Iron and HFE or TfR1 mutations as comorbid factors for development and progression of chronic hepatitis C

A Two-Pronged Nanostrategy of Iron Metabolism Disruption to Synergize Tumor Therapy by Triggering the Paraptosis-Apoptosis Hybrid Pathway

Iron metabolism has emerged as a promising target for cancer therapy; however, the innate metabolic compensatory capacity of cancer cells significantly limits the effectiveness of iron metabolism therapy. Herein, bioactive gallium sulfide nanodots (GaSx), with dual functions of "reprogramming" and "interfering" iron metabolic pathways, were successfully developed for tumor iron metabolism therapy. The constructed GaSx nanodots ingeniously harness hydrogen sulfide (H2S) gas, which is released in response to the tumor microenvironment, to reprogram the inherent transferrin receptor 1 (TfR1)-ferroportin 1 (FPN1) iron metabolism axis in cancer cells. Concurrently, the gallium ions (Ga3+) derived from GaSx act as a biochemical "Trojan horse", mimicking the role of iron and displacing it from essential biomolecular binding sites, thereby influencing the fate of cancer cells. By leveraging the dual mechanisms of Ga3+-mediated iron disruption and H2S-facilitated reprogramming of iron metabolic pathways, GaSx prompted the initiation of a paraptosis-apoptosis hybrid pathway in cancer cells, leading to marked suppression of tumor proliferation. Importantly, the dysregulation of iron metabolism induced by GaSx notably increased tumor cell susceptibility to both chemotherapy and immune checkpoint blockade (ICB) therapy. This study underscores the therapeutic promise of gas-based interventions and metal ion interference strategies for the tumor metabolism treatment.

Biochanin A protects against iron overload associated knee osteoarthritis via regulating iron levels and NRF2/System xc-/GPX4 axis

BACKGROUND

Iron homeostasis plays a positive role in articular cartilage health. Excessive iron or iron overload can induce oxidative stress damage in chondrocytes and ferroptosis cell death, advancing knee osteoarthritis (KOA). However, up to date, few effective agents treat iron overload-induced KOA (IOKOA). Chinese herbal medicine (CHM) provides abundant resources for drug selection to manage bone metabolic conditions, including osteoporosis. Biochanin A (BCA) is a novel bioactive multifunctional natural compound isolated from Huangqi, which has protective effects on bone loss. Nevertheless, the function and mechanism of BCA in treating IOKOA are still elusive.

PURPOSE

This study seeks to uncover the potential therapeutic targets and mechanisms of BCA in the management of KOA with iron accumulation.

METHODS

Iron dextrin (500 mg/kg) was intraperitoneally injected into mice to establish the iron overloaded mice model. OA was induced through surgery, and the progression was evaluated eight weeks following surgery. OA severity was evaluated with micro-CT and Safranin-O/Fast green staining in vivo. Iron deposition in the knee joint and synovium was assessed using Perl's Prussian blue staining. Ferric ammonium citrate (FAC) was then administered to primary chondrocytes to evaluate iron regulators mediated iron homeostasis. Toluidine blue staining was utilized to identify chondrocytes in vitro. The vitality of the cells was assessed using the CCK-8 test. The apoptosis rate of cells was measured using Annexin V-FITC/PI assay. The intracellular iron level was detected utilizing the calcein-AM test. Reactive oxygen species (ROS), lipid-ROS, and mitochondrial membrane potentiality were reflected via fluorescence density. Utilizing RT-qPCR and western blotting, the expression level was determined.

RESULTS

Micro-CT and histological staining of knee joints showed greater cartilage degradation and higher iron buildup detected in iron-overloaded mice. BCA can reduce iron deposition and the severity of KOA. Toluidine blue staining and the CCK-8 assay indicated that BCA could rescue chondrocytes killed by iron. Cell apoptosis rates were increased due to iron overload but improved by BCA. Further, the intracellular content of iron, ROS, and lipid-ROS was increased with ferric ammonium citrate (FAC) treatment but restored after treatment with different concentrations of BCA. JC-1 staining revealed that BCA could reduce mitochondrial damage induced by iron overload.

CONCLUSION

Iron overload was shown to promote chondrocyte ferroptosis in vivo and in vitro. Moreover, iron overload suppressed the expression of collagen II and induced MMP expression by catalyzing ROS generation with mitochondrial dysfunction. Our results showed that BCA could directly reduce intracellular iron concentration by inhibiting TfR1 and promoting FPN but also target the Nrf2/system xc-/GPX4 signaling pathway to scavenge free radicals and prevent lipid peroxidation. The results of this research indicate that BCA regulates iron homeostasis during the progression of osteoarthritis, which can open a new field of treatment for KOA.

Clinical Factors Associated with Hepatocellular Iron Deposition in End-stage Liver Disease

Background and Aims: Hepatocellular iron accumulation in patients with chronic liver disease has been linked to adverse outcomes. The objective of this study was to identify clinical factors associated with hemosiderosis. Methods: A total of 103 consecutive liver transplant recipients were identified, in whom liver biopsy had been performed prior to transplantation. Laboratory and clinical data at biopsy and transplant were abstracted from the medical records and hepatocyte iron was graded in the biopsy and explant. The association of change in iron score from biopsy to transplant, with the time interval between these two events, was examined using linear mixed model analysis for repeated measures. Results: Most subjects had advanced fibrosis (F3-F4) at liver biopsy, which was performed on average about 2.5 years before transplant. Over 80% of patients had no or 1+ hepatocyte iron at biopsy; iron increased between biopsy and transplant in about 40%. The only demographic or clinical feature that correlated with increased iron was the presence of a transjugular intrahepatic portosystemic shunt. Increased iron at transplant was associated with higher serum iron and transferrin saturation at biopsy, and with lower hemoglobin level, greater mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration, higher ferritin and model for end-stage liver disease score at transplant. Conclusions: The development of hemosiderosis in end-stage liver disease is associated with lower hemoglobin levels and alterations in red blood cell indices that are suggestive of hemolysis. These observations suggest that extravascular hemolysis may play a role in the development of secondary iron overload.

Prevalence and characteristics of anti-HCV positivity and chronic hepatitis C virus infection in HFE p.C282Y homozygotes

INTRODUCTION AND AIM

Observations of hepatitis C virus (HCV) infection in adults with hemochromatosis are limited.

MATERIALS AND METHODS

We determined associations of serum ferritin (SF) with anti-HCV in non-Hispanic white North American adults in a post-screening examination. Cases included p.C282Y homozygotes (regardless of screening transferrin saturation (TS) and SF) and participants (regardless of HFE genotype) with high screening TS/SF. Controls included participants without p.C282Y or p.H63D who had normal screening TS/SF. Participants with elevated alanine aminotransferase underwent anti-HCV testing. We determined prevalence of chronic HCV infection in consecutive Alabama and Ontario referred adults with HFE p.C282Y homozygosity.

RESULTS

In post-screening participants, anti-HCV prevalence was 0.3% [95% CI: 0.02, 2.2] in 294 p.C282Y homozygotes, 9.5% [7.2, 12.3] in 560 Cases without p.C282Y homozygosity, and 0.7% [0.2, 2.3] in 403 Controls. Anti-HCV was detected in 7.2% of 745 participants with and 0.8% of 512 participants without elevated SF (odds ratio 9.9 [3.6, 27.6]; p<0.0001). Chronic HCV infection prevalence in 961 referred patients was 1.0% (10/961) [95% confidence interval (CI): 0.5, 2.0]. Ten patients with chronic HCV infection had median age 45y (range 29-67) and median SF 1163μg/L (range 303-2001). Five of eight (62.5%) patients had biopsy-proven cirrhosis.

