Hepatitis C and steatosis

Association between MTTP genotype (-493G/T) polymorphism and hepatic steatosis in hepatitis C: a systematic review and meta-analysis

BACKGROUND

Hepatitis C has been associated with the development of hepatic steatosis, which increases the risk of liver cancer. The microsomal triglyceride transporter protein (MTTP), is a lipid transport protein that mediates lipid metabolism and CD1d antigen presentation. The study aimed to explore the association between MTTP genotype (-493G/T) polymorphism and hepatic steatosis in hepatitis C.

METHODS

The database "Pubmed, Cochrane library, CNKI, Web of science, Embase and CBM" were retrieved to identify the literature. The quality of the selected literature was evaluated using the "the Newcastle-Ottawa Scale" (NOS). Relevant data was extracted and analyzed using the Stata software. Heterogeneity was expressed by "Cochran's Q and I2", with I2 ≥ 50% or P < 0.05 indicating high heterogeneity. A random-effects model and subgroup analysis were conducted to identify the sources of heterogeneity. We also used "Funnel plots", "Egger's tests" and "Begg's tests" to evaluate biases in the literature.

RESULTS

The study found a significant and positive association between liver steatosis and the HCV genotype 3 with a dominant model of the MTTP genotype (-493G/T) (OR = 11.57, 95%CI: 4.467-29.962, P < 0.001). In contrast, no correlation was found between hepatic steatosis and either the recessive, homozygous or heterozygous models (OR = 1.142, P = 0.5; OR = 1.581, P = 0.081; OR = 1.029, P = 0.86). There was no significant publication biases, as measured by the Funnel plot, and the Egger's and Begg's tests. Finally, sensitivity analysis showed the obtained results are stable.

CONCLUSIONS

Dominant mutations in the T allele of the MTTP genotype (-493G/T) increase susceptibility to hepatic steatosis in patients presenting with the HCV genotype 3.

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.

Changes in Serum Lipid Profiles among Canine Patients Suffering from Chronic Hepatitis

Hyperlipidemia is a risk factor for nonalcoholic fatty liver disease (NAFLD) in humans. However, the association between serum lipids and canine chronic hepatitis remains unknown. In this study, serum lipids, hepatic profiles, and hepatic ultrasound scores of healthy dogs and dogs with chronic hepatitis were evaluated. Serum triglyceride and cholesterol concentrations were significantly higher (p < 0.01) in dogs with chronic hepatitis. There were 62.2% of dogs with chronic hepatitis accompanied by hypertriglyceridemia, hypercholesterolemia, or both. Positive correlations were observed between serum ALT and cholesterol (r = 0.8287, p < 0.01), serum ALP and cholesterol (r = 0.8436, p < 0.01), serum GGT and cholesterol (r = 0.5640, p < 0.01), serum bile acid and cholesterol (r = 0.3310, p < 0.01) and serum ALP and triglycerides (r = 0.2582, p < 0.05). No significant differences were found between ultrasound scores of diseased dogs with and without hypertriglyceridemia and diseased dogs with and without hypercholesterolemia. Canine chronic hepatitis is associated with hyperlipidemia. A significant positive association was identified between hyperlipidemia, especially hypercholesterolemia, liver enzymes, and bile acid concentration in dogs suffering from chronic hepatitis. The underlying mechanisms connecting hyperlipidemia and canine chronic hepatitis remain elusive.

Fenofibrate, a peroxisome proliferator-activated receptor-alpha agonist, blocks steatosis and alters the inflammatory response in a mouse model of inflammation-dioxin interaction

2,3,7,8-Tetrachlorodibenzo-p-dioxin (dioxin; TCDD) is an environmental contaminant that elicits a variety of toxic effects, many of which are mediated through activation of the aryl hydrocarbon receptor (AhR). Interaction between AhR and the peroxisome proliferator-activated receptor-alpha (PPAR-α), which regulates fatty acid metabolism, has been suggested. Furthermore, with recognition of the prevalence of inflammatory conditions, there is current interest in the potential for inflammatory stress to modulate the response to environmental agents. The aim of this work was to assess the interaction of TCDD with hepatic inflammation modulated by fenofibrate, a PPAR-α agonist. Female, C57BL/6 mice were treated orally with vehicle or fenofibrate (250 mg/kg) for 13 days, and then were given vehicle or 30 μg/kg TCDD. Four days later, the animals received an i.p. injection of lipopolysaccharide-galactosamine (LPS-GalN) (0.05x10⁷ EU/kg and 500 mg/kg, respectively) to incite inflammation, or saline as vehicle control. After 4 h, the mice were euthanized, and blood and liver samples were collected for analysis. Livers of animals treated with TCDD with or without LPS-GalN had increased lipid deposition, and this effect was blocked by fenofibrate. In TCDD/LPS-GalN-treated mice, fenofibrate caused an increase in plasma activity of alanine aminotransferase, a marker of hepatocellular injury. TCDD reduced LPS-GalN-induced apoptosis, an effect that was prevented by fenofibrate pretreatment. LPS-GalN induced an increase in the concentration of interleukin-6 in plasma and accumulation of neutrophils in liver. TCDD exposure enhanced the former response and inhibited the latter one. These results suggest that fenofibrate counteracts the changes in lipid metabolism induced by TCDD but increases inflammation and liver injury in this model of inflammation-TCDD interaction.

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.

