Serum lipid pattern in chronic hepatitis C: histological and virological correlations

Biomarkers of Hepatic Toxicity: An Overview

Background

Hepatotoxicity is the foremost issue for clinicians and the primary reason for pharmaceutical product recalls. A biomarker is a measurable and quantifiable attribute used to evaluate the efficacy of a treatment or to diagnose a disease. There are various biomarkers which are used for the detection of liver disease and the intent of liver damage.

Objective

This review aims to investigate the current state of hepatotoxicity biomarkers and their utility in clinical settings. Using hepatic biomarkers, the presence of liver injury, its severity, prognosis, causative agent, and type of hepatotoxicity can all be determined.

Methods

Relevant published articles up to 2022 were systematically retrieved from MEDLINE/PubMed, SCOPUS, EMBASE, and WOS databases using keywords such as drug toxicity, hepatotoxicity biomarkers, biochemical parameters, and nonalcoholic fatty liver disease.

Results

In clinical trials and everyday practice, biomarkers of drug-induced liver injury are essential for spotting the most severe cases of hepatotoxicity. Hence, developing novel biomarker approaches to enhance hepatotoxicity diagnosis will increase specificity and/or identify the person at risk. Importantly, early clinical studies on patients with liver illness have proved that some biomarkers such as aminotransferase, bilirubin, albumin, and bile acids are even therapeutically beneficial.

Conclusions

By assessing the unique signs of liver injury, health care professionals can rapidly and accurately detect liver damage and evaluate its severity. These measures contribute to ensuring prompt and effective medical intervention, hence reducing the risk of long-term liver damage and other major health concerns.

Serum infrared spectral profile is predictive of the degree of hepatic fibrosis in chronic hepatitis C patients

Assessment of liver fibrosis is crucial to guide the therapeutic strategy in patients with chronic liver disease. We investigated the potential of serum Fourier transform infrared (FTIR) spectroscopy for assessing the degree of hepatic fibrosis in patients with chronic hepatitis C (CHC). The study was conducted on dried serum samples from 94 CHC patients at different histological stages of hepatic fibrosis: METAVIR F0 (n = 20), F1 (n = 17), F2 (n = 20), F3 (n = 20) and F4 (n = 17). Transmission FTIR spectra were acquired in the 4000-400 cm-1 range. Wavenumbers were selected by genetic algorithm (GA) according to their diagnostic performance as assessed by a partial least squares discriminant analysis (PLS-DA) model using a training and a validation set to differentiate severe stages of fibrosis from mild or moderate ones. The GA procedure was applied 50 times on randomly selected sets. Furthermore, the best set of wavenumbers was re-tested in 1000 randomly selected validation sets. Wavenumbers selected by GA corresponded to functional groups present in lipids, proteins, and carbohydrates. This model allowed to identify patients with cirrhosis (METAVIR F4), patients with advanced fibrosis (METAVIR F3 and F4), and patients with significant fibrosis (METAVIR F2, F3 and F4), with AUROC (Area Under the Receiver Operating Characteristic) of 0.88, 0.85 and 0.85, respectively. Thus, serum FTIR spectroscopy appears to have a strong potential as a new diagnostic tool for assessing the degree of fibrosis in patients with chronic liver disease.

Dyslipidemia and impaired liver function biomarkers in patients with hepatitis B liver cirrhosis

Objective

This study was conducted to determine changes in lipid metabolism and liver enzyme status among HBV-positive patients with liver cirrhosis.

Methods

A total of 300 HBV-positive patients with liver cirrhosis and 200 healthy controls were included in this case-control study. The patients were recruited from several tertiary care hospitals in Lahore from March to October 2021. Their blood samples were collected and analyzed for HBsAg, HBeAg, liver function biomarkers, and serum lipids. Liver cirrhosis was confirmed by ultrasonography and liver biopsy. The data were analyzed with chi-square test, Student's t-test, logistic regression, and ROC curve analysis.

Results

Serum liver function biomarkers were significantly higher, and serum lipid levels were substantially lower, in HBV-infected patients with liver cirrhosis than in controls. No significant associations of sex and age with dyslipidemia were observed in patients with cirrhosis. Grading and staging scores for liver cirrhosis were negatively associated with total cholesterol levels. Moreover, sex and high levels of liver enzymes were significant risk factors associated with dyslipidemia in HBV-positive patients with liver cirrhosis. The optimum cut-off values of liver enzymes and serum lipids for the prognosis of liver cirrhosis exceeded normal ranges.

Conclusion

Serum lipid concentrations may serve as a clinical index to assess liver damage in HBV-positive patients.

Burden, Outcome, and Comorbidities of Extrahepatic Manifestations in Hepatitis C Virus Infection

Hepatitis C virus (HCV) is a significant cause of chronic liver diseases worldwide and is associated with negative consequences, including cirrhosis, hepatic decompensation, hepatocellular carcinoma, and increased risk of mortality. In addition to liver-related morbidities, HCV is also associated with several extrahepatic manifestations, including mixed cryoglobulinemia, diabetes mellitus, cardiocerebrovascular disease, lymphoma, and autoimmune diseases. These non-liver-related complications of HCV increase the complexity of this disease and can contribute to the economic burden, morbidity, quality of life, and mortality throughout the world. Therefore, understanding how this virus can contribute to each extrahepatic manifestation is worth investigating. Currently, the advancement of HCV treatment with the advent of direct-acting anti-viral agents (DAAs) has led to a high cure rate as a result of sustained virologic response and tremendously reduced the burden of extrahepatic complications. However, HCV-associated extrahepatic manifestations remain a relevant concern, and this review aims to give an updated highlight of the prevalence, risk factors, associated burdens, and treatment options for these conditions.

ABCA1 Polymorphism R1587K in Chronic Hepatitis C Is Gender-Specific and Modulates Liver Disease Severity through Its Influence on Cholesterol Metabolism and Liver Function: A Preliminary Study

Chronic hepatitis C (CHC) progression is highly variable and can be influenced by lipid metabolism. The ATP-binding cassette transporter A1 (ABCA1) is involved in lipid metabolism and mediates cholesterol efflux from liver cells. ABCA1 gene polymorphism rs2230808 (R1587K) modulates lipid levels as it is located in an ABCA1 protein domain, which is essential for cholesterol efflux. We aimed to analyze the role of ABCA1 polymorphism R1587K (rs2230808) in modulating the biochemical parameters of lipid metabolism and liver function and its association with liver disease severity, according to gender. A total of 161 CHC patients were clinically, histologically, and biochemically evaluated. Genotyping was performed by melting-curve analysis and statistical analysis by SPSS 24.0. There were significant differences between ABCA1_rs2230808 genotypes and total cholesterol, γGT (γ-glutamyl-transpeptidase), and HCV-RNA. Gender differences: in females, ABCA1_rs2230808 (GG or GA) was associated with higher HCV-RNA serum levels; in males, ABCA1_rs2230808 (GG or GA) was associated with higher γGT, lower total cholesterol, increased risk for γGT ≥ 38 UI/L, and total cholesterol < 4.92 mmol/L. Only in the case of males were higher γGT and lower total cholesterol associated with severe fibrosis and steatosis. Total cholesterol < 4.92 mmol/L also associates with severe necroinflammation. We conclude that ABCA1_rs2230808 is gender-specific. ABCA1_rs2230808 Allele G was associated with different clinical and biochemical parameters, which are related to more severe liver disease.

A Peptide HEPFYGNEGALR from Apostichopus japonicus Alleviates Acute Alcoholic Liver Injury by Enhancing Antioxidant Response in Male C57BL/6J Mice

Liver-related disease caused by alcohol is a frequent disorder of the hepatic tract. Heavy consumption of alcohol in a short period causes oxidative damage to the liver. Sea cucumber is abundant in nutrients and its various extracts have been studied for antioxidant properties. One peptide was isolated and identified from Apostichopus japonicus in our recent study. We investigated the benefits of the peptide in a model of acute ethanol-induced male C57BL/6J mice. Dietary intake of the peptide could attenuate hepatomegaly, hepatitis and the accumulation of lipid droplets, and increase antioxidant enzyme activities in mice with acute alcoholic liver injury. The results indicated that a 20 mg/kg peptide supplement could activate the Nrf2/HO-1 pathway and block the nuclear translocation of NF-κB to alleviate oxidative stress and inflammation. In addition, the preventive effects of peptide supplementation may be related to autophagy. This study suggests that dietary supplementation with a sea cucumber-derived peptide is one of the potential candidates to alleviate acute alcoholic liver injury.

