Hepatic steatosis in chronic hepatitis C: baseline host and viral characteristics and influence on response to therapy with peginterferon alpha-2a plus ribavirin

Altering retinol binding protein 4 levels in hepatitis C: Inflammation and steatosis matter

Both hepatitis C virus (HCV) infection and retinol-binding protein 4 (RBP4) might contribute to insulin resistance (IR), how RBP4 links to IR in HCV infection remain elusive. A joint study of a prospective cohort of 842 chronically HCV-infected (CHC) patients (with 842 controls) and a line of HCV core transgenic mice was conducted. Of 842 patients, 771 had completed anti-HCV therapy and 667 had sustained virological responses (SVRs). Compared with controls, CHC patients had lower RBP4 levels. At baseline, age (95% CI β: -0.87~-0.317), BMI (0.516~2.036), triglycerides (0.03~0.127), neutrophil-to-lymphocyte ratio (NLR) (1.561~7.327), and estimated glomerular filtration rate (eGFR) (-0.342~-0.149) levels were associated with RBP4 levels in CHC patients. At 24-week post-therapy, male sex (0.652~8.129), BMI (0.199~1.254), triglycerides (0.039~0.088), uric acid (0.599~3.067), eGFR (-0.247 ~-0.14) levels, and fibrosis-4 (-3.602~-0.039) scores were associated with RBP4 levels in SVR patients; compared with baseline, except genotype 3 HCV-infected patients, SVR patients had increased RBP4 levels, which were comparable with controls, while no HOMA-IR index alteration was noted after SVR. The HCV core transgenic mice exhibited nonobese hepatic steatosis, had higher hepatic RBP4 expression, higher serum levels of RBP4 and triglycerides, but comparable HOMA-IR levels than non-transgenic littermates. In conclusion, steatosis, sex, age, uric acid, NLR, and FIB-4 levels were associated with HCV-related RBP4 levels; BMI, triglycerides, and eGFR levels were associated with non-HCV-related RBP4 levels. Reversal of low RBP4 levels after SVR was evident in non-genotype 3 HCV-infected patients. Steatosis and inflammation linked with metabolic alteration other than IR, determined RBP4 levels in HCV-infected patients.

Metabolic complications of hepatitis C virus infection

Hepatitis C virus (HCV) infection is a systemic disease that is implicated in multiple extrahepatic organ dysfunction contributing to its protean manifestations. HCV is associated with diverse extrahepatic disorders including atherosclerosis, glucose and lipid metabolic disturbances, alterations in the iron metabolic pathways, and lymphoproliferative diseases over and above the traditional liver manifestations of cirrhosis and hepatocellular carcinoma. The orchestration between HCV major proteins and the liver-muscle-adipose axis, poses a major burden on the global health of human body organs, if not adequately addressed. The close and inseparable associations between chronic HCV infection, metabolic disease, and cardiovascular disorders are specifically important considering the increasing prevalence of obesity and metabolic syndrome, and their economic burden to patients, the healthcare systems, and society. Cellular and molecular mechanisms governing the interplay of these organs and tissues in health and disease are therefore of significant interest. The coexistence of metabolic disorders and chronic hepatitis C infection also enhances the progression to liver fibrosis and hepatocellular carcinoma. The presence of metabolic disorders is believed to influence the chronicity and virulence of HCV leading to liver disease progression. This comprehensive review highlights current knowledge on the metabolic manifestations of hepatitis C and the potential pathways in which these metabolic changes can influence the natural history of the disease.

Direct-acting antiviral agents against hepatitis C virus and lipid metabolism

Hepatitis C virus (HCV) infection induces steatosis and is accompanied by multiple metabolic alterations including hyperuricemia, reversible hypocholesterolemia and insulin resistance. Total cholesterol, low-density lipoprotein-cholesterol and triglyceride levels are increased by peginterferon and ribavirin combination therapy when a sustained virologic response (SVR) is achieved in patients with HCV. Steatosis is significantly more common in patients with HCV genotype 3 but interferon-free regimens are not always effective for treating HCV genotype 3 infections. HCV infection increases fatty acid synthase levels, resulting in the accumulation of fatty acids in hepatocytes. Of note, low-density lipoprotein receptor, scavenger receptor class B type I and Niemann-Pick C1-like 1 proteins are candidate receptors that may be involved in HCV. They are also required for the uptake of cholesterol from the external environment of hepatocytes. Among HCV-infected patients with or without human immunodeficiency virus infection, changes in serum lipid profiles are observed during interferon-free treatment and after the achievement of an SVR. It is evident that HCV affects cholesterol metabolism during interferon-free regimens. Although higher SVR rates were achieved with interferon-free treatment of HCV, special attention must also be paid to unexpected adverse events based on host metabolic changes including hyperlipidemia.