Genotype 3-hepatitis C virus’ last line of defense

Chronic infection with hepatitis C virus (HCV) is one of the leading causes of liver disease globally, affecting approximately 71 million people. The majority of them are infected with genotype (GT) 1 but infections with GT3 are second in frequency. For many years, GT3 was considered to be less pathogenic compared to other GTs in the HCV family due to its favorable response to interferon (IFN)-based regimen. However, the growing evidence of a higher rate of steatosis, more rapid progression of liver fibrosis, and lower efficacy of antiviral treatment compared to infection with other HCV GTs has changed this conviction. This review presents the specifics of the course of GT3 infection and the development of therapeutic options for GT3-infected patients in the era of direct-acting antivirals (DAA). The way from a standard of care therapy with pegylated IFN-alpha (pegIFNα) and ribavirin (RBV) through a triple combination of pegIFNα + RBV and DAA to the highly potent IFN-free pangenotypic DAA regimens is discussed along with some treatment options which appeared to be dead ends. Although the implementation of highly effective pangenotypic regimens is the most recent stage of revolution in the treatment of GT3 infection, there is still room for improvement, especially in patients with liver cirrhosis and those who fail to respond to DAA therapies, particularly those containing inhibitors of HCV nonstructural protein 5A.

Fatty liver is not independently associated with the rates of complete response to oral antiviral therapy in chronic hepatitis B patients

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) and chronic hepatitis B (CHB) are common liver diseases. Concurrent NAFLD may affect antiviral treatment outcomes in CHB patients. The aim of this study is to investigate the impact of NAFLD on complete viral suppression ([CVS], HBV DNA <20-100 IU/mL) and/or biochemical response ([BR], ALT of ≤25 U/L for females; 35 U/L for males) in CHB patients who received oral antiviral therapy.

METHODS

A retrospective study of 555 treated CHB patients (187 NAFLD; 368 non-NAFLD) from 2000 to 2016 at a USA medical centre. NAFLD was diagnosed by imaging and/or histology after ruling out secondary causes of hepatic steatosis.

RESULTS

The majority of patients were male (60.7%), Asian (87.56%) and HBeAg-negative (66.7%). NAFLD patients compared to non-NAFLD were more likely HBeAg negative (74.3% vs 62.8%, P = .02), hypertensive (33.2% vs 22.8%, P = .009) and male (67.4% vs 57.3%, P = .02) with a higher mean BMI (25.4 ± 4.3 vs 23.8 ± 4.0 kg/m² , P < .001). Both cohorts achieved similar rates of CVS (86% vs 88%) and BR (38% vs 41%) during the follow-up of up to 60 months (P > .05), but NAFLD had higher cumulative rates of CVS + BR, compared with non-NAFLD patients (32.5% vs 22.8%, P = .03). In multivariate analyses, NAFLD was not independently associated with CVS and/or BR outcomes. Receipt of entecavir or tenofovir (vs older therapies) and lower baseline HBV DNA or higher ALT were positively associated with achieving CVS or BR.

CONCLUSION

Concomitant NAFLD had no impact on the long-term rates of CVS and/or BR in treated CHB patients.

Novel serum biomarkers modified by the body mass index z-score for the detection of liver fibrosis and steatosis in children with chronic hepatitis C

BACKGROUND

There is a need for validation of noninvasive alternatives to liver biopsy for the evaluation of fibrosis in children with chronic hepatitis C (CHC). The aim of this study was to evaluate the diagnostic performance of serum biomarkers modified by the body mass index z-score (BMI z-score) for the detection of fibrosis and steatosis in children with CHC.

METHODS

Thirty children aged 9.4 ± 3.7 years (14 males, 16 females) with CHC underwent liver biopsy. Fibrosis was scored using a 5-point METAVIR scale (≥2 = significant fibrosis). For all the children, the following noninvasive markers were calculated: The aspartate transaminase (AST)-to-platelets ratio index (APRI), the modified APRI (M-APRI: BMI z-score × APRI), the Fibrosis-4 index (FIB-4), the modified FIB-4 (M-FIB-4: BMI z-score × FIB-4), and a novel marker, B-AST (BMI z-score × AST). The area under the receiver operator characteristic curve (AUROC) was calculated to detect significant fibrosis and steatosis.

RESULTS

In the histopathological evaluation, 22/30 (73%) patients presented with fibrosis, and 8/30 (27%) presented with steatosis. For the detection of significant fibrosis, the AUROCs for M-APRI, M-FIB-4 and B-AST were 0.842, 0.823, and 0.848, respectively. For significant steatosis, the AUROCs were more than 0.9 for all markers that included the BMI z-score. B-AST, with a cut-off of 92.8, showed 71% sensitivity and 95% specificity for detecting significant fibrosis. For predicting severe steatosis, B-AST had 100% sensitivity and 92% specificity. Negative values of all three markers that included BMI z-scores excluded all patients with both significant fibrosis and significant steatosis.

CONCLUSIONS

Including the BMI z-score in serum biomarker formulas enhances their diagnostic ability to detect significant fibrosis and steatosis. B-AST may thus act as an effective alternative to liver biopsy.

Adipokines, insulin resistance, hepatic steatosis, and necroinflammation in patients with chronic viral hepatitis

Background: Hypoadiponectinemia and hyperleptinemia, and reductions in the ratio of adiponectin to leptin (A/L ratio) are associated with the development of hepatic necroinflammation in nonalcoholic fatty liver, but the association of the adipokines with hepatic steatosis in chronic viral hepatitis is unclear.

Objective: To investigate the relationship between serum A/L ratio, insulin resistance, degree of hepatic steatosis, and necroinflammation in patients with chronic viral hepatitis.

Methods: We measured serum adiponectin, leptin, and resistin levels, insulin resistance, and analyzed the association between liver histopathology and the level of the adipokines in 44 patients with chronic viral hepatitis before they started treatment.

