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Background: Hepatic encephalopathy is a major complication of cirrhosis and is associated with a poor prognosis. Objective: To identify mutations in the gene sequence for glutaminase in humans that could be responsible for the development of hepatic encephalopathy in patients with cirrhosis. Design: Cohort study. Setting: Outpatient clinics in 6 Spanish hospitals. Patients: 109 consecutive patients with cirrhosis in the estimation cohort, 177 patients in the validation cohort, and 107 healthy control participants. Measurements: Patients were followed every 3 or 6 months until the development of hepatic encephalopathy or liver transplantation, death, or the end of the study. Results: The genetic analyses showed that glutaminase TACC and CACC haplotypes were linked to the risk for overt hepatic encephalopathy. Mutation scanning of the glutaminase gene identified a section in the promoter region where base pairs were repeated (a microsatellite). Over a mean follow-up of 29.6 months, hepatic encephalopathy occurred in 28 patients (25.7%) in the estimation cohort. Multivariable Cox models were used to determine the following independent predictors: Child-Turcotte-Pugh stage (hazard ratio [HR], 1.6 [95% CI, 1.29 to 1.98]; P = 0.001), minimal hepatic encephalopathy (HR, 3.17 [CI, 1.42 to 7.09]; P = 0.006), and having 2 long alleles of the microsatellite (HR, 3.12 [CI, 1.39 to 7.02]; P = 0.006). The association between 2 long alleles of the microsatellite and overt hepatic encephalopathy was confirmed in a validation cohort (HR, 2.1 [CI, 1.17 to 3.79]; P = 0.012). Functional studies showed higher luciferase activity in cells transfected with the long form of the microsatellite, which suggests that the long microsatellite enhances glutaminase transcriptional activity. Limitation: Other genes and allelic variants might be involved in the clinical expression of hepatic encephalopathy. Conclusion: This study identifies a genetic factor that is associated with development of hepatic encephalopathy in patients with cirrhosis. Primary Funding Source: Instituto de Salud Carlos III, Spanish Ministry of Health. [ABSTRACT FROM AUTHOR]

Preoperative localization of parathyroid pathology, generally a parathyroid adenoma, can be difficult in some cases due to the anatomical variants that these glands present. The objective of this review is to analyse the different imaging techniques used for preoperative localization of parathyroid pathology (scintigraphy, ultrasound, CT, MRI and PET). There is great variability between the different tests for the preoperative localization of parathyroid pathology. The importance of knowing the different diagnostic options lies in the need to choose the most suitable test at each moment and for each patient for an adequate management of primary hyperparathyroidism (PHP) with surgical criteria., (Copyright © 2023. Published by Elsevier España, S.L.U.)

The main aim was to evaluate changes in urea cycle enzymes in NAFLD patients and in two preclinical animal models mimicking this entity. Seventeen liver specimens from NAFLD patients were included for immunohistochemistry and gene expression analyses. Three-hundred-and-eighty-two biopsy-proven NAFLD patients were genotyped for rs1047891, a functional variant located in carbamoyl phosphate synthetase-1 (CPS1) gene. Two preclinical models were employed to analyse CPS1 by immunohistochemistry, a choline deficient high-fat diet model (CDA-HFD) and a high fat diet LDLr knockout model (LDLr -/-). A significant downregulation in mRNA was observed in CPS1 and ornithine transcarbamylase (OTC1) in simple steatosis and NASH-fibrosis patients versus controls. Further, age, obesity (BMI > 30 kg/m 2 ), diabetes mellitus and ALT were found to be risk factors whereas A-allele from CPS1 was a protective factor from liver fibrosis. CPS1 hepatic expression was diminished in parallel with the increase of fibrosis, and its levels reverted up to normality after changing diet in CDA-HFD mice. In conclusion, liver fibrosis and steatosis were associated with a reduction in both gene and protein expression patterns of mitochondrial urea cycle enzymes. A-allele from a variant on CPS1 may protect from fibrosis development. CPS1 expression is restored in a preclinical model when the main trigger of the liver damage disappears., (© 2022. The Author(s).)

Liver fibrosis can be caused by non-alcoholic steatohepatitis (NASH), among other conditions. We performed a study to analyze the effects of a nontoxic, water-soluble extract of the edible mushroom Agaricus bisporus (AB) as a potential inhibitor of fibrosis progression in vitro using human hepatic stellate cell (LX2) cultures and in vivo in LDLR-/- mice. Treatment of LX2 cells with the AB extract reduced the levels of fibrotic and oxidative-related markers and increased the levels of GATA4 expression. In LDLR-/- mice with high-fat diet (HFD)-induced liver fibrosis and inflammation, the progression of fibrosis, oxidative stress, inflammation, and apoptosis were prevented by AB extract treatment. Moreover, in the mouse model, AB extract could exert an antiatherogenic effect. These data suggest that AB mushroom extract seems to exert protective effects by alleviating inflammation and oxidative stress during the progression of liver fibrosis, possibly due to a decrease in Toll-like receptor 4 ( TLR4 ) expression and a reduction in Nod-like receptor protein 3 (NLRP3) inflammasome activation. In addition, we observed a potential atheroprotective effect in our mouse model.

Background: we have based our study on the fact that the labour market is progressively becoming more accessible for people with disabilities. This investigation aims to identify the factors that contribute to high levels of work-related stress in a group of disabled individuals in order to develop policies to prevent it and promote the health of the workforce., Methods: 131 workers from two Special Employment Centres (SECs) of the Amica Association in Cantabria (Spain) participated in the study. Sociodemographic and job-related variables were collected using a questionnaire. Work-related stress was evaluated using the Maslach Burnout Inventory General Survey (MBI-GS), which analyzes emotional exhaustion, cynicism and personal efficacy., Results: the main explanatory factors for higher levels of emotional exhaustion were more than 5 years of service in the company (OR 3.235-IC 95% 1.392-7.519; p = 0.006) and bad job satisfaction (OR 7.615-IC 95% 2.467-23.503; p = 0.0001); higher levels of cynicism were also explained by bad job satisfaction (OR 8.599-IC 95% 2.481-29.799; p = 0.001)., Conclusions: future research is needed to facilitate the design of company policies and promote the well-being of the disabled population in the workplace, to avoid pathological conditions such as burnout syndrome.

