Elevation of interleukin 6 levels in patients with chronic hepatitis due to hepatitis C virus

Reverse vaccinology approach for identification of epitopes from E1 protein as peptide vaccine against HCV: A proof of concept

The development of effective vaccines against Hepatitis C Virus (HCV) remains a global health priority and challenge. In this study, we employed an integrative approach combining computational epitope prediction with experimental validation to identify immunogenic peptides targeting the E1 glycoprotein of HCV. In the present report, computational data from various epitope prediction algorithms such as IEDB and SYFPEITHI, followed by molecular dynamics (MD) simulations and immuno-informatics analysis is presented. Through computational screening, we identified potential epitope candidates, with QVRNSSGLY (P3) and QLFTFSPRH (P7) emerging as promising candidates. MD simulations revealed stable interactions between these epitopes and MHC molecule, further validated by free energy estimations using MMPBSA method. Immuno-informatics analysis supported these findings, showing high binding potential and immunogenicity scores for the selected peptides. Subsequent synthesis and characterization of epitope peptides confirmed their structural integrity and purity required for conducting immune activation assays. Experimental immunological assays carried out in this study involved epitope peptide induced activation of CD8 + and CD4 + T cells from healthy human subjects and HCV- recovered patients. Data from experimental validation revealed significant cytokine release upon exposure to epitope peptides, particularly TNF-a, IL-6, and GM-CSF, indicative of robust immune responses. Notably, peptides P3 and P7 exhibited the most pronounced cytokine induction profiles, underscoring their potential as vaccine candidates. Further investigations addressing the mechanism of action of these epitope peptides under preclinical and clinical settings may help in developing effective vaccine against HCV.

Direct-Acting Antiviral Drugs Reduce Fibromyalgia Symptoms in Patients with Chronic Hepatitis C

Background Fibromyalgia (FM) is a complex disorder characterized by chronic widespread pain and significant patient burden. Patients with chronic hepatitis C are reportedly predisposed to the development of FM. Direct-acting antiviral drugs (DAA) achieved a remarkable therapeutic efficacy in CHC patients. We therefore investigated the impact of DAA on FM symptoms in CHC patients. Methods We enrolled consecutive CHC patients who received DAA. FM symptoms were evaluated based on the 2016 American College of Rheumatology (ACR) fibromyalgia scale at baseline and 12 and 24 weeks after cessation of DAA therapy. Logistic regression was performed to determine the influence of HCV on FM at baseline. We also recruited individuals who underwent a health checkup examination as the control group, and calculated the standardized prevalence ratio of FM in CHC patients. Comparisons of fibromyalgia in different time points were undertaken using the Wilcoxon signed-rank test. Results A total of 33 CHC patients (15 males and 18 females) and 402 controls were recruited. All CHC patients achieved sustained virological response. Two (6%) patients and two (0.5%) controls fulfilled the diagnostic criteria for FM, and the standardized prevalence ratio was 23.9 in CHC patients. Logistic regression also showed increased odds for FM in CHC patients after adjusting for age and sex (OR: 14.4; 95%CI: 1.6, 128.0). In addition, their fibromyalgianess scale decreased at 12 and 24 weeks after DAA therapy. In conclusion, CHC patients were more likely to develop FM. Implementation of DAA therapy might improve FM symptoms in these patients.

Understanding the outcomes of COVID-19 - does the current model of an acute respiratory infection really fit?

Although coronavirus disease 2019 (COVID-19) is regarded as an acute, resolving infection followed by the development of protective immunity, recent systematic literature review documents evidence for often highly prolonged shedding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in respiratory and faecal samples, periodic recurrence of PCR positivity in a substantial proportion of individuals and increasingly documented instances of reinfection associated with a lack of protective immunity. This pattern of infection is quite distinct from the acute/resolving nature of other human pathogenic respiratory viruses, such as influenza A virus and respiratory syncytial virus. Prolonged shedding of SARS-CoV-2 furthermore occurs irrespective of disease severity or development of virus-neutralizing antibodies. SARS-CoV-2 possesses an intensely structured RNA genome, an attribute shared with other human and veterinary coronaviruses and with other mammalian RNA viruses such as hepatitis C virus. These are capable of long-term persistence, possibly through poorly understood RNA structure-mediated effects on innate and adaptive host immune responses. The assumption that resolution of COVID-19 and the appearance of anti-SARS-CoV-2 IgG antibodies represents virus clearance and protection from reinfection, implicit for example in the susceptible-infected-recovered (SIR) model used for epidemic prediction, should be rigorously re-evaluated.

Inflammatory and cardiovascular diseases biomarkers in chronic hepatitis C virus infection: A review

Hepatitis C virus (HCV) infects 180 million people worldwide and over 4 million people in the United States. HCV infection is a major cause of chronic liver disease and is recognized as a risk factor for clinical cardiovascular disease (CVD). Many studies have shown increased prevalence of cardiac and inflammatory biomarkers in patients with chronic HCV infection (CHC), and though these markers may be used to risk stratify people for cardiac disease in the general population their role in the HCV population is unknown. Patients with CHC have elevated cardiac and inflammatory biomarkers compared to noninfected controls which may play a role in CVD risk stratification. We undertook a systematic review of inflammatory and cardiac biomarkers in people with HCV infection with a focus on the effect of CHC on serum levels of these markers and their utility as predictors of CVD in this population. Medline, EMBASE, and Cochrane databases were searched for relevant articles until June 2019. A total of 2430 results were reviewed with 115 studies included. Our review revealed that HCV infection significantly alters serum levels of markers of inflammation, endothelial function, and cardiac dysfunction prior to HCV treatment, and some of which may change in response to HCV therapy. Current risk stratification tools for development of CVD in the general population may not account for the increased inflammatory markers that appear to be elevated among HCV‐infected patients contributing to increased CVD risk.

In Chronic Hepatitis C Infection, Myeloid-Derived Suppressor Cell Accumulation and T Cell Dysfunctions Revert Partially and Late After Successful Direct-Acting Antiviral Treatment

Chronic HCV infection is characterized by several immunological alterations, such as the accumulation of suppressor cells and of hyperactivated T lymphocytes. However, it is unclear whether direct-acting antiviral (DAA)-mediated HCV clearance restores immune dysfunctions. We performed a phenotypic characterization by flow cytometry of different immune cell subsets, including monocytic myeloid-derived suppressor cells (M-MDSCs) and T lymphocytes in 168 patients with persistent HCV infection not treated, under DAA therapies and sustained virological responders. Chronic HCV infection prompted the accumulation of M-MDSCs independently of patient and clinical characteristics, and altered their metabolic properties. HCV RNA was undetectable in the majority of patients just after few weeks of DAA therapy, whereas M-MDSC levels normalized only 6 months after therapy. In addition, HCV infection deeply perturbed the T cell compartment since a re-distribution of memory CD4⁺ and CD8⁺ T cells was observed at the expenses of naïve cells, and memory T lymphocytes displayed increased activation. Notably, these features were only partially restored by DAA therapies in the CD4, but not in the CD8, compartment as high immune activation levels persisted in the terminally differentiated memory CD8⁺ T cells even more than 1 year after sustained virological response. Together, these results suggest that successful DAA therapies do not lead to full immunological reconstitution as fast as viral clearance.

Strategies to Circumvent Host Innate Immune Response by Hepatitis C Virus

Innate immune responses generate interferons, proinflammatory cytokines, complement activation, and natural killer (NK) cell response. Ultimately, this leads to the induction of a robust virus-specific adaptive immunity. Although the host innate immune system senses and responds to eliminate virus infection, hepatitis C virus (HCV) evades immune attack and establishes persistent infection within the liver. Spontaneous clearance of HCV infection is associated with a prompt induction of innate immunity generated in an infected host. In this review, we have highlighted the current knowledge of our understanding of host⁻HCV interactions, especially for endogenous interferon production, proinflammatory response, NK cell response, and complement activation, which may impair the generation of a strong adaptive immune response for establishment of chronicity. The information may provide novel strategies in augmenting therapeutic intervention against HCV.

