounting to approximately 100 trillion (1014) microbes represents a genetic repertoire that is bigger than the human genome itself. Evidence on bidirectional interplay between human and microbial genes is mounting. Microbiota probably play vital roles in diverse aspects of normal human metabolism, such as digestion, immune modulation, and gut endocrine function, as well as in the genesis and progression of many human diseases. Indeed, the gut microbiota has been most closely linked to various chronic ailments affecting the liver, although concrete scientific data are sparse. In this narrative review, we initially discuss the basic epidemiology of gut microbiota and the factors influencing their initial formation in the gut. Subsequently, we delve into the gut-liver axis and the evidence regarding the link between gut microbiota and the genesis or progression of various liver diseases. Finally, we summarise the recent research on plausible ways to modulate the gut microbiota to alter the natural history of liver disease.

HepG2.2.15-derived exosomes facilitate the activation and fibrosis of hepatic stellate cells

BACKGROUND

The role of exosomes derived from HepG2.2.15 cells, which express hepatitis B virus (HBV)-related proteins, in triggering the activation of LX2 liver stellate cells and promoting liver fibrosis and cell proliferation remains elusive. The focus was on comprehending the relationship and influence of differentially expressed microRNAs (DE-miRNAs) within these exosomes.

AIM

To elucidate the effect of exosomes derived from HepG2.2.15 cells on the activation of hepatic stellate cell (HSC) LX2 and the progression of liver fibrosis.

METHODS

Exosomes from HepG2.2.15 cells, which express HBV-related proteins, were isolated from parental HepG2 and WRL68 cells. Western blotting was used to confirm the presence of the exosomal marker protein CD9. The activation of HSCs was assessed using oil red staining, whereas DiI staining facilitated the observation of exosomal uptake by LX2 cells. Additionally, we evaluated LX2 cell proliferation and fibrosis marker expression using 5-ethynyl-2'-deoxyuracil staining and western blotting, respectively. DE-miRNAs were analyzed using DESeq2. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were used to annotate the target genes of DE-miRNAs.

RESULTS

Exosomes from HepG2.2.15 cells were found to induced activation and enhanced proliferation and fibrosis in LX2 cells. A total of 27 miRNAs were differentially expressed in exosomes from HepG2.2.15 cells. GO analysis indicated that these DE-miRNA target genes were associated with cell differentiation, intracellular signal transduction, negative regulation of apoptosis, extracellular exosomes, and RNA binding. KEGG pathway analysis highlighted ubiquitin-mediated proteolysis, the MAPK signaling pathway, viral carcinogenesis, and the toll-like receptor signaling pathway, among others, as enriched in these targets.

CONCLUSION

These findings suggest that exosomes from HepG2.2.15 cells play a substantial role in the activation, proliferation, and fibrosis of LX2 cells and that DE-miRNAs within these exosomes contribute to the underlying mechanisms.

Contemporary Insights into Hepatitis C Virus: A Comprehensive Review

Hepatitis C virus (HCV) remains a significant global health challenge. Approximately 50 million people were living with chronic hepatitis C based on the World Health Organization as of 2024, contributing extensively to global morbidity and mortality. The advent and approval of several direct-acting antiviral (DAA) regimens significantly improved HCV treatment, offering potentially high rates of cure for chronic hepatitis C. However, the promising aim of eventual HCV eradication remains challenging. Key challenges include the variability in DAA access across different regions, slightly variable response rates to DAAs across diverse patient populations and HCV genotypes/subtypes, and the emergence of resistance-associated substitutions (RASs), potentially conferring resistance to DAAs. Therefore, periodic reassessment of current HCV knowledge is needed. An up-to-date review on HCV is also necessitated based on the observed shifts in HCV epidemiological trends, continuous development and approval of therapeutic strategies, and changes in public health policies. Thus, the current comprehensive review aimed to integrate the latest knowledge on the epidemiology, pathophysiology, diagnostic approaches, treatment options and preventive strategies for HCV, with a particular focus on the current challenges associated with RASs and ongoing efforts in vaccine development. This review sought to provide healthcare professionals, researchers, and policymakers with the necessary insights to address the HCV burden more effectively. We aimed to highlight the progress made in managing and preventing HCV infection and to highlight the persistent barriers challenging the prevention of HCV infection. The overarching goal was to align with global health objectives towards reducing the burden of chronic hepatitis, aiming for its eventual elimination as a public health threat by 2030.

Antiviral treatment significantly reduces the levels of CXCL9, CXCL10 and CXCL11 in chronic hepatitis C

In this study, we aimed to elucidate the changes in the immune response during antiviral treatment of patients with chronic hepatitis C, with an emphasis on the chemokine dynamics and their association with liver fibrosis. Serum concentrations of 12 chemokines. (CCL2, CCL3, CCL4, CCL11, CCL17, CCL20, CXCL1, CXCL5, CXCL8, CXCL9, CXCL10 and CXCL11) were measured in 32 patients with chronic hepatitis C before direct-acting antiviral treatment and after sustained virological response using bead-based flow cytometry. Chemokine levels were also measured in 14 sex- and age-matched healthy individuals. Concentrations of CXCL9, CXCL10, CXCL11 and CCL20 were significantly higher in chronic hepatitis C patients before direct-acting antiviral treatment compared to healthy individuals. We also observed a significant reduction in CXCL9, CXCL10 and CXCL11 levels after sustained virological response. Furthermore, we demonstrated a strong positive correlation between CXCL9, CXCL10 and CXCL11 levels before antiviral treatment. When considering liver fibrosis, we found significantly higher levels of CXCL10 and lower levels of CCL17 and CXCL5 in pre-treatment patients with severe fibrosis. None of the analysed chemokines were able to predict METAVIR fibrosis score reduction after sustained virological response. The results of this study emphasize the importance of proinflammatory pathways in liver fibrosis immunopathology during chronic hepatitis C. Finally, our results also characterized CXCL10 as the chemokine which most accurately distinguished pre-treatment CHC patients and healthy individuals.

IFN-γ, IL-17, IL-22+ CD4+ subset in patients with hepatitis C virus and correlation with clinical factor

BACKGROUND

CD4+ T cell responses in HCV infection have a crucial role in the immunopathology of hepatitis C virus (HCV) infection. Our aim was to investigate the frequency of Th1, Th17, and Th22 cells in HCV-infected patients and elucidate their role in the progression of the disease.

METHODS

Twenty-six HCV-infected patients and 26 healthy individuals were recruited. Peripheral blood mononuclear cells (PBMCs) were stained to separate CD4, IFN-γ, IL-17, and IL-22 producing cells using flow cytometry.

RESULTS

Results showed that the mean expression of IL-22 in CD4+ T cells was significantly lower in HCV-infected patients compared to healthy controls. About correlation with clinical factor and T subsets, a negative correlation between the frequency of CD4+ IFN-γ+ cells and Thyroxine level (T4) was observed in the patients. The data showed a positive link between thyroid-stimulating hormone (TSH), cholesterol levels, and the frequency of Th17 cells. In addition, a positive correlation was seen between serum creatinine level with both Th1 and Th17. Ultimately, it was found that there was a positive link between viral burden and IL-17+ IL-22+ cells and a negative correlation between viral load and pure Th22.

CONCLUSIONS

Our findings indicate that Th22 cells may play a part in the immunopathology of HCV and show the associations between Thelper subsets and the clinical signs of the disease.

Yohimbine ameliorates liver inflammation and fibrosis by regulating oxidative stress and Wnt/β-catenin pathway

BACKGROUND AND PURPOSE

Chronic liver injury, caused by various aetiologies, causes recurrent tissue damage, culminating in decreased liver regenerative ability and resulting in fibrosis followed by cirrhosis. In this study, the anti-fibrotic activity of Yohimbine hydrochloride (YHC) was investigated using various in vitro models and in vivo models.

METHODS

To assess the anti-inflammatory, antioxidant, and anti-fibrotic effects of YHC, lipopolysaccharide or TGF-β induced differentiation or lipid-induced oxidative-stress models were employed using HLECs, HSC-LX2, and HepG2 cells. Further, thioacetamide (TAA) induced hepatic inflammation/fibrosis models were utilized to validate the YHC's anti-fibrotic activity in rats.