Aging is associated with metabolic changes and low-grade inflammation in several organs, which may be due to NLRP3 inflammasome activation. Methods: Here, we asked whether age-related liver changes such as lipid metabolism and fibrosis are reduced in aged mice lacking the NLRP3 inflammasome. We report reduced protein levels of lipid markers (MTP, FASN, DGAT1), SOD activity, oxidative stress marker PTPRG, and the fibrotic markers TPM2β, COL1-α1 associated with increased GATA4, in NLRP3 deficient mice. Fibrotic, lipid, and oxidative reduction in liver tissues of mice was more pronounced in those old KO NLRP3 mice than in the younger ones, despite their greater liver damage. These results suggest that absence of the NLRP3 inflammasome attenuates age-related liver fibrotic pathology in mice, suggesting that pharmacological targeting may be beneficial.

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer and the fourth most frequent cause of cancer-related death worldwide. Sorafenib is the first line recommended therapy for patients with locally advanced/metastatic HCC. The low response rate is attributed to intrinsic resistance of HCC cells to Sorafenib. The potential resistance to Sorafenib-induced cell death is multifactorial and involves all hallmarks of cancer. However, the presence of sub-therapeutic dose can negatively influence the antitumoral properties of the drug. In this sense, the present study showed that the sub-optimal Sorafenib concentration (10 nM) was associated with activation of caspase-9, AMP-activated protein kinase (AMPK), sustained autophagy, peroxisome proliferator-activated receptor-coactivator 1α (PGC-1α) and mitochondrial function in HepG2 cells. The increased mitochondrial respiration by Sorafenib (10 nM) was also observed in permeabilized HepG2 cells, but not in isolated rat mitochondria, which suggests the involvement of an upstream component in this regulatory mechanism. The basal glycolysis was dose dependently increased at early time point studied (6 h). Interestingly, Sorafenib increased nitric oxide (NO) generation that played an inhibitory role in mitochondrial respiration in sub-therapeutic dose of Sorafenib. The administration of sustained therapeutic dose of Sorafenib (10 µM, 24 h) induced mitochondrial dysfunction and dropped basal glycolysis derived acidification, as well as increased oxidative stress and apoptosis in HepG2. In conclusion, the accurate control of the administered dose of Sorafenib is relevant for the potential prosurvival or proapoptotic properties induced by the drug in liver cancer cells., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Hepatitis C virus (HCV) is the main agent responsible for chronic liver disease. Recent advances in anti-HCV treatment strategies have significantly increased the viral clearance rate (>90%). However, sustained antiviral responses vary in different cohorts, and high costs limit the broad use of direct-acting antivirals (DAAs). The goal of this study is to evaluate the inhibitory ability of well characterized (LC-QTOF-MS/MS) aqueous extracts obtained from edible mushrooms (Agaricus bisporus) to diminish HCV viral replication. Our data have demonstrated an in vitro inhibitory effect of A. bisporus extracts on NS3/4A protease and HCV replication. Fractionation by ultra-filtration and sequential liquid-liquid extraction showed that the compounds responsible for the inhibition are water-soluble with low molecular weights (<3 kDa) and that action could be through the following five compounds: ergothioneine, adenine, guanine, hypoxanthine, and xanthine, which are present in all fractions (UF-3, AqF-3 kDa and organic fractions) showing NS3/4A inhibition. Low molecular weight aqueous extracts (<3 kDa) from A. bisporus have potential applications in the prophylaxis and treatment of HCV, especially for patients who do not have access to the last generation of DAAs. They may be useful as well for other flaviviruses, which also possess a NS3 serine protease.

Background: The gut microbiota plays a key role in the maintenance of intestinal homeostasis and the development and activation of the host immune system. It has been shown that commensal bacterial species can regulate the expression of host genes. 16S rRNA gene sequencing has shown that the microbiota in inflammatory bowel disease (IBD) is abnormal and characterized by reduced diversity. MicroRNAs (miRNAs) have been explored as biomarkers and therapeutic targets, since they are able to regulate specific genes associated with Crohn's disease (CD). In this work, we aim to investigate the composition of gut microbiota of active treatment-naïve adult CD patients, with miRNA profile from gut microbiota., Aim: To investigate the composition of gut microbiota of active treatment-naïve adult CD patients, with miRNA profile from gut microbiota., Methods: Patients attending the outpatient clinics at Valme University Hospital without relevant co-morbidities were matched according to age and gender. Faecal samples of new-onset CD patients, free of treatment, and healthy controls were collected. Faecal samples were homogenized, and DNA was amplified by PCR using primers directed to the 16S bacterial rRNA gene. Pyrosequencing was performed using GS-Junior platform. For sequence analysis, MG-RAST server with the database Ribosomal Project was used. MiRNA profile and their relative abundance were analyzed by quantitative PCR., Results: Microbial community was characterized using 16S rRNA gene sequencing in 29 samples ( n = 13 CD patients, and n = 16 healthy controls). The mean Shannon diversity was higher in the healthy control population compared to CD group (5.5 vs 3.7). A reduction in Firmicutes and an increase in Bacteroidetes were found. Clostridia class was also significantly reduced in CD. Principal components analysis showed a grouping pattern, identified in most of the subjects in both groups, showing a marked difference between control and CD groups. A functional metabolic study showed that a lower metabolism of carbohydrates ( P = 0.000) was found in CD group, while the metabolism of lipids was increased. In CD patients, three miRNAs were induced in affected mucosa: mir-144 (6.2 ± 1.3 fold), mir-519 (21.8 ± 3.1) and mir-211 (2.3 ± 0.4)., Conclusion: Changes in microbial function in active non-treated CD subjects and three miRNAs in affected vs non-affected mucosa have been found. miRNAs profile may serve as a biomarker., Competing Interests: Conflict-of-interest statement: All authors declare there are no competing interests in this study.

Genetics and epigenetics play a key role in the development of several diseases, including nonalcoholic fatty liver disease (NAFLD). Family studies demonstrate that first degree relatives of patients with NAFLD are at a much higher risk of the disease than the general population. The development of the Genome Wide Association Study (GWAS) technology has allowed the identification of numerous genetic polymorphisms involved in the evolution of diseases (e.g., PNPLA3 , MBOAT7 ). On the other hand, epigenetic changes interact with inherited risk factors to determine an individual's susceptibility to NAFLD. Modifications of the histones amino-terminal ends are key factors in the maintenance of chromatin structure and gene expression (cAMP-responsive element binding protein H (CREBH) or SIRT1). Activation of SIRT1 showed potential against the physiological mechanisms related to NAFLD. Abnormal DNA methylation represents a starting point for cancer development in NAFLD patients. Besides, the evaluation of circulating miRNA profiles represents a promising approach to assess and non-invasively monitor liver disease severity. To date, there is no approved pharmacologic therapy for NAFLD and the current treatment remains weight loss with lifestyle modification and exercise. In this review, the status of research into relevant genetic and epigenetic modifiers of NAFLD progression will be discussed., Competing Interests: The authors declare no conflict of interest.