Infection with the hepatitis C virus causes viral genotype-specific differences in cholesterol metabolism and hepatic steatosis

Lipids play essential roles in the hepatitis C virus (HCV) life cycle and patients with chronic HCV infection display disordered lipid metabolism which resolves following successful anti-viral therapy. It has been proposed that HCV genotype 3 (HCV-G3) infection is an independent risk factor for hepatocellular carcinoma and evidence suggests lipogenic proteins are involved in hepatocarcinogenesis. We aimed to characterise variation in host lipid metabolism between participants chronically infected with HCV genotype 1 (HCV-G1) and HCV-G3 to identify likely genotype-specific differences in lipid metabolism. We combined several lipidomic approaches: analysis was performed between participants infected with HCV-G1 and HCV-G3, both in the fasting and non-fasting states, and after sustained virological response (SVR) to treatment. Sera were obtained from 112 fasting patients (25% with cirrhosis). Serum lipids were measured using standard enzymatic methods. Lathosterol and desmosterol were measured by gas-chromatography mass spectrometry (MS). For further metabolic insight on lipid metabolism, ultra-performance liquid chromatography MS was performed on all samples. A subgroup of 13 participants had whole body fat distribution determined using in vivo magnetic resonance imaging and spectroscopy. A second cohort of (non-fasting) sera were obtained from HCV Research UK for comparative analyses: 150 treatment naïve patients and 100 non-viraemic patients post-SVR. HCV-G3 patients had significantly decreased serum apoB, non-HDL cholesterol concentrations, and more hepatic steatosis than those with HCV-G1. HCV-G3 patients also had significantly decreased serum levels of lathosterol, without significant reductions in desmosterol. Lipidomic analysis showed lipid species associated with reverse cholesterol transport pathway in HCV-G3. We demonstrated that compared to HCV-G1, HCV-G3 infection is characterised by low LDL cholesterol levels, with preferential suppression of cholesterol synthesis via lathosterol, associated with increasing hepatic steatosis. The genotype-specific lipid disturbances may shed light on genotypic variations in liver disease progression and promotion of hepatocellular cancer in HCV-G3.

Development and Validation of a Model for Prediction of End-Stage Liver Disease in People With HIV

BACKGROUND

End-stage liver disease (ESLD) is a leading cause of non-AIDS-related death among people with HIV (PWH). Factors that increase the progression of liver disease include comorbidities and HIV-specific factors, but we currently lack a tool to apply this evidence into clinical practice.

METHODS

We developed and validated a risk prediction model for ESLD among PWH who received care in 12 cohorts of the North American AIDS Cohort Collaboration on Research and Design between 2000 and 2016 and had fibrosis-4 index > 1.45. The first occurrence of ascites, variceal bleed, spontaneous bacterial peritonitis, or hepatic encephalopathy was verified by standardized medical record review. The Bayesian model averaging was used to select predictors among biomarkers and diagnoses and the Harrell C statistic to assess model discrimination.

RESULTS

Among 13,787 PWH in the training set, 82% were men and 54% were Black with a mean age of 48 years. Three hundred ninety ESLD events occurred over a mean 5.4 years. Among the ESLD cases, 52% had hepatitis C virus, 15% hepatitis B virus, and 31% alcohol use disorder. Twelve factors together predicted ESLD risk moderately well (C statistic 0.79, 95% confidence interval: 0.76 to 0.81): age, sex, race/ethnicity, chronic hepatitis B or C, and routinely collected laboratory values reflecting hepatic impairment (serum albumin, aspartate aminotransferase, total bilirubin, and platelets) and lipid metabolism (triglycerides, high-density lipoprotein, and total cholesterol). Our model performed well in the test set (C statistic 0.81, 95% confidence interval: 0.76 to 0.86).

CONCLUSION

This model of readily accessible clinical parameters predicted ESLD in a large diverse population of PWH.

Long-term surveillance of liver histological changes in chronic hepatitis C patients completing pegylated interferon-α plus ribavirin therapy: an observational cohort study

BACKGROUND

For chronic hepatitis C (CHC) patients completing pegylated interferon (PegIFN)-α/ribavirin therapy, long-term liver histological changes remain largely unexplored.

METHODS

This observational cohort study included 85 CHC patients completing PegIFN-α/ribavirin therapy with liver biopsies performed at baseline and the end of surveillance (EOS). Median years between paired biopsies were 6.75 (interquartile range: 5.63-7.54).

RESULTS

In patients with baseline METAVIR fibrosis stages (F) <4 (able to undergo fibrosis progression; n = 77), cases achieving sustained virological response (SVR) (n = 52) had a significantly lower rate of fibrosis progression than non-SVR cases (n = 25) (3.8% versus 24.0%, p = 0.012). Among the entire cohort (n = 85), the rate of activity response [METAVIR activity grades (A) decreasing or maintaining at A0] in SVR cases (n = 59) was significantly higher than that in non-SVR cases (n = 26) (94.9% versus 65.4%, p = 0.001). For SVR cases among the entire cohort, independent predictors of fibrosis clearance included baseline F <2 [odds ratio (OR) = 7.877, p = 0.042] and aspartate transaminase (AST) levels declining by >70% at EOS compared with baseline (OR = 9.013, p = 0.038). For non-SVR cases among the entire cohort, baseline AST levels >80 U/l and glucose levels ⩽ 105 mg/dl independently predicted significant fibrosis (F2/F3/F4) at EOS (OR = 12.558, p = 0.049) and activity response (OR = 17.741, p = 0.047), respectively.

CONCLUSIONS

Among CHC patients completing PegIFN-α/ribavirin therapy, SVR lowers the risk of liver histological progression but does not guarantee fibrosis clearance. For SVR cases, those with baseline F ⩾ 2 or without significantly declined follow-up AST levels should be specifically monitored. As for non-SVR cases, those with a higher baseline AST or glucose level should preferentially receive retreatment.

The liver steatosis severity and lipid characteristics in primary biliary cholangitis

Background

Patients with primary biliary cholangitis (PBC) often have comorbid dyslipidemia, and determining the degree of hepatic steatosis can help predict the risk of cardiovascular events in PBC patients. The aim of our study was to analyze the characteristics of lipid distribution and the degree of hepatic steatosis in PBC.

Methods

We retrospectively analyzed 479 cases of PBC, chronic hepatitis B (CHB), chronic hepatitis C (CHC), non-alcoholic fatty liver disease (NAFLD), and healthy subjects (Normal) diagnosed by liver biopsy or definitive clinical diagnosis. Controlled attenuation parameter (CAP) values were applied to assess the degree of steatosis of the liver, and lipid levels were also compared in the five cohorts.

Results

We found that among the five groups of subjects, the PBC group had the lowest CAP values (P < 0.001), and the high-density lipoprotein cholesterol (HDL-C) level in the PBC group was higher than normal, CHC and CHB group (P = 0.004, P = 0.033, P < 0.001, respectively).In the multivariate linear analysis, only BMI (β = 1.280, P = 0.028), ALP (β = − 0.064, P = 0.012), TBA (β = − 0.126, P = 0.020), TG (β = 12.520, P = 0.000), HDL-C (β = − 11.338, P = 0.001) and LDL-C (β = 7.012, P = 0.002) were independent predictors of CAP.

Conclusions

Among PBC, CHB, CHC, NAFLD and healthy subjects, PBC had the lowest degree of hepatic steatosis and higher HDL-C levels, all of which were found to be protective factors against atherosclerosis and cardiovascular risk and would provide a valuable reference for the risk of developing cardiovascular events in PBC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-01974-4.