RESULTS

Inflammation/differentiation experiments in HLECs and HSC-LX2 revealed that YHC treatment significantly (p < 0.001) mitigated the lipopolysaccharide or TGF-β induced upregulation of inflammatory and fibrotic markers expression respectively. In addition, YHC dose-dependently reduced the TGF-β induced migration and palmitic acid-induced oxidative stress in HepG2 cells. Further, TAA administration (5 weeks) in vivo rat model showed increased inflammatory marker levels/expression, oxidative stress, and pathological abnormalities. Additionally, TAA administration (9 weeks) elevated the fibrotic marker expression, collagen deposition in liver tissues, and shortened longevity in rats. Treatment with YHC dose-dependently mitigated the TAA-induced abnormalities in both inflammation and fibrosis models and improved the survival of the rats. Further mechanistic approaches revealed that TAA administration elevated the JNK, Wnt components and β-catenin expression in hepatic stellate cells and animal tissues. Further treatment with YHC significantly modulated the JNK/Wnt/β-catenin signaling. Moreover, the β-catenin nuclear translocation results showed that β-catenin levels were significantly elevated in the nuclear fraction of TAA control samples and reduced in YHC-treated samples.

CONCLUSION

Yohimbine treatment significantly improved inflammation and fibrosis by inhibiting differentiation, oxidative stress, and collagen deposition by partly modulating the JNK/Wnt/β-catenin pathway. These results might serve as a foundation for proposing yohimbine as a potential lead compound for liver fibrosis.

The association between alcohol, betel nut, and cigarette use with hepatitis C virus infection in Taiwan

Hepatitis C virus (HCV) infection may cause chronic liver disease, liver cirrhosis, and liver cancer. It has been reported to associate with habits including alcohol, betel nut and cigarette use. We aimed to investigate the association between alcohol, betel nut, and cigarette use with HCV infection in Taiwan and to explore their effects. A total of 121,421 participants were enrolled from the Taiwan Biobank. They were stratified into two groups according to whether they had (n = 2750; 2.3%) or did not have (n = 118,671; 97.7%) HCV infection. All participants were also classified into four groups according to the number of habits, including a history of alcohol drinking, betel nut chewing, and cigarette smoking. There were 85,406 (no habit), 24,299 (one habit), 8659 (two habits), and 3057 (three habits) participants in the four groups, respectively. Multivariable analysis showed that the participants who had an alcohol drinking history (odds ratio [OR] 1.568; 95% confidence interval [CI] 1.388-1.773; p < 0.001), betel nut chewing history (OR 1.664; 95% CI 1.445-1.917; p < 0.001), cigarette smoking history (OR 1.387; 95% CI 1.254-1.535; p < 0.001), were significantly associated with HCV infection. Furthermore, the participants were classified into four groups according to the number of habits as follows: 85,406 (no habit), 24,299 (one habit), 8659 (two habits), and 3057 (three habits). The HCV infection rates in these four groups were 2.11%, 2.14%, 3.23%, and 4.78%, respectively. Compared to the participants with no or one habit, those with two habits had a higher HCV infection rate (all p < 0.001). In addition, compared to the participants who had no, one or two habits, those who had three habits also had higher HCV infection rates (all p < 0.001). The participants who had three habits had the highest prevalence of HCV infection. In an era when most HCV can be cured, understanding the epidemiology link between habits and HCV may help the case finding.

Hybrid model for precise hepatitis-C classification using improved random forest and SVM method

Hepatitis C Virus (HCV) is a viral infection that causes liver inflammation. Annually, approximately 3.4 million cases of HCV are reported worldwide. A diagnosis of HCV in earlier stages helps to save lives. In the HCV review, the authors used a single ML-based prediction model in the current research, which encounters several issues, i.e., poor accuracy, data imbalance, and overfitting. This research proposed a Hybrid Predictive Model (HPM) based on an improved random forest and support vector machine to overcome existing research limitations. The proposed model improves a random forest method by adding a bootstrapping approach. The existing RF method is enhanced by adding a bootstrapping process, which helps eliminate the tree's minor features iteratively to build a strong forest. It improves the performance of the HPM model. The proposed HPM model utilizes a 'Ranker method' to rank the dataset features and applies an IRF with SVM, selecting higher-ranked feature elements to build the prediction model. This research uses the online HCV dataset from UCI to measure the proposed model's performance. The dataset is highly imbalanced; to deal with this issue, we utilized the synthetic minority over-sampling technique (SMOTE). This research performs two experiments. The first experiment is based on data splitting methods, K-fold cross-validation, and training: testing-based splitting. The proposed method achieved an accuracy of 95.89% for k = 5 and 96.29% for k = 10; for the training and testing-based split, the proposed method achieved 91.24% for 80:20 and 92.39% for 70:30, which is the best compared to the existing SVM, MARS, RF, DT, and BGLM methods. In experiment 2, the analysis is performed using feature selection (with SMOTE and without SMOTE). The proposed method achieves an accuracy of 41.541% without SMOTE and 96.82% with SMOTE-based feature selection, which is better than existing ML methods. The experimental results prove the importance of feature selection to achieve higher accuracy in HCV research.

mmu-miRNA-342-3p promotes hepatic stellate cell activation and hepatic fibrosis induced by Echinococcus multilocularis infection via targeting Zbtb7a

Liver fibrosis is one of the histopathological characters during Echinococcus multilocularis infection. The activation of hepatic stellate cells (HSCs) is a key event in the development of liver fibrosis. However, the molecular mechanism of HSC activation in the E. multilocularis infection-induced liver fibrosis remains largely unclear. Here, we reported that mmu-miR-342-3p was most dominantly expressed in HSCs and was upregulated in the HSCs in response to E. multilocularis infection. We further showed that mmu-miR-342-3p was able to bind to the 3' UTR of the Zbtb7a gene and regulated its expression. Moreover, mmu-miR-342-3p expression was negatively correlated with its target gene Zbtb7a in HSCs during E. multilocularis infection. Knockdown of mmu-miR-342-3p promoted the expression of Gfap in the activated HSCs in vitro. In the E. multilocularis-infected mice, knockdown of mmu-miR-342-3p suppressed the expression of α-Sma, Col1α1, and TGF-β but promoted the expression of Gfap. Therefore, mmu-miR-342-3p is a key regulator for activation of HSCs, and inhibiting mmu-miR-342-3p to promote Zbtb7a-mediated TGF-β signaling in activated HSCs could be a novel strategy to treat liver fibrosis induced by E. multilocularis.

The Influence of Single Nucleotide Polymorphisms on Vitamin D Receptor Protein Levels and Function in Chronic Liver Disease

Single nucleotide polymorphisms (SNPs) in the vitamin D receptor (VDR) gene have been associated with chronic liver disease. We investigated the role of VDR SNPs on VDR protein levels and function in patients with chronic liver disease. VDR expression levels were determined in peripheral T lymphocytes (CD3+VDR+), monocytes (CD14+VDR+), and plasma from patients (n = 66) and healthy controls (n = 38). Genotyping of SNPs and the determination of expression of VDR/vitamin D-related genes were performed by using qPCR. The effect of FokI SNP on vitamin D-binding to VDR was investigated by molecular dynamics simulations. CD14+VDR+ cells were correlated with the MELD score. The ApaI SNP was associated with decreased CD3+VDR+ levels in cirrhotic patients and with higher liver stiffness in HCV patients. The BsmI and TaqI SNPs were associated with increased VDR plasma concentrations in cirrhotic patients and decreased CD14+VDR+ levels in HCV patients. The FokI SNP was associated with increased CD3+VDR+ levels in cirrhotic patients and controls. VDR polymorphisms were significantly related to the expression of genes critical for normal hepatocyte function and immune homeostasis. VDR expression levels were related to the clinical severity of liver disease. VDR SNPs may be related to the progression of chronic liver disease by affecting VDR expression levels.