Metabolic alterations and hepatitis C: From bench to bedside

In addition to causing cirrhosis and hepatocellular carcinoma, hepatitis C virus (HCV) is thought to cause hypolipidemia, hepatic steatosis, insulin resistance, metabolic syndrome, and diabetes. The viral life cycle of HCV depends on cholesterol metabolism in host cells. HCV core protein and nonstructural protein 5A perturb crucial lipid and glucose pathways, such as the sterol regulatory element-binding protein pathway and the protein kinase B/mammalian target of rapamycin/S6 kinase 1 pathway. Although several lines of transgenic mice expressing core or full HCV proteins exhibit hepatic steatosis and/or dyslipidemia, whether they completely reflect the metabolic alterations in humans with HCV infection remains unknown. Many cross-sectional studies have demonstrated increased prevalences of metabolic alterations and cardiovascular events in patients with chronic hepatitis C (CHC); however, conflicting results exist, primarily due to unavoidable individual variations. Utilizing anti-HCV therapy, most longitudinal cohort studies of CHC patients have demonstrated the favorable effects of viral clearance in attenuating metabolic alterations and cardiovascular risks. To determine the risks of HCV-associated metabolic alterations and associated complications in patients with CHC, it is necessary to adjust for crucial confounders, such as HCV genotype and host baseline glucose metabolism, for a long follow-up period after anti-HCV treatment. Adipose tissue is an important endocrine organ due to its release of adipocytokines, which regulate lipid and glucose metabolism. However, most data on HCV infection and adipocytokine alteration are inconclusive. A comprehensive overview of HCV-associated metabolic and adipocytokine alterations, from bench to bedside, is presented in this topic highlight.

Central portalization correlates with fibrosis but not with risk factors for nonalcoholic steatohepatitis in steatotic chronic hepatitis C

Concomitant steatosis in chronic hepatitis C is associated with fibrosis and unfavorable treatment outcome. Central zone injury in nonalcoholic steatohepatitis (NASH) manifests as central portalization, with centrizonal microvessels and ductular reaction. We investigated whether central portalization in steatotic HCV biopsies would identify patients with metabolic risk factors for NASH. Liver biopsies with chronic hepatitis C and >10% steatosis (n = 65) were evaluated for the degree of steatosis, zonation of steatosis, fibrosis, and nonalcoholic fatty liver disease (NAFLD) activity score. The presence of centrizonal microvessels, sinusoidal capillarization, ductular reaction, and CK7 positive intermediate-phenotype hepatocytes were evaluated by CD34 and CK7 immunostain. The degree of steatosis and fibrosis showed a positive correlation. Additional positive correlations were noted between centrizonal angiogenesis and NAFLD activity score and central portalization and fibrosis. However, neither central portalization nor zonation of steatosis identified patients with metabolic risk factors for NASH. Therefore, central portalization cannot be used as a surrogate marker to identify patients with metabolic risk factors for NASH in steatotic HCV biopsies. The mechanism of centrizonal injury in steatotic HCV hepatitis is not solely attributable to the metabolic risk factors for NASH.

Role of interleukin-28B polymorphism as a predictor of sustained virological response in patients with chronic hepatitis C treated with triple therapy: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Chronic hepatitis C represents an important health problem. The aim of our meta-analysis was to establish the role of reference single nucleotide (rs) 12979860 allele of interleukin-28B (IL28B) CC versus CT+TT genotype (the most researched allele of IL28B) as a predictor of sustained virological response (SVR) in patients with chronic hepatitis C treated with triple therapy.

METHODS

The PubMed, MEDLINE, Lilacs, Scopus, Ovid, EMBASE, Cochrane and Medscape databases as well as abstract books from important gastroenterology and hepatology meetings were searched for all studies published until 15 July 2012 that analysed the relationship between the polymorphism of IL28B and SVR in patients with chronic hepatitis C, genotype 1, treated with pegylated interferon + ribavirin + direct antiviral agents (telaprevir or boceprevir). The following keywords were used: IL28B polymorphism, chronic hepatitis C, sustained virological response, SVR, triple therapy, telaprevir, boceprevir.

RESULTS

Odds ratios (ORs) with 95 % confidence intervals were pooled from five study populations (1,641 cases) using a random-effects model. The SVR rate was significantly higher in patients with the CC genotype of IL28B than in those with non-CC genotypes (CT and TT): OR = 3.91 (95 % CI 2.11-7.28), p < 0.0001. Higher SVR rates were obtained in chronic hepatitis C patients with the CC genotype of IL28B, regardless of their therapeutic status (naïve patients: OR = 3.99 [95 % CI 1.67-9.51], p < 0.0001; and previously treated ones: OR = 2.15 [95 % CI 1.35-3.43], p = 0.001).

