The impact of obesity and metabolic syndrome on chronic hepatitis C

Hepatocellular carcinoma and hepatitis C virus treatments: The bold and the beautiful

The occurrence of hepatocellular carcinoma (HCC) is one of the most serious complications of hepatitis C virus (HCV) infection. Recently, effective antiviral medications have made sustained viral response (SVR) or cure a realistic therapeutic goal for most chronic HCV patients. Given HCV's tumorigenic propensity, it is not surprising that achieving SVR is helpful in preventing HCC. This review briefly summarizes and discusses the existing evidence on the relationship between hepatic carcinogenesis and viral eradication by antivirals, which is mainly divided into interferon-based and direct-acting antivirals (DAAs) based therapy. DAAs have changed the treatment landscape of chronic HCV, reaching high rates of SVR even in patients with advanced cirrhosis, with few contraindications and little side effects. Although some early reports suggested that DAA treatment increased the chance of HCC occurrence, more subsequent observational studies have refuted this theory. The probability of HCC recurrence after HCV eradication appears to be decreasing over time following SVR. Despite virological suppression/cure, individuals with liver cirrhosis are still at risk of HCC and should be monitored. There is a considerable need for markers/scores to predict the long-term risk of HCC in patients with HCV-related liver disease who attain SVR with direct-acting antivirals.

Prevalence and predictors of abnormal alanine aminotransferase in patients with HCV who have achieved SVR

Chronic hepatitis C virus (HCV) is common. Treatment with direct acting antivirals (DAA) result in high sustained virologic response (SVR) associated with normalization of alanine aminotransferase (ALT). However, abnormal ALT after SVR has been observed. Since fatty liver disease can co-exist with HCV, its impact on abnormal ALT after SVR is unknown. This was a retrospective case-control analysis evaluating those with SVR and baseline fatty liver disease by transient elastography defined by controlled attenuated parameter (CAP) was performed. Abnormal ALT was defined as >1.5 ULN. The primary analysis compared abnormal ALT at SVR-12 and beyond in those with and without fatty liver disease. Six-hundred and ninety-three patients with SVR-12 were evaluated. Abnormal ALT at SVR-12 was present in 8.2% and was similar in those with and without fatty liver disease. Abnormal ALT at SVR-12 was associated with atrial fibrillation (p = .02), CAP (p = .047), age (p = .08), baseline ALT (p = .008), BMI (p = .002) and obesity (p = .02). On multivariate analysis, only BMI was associated with abnormal ALT at SVR-12 (p = .017). ALT at follow-up after SVR-12 was available in 264 patients. In those with initial normal ALT (n = 244), 11.5% had a delayed abnormal ALT and in those with initial abnormal ALT (n = 20), 47% remained abnormal while 53% normalized. Abnormal ALT after SVR following treatment with DAA is uncommon and related to increased BMI, but not related to underlying fatty liver disease assessed by CAP. The pattern of ALT can vary, and long-term follow-up is needed to assess the clinical impact of abnormal ALT after SVR.

The Hidden Epidemic: The Prevalence and Impact of Concurrent Liver Diseases in Patients Undergoing Liver Transplantation in Australia and New Zealand

Prevalence of concurrent liver diseases among liver transplant recipients and impact on posttransplant outcomes are unknown.

Methods

This retrospective study included adult liver transplants between January 1' 1985' and December 31' 2019' from the Australian and New Zealand Liver and Intestinal Transplant Registry. Up to 4 liver disease causes were recorded for each transplant; concurrent liver diseases were defined as >1 liver disease indication for transplantation, excluding hepatocellular carcinoma. Impact on posttransplant survival was determined using Cox regression.