[Exosomes in the life cycle of viruses and the pathogenesis of viral infections]

Exosomes are extracellular vesicles of endosomal origin, with a bilayer membrane, 30160 nm in diameter. Exosomes are released from cells of different origins and are detected in various body fluids. They contain nucleic acids, proteins, lipids, metabolites and can transfer the contents to recipient cells. Exosome biogenesis involves cellular proteins of the Rab GTPase family and the ESCRT system, which regulate budding, vesicle transport, molecule sorting, membrane fusion, formation of multivesicular bodies and exosome secretion. Exosomes are released from cells infected with viruses and may contain viral DNA and RNA, as well as mRNA, microRNA, other types of RNA, proteins and virions. Exosomes are capable of transferring viral components into uninfected cells of various organs and tissues. This review analyzes the impact of exosomes on the life cycle of widespread viruses that cause serious human diseases: human immunodeficiency virus (HIV-1), hepatitis B virus, hepatitis C virus, SARS-CoV-2. Viruses are able to enter cells by endocytosis, use molecular and cellular pathways involving Rab and ESCRT proteins to release exosomes and spread viral infections. It has been shown that exosomes can have multidirectional effects on the pathogenesis of viral infections, suppressing or enhancing the course of diseases. Exosomes can potentially be used in noninvasive diagnostics as biomarkers of the stage of infection, and exosomes loaded with biomolecules and drugs - as therapeutic agents. Genetically modified exosomes are promising candidates for new antiviral vaccines.

Association of NK Cells with the Severity of Fibrosis in Patients with Chronic Hepatitis C

Some NK cell subpopulations may be involved in the modulation of fibrogenesis in the liver. The aim of the study was to evaluate the relationship between the number and phenotype of NK cell subsets in peripheral blood (PB) and total NK cell percentage, population density and the degree of liver fibrosis of patients infected with hepatitis C virus (HCV+). The study group consisted of 56 HCV+ patients, divided into two subgroups: patients with mild or moderate fibrosis and patients with advanced liver fibrosis or cirrhosis (F ≥ 3 in METAVIR classification). The preparations were stained with H-E and AZAN staining. NK cells were targeted with anti-CD56 antibody and identified automatically in situ using the DakoVision system. Assessment of different NK cell subsets in PB was performed with the flow cytometry technique. In the PB of HCV+ patients with advanced liver fibrosis, there was a lower proportion of CD62L+; CD62L+/CD94++; CD27+; CD127+/CD27+ and CXCR3+/CD27+ NK subsets, as compared to patients with mild/moderate liver fibrosis. The results also showed no association between total PB NK cell level and total intrahepatic NK cell population density between patients with mild/moderate fibrosis and with advanced liver fibrosis. However, positive correlations between the PB levels of CD94+ and CD62L+ NK cell subsets and the intrahepatic total NK cell percentage and population density in the liver, irrespectively to the extent of fibrosis, were observed. Additionally, positive correlation was found between the PB CXCR3+/CD94+ NK cell percentages and intrahepatic NK cell percentages in patients with advanced hepatic fibrosis. Lower blood availability of specific NK subsets in patients with chronic type C hepatitis might be a cause of progression of liver fibrosis via insufficient control over hepatic stellate cells.

Periodic Characteristics of Hepatitis Virus Infections From 2013 to 2020 and Their Association With Meteorological Factors in Guangdong, China: Surveillance Study

BACKGROUND

In the past few decades, liver disease has gradually become one of the major causes of death and illness worldwide. Hepatitis is one of the most common liver diseases in China. There have been intermittent and epidemic outbreaks of hepatitis worldwide, with a tendency toward cyclical recurrences. This periodicity poses challenges to epidemic prevention and control.

OBJECTIVE

In this study, we aimed to investigate the relationship between the periodic characteristics of the hepatitis epidemic and local meteorological elements in Guangdong, China, which is a representative province with the largest population and gross domestic product in China.

METHODS

Time series data sets from January 2013 to December 2020 for 4 notifiable infectious diseases caused by hepatitis viruses (ie, hepatitis A, B, C, and E viruses) and monthly data of meteorological elements (ie, temperature, precipitation, and humidity) were used in this study. Power spectrum analysis was conducted on time series data, and correlation and regression analyses were performed to assess the relationship between the epidemics and meteorological elements.

RESULTS

The 4 hepatitis epidemics showed clear periodic phenomena in the 8-year data set in connection with meteorological elements. Based on the correlation analysis, temperature demonstrated the strongest correlation with hepatitis A, B, and C epidemics, while humidity was most significantly associated with the hepatitis E epidemic. Regression analysis revealed a positive and significant coefficient between temperature and hepatitis A, B, and C epidemics in Guangdong, while humidity had a strong and significant association with the hepatitis E epidemic, and its relationship with temperature was relatively weak.

CONCLUSIONS

These findings provide a better understanding of the mechanisms underlying different hepatitis epidemics and their connection to meteorological factors. This understanding can help guide local governments in predicting and preparing for future epidemics based on weather patterns and potentially aid in the development of effective prevention measures and policies.

Deciphering the Relationship between SARS-CoV-2 and Cancer

Some viruses are known to be associated with the onset of specific cancers. These microorganisms, oncogenic viruses or oncoviruses, can convert normal cells into cancer cells by modulating the central metabolic pathways or hampering genomic integrity mechanisms, consequently inhibiting the apoptotic machinery and/or enhancing cell proliferation. Seven oncogenic viruses are known to promote tumorigenesis in humans: human papillomavirus (HPV), hepatitis B and C viruses (HBV, HCV), Epstein-Barr virus (EBV), human T-cell leukemia virus 1 (HTLV-1), Kaposi sarcoma-associated herpesvirus (KSHV), and Merkel cell polyomavirus (MCPyV). Recent research indicates that SARS-CoV-2 infection and COVID-19 progression may predispose recovered patients to cancer onset and accelerate cancer development. This hypothesis is based on the growing evidence regarding the ability of SARS-CoV-2 to modulate oncogenic pathways, promoting chronic low-grade inflammation and causing tissue damage. Herein, we summarize the main relationships known to date between virus infection and cancer, providing a summary of the proposed biochemical mechanisms behind the cellular transformation. Mechanistically, DNA viruses (such as HPV, HBV, EBV, and MCPyV) encode their virus oncogenes. In contrast, RNA viruses (like HCV, HTLV-1) may encode oncogenes or trigger host oncogenes through cis-/-trans activation leading to different types of cancer. As for SARS-CoV-2, its role as an oncogenic virus seems to occur through the inhibition of oncosuppressors or controlling the metabolic and autophagy pathways in the infected cells. However, these effects could be significant in particular scenarios like those linked to severe COVID-19 or long COVID. On the other hand, looking at the SARS-CoV-2─cancer relationship from an opposite perspective, oncolytic effects and anti-tumor immune response were triggered by SARS-CoV-2 infection in some cases. In summary, our work aims to recall comprehensive attention from the scientific community to elucidate the effects of SARS-CoV-2 and, more in general, β-coronavirus infection on cancer susceptibility for cancer prevention or supporting therapeutic approaches.

The nationwide trends in hospital admissions, deaths, and costs related to hepatitis C stratified by psychiatric disorders and substance use: an analysis of US hospitals between 2016 and 2019

BACKGROUND AND AIMS

Hepatitis C virus (HCV) is a prominent liver disease that often presents with mental illness. We stratify the HCV population and review its healthcare burden on the US hospital system.

METHODS

The US National Inpatient Sample was used to select admissions related to HCV between 2016 and 2019. Weights were assigned to discharges, and trend analyses were performed. Strata were formed across demographics, comorbidities, psychiatric and substance use conditions, and other variables. Outcomes of interest included hospitalization incidences, mortality rates, total costs, and mean per-hospitalization costs.

RESULTS

From 2016 to 2019, there were improvements in mortality and hospitalization incidence for HCV, as well as a decline in aggregate costs across the majority of strata. Exceptions that showed cost growth included admissions with multiple psychiatric, stimulant use, or poly-substance use disorders, and a history of homelessness. Admissions with no psychiatric comorbidities, admissions with no substance use comorbidities, and admissions with housing and without HIV comorbidity showed decreasing total costs. Along with per-capita mean costs, admissions with comorbid opioid use, bipolar, or anxiety disorder showed significant increases. No significant trends in per-capita costs were found in admissions without mental illness diagnoses.

CONCLUSIONS

Most strata demonstrated decreases in hospitalization incidences and total costs surrounding HCV; however, HCV cases with mental illness diagnoses saw expenditure growth. Cost-saving mechanisms for these subgroups are warranted.