Results: We found that insulin resistance, leptin, and resistin levels tended to increase in the group with a greater degree of hepatic steatosis and necroinflammation, but that the increase was not significant. The adiponectin/leptin ratio (A/L ratio) in a group with a low degree of hepatic steatosis was significantly higher than it was in the group with a high degree of hepatic steatosis (3.1 ± 3.1 vs 1.2 ± 0.8; P = 0.008). The A/L ratio in a group with low histological activity index (HAI) scores was significantly higher than in the group with high HAI scores (3.7 ± 3.4 vs 1.1 ± 1.1; P = 0.006). Abdominal obesity was the only variable that showed a significant association with the HAI score (P = 0.03).

Conclusion: The serum A/L ratio in patients with chronic viral hepatitis showed a significant inverse association with their degree of hepatic steatosis and necroinflammation.

Liver steatosis in children with chronic hepatitis B and C: Prevalence, predictors, and impact on disease progression

Only scarce data on liver steatosis in children with chronic hepatitis B and C (CHB and CHC) are available. The objective of this study was to evaluate the prevalence, predictors, and impact of hepatic steatosis on children with CHB and CHC. A total of 78 patients aged 11.5 ± 3.4 years were included: 30 (38%) had CHB, and 48 (62%) had CHC. Steatosis was scored on a 5-point scale, as follows: absent; minimal (≤5% hepatocytes affected), mild (6-33%), moderate (34-66%), and severe (>66%). Stepwise logistic regression was used to determine the factors associated with steatosis and moderate-to-severe steatosis. Steatosis was observed in 4/30 (13%) patients with CHB and 13/48 (27%) patients with CHC (P = 0.17). Moderate-to-severe steatosis was observed in 6/78 (8%) patients: 1/30 (3%) had CHB and 5/48 (10%) had CHC (P = 0.40). The body mass index (BMI) z-score was positively associated with the presence of steatosis in children with CHB (odds ratio [OR] = 3.3, 95% confidence interval [CI]: 1.02-10.64). In CHC, steatosis occurred more frequently in patients with hepatitis C virus genotype 3 compared with other genotypes (P = 0.002). In patients with non-3 genotype hepatitis C virus, steatosis was associated with the stage of fibrosis (OR = 3.35, 95% CI: 1.01-11.07) and inversely associated with the duration of infection (OR = 0.74, 95% CI: 0.55-0.97). Moderate-to-severe steatosis was positively associated with the BMI z-score (OR = 3.62, 95% CI: 1.22-10.75) and stage of fibrosis (OR = 3.89, 95% CI: 1.05-14.47). Steatosis is a common finding in children with chronic viral hepatitis. It is associated with metabolic factors in CHB, whereas in patients with CHC, metabolic and viral factors may have a combined effect, leading to more advanced grades of steatosis in children with higher BMI z-scores. Moderate-to-severe steatosis is a predictor of advanced fibrosis in children with CHC.

Nuclear Receptors as Therapeutic Targets in Liver Disease: Are We There Yet?

Nuclear receptors (NR) are ligand-modulated transcription factors that play diverse roles in cell differentiation, development, proliferation, and metabolism and are associated with numerous liver pathologies such as cancer, steatosis, inflammation, fibrosis, cholestasis, and xenobiotic/drug-induced liver injury. The network of target proteins associated with NRs is extremely complex, comprising coregulators, small noncoding microRNAs, and long noncoding RNAs. The importance of NRs as targets of liver disease is exemplified by the number of NR ligands that are currently used in the clinics or in clinical trials with promising results. Understanding the regulation by NR during pathophysiological conditions, and identifying ligands for orphan NR, points to a potential therapeutic approach for patients with liver diseases. An overview of complex NR metabolic networks and their pharmacological implications in liver disease is presented here.

Adiponectin: A biomarker for chronic hepatitis C?

Adiponectin, a hormone primarily synthesized and secreted by adipose tissue, plays a pivotal role in lipid metabolism. Chronic hepatitis C (CHC) infection is characterized by disordered lipid metabolism, which may potentially evolve into steatosis over a period of time. A growing body of evidence appears to link decreased adiponectin plasma levels with severe CHC-related steatosis, which suggests a potential role of this adipokine as a diagnostic and therapeutic target for clinical application. In this review, we have attempted to summarize the current status of adiponectin research in the context of CHC, concentrating predominantly on its roles in CHC, and its potential relevance as a biomarker for CHC.

Adiponectin serum level in chronic hepatitis C infection and therapeutic profile

Hepatic steatosis is commonly seen in the patients with chronic hepatitis C virus (HCV) infection. HCV is closely associated with lipid metabolism, and viral steatosis is more common in genotype 3 infection owing to a direct cytopathic effect of HCV core protein. In non-genotype 3 infection, hepatic steatosis is considered largely to be the result of the alterations in host metabolism; metabolic steatosis is primarily linked with HCV genotype 1. Adipose tissue secretes different hormones involved in glucose and lipid metabolisms. It has been demonstrated that adipocytokines are involved in the pathogenesis of non-alcoholic fatty liver disease, as the decreased plasma adiponectin levels, a soluble matrix protein expressed by adipoctyes and hepatocyte, are associated with liver steatosis. Various studies have shown that steatosis is strongly correlated negatively with adiponectin in the patients with HCV infection. The role of adiponectin in hepatitis C virus induced steatosis is still not completely understood, but the relationship between adiponectin low levels and liver steatosis is probably due to the ability of adiponectin to protect hepatocytes from triglyceride accumulation by increasing β-oxidation of free fatty acid and thus decreasing de novo free fatty acid production.