Results

A total of 840 (15%) of 5101 adult liver transplant recipients had concurrent liver diseases. Recipients with concurrent liver diseases were more likely male (78% versus 64%) and older (mean age 52 versus 50 y). A higher proportion of liver transplants for hepatitis B (12% versus 6%), hepatitis C (33% versus 20%), alcohol liver disease (23% versus 13%), and metabolic-associated fatty liver disease (11% versus 8%, all P < 0.001) were identified when all indications were included than with primary diagnosis only. The number and proportion of liver transplants performed for concurrent liver diseases have increased from 8 (6%) during Era 1 (1985-1989) to 302 (20%) during Era 7 (2015-2019; P < 0.001). Concurrent liver diseases were not associated with increased posttransplant mortality (adjusted hazard ratio, 0.98, 95% confidence interval, 0.84-1.14).

Conclusions

Concurrent liver diseases are increasing among adult liver transplant recipients in Australia and New Zealand; however, they do not appear to impact posttransplant survival. Reporting all liver disease causes in the transplant registry reports provides more accurate estimates of liver disease burden.

Adolescent Hepatitis C: Prevalence, Impact, and Management Challenges

The prevalence of Hepatitis C virus infection (HCV), a leading cause of chronic liver disease worldwide, is rising in the United States (US) and other high-income countries, especially among youth and young adults. This surge in cases is closely associated with the opioid crisis and intravenous drug use (IVDU). However, its prevalence and impact on the adolescent population have not been thoroughly studied and therefore is poorly understood. The pediatric population tends to have milder liver disease and progression when compared to adults; however, there is a risk of developing liver cirrhosis, in addition to facing decreased quality of life and stigmatization from the disease. The recent approval of direct-acting antiviral (DAA) regimens for all HCV genotypes and age greater than 3 years has revolutionized its management. Therapy has shifted from the prolonged interferon-based regimens, to shorter duration, once daily oral pills that are highly effective, curative and with fewer side effects. Therapy is now indicated for all adolescents with hepatitis C virus infection, regardless of stage of liver disease, recent IVDU, or coinfection with HIV, therefore eliminating a lifetime risk of chronic liver disease, cirrhosis and hepatocarcinoma. Nonetheless, adolescents are rarely tested or treated for hepatitis C infection, and very few adolescents complete therapy. Implementation of point of care (POC) testing of high-risk youth at drug treatment centers or other juvenile facilities may be a good strategy to increase testing, diagnosis and therapy. This review article aims to educate pediatricians and other primary care providers to help decrease the existing knowledge gap on the subject.

Eradication of hepatitis C virus with direct-acting antivirals improves glycemic control in diabetes: A multicenter study

Background and Aim

Hepatitis C virus (HCV) infection causes insulin resistance and diabetes as extrahepatic manifestations. We aimed to analyze the effect of HCV eradication by direct‐acting antiviral (DAA) agents on glucose tolerance.

Methods

The hemoglobin A1c (HbA1c) of 272 patients with HCV infection who achieved a sustained virologic response (SVR) was analyzed at baseline before DAA treatment, at the end of DAA therapy (ETR), and 12 weeks after therapy (Post12W).

Results

There were no significant differences in HbA1c between baseline, ETR, and Post12W in the overall patients. When the data were stratified according to the presence or absence of diabetes, median HbA1c significantly decreased from baseline (7.2%) to ETR (6.8%) and Post12W (6.8%) in the 55 patients with diabetes, whereas there were no significant changes in the patients without diabetes. Basal HbA1c, fasting plasma glucose, and age were independently associated with the changes in HbA1c according to multivariate analysis, and the predictive formula for changes in HbA1c was found to be ΔHbA1c (%) = 1.449–0.4* HbA1c (%) + 0.012 × Age (year). There were no changes in body mass in diabetic or nondiabetic patients. In diabetic patients taking medication, 63.4% of patients needed less medication.

Conclusions

Eradication of HCV improves glycemic control, indicated by a 0.4% decrease in HbA1c in diabetes.

The association between metabolic syndrome and Hepatitis C virus infection in the United States

PURPOSE

Hepatitis C virus (HCV) infection is the prevalent risk factor for chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC) worldwide. The association between metabolic syndrome (MetS) and HCV infection has not been studied effectively, particularly among different ethnic/racial groups in the US.

