Evolving epidemiology of hepatitis C virus

Beneficial effects of fucoidan in patients with chronic hepatitis C virus infection

AIM: To evaluate the effects of fucoidan, a complex sulfated polysaccharide extract from marine seaweed, on hepatitis C virus (HCV) RNA load both in vitro and in vivo.

METHODS: HCV-1b replicon-expressing cells were cultured in the presence of fucoidan obtained from Cladosiphon okamuranus Tokida cultivated in Okinawa, Japan, and quantified the level of HCV replication. In an open-label uncontrolled study, 15 patients with chronic hepatitis C, and HCV-related cirrhosis and hepatocellular carcinoma were treated with fucoidan (0.83 g/d) for 12 mo. The clinical symptoms, biochemical tests, and HCV RNA levels were assessed before, during, and after treatment.

RESULTS: Fucoidan dose-dependently inhibited the expression of HCV replicon. At 8-10 mo of treatment with fucoidan, HCV RNA levels were significantly lower relative to the baseline. The same treatment also tended to lower serum alanine aminotransferase levels, and the latter correlated with HCV RNA levels. However, the improved laboratory tests did not translate into significant clinical improvement. Fucoidan had no serious adverse effects.

CONCLUSION: Our findings suggest that fucoidan is safe and useful in the treatment of patients with HCV-related chronic liver diseases. Further controlled clinical trials are needed to confirm the present findings.

Viral targets of acylguanidines

Acylguanidines are a new class of antiviral compounds with the unique ability to target both RNA polymerase and transmembrane proteins of viruses from different families. Importantly, they inhibit proteins which are not targeted by existing antiviral therapies, for example, Vpu of HIV type 1, p7 of hepatitis C virus, E of severe acute respiratory syndrome coronavirus and RNA-dependent RNA polymerase of coxsackievirus B3. BIT225, developed by Biotron Limited, is the first acylguanidine in clinical trials against HIV type 1 and hepatitis C virus. In this article we focus on the mechanisms of inhibition of viral proteins by acylguanidines.

Cost-effectiveness and population outcomes of general population screening for hepatitis C

BACKGROUND

Current US guidelines recommend limiting hepatitis C virus (HCV) screening to high-risk individuals, and 50%-75% of infected persons remain unaware of their status.

METHODS

To estimate the cost-effectiveness and population-level impact of adding one-time HCV screening of US population aged 20-69 years to current guidelines, we developed a decision analytic model for the screening intervention and Markov model with annual transitions to estimate natural history. Subanalyses included protease inhibitor therapy and screening those at highest risk of infection (birth year 1945-1965). We relied on published literature and took a lifetime, societal perspective.

RESULTS

Compared to current guidelines, incremental cost per quality-adjusted life year gained (ICER) was $7900 for general population screening and $4200 for screening by birth year, which dominated general population screening if cost, clinician uptake, and median age of diagnoses were assumed equivalent. General population screening remained cost-effective in all one-way sensitivity analyses, 30 000 Monte Carlo simulations, and scenarios in which background mortality was doubled, all genotype 1 patients were treated with protease inhibitors, and most parameters were set unfavorable to increased screening. ICER was lowest if screening was applied to a population with liver fibrosis similar to 2010 estimates. Approximately 1% of liver-related deaths would be averted per 15% of the general population screened; the impact would be greater with improved referral, treatment uptake, and cure.

CONCLUSIONS

Broader screening for HCV would likely be cost-effective, but significantly reducing HCV-related morbidity and mortality would also require improved rates of referral, treatment, and cure.

Recombinant human interleukin 28B: anti-HCV potency, receptor usage and restricted cell-type responsiveness

OBJECTIVES

Interleukin 28B (IL28B) genetic variation has been recently reported as a potent predictor of hepatitis C virus (HCV) response to interferon (IFN) therapy. The aim of this study was to produce recombinant human IL28B (rhIL28B) in yeast and explore the action mechanisms of rhIL28B as a novel anti-HCV agent.

METHODS

A simple and efficient protocol for producing rhIL28B in the methylotrophic yeast Pichia pastoris was developed. The anti-HCV activity, induction of IFN-stimulated genes (ISGs), receptor usage and cellular responsiveness of rhIL28B were characterized.