CONCLUSIONS

Odds ratio of anti-HCV was increased in post-screening participants with elevated SF. Prevalence of anti-HCV in post-screening participants with HFE p.C282Y homozygosity and chronic HCV infection in referred adults with HFE p.C282Y homozygosity in North America is similar to that of Control participants with HFE wt/wt and normal screening TS/SF.

Iron-Induced Liver Injury: A Critical Reappraisal

Iron is implicated in the pathogenesis of a number of human liver diseases. Hereditary hemochromatosis is the classical example of a liver disease caused by iron, but iron is commonly believed to contribute to the progression of other forms of chronic liver disease such as hepatitis C infection and nonalcoholic fatty liver disease. In this review, we present data from cell culture experiments, animal models, and clinical studies that address the hepatotoxicity of iron. These data demonstrate that iron overload is only weakly fibrogenic in animal models and rarely causes serious liver damage in humans, calling into question the concept that iron overload is an important cause of hepatotoxicity. In situations where iron is pathogenic, iron-induced liver damage may be potentiated by coexisting inflammation, with the resulting hepatocyte necrosis an important factor driving the fibrogenic response. Based on the foregoing evidence that iron is less hepatotoxic than is generally assumed, claims that assign a causal role to iron in liver injury in either animal models or human liver disease should be carefully evaluated.

Review article: iron disturbances in chronic liver diseases other than haemochromatosis - pathogenic, prognostic, and therapeutic implications

BACKGROUND

Disturbances in iron regulation have been described in diverse chronic liver diseases other than hereditary haemochromatosis, and iron toxicity may worsen liver injury and outcome.

AIMS

To describe manifestations and consequences of iron dysregulation in chronic liver diseases apart from hereditary haemochromatosis and to encourage investigations that clarify pathogenic mechanisms, define risk thresholds for iron toxicity, and direct management METHODS: English abstracts were identified in PubMed by multiple search terms. Full length articles were selected for review, and secondary and tertiary bibliographies were developed.

RESULTS

Hyperferritinemia is present in 4%-65% of patients with non-alcoholic fatty liver disease, autoimmune hepatitis, chronic viral hepatitis, or alcoholic liver disease, and hepatic iron content is increased in 11%-52%. Heterozygosity for the C282Y mutation is present in 17%-48%, but this has not uniformly distinguished patients with adverse outcomes. An inappropriately low serum hepcidin level has characterised most chronic liver diseases with the exception of non-alcoholic fatty liver disease, and the finding has been associated mainly with suppression of transcriptional activity of the hepcidin gene. Iron overload has been associated with oxidative stress, advanced fibrosis and decreased survival, and promising therapies beyond phlebotomy and oral iron chelation have included hepcidin agonists.

CONCLUSIONS

Iron dysregulation is common in chronic liver diseases other than hereditary haemochromatosis, and has been associated with liver toxicity and poor prognosis. Further evaluation of iron overload as a co-morbid factor should identify the key pathogenic disturbances, establish the risk threshold for iron toxicity, and promote molecular interventions.

Comprehensive analysis of HFE gene in hereditary hemochromatosis and in diseases associated with acquired iron overload

BACKGROUND

Patients with hepatitis C virus (HCV) and hepatocellular carcinoma (HCC) may or not develop iron overload (IO), which is associated with worst prognosis, because can cause serious damage to organs. HFE gene controls the iron uptake from gut, particularly in patients with hereditary hemochromatosis (HH).

AIM

To identify associations between HFE coding region in patients exhibiting hereditary hemochromatosis and in diseases associated with acquired IO.

METHODS

We sequenced exons 2 to 5 and boundary introns of HFE gene, evaluating all polymorphic sites in patients presenting hereditary (hemochromatosis) or acquired iron overload HCV and HCC) and in healthy controls, using Sanger sequencing. We also determined the ensemble of extended haplotype in healthy control individuals, including several major histocompatibility complex loci, using sequence specific probes. Haplotype reconstruction was performed using the Arlequin and Phase softwares, and linkage disequilibrium (LD) between histocompatibility loci and HFE gene was performed using the Haploview software.

RESULTS

The HFE*003 allele was overrepresented (f = 71%) and HFE*001 allele was underrepresented (f = 14%) in HH patients compared to all groups. A strong linkage disequilibrium was observed among the H63D-G, IVS2(+4)-C and C282Y-G gene variants, particularly in HH; however, the mutation IVS2(+4)T>C was not directly associated with HH susceptibility. The HFE*001/HFE*002 genotype conferred susceptibility to HCC in HCV patients exhibiting IO (P = 0.02, OR = 14.14). Although HFE is telomeric to other histocompatibility genes, the H63D-G/IVS2(+4)-C (P ≤ 0.00001/P ≤ 0.0057) combination was in LD with HLA-B*44 allele group in healthy controls. No LD was observed between HFE alleles and other major histocompatibility loci.

CONCLUSION

A differential HFE association was observed for HH and for diseases associated with acquired IO (HCV, HCC). Since HFE is very distant from other histocompatibility loci, only weak associations were observed with these alleles.

Elevated serum ferritin level associated with hepatic steatosis and fibrosis in hepatitis C virus-infected patients

BACKGROUND

Serum ferritin is an indicator of iron accumulation in a human body, and it is frequently elevated in patients with systemic inflammatory state in chronic hepatitis C (CHC). Iron accumulation is associated with hepatic fibrosis, steatosis, and unfavorable outcome in CHC patients. We studied the status of elevated serum ferritin level and its association with the liver fibrosis or steatosis in Taiwanese CHC patients.

METHODS

Seven hundred and thirty-eight Taiwanese CHC patients were consecutively included in this study. Laboratory analysis, four indexes of fibrosis (FIB4), histological assessment of fibrosis, and steatosis were assessed by appropriate elevation of serum ferritin level.

RESULTS

Three hundred and one patients (40.8%) had elevated serum ferritin level (sex-specific threshold >1.5 × upper limit of normal). Serum iron level (odds ratio [OR], 1.02; 95% CI, 1.01%-1.03%, p < 0.001), female gender (OR, 1.49; 95% CI, 1.07%-2.08%, p = 0.018), serum gamma-glutamyl transferase level (OR, 1.007; 95% CI, 1.003%-1.01%, p < 0.001), steatosis grade (OR, 1.56; 95% CI, 1.13%-2.16%, p = 0.006), and FIB4 ≥3.25 (OR, 1.63; 95% CI, 1.18%-2.27%, p = 0.003) indexes were associated with high serum ferritin level by multivariate logistic regression analysis. Patients with steatosis (>5%) were associated with older age (OR, 1.01; 95% CI, 1.00%-1.03%, p = 0.015), body mass index (OR, 1.10; 95% CI, 1.05%-1.15%, p < 0.001), and elevated serum ferritin level (OR, 1.001; 95% CI, 1.00%-1.001%, p = 0.024) by multivariate logistic regression analysis. Serum ferritin level also associated with high FIB4 (≥3.25) (OR, 1.001; 95% CI, 1.001%-1.002%, p = 0.010) when multivariate model adjusted together with advanced liver fibrosis by biopsy.

CONCLUSION

Elevated serum ferritin level was noted in 40.8% of Taiwanese CHC patients, and the serum ferritin level was associated with liver steatosis and high FIB4.

Hemochromatosis Gene Polymorphism as a Predictor of Sustained Virological Response to Antiviral Treatment in Egyptian Chronic Hepatitis C Patients

Aim:

The aim of this article is to assess HFE C282Y gene mutations as a predictor of sustained virological response (SVR) to anti-hepatitis C virus (HCV) treatment in Egyptian patients.