METHODS

A retrospective cross-sectional study was conducted using data from the National Health and Nutrition Examination Survey (1999-2014). Unadjusted and adjusted associations were summarized using the prevalence ratio (PR) and 95% confidence interval (CI) after exploring possible interactions.

RESULTS

In the overall population, MetS was significantly associated with HCV infection with an interaction of age. After adjusting for all potential confounders, MetS was found to be significantly associated with HCV among non-obese and younger adults of age less than 60 years (PR 1.67, 95% CI 1.21-2.30, p = 0.002). MetS was also associated with an increased prevalence of HCV in each racial/ethnic group, while the association was strongly modified by age and obesity status of the subjects in different ethnic/racial groups.

CONCLUSIONS

MetS or its components are associated with an increased prevalence of HCV in some sub-populations of all ethnic/racial groups in the US. A better understanding of the pathophysiology of MetS associated with HCV is important as MetS may have a role in HCV infection treatment outcomes.

Procoagulant imbalance influences cardiovascular and liver damage in chronic hepatitis C independently of steatosis

BACKGROUND & AIMS

Patients with chronic HCV infection besides hepatitis often present cardiovascular damage, the pathogenesis of which is not defined. In chronic liver diseases, including NAFLD and cirrhosis, a procoagulant imbalance, potentially responsible for atherosclerosis has been reported. We aimed at evaluating whether a procoagulant imbalance is present also in non-cirrhotic patients with HCV infection and whether the procoagulant imbalance correlates with cardiovascular damage. The correlation between the procoagulant imbalance, coexisting steatosis, and liver fibrosis was analysed.

METHODS

From 2014 to 2018, 393 subjects (205 patients with chronic HCV infection from two liver units and 188 controls) were enrolled. Metabolic, cardiovascular, liver assessment and coagulation parameters-procoagulants (FII and FVIII) and anticoagulants (antithrombin and protein C [PC]), endogenous thrombin potential (ETP), peak-thrombin and their ratios (with/without thrombomodulin)-were determined.

RESULTS

The procoagulant imbalance (defined as high FVIII, FVIII/PC ratio, ETP-ratio and peak-thrombin-ratio (with/without thrombomodulin)) was significantly higher in patients with chronic HCV than controls. Steatosis was detected in 87 patients (42%). No difference in coagulation imbalance, carotid and cardiac parameters and severity of liver fibrosis was observed in patients with or without steatosis, despite the latter had less severe metabolic alterations. The FVIII/PC ratio was independently associated with carotid intima-media thickness (coefficient 0.04, 95% CI 0.002-0.07, P = .04) and liver fibrosis (coefficient 0.64, 95% CI 0.37-0.92, P < .0001).

CONCLUSION

Patients with HCV infection, even in the absence of cirrhosis have a procoagulant-imbalance that possibly plays a role in increasing the risk of cardiovascular disease and progression of fibrosis.

Sustained virological response and metabolic risk factors are associated with mortality in patients with chronic hepatitis C

BACKGROUND AND AIM

Previous studies have reported that sustained virological response (SVR) to interferon-based treatment reduces the risk of mortality in chronic hepatitis C (CHC) patients, mainly in cirrhotic patients. A population-based study reported that metabolic risk factors increase the risk of mortality in CHC patients. We aim to investigate the association between SVR, metabolic risk factors and mortality in CHC patients with and without advanced fibrosis.

METHODS

We collected data from 1452 CHC patients who underwent interferon-based therapy. All patients underwent liver biopsy prior to therapy. Mild fibrosis was defined as a modified Knodell score of 0-2, while advanced fibrosis was defined as a score of 3-4.