RESULTS

The yield of secreted rhIL28B was optimized to 200 mg/L, and soluble rhIL28B that was approximately 95% pure was achieved using a one-step ion-exchange purification procedure. rhIL28B inhibited HCV propagation in Huh7.5.1 cells with an IC(50) of 0.15 × 10(-3) mg/L. Treatment of hepatoma cells with rhIL28B resulted in the phosphorylation of STAT1 within 1 h and expression of ISGs. The HCV inhibitory effects of rhIL28B were antagonized by the antibody neutralization of receptors IL10R2 and IL28R1. The combination of rhIL28B and ribavirin synergistically inhibited HCV production in cell culture. Importantly, compared with the broad-spectrum activity of IFN-α, we demonstrated restricted cell-type responsiveness of rhIL28B in liver, lung and prostate cells.

CONCLUSIONS

This study established an easy and highly efficient approach for the production of rhIL28B with potent in vitro antiviral activity and restricted cell tropism, and thus provides a novel antiviral candidate for improving the treatment of HCV-infected patients.

Strongyloides, dengue fever, and tuberculosis conversions in New Zealand police deploying overseas

BACKGROUND

Members of New Zealand Police (NZP) deploy overseas in a variety of roles. There is limited published data on travel-related morbidity in police as a subgroup of travelers.

METHODS

An audit of pre- and postdeployment medical files for all NZP personnel deploying overseas during 2004 to 2010 was undertaken. Of all deployments, 58.9% were within Oceania.

RESULTS

Positive Strongyloides stercoralis serology was returned in 6.07% (95% CI: 3.80%-9.13%) at a rate of 9.00/1,000 person deployment months (pdm) (95% CI: 5.57-13.8). Dengue fever seroconversion was recorded in 4.91% (95% CI: 3.40%-6.83%) at a rate of 8.57/1,000 pdm (95% CI: 5.90-12.0). The relative risk of dengue infection was 7.47 for Timor Leste compared to all other deployment destinations. An association between seroconverting for both dengue fever and Strongyloides was found. Tuberculosis conversion was recorded in 1.76% (95% CI: 0.85%-3.21%) at a rate of 2.92/1,000 pmd (95% CI: 1.48-5.375). A single case of human immunodeficiency virus (HIV) seroconversion was recorded. There were no recorded hepatitis C seroconversions.

CONCLUSIONS

Police deploying overseas appear to have similar rates of dengue and tuberculosis conversion as other groups of travelers, and they appear to be at low risk of hepatitis C and HIV. Strongyloidiasis appears to be a significant risk; postdeployment prevalence was markedly higher than that reported in a small number of studies.

Bile acids specifically increase hepatitis C virus RNA-replication

Background

Hepatitis C virus (HCV) patients with high serum levels of bile acids (BAs) respond poorly to IFN therapy. BAs have been shown to increase RNA-replication of genotype 1 but not genotype 2a replicons. Since BAs modulate lipid metabolism including lipoprotein secretion and as HCV depends on lipids and lipoproteins during RNA-replication, virus production and cell entry, BAs may affect multiple steps of the HCV life cycle. Therefore, we analyzed the influence of BAs on individual steps of virus replication.

Methods

We measured replication of subgenomic genotype (GT) 1b and 2a RNAs as well as full-length GT2a genomes in the presence of BAs using quantitative RT-PCR and luciferase assays. Cell entry was determined using HCV pseudoparticles (HCVpp). Virus assembly and release were quantified using a core-specific ELISA. Replicon chimeras were employed to characterize genotype-specific modulation of HCV by BAs. Lunet CD81/GFP-NLS-MAVS cells were used to determine infection of Con1 particles.

Results

BAs increased RNA-replication of GT1b replicons up to 10-fold but had no effect on subgenomic GT2a replicons both in Huh-7 and HuH6 cells. They did not increase viral RNA translation, virus assembly and release or cell entry. Lowering replication efficiency of GT2a replicons rendered them susceptible to stimulation by BAs. Moreover, replication of full length GT1b with or without replication enhancing mutations and GT2a genomes were also stimulated by BAs.