Role and mechanism of DNA methylation and its inhibitors in hepatic fibrosis

Liver fibrosis is a repair response to injury caused by various chronic stimuli that continually act on the liver. Among them, the activation of hepatic stellate cells (HSCs) and their transformation into a myofibroblast phenotype is a key event leading to liver fibrosis, however the mechanism has not yet been elucidated. The molecular basis of HSC activation involves changes in the regulation of gene expression without changes in the genome sequence, namely, via epigenetic regulation. DNA methylation is a key focus of epigenetic research, as it affects the expression of fibrosis-related, metabolism-related, and tumor suppressor genes. Increasing studies have shown that DNA methylation is closely related to several physiological and pathological processes including HSC activation and liver fibrosis. This review aimed to discuss the mechanism of DNA methylation in the pathogenesis of liver fibrosis, explore DNA methylation inhibitors as potential therapies for liver fibrosis, and provide new insights on the prevention and clinical treatment of liver fibrosis.

Oncogenic Viruses-Encoded microRNAs and Their Role in the Progression of Cancer: Emerging Targets for Antiviral and Anticancer Therapies

Approximately 20% of all cases of human cancer are caused by viral infections. Although a great number of viruses are capable of causing a wide range of tumors in animals, only seven of these viruses have been linked to human malignancies and are presently classified as oncogenic viruses. These include the Epstein-Barr virus (EBV), human papillomavirus (HPV), hepatitis B virus (HBV), hepatitis C virus (HCV), Merkel cell polyomavirus (MCPyV), human herpesvirus 8 (HHV8), and human T-cell lymphotropic virus type 1 (HTLV-1). Some other viruses, such as the human immunodeficiency virus (HIV), are associated with highly oncogenic activities. It is possible that virally encoded microRNAs (miRNAs), which are ideal non-immunogenic tools for viruses, play a significant role in carcinogenic processes. Both virus-derived microRNAs (v-miRNAs) and host-derived microRNAs (host miRNAs) can influence the expression of various host-derived and virus-derived genes. The current literature review begins with an explanation of how viral infections might exert their oncogenic properties in human neoplasms, and then goes on to discuss the impact of diverse viral infections on the advancement of several types of malignancies via the expression of v-miRNAs. Finally, the role of new anti-oncoviral therapies that could target these neoplasms is discussed.

Extracellular volume fraction obtained by dual-energy CT depicting the etiological differences of liver fibrosis

PURPOSE

To assess etiological differences in extracellular volume fraction (ECV) and evaluate its influence on staging performance.

METHODS

A total of 166 patients with normal liver (n = 14) and chronic liver disease related to viral hepatitis (n = 71), alcohol (n = 44), and nonalcoholic steatohepatitis (NASH) (n = 37) underwent dual-energy CT (DECT) of the liver (5-min equilibrium-phase images) between January 2020 and July 2022. The iodine densities of the parenchyma and aorta were measured and ECV was calculated. Comparisons of ECV between each etiology and METAVIR fibrosis stage were statistically analyzed (p < 0.05).

RESULTS

ECV in each etiology and all patients significantly increased with higher fibrosis stage (p < 0.001) and showed a strong or moderate correlation with fibrosis stage (Spearman's ρ; all patients, 0.701; viral hepatitis, 0.638; alcoholic, 0.885; NASH, 0.791). In stages F2-F4, ECV in alcoholic liver disease was significantly larger than those for viral hepatitis and NASH (p < 0.05); however, no significant difference in stage F1 was found among the three etiologies. The cutoff values and areas under the receiver operating characteristic curve (AUC-ROCs) for discriminating fibrosis stage (≥ F1- ≥ F4) were higher for alcohol (cutoff values and AUC-ROC; 20.1% and 0.708 for ≥ F1, 23.8% and 0.990 for ≥ F2, 24.3% and 0.968 for ≥ F3, and 26.6% and 0.961 for ≥ F4, respectively) compared with those for the others.

CONCLUSION

ECV in alcoholic liver disease is higher than that in other etiologies in the advanced stages of fibrosis, and etiological differences in ECV affect the staging performance of fibrosis.

Association between Liver Stiffness and Liver-Related Events in HCV-Infected Patients after Successful Treatment with Direct-Acting Antivirals

Background and Objectives: Direct-acting antivirals (DAAs) are highly effective for the treatment of chronic hepatitis C virus (HCV) infection, but the risk of liver-related events and hepatocellular carcinoma (HCC) remains after successful therapy. We aimed to evaluate post-treatment changes in liver stiffness (LS) and identify a cut-off LS value for predicting such events in chronic HCV-infected patients receiving DAA. Materials and Methods: A total of 185 patients who had achieved sustained virologic response (SVR) after DAA therapy were included. Baseline characteristics and laboratory results were retrospectively abstracted. LS was measured by transient elastography at baseline, 12, 24, 48, and 96 weeks after SVR. FIB-4 index was assessed at baseline and 48 weeks after SVR. Development of liver-related events (hepatocellular carcinoma (HCC), portal-hypertension-related decompensation, listing for transplantation, and mortality) after SVR were identified. The association between liver fibrosis and the occurrence of liver-related events was analyzed using Cox regression analysis. Results: Significant differences in LS values were observed between baseline and 24, 48, 72, and 96 weeks after SVR. FIB-4 index at 48 weeks after SVR was significantly lower than the FIB-4 index at baseline. During the 41.6-month follow-up time, the incidence rates of all liver-related events and HCC were 2.36 and 1.17 per 100 person-years, respectively. Age, LS ≥8 kPa, and FIB-4 ≥1.35 at 48 weeks post-SVR were significantly associated with the occurrence of any liver-related events. By multivariate analysis, LS ≥8 kPa at 48 weeks post-SVR remained significantly associated with any liver-related events, with an adjusted hazard ratio (95%CI) of 5.04 (1.01-25.26), p = 0.049. Conclusions: Despite a significant reduction in LS after SVR, patients with LS ≥8 kPa at 48 weeks after SVR should be regularly monitored for liver-related complications, particularly HCC development.

Exosomes: from biology to immunotherapy in infectious diseases

Exosomes are extracellular vesicles derived from the endosomal compartment, which are released by all kinds of eukaryotic and prokaryotic organisms. These vesicles contain a variety of biomolecules that differ both in quantity and type depending on the origin and cellular state. Exosomes are internalized by recipient cells, delivering their content and thus contributing to cell-cell communication in health and disease. During infections exosomes may exert a dual role, on one hand, they can transmit pathogen-related molecules mediating further infection and damage, and on the other hand, they can protect the host by activating the immune response and reducing pathogen spread. Selective packaging of pathogenic components may mediate these effects. Recently, quantitative analysis of samples by omics technologies has allowed a deep characterization of the proteins, lipids, RNA, and metabolite cargoes of exosomes. Knowledge about the content of these vesicles may facilitate their therapeutic application. Furthermore, as exosomes have been detected in almost all biological fluids, pathogenic or host-derived components can be identified in liquid biopsies, making them suitable for diagnosis and prognosis. This review attempts to organize the recent findings on exosome composition and function during viral, bacterial, fungal, and protozoan infections, and their contribution to host defense or to pathogen spread. Moreover, we summarize the current perspectives and future directions regarding the potential application of exosomes for prophylactic and therapeutic purposes.

Exosomes in chronic liver disease

Chronic liver disease (CLD) is the major cause of mortality and morbidity, particularly in developing countries. Although there has been a significant advancement in the identification and treatment of liver diseases over time, clinical results are not satisfactory in advanced liver disease. Thus, it is crucial to develop certain technology for early detection, and curative therapies and to investigate the molecular mechanisms behind CLD's pathogenesis. The study of exosomes in CLD is a rapidly developing field. They are structurally membrane-derived nano vesicles released by various cells. In CLD, exosomes released from injured hepatic cells affect intercellular communication, creating a microenvironment conducive to the illness's development. They also carry liver cell-specific proteins and miRNAs, which can be used as diagnostic biomarkers and treatment targets for various liver diseases. End-stage liver disease can only be treated by a liver transplant, however, the low availability of compatible organs, high expenses of treatment, and surgical complications significantly lower patient survival rates. Early diagnosis and therapeutic intervention of CLD positively affect the likelihood of curative treatment and high patient survival rates. Considering the possibility that exosomes could be employed as tools for disease diagnostics and clinical intervention, The current study briefly summarizes the roles of exosomes and their cargo in diagnosing and treating liver diseases.