RESULTS

1452 patients were followed up for a median (IQR) of 6.6 (4.2-9.4) years, 1124 patients (77.4%) achieved SVR, 619 patients (42.6%) were advanced fibrosis. 14 patients with mild fibrosis and 55 patients with advanced fibrosis died during follow-up period. According to multivariate Cox regression analyses, SVR reduced the risks of all-cause mortality (HR, 0.21; 95% CI, 0.12-0.37; P<0.001), liver-related mortality (HR, 0.19; 95% CI, 0.10-0.38; P < .001), and non-liver-related mortality (HR, 0.26; 95% CI, 0.10-0.71; P = 0.009) in the patients with advanced fibrosis. SVR also reduced the risk of liver-related mortality (HR, 0.09; 95% CI, 0.01-0.60; P = 0.013) in the patients with mild fibrosis. Anti-hypertensive treatment increased the risks of all-cause mortality (HR, 6.1; 95% CI: 1.66-22.54; P = 0.006) and liver-related mortality (HR, 12.3; 95% CI: 1.4-108.5; P = 0.02) in the patients with mild fibrosis.

CONCLUSION

SVR and metabolic risk factors are associated with mortality in CHC patients given interferon-based treatment.

Diabetes is associated with advanced fibrosis and fibrosis progression in non-genotype 3 chronic hepatitis C patients

BACKGROUND

Diabetes is a risk factor of fibrosis progression in chronic hepatitis C (CHC). However, only one longitudinal study exploring whether diabetes is associated with progression from non-cirrhotic liver to cirrhosis in CHC patients has been conducted.

AIMS

We investigated whether diabetes is associated with progression from non-cirrhotic liver to cirrhosis in non-genotype 3 CHC patients.

METHODS

A cohort consisting of 976 non-genotype 3 patients histologically proven to have CHC was studied. After excluding patients with biopsy-proven or ultrasound-identified cirrhosis, there were 684 patients without cirrhosis. All 684 patients underwent hepatocellular carcinoma surveillance using ultrasound every 6 months, with a median duration of follow-up evaluation of 102.4 months. During the follow-up period, 60 patients developed cirrhosis according to ultrasound findings.

RESULTS

For the subgroup of 684 patients without cirrhosis, Kaplan-Meier survival analyses showed no significantly different cumulative incidences of cirrhosis (log-rank test; P = 0.71) among the patients with diabetes as compared to those without. However, after making adjustments for age, gender, fibrosis, steatosis, sustained virological response status, and obesity using Cox's proportional hazard model, diabetes was found to be an independent predictor for cirrhosis (HR = 1.9; 95% CI = 1.05-3.43, P = 0.03).

CONCLUSIONS

Diabetes is associated with progression from non-cirrhotic liver to cirrhosis in non-genotype 3 CHC patients.

Effect of hepatitis B virus on steatosis in hepatitis C virus co-infected subjects: A multi-centre study and systematic review

It remains unclear whether hepatitis B virus (HBV) infection may modify the severity of viral steatosis in patients coinfected with chronic hepatitis C virus (HCV). We examined the influence of coinfection with HBV on prevalence of steatosis in chronic hepatitis C in a multi-centre cohort of HBV-HCV subjects, and by performing a systematic review and meta-analysis of the literature. We centrally and blindly assessed steatosis prevalence and severity in a cohort of HBV-HCV coinfected subjects compared to HCV and HBV monoinfected controls and we performed a systematic review of studies addressing the prevalence of steatosis in HBV-HCV subjects compared to HCV controls. In the clinical cohort, we included 85 HBV-HCV, 69 HBV and 112 HCV subjects from 16 international centres. There was no significant difference in steatosis prevalence between the HBV-HCV and the HCV groups (33% vs 45%, P = .11). In subgroup analysis, lean HBV-HCV subjects with detectable HBV DNA had less steatosis than lean HCV subjects matched for HCV viremia (15% vs 45%, P = .02). Our literature search identified 5 additional studies included in a systematic review. Overall, prevalence of steatosis > 5% was similar in HBV-HCV infection compared to HCV (pooled odds ratio [OR] 0.91, 95% CI 0.53-1.6) although there was significant heterogeneity (I² 69%, P = .007). In conclusion, although the prevalence of steatosis is similar in HBV-HCV compared to HCV subjects, our analysis suggests that there may be an inhibitory effect of HCV-induced steatogenesis by HBV in certain subgroups of patients.