Background & aims. G-allele of PNPLA3 (rs738409) favours triglycerides accumulation and steatosis. In this study, we examined the effect of quercetin and natural extracts from mushroom and artichoke on reducing lipid accumulation in hepatic cells., Material and Methods: Huh7.5 cells were exposed to oleic acid (OA) and treated with quercetin and extracts to observe the lipid accumulation, the intracellular-TG concentration and the LD size. Sterol regulatory element binding proteins-1 (SREBP-1), peroxisome proliferator-activated receptor (PPARα-γ) and cholesterol acyltransferase (ACAT) gene expression levels were analysed., Results: Quercetin decreased the intracellular lipids, LD size and the levels of intracellular-TG through the down-regulation of SREBP-1c, PPARγ and ACAT1 increasing PPARα. The natural-extracts suppressed OA-induced lipid accumulation and the intracellular-TG. They down-regulate the hepatic lipogenesis through SREBP-1c, besides the activation of lipolysis through the increasing of PPARα expression., Conclusions: Quercetin and the aqueous extracts decrease intracellular lipid accumulation by down-regulation of lipogenesis and up-regulation of lipolysis.

Background: The effectiveness of the new generation of hepatitis C treatments named direct-acting antiviral agents (DAAs) depends on the genotype, subtype, and resistance-associated substitutions present in individual patients. The aim of this study was to evaluate a massive sequencing platform for the analysis of genotypes and subtypes of hepatitis C virus (HCV) in order to optimize therapy., Methods: A total of 84 patients with hepatitis C were analyzed. The routine genotyping methodology for HCV used at the study institution (Versant HCV Assay, LiPA) was compared with a deep sequencing platform (454/GS-Junior and Illumina MiSeq)., Results: The mean viral load in these HCV patients was 6.89×10 6 ±7.02×10 5 . Viral genotypes analyzed by LiPA were distributed as follows: 26% genotype 1a (22/84), 55% genotype 1b (46/84), 1% genotype 1 (1/84), 2.5% genotype 3 (2/84), 6% genotype 3a (5/84), 6% genotype 4a/c/d (5/84). When analyzed by deep sequencing, the samples were distributed as follows: 27% genotype 1a (23/84), 56% genotype 1b (47/84), 8% genotype 3a (7/84), 5% genotype 4d (4/84), 2.5% genotype 4f (2/84). Six of the 84 patients (7%) were infected with more than one subtype. Among these, 33% (2/6) failed DAA-based triple therapy., Conclusions: The detection of mixed infection could explain some treatment failures. Accurate determination of viral genotypes and subtypes would allow optimal patient management and improve the effectiveness of DAA therapy., (Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Hepatitis C virus (HCV) infection has been related to increased risk of development of hepatocellular carcinoma (HCC) while metformin (M) and statins treatment seemed to protect against HCC development. In this work, we aim to identify the mechanisms by which metformin and simvastatin (S) could protect from liver cancer. Huh7.5 cells were infected with HCV particles and treated with M+S. Human primary hepatocytes were treated with M+S. Treatment with both drugs inhibited Huh7.5 cell growth and HCV infection. In non-infected cells S increased translational controlled tumor protein (TCTP) and phosphatase and tensin homolog (PTEN) proteins while M inhibited mammalian target of rapamycin (mTOR) and TCTP. Simvastatin and metformin co-administered down-regulated mTOR and TCTP, while PTEN was increased. In cells infected by HCV, mTOR, TCTP, p62 and light chain 3B II (LC3BII) were increased and PTEN was decreased. S+M treatment increased PTEN, p62 and LC3BII in Huh7.5 cells. In human primary hepatocytes, metformin treatment inhibited mTOR and PTEN, but up-regulated p62, LC3BII and Caspase 3. In conclusion, simvastatin and metformin inhibited cell growth and HCV infection in vitro. In human hepatocytes, metformin increased cell-death markers. These findings suggest that M+S treatment could be useful in therapeutic prevention of HCV-related hepatocellular carcinoma.

Inflammation and tumorigenesis are tightly linked pathways impacting cancer development. Inflammasomes are key signalling platforms that detect pathogenic microorganisms, including hepatitis C virus (HCV) infection, and sterile stressors (oxidative stress, insulin resistance, lipotoxicity) able to activate pro-inflammatory cytokines interleukin-1β and IL-18. Most of the inflammasome complexes that have been described to date contain a NOD-like receptor sensor molecule. Redox state and autophagy can regulate inflammasome complex and, depending on the conditions, can be either pro- or anti-apoptotic. Acute and chronic liver diseases are cytokine-driven diseases as several proinflammatory cytokines (IL-1α, IL-1β, tumor necrosis factor-alpha, and IL-6) are critically involved in inflammation, steatosis, fibrosis, and cancer development. NLRP3 inflammasome gain of function aggravates liver disease, resulting in severe liver fibrosis and highlighting this pathway in the pathogenesis of non-alcoholic fatty liver disease. On the other hand, HCV infection is the primary catalyst for progressive liver disease and development of liver cancer. It is well established that HCV-induced IL-1β production by hepatic macrophages plays a critical and central process that promotes liver inflammation and disease. In this review, we aim to clarify the role of the inflammasome in the aggravation of liver disease, and how selective blockade of this main pathway may be a useful strategy to delay fibrosis progression in liver diseases., Competing Interests: Conflict-of-interest statement: Authors declare no conflicts of interest.