Clinical Significance of Polymorphisms in Immune Response Genes in Hepatitis C-Related Hepatocellular Carcinoma

Background and Aims: Polymorphisms in the immune response genes can contribute to clearance of hepatitis C virus (HCV) infection but also mediate liver inflammation and cancer pathogenesis. This study aimed to investigate the association of polymorphisms in PD-1 (PDCD1), IFNL3 (IL28B), and TLR2 immune related genes in chronic HCV patients with different hepatic and lymphoproliferative HCV-related diseases. Methods: Selected PDCD1, IFNL3, and TLR2 genes were tested by molecular approaches in 450 HCV-positive patients with increasing severity of underlying liver diseases [including chronic infection (CHC), cirrhosis and hepatocellular carcinoma (HCC)], in 238 HCV-positive patients with lymphoproliferative diseases [such as cryoglobulinemia and non-Hodgkin lymphoma (NHL)] and in 94 blood donors (BD). Results: While the rs12979860 IFNL3 T allele was found a good marker associated with HCV-outcome together with the rs111200466 TLR2 del variant, the rs10204525 PD-1.6 A allele was found to have an insignificant role in patients with HCV-related hepatic disorders. Though in Asian patients the combination of IFNL3 and PD-1.6 markers better define the HCV-related outcomes, in our series of Caucasian patients the PD-1.6 A-allele variant was observed very rarely. Conclusion: Differences in the incidence of HCV-related HCC and clinical response between Asians and Europeans may be partially due to the distribution of PD-1.6 genotype that we found divergent between these two populations. On the other hand, we confirmed in this study that the polymorphic variants within IFNL3 and TLR2 immune response genes are significantly associated with HCV-related disease progression in our cohort of Italian patients.

Proliferation‑inhibiting pathways in liver regeneration (Review)

Liver regeneration, an orchestrated process, is the primary compensatory mechanism following liver injury caused by various factors. The process of liver regeneration consists of three stages: Initiation, proliferation and termination. Proliferation‑promoting factors, which stimulate the recovery of mitosis in quiescent hepatocytes, are essential in the initiation and proliferation steps of liver regeneration. Proliferation‑promoting factors act as the 'motor' of liver regeneration, whereas proliferation inhibitors arrest cell proliferation when the remnant liver reaches a suitable size. Certain proliferation inhibitors are also expressed and activated in the first two steps of liver regeneration. Anti‑proliferation factors, acting as a 'brake', control the speed of proliferation and determine the terminal point of liver regeneration. Furthermore, anti‑proliferation factors function as a 'steering‑wheel', ensuring that the regeneration process proceeds in the right direction by preventing proliferation in the wrong direction, as occurs in oncogenesis. Therefore, proliferation inhibitors to ensure safe and stable liver regeneration are as important as proliferation‑promoting factors. Cytokines, including transforming growth factor‑β and interleukin‑1, and tumor suppressor genes, including p53 and p21, are important members of the proliferation inhibitor family in liver regeneration. Certain anti‑proliferation factors are involved in the process of gene expression and protein modification. The suppression of liver regeneration led by metabolism, hormone activity and pathological performance have been reviewed previously. However, less is known regarding the proliferation inhibitors of liver regeneration and further investigations are required. Detailed information regarding the majority of known anti‑proliferation signaling pathways also remains fragmented. The present review aimed to understand the signalling pathways that inhbit proliferation in the process of liver regeneration.

Disease severity and erythropoiesis in chronic hepatitis C

BACKGROUND/AIMS

The erythropoiesis in hepatitis C virus infection is unclear. We aimed to evaluate the erythropoietic components in chronic hepatitis C (CHC) patients.

METHODS

The red blood cell (RBC) components, serum erythropoietin (EPO) levels, and their relationship to clinical characteristics were evaluated between 124 age-matched and sex-matched healthy controls and 248 histology-proven CHC patients.

RESULTS

Chronic hepatitis C patients had significantly higher serum levels of EPO (1.44 ± 0.36 log mIU/mL versus 1.03 ± 0.31 log mIU/mL, P < 0.0001) and lower hemoglobin (Hb) concentrations (14.6 ± 1.4 g/dL versus 15.3 ± 1.2 g/dL, P < 0.001) as compared with healthy controls. Among the CHC patients, the serum EPO level was negatively associated with the Hb concentration (β = -0.227; 95% confidence intervals [CI]: -0.09-0.027; P < 0.001) and RBC counts (β = -0.204; 95% CI: -0.245-0.061; P = 0.001) and was positively correlated with necroinflammatory activity (β = 0.201; 95% CI: 0.009-0.046; P = 0.003) and fibrosis (β = 0.143; 95% CI: 0.003-0.076; P = 0.04) of liver histopathology. For non-cirrhotic CHC patients, the severity of liver necroinflammatory activity was positively correlated with the reticulocyte and serum EPO levels (P = 0.001 and 0.008, respectively), and negatively related to the RBC counts (P = 0.03). Using stepwise multivariate linear regression analysis, the grade of necroinflammatory activity was positive (β = 0.214; 95% CI: 0.046-0.209, P = 0.002), whereas the Hb concentration was inversely (β = -0.205; 95% CI: -0.09-0.018, P = 0.004) associated with the serum EPO levels in CHC patients.

CONCLUSIONS

The disease activity in CHC patients had a negative impact on erythropoiesis with compensatory higher but blunted EPO responses.

HCV-induced regulatory alterations of IL-1β, IL-6, TNF-α, and IFN-ϒ operative, leading liver en-route to non-alcoholic steatohepatitis

Over the course of time, Hepatitis C has become a universal health menace. Its deleterious effects on human liver encompass a lot of physiological, genetic as well as epigenetic alterations. Fatty liver (Hepatic steatosis) is an inflammation having multifactorial ancestries; one of them is HCV (steatohepatitis). HCV boosts several cellular pathways involving up-regulation of a number of cytokines. Current study reviews the regulation of some selective key cytokines during HCV infection, to help generate an improved understanding of their role. These cytokines, IL-1β, IL-6, TNF-α, and IFN-ϒ, are inflammatory markers of the body. These particular markers along with others help hepatocytes against viral infestation. However, recently, their association has been found in degradation of liver on the trail heading to non-alcoholic steatohepatitis (NASH). Consequently, the disturbance in their equilibrium has been repeatedly reported during HCV infection. Quite a number of findings are affirming their up-regulation. Although these cell markers are stimulated by hepatocytes as their standard protection mechanism, but modern studies have testified the paradoxical nature of this defense line. Nevertheless, direct molecular or epigenetic research is needed to question the actual molecular progressions and directions commanding liver to steatosis, cirrhosis, or eventually HCC (Hepatocellular Carcinoma).

Higher CD163 levels are associated with insulin resistance in hepatitis C virus-infected and HIV-infected adults

OBJECTIVES

HIV/hepatitis C virus (HCV) coinfection is associated with insulin resistance, but the mechanism is unclear. We hypothesized that intestinal epithelial damage and the consequent monocyte/macrophage activation and inflammation explain this perturbation.

DESIGN

Cross-sectional study of 519 adults (220 HIV+/HCV-; 64 HIV-/HCV+; 89 HIV+/HCV+; 146 HIV-/HCV-).

METHODS

We used multivariable linear regression to evaluate associations of HIV and HCV with the homeostasis model assessment of insulin resistance (HOMA-IR) and if intestinal fatty (FA) acid binding protein (I-FABP, a marker of gut epithelial integrity), soluble CD14 (sCD14) and soluble CD163 (sCD163) (markers of monocyte/macrophage activation), and IL-6 (an inflammatory cytokine) mediated this association.

RESULTS

HIV+/HCV+ and HIV-/HCV+ had greater demographic-adjusted HOMA-IR [mean (95% confidence interval (CI)): 1.96 (1.51, 2.54) and 1.65 (1.22, 2.24)] than HIV+/HCV- and HIV-/HCV-[1.41 (1.18, 1.67) and 1.44 (1.17, 1.75), respectively]. After additional adjustment for lifestyle and metabolic factors, HIV+/HCV+ remained associated with 36% (95% CI: 4, 80%) greater HOMA-IR relative to HIV-/HCV-, whereas HIV-/HCV+ and HIV+/HCV- had smaller differences. Adjustment for sCD163 substantially attenuated the difference between HIV+/HCV+ and HIV-/HCV-; adjustment for I-FABP, sCD14, and IL-6 had little effect. Higher sCD163 was independently associated with 19% (95% CI: 7, 33%), 26% (95% CI: 15, 39%), 25% (95% CI: 14, 37%), and 23% (95% CI: 11, 36%) greater HOMA-IR in HIV+/HCV+, HIV-/HCV+, HIV+/HCV-, and HIV-/HCV- (all estimates per doubling of sCD163). I-FABP, sCD14, and IL-6 were not associated with HOMA-IR.

CONCLUSION

HIV/HCV coinfection is associated with greater HOMA-IR, even after controlling for demographic, lifestyle, and metabolic factors. sCD163, which appears independent of intestinal epithelial damage and inflammation, partly explains this association. Our findings that the association of sCD163 with HOMA-IR occurred even in the absence of HIV and HCV, indicate that viral and nonviral factors affect sCD163 levels. Its role in insulin resistance needs elucidation.