Hepatitis Virus and Hepatocellular Carcinoma: Recent Advances

Hepatocellular carcinoma (HCC) remains a global health challenge, causing 600,000 deaths each year. Infectious factors, including hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus (HDV), have long been considered the major risk factors for the development and progression of HCC. These pathogens induce hepatocyte transformation through a variety of mechanisms, including insertional mutations caused by viral gene integration, epigenetic changes, and the induction of long-term immune dysfunction. The discovery of these mechanisms, while advancing our understanding of the disease, also provides targets for new diagnostic and therapeutic approaches. In addition, the discovery and research of chronic HEV infection over the past decade indicate that this common hepatitis virus also seems to have the potential to induce HCC. In this review, we provide an overview of recent studies on the link between hepatitis virus and HCC, as well as new diagnostic and therapeutic approaches to HCC based on these findings. Finally, we also discuss the potential relationship between HEV and HCC. In conclusion, these associations will further optimize the diagnosis and treatment of infection-associated HCC and call for better management policies.

Vitamin D Receptor Activation Targets ROS-Mediated Crosstalk Between Autophagy and Apoptosis in Hepatocytes in Cholestasic Mice

BACKGROUND & AIMS

Observational epidemiologic studies have associated vitamin D deficiency with cholestasis. We reported previously that activation of the vitamin D/vitamin D receptor (VDR) axis in cholangiocytes mitigates cholestatic liver injury by remodeling the damaged bile duct. However, the function of VDR in hepatocytes during cholestasis remains unclear.

METHODS

Paricalcitol (VDR agonist, 200 ng/kg) was injected intraperitoneally into bile duct-ligated mice every other day for 5 days. Primary hepatocytes and HepG2 hepatoma cells were transfected with Vdr short hairpin RNA, control short hairpin RNA, Vdr plasmid, control vector, Atg5 small interfering RNA (siRNA), and control siRNA. Liver histology, cell proliferation, and autophagy were evaluated.

RESULTS

Treatment with the VDR agonist paricalcitol improved liver injury in bile duct-ligated mice by up-regulating VDR expression in hepatocytes, which in turn reduced hepatocyte apoptosis by inhibiting reactive oxygen species (ROS) generation via suppressing the Ras-related C3 botulinum toxin substrate 1/reduced nicotinamide adenine dinucleotide phosphate oxidase 1 pathway. Mechanistically, upon exposure to an ROS-inducing compound, Vdr siRNA contributed to apoptosis, whereas the Vdr overexpression caused resistance to apoptosis. Interestingly, up-regulated VDR expression also increased the generation of autophagosomes and macroautophagic/autophagic flux, which was the underlying mechanism for reduced apoptosis following VDR activation. Autophagy depletion impaired the positive effects of VDR overexpression, whereas autophagy induction was synergystic with VDR overexpression. Importantly, up-regulation of VDR promoted autophagy activation by suppressing the activation of the extracellular signal-regulated kinase (ERK)/p38 mitogen-activated protein kinase (p38MAPK) pathway. Thus, a p38MAPK inhibitor abrogated the Vdr siRNA-induced decrease in autophagy and the Vdr siRNA-induced increase in apoptosis. In contrast, a Mitogen-activated protein kinase kinase (MEK)/ERK activator prevented the enhancement of autophagy and decreased apoptosis following Vdr overexpression. Moreover, the ROS inhibitor N-acetylcystein (NAC) blocked Vdr siRNA-enhanced activation of the ERK/p38MAPK pathway.

CONCLUSIONS

VDR activation mitigated liver cholestatic injury by reducing autophagy-dependent hepatocyte apoptosis and suppressing the activation of the ROS-dependent ERK/p38MAPK pathway. Thus, VDR activation may be a potential target for the treatment of cholestatic liver disease.

Hepatocytes infected with hepatitis C virus change immunological features in the liver microenvironment

Hepatitis C virus (HCV) infection is remarkably efficient in establishing viral persistence, leading to the development of liver cirrhosis and hepatocellular carcinoma (HCC). Direct-acting antiviral agents (DAAs) are promising HCV therapies to clear the virus. However, recent reports indicate potential increased risk of HCC development among HCV patients with cirrhosis following DAA therapy. CD8+ T-cells participate in controlling HCV infection. However, in chronic hepatitis C patients, severe CD4+ and CD8+ T-cell dysfunctions have been observed. This suggests that HCV may employ mechanisms to counteract or suppress the host T-cell responses. The primary site of viral replication is within hepatocytes where infection can trigger the expression of costimulatory molecules and the secretion of immunoregulatory cytokines. Numerous studies indicate that HCV infection in hepatocytes impairs antiviral host immunity by modulating the expression of immunoregulatory molecules. Hepatocytes expressing whole HCV proteins upregulate the ligands of programmed cell death protein 1 (PD-1), programmed death-ligand 1 (PD-L1), and transforming growth factor β (TGF-β) synthesis compared to those in hepatocytes in the absence of the HCV genome. Importantly, HCV-infected hepatocytes are capable of inducing regulatory CD4+ T-cells, releasing exosomes displaying TGF-β on exosome surfaces, and generating follicular regulatory T-cells. Recent studies report that the expression profile of exosome microRNAs provides biomarkers of HCV infection and HCV-related chronic liver diseases. A better understanding of the immunoregulatory mechanisms and identification of biomarkers associated with HCV infection will provide insight into designing vaccine against HCV to bypass HCV-induced immune dysregulation and prevent development of HCV-associated chronic liver diseases.

Activation of primary hepatic stellate cells and liver fibrosis induced by targeting TGF-β1/Smad signaling in schistosomiasis in mice

BACKGROUND

In mice, liver fibrosis is the most serious pathologic change during Schistosoma japonicum (S. japonicum) infection. Schistosomiasis is mainly characterized by schistosome egg-induced granulomatous fibrosis. Hepatic stellate cells (HSCs) are mainly responsible for the net accumulation of collagens and fibrosis formation in the liver. Activated HSCs regulated by transforming growth factor-β1 (TGF-β1)/Smad signaling have emerged as the critical regulatory pathway in hepatitis virus or carbon tetrachloride-induced liver fibrosis. However, the detailed mechanism of HSC activation in schistosome-induced liver fibrosis is poorly understood.

METHODS

Schistosoma japonicum-induced murine models and a control group were generated by abdominal infection with 15 (± 1) cercariae. The purity of cultured primary HSCs was evaluated by immunocytochemistry. The histopathological changes in the livers of infected mice were estimated by hematoxylin-eosin and Masson staining. Dynamic expression of pro-fibrotic molecules and microRNAs was detected by real-time quantitative PCR (RT-qPCR). Mainly members involved in the TGF-β1/Smad signaling pathway were examined via RT-qPCR and Western blot.

RESULTS

The egg-induced granulomatous inflammation formed at 4 weeks post-infection (wpi) and developed progressively. Alpha-smooth muscle actin (α-SMA), collagen I, collagen III, TGF-β1, Smad2, Smad3, and Smad4 showed a significant increase in mitochondrial RNA (mRNA) and protein expression compared with the control group at 7 and 9 weeks post-infection (wpi), while an opposite effect on Smad7 was observed. In addition, the mRNA expression of microRNA-21 (miRNA-21) was significantly increased at 7 wpi, and the mRNA expression of miRNA-454 was decreased starting from 4 wpi.

CONCLUSION

Our present findings revealed that HSCs regulated by the TGF-β1/Smad signaling pathway play an important role in liver fibrosis in S. japonicum-infected mice, which may provide proof of concept for liver fibrosis in schistosomiasis.

Tolloid-like 1 gene variant rs17047200, pretreatment FIB-4, ALBI and PALBI scores as predictors of hepatocellular carcinoma occurrence after directly acting antivirals

Aim of the study

Identifying persons at increased risk of developing hepatocellular carcinoma (HCC) after exposure to directly acting antivirals (DAAs) is of utmost importance. Our aim was to identify the predictors of de novo HCC occurrence among cirrhotic patients after hepatitis C virus (HCV) treatment using DAAs.