LDL receptor and pathogen processes: Functions beyond normal lipids

Although the role of the LDL receptor concerning lipids is well known, its role in various viral and parasitic infections, and in regulating the inflammatory response is poorly understood. Several infectious agents use the LDL receptor as a port of entry, and others depend on it for their cycle of infection. In this review, we focus on the discovery, structure, and normal function of the LDL receptor, as well as its role in a selection of infections. The LDL receptor plays an important role in certain infections and is a potential target for treatment deserving further research.

Evaluation of Safety and Effectiveness of Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Alafenamide Switch Followed by Ledipasvir/Sofosbuvir HCV Therapy in HIV-HCV Coinfection

Background

We conducted a pilot study assessing the feasibility, efficacy, and safety of a simplified combination HIV antiretroviral and hepatitis C virus (HCV) antiviral regimen in HIV–HCV coinfection.

Methods

Participants on suppressive antiretrovirals and HCV genotype 1 infection were switched to single-tablet daily-dosed elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) and 1 month later initiated single-tablet-regimen daily-dosed ledipasvir-sofosbuvir for 12 weeks. E/C/F/TAF was continued during HCV treatment and for 12 weeks after.

Results

Twenty-six individuals were screened, 25 enrolled, and 23 completed all HIV and HCV treatment. Participants were predominantly male, with a mean age (SD) of 55 (7.5) years. The median transient elastography score (interquartile range [IQR]) was 5.9 (5.3 to 7.6) kPa, and the mean CD4 count (SD) was 579 (223) cells/µL. The median adherence to HCV medications, assessed by pill count, was 100% (95% confidence interval [CI], 100%–100%), and HIV ranged from 99% to 100% (100%; 95% CI, 90%–100%) over the 7-month study duration. HIV undetectability was maintained in all but 1 participant enrolled with unsuspected multiclass resistance. Treatment was well tolerated, with no study medication modification due to adverse events and no serious adverse event related to the study drug. All participants achieved sustained virological response. The mean CD4 count (SD) increased to 673 (361) cells/µL, and the fibrosis score (IQR) declined to 5.2 (4.4 to 7.4) kPa by week 12 after HCV treatment. There was no treatment effect on glucose metabolism. Cholesterol increased during and after treatment.

Conclusions

Provision of this 2-tablet daily HIV–HCV regimen is feasible, well tolerated, and safe, avoids drug–drug interactions between HIV and HCV medications, maintains HIV suppression in the absence of drug resistance, and is highly curative of HCV.

Long-term outcomes and risk factors of thyroid dysfunction during pegylated interferon and ribavirin treatment in patients with chronic hepatitis C infection in Taiwan

BACKGROUND

This study aimed to investigate the occurrence and risk factors of thyroid dysfunction (TD) in patients with chronic hepatitis C (CHC) infection in Taiwan.

METHODS

The data in this study were obtained from the Taiwan National Health Insurance Research (Taiwan NHIR) database between 2001 and 2013. CHC patients treated with pegylated interferon/ribavirin (PEG-IFN/RBV) were enrolled as case patients, and nontreated CHC patients were enrolled as controls and were matched at a control:case ratio of 3:1 by index date, age (± 3 years), and sex. We compared the cumulative incidence of TD between the cohorts at follow-up until 2013.

RESULTS

During the study period, 3810 cases and 9393 controls were included in the study. Among the study subjects, 173 (4.5%) case patients and 244 (2.6%) controls were diagnosed with TD during the follow-up period. The types of TD were hypothyroidism (42.9%), hyperthyroidism (31.2%), and thyroiditis (25.9%). Compared to controls during the 13-year follow-up, patients treated with PEG-IFN/RBV had a higher incidence rate of TD (P < 0.0001), as determined using the Kaplan-Meier method. Cox proportional hazards regression analysis showed that female sex (adjusted hazard ratio (HR): 1.49; 95% confidence interval (CI): 1.23-1.75; P < 0.001), treatment with PEG-IFN/RBV (HR: 1.68; 95% CI: 1.38-2.06; P < 0.001), hyperlipidemia (HR: 1.38; 95% CI: 1.12-1.71; P < 0.001), and past history of goiter (HR: 6.40; 95% CI: 5.00-8.18; P < 0.001) were independent predictors for the development of TD.

CONCLUSIONS

PEG-IFN/RBV treatment may be an independent risk factor for thyroid dysfunction among patients with hepatitis C virus (HCV) infection. Monitoring thyroid function keenly during PEG-IFN/RBV therapy in patients with chronic HCV infection is recommended for clinicians, especially for female patients and for patients with a history of hyperlipidemia and goiter.

Hepatitis C Direct Acting Antivirals and Ribavirin Modify Lipid but not Glucose Parameters

Chronic hepatitis C (HCV) infection perturbs lipid and glucose metabolism. The influence of direct acting antiviral (DAA) treatment and ribavirin on these measures was evaluated. Furthermore, the effect of HCV cure on these parameters was assessed. Participants were allocated to one of three 12-week treatment groups: non-cirrhotic genotype 1a-paritaprevir/ritonavir/ombitasvir/dasabuvir (PrOD) plus ribavirin; non-cirrhotic 1b-PrOD; compensated cirrhotic 1a or 1b-PrOD plus ribavirin. Fasting insulin, glucose, lipid and apolipoprotein measures were assessed at baseline, Treatment Weeks 4 and 12, and 12 and 24 weeks post-dosing. Twenty-three of 24 participants achieved SVR (PP= 23/24, 96% SVR). Overall, total cholesterol, low-density lipoprotein cholesterol (LDL-C), and triglyceride levels all increased in treatment and post-dosing. However, LDL-C levels decreased during treatment in ribavirin recipients. Fasting glucose, insulin, and HOMA-IR were unchanged during treatment and 12 weeks post-treatment. By 12 weeks post-treatment, controlled attenuation parameter (CAP) scores, a measure of steatosis, increased from baseline (mean 30.3 ± 63.5, p = 0.05). This regimen was safe and highly effective and did not influence glucose metabolism. Ribavirin exposure may mitigate some on-treatment lipid changes. Further mechanistic studies are needed to understand how ribavirin impacts lipid pathways, as there could be therapeutic implications. The metabolic pathophysiology of increased CAP score with HCV treatment requires explanation.

Control of progression towards liver fibrosis and hepatocellular carcinoma by SOCS3 polymorphisms in chronic HCV-infected patients

BACKGROUND & AIMS

Chronic Hepatitis C is one of the most important risk factors of liver cirrhosis and hepatocellular carcinoma. Before reaching these ultimate steps, insulin resistance triggered by hepatitis C virus infection is known to participate in the progression of liver disease. The present study aims to investigate the influence of two functional polymorphisms on SOCS3 mRNA expression and on the outcomes of CHC progression in a North African context.

PATIENTS & METHODS

In this case-control study, 601 Moroccan subjects composed of 200 healthy controls, 101 resolvers and 300 patients with persistent HCV infection including 95 mild chronic hepatitis, 131 Advanced Liver Diseases and 74 HCC were enrolled. They were genotyped for the 4874 A/G (rs4969170) and A + 930- > G (rs4969168) SOCS3 variants using TaqMan SNPs assays. SOCS3 mRNA expression was assessed using Real Time PCR technique.

RESULTS

Logistic regression analysis showed that variation at rs4969168 was associated with spontaneous clearance of HCV (P < 0.05). In addition, minor allele frequencies were significantly higher in AdLD patients when compared to the mCHC group both for rs4969168 (P = 7.0 E-04) and rs4969170 (P = 4.0 E-05). A significant association between haplotype and liver disease progression was also found. Moreover, SOCS3 mRNA was significantly more expressed in peripheral leukocytes from patients with HCC than in those from mCHC. Finally, rs4969170 was significantly associated with LDL-lipoprotein (P = 0.04), total cholesterol (P = 5.0 E-04), and higher fasting glucose levels (P = 0.005) in patients with persistent HCV infection.

CONCLUSIONS

Our results underline the importance of the functional SOCS3 polymorphisms in the modulation of CHC progression and suggest their contribution to HCC development by affecting its mRNA expression and perturbing key metabolic parameters.