Lack of Any Relationship Between Circulating Autoantibodies and Interleukin–6 Levels in Egyptian Patients Infected with the Hepatitis C Virus

Introduction: Elevated serum interleukin (IL) 6 has been reported in patients infected with the hepatitis C virus (HCV), but it remains debatable whether this influences the production of autoantibodies and the biochemical profile of HCV disease. Therefore, this current study was conducted to evaluate the relationship between IL-6 and circulating autoantibody levels in HCV positive patients. Methods: Levels of IL-6 in serum samples from 102 patients with HCV and 103 normal controls were determined by enzyme linked immunosorbent assay (ELISA). Autoantibodies were detected by immunofluorescence. Results: Levels of IL-6 were significantly higher (p=0.028) in patients infected with (HCV) compared with normal group. Autoantibodies were noted in in 43.1% of the patients; of these, 23.5% featured anti-nuclear antibodies (ANA+), 16.7% anti-smooth muscle antibodies (ASMA+), 7.8% anti-mitochondrial antibodies (AMA+), 17.6% anti-parietal cell antibodies (APCA+), 7.8% anti canalicular antibodies, and 2.9% anti reticulin antibodies (ARA+). No patients were found to be positive for anti-brush border antibodies (ABBA) or anti-ribosomal antibodies. (ARiA). No links with IL-6 levels were apparent. Conclusions: IL-6 levels are increased in patients infected with HCV disease and could influence the production of autoantibodies. However, this study did not provide evidence of a specific relationship between IL6 and circulating autoantibodies in such cases.

The impact of IL-6 and IL-28B gene polymorphisms on treatment outcome of chronic hepatitis C infection among intravenous drug users in Croatia

Background

Several genes and their single nucleotide polymorphisms (SNPs) are associated with either spontaneous resolution of hepatitis C infection or better treatment-induced viral clearance. We tested a cohort of intravenous drug users (IVDU) diagnosed with chronic hepatitis C virus (HCV) for treatment response and its association with the SNPs in the interleukin-6 (rs1800795-IL6) and the interleukin-28B (rs12979860-IL28B) genes.

Methods

The study included 110 Croatian IVDU positive for anti-HCV antibody. Genotyping was performed by polymerase chain reaction (PCR) based approach. Patients were treated by standard pegylated-interferon/ribavirin and followed throughout a period of four years, during which sustained virological response (SVR) was determined. All data were analysed with statistical package SPSS 19.0 (IBM Corp, Armonk, NY, USA) and PLINK v1.07 software.

Results

Patients showed a significantly better response to treatment according to the number of copies of the C allele carried at rs1800795-IL6 (P = 0.034). All but one of the patients with CC genotype achieved SVR (93%), whereas the response rate of patients with GG genotype was 64%. The association of rs1800795-IL6 with SVR status remained significant after further adjustment for patients’ age, fibrosis staging, and viral genotype (OR 2.15, 95% CI 1.16–4.68, P = 0.019). Distributions of allele frequencies at the locus rs12979860-IL28B among the study cohort and the underlying general population were suggestive of a protective effect of CC genotype in acquiring chronic hepatitis C in the Croatian IVDU population.

Discussion

The rs1800795-IL6 polymorphism is associated with positive response to treatment in IVDU patients positive for HCV infection. A protective role of rs12979860-IL28B CC genotype in acquiring chronic hepatitis C is suggested for Croatian IVDU population.

Hepatitis C virus infection and pain sensitivity in patients on methadone or buprenorphine maintenance therapy for opioid use disorders

BACKGROUND

Patients with opioid use disorders on opioid agonist therapy (OAT) have lower pain tolerance compared to controls. While chronic viral infections such as HCV and HIV have been associated with chronic pain in this population, no studies have examined their impact on pain sensitivity.

METHODS

We recruited 106 adults (41 uninfected controls; 40 HCV mono-infected; and 25 HCV/HIV co-infected) on buprenorphine or methadone to assess whether HCV infection (with or without HIV) was associated with increased experimental pain sensitivity and self-reported pain. The primary outcome was cold pain tolerance assessed by cold-pressor test. Secondary outcomes were cold pain thresholds, wind-up ratios to repetitive mechanical stimulation (i.e., temporal summation) and acute and chronic pain. Multivariable regression models evaluated associations between viral infection status and outcomes, adjusting for other factors.

RESULTS

No significant differences were detected across groups for primary or secondary outcomes. Adjusted mean cold pain tolerance was 25.7 (uninfected controls) vs. 26.8 (HCV mono-infection) vs. 25.3 (HCV/HIV co-infection) seconds (global p-value=0.93). Current pain appeared more prevalent among HCV mono-infected (93%) compared to HCV/HIV co-infected participants (76%) and uninfected controls (80%), as did chronic pain (77% vs. 64% vs. 61%, respectively). However, differences were not statistically significant in multivariable models.

CONCLUSION

This study did not detect an association between HCV infection and increased sensitivity to pain among adults with and without HIV who were treated with buprenorphine or methadone for opioid use disorders. Results reinforce that pain and hyperalgesia are common problems in this population.

Hepatitis C virus infection and type 1 and type 2 diabetes mellitus

Hepatitis C virus (HCV) infection and diabetes mellitus are two major public health problems that cause devastating health and financial burdens worldwide. Diabetes can be classified into two major types: type 1 diabetes mellitus (T1DM) and T2DM. T2DM is a common endocrine disorder that encompasses multifactorial mechanisms, and T1DM is an immunologically mediated disease. Many epidemiological studies have shown an association between T2DM and chronic hepatitis C (CHC) infection. The processes through which CHC is associated with T2DM seem to involve direct viral effects, insulin resistance, proinflammatory cytokines, chemokines, and other immune-mediated mechanisms. Few data have been reported on the association of CHC and T1DM and reports on the potential association between T1DM and acute HCV infection are even rarer. A small number of studies indicate that interferon-α therapy can stimulate pancreatic autoimmunity and in certain cases lead to the development of T1DM. Diabetes and CHC have important interactions. Diabetic CHC patients have an increased risk of developing cirrhosis and hepatocellular carcinoma compared with non-diabetic CHC subjects. However, clinical trials on HCV-positive patients have reported improvements in glucose metabolism after antiviral treatment. Further studies are needed to improve prevention policies and to foster adequate and cost-effective programmes for the surveillance and treatment of diabetic CHC patients.

Increased baseline proinflammatory cytokine production in chronic hepatitis C patients with rapid virological response to peginterferon plus ribavirin

Background

Chronic hepatitis C (CHC) patients achieving rapid virological response (RVR) on PEG-IFN/ribavirin (P/R) therapy have high chance of sustained virological response (SVR). To analyze host immunological factors associated with RVR, viral kinetics, phenotype distribution and Th1/Th2 cytokine production by peripheral blood mononuclear cells (PBMC) were studied prior to and during P/R therapy.

Methods

TNF-α, IFN-γ, IL-2, IL-6, IL-4 and IL-10 production by PBMC were measured after Toll-like receptor 4 (TLR-4) or phorbol myristate acetate/Ionomycin stimulation in 20 healthy controls and in 50 CHC patients before receiving and during P/R therapy. RVR was achieved by 14, complete early virological response (cEVR) by 19 patients and 17 patients were null-responders (NR).

Results

Patients with RVR showed an increased baseline TNF-α and IL-6 production by TLR-4 activated monocytes and increased IFN-γ, decreased IL-4 and IL-10 production by lymphocytes compared to non-RVR patients. SVR was also associated with increased baseline TNF-α production and decreased IL-10 levels compared to patients who did not achieve SVR. Baseline IL-2 production was higher in cEVR compared to NR patients. Antiviral treatment increased TNF-α, IL-6 production by monocytes and IFN-γ secretion by lymphocytes and decreased IL-4 and IL-10 production by lymphocytes in cEVR compared to NR patients.

Conclusion

RVR was associated with increased baseline proinflammatory cytokine production by TLR-4 stimulated monocytes and by activated lymphocytes. In null-responders and in patients who did not achieve SVR both TLR-4 sensing function and proinflammatory cytokine production were impaired, suggesting that modulation of TLR activity and controlled induction of inflammatory cytokine production may provide further therapeutic strategy for CHC patients non-responding to P/R treatment.

New approaches to sepsis: molecular diagnostics and biomarkers

Sepsis is among the most common causes of death in hospitals. It arises from the host response to infection. Currently, diagnosis relies on nonspecific physiological criteria and culture-based pathogen detection. This results in diagnostic uncertainty, therapeutic delays, the mis- and overuse of antibiotics, and the failure to identify patients who might benefit from immunomodulatory therapies. There is a need for new sepsis biomarkers that can aid in therapeutic decision making and add information about screening, diagnosis, risk stratification, and monitoring of the response to therapy. The host response involves hundreds of mediators and single molecules, many of which have been proposed as biomarkers. It is, however, unlikely that one single biomarker is able to satisfy all the needs and expectations for sepsis research and management. Among biomarkers that are measurable by assays approved for clinical use, procalcitonin (PCT) has shown some usefulness as an infection marker and for antibiotic stewardship. Other possible new approaches consist of molecular strategies to improve pathogen detection and molecular diagnostics and prognostics based on transcriptomic, proteomic, or metabolic profiling. Novel approaches to sepsis promise to transform sepsis from a physiologic syndrome into a group of distinct biochemical disorders and help in the development of better diagnostic tools and effective adjunctive sepsis therapies.