Assessing risk of fibrosis progression and liver-related clinical outcomes among patients with both early stage and advanced chronic hepatitis C

OBJECTIVE

Assessing risk of adverse outcomes among patients with chronic liver disease has been challenging due to non-linear disease progression. We previously developed accurate prediction models for fibrosis progression and clinical outcomes among patients with advanced chronic hepatitis C (CHC). The primary aim of this study was to validate fibrosis progression and clinical outcomes models among a heterogeneous patient cohort.

DESIGN

Adults with CHC with ≥3 years follow-up and without hepatic decompensation, hepatocellular carcinoma (HCC), liver transplant (LT), HBV or HIV co-infection at presentation were analyzed (N = 1007). Outcomes included: 1) fibrosis progression 2) hepatic decompensation 3) HCC and 4) LT-free survival. Predictors included longitudinal clinical and laboratory data. Machine learning methods were used to predict outcomes in 1 and 3 years.

RESULTS

The external cohort had a median age of 49.4 years (IQR 44.3-54.3); 61% were male, 80% white, and 79% had genotype 1. At presentation, 73% were treatment naïve and 31% had cirrhosis. Fibrosis progression occurred in 34% over a median of 4.9 years (IQR 3.2-7.6). Clinical outcomes occurred in 22% over a median of 4.4 years (IQR 3.2-7.6). Model performance for fibrosis progression was limited due to small sample size. The area under the receiver operating characteristic curve (AUROC) for 1 and 3-year risk of clinical outcomes was 0.78 (95% CI 0.73-0.83) and 0.76 (95% CI 0.69-0.81).

CONCLUSION

Accurate assessments for risk of clinical outcomes can be obtained using routinely collected data across a heterogeneous cohort of patients with CHC. These methods can be applied to predict risk of progression in other chronic liver diseases.

The higher prevalence of truncal obesity and diabetes in American than Chinese patients with chronic hepatitis C might contribute to more rapid progression to advanced liver disease

BACKGROUND

Chronic hepatitis C virus (HCV) infection is the leading cause of cirrhosis and hepatocellular carcinoma (HCC) in the United States (US) and an emerging cause in China.

AIM

To compare the clinical characteristics of hepatitis C patients in the US and China, and factors influencing disease stage.

METHODS

Prospective study of 2 cohorts of HCV patients recruited at 1 site in the US and 3 sites in China. Standardised questionnaire on risk factors and medical history were used and diagnosis of cirrhosis and HCC was based on pre-defined criteria.

RESULTS

One thousand nine hundred and fifty seven patients (1000 US and 957 China) were enrolled. US patients were more likely to be men (61.4% vs 48.5%), older (median age 57 vs 53 years), obese (38.4% vs 16.8%) and diabetic (21.8% vs 10.8%). A significantly higher per cent of US patients had cirrhosis (38.2% vs 16.0%) and HCC (14.1% vs 2.7%). Investigator estimated time at infection in US was 10 years earlier than in Chinese patients but US patients were more likely to have advanced disease even after stratifying for duration of infection. Study site in the US, older age, truncal obesity, diabetes and prior HCV treatment were significant predictors of advanced disease on multivariate analysis.

CONCLUSIONS

HCV patients in the US had more advanced liver disease than those in China. We speculate that underlying fatty liver disease may be a major contributor to this difference, and management of glycometabolic abnormalities should occur in parallel with anti-viral therapy to achieve optimal outcomes.

The impact of nutrition on quality of life of patients with hepatitis C

PURPOSE OF REVIEW

The aim of this study was to review the most recent aspects of nutrition and its impact on health-related quality of life (HRQOL) in patients with chronic hepatitis C (CHC).

RECENT FINDINGS

Low HRQOL scores have been found in all stages of hepatitis C virus (HCV) infection. Of the factors linked to HRQOL, three aspects should be emphasized, nutritional status, physical activity and mental health status. Regarding the nutrition and metabolic conditions, a broad spectrum of nutritional disorders may impact on HRQOL of patients with CHC.