The Correlation between miR-122 and Lipoprotein Lipase Expression in Chronic Hepatitis C Patients

Chronic HCV infection is strictly associated with host lipid/lipoprotein metabolism disorders. The study aimed to analyze the relationship between viral load, lipid profile, IFNγ, and the expression of miR-122 and LPL in the liver and PBMCs. Sera, PBMCs, and matching liver biopsies from 17 chronic hepatitis C patients were enrolled in this study. Collected data shows that liver (not PBMCs) miR-122 expression is positively correlated with HCV RNA load and IFNγ and reversely with LPL expression in CHC patients. Presented, for the first time, in this study, the reverse correlation of miR-122 and LPL expression in liver; miR-122 and LPL seem to be important factors of CHC infection.

Hepatitis C Virus Infection in the Older Patient

Hepatitis C virus (HCV) is the most common blood-borne infection in the United States and is of concern in older adults. HCV infection is associated with not only hepatic but also extrahepatic comorbidities common to the aging patient including diabetes, kidney and cardiovascular diseases, and neurocognitive impairment. The effect of direct-acting antiviral agents to treat HCV on these outcomes is limited. This article summarizes the literature regarding the epidemiology and natural history of HCV infection; the impact of age on clinical outcomes in HCV-infected persons; and current knowledge regarding safety and efficacy of HCV treatment regimens in the older patient.

The effect of antiviral therapy on serum lipid profiles in chronic hepatitis C

BACKGROUND

Low lipid profile is associated with hepatitis C virus (HCV) infection. Chronic HCV infection is the main cause of liver injury and serum lipid levels during antiviral treatment. We aimed to evaluate the effect of antiviral treatment on the change of lipid profiles during HCV treatment.

METHODS

Total 863 patients who complete the interferon-based therapy in Kaohsiung Medical University Hospital were included in this study. The lipid profile measured and evaluated in baseline and after 6 months of the treatment.

RESULTS

Sustained virological response (SVR) was achieved in 81.2% of all patients. The baseline triglycerides (TG) levels in the SVR group and non SVR groups were similar. The TG levels at 6 months after cessation of the treatment was significantly elevated in SVR group (102.9±57.0 mg/dL, p=0.0001) but did not elevated in non SVR group (94.5±45.6 mg/dL, p=0.690) compared with baseline TG levels. After adjusting patients by four indexes for fibrosis (FIB4) in cut-off point 3.25, serum TG levels significantly increased in low FIB4 group (103.2±57.9 mg/dL, p=0.0001) but not in high FIB4 group (98.1±49.6 mg/dL, p=0.095) after 6 months end of the treatment. Serum TG level was increased greater in patients who had low FIB4 score and patients who achieved SVR (baseline 89.1±34.8 mg/dL; 6 months after treatment 104.3±59.3 mg/dL, paired T test p=0.0001).

CONCLUSION

The clearance of the HCV RNA is the main determinant of the increase of lipids after PegIFN/RBV treatment. However advanced fibrosis also has an effect in increase of lipids after the treatment.

Autoantibody to apolipoprotein A-1 in hepatitis C virus infection: a role in atherosclerosis?

Background/purpose

One to three per cent of the world’s population has hepatitis C virus (HCV) infection, which is not only a major cause of liver disease and cancer but also associated with an increased risk of atherosclerosis, despite an ostensibly favourable lipid profile. Autoantibodies are frequent in HCV infection and emerging evidence shows that autoantibodies could be valuable for cardiovascular disease (CVD) risk stratification. This study investigated a novel independent biomarker of CVD, autoantibodies to apolipoprotein A-1 (anti-apoA-1 IgG) and lipids in patients with chronic HCV before, during and after direct-acting anti-viral (DAA) therapy.

Methods

Eighty-nine blinded serum samples from 27 patients with advanced chronic HCV were assayed for lipids and anti-apoA-1 IgG by ELISA.

Results

Pre-treatment HCV viral load correlated with high-density lipoprotein cholesterol (HDL-C, r = 0.417; p = 0.042) and negatively with apolipoprotein (apo)B (r = − 0.497; p = 0.013) and markers of CVD risk, the apoB/apoA-1 ratio (r = − 0.490; p = 0.015) and triglyceride level (TG)/HDL-C ratio (r = − 0.450; p = 0.031). Fourteen (52%) of 27 patients had detectable anti-apoA-1 IgG autoantibodies pre-treatment; only two became undetectable with virological cure. Autoantibody-positive sera had lower apoA-1 (p = 0.012), HDL-C (p = 0.009) and total cholesterol (p = 0.006) levels.

Conclusions

This is the first report of the presence of an emerging biomarker for atherosclerosis, anti-apoA-1 IgG, in some patients with HCV infection. It may be induced by apoA-1 on the surface of HCV lipoviral particles. The autoantibodies inversely correlate with apoA-1 and HDL levels and may render HDL dysfunctional. Whether these hypothesis-generating findings have clinical implications in HCV patients requires further study.

Impact of hepatitis C virus infection on long-term mortality after acute myocardial infarction: a nationwide population-based, propensity-matched cohort study in Taiwan

INTRODUCTION

The influence of hepatitis C virus (HCV) infection on long-term outcomes of patients with acute myocardial infarction (AMI) is unclear. Therefore, this study aimed to analyse the impact of HCV infection on 12-year mortality rates after AMI using data from the Taiwan National Health Insurance Research Database (NHIRD).

METHODS

NHIRD data for approximately 23 000 000 patients between January 2000 and December 2012 were analysed. A total of 186 112 cases of first AMI admission were identified. A total of 4659 patients with HCV infection not receiving interferon therapy were enrolled and divided into those with (n=107) or without (n=4552) cirrhosis. Using one-to-one matching, 4552 matched controls were included in the final analysis.

RESULTS

The 12-year mortality rate was significantly higher in patients with AMI with HCV infection and cirrhosis than in those with HCV infection but without cirrhosis (P<0.0001) or controls (P<0.0001). Patients with HCV infection but without cirrhosis had significantly higher long-term mortality rates than the matched controls (P<0.0001). The HR for mortality was higher in patients with HCV infection (HR 1.12; 95% CI 1.06 to 1.18). HCV influenced outcomes among the subgroups of patients who were male (HR 1.15) and those who had hypertension (HR 1.14).

CONCLUSIONS

HCV infection influenced the 12-year mortality rates of patients with AMI, especially those who were male and those who had hypertension. Cirrhosis further increased the long-term mortality rates of patients with AMI with HCV infection.

Abnormalities of Lipoprotein Levels in Liver Cirrhosis: Clinical Relevance

Progressive lipoprotein impairment occurs in liver cirrhosis and is associated with increased morbidity and mortality. The present review aims to summarize the current evidence regarding the prognostic value of lipoprotein abnormalities in liver cirrhosis and to address the need of a better prognostic stratification of patients, including lipoprotein profile assessment. Low levels of lipoproteins are usual in cirrhosis. Much evidence supports the prognostic role of hypolipidemia in cirrhotic patients. In particular, hypocholesterolemia represents an independent predictor of survival in cirrhosis. In cirrhotic patients, lipoprotein impairment is associated with several complications: infections, malnutrition, adrenal function, and spur cell anemia. Alterations of liver function are associated with modifications of circulating lipids. Decreased levels of lipoproteins significantly impact the survival of cirrhotic patients and play an important role in the pathogenesis of some cirrhosis-related complications.

Association between visceral obesity and hepatitis C infection stratified by gender: a cross-sectional study in Taiwan

OBJECTIVES

The global prevalence of hepatitis C virus (HCV) is approximately 2%-3%, and the prevalence of the positive anti-HCV antibody has been increasing. Several studies have evaluated regional adipose tissue distribution and metabolism over the past decades. However, no study has focused on the gender difference in visceral obesity among patients with HCV infection.

DESIGN

Retrospective cross-sectional study.

SETTING

We reviewed the medical records of patients who visited a hospital in Southern Taiwan for health check-up from 2013 to 2015.

PARTICIPANTS

A total of 1267 medical records were collected. We compared patient characteristics, variables related to metabolic risk and body composition measured using bioelectrical impedance analysis between the groups. Regression models were built to adjust for possible confounding factors.