Conclusions

Bile acids specifically enhance RNA-replication. This is not limited to GT1, but also holds true for GT2a full length genomes and subgenomic replicons with low replication capacity. The increase of HCV replication by BAs may influence the efficacy of antiviral treatment in vivo and may improve replication of primary HCV genomes in cell culture.

Treatment of hepatitis C virus infection in adults and children: updated Swedish consensus recommendations

Swedish recommendations for the treatment of hepatitis C virus (HCV) infection were updated at a recent expert meeting. Therapy for acute HCV infection should be initiated if spontaneous resolution does not occur within 12 weeks. The recommended standard-of-care therapy for chronic HCV genotype 1 infection is an HCV protease inhibitor in combination with peginterferon (peg-IFN) and ribavirin. Treatment is strongly recommended in patients with bridging fibrosis and cirrhosis, whereas in patients with less advanced fibrosis, deferring therapy may be preferential in light of likely therapeutic improvements in the near future. Patients with chronic genotype 2/3 infection should generally be treated with peg-IFN and ribavirin for 24 weeks. In patients with a very rapid viral response (i.e. HCV RNA below 1000 IU/ml on day 7), or favourable baseline characteristics and undetectable HCV RNA week 4, treatment can be shortened to 12-16 weeks, provided that no dose reductions are needed.

Recent Advances in Development of DNA Vaccines Against Hepatitis C virus

Hepatitis C is one of the foremost challenging diseases all over the world. No vaccine has been developed, yet against Hepatitis C virus (HCV). This is partly due to the high mutation rate in the HCV genome, which generates new genotypes and sub genotypes. A mass of efforts have been devoted for the development of an efficient vaccine against HCV. DNA Vaccines, an emerging field of Vaccinology, grasp strong potential to be the most reliable and efficient mode of vaccination in the future. This technology is under investigation currently. Incredibly diverse approaches have been applied as an endeavor to develop a potent DNA vaccine against HCV. The HCV structural genes and the virus like particles have been attempted and so far the results are quite promising in the Lab animals. As there is no proper animal model for HCV infection except chimpanzees, it is very difficult to articulate whether these vaccines will also be pertinent in humans or not. This review will focus on different approaches being used for the development of DNA vaccines, the major tribulations in designing a DNA vaccine against HCV as well as the future prospects for the improvement of under trials DNA vaccines developed against HCV.

Direct binding of a hepatitis C virus inhibitor to the viral capsid protein

Over 130 million people are infected chronically with hepatitis C virus (HCV), which, together with HBV, is the leading cause of liver disease. Novel small molecule inhibitors of Hepatitis C virus (HCV) are needed to complement or replace current treatments based on pegylated interferon and ribavirin, which are only partially successful and plagued with side-effects. Assembly of the virion is initiated by the oligomerization of core, the capsid protein, followed by the interaction with NS5A and other HCV proteins. By screening for inhibitors of core dimerization, we previously discovered peptides and drug-like compounds that disrupt interactions between core and other HCV proteins, NS3 and NS5A, and block HCV production. Here we report that a biotinylated derivative of SL209, a prototype small molecule inhibitor of core dimerization (IC₅₀ of 2.80 µM) that inhibits HCV production with an EC₅₀ of 3.20 µM, is capable of penetrating HCV-infected cells and tracking with core. Interaction between the inhibitors, core and other viral proteins was demonstrated by SL209–mediated affinity-isolation of HCV proteins from lysates of infected cells, or of the corresponding recombinant HCV proteins. SL209-like inhibitors of HCV core may form the basis of novel treatments of Hepatitis C in combination with other target-specific HCV drugs such as inhibitors of the NS3 protease, the NS5B polymerase, or the NS5A regulatory protein. More generally, our work supports the hypothesis that inhibitors of viral capsid formation might constitute a new class of potent antiviral agents, as was recently also shown for HIV capsid inhibitors.