Fat and iron quantification in the liver: past, present, and future

Liver fat, iron, and combined overload are common manifestations of diffuse liver disease and may cause lipotoxicity and iron toxicity via oxidative hepatocellular injury, leading to progressive fibrosis, cirrhosis, and eventually, liver failure. Intracellular fat and iron cause characteristic changes in the tissue magnetic properties in predictable dose-dependent manners. Using dedicated magnetic resonance pulse sequences and postprocessing algorithms, fat and iron can be objectively quantified on a continuous scale. In this article, we will describe the basic physical principles of magnetic resonance fat and iron quantification and review the imaging techniques of the "past, present, and future." Standardized radiological metrics of fat and iron are introduced for numerical reporting of overload severity, which can be used toward objective diagnosis, grading, and longitudinal disease monitoring. These noninvasive imaging techniques serve an alternative or complimentary role to invasive liver biopsy. Commercial solutions are increasingly available, and liver fat and iron quantitative imaging is now within reach for routine clinical use and may soon become standard of care.

Hepcidin and the iron enigma in HCV infection

An estimated 30-40% of patients with chronic hepatitis C have elevated serum iron, transferrin saturation, and ferritin levels. Clinical data suggest that iron is a co-morbidity factor for disease progression following HCV infection. Iron is essential for a number of fundamental metabolic processes in cells and organisms. Mammalian iron homeostasis is tightly regulated and this is maintained through the coordinated action of sensory and regulatory networks that modulate the expression of iron-related proteins at the transcriptional and/or posttranscriptional levels. Disturbances of iron homeostasis have been implicated in infectious disease pathogenesis. Viruses, similarly to other pathogens, can escape recognition by the immune system, but they need iron from their host to grow and spread. Hepcidin is a 25-aa peptide, present in human serum and urine and represents the key peptide hormone, which modulates iron homeostasis in the body. It is synthesized predominantly by hepatocytes and its mature form is released in circulation. In this review, we discuss recent advances in the exciting crosstalk of molecular mechanisms and cell signaling pathways by which iron and hepcidin production influences HCV-induced liver disease.

Strong correlation by ultrasonography of hepatomegaly and the presence of co-infection in HIV/HCV cirrhotic patients

Objectives

Progression of hepatic fibrosis is accelerated in patients co-infected with human immunodeficiency virus and hepatitis C virus compared to hepatitis C virus mono-infected patients. This study aimed to compare ultrasound features and selected clinical and biochemical variables between patients with human immunodeficiency virus/hepatitis C virus co-infection (n = 16) versus hepatitis C virus mono-infection (n = 16).

Methods

Each patient underwent abdominal ultrasound, and a specific evaluation was performed in order to detect findings consistent with chronic liver disease. Characterization of spleen size, liver structural pattern, diameter of the portal, spleen, and mesenteric veins was based on classical ultrasound parameters. Propensity score was used for control of selection bias and performed using binary logistic regression to generate a score for each patient. The Fisher and Mann–Whitney tests were used to evaluate categorical variables and continuous variables, respectively.

Results

On univariate analysis right hepatic lobe size was larger in human immunodeficiency virus/hepatitis C virus patients (157.06 ± 17.56 mm) compared to hepatitis C virus mono-infected patients (134.94 ± 16.95 mm) (p = 0.0011). The left hepatic lobe was also significantly larger in human immunodeficiency virus/hepatitis C virus patients (115.88 ± 22.69 mm) versus hepatitis C virus mono-infected patients (95.06 ± 24.18 mm) (p = 0.0177). Also, there was a strong correlation between hepatomegaly and co-infection (p = 0.005).

Conclusion

Human immunodeficiency virus infection was the primary variable influencing liver enlargement in this population. Hepatomegaly on ultrasound was more common among cirrhotic human immunodeficiency virus/hepatitis C virus co-infected patients than among cirrhotic hepatitis C virus mono-infected patients. This aspect is very important in the management of human immunodeficiency virus/hepatitis C virus co-infected patients, because screening for hepatocellular carcinoma is necessary in this population.

Clinical and virological characteristics of chronic hepatitis B patients with hepatic steatosis

OBJECTIVE

This study aimed to explore clinical and virological characteristics of chronic hepatitis B (CHB) patients with hepatic steatosis in order to provide a theoretical basis for the prevention and control of hepatic steatosis.

METHODS

A total of 360 CHB inpatients were recruited from Affiliated Dongnan Hospital of Xiamen University and divided into hepatic steatosis group and non-hepatic steatosis group. The body mass index (BMI), waist-to-hip ratio (WHR), fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (GGT), hepatitis B e antigen (HBeAg), hepatitis B virus DNA (HBV DNA) and hepatic histological changes were detected and compared between the two groups. The association of these factors with hepatic steatosis was evaluated in CHB patients.

RESULTS

BMI, FPG, TG, TC, GGT, AST and HBV DNA showed statistically significant differences between two groups (P<0.01). The patients with hepatic steatosis had markedly higher BMI, FBG, TG and TC than those without steatosis did. No significant differences were found in ALT and HBeAg between two groups (P>0.05). In male patients, there was marked difference in the WHR between two groups (P < 0.01), which was not found in female patients (P > 0.05). The severity of hepatic steatosis increased in patients with hepatic steatosis, compared to those without steatosis (P < 0.01), but the severities of inflammation and fibrosis in the non-hepatic steatosis group were dramatically higher than those in the hepatic steatosis group (P < 0.01).

CONCLUSIONS

BMI, WHR, FBG, TG and TC appeared to be influencing factors of CHB combined with hepatic steatosis. Hepatic steatosis in CHB patients was closely related to changes in anthropometric indices and metabolic factors but not HBV. It is necessary to improve these factors to effectively prevent hepatic steatosis in CHB patients.