RESULTS

The prevalence rate of the positive anti-HCV antibody was 8.8% in the study population, 8.5% in men and 9.2% in women. Men with HCV infection tended to be older and have lower total cholesterol levels and higher alanine aminotransferase (ALT) levels (p<0.001). Women with HCV infection tended to be older and have higher levels of fasting glucose and ALT (p<0.001). After adjusting for confounding factors, body fat percentage, fat-free mass/body weight (BW) and muscle mass/BW were found to be the independent determinants of visceral obesity in patients without HCV infection (p<0.001). However, the trend was not such obvious in patients with HCV infection, though still statistically significant (p<0.05). Furthermore, the trend was less significant in men with HCV infection.

CONCLUSIONS

The findings suggested that HCV modulates host lipid metabolism and distribution to some extent, and a gender difference was also noted.

Association of Serum Lipids with Hepatic Steatosis, Stage of Liver Fibrosis and Viral Load in Chronic Hepatitis C

INTRODUCTION

Hepatitis C Virus (HCV) relies on host lipids for its life cycle contributing to lipid abnormalities and hepatic steatosis. Disease progression is influenced by viral factors interacting with host immune and metabolic pathways. The significance of serum lipids for Chronic Hepatitis C (CHC) assessment is not clearly established yet.

AIM

Our aim was to investigate serum lipids' association with stage of liver fibrosis, steatosis and genotypes in patients with CHC.

MATERIALS AND METHODS

A total of 112 CHC patients (54 male, 58 female, aged 48.6±13.7 years) were studied - 98 genotype 1 (G1) and 14 genotype 3 (G3). Liver cirrhosis (F4) was diagnosed in 31 cases. Steatosis was present in 75 of all patients on ultrasound. Liver biopsy was done in 65 patients and histology showed steatosis in 28, stages of fibrosis (F1-F3) in 56 and F4 in 9 patients (METAVIR). Laboratory panel included complete blood count, liver tests and serum lipid levels (mmol/l) with Friedewald equation estimations. Indirect noninvasive fibrosis scores FIB-4, Aspartate aminotransferase to Platelet Ratio Index (APRI) and Forns index were calculated. HCV RNA was quantified by RT-PCR. Statistical analysis included Spearman's rho, Mann-Whitney U test, Receiver Operating Characteristic (ROC) curve.

RESULTS

Total Cholesterol (TCh) (p=0.002) and Low-Density Lipoprotein (LDL) (p=0.003) in G1 patients were higher when steatosis was present. TCh (p<0.001), High-Density Lipoprotein (HDL) (p=0.018) and LDL (p=0.003) were lower in G1 F4 compared with F1-F3 patients. Triglyceride (TG) levels correlated with FIB-4 (r=0.364, p=0.029), APRI (r=0.333, p=0.047) and Forns index (r=0.423, p=0.010) in G1 patients without steatosis. TG to LDL ratio (TG/LDL) (p=0.001) was higher in F4 than in F1-F3 patients. TG/LDL ratio predicted the presence of F4 in G1 patients without steatosis by an area under the ROC curve 0.900 (p<0.001). TG/LDL ratio > 0.52 was highly specific for F4 without steatosis. Specificity dropped to 76% when steatosis was present. TG/LDL < 0.32 negatively predicted liver cirrhosis. HCV RNA correlated with TG levels (r=0.330, p=0.009) in G1 patients with steatosis and with histological percent of fatty hepatocytes (r=0.585, p=0.028) in G3 patients.

CONCLUSION

Lipid levels in CHC G1 patients depend on the presence of steatosis and cirrhosis. HCV RNA is associated with TG levels in G1 patients with steatosis, but not in G3 patients. In cirrhotic CHC G1 patients cholesterol is low with relatively increased TG. TG/LDL ratio is a potential marker of liver cirrhosis in CHC G1 patients.

A Comparative Analysis of Serum Lipids in Patients with Chronic Hepatitis C, Nonalcoholic Fatty Liver Disease and Healthy Controls

Serum lipids abnormalities are widespread among patients with chronic hepatitis C (CHC), but the impact of concomitant hepatic steatosis [steatosis, nonalcoholic steatosis (NAS)], as well as distinctions between it and nonalcoholic fatty liver disease (NAFLD) are not well established yet. The aim of the study was to assess and compare the serum lipids in patients with genotype 1 CHC with and without steatosis, those with NAFLD, and healthy controls (HC). A total of 1010 subjects were included in this study: 366 CHC genotype 1 patients with steatosis (n = 227) and without steatosis (n = 139), 403 NAFLD patients, and 241 HC without fatty liver or other disease, matched for age and gender. Serum lipids, body mass index (BMI), components of metabolic syndrome (MS), and serum insulin levels were evaluated. In addition serum lipoprotein (a) [Lp(a)] levels were studied in 112 CHC and 80 NAFLD patients. The mean levels of total cholesterol, LDL-cholesterol and triglycerides (Tg) were higher and the mean levels of HDL-cholesterol were lower in all patients with steatosis (CHC and NAFLD) than in CHC cases without steatosis (p < 0.05 and p = 0.001, resp.). Higher prevalence and severity of lipid abnormalities, including Lp(a), were observed in patients with NAFLD than in those with CHC (p < 0.001). No difference was found between CHC patients without steatosis and HC. Higher prevalence and grade of glucose metabolic abnormalities were also observed in patients with NAFLD and CHC with steatosis than in cases without steatosis (p < 0.05 and p = 0.001, resp.). Lipid and glucose metabolic abnormalities in patients with CHC were dependent on steatosis. CHC with steatosis and NAFLD were associated with insulin resistant type dyslipidemia, with total cholesterol and LDL-cholesterol being generally lower in CHC.

Identification of a novel human long non-coding RNA that regulates hepatic lipid metabolism by inhibiting SREBP-1c

Sterol regulatory element binding proteins (SREBPs) are master regulators of hepatic lipid homeostasis. Aberrant expression of SREBPs frequently leads to lipid metabolism dysregulation. Long non-coding RNAs (lncRNAs) have been identified with diverse biological functions, but the effects of lncRNAs on lipid metabolism are rarely reported. Here, we identified a novel human specific lncRNA, lncHR1, as a negative regulator of SREBP-1c expression. Overexpression of lncHR1 inhibited expression of SREBP-1c and fatty acid synthase (FAS) and then repressed oleic acid-induced hepatic cell triglyceride (TG) and lipid droplet (LD) accumulation. In vivo, the data of established transgenic animals showed that mice with lncHR1 expression had less hepatic expression of SREBP-1c, FAS, Acetyl-CoA carboxylase α (ACCα), and less hepatic and plasma TG after being fed a high-fat diet. Therefore, we report a novel lncRNA which can decrease lipid metabolism by repressing SREBP-1c gene expression.

Effect of antiviral therapy for HCV on lipid levels

BACKGROUND

HCV has complex interactions with human lipid metabolism leading to down regulation of cholesterol levels. Interferon (IFN) therapy has been shown to decrease cholesterol even further. With the availability of second-generation direct-acting antiviral agents (DAA) the effect of suppressing and eliminating HCV on lipid metabolism warrants reevaluation.

METHODS

Prospective German multicentre cohort on HCV- and HIV-HCV-infected patients treated with direct-antiviral agents (GECCO). Lipids were assessed at baseline, during and after therapy. Wilcoxon test corrected for multiple testing was used.

RESULTS

For the analysis, 520 patients with chronic hepatitis C were available. Patients with chronic hepatitis C were treated as follows: sofosbuvir (SOF)/pegylated IFN (PEG-IFN)/ribavirin (RBV; HCV=34, HIV-HCV=36), SOF/RBV (HCV=47, HIV-HCV=16), SOF/simeprevir (HCV=9, HCV-HIV=2), SOF/daclatasvir +/- RBV (HCV=27, HIV-HCV=47), SOF/ledipasvir +/- RBV (HCV=147, HCV-HIV=100) and ombitasvir/paritaprevir/ritonavir +/- dasabuvir +/- RBV (2D, HCV=2, HCV-HIV=6; 3D, HCV=39, HCV-HIV=8). On treatment there was a statistically significant increase in total cholesterol for any IFN-free DAA regimen, which was maintained after end of therapy. Changes of total cholesterol were driven by changes in low-density lipoprotein cholesterol, whereas high-density lipoprotein cholesterol remained unchanged. In contrast, total cholesterol decreased on SOF/PEG-IFN/RBV and increased after end of therapy above baseline levels. Triglycerides increased during treatment with SOF/PEG-IFN/RBV, but not on DAA-only regimens.