Sorafenib is the unique accepted molecular targeted drug for the treatment of patients in advanced stage of hepatocellular carcinoma. The current study evaluated cell signaling regulation of endoplasmic reticulum (ER) stress, c-Jun-N-terminal kinase (JNK), Akt, and 5'AMP-activated protein kinase (AMPK) leading to autophagy and apoptosis induced by sorafenib. Sorafenib induced early (3-12 hr) ER stress characterized by an increase of Ser51 P-eIF2α/eIF2α, C/EBP homologous protein (CHOP), IRE1α, and sXBP1, but a decrease of activating transcription factor 6 expression, overall temporally associated with the increase of Thr183,Tyr185 P-JNK1/2/JNK1/2, Thr172 P-AMPKα, Ser413 P-Foxo3a, Thr308 P-AKt/AKt and Thr32 P-Foxo3a/Foxo3a ratios, and reduction of Ser2481 P-mammalian target of rapamycin (mTOR)/mTOR and protein translation. This pattern was related to a transient increase of tBid, Bim EL , Beclin-1, Bcl-xL, Bcl-2, autophagy markers, and reduction of myeloid cell leukemia-1 (Mcl-1) expression. The progressive increase of CHOP expression, and reduction of Thr308 P-AKt/AKt and Ser473 P-AKt/AKt ratios were associated with the reduction of autophagic flux and an additional upregulation of Bim EL expression and caspase-3 activity (24 hr). Small interfering-RNA (si-RNA) assays showed that Bim, but not Bak and Bax, was involved in the induction of caspase-3 in sorafenib-treated HepG2 cells. Sorafenib increased autophagic and apoptotic markers in tumor-derived xenograft model. In conclusion, the early sorafenib-induced ER stress and regulation of JNK and AMPK-dependent signaling were related to the induction of survival autophagic process. The sustained drug treatment induced a progressive increase of ER stress and PERK-CHOP-dependent rise of Bim EL , which was associated with the shift from autophagy to apoptosis. The kinetic of Bim EL expression profile might also be related to the tight balance between AKt- and AMPK-related signaling leading to Foxo3a-dependent BIM EL upregulation., (© 2018 Wiley Periodicals, Inc.)

Background and Aim: A small but significant proportion of patients with normal body mass index show non-alcoholic fatty liver disease (NAFLD). Oxidized low-density lipoprotein (LDL) is a powerful immunogenic molecule, which causes oxidative stress and produces antibodies (oxLDL-ab). We aimed to analyze the role of oxLDL-ab on histological features in lean-NAFLD patients., Methods: Seventy-two biopsy-proven NAFLD patients were included. Lean patients showed body index mass of <30 kg/m(2) . Liver biopsies were assessed by one pathologist blinded to clinical data. Histological features were non-alcoholic steatohepatitis (NASH), steatosis, hepatocellular ballooning, and liver fibrosis. Metabolic and hepatic profiles were analyzed, and lipid-lowering medication was recorded. OxLDL-ab levels were measured by ELISA. OxLDL-ab-based lipid indexes analyzed: oxLDL-ab/total cholesterol ratio; oxLDL-ab/LDL-c ratio; oxLDL-ab/high-density lipoprotein cholesterol (HDL-c) ratio; and oxLDL-ab/oxLDL ratio., Results: Lean-NAFLD patients presented 26.5% (9/34) of NASH. OxLDL-ab/HDL-c ratio (r = 0.570; n = 34; P = 0.001) correlated with NAS score and was the only variable associated with NASH in the multivariate analysis [odds ratio, OR, 1.10 (95% confidence interval, CI: 1.01-1.21); P = 0.039]. Severe steatosis was present in 41.2% (14/34) of lean-NAFLD patients. OxLDL-ab/HDL-c ratio was higher in patients with grade-III steatosis (54.9 (37.3-124.6)) than those with grade II (37.1 (20.2-71.1)) and grade I (17.7 (13.1-22.8)) (P = 0.018). Hepatocellular ballooning was present in 20.6% (7/34) of lean-NAFLD patients, and OxLDL-ab/HDL-c ratio (OR 1.03 [95% CI: 1.01-1.05]; P = 0.050) was independently associated with histological features. OxLDL-ab/HDL-c ratio was higher in patients with advanced fibrosis (39.8 (22.9-121.6) vs 17.7 (13.9-30.9); P = 0.025), increasing gradually with the fibrosis stage (P = 0.042) and remained in the final multivariate model [OR 1.05 (95% CI: 1.00-1.11); P = 0.05]. However, in obese-NAFLD patients, oxLDL/HDL-c ratio was not associated with histological features., Conclusions: Oxidized low-density lipoprotein antibodies/high-density lipoprotein cholesterol ratio could represent an interesting biomarker associated with NASH, hepatocellular ballooning, and liver fibrosis, in lean patients. OxLDL-ab/HDL-c could play an important role for distinguishing patients with and without NAFLD complications., (© 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

Quercetin is a natural flavonoid, which has been shown to have anti hepatitis C virus (HCV) properties. However, the exact mechanisms whereby quercetin impacts the HCV life cycle are not fully understood. We assessed the effect of quercetin on different steps of the HCV life cycle in Huh-7.5 cells and primary human hepatocytes (PHH) infected with HCVcc. In both cell types, quercetin significantly decreased i) the viral genome replication; ii) the production of infectious HCV particles and iii) the specific infectivity of the newly produced viral particles (by 85% and 92%, Huh7.5 and PHH respectively). In addition, when applied directly on HCV particles, quercetin reduced their infectivity by 65%, suggesting that it affects the virion integrity. Interestingly, the HCV-induced up-regulation of diacylglycerol acyltransferase (DGAT) and the typical localization of the HCV core protein to the surface of lipid droplets, known to be mediated by DGAT, were both prevented by quercetin. In conclusion, quercetin appears to have direct and host-mediated antiviral effects against HCV.

It is well established that hepatitis C virus (HCV) infection and replication relies on host lipid metabolism. HCV proteins interact and associate with lipid droplets to facilitate virion assembly and production. Besides, circulating infective particles are associated with very low-density lipoprotein. On the other hand, higher serum lipid levels have been associated with sustained viral response to pegylated interferon and ribavirin therapy in chronic HCV infection, suggesting a relevant role in viral clearance for host proteins. Host and viral genetic factors play an essential role in chronic infection. Lipid metabolism is hijacked by viral infection and could determine the success of viral replication. Recently development of direct acting antiviral agents has shown a very high efficacy (> 90%) in sustained viral response rates even for cirrhotic patients and most of the viral genotypes. HCV RNA clearance induced by Sofosbuvir has been associated with an increased concentration and size of the low-density lipoprotein particles. In this review, host genetic factors, viral factors and the interaction between them will be depicted to clarify the major issues involved in viral infection and lipid metabolism.