[Chronic hepatitis C and insulin resistance]

Insulin resistance is frequently associated with chronic liver disease, and the interaction between hepatitis C virus (HCV) infection and insulin resistance is a major public health issue, bound to increase in the near term. Because of their potential synergism on liver disease severity, a better understanding of the clinical consequences of the relationship between HCV infection and insulin resistance is needed. This translates into accelerated liver disease progression, reduced response to anti-viral agents and, in susceptible individuals, increased risk of developing type 2 diabetes. HCV may also cause hepatic steatosis, especially in patients infected with genotype 3, although the clinical impact of viral steatosis is debated. Little is known regarding the effect of anti-diabetic agents on HCV infection, and a possible association between use of exogenous insulin or a sulfonylurea agents and the development of hepatocellular carcinoma has recently been reported. Thus, modified lifestyle and pharmacological modalities are urgently warranted in chronic hepatitis C with metabolic alterations.

Interferon-associated hepatic steatosis is related to discrepancies in biochemical and virological responses of chronic hepatitis C to IFN-based therapy

BACKGROUND AND AIMS

A discrepancy in virological and biochemical responses may occur throughout interferon-based therapy for hepatitis C virus (HCV). We aimed to explore the risk, associated factors, potential mechanisms, and impact on the treatment outcome of the discrepancy.

SUBJECTS AND METHODS

Consecutive 496, chronic HCV-infected patients receiving interferon/ribavirin or peginterferon/ribavirin for 24 weeks with a 24-week follow-up period were enrolled. Of 433 patients with pretreatment liver biopsy, 46 received serial liver biopsies at the end of treatment and end of follow-up to explore the corresponding change in liver histopathology. A virological/biochemical discrepancy was defined as persistently elevated alanine aminotransferase levels throughout the treatment period, despite the seronegativity for HCV RNA at least at the end of treatment. The sustained virological response (SVR) was defined as seronegativity for HCV RNA 6 months after the end of treatment.

RESULTS

Virological/biochemical discrepancy was observed in 28.7 % (137/478) patients. The SVR rate was comparable between patients with (75.2 %, 103/137) and without discrepancy (81.2 %, 277/341, p = 0.14). For patients with discrepancy and SVR, 78 (75.7 %) had a subsequent normalization of alanine aminotransferase. Hepatic steatosis, advanced fibrosis, obesity, older age, peginterferon preparation, and low viral load were independently predictive of a virological/biochemical discrepancy. Serial liver histology showed that significant transient aggravation of hepatic steatosis during interferon-based therapy was observed among patients with a virological/biochemical discrepancy (difference 0.64 ± 0.93, p = 0.022), but not among those without it (difference 0.09 ± 0.69, p = 0.447).

CONCLUSIONS

A virological/biochemical discrepancy no longer exists after treatment cessation in most patients, and had little impact on the HCV treatment outcome. Treatment-related hepatic steatosis might play an important role in the pathogenesis of the discrepancy.

Association between hepatic steatosis and entecavir treatment failure in Chinese patients with chronic hepatitis B

Background

The coexistence of HBV infection and nonalcoholic fatty liver disease (NAFLD) becomes characteristic of liver disease in China, with unknown bilateral influence. We aimed to investigate the effect of hepatic steatosis, a common hepatocyte change in NAFLD, on antiviral therapy in patients with chronic hepatitis B (CHB).

Methods and Findings

We carried out a prospective nested case control study in CHB patients receiving Entecavir for initial antiviral therapy, by recording demographic, anthropometric and clinical data at baseline, 24^wk, 48^wk and 96^wk. Univariate analysis and multivariate logistic regression were applied to find out independent factors of hepatic steatosis and Entecavir treatment failure. The rates of HBV-DNA clearance, HBeAg seroconversion and ALT normalization were compared between CHB patients with and without steatosis by post hoc analysis. A total of 267 Chinese patients with CHB entered final analysis, with overall percentages of hepatic steatosis and HBeAg positive as 30.5% and 62.4%. Multivariate analysis showed waist circumference, serum TG and uric acid levels were independent factors of hepatic steatosis. The response rates to Entecavir were 54.9%, 63.8%, 74.2% at 24^wk, 48^wk and 96^wk. Hepatic steatosis was revealed as an independent factor of Entecavir treatment failure by multivariate logistic regression at 24^wk, 48^wk and 96^wk. In CHB patients with hepatic steatosis, HBV-DNA clearance and HBeAg seroconversion were both lower throughout the follow-up, but only the former reached statistical significance. Besides, ALT normalization was also significantly lower at 24^wk and 48^wk.

Conclusion

Hepatic steatosis is significantly associated with Entecavir treatment failure and metabolic factors are independent factors of hepatic steatosis in CHB patients, which called for a specified antiviral strategy in CHB patients with NAFLD.

Estimation of hepatic proton-density fat fraction by using MR imaging at 3.0 T

PURPOSE

To compare the accuracy of several magnetic resonance (MR) imaging-based methods for hepatic proton-density fat fraction (FF) estimation at 3.0 T, with spectroscopy as the reference technique.