CONCLUSIONS

Suppressing and eliminating HCV with IFN-free DAA regimens increased cholesterol levels, but had no effect on triglycerides. In contrast IFN-based therapy decreased cholesterol and increased triglycerides during treatment and led to increases in cholesterol after achieving sustained virological response.

Hepatitis C virus infection: Are there still specific problems with genotype 3?

Hepatitis C virus (HCV) infection is one of the most common causes of chronic liver disease and the main indication for liver transplantation worldwide. As promising specific treatments have been introduced for genotype 1, clinicians and researchers are now focusing on patients infected by non-genotype 1 HCV, particularly genotype 3. Indeed, in the golden era of direct-acting antiviral drugs, genotype 3 infections are no longer considered as easy to treat and are associated with higher risk of developing severe liver injuries, such as cirrhosis and hepatocellular carcinoma. Moreover, HCV genotype 3 accounts for 40% of all HCV infections in Asia and is the most frequent genotype among HCV-positive injecting drug users in several countries. Here, we review recent data on HCV genotype 3 infection/treatment, including clinical aspects and the underlying genotype-specific molecular mechanisms.

Changes in circulating lipids level over time after acquiring HCV infection: results from ERCHIVES

BACKGROUND

Changes in lipid levels over time after acquiring HCV infection, and how they differ from HCV-uninfected persons are unknown.

METHODS

We used ERCHIVES to identify those with a known HCV seroconversion window and persistently negative controls. We excluded subjects with HIV and hepatitis B and those who received lipid lowering agents. Total Cholesterol (TC), low-density lipoproteins (LDL), high-density lipoproteins (HDL), triglycerides (TG) and non-HDL cholesterol were retrieved at yearly intervals and plotted over time.

RESULTS

Among 1,270 HCV+ and 5,070 HCV- subjects, median age [IQR] was 47[37,53] for HCV+ and 52[47,57] for the HCV- group; 69% were White and 91% were males in each group. Mean BMI [SD] was 26.94[6.73] in the HCV+ and 28.15 [5.98] in the HCV- group (P < 0.001). Over a 10-year follow-up period among HCV+ persons, TC decreased by (mean (SD) mg/dL) 12.06(36.95), LDL by 9.22(31.44), TG by 13.58(87.01) and non-HDL-C by 12.55(35.14). Among HCV- persons, TC cholesterol decreased by 4.15(31.21), LDL by 4.16(26.51); TG by 4.42(82.34) and non-HDL-C by 5.78(30.17).

CONCLUSIONS

After HCV acquisition, TC, LDL, TG and non-HDL-C progressively decline over time independent of BMI and liver fibrosis. Consequences of lipid changes and the need and optimal timing of lipid lowering therapy in HCV+ persons require further study.

Impact of Chronic Hepatitis C Virus Genotype 1b Infection on Triglyceride Concentration in Serum Lipoprotein Fractions

Reduced low-density lipoprotein (LDL) cholesterol level is a characteristic feature of dyslipidemia in chronic hepatitis C virus (HCV) infection. However, abnormality in serum triglyceride (TG) has not been fully investigated. To clarify the impact of HCV genotype 1b (G1b) infection and advanced fibrosis on serum TG profiles, TG concentrations in lipoprotein fractions were examined in fasting sera from 185 subjects with active or cleared HCV infection by high-performance liquid chromatography. Serum lipoproteins were fractionated into four classes: chylomicron, very low-density lipoprotein (VLDL), LDL, and high-density lipoprotein (HDL). Then, the significance of HCV G1b infection on TG levels in each lipoprotein fraction was determined using multiple regression models. We found that active HCV G1b infection was positively associated with high HDL-TG levels and low VLDL-TG levels, independent of other factors included in the regression model. In VLDL sub-fractions, active HCV infection was only found to be associated with low levels of large VLDL-TG. Similarly, advanced liver fibrosis in chronic HCV G1b infection was associated with high levels of LDL-TG, HDL-TG, and small VLDL-TG, independent of other clinical factors. These findings indicate that active HCV G1b infection and advanced fibrosis are closely associated with abnormal serum TG profiles.

Epigenetic harnessing of HCV via modulating the lipid droplet-protein, TIP47, in HCV cell models

This study aimed at identifying potential microRNAs that modulate hepatic lipid droplets (LD) through targeting the Tail interacting protein of 47 kDa (TIP47) in HCV infection. Bioinformatics analysis revealed that miR-148a and miR-30a potentially target TIP47. Expression profiling showed that both microRNAs were downregulated, while TIP47 was upregulated in liver biopsies of HCV-infected patients. Forcing the expression of both microRNAs in JFH-I infected, oleic acid-treated Huh7 cells, significantly suppressed TIP47 expression and reduced cellular LDs with marked decrease in viral RNA. This study shows that miR-148a and miR-30a, regulate TIP47 expression and LDs in HCV infected cells.

Recombinant hepatitis C virus-envelope protein 2 interactions with low-density lipoprotein/CD81 receptors

Hepatitis C virus (HCV) envelope protein 2 (E2) is involved in viral binding to host cells. The aim of this work was to produce recombinant E2B and E2Y HCV proteins in Escherichia coli and Pichia pastoris, respectively, and to study their interactions with low-density lipoprotein receptor (LDLr) and CD81 in human umbilical vein endothelial cells (HUVEC) and the ECV304 bladder carcinoma cell line. To investigate the effects of human LDL and differences in protein structure (glycosylated or not) on binding efficiency, the recombinant proteins were either associated or not associated with lipoproteins before being assayed. The immunoreactivity of the recombinant proteins was analysed using pooled serum samples that were either positive or negative for hepatitis C. The cells were immunophenotyped by LDLr and CD81 using flow cytometry. Binding and binding inhibition assays were performed in the presence of LDL, foetal bovine serum (FCS) and specific antibodies. The results revealed that binding was reduced in the absence of FCS, but that the addition of human LDL rescued and increased binding capacity. In HUVEC cells, the use of antibodies to block LDLr led to a significant reduction in the binding of E2B and E2Y. CD81 antibodies did not affect E2B and E2Y binding. In ECV304 cells, blocking LDLr and CD81 produced similar effects, but they were not as marked as those that were observed in HUVEC cells. In conclusion, recombinant HCV E2 is dependent on LDL for its ability to bind to LDLr in HUVEC and ECV304 cells. These findings are relevant because E2 acts to anchor HCV to host cells; therefore, high blood levels of LDL could enhance viral infectivity in chronic hepatitis C patients.

Chronic hepatitis C infection is associated with insulin resistance and lipid profiles

BACKGROUND AND AIM

Chronic hepatitis C virus (HCV) infection has been suggested to be associated with non-insulin-dependent diabetes mellitus and lipid profiles. This study aimed to investigate the possible relationships of insulin resistance (IR) and lipid profiles with chronic hepatitis C (CHC) patients in Taiwan.

METHODS

We enrolled 160 hospital-based CHC patients with liver biopsy and the 480 controlled individuals without CHC and chronic hepatitis B from communities without known history of non-insulin-dependent diabetes mellitus. Fasting plasma glucose, total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TGs), alanine aminotransferase, and serum insulin levels, and homeostasis model assessment (HOMA-IR) were tested.