CONCLUSION

IL28B polymorphism seems to influence the SVR rate in patients with chronic hepatitis C treated with triple therapy, but further studies are needed to clarify the mechanism and the influence of other factors on the SVR rates.

HCV in liver transplantation

HCV-related cirrhosis represents the leading indication for liver transplantation in the Western countries. HCV reinfection after liver transplantation occurs in virtually all patients transplanted for HCV-related liver disease Histological evidence of chronic HCV infection develops in 50 to 90 % of patients by 12 months after liver transplantation, and cirrhosis occurs in about 20 % of patients within 5 years after transplant. Several studies have evaluated host, viral, and transplant-related factors that might be associated with the severity of HCV recurrence. Among host factors, immunosuppression is one of the major factors that accounts for accelerated HCV recurrence and it has been an area of extensive research and controversy. Donor age, steatosis, and immunogenetic factors are also relevant in determining the outcome in patients transplanted for HCV-related cirrhosis. A major step to prevent complications of HCV recurrence related to the rapid fibrosis is the posttransplant antiviral treatment. Two strategies have been tried: pre-emptive or other strategies as soon as possible after liver transplantation or elective therapy once there is histological evidence of recurrent hepatitis C. Retransplantation due to graft failure from recurrent hepatitis C is rarely an option in the era of organ shortage as it is associated with poor outcome, but many case needs to be considered early in the evolution of disease. New antivirals may change the outcome dramatically of patients transplanted for HCV cirrhosis.

The impact of host metabolic factors on treatment outcome in chronic hepatitis C

Background. Recent data suggest that chronic hepatitis C has to be considered a metabolic disease further to a viral infection. The aim of this study was to elaborate on the complex interactions between hepatitis C virus, host metabolic factors, and treatment response. Methods. Demographic, virological, and histological data from 356 consecutive patients were analyzed retrospectively. Hepatic steatosis, obesity, and insulin resistance were examined in relation to their impact on treatment outcome. Comparison between genotype 1 and 3 patients was performed to identify differences in the determinants of hepatic steatosis. Results. Histological evidence of hepatic steatosis was found in 113 patients, distributed in 20.3%, 9.0%, and 2.5% for grades I, II, and III, respectively. Hepatic steatosis was associated with past alcohol abuse (P = 0.003) and histological evidence of advanced fibrosis (P < 0.001). Older age (OR 2.51, P = 0.002), genotype (OR 3.28, P < 0.001), cirrhosis (OR 4.23, P = 0.005), and hepatic steatosis (OR 2.48, P = 0.001) were independent predictors for nonresponse. Correlations of hepatic steatosis with alcohol, insulin resistance, and fibrosis stage were found similar for both genotypes 1 and 3. Conclusions. Host metabolic factors may predict treatment outcome, and this impact remains significant even in genotype 3, where steatosis has been believed to be exclusively virus related.

Serum leptin and ghrelin in chronic hepatitis C patients with steatosis

AIM: To determine the associations between leptin and ghrelin concentrations and sustained virological response (SVR) in chronic hepatitis C patients with steatosis.

METHODS: We retrospectively assessed 56 patients infected with hepatitis C virus (HCV) genotype-1 and 40 with HCV genotype-3. Patients with decompensated cirrhosis, and those with other causes of chronic liver disease, were excluded. Serum HCV-RNA concentrations were measured before the initiation of treatment; at weeks 12 (for genotype 1 patients), 24 and 48 during treatment; and 24 wk after the end of treatment. Genotype was determined using INNO-LIPA HCV assays, and serum leptin and ghrelin concentrations were measured using enzyme-linked immunosorbent assay. Biopsy specimens were scored according to the Ishak system and steatosis was graded as mild, moderate, or severe, according to the Brunt classification.

RESULTS: Overall, SVR was positively related to the presence of genotype-3, to biopsy-determined lower histological stage of liver disease, and lower grade of steatosis. Patients ≥ 40 years old tended to be less responsive to therapy. In genotype-1 infected patients, SVR was associated with a lower grade of liver steatosis, milder fibrosis, and an absence of insulin resistance. Genotype-1 infected patients who did not achieve SVR had significantly higher leptin concentrations at baseline, with significant increases as the severity of steatosis worsened, whereas those who achieved SVR had higher ghrelin concentrations. In genotype-3 infected patients, SVR was associated only with fibrosis stage and lower homeostasis model assessment insulin resistance at baseline, but not with the degree of steatosis or leptin concentrations. Genotype-3 infected patients who achieved SVR showed significant decreases in ghrelin concentration at end of treatment. Baseline ghrelin concentrations were elevated in responders of both genotypes who had moderate and severe steatosis.

CONCLUSION: Increased serum leptin before treatment may predict non-SVR, especially in HCV genotype-1 infected patients, whereas increased ghrelin may predict SVR in genotype-1.