Association of insulin resistance, viral load, and adipokine levels with liver histology in patients with chronic hepatitis C: an observational, multicenter study in Turkey

OBJECTIVE

To evaluate the association of insulin resistance (IR), viral load, and adipokine levels with liver histology in patients with chronic hepatitis C (CHC).

PATIENTS AND METHODS

In this noninterventional, multicenter study carried out at 11 infectious diseases clinics in Turkey, 103 CHC patients [mean (SD) age: 50.2 (11.0) years, 60 (58.3%) women] planned to be treated by ribavirin and peginterferon-α2a were included. Data on hepatic fibrosis and steatosis, IR, viral load, and hepatitis C virus-RNA genotyping, adipokine, and cytokine levels were collected.

RESULTS

The mean (SD) Knodell score was 8.1 (3.6); grade I steatosis was evident in 46 (44.7%) patients and IR was identified in 56 (54.9%). There was a significant positive correlation of the homeostasis model assessment-IR index with Knodell fibrosis (r=0.235; P=0.027) and hepatic steatosis (r=0.435; P<0.001). There was a significant positive correlation of leptin levels with Knodell fibrosis (r=0.265; P=0.013) and hepatic activity index (r=0.218; P=0.041). Hepatic steatosis was correlated negatively with adiponectin (r=-0.320; P=0.001) and positively with leptin (r=-0.368; P<0.001) levels. Logistic regression analysis showed that increase in age [odds ratio (OR), 1.056; 95% confidence interval (CI), 1.005-1.110; P=0.030] was the only significant predictor of hepatic fibrosis (OR, 1.056; 95% CI, 1.005-1.110; P=0.030), whereas increase in age (OR, 1.066; 95% CI, 1.006-1.130; P=0.030), the presence of IR (OR, 5.621; 95% CI, 1.547-20.425; P=0.009), and decrease in adiponectin levels (OR, 0.808; 95% CI, 0.682-0.957; P=0.013) were the significant predictors of hepatic steatosis.

CONCLUSION

Our findings indicate a significant relationship of hepatic fibrosis and hepatic steatosis with IR and leptin levels, but not with the viral load in Turkish patients with CHC.

Efficacy of MK615 for the treatment of patients with liver disorders

AIM: To investigate the hepatoprotective effect of MK615, a Japanese apricot extract, in an animal model, and its clinical therapeutic effect.

METHODS: Wistar rats were administered physiological saline (4 mL/kg) or MK615 solution (4 mL/kg) for 7 d. On the sixth d, acute hepatic injury was induced by administering a single intraperitoneal injection (ip) of D-galactosamine hydrochloride (D-GalN) (600 mg/kg). Plasma levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined, and liver tissues were used for histopathological analysis. Fifty-eight patients with liver disorders [hepatitis C (n = 40), non-alcoholic fatty liver disease (n = 15), and autoimmune liver disease (n = 3)] were orally administered commercially available Misatol ME-containing MK615 (13 g/d) daily for 12 wk. Blood and urine were sampled immediately before and 6 wk, 12 wk, and 16 wk after the start of intake to measure various biochemical parameters. The percentage change in ALT and AST levels after 12 wk from the pre-intake baseline served as a primary endpoint.

RESULTS: D-GalN effectively induced acute hepatic injury in the rats. At 48 h after the ip injection of D-GalN, the plasma levels of ALT (475.6 ± 191.5 IU/L vs 225.3 ± 194.2 IU/L, P < 0.05) and AST (1253.9 ± 223.4 IU/L vs 621.9 ± 478.2 IU/L, P < 0.05) in the MK615 group were significantly lower than the control group. Scattered single cell necrosis, loss of hepatocytes, and extensive inflammatory cell infiltration were observed in hepatic tissue samples collected from the control group. However, these findings were less pronounced in the group receiving MK615. At the end of the clinical study, serum ALT and AST levels were significantly decreased compared with pre-intake baseline levels from 103.5 ± 58.8 IU/L to 71.8 ± 39.3 IU/L (P < 0.05) and from 93.5 ± 55.6 IU/L to 65.5 ± 34.8 IU/L (P < 0.05), respectively. A reduction of ≥ 30% from the pre-study baseline ALT level was observed in 26 (45%) of the 58 patients, while 25 (43%) patients exhibited similar AST level reductions. The chronic hepatitis C group exhibited significant ALT and AST level reductions from 93.4 ± 51.1 IU/L to 64.6 ± 35.1 IU/L (P < 0.05) and from 94.2 ± 55.5 IU/L to 67.2 ± 35.6 IU/L (P < 0.05), respectively. A reduction of ≥ 30% from the pre-study baseline ALT level was observed in 20 (50%) of the 40 patients. ALT levels in both the combined ursodeoxycholic acid (UDCA) treatment and the UDCA uncombined groups were significantly lower after Misatol ME administration. MK615 protected hepatocytes from D-GalN-induced cytotoxicity in rats. Misatol ME decreased elevated ALT and AST levels in patients with liver disorders.

CONCLUSION: These results suggest that MK615 and Misatol ME are promising hepatoprotective agents for patients with liver disorders.

Lentiviral vector-mediated down-regulation of IL-17A receptor in hepatic stellate cells results in decreased secretion of IL-6

AIM: To investigate the mechanism of interleukin (IL)-6 secretion through blocking the IL-17A/IL-17A receptor (IL-17RA) signaling pathway with a short hairpin RNA (shRNA) in hepatic stellate cells (HSCs) in vitro.

METHODS: HSCs were derived from the livers of adult male Sprague-Dawley rats. IL-6 expression was evaluated using real-time quantitative polymerase chain reaction and enzyme linked immunosorbent assay. The phosphorylation activity of p38 mitogen activated protein kinases (MAPK) and extracellular regulated protein kinases (ERK) 1/2 upon induction by IL-17A and suppression by IL-17RA shRNA were examined using Western blotting.

RESULTS: IL-6 expression induced by IL-17A was significantly increased compared to control in HSCs (P < 0.01 in a dose-dependent manner). Suppression of IL-17RA using lentiviral-mediated shRNA inhibited IL-6 expression induced by IL-17A compared to group with only IL-17A treatment (1.44 ± 0.17 vs 4.07 ± 0.43, P < 0.01). IL-17A induced rapid phosphorylation of p38 MAPK and ERK1/2 after 5 min exposure, and showed the strongest levels of phosphorylation of p38 MAPK and ERK1/2 at 15 min in IL-17A-treated HSCs. IL-6 mRNA expression induced by IL-17A (100 ng/mL) for 3 h exposure was inhibited by preincubation with specific inhibitors of p38 MAPK (SB-203580) and ERK1/2 (PD-98059) compared to groups without inhibitors preincubation (1.67 ± 0.24, 2.01 ± 0.10 vs 4.08 ± 0.59, P < 0.01). Moreover, Lentiviral-mediated IL-17RA shRNA 1 inhibited IL-17A-induced IL-6 mRNA expression compared to random shRNA in HSCs (1.44 ± 0.17 vs 3.98 ± 0.68, P < 0.01). Lentiviral-mediated IL-17RA shRNA 1 inhibited phosphorylation of p38 MAPK and ERK1/2 induced by 15 min IL-17A (100 ng/mL) exposure.

CONCLUSION: Down-regulation of the IL-17RA receptor by shRNA decreased IL-6 expression induced by IL-17A via p38 MAPK and ERK1/2 phosphorylation in HSCs. Suppression of IL-17RA expression may be a strategy to reduce the inflammatory response induced by IL-17A in the liver.

Effects of anti-viral therapy and HCV clearance on cerebral metabolism and cognition

BACKGROUND & AIMS

Chronic hepatitis C virus (HCV) infection is associated with altered cerebral metabolism and cognitive dysfunction. We aimed to evaluate the effect of pegylated interferon/ribavirin (PIFN/R) and HCV clearance on cerebral metabolism, and neuropsychological performance.

