Detecting advanced liver fibrosis using ultrasound shear wave velocity measurement in the general population.

Background: Advanced fibrosis detection in the general population is an unmet need. Additionally, screening method for advanced fibrosis in the general population is not established. Thus, this study aimed to examine the use of shear wave measurement (SWM), which measures liver stiffness by ultrasound elastography as a screening tool for advanced fibrosis in health checkups that represents the general population. Methods: SWM was performed in all subjects. Magnetic resonance elastography (MRE) was performed in those with SWM shear wave velocity (Vs) ≥1.3 m/s to determinate advanced fibrosis. The diagnostic accuracy of SWM Vs for advanced fibrosis (determined by MRE of ≥3.62 kPa) was examined. This prospective study was registered with the University Hospital Medical Information Network clinical trial registry (UMIN000041609). Results: A total of 2,233 subjects were included. SWM Vs of 1.64 m/s was selected as the best threshold for advanced fibrosis. Using the threshold of SWM Vs at ≥1.64 m/s, subjects were narrowed down to 1.7%, and sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for advanced fibrosis were 53.3%, 92.4%, 47.1%, and 94.0%, respectively, among these subjects. The multivariable analysis, after adjusting the age, sex, body mass index (BMI), hypertension, diabetes mellitus (DM), dyslipidemia, and alcohol use, revealed an SWM Vs of ≥1.64 m/s as the significant factor for advanced fibrosis with an odds ratio (95% confidence interval) of 14.5 (3.4-62; P<0.001). Conclusions: SWM has high diagnostic accuracy for advanced fibrosis (PPV 47.1%) and may be used as a screening tool for liver fibrosis in the general population.

Liver fibrosis and fatty liver as independent risk factors for cardiovascular disease.

BACKGROUND AND AIM: The association between liver fibrosis, fatty liver, and cardiovascular disease (CVD) risk is unknown. Hence, this study aimed to investigate the association of liver fibrosis and fatty liver with CVD risk independent of already known CVD risk comorbidities. METHODS: This is a prospective study registered with the University Hospital Medical Information Network clinical trial registry (UMIN000036175). Liver fibrosis was assessed by serum fibrosis markers including FIB-4, nonalcoholic fatty liver disease fibrosis score (NFS), and Wisteria floribunda agglutinin-positive Mac-2 binding protein (WFA+ -M2BP), whereas fatty liver was diagnosed by ultrasonography. CVD risk was evaluated using the Framingham risk score (FRS), and a high CVD risk was defined as an FRS ≥ 20%. RESULTS: A total of 3512 subjects were enrolled, and high CVD risk (FRS ≥ 20%) was observed in 17.5%. Advanced fibrosis (FIB-4 ≥ 2.67, NFS ≥ 0.675, and WFA+ -M2BP ≥ 1.0) and the presence of fatty liver were significantly associated with high CVD risk independent of diabetes mellitus, dyslipidemia, and hypertension. When subjects were stratified by liver fibrosis and fatty liver, subjects with advanced fibrosis and fatty liver have the highest odds for high CVD risk (odds ratio [OR]: 5.90-35.6), followed by subjects with advanced fibrosis and without fatty liver (OR: 2.53-9.62) using subjects without advanced fibrosis and fatty liver as a reference. CONCLUSIONS: Liver fibrosis and fatty liver were associated with CVD risk independent of already known CVD risk comorbidities. The assessment of liver fibrosis and fatty liver may be useful to identify high CVD risk subjects.

Wisteria floribunda Agglutinin-Positive Mac-2 Binding Protein as a Screening Tool for Significant Liver Fibrosis in Health Checkup.