Materials and methods:

One hundred and forty chronic hepatitis C (CHC) patients were divided into two groups: 70 patients achieved SVR and 70 patients were nonresponders (NRs). All patients were subjected to quantitative polymerase chain reaction (PCR) at baseline, 12 and 24 weeks after therapy commencement. Deoxyribonucleic acid (DNA) sequencing for HFE (C282Y) was done by restriction fragment length polymorphism PCR.

Results:

Sixty five patients did not have mutation and 5 patients had C282Y mutation (GA) with SVR. While 45 NRs had heterozygous C282Y mutation (GA), 4 patients (5.7%) had homozygous mutation (AA) and 21 patients (30%) had no mutation (GG). The parameters of elevated iron [transferrin saturation (TS; p < 0.001), S iron (p < 0.02), total iron binding capacity (TIBC; p < 0.001), transferrin (p < 0.016), and soluble transferrin receptor (sTfR; p-value, 0.001)] were significantly associated with C282Y mutation. However, there was no significant difference regarding ferritin values and C282Y mutation in NR patients.

Conclusion:

Iron overload was frequently detected in CHC patients and associated with C282Y mutation, while biochemical markers of iron overload and C282Y HFE mutation were negative prognostic factor.

How to cite this article: Mehrez MI, Fattah DSA, Azeem NAA, Saleh MA, Mostafa KM. Hemochromatosis Gene Polymorphism as a Predictor of Sustained Virological Response to Antiviral Treatment in Egyptian Chronic Hepatitis C Patients. Euroasian J Hepato-Gastroenterol 2017;7(2):154-157.

Haplotype Analysis of Hemochromatosis Gene Polymorphisms in Chronic Hepatitis C Virus Infection: A Case Control Study

Background

Chronic hepatitis C virus (HCV) infection is frequently associated with elevated serum iron markers. Polymorphisms in the hemochromatosis (HFE) genes are responsible for iron accumulation in most cases of hemochromatosis, and may play a role in HCV infection.

Objectives

We aimed to assess the prevalence of HFE gene polymorphisms in a group of Iranian HCV-infected patients, and to explore the association of these polymorphisms with HCV infection.

Patients and Methods

HFE gene polymorphisms were examined in a total of 69 HCV patients and 69 healthy controls using polymerase chain reaction and restriction fragment length polymorphism techniques. Haplotype and diplotype analyses were performed using PHASE software.

Results

In a recessive analysis model of the His63Asp (H63D) locus (HH vs. HD + DD), the HH genotype was more common in patients compared to controls (adjusted P = 0.012; OR = 6.42 [95% CI: 1.51 - 27.33]). Also, in a recessive analysis model of the Cys282Tyr (C282Y) locus (CC vs. CY + YY), the CC genotype was more frequent in patients compared to controls (adjusted P = 0.03; OR = 5.06 [95% CI: 1.13 - 22.06]). In addition, there was a significant association between the HC haplotype and the HCDC diplotype and HCV infection.

Conclusions

Polymorphism in the hemochromatosis gene may confer some degree of risk for HCV infection, and individuals carrying the H and C alleles may be susceptible to this disease; however, a larger sample of HCV patients and healthy individuals may be necessary to further illustrate the role of these polymorphisms in HCV.

Incidence of hepatocellular carcinoma reduced by phlebotomy treatment in patients with chronic hepatitis C

OBJECTIVE

To determine the impact of phlebotomy on the laboratory values and the incidence of hepatocellular carcinoma (HCC) in patients with hepatitis C.

METHODS

Study patients with chronic hepatitis C were treated with glycyrrhizin injection and oral ursodeoxycholic acid and either with (n=52) or without (n=50) phlebotomy during the period of 2005-2012. Six phlebotomized patients had previously received interferon therapy and were subsequently excluded from the data analysis. The serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin, alkaline phosphatase, gamma-glutamyl transpeptidase, lactate dehydrogenase, ferritin, iron and albumin, as well as the hemoglobin concentration, platelet count and prothrombin time, were determined. We compared the long-term outcomes based on the incidence of HCC and laboratory values, including the baseline serum ferritin levels, in patients treated with versus without phlebotomy.

RESULTS

In the phlebotomy group, the mean AST and ALT levels decreased significantly at each one-year interval over five years (p<0.01), whereas the platelet counts did not. The incidence of HCC in the phlebotomized patients was significantly lower than that observed in the patients treated without phlebotomy: 10.3% vs. 43.7%, respectively, during the 8-year observation period (p=0.04). The incidence of HCC was also lower in the phlebotomized patients with a normal baseline ferritin level: 0.0% vs. 36.0% in the matched subgroup treated without phlebotomy at year 8. Phlebotomy offered a risk ratio of 0.13, thus suggesting protection against the development of HCC.

CONCLUSION

The incidence of HCC can be reduced by phlebotomy treatment, which should be performed in patients with chronic hepatitis C not receiving or not responding to antiviral therapy.

Iron homeostasis and its regulators over the course of chronic hepatitis C

ABSTRACT: 

Chronic infection with HCV has been diagnosed in approximately 170 million people worldwide. It is an important cause of chronic, progressive liver fibrosis. Late consequences of chronic HCV infection, including liver cirrhosis and hepatocellular carcinoma, have become the major indications for liver transplantation in developed countries. Particular attention is being paid to iron accumulation in chronic hepatitis C and its relation to the current antiviral therapy's efficacy and safety, risk of exacerbation of oxidative stress, development of metabolic disorders and hepatocarcinogenesis. HCV infection disrupts the synthesis of hepcidin, which regulates extracellular iron content. This article discusses the impact of iron on HCV multiplication and the involvement of impaired iron homeostasis in chronic hepatitis C in terms of the pathogenesis of insulin resistance, fatty liver and hepatocarcinogenesis.

Vitamin D status and serum ferritin concentration in chronic hepatitis C virus type 1 infection

The circulating 25-hydroxylated form of vitamin D(3), 25(OH)D, and serum ferritin concentrations have been described to be associated with disease progression in chronic hepatitis C. Both parameters also have been assessed with regard to treatment outcome, however, with divergent results. This study examined both the pre- and posttreatment serum concentrations of 25(OH)D and ferritin in 191 patients infected chronically with hepatitis C virus (HCV) type 1 with regard to liver inflammatory activity (grading), disease progression in terms of fibrosis (staging) and an antiviral treatment outcome. Mean pretreatment serum 25(OH)D and ferritin concentrations were 18 ± 10 ng/ml and 280 ± 225 µg/L, respectively. Multivariate analysis revealed lower pretreatment serum 25(OH)D and higher ferritin concentrations to be significantly related to both severity of inflammatory activity and of fibrotic alterations. Pretreatment serum ferritin concentration, furthermore, unlike 25(OH)D concentration, was found to be associated with a sustained virological response by uni- and multivariate analyses. A sustained virological response was featured by a significant increase in serum 25(OH)D levels (18 ± 10 ng/ml vs. 22 ± 11 ng/ml; P < 0.01), a reduction of serum ferritin concentration (191 ± 156 µg/L vs. 103 ± 63 µg/L; P < 0.001) and a normalization of serum alanine aminotransferase (ALT) and γ-glutamyl-transferase (γ-GT) activities. Taken together, decreased 25(OH)D and increased ferritin serum levels indicate the severity of hepatic inflammation and fibrosis in patients infected chronically with HCV type 1. Elevated ferritin, furthermore, was found to be an independent predictor for standard IFN-based therapy responsiveness.