METHODS

Fifteen non-cirrhotic HCV positive subjects underwent (1)H MR spectroscopy (MRS) before, during, and after treatment with PIFN/R. The metabolites of interest namely, N-acetylaspartate (NAA), choline (Cho), myo-inositol (MI), and the control metabolite creatine (Cr), were acquired from 3 different brain regions; left basal ganglia, left frontal cortex, and left dorso-lateral pre-frontal cortex. Coinciding with this, subjects also underwent a battery of neuropsychological tests to evaluate the domains of verbal learning, memory, attention, language, executive functioning, and motor skills. Seven HCV positive controls (not receiving anti-viral therapy) underwent MRS and neuropsychological testing at two time points, 12 weeks apart, to examine for variation in cerebral metabolites over time and the practice effect of repeat neuropsychological testing.

RESULTS

Significant reductions in basal ganglia Cho/Cr (p=0.03) and basal ganglia MI/Cr (p=0.03) were observed in sustained virological responders (SVRs, n=8), but not non-responders/relapsers (NR/R, n=6), indicative of reduced cerebral infection and/or immune activation in those who cleared virus. SVRs demonstrated significant improvements in verbal learning, memory, and visuo-spatial memory. A small but significant improvement in neurocognitive function secondary to the practice effect was seen in both HCV controls and HCV subjects during treatment.

CONCLUSIONS

HCV eradication has a beneficial effect on cerebral metabolism and selective aspects of neurocognitive function and is an important factor when contemplating anti-viral therapy in HCV, especially in those with mild disease.

Hepatitis C virus co-infection increases neurocognitive impairment severity and risk of death in treated HIV/AIDS

Previous studies have reported that hepatitis C virus (HCV) co-infection worsens neurocognitive status among individuals with human immunodeficiency virus (HIV)-1 infection. We assessed the prevalence of neurologic disorders and the severity of HIV-associated neurocognitive impairment among HIV-infected individuals in two centralized HIV clinics in Alberta, Canada from 1998 to 2010 based on their HCV serostatus. Of 456 HIV-infected persons without concurrent substance abuse, 91 (20.0%) were HCV seropositive. Of 58 neurologic disorders identified in the cohort, HIV/HCV co-infected individuals exhibited a higher prevalence of multiple neurologic disorders compared to HIV-infected individuals (60.4% vs. 46.6%, p<0.05) and a higher frequency of seizures (28.6% vs. 17.8%, p<0.05). Unlike HIV mono-infected persons, the risk of seizures was independent of immune status in HIV/HCV co-infected individuals (p<0.05). Symptomatic HIV-associated neurocognitive disorders (sHAND) were more severe among HIV/HCV co-infected persons (p<0.05). HCV co-infection was associated with an increased mortality rate (24.2% vs. 14.5%, p<0.05) with a mortality hazard ratio of 2.38 after adjusting for demographic and clinical variables. Our results indicate that the presence of HCV co-infection among HIV-infected individuals increased neurologic disease burden and risk of death, underscoring HCV's capacity to affect the nervous system and survival of HIV-infected persons.

High baseline interleukine-8 level is an independent risk factor for the achievement of sustained virological response in chronic HCV patients

Hepatitis C virus (HCV), a major cause of liver disease throughout the world, is difficult to treat with interferon (IFN) (and various formulations and combinations thereof) being the only approved molecule available. It has been investigated recently that proinflammatory chemokine interleukin-8 (IL-8) induced by HCV partially inhibits the antiviral IFN-α therapy. Therefore, the current study was aimed to prospectively utilize the baseline IL-8 levels in the HCV infected serum and predicts its role in sustained virological response (SVR) to IFN-α+ribavirin therapy, in chronic HCV patients in Pakistan. One hundred and ten hepatitis C patients without any other infections underwent IFN-α+ribavirin combination treatment. Baseline IL-8 levels were determined before starting of the therapy for all these patients. Fifteen normal volunteers negative for HCV were kept as control. The baseline IL-8 levels were found significantly higher in all HCV positive patients as compared to normal healthy volunteers (1083.54 ± 85.72 pg/ml versus 6.99 ± 1.05 pg/ml [mean ± SEM], p<0.01) and were also significantly higher in non-responders than responders (p<0.05). Comparatively higher mean baseline IL-8 levels were observed in non-responders (2442.02 ± 159.92 pg/ml), than late (1009.31 ± 45.31) and rapid (540.91 ± 27.06 pg/ml) responders. Significant relation was observed between baseline IL-8 level and response to IFN therapy (p<0.01). Results of this study suggest that increased levels of IL-8 in HCV infection might be involved in pathogenesis, persistence and resistance to IFN-α+ribavirin combination therapy.

Analysis of interferon signaling by infectious hepatitis C virus clones with substitutions of core amino acids 70 and 91

Substitution of amino acids 70 and 91 in the hepatitis C virus (HCV) core region is a significant predictor of poor responses to peginterferon-plus-ribavirin therapy, while their molecular mechanisms remain unclear. Here we investigated these differences in the response to alpha interferon (IFN) by using HCV cell culture with R70Q, R70H, and L91M substitutions. IFN treatment of cells transfected or infected with the wild type or the mutant HCV clones showed that the R70Q, R70H, and L91M core mutants were significantly more resistant than the wild type. Among HCV-transfected cells, intracellular HCV RNA levels were significantly higher for the core mutants than for the wild type, while HCV RNA in culture supernatant was significantly lower for these mutants than for the wild type. IFN-induced phosphorylation of STAT1 and STAT2 and expression of the interferon-inducible genes were significantly lower for the core mutants than for the wild type, suggesting cellular unresponsiveness to IFN. The expression level of an interferon signal attenuator, SOCS3, was significantly higher for the R70Q, R70H, and L91M mutants than for the wild type. Interleukin 6 (IL-6), which upregulates SOCS3, was significantly higher for the R70Q, R70H, and L91M mutants than for the wild type, suggesting interferon resistance, possibly through IL-6-induced, SOCS3-mediated suppression of interferon signaling. Expression levels of endoplasmic reticulum (ER) stress proteins were significantly higher in cells transfected with a core mutant than in those transfected with the wild type. In conclusion, HCV R70 and L91 core mutants were resistant to interferon in vitro, and the resistance may be induced by IL-6-induced upregulation of SOCS3. Those mechanisms may explain clinical interferon resistance of HCV core mutants.

Effect of suppressor of cytokine signaling on hepcidin production in hepatitis C virus replicon cells

AIM

  Hepcidin is a key regulator of systemic iron metabolism and its expression is modulated by hepatitis C virus (HCV) infection. Suppressor of cytokine signaling 1 (SOCS-1) and SOCS-3 act as negative regulators of the Jak/signal transducers and activators of transcription signaling pathway. In this study, we investigated how HCV infection modulates SOCS-1 and SOCS-3 production and how these SOCS proteins affect hepcidin production.

METHODS

  The effects of SOCS-1 and SOCS-3 on hepcidin production were investigated using a complete genome, HCV replicon system.

RESULTS

  Unexpectedly, basal expression levels of hepcidin (HAMP) mRNA and the bioactive form of hepcidin protein, hepcidin-25, were significantly higher in replicon cells. Regardless of HCV infection, STAT3 was activated in response to interleukin-6 (IL-6), but this activation was greater in replicon cells than in cured cells. Basal expression of the SOCS-3 protein was enhanced, but basal expression of SOCS-1 protein was reduced, in replicon cells. Expression of SOCS-3 increased dramatically in response to IL-6 stimulation but expression of SOCS-1 was not induced by IL-6. Interestingly, silencing of SOCS-1 and SOCS-3 gene expression enhanced STAT3 activation and HAMP gene expression. In addition, overexpression of SOCS-1 protein strongly suppressed STAT3 activation and HAMP gene expression.

CONCLUSIONS

  This in vitro study shows that SOCS-3 expression was enhanced but SOCS-1 expression was reduced by HCV infection. The upregulation of hepcidin induced by IL-6 was found to be negatively regulated by SOCS-1 and SOCS-3. The modulation of SOCS1 and SOCS3 in HCV-infected hepatocytes may explain, at least in part, the relative shortage of hepcidin production in CH-C.

Chronic pain and hepatitis C virus infection in opioid dependent injection drug users

It is unknown whether infection with hepatitis C is a risk factor for pain among people who have used injection drugs. Multivariate regression was used to determine whether hepatitis C was associated with greater likelihood of reporting significant chronic pain and discomfort intolerance in a cohort of 97 injection drug users dependent on opioids. Study results suggest that participants with hepatitis C may be more likely to experience chronic pain (aOR=1.98; 95% confidence interval=0.76 to 5.12, p=0.16). Furthermore, hepatitis C was found to be associated with a higher discomfort intolerance scale score, reflecting intolerance to physical discomfort (β=2.34; 95% confidence interval=0.06 to 4.62; p=0.04). Hepatitis C may be a cause for chronic pain and discomfort intolerance that is overlooked among injection drug users dependent on opioids.