SUMMARY

Malnutrition, which is a significant comorbidity in end-stage of all chronic liver diseases, has been recognized as a significant factor related to poor HRQOL. Of note, in individuals chronically infected with HCV, low muscle skeletal mass, an early indicator of undernourishment, precedes the development of cirrhosis. Because of the strict linkage between HRQOL, nutrition and physical activity, the assessment of the musculoskeletal system abnormalities in every patient with CHC, independently of the stage of the liver disease, is of utmost relevance. Maintenance of healthy skeletal muscle is essential to reduce the negative effects of sarcopenia on HRQOL. Otherwise, overweight/obesity and chronic HCV infection can cause insulin resistance, which has been associated with HRQOL impairment.

International therapeutic guidelines for patients with HCV-related extrahepatic disorders. A multidisciplinary expert statement

Hepatitis C virus (HCV) is both hepatotrophic and lymphotropic virus that causes liver as well extrahepatic manifestations including cryoglobulinemic vasculitis, the most frequent and studied condition, lymphoma, and neurologic, cardiovascular, endocrine-metabolic or renal diseases. HCV-extrahepatic manifestations (HCV-EHMs) may severely affect the overall prognosis, while viral eradication significantly reduces non-liver related deaths. Different clinical manifestations may coexist in the same patient. Due to the variety of HCV clinical manifestations, a multidisciplinary approach along with appropriate therapeutic strategies are required. In the era of interferon-free anti-HCV treatments, international recommendations for the therapeutic management of HCV-EHMs are needed. This implies the need to define the best criteria to use antivirals and/or other therapeutic approaches. The present recommendations, based on qualified expert experience and specific literature, will focus on etiological (antiviral) therapies and/or traditional pathogenetic treatments that still maintain their therapeutic utility.

Hepatitis C-related cirrhosis. Current status

Chronic hepatitis C virus (HCV) infection affects around 150 million people. It is a leading cause of liver related morbidity and mortality through its predisposition to liver fibrosis, cirrhosis and end-stage liver complications. New treatments based on direct-acting antivirals have opened a new era in the management of HCV cirrhosis. They allow for HCV eradication without substantial side effects in almost all cirrhotic patients, reducing the risk of hepatocellular carcinoma, liver decompensation and mortality. This review provides an update on HCV cirrhosis. The paper focuses on the disease burden and major progresses in the diagnosis, follow-up and treatment of this patient subgroup.

Hepatitis C virus and cardiovascular: A review

Chronic hepatitis C virus (HCV) infection is a systemic disease that leads to increased risks of cirrhosis and its complications, as well as extrahepatic disturbances, including immune-related disorders and metabolic alterations such as insulin resistance and steatosis. Recent accumulating evidence suggests that HCV infection can increase cardiovascular risk, and that viral eradication can improve cardiovascular outcomes in the clinical setting. These data are strengthened by evidence identifying potential mechanisms (in)directly linking HCV infection to vascular damage. However, the high prevalence of both HCV infection and cardiovascular alterations, as well as the presence of contrasting results not identifying any association between HCV infection and cardiovascular dysfunction, provides uncertainty about a direct association of HCV infection with cardiovascular risk. Further studies are needed to clarify definitively the role of HCV infection in cardiovascular alterations, as well as the impact of viral eradication on cardiovascular outcomes. These features are now more attractive, considering the availability of new, safe, and very effective interferon-free antiviral agents for the treatment of HCV infection. This review aims to discuss carefully available data on the relationship between HCV infection and cardiovascular risk.

Liver steatosis in hepatitis C patients

There is controversy regarding some aspects of hepatitis C virus (HCV) infection-associated liver steatosis, and their relationship with body fat stores. It has classically been found that HCV, especially genotype 3, exerts direct metabolic effects which lead to liver steatosis. This supports the existence of a so called viral steatosis and a metabolic steatosis, which would affect HCV patients who are also obese or diabetics. In fact, several genotypes exert metabolic effects which overlap with some of those observed in the metabolic syndrome. In this review we will analyse the pathogenic pathways involved in the development of steatosis in HCV patients. Several cytokines and adipokines also become activated and are involved in “pure” steatosic effects, in addition to inflammation. They are probably responsible for the evolution of simple steatosis to steatohepatitis, making it difficult to explain why such alterations only affect a proportion of steatosic patients.