HCV and oxidative stress in the liver

Hepatitis C virus (HCV) is the etiological agent accounting for chronic liver disease in approximately 2-3% of the population worldwide. HCV infection often leads to liver fibrosis and cirrhosis, various metabolic alterations including steatosis, insulin and interferon resistance or iron overload, and development of hepatocellular carcinoma or non-Hodgkin lymphoma. Multiple molecular mechanisms that trigger the emergence and development of each of these pathogenic processes have been identified so far. One of these involves marked induction of a reactive oxygen species (ROS) in infected cells leading to oxidative stress. To date, markers of oxidative stress were observed both in chronic hepatitis C patients and in various in vitro systems, including replicons or stable cell lines expressing viral proteins. The search for ROS sources in HCV-infected cells revealed several mechanisms of ROS production and thus a number of cellular proteins have become targets for future studies. Furthermore, during last several years it has been shown that HCV modifies antioxidant defense mechanisms. The aim of this review is to summarize the present state of art in the field and to try to predict directions for future studies.

Pathogenic Role of Iron Deposition in Reticuloendothelial Cells during the Development of Chronic Hepatitis C

Aim. Chronic hepatitis C (CHepC) is frequently associated with hepatic iron overload, yet mechanisms underlying iron-induced liver injury have not been elucidated. We examined the significance of iron deposition in hepatocytes (HC) and reticuloendothelial cells (REC) in CHepC. Methods. Stainable hepatic iron was scored according to the iron deposition pattern in 373 patients. The levels of serum soluble TNF- α receptor (sTNFR2) and hepatic hepcidin mRNA and the efficacy of phlebotomy were compared among patients with different iron deposition patterns. Results. Serum transaminase levels and hepatic scores of stage, grade, and steatosis were higher in patients with REC iron staining than in those without. REC iron scores were independently associated with advanced stage. Serum sTNFR2 levels were significantly higher in patients with REC iron than in those without. REC iron scores were independently correlated with sTNFR2 levels. Compared with patients without stainable iron, those with iron overload had decreased ratios of hepcidin mRNA to serum ferritin. The efficacy of phlebotomy was greater in patients with REC iron than in those without REC iron. Conclusions. The present results show the importance of REC iron for the development of CHepC and the therapeutic effect of phlebotomy in CHepC.

Nutrition therapy for liver diseases based on the status of nutritional intake

The dietary intake of patients with nonalcoholic fatty liver disease (NAFLD) is generally characterized by high levels of carbohydrate, fat, and/or cholesterol, and these dietary patterns influence hepatic lipid metabolism in the patients. Therefore, careful investigation of dietary habits could lead to better nutrition therapy in NAFLD patients. The main treatment for chronic hepatitis C (CHC) is interferon-based antiviral therapy, which often causes a decrease in appetite and energy intake; hence, nutritional support is also required during therapy to prevent undernourishment, treatment interruption, and a reduction in quality of life. Moreover, addition of some nutrients that act to suppress viral proliferation is recommended. As a substitutive treatment, low-iron diet therapy, which is relatively safe and effective for preventing hepatocellular carcinoma, is also recommended for CHC patients. Some patients with liver cirrhosis (LC) have decreased dietary energy and protein intake, while the number of LC patients with overeating and obesity is increasing, indicating that the nutritional state of LC patients has a broad spectrum. Therefore, nutrition therapy for LC patients should be planned on an assessment of their complications, nutritional state, and dietary intake. Late evening snacks, branched-chain amino acids, zinc, and probiotics are considered for effective nutritional utilization.

Effect of HFE gene polymorphism on sustained virological response in patients with chronic hepatitis C and elevated serum ferritin

CONTEXT

Abnormal serum ferritin levels are found in approximately 20%-30% of the patients with chronic hepatitis C and are associated with a lower response rate to interferon therapy.

OBJECTIVE

To determine if the presence of HFE gene mutations had any effect on the sustained virological response rate to interferon based therapy in chronic hepatitis C patients with elevated serum ferritin.

METHODS

A total of 44 treatment naÏve patients with histologically demonstrated chronic hepatitis C, all infected with hepatitis C virus genotype non-1 (38 genotype 3; 6 genotype 2) and serum ferritin above 500 ng/mL were treated with interferon (3 MU, 3 times a week) and ribavirin (1.000 mg, daily) for 24 weeks.

RESULTS

Sustained virological response was defined as negative qualitative HCV-RNA more than 24 weeks after the end of treatment. Serum HCV-RNA was measured by qualitative in house polymerase chain reaction with a limit of detection of 200 IU/mL. HFE gene mutation was detected using restriction-enzyme digestion with RsaI (C282Y mutation analysis) and BclI (H63D mutation analysis) in 16 (37%) patients, all heterozygous (11 H63D, 2 C282Y and 3 both). Sustained virological response was achieved in 0 of 16 patients with HFE gene mutations and 11 (41%) of 27 patients without HFE gene mutations (P = 0.002; exact Fisher test).

CONCLUSION

Heterozigozity for H63D and/or C282Y HFE gene mutation predicts absence of sustained virological response to combination treatment with interferon and ribavirin in patients with chronic hepatitis C, non-1 genotype and serum ferritin levels above 500 ng/mL.

Hemochromatosis gene mutations: prevalence and effects on pegylated-interferon and ribavirin therapy response in chronic hepatitis C in sardinia

BACKGROUND/AIMS

Considerable evidence suggests that iron could be a comorbid factor for liver injury in chronic hepatitis C (CHC). Elevated iron indices are frequently described in CHC and may impact negatively on the course of liver disease and on the response to interferon alfa therapy. The aim of this study was to evaluate the frequency of hemochromatosis gene mutations in Sardinian CHC patients, the association with iron overload and the impact on response to therapy.

METHODS

Sixty-nine CHC patients were enrolled. Iron indices, hepatic and viral parameters were detected. C282Y, H63D and S65C mutations were identified through a PCR. Liver biopsy was performed for hepatic fibrosis evaluation. All patients were treated for 6 months (viral genotype 2/3) or 12 months (viral genotype 1/4) with pegylated-interferon 180 mcg once weekly and ribavirin 1000-1200 mg/daily. Sustained virological response (SVR) was defined as undetectable HCV RNA 24 weeks after the end of treatment.

RESULTS

HFE gene mutation was detected in 29 patients (42%). The presence of HFE mutations was significantly associated with elevated transferrin saturation (P < 0.01). Hepatic fibrosis was more advanced in HFE mutation carriers (χ (2), P = 0.04). Among mutation carriers 27.5% achieved responses at the end of treatment compared with 60% of non-carriers (P = 0.005). Patients with HFE wildtype produced significant SVR compared with patients with HFE mutations (P = 0.03).

CONCLUSIONS

The literature shows discordant results about the prevalence, hepatic distribution and possible therapeutic implications of iron overload in chronic hepatitis C. Our findings shows that HFE gene mutations could favor, synergically with CHC and other genetic or acquired factors, the development of liver damage and could influence the outcome of interferon treatment with higher rate of non-response.

Clinical impact of HFE mutations in Japanese patients with chronic hepatitis C

BACKGROUND AND AIM

HFE mutations, a common cause of hereditary hemochromatosis (HH), are reportedly associated with hepatic iron overload, severe liver fibrosis, and good response to interferon treatment in European patients with chronic hepatitis C (CHC). HH shows ethnicity-based differences and little is known about the effects of HH mutations on CHC in the Japanese. Thus, the aim of this study was to clarify the clinical influence of HFE mutations in Japanese CHC patients.