Plasma Cytokines and Portopulmonary Hypertension in Patients With Cirrhosis Waiting for Orthotopic Liver Transplantation

Portopulmonary hypertension (PPHTN) is a rare complication in patients with portal hypertension. A role of endothelin 1 (ET-1) and other cytokines was demonstrated in primary pulmonary hypertension but not in PPHTN. We evaluated the possible role of ET-1, interleukin 6 (IL-6), interleukin 1β (IL-1β), and tumor necrosis factor alpha (TNF-α) in the pathogenesis of PPHTN. Plasmatic concentrations of ET-1, IL-6, IL-1β, and TNF-α were measured in patients with pulmonary systolic arterial pressure (PAPs) >30 mm Hg and in patients with cirrhosis. In all, Six out of 11 patients with PAPs >30 mm Hg had PPHTN on right heart catheterization. The remaining 10 patients had an hyperdynamic circulation (HC). In PPHTN patients, ET-1 and IL-6 were significantly higher compared with HC and patients with cirrhosis. Endothelin 1 and IL-6 could be implicated in the pathogenesis of PPHTN. On the basis of these results, ET-1 receptor antagonists or anti-IL-6 could have a rationale in the treatment of PPHTN.

Complete blood count, measures of iron status and inflammatory markers in inner-city African Americans with undiagnosed hepatitis C seropositivity

BACKGROUND

Hepatitis C virus (HCV) infection may be associated with thrombocytopenia and increased iron stores in patients receiving medical care. We aimed to determine how often changes in hematologic, iron metabolic and inflammatory markers occur in individuals with undiagnosed HCV in the community.

METHODS

Inner-city African Americans (n=143) were recruited from the community according to reported ingestion of alcohol. They were divided broadly into those who drank more or less than 56 g alcohol/day as assessed by dietary questionnaire. HCV serology was determined and laboratory values were compared according to HCV seropositivity in analyses that adjusted for alcohol consumption.

RESULTS

The prevalence of HCV seropositivity was 23% among men and 29% among women. Levels of hepatocellular enzymes were higher with HCV seropositivity (P<0.0001) but hemoglobin concentrations, white blood cell and platelet counts and serum ferritin concentrations did not differ. The globulin fraction of the serum protein concentration (P=0.002) was increased with HCV seropositivity as expected with chronic inflammation. However, erythrocyte sedimentation rate and serum iron and haptoglobin levels did not differ significantly according to HCV status. Furthermore, multivariate analysis revealed that C-reactive protein was decreased and transferrin concentration was increased with both HCV and alcohol consumption (P<0.014).

CONCLUSIONS

Previously undiagnosed HCV seropositivity has little effect on the complete blood count and body iron stores but appears to perturb the response to an inflammatory stimulus, causing reduced rather than increased circulating CRP concentrations and increased rather than decreased transferrin concentrations.

Steatosis and insulin resistance in hepatitis C: A way out for the virus?

The hepatitis C virus (HCV) induces lipid accumulation in vitro and in vivo. The pathogenesis of steatosis is due to both viral and host factors. Viral steatosis is mostly reported in patients with genotype 3a, whereas metabolic steatosis is often associated with genotype 1 and metabolic syndrome. Several molecular mechanisms responsible for steatosis have been associated with the HCV core protein, which is able to induce gene expression and activity of sterol regulatory element binding protein 1 (SREBP1) and peroxisome proliferator-activated receptor γ (PPARγ), increasing the transcription of genes involved in hepatic fatty acid synthesis. Steatosis has been also implicated in viral replication. In infected cells, HCV core protein is targeted to lipid droplets which serve as intracellular storage organelles. These studies have shown that lipid droplets are essential for virus assembly. Thus, HCV promotes steatosis as an efficient mechanism for stable viral replication. Chronic HCV infection can also induce insulin resistance. In patients with HCV, insulin resistance is more strongly associated with viral load than visceral obesity. HCV seems to lead to insulin resistance through interference of intracellular insulin signalling by HCV proteins, mainly, the serine phosphorylation of insulin receptor-1 (IRS-1) and impairment of the downstream Akt signalling pathway. The HCV core protein interferes with in vitro insulin signalling by genotype-specific mechanisms, where the role of suppressor of cytokine signal 7 (SOCS-7) in genotype 3a and mammalian target of rapamycin (mTOR) in genotype 1 in IRS-1 downregulation play key roles. Steatosis and insulin resistance have been associated with fibrosis progression and a reduced rate of sustained response to peginterferon plus ribavirin.

Advanced periductal fibrosis from infection with the carcinogenic human liver fluke Opisthorchis viverrini correlates with elevated levels of interleukin-6

More than 750 million people are at risk of infection with foodborne liver flukes. Opisthorchis viverrini is considered among the most important of these parasites, due to its strong association with cholangiocarcinoma (CCA). O. viverrini infection results in a chronic inflammatory challenge to the host, which can lead to advanced, pathogen-specific disease sequelae including obstructive jaundice, hepatomegaly, cholecystitis, as well as CCA. However, before disease sequelae are apparent, important inflammatory changes to the liver can be detected early during O. viverrini infection. In a case-control study involving 328 men and women with O. viverrini infection, we determined the presence of advanced periductal fibrosis in asymptomatic, O. viverrini-infected individuals and then measured cytokine responses to O. viverrini excretory/secretory products (ES). In the 200 participants with advanced periductal fibrosis (cases), levels of interleukin-6 (IL-6) to O. viverrini ES were 8 times higher than levels of the 128 O. viverrini-infected individuals without advanced periductal fibrosis (controls). Moreover, elevated IL-6 to parasite ES was associated with increased risk of advanced periductal fibrosis by 63% in a model adjusted for sex and age. The risk of advanced periductal fibrosis was also found to increase with higher levels of IL-6: individuals in the third quartile of IL-6-ES production had a 127% higher risk of developing advanced periductal fibrosis than individuals in the first quartile of IL-6 production. O. viverrini-infected individuals with advanced periductal fibrosis showed other hepatobiliary abnormalities, including reduced gallbladder contractility and the presence of gallbladder sludge.

CONCLUSION

These data strongly implicate a role for parasite-specific IL-6 in the pathogenesis of advanced periductal fibrosis in opisthorchiasis, with possible links to other hepatobiliary abnormalities, including CCA.

Hepatitis C virus infection: molecular pathways to metabolic syndrome

Chronic infection with hepatitis C virus (HCV) can induce insulin resistance (IR) in a genotype-dependent fashion, thus contributing to steatosis, progression of fibrosis and resistance to interferon therapy. The molecular mechanisms in genotype 1 patients that lead to metabolic syndrome are still ambiguous. Based on our current understanding, HCV proteins associate with mitochondria and endoplasmic reticulum and promote oxidative stress. The latter mediates signals involving the p38 mitogen-activated protein kinase and activates nuclear factor kappa B. This transcription factor plays a key role in the expression of cytokines, tumor necrosis factor alpha (TNF-alpha), interleukin 6, interleukin 8, tumor growth factor beta, and Fas ligand. TNF-alpha inhibits the function of insulin receptor substrates and decreases the expression of the glucose transporter and lipoprotein lipase in peripheral tissues, which is responsible for the promotion of insulin resistance. Furthermore, reduced adiponectin levels, loss of adiponectin receptors, and decreased anti-inflammatory peroxisome proliferator-activated receptor alpha in the liver of HCV patients may contribute to reduced fatty acid oxidation, inflammation, and eventually lipotoxicity. This chain of events may be initiated by HCV-associated IR and provides a direction for future research in the areas of therapeutic intervention.

Association of TGF-beta1 codon 25 (G915C) polymorphism with hepatitis C virus infection

Cytokines play a key role in the regulation of immune responses. In hepatitis C virus infection (HCV), the production of abnormal cytokine levels appears to contribute to the progression of the disease, viral persistence, and affects response to therapy. Cytokine genes are polymorphic at specific sites, and certain polymorphisms located within coding/regulatory regions have been shown to affect the overall expression and secretion of cytokines. The aim of the present study was to identify potential markers of cytokines genes associated with the susceptibility to HCV infection. The cohort was composed of 128 individuals infected by HCV and 94 healthy controls. Genotyping was carried out by PCR-SSP. The distributions of the following polymorphisms were compared in these groups: TNF-alpha (-308G/A [rs1800629]), TGF-beta1 (codon 10 T/C [rs1982073], codon 25 G/C [rs1800471]), IL-10 (-1082 A/G [rs 1800896]; -819T/C [rs1800871]; -592A/C [rs 1800872]), IL-6 (-174G/C [rs1800795]), and IFN-gamma (+874T/A [rs2430561]). This study demonstrated a statistically significant difference in the frequency of TGF-beta1 codon 25 polymorphism between healthy subjects and those infected with HCV. No associations were observed between polymorphisms of TNF-alpha, IFN-gamma, IL-10, TGF-beta1 codon 10, and IL-6 and HCV infection. These findings suggest that TGF-beta1 codon 25 polymorphism could be a host genetic factor associated with susceptibility to HCV infection.