Hepatitis C virus-induced hepatocellular carcinoma

Hepatitis C virus (HCV) is a leading etiology of hepatocellular carcinoma (HCC). The interaction of HCV with its human host is complex and multilayered; stemming in part from the fact that HCV is a RNA virus with no ability to integrate in the host's genome. Direct and indirect mechanisms of HCV-induced HCC include activation of multiple host pathways such as liver fibrogenic pathways, cellular and survival pathways, interaction with the immune and metabolic systems. Host factors also play a major role in HCV-induced HCC as evidenced by genomic studies identifying polymorphisms in immune, metabolic, and growth signaling systems associated with increased risk of HCC. Despite highly effective direct-acting antiviral agents, the morbidity and incidence of liver-related complications of HCV, including HCC, is likely to persist in the near future. Clinical markers to selectively identify HCV subjects at higher risk of developing HCC have been reported however they require further validation, especially in subjects who have experienced sustained virological response. Molecular biomarkers allowing further refinement of HCC risk are starting to be implemented in clinical platforms, allowing objective stratification of risk and leading to individualized therapy and surveillance for HCV individuals. Another role for molecular biomarker-based stratification could be enrichment of HCC chemoprevention clinical trials leading to smaller sample size, shorter trial duration, and reduced costs.

Fatty Acids Induce a Pro-Inflammatory Gene Expression Profile in Huh-7 Cells That Attenuates the Anti-HCV Action of Interferon

The pathogenesis of nonalcoholic steatohepatitis is primarily an immune-driven disease and a known factor associated with treatment failure of chronic hepatitis C with interferon (IFN) and ribavirin. We studied the hepatocyte response in a model of steatosis at the transcriptome level and the antiviral action of IFN against hepatitis C virus (HCV) in this setting. In this study, we have shown that lipid loading (oleic acid and palmitic acid, OA:PA) of Huh-7 cells leads to increased expression of classical interferon-stimulated genes (ISGs) and NF-κβ-dependent pro-inflammatory genes. A selective blocker of Toll-like receptor (TLR)2 signaling suppressed NF-κβ promoter activity by OA:PA, suggesting that free fatty acids (FFAs) act as a TLR2 pathogen-associated molecular pattern. Furthermore, in the presence of OA:PA, IFN stimulation and HCV infection (Jc1) increased ISG expression. Somewhat counterintuitive to the increase in ISGs, the anti-HCV activity of IFN was attenuated in the presence of OA:PA. Interestingly, the combination of OA:PA, HCV, and IFN-α stimulation resulted in a significant increase in CXCL8 protein production, a cytokine known to have anti-IFN modulating activity. Thus, in an in vitro model of steatosis, the FFAs OA and PA drive an NF-κβ-dependent inflammatory and ISG gene expression profile via TLR2 activation. Furthermore, FFA synergistically increases IFN-driven gene expression that may account for HCV treatment failure in vivo.

Cure of HCV related liver disease

Chronic hepatitis C virus (HCV) causes chronic liver injury and can lead to cirrhosis and hepatocellular carcinoma (HCC). HCV can also interact with the immune system to cause several HCV related disorders including essential mixed cryoglobulinemia, vasculitis, dermatitis, glomerulonephritis and lymphoma. A strong association between HCV and diabetes mellitus also exists. These extrahepatic features may lead to increased fatigue and a reduced quality of life. It is now possible to cure most patients with chronic HCV using oral antiviral therapy. Many of these HCV-related disorders and symptoms can be cured when HCV is eradicated. However, some patients may have irreversible injury to extrahepatic sites, cirrhosis that cannot resolve, an increased risk for HCC, persistent fatigue and a reduced quality of life, despite achieving sustained virological response.