Host-viral genetic interaction has a key role in hepatitis C infection (HCV) and maybe in the viral selection. In a preliminary GWAS analysis, we identified BTN3A2 rs9104 to be associated with HCV genotype 1. Therefore, our aim was to determine the influence of BTN family on the selection of HCV genotype. We performed a fine-mapping analysis of BTN gene region in a cohort of chronic HCV infection (N=841), validating significant results in another independent chronic HCV infection cohort (N=637), according to selection of viral genotype. BTN3A2 rs9104, BTN3A2 rs733528, BTN2A1 rs6929846, BTN2A1 rs7763910 and BTN3A3 rs13220495 were associated with viral genotype selection. Interestingly, BTN3A2 rs9104 GG genotype was closely related to genotype 1 infection (80.7% (394/488) compared with genotype 3 infection (53.5% (23/43); P=0.0001) in patients harboring IL28B-CT/TT genotype, although this effect was not observed in IL28B-CC genotype. Similarly, BTN3A3 rs13220495 CC genotype was linked to genotype 3 infection (100% (32/32)) compared to genotype 1 (87.3% (137/157); P=0.028) in patients harboring IL28B-CC genotype, but did not in IL28B-CT/TT genotype. Genetic variants in the butyrophilin family genes may alter susceptibility to infection, selecting HCV genotype and influencing disease progression. BTN3A2 rs9104 was strongly associated with genotype 1 infection and the haplotype BTN3A3 rs13220495 CC+IL28B genotype CC was universal in patients with hepatitis C genotype 3a.

Background: The relationship between 25-hydroxyvitamin D [25(OH)D] serum levels and response to antiviral therapy and laboratory data in HCV infection remains unclear. The aim of this study was to determine pre-treatment 25(OH)D serum level among HCV infected individuals and to evaluate the association between vitamin D status, virological response, and laboratory data., Material and Methods: Baseline serum 25(OH)D levels were measured in 237 chronic HCV infected patients (139 female, age 53.7 ± 11.2 years) using chemiluminescence immunoassay. Correlations between serum 25(OH)D levels, virological and laboratory data regarding HCV infection as well as sustained virological response (SVR) to antiviral therapy were evaluated., Results: Mean serum values of 25(OH)D was 26.2 ± 12 ng/mL and prevalence of vitamin D deficiency (< 30 ng/mL) was 66.2%. Advanced age (> 55 years), high mean values of LDL, total cholesterol, HDL and low mean values of alkaline phosphatase and hemoglobin were statistically associated to vitamin D deficiency. Antiviral treatment was underwent by 133 HCV patients and 44.3% of them achieved SVR. Most of individuals that presented SVR also presented 25(OH)D level higher than 30ng/mL (55.9%). SVR was associated to low mean values of LDL, total cholesterol and platelets; high mean values of ALT, AST and low fibrosis grade., Conclusions: In conclusion, low vitamin D levels were observed among HCV infected patients and was associated to laboratory findings, however baseline 25(OH)D level is not independently associated with SVR.

Background: Anaemia is a common side-effect of ribavirin (RBV) use that overwhelms management of hepatitis C when protease inhibitors are added., Aim: To assess the pharmacogenomic impact of candidate genes SLC28A2, SLC28A3 and ITPA on anaemia in patients receiving triple therapy., Methods: Patients (n=161) with chronic hepatitis C genotype 1 treated with telaprevir (n=95) or boceprevir (n=66) were included. Using RT-PCR we genotyped ITPA (rs1127354, rs7270101) and SLC28A3 (rs56350726, rs10868138) and SLC28A2 (rs11854484). Clinically significant anaemia (CSA) was diagnosed when at least one of the following criteria was observed: (a) haemoglobin <8.5g/dL during treatment; (b) blood transfusion required; (c) erythropoietin administered., Results: CSA occurred in 44% (69/157) of patients and was associated with SLC28A2 rs11854484 [CC/CT genotypes: 33% (26/78) vs. TT genotype: 56% (36/64); p=0.006]. Further, the needed for blood transfusion was related to genotype [CC: 0% (0/18) vs. CT: 13% (8/61) vs. TT: 27% (17/64); p=0.016]. Similarly, ITPA rs1127354 genotypes [AA/AC: 19% (3/16) vs. CC: 45% (61/135; p=0.060] were linked to CSA. In multivariate analysis, SLC28A2 rs11854484 TT genotype (OR:2.33;95%CI:1.10-4.95; p=0.027), female sex (OR:2.54;95% CI:1.13-5.71;p=0.024) and Hb drop at week 4) OR: 1.36; 95CI%: 1.11-1.67; p=0.003) were independently associated with CSA. Similarly, ITPA rs1127354 genotypes [AA/AC: 16% (3/19) vs. CC: 63% (85/134); p=0.0001] and ITPA rs6051702 genotypes [CC/CA: 46% (26/57) vs. CC: 65% (60/93); p=0.023] were related to Hb drop of >3g/dL at week 4., Conclusions: In patients receiving first generation protease inhibitors, genotype SLC28A2 rs11854484 predicts CSA, and helps to identify a subgroup of patients with better tolerance of triple therapy., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Hepatitis C virus (HCV) is classified into seven major genotypes and 67 subtypes. Recent studies have shown that in HCV genotype 1-infected patients, response rates to regimens containing direct-acting antivirals (DAAs) are subtype dependent. Currently available genotyping methods have limited subtyping accuracy. We have evaluated the performance of a deep-sequencing-based HCV subtyping assay, developed for the 454/GS-Junior platform, in comparison with those of two commercial assays (Versant HCV genotype 2.0 and Abbott Real-time HCV Genotype II) and using direct NS5B sequencing as a gold standard (direct sequencing), in 114 clinical specimens previously tested by first-generation hybridization assay (82 genotype 1 and 32 with uninterpretable results). Phylogenetic analysis of deep-sequencing reads matched subtype 1 calling by population Sanger sequencing (69% 1b, 31% 1a) in 81 specimens and identified a mixed-subtype infection (1b/3a/1a) in one sample. Similarly, among the 32 previously indeterminate specimens, identical genotype and subtype results were obtained by direct and deep sequencing in all but four samples with dual infection. In contrast, both Versant HCV Genotype 2.0 and Abbott Real-time HCV Genotype II failed subtype 1 calling in 13 (16%) samples each and were unable to identify the HCV genotype and/or subtype in more than half of the non-genotype 1 samples. We concluded that deep sequencing is more efficient for HCV subtyping than currently available methods and allows qualitative identification of mixed infections and may be more helpful with respect to informing treatment strategies with new DAA-containing regimens across all HCV subtypes., (Copyright © 2015, American Society for Microbiology. All Rights Reserved.)