Synthesis and biological activity of bimorpholine and its carbanucleoside

A new enantiomerically pure carbacyclic nucleoside analogue with bimorpholine as a nonaromatic nucleobase was synthesized. The nucleoside analogue and bimorpholine were tested for cytotoxicity using an MTT assay and the xCELLigence System. Both assays revealed that compound 3 was highly cytotoxic at a 50 μM concentration while the cytotoxic effect of compound 1 was much less prominent. No antiretroviral activity was detected for this compound. In contrast, it acted as a potent inhibitor of hepatitis C virus (HCV) replication. Most likely this effect originates largely from the cytotoxicity of the compound; however, it is possible that a specific mechanism of HCV inhibition also exists.

Recruitment and interaction of human dendritic and T cells in autologous liver slices experimentally infected with HCV produced in cell culture

Studying the immunological processes taking place during the initial steps of acute hepatitis C virus (HCV) infection has been a challenge in patients. Shin et al. have recently reported that delayed induction, not impaired recruitment of specific CD8(+) T cells, causes the late onset of acute hepatitis C in chimpanzees (Gastroenterology, 2011). However, further elucidation of the underlying mechanisms is difficult in vivo. We made observations consistent with their conclusions in human liver slices inoculated ex vivo with HCV produced in cell culture (HCVcc). Autologous immune cells were purified from blood and differentially stained prior to their incubation with the slices for 2 hours. A two-photon confocal microscopic analysis revealed that many more stained dendritic and T cells contracted interactions within two-day infected slices than non-inoculated ones (p<0.001). While in the first instance some dendritic and T cells entered into closer interactions, they never did in the latter case. These results suggest that ex vivo infection of human liver slices with HCVcc may be useful for gaining experimental insight regarding the immunological processes taking place at early steps of HCV infections.

Update on alisporivir in treatment of viral hepatitis C

INTRODUCTION

There are two classes of anti-hepatitis C virus (HCV) agents currently in development: direct-acting antivirals (DAA) and host-targeting antivirals (HTA). Cyclophilin inhibitor alisporivir (ALV) , previously known as Debio-025 is the most advanced HTA in development.

AREAS COVERED

Experimental and clinical studies demonstrated that ALV has high genetic barrier and no cross-resistance to DAA. Pharmacokinetic studies showed a profile suitable for once-daily administration. Phase I and II studies confirmed strong HCV suppression and that addition of ALV to pegylated IFNα (PegIFNα) and ribavirin (RBV) can improve their efficacy significantly. ALV was well tolerated and prevalence of the most frequent clinical and laboratory adverse events was similar to PegIFNα/RBV. Hyperbilirubinemia was the only significant adverse event related to ALV, but it was transient, reversible and not associated with hepatotoxicity or cholestasis.

EXPERT OPINION

ALV is pangenotypic, with once-daily administration and safe, therefore medication can be easy and flexible. There is still a need of data in difficult-to-treat populations and genetic studies allowing selection of possible non-responders. Registration of ALV for IFN-based treatment is expected within 3 years, but ALV is also a good candidate for IFN-sparing combinations with DAA.

Management of HIV and hepatitis C virus infections in resource-limited settings

PURPOSE OF REVIEW

To provide an update on the epidemiology and management of HIV and hepatitis C virus (HCV) in resource-limited settings (RLSs).

RECENT FINDINGS

The global prevalence of HIV is 33.3 million people of whom 22.5 million live in sub-Saharan Africa. Hepatitis C affects 170 million people globally with majority of the infected persons living in sub-Saharan Africa and other RLSs. Transmission of these viruses varies greatly even within the RLSs. In the RLSs in Europe, Asia and Central/South America, most transmissions occur through injection drug use, whereas in Africa use of needles for medical treatment and blood transfusion may be the main modes of transmission. However, generally there is a rise in injection drug use even in RLSs.

SUMMARY

Hepatitis C and HIV are common infections and are more prevalent in RLSs, but there are regional differences in transmission even in RLSs. Treatment is difficult in some of the RLSs and prevention by screening donor blood as well and use of sterile instruments in treatment of patients will be important in curbing transmission in some of these settings.