Chronic liver disease is generally widespread, and a test for screening fibrotic subjects in a large population is needed. The ability of Wisteria floribunda agglutinin-positive mac-2 binding protein (WFA+-M2BP) to detect significant fibrosis was investigated in health checkup subjects in this research. Of 2021 health checkup subjects enrolled in this prospective cross-sectional study, those with WFA+-M2BP ≥ 1.0 were defined as high risk. Liver fibrosis was evaluated using magnetic resonance elastography (MRE) in subjects with high risk. The primary outcome was the positive predictive value (PPV) of WFA+-M2BP for significant fibrosis (liver stiffness ≥ 2.97 kPa by MRE). This trial was registered with the UMIN clinical trial registry, UMIN000036175. WFA+-M2BP ≥ 1.0 was observed in 5.3% of the 2021 subjects. The PPV for significant fibrosis with the threshold of WFA+-M2BP at ≥1.0, ≥1.1, ≥1.2, ≥1.3, ≥1.4, and ≥1.5 was 29.2%, 36.4%, 43.5%, 42.9%, 62.5%, and 71.4%, respectively. A WFA+-M2BP of 1.2 was selected as the optimal threshold for significant fibrosis among high-risk subjects, and the PPV, negative predictive value, sensitivity, and specificity for significant fibrosis were 43.5%, 84.0%, 71.4%, and 61.8%, respectively. WFA+-M2BP ≥ 1.2 was significantly associated with significant fibrosis, with an odds ratio (OR) of 4.04 (95% confidence interval (CI): 1.1-16, p = 0.04), but not FIB-4 ≥ 2.67 (OR: 2.40, 95%CI: 0.7-8.6, p-value = 0.2). In conclusion, WFA+-M2BP is associated with significant fibrosis and could narrow down potential subjects with liver fibrosis. The strategy of narrowing down fibrosis subjects using WFA+-M2BP may be used to screen for fibrotic subjects in a large population.

Resistance-Associated NS5A Variants of Hepatitis C Virus Are Susceptible to Interferon-Based Therapy.

BACKGROUND & AIMS: The presence of resistance-associated variants (RAVs) of hepatitis C virus (HCV) attenuates the efficacy of direct acting antivirals (DAAs). The objective of this study was to characterize the susceptibility of RAVs to interferon-based therapy. METHODS: Direct and deep sequencing were performed to detect Y93H RAV in the NS5A region. Twenty nine genotype 1b patients with detectable RAV at baseline were treated by a combination of simeprevir, pegylated interferon and ribavirin. The longitudinal changes in the proportion of Y93H RAV during therapy and at breakthrough or relapse were determined. RESULTS: By direct sequencing, Y93H RAV became undetectable or decreased in proportion at an early time point during therapy (within 7 days) in 57% of patients with both the Y93H variant and wild type virus at baseline when HCV RNA was still detectable. By deep sequencing, the proportion of Y93H RAV against Y93 wild type was 52.7% (5.8%- 97.4%) at baseline which significantly decreased to 29.7% (0.16%- 98.3%) within 7 days of initiation of treatment (p = 0.023). The proportion of Y93H RAV was reduced in 21 of 29 cases (72.4%) and a marked reduction of more than 10% was observed in 14 cases (48.7%). HCV RNA reduction was significantly greater for Y93H RAV (-3.65±1.3 logIU/mL/day) than the Y93 wild type (-3.35±1.0 logIU/mL/day) (p<0.001). CONCLUSION: Y93H RAV is more susceptible to interferon-based therapy than the Y93 wild type.

Naturally occurring, resistance-associated hepatitis C virus NS5A variants are linked to interleukin-28B genotype and are sensitive to interferon-based therapy.

AIM: The presence of resistance-associated variants (RAV) may attenuate the efficacy of direct-acting antivirals (DAA) in combination therapy for hepatitis C. The aim of this study was to characterize the NS3 and NS5A regions of hepatitis C virus (HCV) in naturally occurring RAV. METHODS: The NS3 and NS5A regions of HCV were amplified by nested polymerase chain reaction and their nucleotide sequences were determined by direct sequencing in 493 genotype 1b patients naive to DAA-based therapies. The effect of baseline RAV on response to pegylated interferon and ribavirin therapy was analyzed in 65 patients after stratification by interleukin (IL)-28B genotype. RESULTS: The incidence of RAV was 7.9% in NS3 (V36I/L, 1.2%; T54S, 2.8%; Q80K/R, 3.0%; A156S, 0.2%; and D168E/T, 2.4%) and 20.2% in NS5A (L31I/M, 2.2%; and Y93H, 19.0%). The incidence in interferon experienced and naive patients was similar. The incidence of Y93H in NS5A was significantly higher in the IL-28B TT genotype (rs8099917) than non-TT (27.1% vs 9.5%, P < 0.001). The virological response to pegylated interferon plus ribavirin therapy was not affected by the presence of RAV in IL-28B TT genotype. CONCLUSION: RAV, especially Y93H in the NS5A region, were highly prevalent in DAA naive patients with genotype 1b HCV in Japan and were linked to IL-28B TT genotype. Interferon-based therapy could be an alternative for patients with RAV because these variants did not attenuate the response to that therapy. The analysis of RAV may impact the selection of the optimal treatment strategy.