RESULTS

When comparing factors between CHC patients, and sex- and age-matched controls who had no HCV infection, patients with HCV infection had a significantly higher alanine aminotransferase level, fasting plasma glucose level, insulin level, and HOMA-IR (P < 0.001, P = 0.023, P = 0.017, and P = 0.011, respectively), and significantly lower TG level (P = 0.023), total cholesterol, and HDL-C and LDL-C levels (all P < 0.001) than 480 controls. In multivariate logistic regression analyses, a low total cholesterol, a low TGs, and a high HOMA-IR are independent factors significantly associated with chronic HCV infection. In the 160 CHC patients (41 patients with high HOMA-IR [> 2.5]), a high body mass index, TGs, and HCV RNA level are independent factors significantly associated with high HOMA-IR in multivariate logistic analyses.

CONCLUSIONS

Chronic HCV infection was associated with metabolic characteristics including IR and lipid profile. IR was also associated with virological characteristics.

Phosphatidylinositol 4,5-bisphosphate is an HCV NS5A ligand and mediates replication of the viral genome

BACKGROUND & AIMS

Phosphoinositides (PIs) bind and regulate localization of proteins via a variety of structural motifs. PI 4,5-bisphosphate (PI[4,5]P2) interacts with and modulates the function of several proteins involved in intracellular vesicular membrane trafficking. We investigated interactions between PI(4,5)P2 and hepatitis C virus (HCV) nonstructural protein 5A (NS5A) and effects on the viral life cycle.

METHODS

We used a combination of quartz crystal microbalance, circular dichroism, molecular genetics, and immunofluorescence to study specific binding of PI(4,5)P2 by the HCV NS5A protein. We evaluated the effects of PI(4,5)P2 on the function of NS5A by expressing wild-type or mutant forms of Bart79I or FL-J6/JFH-5'C19Rluc2AUbi21 RNA in Huh7 cells. We also studied the effects of strategies designed to inhibit PI(4,5)P2 on HCV replication in these cells.

RESULTS

The N-terminal amphipathic helix of NS5A bound specifically to PI(4,5)P2, inducing a conformational change that stabilized the interaction between NS5A and TBC1D20, which is required for HCV replication. A pair of positively charged residues within the amphipathic helix (the basic amino acid PI(4,5)P2 pincer domain) was required for PI(4,5)P2 binding and replication of the HCV-RNA genome. A similar motif was found to be conserved across all HCV isolates, as well as amphipathic helices of many pathogens and apolipoproteins.

CONCLUSIONS

PI(4,5)P2 binds to HCV NS5A to promote replication of the viral RNA genome in hepatocytes. Strategies to disrupt this interaction might be developed to inhibit replication of HCV and other viruses.

Impact of lipids and lipoproteins on hepatitis C virus infection and virus neutralization

Hepatitis C virus (HCV) infections represent a major global health problem. End-stage liver disease caused by chronic HCV infection is a major indication for liver transplantation. However, after transplantation the engrafted liver inevitably becomes infected by the circulating virus. Direct acting antivirals are not yet approved for use in liver transplant patients, and limited efficacy and severe side effects hamper the use of pegylated interferon combined with ribavirin in a post-transplant setting. Therefore, alternative therapeutic options need to be explored. Viral entry represents an attractive target for such therapeutic intervention. Understanding the mechanisms of viral entry is essential to define the viral and cellular factors involved. The HCV life cycle is dependent of and associated with lipoprotein physiology and the presence of lipoproteins has been correlated with altered antiviral efficacy of entry inhibitors. In this review, we summarise the current knowledge on how lipoprotein physiology influences the HCV life cycle. We focus especially on the influence of lipoproteins on antibodies that target HCV envelope proteins or antibodies that target the cellular receptors of the virus. This information can be particularly relevant for the prevention of HCV re-infection after liver transplantation.

The effect of the severity of liver cirrhosis on the level of lipids and lipoproteins

The effect of severity of liver cirrhosis, an alcoholic and non-alcoholic genesis, on the results of serum lipids and lipoproteins was evaluated. Serum cholesterol, triglycerides, high-density lipoprotein cholesterol (HDL-Ch), and low-density lipoprotein cholesterol (LDL-Ch) were measured in the sera of 59 patients suffering from alcoholic cirrhosis and 34 patients with non-alcoholic cirrhosis. The level of serum triglycerides depends on the severity of liver damage in alcoholic liver cirrhosis, being the highest in Child-Pugh score B. The severity of liver damage significantly affects the HDL-Ch and LDL-Ch levels in cirrhosis of non-alcoholic origin, reaching the highest value for LDL-Ch and the lowest for HDL-Ch in score C. It should not be generalized that the levels of lipids and lipoproteins in liver cirrhosis progressively diminished with the deterioration of liver function. The serum HDL-Ch and LDL-Ch may be considered as markers of severity of liver damage in non-alcoholic cirrhosis, but the triglycerides only in disease of alcoholic origin.

Hepatitis C virus infection mediates cholesteryl ester synthesis to facilitate infectious particle production

Cholesterol is a critical component of the hepatitis C virus (HCV) life cycle, as demonstrated by its accumulation within infected hepatocytes and lipoviral particles. To cope with excess cholesterol, hepatic enzymes ACAT1 and ACAT2 produce cholesteryl esters (CEs), which are destined for storage in lipid droplets or for secretion as apolipoproteins. Here we demonstrate in vitro that cholesterol accumulation following HCV infection induces upregulation of the ACAT genes and increases CE synthesis. Analysis of human liver biopsy tissue showed increased ACAT2 mRNA expression in liver infected with HCV genotype 3, compared with genotype 1. Inhibiting cholesterol esterification using the potent ACAT inhibitor TMP-153 significantly reduced production of infectious virus, but did not inhibit virus RNA replication. Density gradient analysis showed that TMP-153 treatment caused a significant increase in lipoviral particle density, suggesting reduced lipidation. These data suggest that cholesterol accumulation following HCV infection stimulates the production of CE, a major component of lipoviral particles. Inhibition of CE synthesis reduces HCV particle density and infectivity, suggesting that CEs are required for optimal infection of hepatocytes.

Eradicating hepatitis C virus ameliorates insulin resistance without change in adipose depots

Chronic hepatitis C (CHC) is associated with lipid-related changes and insulin resistance; the latter predicts response to antiviral therapy, liver disease progression and the risk of diabetes. We sought to determine whether insulin sensitivity improves following CHC viral eradication after antiviral therapy and whether this is accompanied by changes in fat depots or adipokine levels. We compared 8 normoglycaemic men with CHC (genotype 1 or 3) before and at least 6 months post viral eradication and 15 hepatitis C antibody negative controls using an intravenous glucose tolerance test and two-step hyperinsulinaemic-euglycaemic clamp with [6,6-(2) H2 ] glucose to assess peripheral and hepatic insulin sensitivity. Magnetic resonance imaging and spectroscopy quantified abdominal fat compartments, liver and intramyocellular lipid. Peripheral insulin sensitivity improved (glucose infusion rate during high-dose insulin increased from 10.1 ± 1.6 to 12 ± 2.1 mg/kg/min/, P = 0.025), with no change in hepatic insulin response following successful viral eradication, without any accompanying change in muscle, liver or abdominal fat depots. There was corresponding improvement in incremental glycaemic response to intravenous glucose (pretreatment: 62.1 ± 8.3 vs post-treatment: 56.1 ± 8.5 mm, P = 0.008). Insulin sensitivity after viral clearance was comparable to matched controls without CHC. Post therapy, liver enzyme levels decreased but, interestingly, levels of glucagon, fatty acid-binding protein and lipocalin-2 remained elevated. Eradication of the hepatitis C virus improves insulin sensitivity without alteration in fat depots, adipokine or glucagon levels, consistent with a direct link of the virus with insulin resistance.

Are statins a viable option for the treatment of infections with the hepatitis C virus?