Identification of hepatitis C virus transmission using a next-generation sequencing approach

Here, we describe a transmission event of hepatitis C virus (HCV) among injection drug users. Next-generation sequencing (NGS) was used to assess the intrahost viral genetic variation. Deep amplicon sequencing of HCV hypervariable region 1 allowed for a detailed analysis of the structure of the viral population. Establishment of the genetic relatedness between cases was accomplished by phylogenetic analysis. NGS is a powerful tool with applications in molecular epidemiology studies and outbreak investigations.

Analysis of hepatitis C virus intrahost diversity across the coding region by ultradeep pyrosequencing

Hepatitis C virus (HCV) is the leading cause of liver disease worldwide. In this study, we analyzed four treatment-naïve patients infected with subtype 1a and performed Roche/454 pyrosequencing across the coding region. We report the presence of low-level drug resistance mutations that would most likely have been missed using conventional sequencing methods. The approach described here is broadly applicable to studies of viral diversity and could help to improve the efficacy of direct-acting antiviral agents (DAA) in the treatment of HCV-infected patients.

A compartmentalization model of hepatitis C virus replication: an appropriate distribution of HCV RNA for the effective replication

Hepatitis C virus (HCV) infection is a major cause of liver disease. Ten to twenty percent of chronic hepatitis C will develop complications of chronic liver diseases such as liver cirrhosis and hepatocellular carcinoma. The culture system of HCV is established by the specific combination between HCV strain and a host cell. Some chimeras substituting core to NS2 into the analogous region of JFH1 strain fail to effectively replicate. Core to NS2 of HCV gene mainly encodes the structural protein of HCV virion and contributes to the virion assembly, while other regions mainly contribute to the genome replication. The balance between the virion assembly and the genome replication of chimera may differ from that of reference strain. We construct a mathematical model of the whole replication process of HCV in single infected cell. It is revealed by this model that there are two replication patterns of HCV, explosive and arrested replication. In the explosive replication, HCV can continue to exponentially reproduce its progeny. The explosive replication is caused by the effect of the positive feedback in the replication cycle. On the other hand, in the arrested replication, the replication is stalled after sufficiently long time has passed from the infection because of the depletion of the genome RNA of HCV. To avoid the arrest of replication, HCV RNA must be appropriately distributed to three distinct functions as a template for the genome replication, as a template for the translation of viral proteins and as a component of the viral particle. When the genome replication and the translation of viral proteins precede to the virion assembly, HCV can effectively replicate by explosive replication. It is suggested that some chimeras of HCV fail to effectively replicate because of the inappropriate distribution of HCV RNA to these functions.

Immunosuppression, liver injury and post-transplant HCV recurrence

Hepatitis C virus (HCV) infection is a major cause for liver transplantation worldwide. Still, HCV re-infection of the graft occurs in almost all cases. Most liver transplant recipients experience episodes of graft hepatitis associated with fibrosis progression and graft failure. Clinical management of graft hepatitis can be challenging as in addition to rejection and HCV-induced hepatitis various other factors might be involved including toxic liver injury, steatohepatitis, ischaemic bile duct lesions or infections with other pathogens. Treatment options are often contradictory for different causes of graft hepatitis, and the role of distinct immunosuppressive drugs has been discussed controversially. Corticosteroids increase the infectivity of HCV by altering expression levels of entry factors and other immunosuppressive agents may have diverse effects on HCV replication and fibrosis progression. Interferon alpha-therapy of hepatitis C shows limited efficacy and tolerability in liver transplant recipients and may also cause rejection. In this review we summarize the current knowledge on mechanisms of liver injury in post-transplant hepatitis C, discuss the pros and cons of immunosuppressive agents in this specific setting and describe potential novel approaches to prevent HCV reinfection.

Hepatic STAT1-nuclear translocation and interleukin 28B polymorphisms predict treatment outcomes in hepatitis C virus genotype 1-infected patients

BACKGROUND

We investigated associations between signal transducer and activator of transcription (STAT) 1 in pretreated liver tissues, interleukin (IL) 28B polymorphism and treatment response in hepatitis C virus (HCV)-infected patients treated with peginterferon and ribavirin.