METHODS

In a total of 251 patients with CHC, we analyzed the frequencies of H63D and S65C mutations in the HFE gene, and the influence of these mutations on clinical parameters and response to pegylated-interferon-alpha 2b (PEG-IFN) plus ribavirin therapy.

RESULTS

Fourteen patients (5.6%) carried the H63D mutation; all were heterozygotes. No S65C mutations were found. Only hemoglobin levels in the H63D heterozygotes were higher than in wild-type patients. Eleven of 14 H63D heterozygotes achieved sustained virological response (SVR). On univariate analysis, factors associated with SVR were interleukin 28B (IL28B) polymorphism, age, hepatitis C virus (HCV) genotype, HCV viral load, white blood cell count, stage of fibrosis and H63D mutation. All patients with both TT genotype in IL28B (rs8099917) and H63D mutation in HFE (n = 10) achieved SVR.

CONCLUSIONS

The H63D mutation has little impact on the clinical characteristics of CHC, but is related to favorable response to PEG-IFN plus ribavirin therapy, particularly in patients with the TT allele in IL28B.

Serum ferritin levels are associated with a distinct phenotype of chronic hepatitis C poorly responding to pegylated interferon-alpha and ribavirin therapy

Elevated serum ferritin levels may reflect a systemic inflammatory state as well as increased iron storage, both of which may contribute to an unfavorable outcome of chronic hepatitis C (CHC). We therefore performed a comprehensive analysis of the role of serum ferritin and its genetic determinants in the pathogenesis and treatment of CHC. To this end, serum ferritin levels at baseline of therapy with pegylated interferon-alpha and ribavirin or before biopsy were correlated with clinical and histological features of chronic hepatitis C virus (HCV) infection, including necroinflammatory activity (N = 970), fibrosis (N = 980), steatosis (N = 886), and response to treatment (N = 876). The association between high serum ferritin levels (> median) and the endpoints was assessed by logistic regression. Moreover, a candidate gene as well as a genome-wide association study of serum ferritin were performed. We found that serum ferritin ≥ the sex-specific median was one of the strongest pretreatment predictors of treatment failure (univariate P < 0.0001, odds ratio [OR] = 0.45, 95% confidence interval [CI] = 0.34-0.60). This association remained highly significant in a multivariate analysis (P = 0.0002, OR = 0.35, 95% CI = 0.20-0.61), with an OR comparable to that of interleukin (IL)28B genotype. When patients with the unfavorable IL28B genotypes were stratified according to high versus low ferritin levels, SVR rates differed by > 30% in both HCV genotype 1- and genotype 3-infected patients (P < 0.001). Serum ferritin levels were also independently associated with severe liver fibrosis (P < 0.0001, OR = 2.67, 95% CI = 1.68-4.25) and steatosis (P = 0.002, OR = 2.29, 95% CI = 1.35-3.91), but not with necroinflammatory activity (P = 0.3). Genetic variations had only a limited impact on serum ferritin levels.

CONCLUSION

In patients with CHC, elevated serum ferritin levels are independently associated with advanced liver fibrosis, hepatic steatosis, and poor response to interferon-alpha-based therapy.

Effects of a single dose of oral iron on hepcidin concentrations in human urine and serum analyzed by a robust LC-MS/MS method

BACKGROUND

The measurement of serum hepcidin, a peptide hormone that regulates iron metabolism, is clinically important to the understanding of iron homeostasis in health and disease. To date, the quantification of serum hepcidin levels by conventional immunological detection methods has proven problematic due to challenges in obtaining high quality antibodies which demonstrate good reproducibility. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) has been employed recently for more sensitive quantification of hepcidin; however, this method has high background levels and therefore less than optimal specificity.

METHODS

In order to increase the specificity of the mass spectrometry based assay, we developed a robust, ultra-performance liquid-chromatography-tandem mass spectrometry (UPLC-MS/MS) protocol using multiple selected reaction monitoring (mSRM) for quantification of hepcidin levels in urine and serum of human subjects. With this assay, we assessed levels of hepcidin before and for up to 8 h after oral ingestion of ferrous sulfate in ten adult human subjects without known disease.

RESULTS

The linear response of hepcidin quantitation on each instrument was measured, and the correlation coefficients of these calibrations were r(2)=0.9512±0.0202 (n=5) for urine and r(2)=0.9709±0.0291 (n=5) for serum [r(2)=mean±SD]. Compared to baseline, the levels of urinary hepcidin between 2-4 h and 4-8 h of both women and men showed significant increases with p<0.05 and p<0.001, respectively. The levels of serum hepcidin between 4 h and 8 h in both women and men showed significant increases, compared with baseline values, with both p<0.01. Interestingly, we also observed some degree of oscillation of levels, occurring at later time points.

CONCLUSIONS

We have developed and validated a new method for measuring hepcidin concentrations in human serum and urine and used it to demonstrate early increases with iron supplement in both urinary and serum levels of hepcidin, which return to baseline levels, except in urine samples from men.

The role of trace elements on hepatitis virus infections: a review

The significance of the nutritional roles of trace metals (includes some heavy metals) is widely recognized, since these elements are as constituent components of many metal proteins and metalloenzymes serum trace metals levels, and their ratios are frequently reported to be good marker for diagnosing various diseases. Trace metals play an important role in liver disease particularly liver degeneration. Influence of trace elements has been studied in a large number of viruses belonging to different groups. This review reported the role of some trace elements iron (Fe), copper (Cu), cobalt (Co), manganese (Mn) and zinc (Zn) as well as toxic elements Pb on hepatitis virus infections.

Iron levels in hepatocytes and portal tract cells predict progression and outcomes of patients with advanced chronic hepatitis C

BACKGROUND & AIMS

Iron may influence severity and progression of non-hemochromatotic liver diseases. Our aim was to assess the relationship of iron and HFE genetic variations to progression and outcomes in the HALT-C Trial and whether PegIFN therapy influenced iron variables.

METHODS

Participants were randomized to receive long-term PegIFN [n = 400] or no therapy [n = 413] for 3.5 y, with follow-up for up to 8.7 y [median 6.0 y]. Associations of patient characteristics with iron variables at baseline and over time were carried out using Kaplan-Meier analyses, Cox regression models, and repeated measures analysis of covariance.

RESULTS

Participants who developed clinical outcomes [CTP > 7, ascites, encephalopathy, variceal bleeding, SBP, HCC, death] had significantly higher baseline scores for stainable iron in hepatocytes and in portal tract cells than those without. There were significant direct correlations between stainable iron in portal triads and lobular and total Ishak inflammatory and fibrosis scores [P < 0.0001]. Iron in triads at baseline increased risk of outcomes (HR = 1.35, P = 0.02). Stainable iron in hepatocytes decreased, whereas that in portal stromal cells increased significantly [P < 0.0001] over time. Serum iron and TIBC fell significantly over time [P < 0.0001], as did serum ferritin [P = 0.0003]. Chronic PegIFN treatment did not affect stainable iron. HFE genetic variations did not correlate with outcomes, including development of hepatocellular carcinoma.

CONCLUSIONS

Stainable iron in hepatocytes and portal tract cells is a predictor of progression and clinical and histological outcomes in advanced chronic hepatitis C. Chronic low-dose PegIFN therapy did not improve outcomes, nor iron variables.