Defective response to Toll-like receptor 3 and 4 ligands by activated monocytes in chronic hepatitis C virus infection

Toll-like receptors (TLR) have a critical role in innate immunity against pathogens. We investigated the cytokine response to TLR stimulation in peripheral blood cells of subjects infected with hepatitis C virus (HCV) and/or human immunodeficiency virus (HIV) in the Women Interagency HIV Study (WIHS) cohort. Interleukin (IL)-6 in response to TLR3 and TLR4 ligands such as polyinosinic-polycytidylic acid and lipopolysaccharide was significantly compromised in HCV-infected women. High spontaneous secretion of IL-6 suggested pre-existing cell activation as a factor mediating reduced responses to TLR3 and TLR4 stimulation. To a lesser extent, tumour necrosis factor-alpha and IL-1beta responses to TLR stimulation were also compromised. Monocytes, but not B cells or NK cells, were identified as the cell population spontaneously secreting cytokines and also as the cells responding to TLR stimulation. These results highlight a functional defect in antigen-presenting cells of women with HCV infection or co-infection. In women with existing HIV co-infection, decreased cytokine function of antigen-presenting cells suggests another mechanism contributing to immune dysfunction in addition to the HIV-associated CD4 defect.

[Prevalence of hepatitis C infection in patients with type 2 diabetes mellitus]

BACKGROUND

Recently, a possible epidemiological association between hepatitis C virus infection and diabetes mellitus has been suggested and a higher prevalence of HCV antibodies has been found among type 2 diabetic when compared with normal controls.

AIM

To evaluate the prevalence of hepatitis C infection in diabetic patients in Curitiba, PR, Brazil.

PATIENTS AND METHODS

A total of 145 type 2 and 104 type 1 diabetic patients attending the outpatient diabetic unit of an university hospital were consecutively tested for anti-HCV, using a fourth-generation enzyme-linked immunosorbent assay (ELISA). The control group was constituted by 16,720 volunteer blood donors attending the blood bank of the same hospital during the period of the study. Diabetic patients were also evaluated for clinical, biochemical (aminotransferase levels) and demographic variables and previous exposure to risk factors for hepatitis C infection.

RESULTS

A higher prevalence of hepatitis C infection was observed in type 2 diabetic patients in comparison with blood donors. Although anti-HCV prevalence in type 2 diabetic patients was higher than found in type 1, it did not reach statistical significance. Both diabetic groups were predominantly female, and as expected, type 2 diabetic were older than type 1. Race distribution, duration of the disease, and previous exposure to hepatitis C risk factors were similar in both groups, but type 2 diabetic subjects had higher median levels of alanine aminotransferase than type 1.

CONCLUSIONS

A higher prevalence of hepatitis C infection was detected in type 2 diabetic patients in comparison with blood donors in our region, in accordance with study data from different populations. If all type 2 diabetic patients should undergo regular screening for hepatitis C infection remains a question.

Insulin resistance and liver injury in hepatitis C is not associated with virus-specific changes in adipocytokines

The role of tumor necrosis factor alpha, interleukin 6, leptin, and adiponectin in the pathogenesis of hepatitis C virus (HCV)-associated insulin resistance (IR) remains controversial. We tested the hypothesis that these adipocytokines contribute to chronic HCV-associated IR and liver injury by first comparing their serum levels and homeostasis model assessment of insulin resistance (HOMA-IR) in 154 untreated, non-diabetic, HCV-infected male subjects with fibrosis stage 0-2, to that in 75 healthy volunteers matched for age, body mass index (BMI), and waist-hip ratio (WHR). We next examined whether the adipocytokine levels were associated with the extent of hepatic steatosis, portal/periportal inflammation and fibrosis in our total cohort of 240 HCV-infected male subjects. Significantly higher levels of HOMA-IR (2.12 versus 1.63, P = 0.01), TNFalpha (1.28 versus 0.60 pg/ml, P < 0.001) and IL6 (2.42 versus 1.15 pg/ml, P = 0.001) were noted in the HCV cohort compared with healthy controls respectively, but there were no significant differences in leptin and adiponectin concentrations. By multiple linear regression, independent predictors of HOMA-IR included the body mass index, and the serum levels of leptin (positive correlation) and adiponectin (negative correlation), but not that of TNFalpha and IL6. Only TNFalpha levels were correlated with the extent of histological injury (portal/periportal inflammation, P = 0.02).

CONCLUSION

Whereas leptin and adiponectin contribute to IR, none of the adipocytokines accounted for the elevated IR in HCV-infected subjects. The adipocytokines were not associated with histological features of chronic HCV infection except for TNFalpha which correlated with portal/periportal inflammation. HCV-associated IR is most likely an adipocytokine-independent effect of the virus to modulate insulin sensitivity.

Host immune status and incidence of hepatocellular carcinoma among subjects infected with hepatitis C virus: a nested case-control study in Japan

A nested case-control study was conducted to examine the association between host immune status, as characterized by serum immune marker levels, and the development of hepatocellular carcinoma (HCC) up to 8 years later in persons with chronic hepatitis C virus (HCV) infection. Cases (n = 39) and matched controls (n = 117) were selected from participants of the Town C HCV Study in Japan between 1996 and 2004 and matched on age at first available sample (+/-1 year), gender, and length of follow-up. Separate analyses were done for each of three serum immune markers: soluble tumor necrosis factor-receptor II (sTNF-R2) and soluble intercellular adhesion molecule-1 (sICAM-1), as indicators of type 1, cell-mediated immune response, and soluble CD30 (sCD30), as an indicator of type 2, humoral immune response. The median concentrations of sTNF-R2, sICAM-1, and sCD30 among controls were 3,170 pg/mL, 305 ng/mL, and 3.0 units/mL, respectively, and were higher among cases (3,870 pg/mL, 372 ng/mL, and 3.3 units/mL, respectively). The risk of developing HCC among subjects with immune marker concentrations above the median levels of the controls was >2-fold greater than among subjects with lower concentrations for all three markers [sTNF-R2: odds ratio (OR), 6.9; 95% confidence interval (95% CI), 2.4-20.5; sICAM-1: OR, 2.0; 95% CI, 0.9-4.1; and sCD30: OR, 2.1; 95% CI, 1.0-4.7]. Simultaneous adjustment for all three markers revealed only sTNF-R2 to be associated with HCC risk (OR, 6.4; 95% CI, 2.0-20.6). Adjustment for alcohol consumption and HCV serotype did not materially alter these associations. Results from this prospective, community-based study suggest that a dysregulation in both type 1-related and type 2-related host immunity contributes to the development of HCV-associated HCC.

Markers for sepsis diagnosis: what is useful?

Timely diagnosis of the different severities of septic inflammation is potentially lifesaving because therapies that have been shown to lower mortality should be initiated early. Sepsis and severe sepsis are accompanied by clinical and laboratory signs of systemic inflammation but patients with inflammation caused by noninfectious causes may present with similar signs and symptoms. It is important to identify markers for an early diagnosis of sepsis and organ dysfunction. This article presents currently interesting sepsis biomarkers. Other novel markers and their potential role are discussed.

Hepatitis C inflection in dialysis patients: a link to poor clinical outcome?

Among the 350,000 maintenance dialysis patients in the USA, the mortality rate is high (20-23% per year) as is the prevalence of hepatitis C virus (HCV) infection (5-15%). An additional same number of dialysis patients in the USA may be infected with HCV but have undetectable HCV antibodies. Almost half of all deaths in dialysis patients, including HCV-infected patients, are due to cardiovascular disease. Since over two-thirds of dialysis patients die within 5 years of initiating dialysis and because markers of malnutrition-inflammation complex syndrome (MICS), rather than traditional cardiovascular risk factors, are among the strongest predictors of early death in these patients, the impact of HCV infection on nutritional status and inflammation may be a main cause of poor survival in this population. Based on data from our cross-sectional and limited longitudinal studies, we hypothesize that HCV infection confounds the association between MICS and clinical outcomes in dialysis patients and, by doing so, leads to higher short-term cardiovascular events and death. Understanding the natural history of HCV and its association with inflammation, nutrition and outcomes in dialysis patients may lead to testing more effective anti-HCV management strategies in this and other similar patient populations, providing benefits not only for HCV infection but the detrimental consequences associated with this infection. In this article, we review the link between the HCV infection and mortality in dialysis patients and compare HCV antibody to molecular methods to detect HCV infection in these individuals.