METHODS AND FINDINGS

We performed immunostaining analysis of STAT1 in liver tissues and determined IL28B polymorphism at rs8099917. We then compared the results with treatment outcomes in HCV genotype 1 patients with high viral load who were receiving peginterferon plus ribavirin. In univariate analysis, younger age, white blood cell counts, virological responder, early virological responder (EVR), mild activity (A1) of liver inflammation grading, and lower STAT1 nuclear-stain of hepatocytes in zone 1, zone 2 and total zones of liver were associated with sustained virological responder (SVR). Multivariate analysis showed that EVR, age and hepatic STAT1 nuclear-stain in zone 2 of liver were independent predictors of SVR. It was also revealed that IL28B and STAT1-nuclear translocation in hepatocytes are independent predictors of response to treatment with peginterferon and ribavirin in chronic hepatitis C patients.

CONCLUSIONS

Concomitant assessment of lower STAT1 nuclear-stain of hepatocytes and IL28B polymorphism is useful for prediction of SVR in HCV genotype 1 patients.

Nanomedicine as an emerging approach against intracellular pathogens

Diseases such as tuberculosis, hepatitis, and HIV/AIDS are caused by intracellular pathogens and are a major burden to the global medical community. Conventional treatments for these diseases typically consist of long-term therapy with a combination of drugs, which may lead to side effects and contribute to low patient compliance. The pathogens reside within intracellular compartments of the cell, which provide additional barriers to effective treatment. Therefore, there is a need for improved and more effective therapies for such intracellular diseases. This review will summarize, for the first time, the intracellular compartments in which pathogens can reside and discuss how nanomedicine has the potential to improve intracellular disease therapy by offering properties such as targeting, sustained drug release, and drug delivery to the pathogen’s intracellular location. The characteristics of nanomedicine may prove advantageous in developing improved or alternative therapies for intracellular diseases.

Excess liver-related morbidity of chronic hepatitis C patients, who achieve a sustained viral response, and are discharged from care

Our objective was to address two shortfalls in the hepatitis C virus (HCV) literature: (1) Few data exist comparing post-treatment liver-related mortality/morbidity in HCV-sustained virologic response (SVR) patients to non-SVR patients and (2) no data exist examining liver-related morbidity among treatment response subgroups,particularly among noncirrhotic SVR patients, a group who in the main are discharged from care without further follow-up. A retrospective cohort of 1,215 previously naïve HCV interferon patients (treated 1996-2007)was derived using HCV clinical databases from nine Scottish clinics. Patients were followed up post-treatment for a mean of 5.3 years. (1) By Cox-regression, liver-related hospital episodes (adjusted hazard ratio [AHR]:0.22; 95% confidence interval [CI]: 0.15-0.34) and liver-related mortality [corrected] (AHR: 0.22; 95% CI: 0.09-0.58)were significantly lower in SVR patients, compared to non-SVR patients. (2) Rates of liver-related hospitalization were elevated among all treatment subgroups compared to the general population: Among noncirrhotic SVR patients, adjusted standardized morbidity ratio (SMBR) up to 5.9 (95% CI: 4.5-8.0); among all SVR patients,SMBR up to 10.5 (95% CI: 8.7-12.9); and among non-SVR patients, SMBR up to 53.2 (95% CI: 49.4-57.2).Considerable elevation was also noted among patients who have spontaneously resolved their HCV infection(a control group used to gauge the extent to which lifestyle factors, and not chronic HCV, can contribute toliver-related morbidity), SMBR up to 26.8 (95% CI: 25.3-28.3).

CONCLUSIONS

(1) Patients achieving an SVR were more than four times less likely to be hospitalized, or die for a liver-related reason, than non-SVR patients and (2) although discharged, noncirrhotic SVR patients harbor a disproportionate burden of liver-related morbidity; up to six times that of the general population. Further, alarming levels of liver-related morbidity in spontaneous resolvers is an important finding warranting further study..

Advances in hepatitis C virus vaccines, Part one: Advances in basic knowledge for hepatitis C virus vaccine design

INTRODUCTION

Around 3% of the world population is infected with HCV, with 3 - 4 million newly infected subjects added to this reservoir every year. At least 10% of these people will develop liver cirrhosis or cancer over time, while no approved vaccine against HCV infection is available to date.