Material and methods

529 cirrhotic patients who initiated treatment for HCV using DAAs were followed up for 2 years from the end of treatment for development of HCC. Pretreatment clinical and laboratory data were assessed as possible predictors for HCC occurrence. Genotyping for tolloid-like 1 gene (TLL1) variant rs17047200 was assessed in all patients who developed HCC and in the matched control group.

Results

Pretreatment bilirubin, FIB-4 and platelet-albumin-bilirubin (PALBI) scores were significantly higher among those who developed HCC than those who did not develop HCC during the 2-year follow-up period while hemoglobin level was significantly lower. ROC curve analysis revealed that at a cut-off ≥ 3.07, pretreatment FIB-4 had a sensitivity of 76.5%, and negative predictive value (NPV) of 92%. At a cut-off ≥ -2.5, pretreatment PALBI score had a sensitivity of 82.4%, and NPV of 93.2%. Regarding genotyping for TLL1 rs17047200 there were no statistically significant differences between those who developed HCC during follow-up and the matched control group.

Conclusions

TLL1 rs17047200 genotyping is not helpful in predicting HCC occurrence after DAAs. On the other hand, lower pretreatment hemoglobin level and higher pretreatment bilirubin, FIB-4 and PALBI scores are associated with higher risk of HCC development after DAAs.

Hepatitis C Core Protein Induces a Genotype-Specific Susceptibility of Hepatocytes to TNF-Induced Death In Vitro and In Vivo

Hepatitis C virus (HCV) core protein is a multifunctional protein that is involved in the proliferation, inflammation, and apoptosis mechanism of hepatocytes. HCV core protein genetic variability has been implicated in various outcomes of HCV pathology and treatment. In the present study, we aimed to analyze the role of the HCV core protein in tumor necrosis factor α (TNFα)-induced death under the viewpoint of HCV genetic variability. Immortalized hepatocytes (IHH), and not the Huh 7.5 hepatoma cell line, stably expressing HCV subtype 4a and HCV subtype 4f core proteins showed that only the HCV 4a core protein could increase sensitivity to TNFα-induced death. Development of two transgenic mice expressing the two different core proteins under the liver-specific promoter of transthyretin (TTR) allowed for the in vivo assessment of the role of the core in TNFα-induced death. Using the TNFα-dependent model of lipopolysaccharide/D-galactosamine (LPS/Dgal), we were able to recapitulate the in vitro results in IHH cells in vivo. Transgenic mice expressing the HCV 4a core protein were more susceptible to the LPS/Dgal model, while mice expressing the HCV 4f core protein had the same susceptibility as their littermate controls. Transcriptome analysis in liver biopsies from these transgenic mice gave insights into HCV core molecular pathogenesis while linking HCV core protein genetic variability to differential pathology in vivo.

Circulating thrombospondin 2 levels reflect fibrosis severity and disease activity in HCV-infected patients

Among several secreted glycoproteins belonging to the thrombospondin family, thrombospondin 2 (TSP2) is involved in various functions, including collagen/fibrin formation. Liver/serum TSP2 levels have been correlated to liver fibrosis stage and disease activity in nonalcoholic fatty liver disease. This study investigated whether serum TSP2 was associated with clinicopathological features in hepatitis C virus (HCV)-infected patients as well. A total of 350 patients with HCV who had undergone liver biopsy were retrospectively enrolled and divided into a discovery cohort (n = 270) and a validation cohort (n = 80). In the discovery cohort, serum TSP2 levels were moderately correlated with both liver fibrosis stage (r = 0.426, P < 0.0001) and activity grade (r = 0.435, P < 0.0001). The area under the receiver operating characteristic curve of TSP2 for predicting severe fibrosis (≥ F3) was 0.78 and comparable to or better than those of autotaxin (0.78), FIB-4 index (0.78), and APRI (0.76). The discovery cohort findings were closely replicated in the validation cohort. Moreover, comprehensive liver genetic analysis of HCV-infected patients confirmed that the expression of the THBS2 gene encoding TSP2 was significantly higher in severely fibrotic F4 than in F1 patients. Circulating TSP2 levels may reflect the severity of hepatic fibrosis/inflammation in HCV-infected patients.

Ectodysplasin-A mRNA in exosomes released from activated hepatic stellate cells stimulates macrophage response

INTRODUCTION

The interaction between activated hepatic stellate cells (aHSCs) and macrophages is central to liver fibrosis development. The cargo contained within aHSC exosomes (aHSC-EXOs) and how aHSC-EXOs affect macrophage function is poorly understood.

METHODS

RNA from aHSC-EXOs was separated into small (<200-basepairs) and large (≥200-basepairs) RNA species, transfected into macrophages, and macrophage IL-6 and TNFα mRNA expression and protein secretion measured. Next generation sequencing was performed on EXOs from rat quiescent and aHSCs and human aHSCs. aHSCs were transfected with siRNA against ectodysplasin-A (EDA), EXOs collected, and their effect on macrophage function analyzed. Human cirrhotic liver was analyzed for EDA mRNA expression and compared to non-tumor liver (NTL).

RESULTS

Transfection with large RNA from aHSC-EXOs stimulated macrophage IL-6 and TNFα mRNA expression and protein secretion. EDA mRNA was highly expressed in aHSCs and transfection of aHSCs with EDA-siRNA decreased aHSC-EXO EDA mRNA and blunted the effect of aHSC-EXOs on macrophage function (IL-6/TNFα expression and macrophage migration). Human cirrhotic liver exhibited high EDA mRNA compared to NTL.

CONCLUSIONS

HSC activation leads to altered EXO mRNA/miRNA profiles with aHSC-EXOs mRNAs exerting a dominant role in altering macrophage function. Ectodysplasin-A mRNA is an important component in aHSC-EXOs in regulating macrophage function.

The Role of the Microbiota Gut-Liver Axis during HCV Chronic Infection: A Schematic Overview

Hepatitis C virus (HCV) still represents one of the most important worldwide health care problems. Since 2011, direct-acting antiviral (DAA) drugs have increased the number of people who have achieved a sustained virological response (SVR). Even if the program to eradicate HCV by 2030 is still ongoing, the SARS-CoV-2 pandemic has created a delay due to the reallocation of public health resources. HCV is characterized by high genetic variability and is responsible for hepatic and extra-hepatic diseases. Depending on the HCV genotype/subtype and comorbidities of patients, tailored treatment is necessary. Recently, it has been shown that liver damage impacts gut microbiota, altering the microbial community (dysbiosis) during persistent viral replication. An increasing number of studies are trying to clarify the role of the gut-liver axis during HCV chronic infection. DAA therapy, by restoring the gut microbiota equilibrium, seems to improve liver disease progression in both naïve and treated HCV-positive patients. In this review, we aim to discuss a snapshot of selected peer-reviewed papers concerning the interplay between HCV and the gut-liver axis.

Oncogenic viruses, cancer biology, and innate immunity

Malignancies that arise as a result of viral infection account for roughly 15% of cancer cases worldwide. The innate immune system is the body's first line of defense against oncogenic viral infection and is also involved in the response against viral-driven tumors. In this review, we discuss research advances made over the last five years elucidating how the innate immune system recognizes and responds to oncogenic viruses, how these viruses have evolved to escape this immune pressure, and ways that innate immunity can inform the development of novel therapeutics against oncogenic viral infection and their associated cancers.

Simple noninvasive tests for liver fibrosis diagnosis in sub-Saharan African adults with chronic viral hepatitis B or C: A cross sectional study in Cameroon

BACKGROUND AND AIMS

This study aimed at measure the correlation between simple less expensive and noninvasive tests for liver fibrosis and Fibrotest among patients with chronic hepatitis B (HBV) or C (HCV) in resource-limited settings.

MATERIALS AND METHODS

This was a cross-sectional study conducted at the Centre Pasteur of Cameroon among adults with chronic HBV or HCV infection. The correlation between aspartate aminotransferase to platelet ratio index(APRI), the gamma-glutamyl transferase to platelet ratio (GPR), and Fibrosis-4 score (FIB-4); and Fibrotest was assessed using the Spearman rank test providing the rho (ρ) coefficient of correlation.

