The Effect of Treatment-Induced Viral Eradication on Cytokine and Growth Factor Expression in Chronic Hepatitis C

Liver Fibrosis Stages Affect Organic Cation Transporter 1/2 Activities in Hepatitis C Virus-Infected Patients

This study aims to evaluate the impact of liver fibrosis stages of chronic infection with hepatitis C virus (HCV) on the in vivo activity of organic cation transporters (hepatic OCT1 and renal OCT2) using metformin (MET) as a probe drug. Participants allocated in Group 1 (n = 15, mild to moderate liver fibrosis) or 2 (n = 13, advanced liver fibrosis and cirrhosis) received a single MET 50 mg oral dose before direct-acting antiviral (DAA) drug treatment (Phase 1) and 30 days after achieving sustained virologic response (Phase 2). OCT1/2 activity (MET AUC0-24) was found to be reduced by 25% when comparing the two groups in Phase 2 (ratio 0.75 (0.61-0.93), p < 0.05) but not in Phase 1 (ratio 0.81 (0.66-0.98), p > 0.05). When Phases 1 and 2 were compared, no changes were detected in both Groups 1 (ratio 1.10 (0.97-1.24), p > 0.05) and 2 (ratio 1.03 (0.94-1.12), p > 0.05). So, this study shows a reduction of approximately 25% in the in vivo activity of OCT1/2 in participants with advanced liver fibrosis and cirrhosis after achieving sustained virologic response and highlights that OCT1/2 in vivo activity depends on the liver fibrosis stage of chronic HCV infection.

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.

Injecting drug use and hepatitis C virus infection independently increase biomarkers of inflammatory disease risk which are incompletely restored by curative direct-acting antiviral therapy

Background

Hepatitis C virus (HCV) infections are more prevalent in people who inject drugs (PWID) who often experience additional health risks. HCV induces inflammation and immune alterations that contribute to hepatic and non-hepatic morbidities. It remains unclear whether curative direct acting antiviral (DAA) therapy completely reverses immune alterations in PWID.

Methods

Plasma biomarkers of immune activation associated with chronic disease risk were measured in HCV-seronegative (n=24) and HCV RNA+ (n=32) PWID at baseline and longitudinally after DAA therapy. Adjusted generalised estimating equations were used to assess longitudinal changes in biomarker levels. Comparisons between community controls (n=29) and HCV-seronegative PWID were made using adjusted multiple regression modelling.

Results

HCV-seronegative PWID exhibited significantly increased levels of inflammatory biomarkers including soluble (s) TNF-RII, IL-6, sCD14 and sCD163 and the diabetes index HbA1c as compared to community controls. CXCL10, sTNF-RII, vascular cell adhesion molecule-1 and lipopolysaccharide binding protein (LBP) were additionally elevated in PWID with viremic HCV infection as compared to HCV- PWID. Whilst curative DAA therapy reversed some biomarkers, others including LBP and sTNF-RII remained elevated 48 weeks after HCV cure.

Conclusion

Elevated levels of inflammatory and chronic disease biomarkers in PWID suggest an increased risk of chronic morbidities such as diabetes and cardiovascular disease. HCV infection in PWID poses an additional disease burden, amplified by the incomplete reversal of immune dysfunction following DAA therapy. These findings highlight the need for heightened clinical surveillance of PWID for chronic inflammatory diseases, particularly those with a history of HCV infection.

The Role of Stem Cell Factor, Epidermal Growth Factor and Angiopoietin-2 in HBV, HCV, HCC and NAFLD

Growth factors play a significant role in the immunopathogenesis of liver diseases, especially in liver fibrosis and cirrhosis. They can also play a role in liver regeneration and tissue repair. The regenerative capacity of the liver has been well established. Molecular mechanisms leading to regeneration involve a complex network of diverse molecules. Chronic liver injury leads to the dysregulation of regenerative mechanisms in the liver that, in addition to molecular oncogenesis, lead to uncontrolled cell proliferation and development of hepatocellular carcinoma (HCC). Stem cell factor (SCF), epidermal growth factor (EGF) and Angiopietin-2 (Ang-2) have been shown to be extremely important in the pathogenesis of liver diseases, and given their role in hepatitis B (HBV) or C virus (HCV), HCC and nonalcoholic fatty liver disease (NAFLD), they seem to be potential targets for future research into antifibrotic drugs. The role of SCF receptor c-kit in the liver is debatable, as it has impact on both liver regeneration and liver disease. EGF is a potential indicator of the survival of patients with HCC and can be a biomarker and therapeutic target structure in HCC. Further research is needed to investigate the potential role of Ang-2 for NAFLD associated with liver damage as a non-invasive circulating biomarker.

Distinct Expression Patterns of Genes Coding for Biological Response Modifiers Involved in Inflammatory Responses and Development of Fibrosis in Chronic Hepatitis C: Upregulation of SMAD-6 and MMP-8 and Downregulation of CAV-1, CTGF, CEBPB, PLG, TIMP-3, MMP-1, ITGA-1, ITGA-2 and LOX

Background and Objectives: The aim of this study was to analyze the expression of genes on transcriptomic levels involved in inflammatory immune responses and the development of fibrosis in patients with chronic hepatitis C. Materials and Methods: Expression patterns of 84 selected genes were analyzed with real-time quantitative RT PCR arrays in the peripheral blood of treatment-naive patients with chronic hepatitis C and healthy controls. The panel included pro- and anti-fibrotic genes, genes coding for extracellular matrix (EMC) structural constituents and remodeling enzymes, cell adhesion molecules, inflammatory cytokines, chemokines and growth factors, signal transduction members of the transforming growth factor- beta (TGF-ß) superfamily, transcription factors, and genes involved in epithelial to mesenchymal transition. Results: The expression of SMAD-6 coding for a signal transduction TGF-beta superfamily member as well as MMP-8 coding for an ECM protein were significantly increased in CHC patients compared with controls. Conclusions: Chronic hepatitis C was also characterized by a significant downregulation of a set of genes including CAV-1, CTGF, TIMP-3, MMP-1, ITGA-1, LOX, ITGA-2, PLG and CEBPB encoding various biological response modifiers and transcription factors. Our results suggest that chronic hepatitis C is associated with distinct patterns of gene expression modulation in pathways associated with the regulation of immune responses and development of fibrosis.