AREAS COVERED

This paper includes a detailed and correlated patent (selected by HCAPLUS search database) and literature (searched by PubMed) review on the HCV genome, proteins and key epitopes (including underestimated HCV proteins, alternate reading frame proteins), HCV immunology, immunosuppressive mechanisms and protective correlations of immunity in acute and chronic states of infection (features for prophylactic and therapeutic HCV vaccine design), recent HCV cell culture systems (HCV/JFH1) and animal models. In part two of this review, advances in HCV vaccine formulations and modalities as well as a detailed list of the current trials for HCV vaccine and discussion of the pros and cones of different strategies will be provided.

EXPERT OPINION

By using the advanced basic knowledge and tools obtained about HCV vaccinology in recent years and the application of novel formulations and modalities, at least partially effective vaccines will become available in the near future to prevent (or treat) the chronic (if not the acute) state of HCV infection. A few of such vaccines are already in clinical trials.

Resistance analysis and characterization of a thiazole analogue, BP008, as a potent hepatitis C virus NS5A inhibitor

Hepatitis C virus (HCV) is a global health problem, affecting approximately 3% of the world's population. The standard treatment for HCV infection is often poorly tolerated and ineffective. Therefore, the development of novel or more effective treatment strategies to treat chronic HCV infection is urgently needed. In this report, BP008, a potent small-molecule inhibitor of HCV replication, was developed from a class of compounds with thiazol core structures by means of utilizing a cell-based HCV replicon system. The compound reduced the reporter expression of the HCV1b replicon with a 50% effective concentration (EC(50)) and selective index value of 4.1 ± 0.7 nM and >12,195, respectively. Sequencing analyses of several individual clones derived from BP008-resistant RNAs purified from cells harboring HCV1b replicon revealed that amino acid substitutions mainly within the N-terminal region (domain I) of NS5A were associated with decreased inhibitor susceptibility. Q24L, P58S, and Y93H are the key substitutions for resistance selection; F149L and V153M play the compensatory role in the replication and drug resistance processes. Moreover, BP008 displayed synergistic effects with alpha interferon (IFN-α), NS3 protease inhibitor, and NS5B polymerase inhibitor, as well as good oral bioavailability in SD rats and favorable exposure in rat liver. In summary, our results pointed to an effective small-molecule inhibitor, BP008, that potentially targets HCV NS5A. BP008 can be considered a part of a more effective therapeutic strategy for HCV in the future.

Cytokeratins in hepatitis

Experimental and clinical evidence suggests that cytokeratins (CK), among other physiological functions, are expressed in hepatocytes and can be released in the bloodstream after acute or chronic inflammatory liver injury. Interest in CK in viral and nonviral hepatitis has been rapidly increasing during the last years, especially as they have been proposed as circulating biomarkers of hepatocyte necrosis and apoptosis. In the present review, we sought to summarize and discuss the alterations in circulating CK levels in different form viral and nonviral hepatitis, as well as their potential relation with liver histology. Understanding the mechanisms of hepatitis impact on CK and vice versa is a promising area of research that will positively enhance our understanding of the complexity of acute and chronic inflammatory liver injury.

Current understanding of insulin resistance in hepatitis C

Important breakthroughs have been made in recent years into understanding the close interaction between hepatitis C virus (HCV) infection and glucose homeostasis. Both cross-sectional and longitudinal studies have demonstrated that infection with HCV is associated with an increased risk of developing insulin resistance and Type 2 diabetes. A direct effect of HCV on hepatocyte insulin signaling has been shown in experimental models. Some preliminary observations seem to suggest that indirect mechanisms involving extrahepatic organs might also play a role. The interaction between HCV and glucose metabolism has significant clinical consequences. Insulin resistance and Type 2 diabetes not only accelerate the histological and clinical progression of chronic hepatitis C, but also reduce the virological response to IFN-α-based therapy. Thus, understanding the mechanisms underlying HCV-associated glucose metabolism derangements is of paramount interest in order to improve the clinical management of chronic hepatitis C. This article will focus on the studies that consistently argue in favor of an interrelation between HCV and insulin resistance and will highlight the latest discoveries in this field.