RESULTS

Of the 52 patients (mean age: 49 years, males: 51.9%) included, 52% were infected with HBV (n = 27). The APRI, GPR, FIB-4, and Fibrotest median scores (25th-75th percentiles) were: 0.37 (0.25-0.64), 0.34 (0.20-1.45), 1.49 (0.88-3.12), and 0.43 (0.21-0.80), respectively. The correlation with Fibrotest were: APRI (ρ = 0.678, p value < 0.0001), GPR (ρ = 0.621, p value < 0.0001) and FIB-4 (ρ = 0.772, p value < 0.0001).

CONCLUSIONS

This study found a significant correlation between APRI, GPR and FIB-4; and Fibrotest among patients with chronic HBV or HCV infection in Cameroon. FIB-4 appeared as the diagnosis method with the strongest correlation with Fibrotest.

Genetic Polymorphism in Toll-Like Receptor 3 and Interferon Regulatory Factor 3 in Hepatitis C Virus-Infected Patients: Correlation with Liver Cirrhosis

Host genetic factors could play a primary role in determining the risk for cirrhosis development in chronic hepatitis C virus (HCV)-infected patients. We designed this work to study the effect of single-nucleotide polymorphism (SNP) in Toll-like receptor 3 (TLR3) and interferon regulatory factor (IRF) on the risk of HCV-related cirrhosis. This study enrolled 139 Egyptian HCV-infected patients. They were divided into patients with cirrhotic (56) and noncirrhotic (83) liver. Genotyping of rs3775291 F459F (+1234C/T) and rs3775290 L412F (+1377C/T) in TLR3 and IRF3 rs2304204 (-925A/G) was performed by restriction fragment length polymorphism-polymerase chain reaction. Although there is no significant difference in genotype and allele distribution of +1377C/T of TLR3 gene between cirrhotic and noncirrhotic subjects, CC (odds ratio [OR] = 1.572, 95% confidence interval [CI]: 0.781-3.164); TT (OR = 1.463, 95% CI: 0.351-6.104) genotypes might be considered as risk factors for liver cirrhosis. On the contrary, the analysis revealed that only one genotype (CC) and one allele (C) were detected in +1234C/T SNP, with the total disappearance of CT/TT genotypes and T allele in all subjects. On the contrary, lower frequency has been found for the AG genotype of the IRF3 (-925A/G) gene in cirrhotic patients compared with noncirrhotic ones, indicating that AG is a protective genotype (OR = 0.509, 95% CI: 0.256-1.012). Our data stressed the association of AG genotype SNP in IRF3 (-925A/G) in protection against the worth outcome of HCV infection.

Safety and Efficacy of Direct Antiviral Agents for Hepatitis C in Patients with Malignancies Other Than Liver Cancer: A Case Series

(1) Background: direct-acting antivirals (DAA) are the current standard of care for chronic hepatitis C. Oncologic patients remain among the most difficult-to-treat subgroups of hepatitis C virus (HCV)-infected patients due to their clinical frailty and complex therapeutic protocols received. (2) Methods: we retrospectively collected and analysed clinical data of 30 consecutive patients treated with DAA, between 2015 and 2022, for chronic HCV infection in the context of oncologic disease. (3) Results: most patients were females (63.3%), median age was 67 years, HCV genotype 1 was prevalent (60%), and median HCV RNA levels were 2.2 × 106 IU/mL. The most common malignancy was breast cancer (37%), and the chief oncologic drugs co-administered with DAAs were tamoxifen, platinum derivatives, cyclophosphamide, paclitaxel, rituximab and doxorubicin. Overall, 50% of patients had chronic hepatitis. A total of 76.7% underwent a sofosbuvir-based treatment. Sustained virological response 12 weeks after the end of therapy (SVR12) was reached in all patients. After SVR12, two patients died. DAA treatment was well tolerated; no patients had to stop DAA treatment or showed any adverse event or drug-drug interaction specifically attributable to DAAs. (4) Conclusions: DAA treatment should be promptly offered to oncologic patients with chronic hepatitis C in order to achieve aminotransferase normalization and viremia control, making antineoplastic therapy feasible and safe.

Small extracellular vesicles and liver diseases: From diagnosis to therapy

Extracellular vesicles (EVs), especially small EVs (sEVs) derived from liver cells, have been the focus of much attention in the normal physiology and pathogenesis of various diseases affecting the liver. sEVs are approximately 100 nm in size, enclosed within lipid bilayers, and are very stable. The lipids, proteins, and nucleic acids, including miRNAs, contained within these vesicles are known to play important roles in intercellular communication. This mini-review summarizes the application of sEVs. First, liver diseases and the related diagnostic markers are described, and the current active status of miRNA research in diagnosis of hepatocellular carcinoma (HCC) is reported. Second, the biodistribution and pharmacokinetics of sEVs are described, and the liver is highlighted as the organ with the highest accumulation of sEVs. Third, the relationship between sEVs and the pathogenesis of liver disorders is described with emphesis on the current active status of miRNA research in HCC recurrence and survival. Finally, the possibility of future therapy using sEVs from mesenchymal stem (stromal) cells for cirrhosis and other diseases is described.

Epidemiology, risk factors, and pathogenesis associated with a superbug: A comprehensive literature review on hepatitis C virus infection

Viral hepatitis is a major public health concern. It is associated with life threatening conditions including liver cirrhosis and hepatocellular carcinoma. Hepatitis C virus infects around 71 million people annually, resultantly 700,000 deaths worldwide. Extrahepatic associated chronic hepatitis C virus accounts for one fourth of total healthcare load. This review included a total of 150 studies that revealed almost 19 million people are infected with hepatitis C virus and 240,000 new cases are being reported each year. This trend is continually rising in developing countries like Pakistan where intravenous drug abuse, street barbers, unsafe blood transfusions, use of unsterilized surgical instruments and recycled syringes plays a major role in virus transmission. Almost 123–180 million people are found to be hepatitis C virus infected or carrier that accounts for 2%–3% of world’s population. The general symptoms of hepatitis C virus infection include fatigue, jaundice, dark urine, anorexia, fever malaise, nausea and constipation varying on severity and chronicity of infection. More than 90% of hepatitis C virus infected patients are treated with direct-acting antiviral agents that prevent progression of liver disease, decreasing the elevation of hepatocellular carcinoma. Standardizing the healthcare techniques, minimizing the street practices, and screening for viral hepatitis on mass levels for early diagnosis and prompt treatment may help in decreasing the burden on already fragmented healthcare system. However, more advanced studies on larger populations focusing on mode of transmission and treatment protocols are warranted to understand and minimize the overall infection and death stigma among masses.

C-reactive protein to lymphocyte count ratio is a promising novel marker in hepatitis C infection: the clear hep-c study

OBJECTIVE:

Chronic hepatitis C (CHC) is one of the most important health problems affecting the significant rate of world population and it may lead to cirrhosis and hepatocellular carcinoma. C-reactive protein to lymphocyte count ratio (CLR) is used in estimating inflammatory burden. Therefore, this study aimed to compare CLR values between CHC patients and healthy controls and between CHC patients with and without fibrosis.

METHODS:

Patients with CHC infection who visited outpatient and inpatient internal medicine clinics of our institution between January 2021 and December 2021 were enrolled to this retrospective study. CLR of the patients with CHC and healthy controls were compared. We further compared CLR of CHC patients with and without fibrosis.

RESULTS:

Median CLR of CHC and control subjects was 2.61 (5.13%) and 0.31 (0.37%), respectively. CLR of the CHC group was significantly increased compared to the CLR of the controls (p<0.001). There was a significant positive correlation between CLR and APRI score (r=0.15, p=0.04). The sensitivity and specificity of CLR in determining CHC above 0.58% level were 84% and 82%, respectively (AUC: 0.884, p<0.001, 95%CI 0.84–0.93). In subgroup analysis, CLR was 3.97 (6.6%) for CHC patients with fibrosis and 1.7 (4.4%) for CHC subjects without fibrosis (p=0.001).

CONCLUSION:

Increased CLR in patients with CHC may be an alarming finding of liver fibrosis, as CLR is associated with both CHC and hepatic fibrosis.