MATERIALS AND METHODS

This prospective study was institutional review board approved and HIPAA compliant. Informed consent was obtained. One hundred sixty-three subjects (39 with known hepatic steatosis, 110 with steatosis risk factors, 14 without risk factors) underwent proton MR spectroscopy and non-T1-weighted gradient-echo MR imaging of the liver. At spectroscopy, the reference FF was determined from frequency-selective measurements of fat and water proton densities. At imaging, FF was calculated by using two-, three-, or six-echo methods, with single-frequency and multifrequency fat signal modeling. The three- and six-echo methods corrected for T2*; the two-echo methods did not. For each imaging method, the fat estimation accuracy was assessed by using linear regression between the imaging FF and spectroscopic FF. Binary classification accuracy of imaging was assessed at four reference spectroscopic thresholds (0.04, 0.06, 0.08, and 0.10 FF).

RESULTS

Regression intercept of two-, three-, and six-echo methods were -0.0211, 0.0087, and -0.0062 (P <.001 for all three) without multifrequency modeling and -0.0237 (P <.001), 0.0022, and -0.0007 with multifrequency modeling, respectively. Regression slope of two-, three-, and six-echo methods were 0.8522, 0.8528, and 0.7544 (P <.001 for all three) without multifrequency modeling and 0.9994, 0.9775, and 0.9821 with multifrequency modeling, respectively. Significant deviation of intercept and slope from 0 and 1, respectively, indicated systematic error. Classification accuracy was 82.2%-90.1%, 93.9%-96.3%, and 83.4%-89.6% for two-, three-, and six-echo methods without multifrequency modeling and 88.3%-92.0%, 95.1%-96.3%, and 94.5%-96.3% with multifrequency modeling, respectively, depending on the FF threshold. T2*-corrected (three- and six-echo) multifrequency imaging methods had the overall highest FF estimation and classification accuracy. Among methods without multifrequency modeling, the T2-corrected three-echo method had the highest accuracy.

CONCLUSION

Non-T1-weighted MR imaging with T2 correction and multifrequency modeling helps accurately estimate hepatic proton-density FF at 3.0 T.

Pathology of chronic hepatitis B and chronic hepatitis C

Histologic evaluation of the liver is a major component in the medical management and treatment algorithm of patients with chronic hepatitis B (HBV) and chronic hepatitis C (HCV). Liver biopsy in these patients remains the gold standard, and decisions on treatment are often predicated on the degree of damage and stage of fibrosis. This article outlines the clinical course and serologic diagnosis of HBV and HCV for the clinician and the pathologist, who together have a close working relationship in managing patients with acute and chronic liver disease. The salient histologic features are elucidated in an attempt to provide the clinician with an understanding of the basic histopathology underlying chronic HCV and HBV.

Hepatitis C virus prevalence and clearance among US blood donors, 2006-2007: associations with birth cohort, multiple pregnancies, and body mass index

BACKGROUND

During the period 1992-1993, the prevalence of hepatitis C virus (HCV) antibodies (anti-HCV) among US blood donors was 0.36%, but contemporary data on the prevalence of antibody to HCV and the prevalence of HCV RNA are lacking.

METHODS

We performed a large, cross-sectional study of blood donors at 6 US blood centers during 2006-2007. Anti-HCV was measured with enzyme-linked immunosorbent assay followed by immunoblot, and HCV RNA was measured with nucleic acid testing. Adjusted odds ratios (aORs) were derived using multivariable logistic regression.

RESULTS

Of 959,281 donors, 695 had anti-HCV detected (prevalence, 0.072%). Of those with anti-HCV, 516 (74%) had test results positive for HCV RNA, and 179 (26%) had test results that were negative for HCV RNA. Compared with the prevalence during the period 1992-1993, prevalence during 2006-2007 was lower and peaked in older age groups. Anti-HCV was associated with a body mass index (BMI) >30 (aOR, 0.6; 95% confidence interval [CI], 0.5-0.8), and among women, it was associated with higher gravidity (aOR for 5 vs 0 pregnancies, 3.2; 95% CI, 1.9-5.4). HCV RNA negative status was associated with black race (aOR, 0.4; 95% CI, 0.2-0.7), having more than a high school education (aOR, 1.6; 95% CI, 1.1-2.4), and BMI >30 (aOR, 2.4; 95% CI, 1.4-3.9).

CONCLUSIONS

Decreasing HCV prevalence is most likely attributable to culling of seropositive donors and a birth cohort effect. We found new associations between anti-HCV prevalence and gravidity and obesity. Recently discovered genetic factors may underlie differences in HCV RNA clearance in black donors.

Hepatic steatosis in hepatitis C is a storage disease due to HCV interaction with microsomal triglyceride transfer protein (MTP)

Liver steatosis is a frequent histological feature in patients chronically infected with hepatitis C virus (HCV). The relationship between HCV and hepatic steatosis seems to be the result of both epigenetic and genetic factors. In vivo and in vitro studies have shown that HCV can alter intrahepatic lipid metabolism by affecting lipid synthesis, oxidative stress, lipid peroxidation, insulin resistance and the assembly and secretion of VLDL. Many studies suggest that HCV-related steatosis might be the result of a direct interaction between the virus and MTP. It has been demonstrated that MTP is critical for the secretion of HCV particles and that inhibition of its lipid transfer activity reduces HCV production. However, higher degrees of hepatic steatosis were found in chronic hepatitis C patients carrying the T allele of MTP -493G/T polymorphism that seems to be associated with increased MTP transcription. We propose here that liver steatosis in hepatitis C could be a storage disease induced by the effects of the virus and of its proteins on the intracellular lipid machinery and on MTP. Available data support the hypothesis that HCV may modulate MTP expression and activity through a number of mechanisms such as inhibition of its activity and transcriptional control. Initial up regulation could favour propagation of HCV while down regulation in chronic phase could cause impairment of triglyceride secretion and excessive lipid accumulation, with abnormal lipid droplets facilitating the "storage" of virus particles for persistent infection.