Hereditary hemochromatosis: laboratory evaluation

The condition of hereditary hemochromatosis (HH) is caused by gene-dependent protein abnormalities involved in iron absorption, storage, or modulation of iron; these abnormalities result in iron overload. The clinical laboratory plays a significant role in case finding, diagnostic validation, and monitoring HH therapy. Elevated serum iron, transferrin saturation, and ferritin suggest HH, but results can also indicate other forms of hepatocyte injury such as alcoholic or viral hepatitis, or other inflammatory disorders involving the liver. In the context of elevated serum iron, transferrin saturation, and ferritin, and after ruling out secondary causes of iron overload, HFE gene evaluation is the preferred test to confirm the diagnosis of HH. However, 5% to 15% of patients with phenotypic HH do not have HFE gene mutations. In these cases, MRI evaluation or liver biopsy with iron quantification is indicated. The clinical role of hepcidin, the iron modulating protein, is undetermined at this time. Because hepcidin also plays a key role in antimicrobial and inflammatory activities, interpretation of hepcidin serum or urine concentration will require thorough understanding of its complex role in iron regulation.

Genes and hepatitis C: susceptibility, fibrosis progression and response to treatment

Hepatitis C virus contact and infection show three different phenotypes: spontaneous viral clearance (SVC), chronic hepatitis C (CHC) and sustained virological response (SVR) following antiviral treatment. Many factors, including genetics, influence the evolution of these three phenotypes. We performed a literature search (PubMed) up to 31 January 2010 without language restriction to identify relevant studies on genes and hepatitis C. Additional studies were sought by reviewing the reference lists of the identified articles. Meta-analysis (using Meta-disk 1.4) was conducted to evaluate the association of single nucleotide polymorphism (SNP) in the IL28B region and SVR. The candidate gene approach showed strong relationships between human leucocyte antigen class II (DQB1(*) 0301 and DRB1(*) 1101) and SVC. A cirrhosis risk score involving 7 SNPs has been validated recently. The set of odds ratios of studies demonstrated an association between SNP (rs12987960/rs8099917) in the IL28B and SVR in CHC treated with peginterferon plus ribavirin (OR: 4.6; 95% CI: 2.9-7.3). The overall distribution of protective allele correlated with ethnic differences in SVR (Asians, Europeans, Hispanic and Afro-Americans) together with SVC, but not with fibrosis stage or viral load. These polymorphisms did not influence SVR in very-easy-to-treat patients such as genotype 2/3, rapid virological responders or patients with acute hepatitis C. While the genetic fingerprint for fibrosis progression remains elusive, IL28b polymorphism predicts SVC and SVR. However, nearly half of patients achieving SVR did not show favourable genotype. Further genetic signals are warranted to complete the puzzle of factors influencing hepatitis C.

Trends in speciation analysis of some heavy metals in serum of patients with chronic hepatitis C and chronic hepatitis B using differential pulse adsorptive stripping voltammetric measurement and atomic absorption spectrophotometry

The relationships between chronic liver diseases and trace heavy metal contents in blood are debatable and have not been understood clearly. The present study is undertaken to determine Co, Fe, and Ni concentrations in sera from viral hepatitis patients. In all eighty patients with chronic hepatitis (B, C) and 29 healthy individuals were chosen for this study. Donors were selected from different environmental areas, including Aswan, Kom Ombo, and Edfu as polluted areas, and Daraw as an unpolluted area. Co, Fe, and Ni concentrations in patient and healthy blood serum were measured by two different analytical techniques: differential pulse adsorptive stripping voltammetry (DPA(d)SV) and atomic absorption spectrophotometer (AAS). The results reveal that Fe is present in higher level in the blood serum of hepatitis patients than in the healthy control, whereas Co and Ni showed the opposite trend. Hepatitis patients from Edfu area exhibited higher Fe level in their serum than those from the other areas, while hepatitis patients and healthy control from Daraw area (free from pollution) exhibited the lowest metal values. Patients with hepatitis C show lower levels of Co, Ni, and Fe in their serum than those with hepatitis B. A comparative study was carried out between the results using DPA(d)SV and AAS techniques, which are in very good agreements.

HFE gene mutations and Wilson's disease in Sardinia

BACKGROUND

Hypocaeruloplasminaemia can lead to tissue iron storage in Wilson's disease and the possibility of iron overload in long-term overtreated patients should be considered. The HFE gene encodes a protein that is intimately involved in intestinal iron absorption.

AIMS

The aim of this study was to determine the prevalence of the HFE gene mutation, its role in iron metabolism of Wilson's disease patients and the interplay of therapy in copper and iron homeostasis.

METHODS

The records of 32 patients with Wilson's disease were reviewed for iron and copper indices, HFE gene mutations and liver biopsy.

RESULTS

Twenty-six patients were negative for HFE gene mutations and did not present significant alterations of iron metabolism. The HFE mutation was significantly associated with increased hepatic iron content (P<0.02) and transferrin saturation index (P<0.03). After treatment period, iron indices were significantly decreased only in HFE gene wild-type.

CONCLUSIONS

The HFE gene mutations may be an addictional factor in iron overload in Wilson's disease. Our results showed that an adjustment of dosage of drugs could prevent further iron overload induced by overtreatment only in patients HFE wild-type.

The role of iron in the pathophysiology and treatment of chronic hepatitis C

Increased hepatic iron content may be observed in patients with chronic hepatitis C infection, and may contribute to disease severity. The presence of hemochromatosis gene mutations is associated with increased hepatic iron accumulation and may lead to accelerated disease progression. Hepatic iron depletion has been postulated to decrease the risk of hepatocellular carcinoma in patients with cirrhosis due to chronic hepatitis C. It is possible that iron depletion stabilizes or improves liver histology and slows disease progression in these individuals. The present article reviews the prevalence and risk factors for hepatic iron overload in chronic hepatitis C, with emphasis on the available data regarding the efficacy of iron depletion in the treatment of this common liver disease.

The role of iron in the pathophysiology and treatment of chronic hepatitis C

Increased hepatic iron content may be observed in patients with chronic hepatitis C infection, and may contribute to disease severity. The presence of hemochromatosis gene mutations is associated with increased hepatic iron accumulation and may lead to accelerated disease progression. Hepatic iron depletion has been postulated to decrease the risk of hepatocellular carcinoma in patients with cirrhosis due to chronic hepatitis C. It is possible that iron depletion stabilizes or improves liver histology and slows disease progression in these individuals. The present article reviews the prevalence and risk factors for hepatic iron overload in chronic hepatitis C, with emphasis on the available data regarding the efficacy of iron depletion in the treatment of this common liver disease.

Reduced serum hepcidin levels in patients with chronic hepatitis C

BACKGROUND/AIMS

Patients with chronic hepatitis C (CHC) often have increased liver iron, a condition associated with reduced sustained response to antiviral therapy, more rapid progression to cirrhosis, and development of hepatocellular carcinoma. The hepatic hormone hepcidin is the major regulator of iron metabolism and inhibits iron absorption and recycling from erythrophagocytosis. Hepcidin decrease is a possible pathophysiological mechanism of iron overload in CHC, but studies in humans have been hampered so far by the lack of reliable quantitative assays for the 25-amino acid bioactive peptide in serum (s-hepcidin).

METHODS

Using a recently validated immunoassay, we measured s-hepcidin levels in 81 untreated CHC patients and 57 controls with rigorous definition of normal iron status. All CHC patients underwent liver biopsy with histological iron score.

RESULTS

s-hepcidin was significantly lower in CHC patients than in controls (geometric means with 95% confidence intervals: 33.7, 21.5-52.9 versus 90.9, 76.1-108.4 ng/mL, respectively; p<0.001). In CHC patients, s-hepcidin significantly correlated with serum ferritin and histological total iron score, but not with s-interleukin-6. After stratification for ferritin quartiles, s-hepcidin increased significantly across quartiles in both controls and CHC patients (chi for trend, p<0.001). However, in CHC patients, s-hepcidin was significantly lower than in controls for each corresponding quartile (analysis of variance, p<0.001).