An MMP-degraded and cross-linked fragment of type III collagen as a non-invasive biomarker of hepatic fibrosis resolution

BACKGROUND AND AIMS

Liver fibrosis results from a prolonged wound healing response to continued injury with excessive production of extracellular proteins. In patients with chronic liver disease, the monitoring of liver fibrosis dynamics is of high interest. Whilst markers of fibrogenesis exist, markers of hepatic fibrosis resolution remain an unmet clinical need. Thus, we sought to develop an assay quantifying a circulating proteolytic fragment of cross-linked type III collagen as a biomarker of fibrolysis, testing its utility in two clinical cohorts of liver fibrosis of distinct aetiology and regressing endotype METHODS: We used a monoclonal antibody targeting the C-telopeptide of type III collagen following C-proteinase cleavage to develop and validate a neo-epitope-specific enzyme-linked immunosorbent assay (CTX-III). A potential fibrosis resolution marker, CTX-III, was measured in two clinical cohorts of patients with obesity-associated non-alcoholic fatty liver disease undergoing bariatric surgery or hepatitis C virus infection from a clinical trial study evaluating the anti-fibrotic effect of farglitazar.

RESULTS

CTX-III was robust and specific for the targeted neo-epitope with good reproducibility in EDTA plasma. We assessed type III collagen remodelling using a panel of biomarkers, including a type III collagen formation marker (PRO-C3), degradation (C3M), and CTX-III (fibrolysis). Net fibrolysis was increased in patients with non-alcoholic fatty liver disease following bariatric surgery (p < .001). Moreover, net fibrolysis identified spontaneous fibrotic regressors from stable and progressors (p < .05 and p < .001) among hepatitis C virus infection patients.

CONCLUSION

Circulating CTX-III as a marker of fibrolysis indicates the biomarker's beneficial use in assessing hepatic fibrosis resolution.

Neuromuscular Complications of SARS-CoV-2 and Other Viral Infections

In this article we review complications to the peripheral nervous system that occur as a consequence of viral infections, with a special focus on complications of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). We discuss neuromuscular complications in three broad categories; the direct consequences of viral infection, autoimmune neuromuscular disorders provoked by viral infections, and chronic neurodegenerative conditions which have been associated with viral infections. We also include discussion of neuromuscular disorders that are treated by immunomodulatory therapies, and how this affects patient susceptibility in the current context of the coronavirus disease 2019 (COVID-19) pandemic. COVID-19 is associated with direct consequences to the peripheral nervous system via presumed direct viral injury (dysgeusia/anosmia, myalgias/rhabdomyolysis, and potentially mononeuritis multiplex) and autoimmunity (Guillain Barré syndrome and variants). It has important implications for people receiving immunomodulatory therapies who may be at greater risk of severe outcomes from COVID-19. Thus far, chronic post-COVID syndromes (a.k.a: long COVID) also include possible involvement of the neuromuscular system. Whether we may observe neuromuscular degenerative conditions in the longer term will be an important question to monitor in future studies.

What Makes Cirrhosis Irreversible?-Consideration on Structural Changes

Several studies have shown that liver fibrosis, and even cirrhosis can be reversed, disproving the old “dogma” that cirrhosis is irreversible. In addition to scaring, vascular alterations appear to be critically important in the progression of chronic liver diseases. To overcome the “tipping-point” of cirrhosis, we need to understand in depth what might make it irreversible in some cases. Morphologically, the initial, as well as the advanced stages of cirrhosis are characterized by specific structural changes. The hallmark of the initial stage is the division of the original liver parenchyma by centro-central or porto-portal septa. No significant vascular changes are observed in this stage. The advanced stage is characterized by several morphological alterations: (i) The main feature is the parenchymal extinction, with intact portal vein branches, hepatic artery branches, and biliary ductules; (ii) In the extinct areas we observed numerous loops in the ductular network, indicating the disruption of the hepato-biliary junctions; (iii) Although the ductular progenitor cells are able to generate hepatocytes via the budding process, the newly formed hepatocyte nodules cannot re-establish the original lobular architecture due to their disorganized growth. In conclusion, this regenerative process characteristic for the advanced stage, contributes to circulatory disorders, perpetuates parenchymal injury and may lead to the irreversibility of cirrhosis.

Down-Regulating the High Level of 17-Beta-Hydroxysteroid Dehydrogenase 13 Plays a Therapeutic Role for Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide, and there is no specific drug to treat it. Recent results showed that 17-beta-hydroxysteroid dehydrogenase type 13 (HSD17B13) is associated with liver diseases, but these conclusions are controversial. Here, we showed that HSD17B13 was more highly expressed in the livers of NAFLD patients, and high expression was induced in the livers of murine NAFLD models and cultural hepatocytes treated using various etiologies. The high HSD17B13 expression in the hepatocytes facilitated the progression of NAFLD by directly stabilizing the intracellular lipid drops and by indirectly activating hepatic stellate cells. When HSD17B13 was overexpressed in the liver, it aggravated liver steatosis and fibrosis in mice fed with a high-fat diet, while down-regulated the high expression of HSD17B13 by short hairpin RNAs produced a therapeutic effect in the NAFLD mice. We concluded that high HSD17B13 expression is a good target for the development of drugs to treat NAFLD.

Mesenchymal Stem Cells and Their Small Extracellular Vesicles as Crucial Immunological Efficacy for Hepatic Diseases

Mesenchymal stem cell small extracellular vesicles (MSC-sEVs) are a priority for researchers because of their role in tissue regeneration. sEVs act as paracrine factors and carry various cargos, revealing the state of the parent cells and contributing to cell–cell communication during both physiological and pathological circumstances. Hepatic diseases are mainly characterized by inflammatory cell infiltration and hepatocyte necrosis and fibrosis, bringing the focus onto immune regulation and other regulatory mechanisms of MSCs/MSC-sEVs. Increasing evidence suggests that MSCs and their sEVs protect against acute and chronic liver injury by inducing macrophages (MΦ) to transform into the M2 subtype, accelerating regulatory T/B (Treg/Breg) cell activation and promoting immunosuppression. MSCs/MSC-sEVs also prevent the proliferation and differentiation of T cells, B cells, dendritic cells (DCs), and natural killer (NK) cells. This review summarizes the potential roles for MSCs/MSC-sEVs, including immunomodulation and tissue regeneration, in various liver diseases. There is also a specific focus on the use of MSC-sEVs for targeted drug delivery to treat hepatitis.

The Chemokine System in Oncogenic Pathways Driven by Viruses: Perspectives for Cancer Immunotherapy

Simple Summary

Oncoviruses are viruses with oncogenic potential, responsible for almost 20% of human cancers worldwide. They are from various families, some of which belong to the microbial communities that inhabit several sites in the body of healthy humans. As a result, they most often establish latent infections controlled by the arsenal of human host responses that include the chemokine system playing key roles at the interface between tissue homeostasis and immune surveillance. Yet, chemokines and their receptors also contribute to oncogenic processes as they are targeted by the virus-induced deregulations of host responses and/or directly encoded by viruses. Thus, the chemokine system offers a strong rationale for therapeutic options, some few already approved or in trials, and future ones that we are discussing in view of the pharmacological approaches targeting the different functions of chemokines operating in both cancer cells and the tumor microenvironment.

Abstract

Chemokines interact with glycosaminoglycans of the extracellular matrix and activate heptahelical cellular receptors that mainly consist of G Protein-Coupled Receptors and a few atypical receptors also with decoy activity. They are well-described targets of oncogenic pathways and key players in cancer development, invasiveness, and metastasis acting both at the level of cancer cells and cells of the tumor microenvironment. Hence, they can regulate cancer cell proliferation and survival and promote immune or endothelial cell migration into the tumor microenvironment. Additionally, oncogenic viruses display the potential of jeopardizing the chemokine system by encoding mimics of chemokines and receptors as well as several products such as oncogenic proteins or microRNAs that deregulate their human host transcriptome. Conversely, the chemokine system participates in the host responses that control the virus life cycle, knowing that most oncoviruses establish asymptomatic latent infections. Therefore, the deregulated expression and function of chemokines and receptors as a consequence of acquired or inherited mutations could bias oncovirus infection toward pro-oncogenic pathways. We here review these different processes and discuss the anticancer therapeutic potential of targeting chemokine availability or receptor activation, from signaling to decoy-associated functions, in combination with immunotherapies.