Reproducibility and usability of chronic virus infection model using agent-based simulation; comparing with a mathematical model.

We created agent-based models that visually simulate conditions of chronic viral infections using two software. The results from two models were consistent, when they have same parameters during the actual simulation. The simulation results comprise a transient phase and an equilibrium phase, and unlike the mathematical model, virus count transit smoothly to the equilibrium phase without overshooting which correlates with actual biology in vivo of certain viruses. We investigated the effects caused by varying all the parameters included in concept; increasing virus lifespan, uninfected cell lifespan, uninfected cell regeneration rate, virus production count from infected cells, and infection rate had positive effects to the virus count during the equilibrium period, whereas increasing the latent period, the lifespan-shortening ratio for infected cells, and the cell cycle speed had negative effects. Virus count at the start did not influence the equilibrium conditions, but it influenced the infection development rate. The space size had no intrinsic effect on the equilibrium period, but virus count maximized when the virus moving speed was twice the space size. These agent-based simulation models reproducibly provide a visual representation of the disease, and enable a simulation that encompasses parameters those are difficult to account for in a mathematical model.

Targeting lipid metabolism in the treatment of hepatitis C virus infection.

Recently, microdomains of organelle membranes rich in sphingomyelin and cholesterol (called "lipid rafts") have been considered to act as a scaffold for the hepatitis C virus (HCV) replication complex. Using the HCV cell culture system, we investigated the effect of myriocin, a sphingomyelin synthesis inhibitor, on HCV replication. We also investigated the combined effect of myriocin with interferon (IFN) and myriocin with simvastatin. Myriocin suppressed replication of both a genotype 1b subgenomic HCV replicon (Huh7/Rep-Feo) and genotype 2a infectious HCV (JFH-1 HCV) in a dose-dependent manner (for subgenomic HCV-1b, maximum of 79% at 1000 nmol/L; for genomic HCV-2a, maximum of 40% at 1000 nmol/L). Combination treatment with myriocin and IFN or myriocin and simvastatin attenuated HCV RNA replication synergistically in Huh7/Rep-Feo cells. Our data demonstrate that the sphingomyelin synthesis inhibitor strongly suppresses replication of both the subgenomic HCV-1b replicon and the JFH-1 strain of genotype 2a infectious HCV, indicating that lipid metabolism could be a novel target for HCV therapy.

Hepatitis C virus non-structural proteins responsible for suppression of the RIG-I/Cardif-induced interferon response.

Viral infections activate cellular expression of type I interferons (IFNs). These responses are partly triggered by RIG-I and mediated by Cardif, TBK1, IKKepsilon and IRF-3. This study analysed the mechanisms of dsRNA-induced IFN responses in various cell lines that supported subgenomic hepatitis C virus (HCV) replication. Transfection of dsRNA into Huh7, HeLa and HEK293 cells induced an IFN expression response as shown by IRF-3 dimerization, whilst these responses were abolished in corresponding cell lines that expressed HCV replicons. Similarly, RIG-I-dependent activation of the IFN-stimulated response element (ISRE) was significantly suppressed by cells expressing the HCV replicon and restored in replicon-eliminated cells. Overexpression analyses of individual HCV non-structural proteins revealed that NS4B, as well as NS34A, significantly inhibited RIG-I-triggered ISRE activation. Taken together, HCV replication and protein expression substantially blocked the dsRNA-triggered, RIG-I-mediated IFN expression response and this blockade was partly mediated by HCV NS4B, as well as NS34A. These mechanisms may contribute to the clinical persistence of HCV infection and could constitute a novel antiviral therapeutic target.

Inhibition of 17alpha-hydroxylase/C17,20-lyase (CYP17) from rat testis by green tea catechins and black tea theaflavins.

In the course of screening for 17alpha-hydroxylase/C17,20-lyase inhibitors from food ingredients, the methanol soluble fraction of green tea and black tea, which were expected to be rich in catechin and theaflavin content, showed potent inhibitory activity. (-)-Epigallocathechin gallate and theaflavin 3-O-gallate with a pirogallol moiety significantly inhibited C17,20-lyase activity on IC50 values of 24.5 microM and 11.5 microM respectively. They had potent cytotoxicity against human prostate cancer LNCaP cells (IC50=28.1 microM and 37.4 microM).