CONCLUSIONS

These results, together with very recent studies in animal and cellular models, indicate that although hepcidin regulation by iron stores is maintained in CHC, the suppression of this hormone by hepatitis C virus is likely an important factor in liver iron accumulation in this condition.

Iron increases HMOX1 and decreases hepatitis C viral expression in HCV-expressing cells

AIM: To investigate effects of iron on oxidative stress, heme oxygenase-1 (HMOX1) and hepatitis C viral (HCV) expression in human hepatoma cells stably expressing HCV proteins.

METHODS: Effects of iron on oxidative stress, HMOX1, and HCV expression were assessed in CON1 cells. Measurements included mRNA by quantitative reverse transcription-polymerase chain reaction, and protein levels by Western blots.

RESULTS: Iron, in the form of ferric nitrilotriacetate, increased oxidative stress and up-regulated HMOX1 gene expression. Iron did not affect mRNA or protein levels of Bach1, a repressor of HMOX1. Silencing the up-regulation of HMOX1 nuclear factor-erythroid 2-related factor 2 (Nrf2) by Nrf2-siRNA decreased FeNTA-mediated up-regulation of HMOX1 mRNA levels. These iron effects were completely blocked by deferoxamine (DFO). Iron also significantly decreased levels of HCV core mRNA and protein by 80%-90%, nonstructural 5A mRNA by 90% and protein by about 50% in the Con1 full length HCV replicon cells, whereas DFO increased them.

CONCLUSION: Excess iron up-regulates HMOX1 and down-regulates HCV gene expression in hepatoma cells. This probably mitigates liver injury caused by combined iron overload and HCV infection.

Elevated hepatic iron: a confounding factor in chronic hepatitis C

Historically, iron overload in the liver has been associated with the genetic disorders hereditary hemochromatosis and thalassemia and with unusual dietary habits. More recently, elevated hepatic iron levels also have been observed in chronic hepatitis C virus (HCV) infection. Iron overload in the liver causes many changes including induction of oxidative stress, damage to lysosomes and mitochondria, altered oxidant defense systems and stimulation of hepatocyte proliferation. Chronic HCV infection causes numerous pathogenic changes in the liver including induction of endoplasmic reticulum stress, the unfolded protein response, oxidative stress, mitochondrial dysfunction and altered growth control. Understanding the molecular and cellular changes that could occur in a liver which has elevated hepatic iron levels and in which HCV replication and gene expression are ongoing has clinical relevance and represents an area of research in need of further investigation.

Co-factors in liver disease: the role of HFE-related hereditary hemochromatosis and iron

The severity of liver disease and its presentation is thought to be influenced by many host factors. Prominent among these factors is the level of iron in the body. The liver plays an important role in coordinating the regulation of iron homeostasis and is involved in regulating the level of iron absorption in the duodenum and iron recycling by the macrophages. Iron homeostasis is disturbed by several metabolic and genetic disorders, including various forms of hereditary hemochromatosis. This review will focus on liver disease and how it is affected by disordered iron homeostasis, as observed in hereditary hemochromatosis and due to HFE mutations. The types of liver disease covered herein are chronic hepatitis C virus (HCV) infection, alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), end-stage liver disease, hepatocellular carcinoma (HCC) and porphyria cutanea tarda (PCT).

The effect of iron depletion on chronic hepatitis C virus infection

Increasing evidence exists that iron overload, a common finding in chronic hepatitis C virus (HCV) infection, plays an important role in the pathophysiology of this disease. The mechanisms by which iron excess induces liver damage along with the benefit of iron depletion via phlebotomy on biochemical and histological outcomes in patients with chronic HCV infection have been discussed in this review. Finally, we focus on the effect of iron reduction on the rate of response to interferon antiviral therapy.

Iron chelation beyond transfusion iron overload

The effects of systemic iron overload in hereditary (e.g., classic HFE hemochromatosis) or acquired disorders (e.g., transfusion-dependent iron overload) are well known. Several other iron overload diseases, with an observed mild-to-moderate increase in iron in selected organs (e.g., the liver or the brain), or with "misdistribution" of iron within cells (e.g., reticuloendothelial cells) or subcellular organelles (e.g., mitochondria), have been recognized more recently. The deleterious impact of any excess iron may be high as active redox iron may directly contribute to cell damage or affect signaling pathways involved in cell necrosis-apoptosis or organ fibrosis and cancer. This article discusses the potential use of iron chelation therapy to treat iron overload from causes other than transfusion overload.

Hemochromatosis genotypes and risk of 31 disease endpoints: meta-analyses including 66,000 cases and 226,000 controls

Hemochromatosis genotypes have been associated with liver disease, diabetes mellitus, heart disease, arthritis, porphyria cutanea tarda, stroke, neurodegenerative disorders, cancer, and venous disease. We performed meta-analyses including 202 studies with 66,263 cases and 226,515 controls to examine associations between hemochromatosis genotypes C282Y/C282Y, C282Y/H63D, C282Y/wild type, H63D/H63D, and H63D/wild type versus wild type/wild type and 9 overall endpoints and 22 endpoint subgroups. We also explored potential sources of heterogeneity. For liver disease, the odds ratio for C282Y/C282Y versus wild type/wild type was 3.9 (99% confidence interval: 1.9-8.1) overall, 11 (3.7-34) for hepatocellular carcinoma, 4.1 (1.2-14) for hepatitis C, and 10 (2.1-53) for nonalcoholic steatohepatitis. For porphyria cutanea tarda, the odds ratios were 48 (24-95) for C282Y/C282Y, 8.1 (3.9-17) for C282Y/H63D, 3.6 (1.8-7.3) for C282Y/wild type, 3.0 (1.6-5.6) for H63D/H63D, and 1.7 (1.0-3.1) for H63D/wild type versus wild type/wild type. Finally, for amyotrophic lateral sclerosis, the odds ratio was 3.9 (1.2-13) for H63D/H63D versus wild type/wild type. These findings were consistent across individual studies. The hemochromatosis genotypes were not associated with risk for diabetes mellitus, heart disease, arthritis, stroke, cancer, or venous disease in the overall analyses; however, the odds ratio for C282Y/C282Y versus wild type/wild type was 3.4 (1.1-11) for diabetes mellitus among North Europeans.

CONCLUSION

In aggregate, clinically ascertained cases who are homozygous for the C282Y mutation are associated with a 4-11-fold risk of liver disease, whereas all 5 hemochromatosis genotypes are associated with a 2-48-fold risk of porphyria cutanea tarda, and H63D/H63D is associated with a 4-fold risk of amyotrophic lateral sclerosis. These results, mainly from case-control studies, cannot necessarily be extrapolated to the general population.

HFE gene in primary and secondary hepatic iron overload

Distinct from hereditary haemochromatosis, hepatic iron overload is a common finding in several chronic liver diseases. Many studies have investigated the prevalence, distribution and possible contributory role of excess hepatic iron in non-haemochromatotic chronic liver diseases. Indeed, some authors have proposed iron removal in liver diseases other than hereditary haemochromatosis. However, the pathogenesis of secondary iron overload remains unclear. The High Fe (HFE) gene has been implicated, but the reported data are controversial. In this article, we summarise current concepts regarding the cellular role of the HFE protein in iron homeostasis. We review the current status of the literature regarding the prevalence, hepatic distribution and possible therapeutic implications of iron overload in chronic hepatitis C, hepatitis B, alcoholic and non-alcoholic fatty liver diseases and porphyria cutanea tarda. We discuss the evidence regarding the role of HFE gene mutations in these liver diseases. Finally, we summarize the common and specific features of iron overload in liver diseases other than haemochromatosis.