Lack of association between hepatitis C infection and chronic kidney disease

BACKGROUND & AIMS

Chronic kidney disease (CKD) can have a negative impact on the natural history of hepatitis C virus infection (HCV) infection; patients with HCV and CKD often have adverse outcomes. We evaluated a large and geographically diverse group of patients to determine whether HCV status has an independent effect on the risk of developing CKD.

METHODS

We conducted a cohort study of 167,569 patients included in a national health care claims database from January 1, 2003-December 31, 2006, with a mean follow-up of 25.3 months. We used multivariable logistic regression analyses to measure the independent effect of HCV status on the baseline prevalence of and progression to CKD (estimated glomerular filtration rate, <60 mL/min/1.73 m(2)).

RESULTS

The baseline prevalence of CKD was similar in patients with versus those without HCV (5.3% vs 5.1%, P = .3). Similarly, among patients with preserved renal function at baseline (n = 82,629), there was no difference in the overall progression to CKD in patients with versus those without HCV (3.8% vs 3.5%, P = .1). HCV status was not associated with progression to CKD, even after adjusting for patient demographics, comorbidities, and use of relevant medications (odds ratio, 0.92; 95% confidence interval, 0.79-1.08).

CONCLUSIONS

We found no association between HCV and risk of development of CKD. These data are relevant in counseling HCV patients regarding the impact of HCV on renal function.

Serum levels of adipokines in patients with chronic HCV infection: relationship with steatosis and fibrosis

BACKGROUND AND AIMS

Hepatic steatosis and fibrosis are common histological findings in patients with chronic hepatitis C virus (HCV) infection. In this study we sought to determine whether serum levels of three adipokines (leptin, adiponectin and resistin) show any biochemical correlation with hepatic steatosis and fibrosis in patients with chronic HCV infection.

METHODS

We examined a total of 51 patients with chronic HCV infection (22 males and 29 females, mean BMI: 27.4+/-5kg/m(2)) and 24 healthy control subjects (10 males and 14 females, mean BMI: 23.2+/-3kg/m(2)). Liver steatosis and fibrosis were scored on biopsies. Serum levels of leptin, adiponectin and resistin were determined by ELISA.

RESULTS

HCV genotypes were 1b in 41 patients (80.4%), 3a in three patients (5.9%), 2a in two patients (3.9%), 1a in two patients (3.9%), 1c in one patient (2%), and 2b in one patient (2%). Serum levels of leptin, resistin, and the leptin-to-adiponectin ratio were significantly higher in patients with chronic HCV infection than in controls. Steatosis and fibrosis were detected in 33.3% and 70.5% of chronic HCV patients, respectively. No significant association with serum adipokine levels and degree of steatosis was evident. Low serum levels of resistin were associated with the presence of fibrosis independently of potential confounders.

CONCLUSIONS

Patients with chronic HCV infection display elevated levels of adipokines in their sera. Reduced concentrations of resistin may be a biochemical marker of fibrosis in this patient group.

Fenofibrate and PBA prevent fatty acid-induced loss of adiponectin receptor and pAMPK in human hepatoma cells and in hepatitis C virus-induced steatosis

Adiponectin receptors play a key role in steatosis and inflammation; however, very little is known about regulation of adiponectin receptors in liver. Here, we examined the effects of palmitate loading, endoplasmic reticulum (ER) stress, and the hypolipidemic agent fenofibrate on adiponectin receptor R2 (AdipoR2) levels and AMP-activated protein kinase (AMPK) in human hepatoma Huh7 cells and in Huh.8 cells, a model of hepatitis C-induced steatosis. Palmitate treatment reduced AdipoR2 protein and basal AMPK phosphorylation in Huh7 cells. Fenofibrate treatment preserved AdipoR2 and phosphorylated AMPK (pAMPK) levels in palmitate-treated cells accompanied by reduced triglyceride (TG) accumulation and less activation of ER stress markers CCAAT/enhancer binding (C/EBPbeta) and eukaryotic translation initiation factor 2 alpha. ER stress agents thapsigargin and tunicamycin suppressed AdipoR2 and pAMPK levels in Huh7 cells, while fenofibrate and the chemical chaperone 4-phenylbutyrate (PBA) prevented these changes. AdipoR2 levels were lower in Huh.8 cells and fenofibrate treatment increased AdipoR2 while reducing activation of c-Jun N-terminal kinase and C/EBPbeta expression without changing TG levels. Taken together, these results suggest that fatty acids and ER stress reduce AdipoR2 protein and pAMPK levels, while fenofibrate and PBA might be important therapeutic agents to correct lipid- and ER stress-mediated loss of AdipoR2 and pAMPK associated with nonalcoholic steatohepatitis.

Epidemiology of non-alcoholic fatty liver disease in China

Fatty liver (steatosis) is highly prevalent in China and is more often linked to obesity than to alcoholism. Among more affluent regions of China, the community prevalence of non-alcoholic fatty liver disease (NAFLD) is approximately 15%. With the increasing pandemic of obesity, the prevalence of NAFLD has approximately doubled in the past decade. The risk factors resemble those in other ethnic populations, but it is important to note that ethnic-specific definitions of central obesity, obesity and metabolic syndrome are more useful in assessment of Chinese people. The full range of histological manifestations of NAFLD has been demonstrated in Chinese patients, but to date hepatic severity is generally mild. In contrast to chronic hepatitis C, steatosis is less common in patients with chronic hepatitis B; it is associated with metabolic, and not viral factors and does not appear to affect disease severity. Although long-term outcomes of NAFLD in Chinese populations remain unclear, it may be a predictor of metabolic disorders, diabetes and cardiovascular disease. Public health interventions are therefore indicated to halt or reverse the national trend of obesity in China so as to improve liver as well as metabolic health.