Statins are 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors that are widely used for the treatment of hypercholesterolemia. Besides their cholesterol-lowering effect, statins have been reported to have antiviral activity against a variety of viruses, including hepatitis C virus (HCV). Several statins inhibit the in vitro replication of subgenomic HCV replicons and also suppress in vitro RNA replication of infectious HCV. The precise mechanism of the anti-HCV activity of statins has not yet been defined. Recent studies suggest that the antiviral effect may result from the inhibition of geranylgeranylation of cellular proteins, rather than the inhibition of cholesterol synthesis. Despite the antiviral effect observed in vitro, statin monotherapy seems to be insufficient for the treatment of chronic HCV infection. However, several prospective and retrospective studies have demonstrated that the addition of statins to IFN-α and ribavirin therapy increases SVR, RVR, and EVR rates without the occurrence of additional adverse events. These clinical data, together with the excellent safety profile and low cost, suggest that statins may play a role in HCV therapy until more potent and safe direct-acting antivirals become available. This article forms part of a symposium in Antiviral Research on "Hepatitis C: next steps toward global eradication."

Association of IFNL3 rs12979860 and rs8099917 with biochemical predictors of interferon responsiveness in chronic hepatitis C virus infection

BACKGROUND & AIMS

Genetic variations near the interferon lambda 3 gene (IFNL3, IL28B) are the most powerful predictors for sustained virologic response (SVR) in patients with chronic hepatitis C virus (HCV) infection, compared to other biochemical or histological baseline parameters. We evaluated whether the interplay of both IFNL3 polymorphisms rs12979860 and rs8099917 together with non-genetic clinical factors contributes to the predictive role of these genetic variants.

METHODS

The cohort comprised 1,402 patients of European descent with chronic HCV type 1 infection. 1,298 patients received interferon-based antiviral therapy, and 719 (55%) achieved SVR. The IFNL3 polymorphisms were genotyped by polymerase chain reaction and melting curve analysis.

RESULTS

A significant correlation was found between the IFNL3 polymorphisms and biochemical as well as virologic predictors of treatment outcome such as ALT, GGT, cholesterol, and HCV RNA levels. In multivariate regression analysis, IFLN3 SNPs, HCV RNA levels, and the GGT/ALT ratio were independent predictors of SVR. Dependent on the GGT/ALT ratio and on the HCV RNA concentration, significant variations in the likelihood for achieving SVR were observed in both, carriers of the responder as well as non-responder alleles.

CONCLUSIONS

Our data support a clear association between IFNL3 genotypes and baseline parameters known to impact interferon responsiveness. Improved treatment outcome prediction was achieved when these predictors were considered in combination with the IFNL3 genotype.

Effects of metabolic syndrome on fibrosis in chronic viral hepatitis

Background/Aims

Metabolic syndrome, comprising diabetes, hypertension, central obesity, and dyslipidemia, is increasingly prevalent worldwide. We aimed to study the relationship between metabolic syndrome and the risk of liver fibrosis in patients with chronic hepatitis B (CHB) and chronic hepatitis C (CHC).

Methods

In total, 954 patients (CHB, 850; CHC, 104 patients) with liver biopsy were included in the retrospective analysis. Extensive clinical and histological data were available. Metabolic syndrome was defined using the International Diabetes Federation definition of metabolic syndrome, 2006 criteria. Histological lesions were evaluated according to the histology activity index system.

Results

Metabolic syndrome was present in 6% of patients and significantly more prevalent in patients with CHC than in patients with CHB (5% vs 13%, p<0.001). Patients with metabolic syndrome were older among patients with CHB and patients with CHC, and, as expected, were mainly overweight or obese. Fibrosis was significantly more severe in patients with metabolic syndrome than in those without, regardless of whether they had CHB and CHC (CHB, 3.3±2.1 vs 2.4±1.3, p=0.025; CHC, 2.6±1.5 vs 1.3±0.7, p=0.006). Liver fibrosis (stages 3 to 4) was independently associated with increased age, higher transaminase level and metabolic syndrome (odds ratio, 2.421; p=0.017).

Conclusions

Metabolic syndrome is associated independently with severe fibrosis in patients with chronic viral hepatitis B and C.

A nationwide seroepidemiology of hepatitis C virus infection in South Korea

BACKGROUND & AIMS

The aim of this study was to reveal nationwide seroprevalence of HCV infection in South Korea by a large-scale survey.

METHODS

From January to December 2009, a total of 291 314 adults underwent health check-up in 29 centres nationwide. The data concerning anti-HCV antibody and biochemical tests were obtained from all participants. Among subjects with positive anti-HCV, such data as HCV RNA, genotypes and treatment detail were additionally analysed.

RESULTS

Using an estimated 2009 population of Korea, the age, sex and area-adjusted anti-HCV positive rate was 0.78%. Anti-HCV prevalence in female patients (0.83%) was higher than that in male patients (0.75%). Gradual increase in anti-HCV positivity was observed, from 0.34% in those aged 20-29 years to 2.31% in those >70 years. The age- and sex-adjusted anti-HCV prevalence varied in different areas, being higher in Busan and Jeonnam (1.53-2.07%), mid-level in Seoul and surrounding districts (0.50-0.61%) and lower in Jeju (0.23%). The comparative analysis of laboratory variables between anti-HCV (+) and anti-HCV (-) group revealed significantly higher levels of alanine aminotransferase and lower levels of serum lipids in anti-HCV (+) group. Among 1 718 anti-HCV positive subjects, serum HCV RNA was measured only in 478 people, of whom 268 (56.1%) patients had detectable HCV RNA in serum. Among 50 patients for whom assessment of response to antiviral therapy was feasible, overall sustained virological response was achieved in 84% of patients.

CONCLUSION

The prevalence of HCV infection is low in South Korea. Studies to analyse risk factors are warranted to reduce HCV infection.

Activation of TGF-β1 promoter by hepatitis C virus-induced AP-1 and Sp1: role of TGF-β1 in hepatic stellate cell activation and invasion

Our previous studies have shown the induction and maturation of transforming growth factor-beta 1 (TGF-β1) in HCV-infected human hepatoma cells. In this study, we have investigated the molecular mechanism of TGF-β1 gene expression in response to HCV infection. We demonstrate that HCV-induced transcription factors AP-1, Sp1, NF-κB and STAT-3 are involved in TGF-β1 gene expression. Using chromatin immunoprecipitation (ChIP) assay, we further show that AP-1 and Sp1 interact with TGF-b1 promoter in vivo in HCV-infected cells. In addition, we demonstrate that HCV-induced TGF-β1 gene expression is mediated by the activation of cellular kinases such as p38 MAPK, Src, JNK, and MEK1/2. Next, we determined the role of secreted bioactive TGF-β1 in human hepatic stellate cells (HSCs) activation and invasion. Using siRNA approach, we show that HCV-induced bioactive TGF-β1 is critical for the induction of alpha smooth muscle actin (α-SMA) and type 1 collagen, the markers of HSCs activation and proliferation. We further demonstrate the potential role of HCV-induced bioactive TGF-β1 in HSCs invasion/cell migration using a transwell Boyden chamber. Our results also suggest the role of HCV-induced TGF-β1 in HCV replication and release. Collectively, these observations provide insight into the mechanism of TGF-β1 promoter activation, as well as HSCs activation and invasion, which likely manifests in liver fibrosis associated with HCV infection.

Hepatitis C virus diversity and hepatic steatosis

Hepatitis C virus (HCV) infection is closely associated with lipid metabolism defects throughout the viral lifecycle, with hepatic steatosis frequently observed in patients with chronic HCV infection. Hepatic steatosis is most common in patients infected with genotype 3 viruses, possibly due to direct effects of genotype 3 viral proteins. Hepatic steatosis in patients infected with other genotypes is thought to be mostly due to changes in host metabolism, involving insulin resistance in particular. Specific effects of the HCV genotype 3 core proteins have been observed in cellular models in vitro: mechanisms linked with a decrease in microsomal triglyceride transfer protein activity, decreases in the levels of peroxisome proliferator-activating receptors, increases in the levels of sterol regulatory element-binding proteins, and phosphatase and tensin homologue downregulation. Functional differences between the core proteins of genotype 3 viruses and viruses of other genotypes may reflect differences in amino acid sequences. However, bioclinical studies have failed to identify specific 'steatogenic' sequences in HCV isolates from patients with hepatic steatosis. It is therefore difficult to distinguish between viral and metabolic steatosis unambiguously, and host and viral factors are probably involved in both HCV genotype 3 and nongenotype 3 steatosis.