Interleukin-6 and its soluble receptor in patients with liver cirrhosis and hepatocellular carcinoma

AIM

To evaluate the immunohistochemical localization of interleukin-6 (IL-6) and IL-6 receptor (IL-6R) on tumor tissue specimens from patients with hepatocellular carcinoma (HCC) and the serum levels of IL-6 and sIL-6R in a group of patients with HCC as well as liver cirrhosis (LC) in a group of patients with LC alone and in a control group.

METHODS

Three groups of subjects were studied: group I (n = 83) suffering from HCC and LC, group II (n = 72) suffering from LC alone and group III (n = 42) as healthy controls. All patients had hepatitis C virus infection. Serum IL-6 and IL-6R levels were determined using a commercially available ELISA kit. Immunohistochemistry was performed using the streptavidin-biotin complex and rabbit polyclonal antibodies against IL-6 and IL-6R.

RESULTS

Immunohistochemistry analysis showed a medium to strong cytoplasmic and membrane reactivity for IL-6 and IL-6R respectively, in at least 40% of cases of HCC, whereas liver cirrhosis patients and controls were negative for IL-6 or showed a very mild and focal dot-like cytoplasmic reaction for IL-6R. Serum IL-6 levels in HCC group were significantly higher than those in LC and control groups (P < 0.0001). There was no significant difference in sIL-6R concentrations among 3 groups. When the patients with HCC were divided into groups according to Okuda's classification, a significant serum increase of IL-6 and sIL-6R level was observed from stage I to stage III (P < 0.02, P < 0.0005). When HCC and LC patients were divided into 3 classes of cirrhosis severity according to Child-Pugh, values in HCC patients were significantly higher than those in LC patients for each corresponding class (P < 0.01).

CONCLUSION

IL-6 serum levels in HCC patients are higher than those in LC patients and controls, suggesting an increased production of this cytokine by neoplastic cells. sIL-6R values are similar in all groups, increasing only in stage III HCC patients. These data suggest that they have a closer relationship with the neoplastic mass rather than with the residual functioning hepatic mass.

Proinflammatory cytokines, insulin resistance, and insulin secretion in chronic hepatitis C patients: A case-control study

OBJECTIVE

The purpose of this study was to explore the initial pathogenic mechanisms of diabetes associated with hepatitis C virus (HCV) infection.

RESEARCH DESIGN AND METHODS

Insulin resistance, proinflammatory cytokines, and beta-cell function were evaluated in a case-control study. A total of 28 consecutive nondiabetic patients with chronic hepatitis C were included in the study (anti-HCV+). Fourteen patients with chronic hepatitis other than HCV infection served as the control group (anti-HCV-). Both groups were closely matched by the main clinical variables associated with insulin resistance and the degree of liver fibrosis. In addition, there were no differences between groups regarding hepatic insulin extraction measured by calculating the ratio between C-peptide and insulin. Serum levels of proinflammatory cytokines (tumor necrosis factor [TNF]-alpha, soluble TNF receptor [sTNFR] 1, soluble TNFR2, and interleukin-6) were measured by enzyme-linked immunosorbent assay. Insulin resistance (homeostasis model assessment [HOMA] of insulin resistance [HOMA-IR]) and insulin secretion at baseline (HOMA-beta) and after various stimulus (oral glucose tolerance test, standard food intake, and intravenous glucagon) were determined by previously validated mathematic indexes.

RESULTS

HOMA-IR was higher in anti-HCV+ than in anti-HCV- patients (4.35 +/- 2.27 vs. 2.58 +/- 1.74; P = 0.01). All the proinflammatory cytokines analyzed were significantly higher in anti-HCV+ patients than in anti-HCV- patients. In addition, sTNFR1 and sTNFR2 were directly correlated to HOMA-IR. HOMA-beta as well as insulin and C-peptide responses after the intravenous glucagon test were significantly higher in anti-HCV+ patients than in anti-HC- patients.

CONCLUSIONS

Insulin resistance mediated by proinflammatory cytokines, but not a deficit in insulin secretion, could be the primary pathogenic mechanism involved in the development of diabetes associated with HCV infection.

Interleukin-6 and its soluble receptor in patients with liver cirrhosis and hepatocellular carcinoma

AIM: To evaluate the immunohistochemical localization of interleukin-6 (IL-6) and IL-6 receptor (IL-6R) on tumor tissue specimens from patients with hepatocellular carcinoma (HCC) and the serum levels of IL-6 and sIL-6R in a group of patients with HCC as well as liver cirrhosis (LC) in a group of patients with LC alone and in a control group.

METHODS: Three groups of subjects were studied: group I (n = 83) suffering from HCC and LC, group II (n = 72) suffering from LC alone and group III (n = 42) as healthy controls. All patients had hepatitis C virus infection. Serum IL-6 and IL-6R levels were determined using a commercially available ELISA kit. Immunohistochemistry was performed using the streptavidin-biotin complex and rabbit polyclonal antibodies against IL-6 and IL-6R.

RESULTS: Immunohistochemistry analysis showed a medium to strong cytoplasmic and membrane reactivity for IL-6 and IL-6R respectively, in at least 40% of cases of HCC, whereas liver cirrhosis patients and controls were negative for IL-6 or showed a very mild and focal dot-like cytoplasmic reaction for IL-6R. Serum IL-6 levels in HCC group were significantly higher than those in LC and control groups (P < 0.0001). There was no significant difference in sIL-6R concentrations among 3 groups. When the patients with HCC were divided into groups according to Okuda’s classification, a significant serum increase of IL-6 and sIL-6R level was observed from stage I to stage III (P < 0.02, P < 0.0005). When HCC and LC patients were divided into 3 classes of cirrhosis severity according to Child-Pugh, values in HCC patients were significantly higher than those in LC patients for each corresponding class (P < 0.01).

CONCLUSION: IL-6 serum levels in HCC patients are higher than those in LC patients and controls, suggesting an increased production of this cytokine by neoplastic cells. sIL-6R values are similar in all groups, increasing only in stage III HCC patients. These data suggest that they have a closer relationship with the neoplastic mass rather than with the residual functioning hepatic mass.

Serum levels of interleukin-6 and its soluble receptors in patients with hepatitis C virus infection

Interleukin-6 (IL-6) is an important cytokine in liver regeneration, and elevated levels of IL-6 have been demonstrated in patients with chronic liver diseases (CLD). Many biological effects of IL-6 depend on naturally occurring soluble IL-6 receptors. In the present study we measured the concentrations of IL-6 and its soluble receptors in the sera of patients with CLD related to hepatitis C virus (HCV) infection. We studied 77 patients with varying degrees of HCV-related CLD. Serum levels of IL-6 and its soluble receptors (sIL-6R, sgp130) were measured by enzyme-linked immunosorbent assay. Serum IL-6 and sIL-6R were elevated in patients with CLD compared with healthy subjects. Serum levels of sgp130 did not differ between patients with chronic hepatitis and healthy subjects. However, in patients with liver cirrhosis, sgp130 was significantly elevated and was positively correlated with total bilirubin and negatively correlated with cholinesterase and prothrombin time. Our study demonstrated that in patients with HCV-related CLD, serum IL-6 and its soluble receptor levels are correlated with both liver function impairment and the degree of liver fibrosis. These observations suggest that the balance of IL-6 and its soluble receptors may correspond to the state of liver damage in patients with CLD.

Microarray analyses and molecular profiling of Stat3 signaling pathway induced by hepatitis C virus core protein in human hepatocytes

Hepatitis C virus (HCV) infection is a major contributor to the development of end-stage liver disease, including cirrhosis and hepatocellular carcinoma (HCC). We have previously shown that HCV core protein promotes immortalization of primary human hepatocytes. To identify molecular changes involved in core protein-mediated immortalization, we have investigated differential gene expression by microarray analyses in primary human hepatocytes and HCV core gene introduced hepatocytes after senescence (early passage), immortalization (middle passage), and anchor-independent growth (late passage). Out of 33,000 human genes screened, 1918 transcripts were differentially expressed (>2-fold) in immortalized human hepatocytes (IHH) as compared to negative controls. Our analyses provided a molecular portrait of changes in gene expression associated with three distinct stages of hepatocytes after introduction of HCV core gene. Many of the overall changes were involved with important cellular pathways, including cell growth regulation, immune regulation, oxidative stress, and apoptosis. We focused on the Stat3 signaling pathway by further verifying selected genes at the protein level relevant to hepatocyte growth regulation. Our data suggested that the introduction of HCV core protein results in an increase in expression of IL-6, gp130, leptin receptor, and Stat3. Upregulation of these genes in turn may regulate c-myc and cyclin D1, downstream of the Stat3 signaling pathway. Identification of these modulated genes with potential roles may help in the selection of targets for therapies against HCV-mediated liver disease progression.