Ammonia production is implicated in the pathogenesis of hepatic encephalopathy (HE), being intestinal glutaminase activity the main source for ammonia. Management of ammonia formation can be effective in HE treatment by lowering intestinal ammonia production. The use of glutaminase inhibitors represents one way to achieve this goal. In this work, we have performed a search for specific inhibitors that could decrease glutaminase activity by screening two different groups of compounds: i) a group integrated by a diverse, highly pure small molecule compounds derived from thiourea ranging from 200 to 800 Daltons; and ii) a group integrated by commonly use compounds in the treatment of HE. Results shown that THDP-17 (10 µM), a thiourea derivate product, could inhibit the intestinal glutaminase activity (57.4±6.7%). Inhibitory effect was tissue dependent, ranging from 40±5.5% to 80±7.8% in an uncompetitive manner, showing Vmax and Km values of 384.62 µmol min(-1), 13.62 mM with THDP-17 10 µM, respectively. This compound also decreased the glutaminase activity in Caco-2 cell cultures, showing a reduction of ammonia and glutamate production, compared to control cultures. Therefore, the THDP-17 compound could be a good candidate for HE management, by lowering ammonia production.

Background: Hepatitis C virus (HCV) is associated with a higher prevalence of steatosis compared to the general population., Aim: Our aim was to assess the impact of PNPLA3 rs738409 G-allele on steatosis in HCV patients., Material and Methods: We included 474 HCV patients treated with peginterferon plus ribavirin. PNPLA3 rs738409 was genotyped and patients were classified according to alleles and genotypes. Steatosis was detected in 46.4% (220/474). Fibrosis was assessed by Scheuer score. Gene expression was analyzed in Huh7.5 and Huh7 cells using Real Time-PCR., Results: PNPLA3 allele-G was associated with steatosis [54.1% (126/233) vs. 39% (94/241)] (p = 0.0001). In HCV-1, allele-G was related to steatosis [50.6% (82/162) vs. 32.3% (53/164)] (p = 0.001), but did not in HCV-3 [61.9% (26/42) vs. 62% (31/50)] (p = 0.993). PNPLA3 allele-G was associated with steatosis in patients with IL28B-CT/TT [57.7% (82/142) vs. 37.1% (56/151)] (p = 0.0001), but did not in IL28B-CC [47.8% (43/90) vs. 42% (37/88)] (p = 0.442). Independent variables associated with steatosis were: PNPLA3 G-allele [O.R. 1.84 (CI95%: 1.06-3.21); p = 0.007], age [O.R. 1.04 (CI95%: 1.01-1.07); p = 0.017], HCV-genotype 3 [O.R. 2.46 (CI95%: 1.30-4.65); p = 0.006], HOMA > 4 [O.R. 2.72 (CI95%: 1.27-5.82); p = 0.010]. Since PNPLA3 RNA could not be detected on PBMC from HCV patients, an in vitro analysis was performed. Huh7.5 cells infected with JFH1 had a decreased PNPLA3 gene expression (fold inhibition = 3.2 ± 0.2), while Huh7 cells presented increased PNPLA3 gene expression (fold induction = 1.5 ± 0.2)., Conclusion: PNPLA3 allele-G modulated the development of steatosis, particularly in patients with HCV-1 and IL28B-CT/TT genotype, but was not associated with SVR. Metabolic but not viral steatosis seems to be PNPLA3 regulated. Gene interaction may result in differential PNPLA3 gene expression levels in HCV infection.

Hepatitis C virus (HCV) interacts with lipid receptors to enter the cell, circulates as lipoviroparticle and is secreted as VLDL. We aimed to investigate the role of the rs12979860 polymorphism in the IL28B gene in 143 with chronic hepatitis C genotype 1, 144 infected with genotype 3, 90 genotype 4 and 413 noninfected individuals on lipid profile and to test the impact of HCV infection in an in vitro model on VLDL biosynthesis-related gene expression rs12979860 polymorphism was analysed using real-time PCR coupled to Fluorescence Resonance Energy Transfer (FRET). Huh7.5 (rs12979860 CT) and Huh7 (genotype CC) cells were infected with JFH-1 particles and serum from patients infected with genotypes 1 and 3. Gene expression of apolipoprotein B (apoB), microsomal triglyceride transfer protein (MTP), acetyl CoA carboxylase (ACC), diacylglycerol acyltransferase 2 (DGAT2), diacylglycerol acyltransferase 1 (DGAT1) and low-density lipoprotein receptor (LDLr) genes were determined by semiquantitative RT-PCR in vivo and in vitro. Genotype CC rs12979860 polymorphism was associated with significantly higher serum LDL and total cholesterol levels in patients with hepatitis C genotype 1 but not in patients with hepatitis C genotype 3, genotype 4 and control (noninfected) population. Genotype CC was more often seen in genotype 3 and healthy people in comparison with genotype 1; P = 0.001. In vitro results showed that HCV infection promotes lipid metabolism gene expression induction depending on viral genotype, but to a lesser extent in cells with CT genotype. These results demonstrate that IL28B genotype influences lipid metabolism in patients with hepatitis C but not in noninfected and it seems to be viral genotype-mediated. HCV infection modifies lipid-related genes expression (DGAT1 and DGAT2) in cultured cells based on viral genotype and IL28 polymorphism., (© 2013 John Wiley & Sons Ltd.)

Aim: To evaluate the association between 25-hydroxyvitamin D [25(OH)D] and sustained virological response (SVR) in hepatitis C virus (HCV) infected individuals., Methods: Relevant studies were identified by systematically searching MEDLINE databases up to March 2012 and abstracts of the European and American Congress of Hepatology conducted in 2011. Studies must provide information on SVR and the levels of 25(OH)D₃ and/or 25(OH)D₂ [henceforth referred to as 25(OH)D] in sera samples from HCV infected individuals. The inclusion criteria were: clinical studies that included HCV infected patients aged older than 18 years regardless of HCV genotype or ethnic group; provided information on SVR rates; and were reported in the English language as full papers. Due to the heterogeneity of studies in categorizing serum vitamin D levels, a cut-off value of 30 ng/mL of serum 25(OH)D was used. Heterogeneity was assessed using I² statistics. The summary odds ratios with their corresponding 95%CI were calculated based on a random-effects model., Results: Overall, 11 studies (8 observational and 3 interventional) involving 1575 individuals were included and 1117 HCV infected individuals (71%) showed low vitamin D levels. Most of the studies included mono-infected HCV individuals with the mean age ranging from 38 to 56 years. Four studies were conducted in human immunodeficiency virus/HCV infected individuals. Regarding vitamin D measurement, most of the studies employed radioimmunoassays (n = 5) followed by chemiluminescence (n = 4) and just one study employed high performance/pressure liquid chromatography (HPLC). Basal vitamin D levels varied from 17 to 43 ng/mL in the studies selected, and most of the HCV infected individuals had genotype 1 (1068/1575) with mean viral load varying from log 4.5-5.9 UI/mL. With regard to HCV treatment, most of the studies (n = 8) included HCV individuals without previous treatment, where the pooled SVR rate was 46.4%. High rates of SVR were observed in HCV individuals with vitamin D levels above 30 ng/mL (OR = 1.57; 95%CI: 1.12-2.2) and those supplemented with vitamin D (OR = 4.59; 95%CI: 1.67-12.63) regardless of genotype., Conclusion: Our results demonstrated high prevalence of vitamin D deficiency and high SVR in individuals with higher serum vitamin D levels or receiving vitamin D supplementation.