Disease-specific mechanisms of fibrosis: hepatitis C virus and nonalcoholic steatohepatitis

Our mechanistic understanding of liver fibrosis has increased dramatically in recent years for all liver diseases and for hepatitis C and nonalcoholic steatohepatitis (NASH) in particular. Hepatitis C causes liver injury and fibrosis through direct cytopathic means, direct and indirect interactions with hepatic stellate cells, and activation of the immune system. Steatosis and insulin resistance, which are intrinsic deficits in NASH, are also of great importance in hepatitis C and may be induced by viral or host metabolic factors. For NASH, the key mediators of damage include oxidative stress, fat compartmentalization, visceral fat, apoptosis, and adipokine derangement. This article explores in depth the disease-specific mechanisms of fibrosis in hepatitis C and NASH, with a focus on recent developments.

Fatty acid synthase is up-regulated during hepatitis C virus infection and regulates hepatitis C virus entry and production

Hepatitis C virus (HCV) is a major human pathogen that causes serious illness, including acute and chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Using a mass spectrometry-based proteomics approach, we have identified 175 proteins from a cell culture supernatant fraction containing the HCV genotype 2a (JFH1) virus, among which fatty acid synthase (FASN), the multifunctional enzyme catalyzing the de novo synthesis of fatty acids, was confirmed to be highly enriched. Subsequent studies showed that FASN expression increased in the human hepatoma cell line, Huh7, or its derivative, upon HCV infection. Blocking FASN activity by C75, a pharmacological FASN inhibitor, led to decreased HCV production. Reduction of FASN by RNA interference suppressed viral replication in both replicon and infection systems. Remarkably, FASN appeared to be selectively required for the expression of claudin-1, a tight junction protein that was recently identified as an entry coreceptor for HCV, but not for the expression of another HCV coreceptor, CD81. The decrease in Claudin-1 expression resulting from FASN inhibition was accompanied by a decrease in transepithelial electric resistance of Huh7 cells, implying a reduction in the relative tightness of the cell monolayer. Consequently, the entry of human immunodeficiency virus-HCV pseudotypes was significantly inhibited in C75-treated Huh7 cells.

CONCLUSION

As far as we know, this is the first line of evidence that demonstrates that HCV infection directly induces FASN expression, and thus suggests a possible mechanism by which HCV infection alters the cellular lipid profile and causes diseases such as steatosis.

Prevalence and risk factors of hepatic steatosis and its impact on liver injury in Chinese patients with chronic hepatitis B infection

BACKGROUND AND AIMS

The clinical significance of hepatic steatosis in chronic hepatitis B infection (CHB) is unclear. The aims of this study were thus to investigate the prevalence and risk factors for hepatic steatosis in patients with CHB and its relationship with liver injury.

METHODS

Consecutive patients with biopsy-proven CHB at Hangzhou Sixth People's Hospital between January 2005 and June 2007 were included. Patients co-infected with other viruses or suffering from liver disease of any other cause were excluded. Liver steatosis, necroinflammation and fibrosis were assessed by both Brunt and Scheuer classifications.

RESULTS

A total of 1915 patients (1497 men) with a mean age of 31 +/- 9.5 years were analyzed. Hepatic steatosis was present in 260 (14%) patients. The steatosis involved < 33% of hepatocytes in 90% of cases, and was more frequent among men than women (15% vs 8%, P < 0.001). Two-thirds (178 of 260) of patients with steatosis were hepatitis B e antigen (HBeAg)-positive, but there was no correlation with either serum HBeAg status or hepatitis B virus DNA titer. Degree of inflammation and fibrosis were more mild among those with steatosis than those without. Multivariate analysis showed that steatosis was independently associated with body mass index, serum triglyceride, apolipoprotein B, uric acid, and fasting blood glucose. However, fibrosis was only independently associated with age and inflammatory grade, and the latter associated with viral load and fibrosis stage.

CONCLUSIONS

Hepatic steatosis is common in CHB, it is associated with metabolic factors not viral ones, and does not appear to affect the severity of liver disease.

Hepatobiliary pathology

PURPOSE OF REVIEW

Studies are reviewed from the past year concerning the histopathology of liver and biliary diseases and their pathogenesis.

RECENT FINDINGS

Several cases of acute hepatitis E showed portal and periportal hepatitis, with polarization of neutrophils to the interface region and lymphocytes more centrally in the portal tracts. Transfection of hepatitis C virus into cultured fetal hepatocytes resulted in sustained growth of 50-90 nm diameter viral particles. The ductular reaction in nonalcoholic steatohepatitis appears to evolve with fibrosis in response to hepatocyte replicative senescence. Hepatocellular release of hepcidin is critical for iron homeostasis in a manner analogous to pancreatic insulin for glucose homeostasis; this 'endocrine' focus was elaborated in an overview of hemochromatosis. Specific microscopic features of liver-cell adenomas combined with genetic analysis for hepatocyte nuclear factor 1alpha and beta-catenin mutations allows differentiation into four variants. Steroid-sensitive biliary strictures resembling primary sclerosing cholangitis but with increased serum immunoglobulin G4 and infiltrating immunoglobulin G4-positive plasma cells ('immunoglobulin associated cholangitis') are part of a spectrum of disorders including autoimmune pancreatitis and inflammatory pseudotumor.

SUMMARY

Pathologic features of viral hepatitis C and E, immunohistochemistry for the ductular reaction and malignant liver tumors and several systemic disorders are among recent important pathology studies.