Hepatic encephalopathy is the main cognitive dysfunction in cirrhotic patients associated with impaired prognosis. Hyperammonemia plus inflammatory response do play a crucial role on hepatic encephalopathy. However, in some patients HE appeared without hyperammonemia and patients with increased levels of ammonia could not show cognitive dysfunction. This has led to investigate other factors that could act in a synergistic way. Diabetes mellitus and insulin resistance are characterized by releasing and enhancing these pro-inflammatory cytokines and, additionally, has been related to hepatic encephalopathy. Indeed, patients with diabetes showed raised risk of over hepatic encephalopathy in comparison with non-cirrhotics. Type 2 diabetes mellitus could impair hepatic encephalopathy by different mechanisms that include: a) increasing glutaminase activity; b) impairing gut motility and promoting constipation, intestinal bacterial overgrowth and bacterial translocation. Despite of insufficient clarity about the practicability of anti-diabetic therapy and the most efficacious therapy, we would have to pay a special attention to the management of type 2 diabetes mellitus and insulin resistance in cirrhotic patients.

Background: Insulin resistance has been strongly associated with the attainment of sustained viral response (SVR) in hepatitis C patients., Aim: To determine, in a cohort of Spanish patients with chronic hepatitis C treated with peginterferon plus ribavirin (P+R), whether insulin resistance predicts SVR independently of interleukin-28B rs12979860 polymorphism., Methods: Insulin resistance was measured as [HOMA-IR = Insulin (IU/mL)*glucose (mmol/L)/22.5]. Genotype, viral load and histological fibrosis using Scheuer score were also measured. Binary logistic regression analysis was used for statistical purposes., Results: In a cohort of 240 patients [78% genotype 1, 24% showing advanced fibrosis, 71% high viral load (≥800 000 IU/mL), 31% IL28b genotype CC and 50% with HOMA >2] treated with P+R, 126 (53%) reached SVR. HOMA-IR index (HOMA <2: 63% vs. HOMA >2: 42%; P = 0.001 and IL28b (genotype CC: 68% vs. genotype CT/TT: 45%; P = 0.002) were significantly associated with SVR. In multivariable logistic regression analysis in the overall cohort, variables independently associated were: viral genotype OR: 0.29 (95% CI: 0.11-0.78), P = 0.01; fibrosis OR: 1.62 (95% CI: 1.22-2.16), P = 0.001; HOMA-IR OR: 1.22 (95% CI: 1.02-1.47), P = 0.03; and IL28B genotype OR: 2.43 (95% CI: 1.45-4.07), P = 0.001. The analyses also showed that degree of steatosis, HOMA-IR >2, mild fibrosis and IL28B CC genotype were significantly related to SVR in patients infected with HCV genotypes 1&4, but not in those with genotypes 2&3. No differences were seen in glucose, insulin level or HOMA-IR index segregated according to IL28B genotypes., Conclusion: Our results suggest that insulin resistance, fibrosis stage and IL28B polymorphisms were independent variables associated with sustained viral response., (© 2012 Blackwell Publishing Ltd.)

Several receptors have been identified as implicated on viral entry into the hepatocyte; and, this interaction between the virus and potential receptors could modulate infection, spontaneous viral clearance, persistence of the infection and the widespread of the virus as outbreak. Nevertheless, the playing role of each of them remains controversial. The Niemann-Pick type C1 like 1 gene (NPC1L1) receptor has been recently implicated on hepatitis C virus (HCV) entry into the cell and ezetimibe, an anti-cholesterol drug seems to block that, emerging the idea to control hepatitis C outbreak modulating lipid-related receptors. Hepatitis C infection seems to modulate lipid metabolism according to host genetic background. Indeed, it circulates like a lipoviroparticle. The main aim of this field of vision would be to discuss the role of hepatocyte receptors implicated on virus entry, especially NPC1L1 and the therapeutic options derived from the better knowledge about HCV-lipids- receptors interaction.

Insulin is critical for controlling energy functions including glucose and lipid metabolism. Insulin resistance seems to interact with hepatitis C promoting fibrosis progression and impairing sustained virological response to peginterferon and ribavirin. The main aim was to elucidate the direct effect of hepatitis C virus (HCV) infection on insulin signaling both in vitro analyzing gene expression and protein abundance. Huh7.5 cells and JFH-1 viral particles were used for in vitro studies. Experiments were conducted by triplicate in control cells and infected cells. Genes and proteins involved in insulin signaling pathway were modified by HCV infection. Moreover, metformin treatment increased gene expression of PI3K, IRS1, MAP3K, AKT and PTEN more than >1.5 fold. PTP1B, encoding a tyrosin phosphatase, was found highly induced (>3 fold) in infected cells treated with metformin. However, PTP1B protein expression was reduced in metformin treated cells after JFH1 infection. Other proteins related to insulin pathway like Akt, PTEN and phosphorylated MTOR were also found down-regulated. Viral replication was inhibited in vitro by metformin. A strong effect of HCV infection on insulin pathway-related gene and protein expression was found in vitro. These results could lead to the identification of new therapeutic targets in HCV infection and its co-morbidities.

Aim: To investigate the influence of metformin use on liver dysfunction and hepatic encephalopathy in a retrospective cohort of diabetic cirrhotic patients. To analyze the impact of metformin on glutaminase activity and ammonia production in vitro., Methods: Eighty-two cirrhotic patients with type 2 diabetes were included. Forty-one patients were classified as insulin sensitizers experienced (metformin) and 41 as controls (cirrhotic patients with type 2 diabetes mellitus without metformin treatment). Baseline analysis included: insulin, glucose, glucagon, leptin, adiponectin, TNFr2, AST, ALT. HOMA-IR was calculated. Baseline HE risk was calculated according to minimal hepatic encephalopathy, oral glutamine challenge and mutations in glutaminase gene. We performed an experimental study in vitro including an enzymatic activity assay where glutaminase inhibition was measured according to different metformin concentrations. In Caco2 cells, glutaminase activity inhibition was evaluated by ammonia production at 24, 48 and 72 hours after metformina treatment., Results: Hepatic encephalopathy was diagnosed during follow-up in 23.2% (19/82): 4.9% (2/41) in patients receiving metformin and 41.5% (17/41) in patients without metformin treatment (logRank 9.81; p=0.002). In multivariate analysis, metformin use [H.R.11.4 (95% CI: 1.2-108.8); p=0.034], age at diagnosis [H.R.1.12 (95% CI: 1.04-1.2); p=0.002], female sex [H.R.10.4 (95% CI: 1.5-71.6); p=0.017] and HE risk [H.R.21.3 (95% CI: 2.8-163.4); p=0.003] were found independently associated with hepatic encephalopathy. In the enzymatic assay, glutaminase activity inhibition reached 68% with metformin 100 mM. In Caco2 cells, metformin (20 mM) decreased glutaminase activity up to 24% at 72 hours post-treatment (p<0.05)., Conclusions: Metformin was found independently related to overt hepatic encephalopathy in patients with type 2 diabetes mellitus and high risk of hepatic encephalopathy. Metformin inhibits glutaminase activity in vitro. Therefore, metformin use seems to be protective against hepatic encephalopathy in diabetic cirrhotic patients.

Chronic infection with hepatitis C virus (HCV) can induce insulin resistance (IR) in a genotype-dependent manner and contributes to steatosis, progression of fibrosis and resistance to interferon plus ribavirin therapy. Our understanding of HCV-induced IR has improved considerably over the years, but certain aspects concerning its evaluation still remain elusive to clinical researchers. One of the most important issues is elucidating the ideal method for assessment of IR in the setting of hepatitis C. The hyperinsulinaemic euglycaemic clamp is the gold standard method for determining insulin sensitivity, but is impractical as it is labour intensive and time-consuming. To date, all human studies except for four where IR was evaluated in the HCV setting, an estimation of IR has been used rather than direct measurements of insulin-mediated glucose uptake. The most commonly used estimation in the HCV population is the homeostasis model assessment of insulin resistance (HOMA-IR) which is calculated from a single measurement of fasting insulin and glucose. In this article, we review the use and reporting of HOMA in the literature and provide guidance on its appropriate as well as inappropriate use in the hepatitis setting., (© 2011 Blackwell Publishing Ltd.)

Background: A higher baseline homeostasis model assessment of insulin resistance (HOMA-IR) score has sometimes predicted a poorer sustained virological response (SVR) rate to peginterferon/ribavirin therapy in treatment-naïve chronic hepatitis C patients., Aim: To perform a meta-analysis to evaluate the impact of HOMA-IR on SVR in hepatitis C., Methods: Relevant studies were identified by searching Medline and EMBASE. We identified 17 publications that addressed the influence of insulin resistance on SVR. The random effect model of Der Simonian and Laird method were used for heterogeneous studies using the Meta-Disc software 1.4, Madrid, Spain., Results: Normal insulin sensitivity was associated with a higher rate of SVR [odds ratio (OR) 2.86 (95%CI: 1.97-4.16)] in comparison with insulin resistance. Moreover, in separate analysis by genotype selecting studies that used HOMA-IR > 2 as cut-off defining insulin resistance, SVR was higher in patients with HOMA-IR < 2 in all genotypes: HCV-1 [OR: 2.16 (95%CI: 1.51-3.08)], HCV-2&3 [OR: 3.06 (95%CI: 1.06-8.82)] and HCV-4 [OR: 6.65(95%CI: 2.51-17.61)]. Studies reporting no association between HOMA and SVR included easy-to-cure cohorts, analysed variables strongly related with insulin resistance like body mass index, steatosis, hyper γGT, age and fibrosis and reported differences in handling and interpretation of HOMA-IR., Conclusion: Elevated HOMA-IR was associated with a lower cure rate of patients with hepatitis C treated with Peg-IFN-α/ribavirin irrespective of genotype, and the more difficult-to-treat cohort, the better the HOMA-IR prediction. HOMA-IR is, as a surrogate marker of insulin resistance, susceptible to some biases derived from both handling and interpretation., (© 2011 Blackwell Publishing Ltd.)

Insulin resistance has been found to be an independent factor predicting sustained response to peginterferon plus ribavirin in patients with chronic hepatitis C. Insulin resistance seems to be involved in decreased sensitivity to interferon and could block interferon intracellular signaling. Insulin resistance promotes steatosis and fibrosis progression, induces pro-inflammatory cytokine secretion and increases adipose tissue, decreasing interferon availability. Moreover, suppressor of cytokines 3 and protein tyrosine-phosphatase seems to be able to block interferon and insulin signaling, building a feed-forward loop. Insulin resistance can be treated with exercise, diet or through the use of drugs that improve insulin sensitivity, like biguanides or glitazones. A recent controlled, randomized, double-blind clinical trial (TRIC-1) examined the effect of adding metformin to standard therapy in the treatment of hepatitis C. This study demonstrated that women infected with hepatitis C virus genotype 1 and HOMA >2 treated with metformin showed a greater drop in viral load during the first 12 weeks and a doubled sustained viral response in comparison with females receiving placebo. Pioglitazone has been used in previous nonresponders and naïve patients with disappointing results in two pilot trials. The mechanisms by which the virus promotes insulin resistance seems to be genotype-dependent and could explain, at least in part, the discrepancies between insulin sensitizers. Insulin resistance is a new target in the challenging management of chronic hepatitis C., (Copyright 2010 S. Karger AG, Basel.)

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

Scalp defects can have a number of origins, and their repair is dependent upon their location, size and depth. In the case of the scalp, the repair of even small defects is complicated. Local flaps are the reference for the reconstruction of such defects. Knowledge of scalp anatomy is essential for preparing these flaps, which must be based on one or two vascular pedicles to afford a large rotation angle--thereby facilitating closure of the defect. The parietal zone is the location offering the greatest flap mobilization possibilities. We present a case involving the repair of a major pericranial frontoparietal scalp defect. A local transverse posterior transpositioning scalp flap was raised with the posterior auricular and occipital arteries as vascular pedicle. Following repositioning of the flap, a free partial-thickness skin graft from the thigh was used to cover the donor zone. A review is provided of the different techniques for the reconstruction of large scalp defects.