Review article: the genetic basis of haemochromatosis

BACKGROUND

Since the seminal discovery of the HFE gene a decade ago, considerable further progress in unravelling the genetic basis of haemochromatosis has been made. Novel genes and iron overload phenotypes have been described with potential insights into the molecular pathophysiology of human iron metabolism.

AIM

To review recent key advances in the field of inherited iron overload and assess their impact on clinical practice and on our understanding of iron regulation.

METHODS

A PubMed search was undertaken predominantly using 'haemochromatosis', 'HFE', 'hepcidin' and 'ferroportin'. Illustrative cases were sought.

RESULTS

The impact of HFE mutation analysis on the management of haemochromatosis is significant and allows early accurate diagnosis. HFE is also implicated in the siderosis associated with other liver pathologies. Non-HFE genes underpinning other forms of haemochromatosis are now recognized and genotype-phenotype interactions result in a spectrum of disease. These novel gene products interact with HFE in a common pathway for iron homeostasis.

CONCLUSIONS

Further identification of non-HFE genes associated with iron homeostasis will enhance our diagnostic certainty of primary haemochromatosis and may explain the variable expression seen in HFE-related disease. Improving our understanding of the mechanisms of iron regulation may lead to novel therapeutic strategies for the management of iron overload.

A Toll-like receptor 7 single nucleotide polymorphism protects from advanced inflammation and fibrosis in male patients with chronic HCV-infection

BACKGROUND/AIMS

HCV-infection leads to development of liver fibrosis, causing morbidity and mortality. Multiple factors influence the progression of fibrosis, including genetic factors. Since HCV is an RNA virus, a role for TLR7 in the immune response against HCV is likely. No systematic analysis of TLR7 single nucleotide polymorphisms (SNPs) has been published.

METHODS

We sequenced TLR7 in 52 women and investigated SNPs with an allele frequency >5% in 807 patients with chronic HCV-infection by melting curve analysis. We analyzed the effect of TLR7 SNPs on grade of inflammation and stage of fibrosis as determined by liver biopsy.

RESULTS

We detected five TLR7 SNPs, three of which showed a frequency >5%. One variant, c.1-120T>G, was more common in patients with no or little inflammation than in patients with grades 2-4 (10.7% vs. 6.1%; P=0.034). The variant was also enriched in patients with no or little fibrosis compared to those with higher stages (12.6% vs. 6.6%; P=0.005). The difference was fully attributable to male patients.

CONCLUSIONS

This is the first analysis of TLR7 SNPs in patients with chronic HCV-infection. Our data suggest that the c.1-120G TLR7 allele offers protection from the development of inflammation and fibrosis in male patients with chronic HCV-infection.

Expression of the subgenomic hepatitis C virus replicon alters iron homeostasis in Huh7 cells

BACKGROUND/AIMS

Infection with hepatitis C virus (HCV) is associated with alterations in body iron homeostasis by poorly defined mechanisms. To seek for molecular links, we employed an established cell culture model for viral replication, and assessed how the expression of an HCV subgenomic replicon affects iron metabolism in host Huh7 hepatoma cells.

METHODS

The expression of iron metabolism genes and parameters defining the cellular iron status were analyzed and compared between parent and replicon Huh7 cells.

RESULTS

By using the IronChip microarray platform, we observed replicon-induced changes in expression profiles of iron metabolism genes. Notably, ceruloplasmin mRNA and protein expression were decreased in replicon cells. In addition, transferrin receptor 1 (TfR1) was also downregulated, while ferroportin levels were elevated, resulting in reduced iron uptake and increased iron release capacity of replicon cells. These responses were associated with an iron-deficient phenotype, manifested in decreased levels of the "labile iron pool" and concomitant induction of IRE-binding activity and IRP2 expression. Furthermore, hemin-treated replicon cells exhibited a defect in retaining iron. The clearance of the replicon by prolonged treatment with interferon-alpha only partially reversed the iron-deficient phenotype but almost completely restored the capacity of cured cells to retain iron.

CONCLUSIONS

We propose that Huh7 cells undergo genetic reprogramming to permit subgenomic viral replication that results in reduction of intracellular iron levels. This response may provide a mechanism to bypass iron-mediated inactivation of the viral RNA polymerase NS5B.

Liver iron is a surrogate marker of severe fibrosis in chronic hepatitis C

BACKGROUND/AIMS

Patients with chronic hepatitis C have frequently mild to moderate liver iron overload which increases with fibrosis stage. Thus, it has been postulated that iron could enhance the progression of fibrosis. However, the real impact of iron is still controversial. The study was undertaken to determine the effect of confounding variables. All factors known to influence both iron overload and fibrosis were taken into account.

METHODS

Five hundred and eighty-six patients, who had liver biopsy performed prior to antiviral treatment, were included. Serum ferritin and liver iron were correlated with clinical, biological and histological variables in univariate and multivariate analysis. The impact of iron on fibrosis was evaluated in multivariate analysis in the whole group and in the subgroup of 380 patients with available date of infection.

RESULTS

Hyperferritinemia, encountered in 27%, was associated with liver iron deposits in only 46% of cases. Liver iron was elevated in 17%, and correlated with age, male sex, and alcohol intake. The univariate strong link which existed between liver iron and fibrosis disappeared after adjustment for confounding variables.

CONCLUSIONS

According to the results of this study, liver iron should be considered more as a surrogate marker for disease severity than as a fibrogenic factor per se.

Restriction of dietary calories, fat and iron improves non-alcoholic fatty liver disease

BACKGROUND

The pathogenesis of non-alcoholic steatohepatitis (NASH) is unclear. Recent studies suggested that oxidative stress plays an important role in the mechanism of NASH. Excessive accumulation of iron in the liver causes oxidative stress. The aim of the present study was to evaluate the grade of hepatic iron accumulation and the therapeutic response to restriction of calories, fat and iron in patients with non-alcoholic fatty liver disease (NAFLD).

METHODS

Twenty-seven NAFLD patients were enrolled. The patients were categorized into two groups: 17 patients with NASH and 10 with simple steatosis. Twelve NAFLD patients (NASH, n = 9; simple steatosis, n = 3) were given a dietary prescription including restriction of energy, fat and iron.

RESULTS

Positive iron staining was observed in 71% and 50% of patients with NASH and simple steatosis, respectively. The average energy intake, fat energy fraction and iron intake decreased significantly 6 months after the beginning of the diet in all patients. In addition, the levels of serum transaminase and ferritin were significantly decreased.

CONCLUSION

Dietary restriction of calories, fat and iron improved NAFLD. Reduced serum ferritin levels appear to reduce oxidative stress in the liver.

Serum measures of iron status and HFE gene mutations in patients with hepatitis B virus infection

AIM

We tested associations between HFE mutations and hepatitis B virus (HBV) infection. We also explored measures of total body iron status and their association with chronic HBV infection.

METHODS

Serum measures of iron status and HFE mutations (C282Y, H63D, and S65C) were assessed in 344 Iranian patients with chronic HBV infection (214 asymptomatic carriers, 130 patients with chronic progressive liver disease [CPLD]) and 302 controls.

RESULTS

Frequencies of HFE mutations did not differ between patients with chronic HBV infection and controls (C282Y: P=0.9, H63D: P= 0.8, S65C: P=0.9). By logistic regression, advanced hepatic fibrosis was associated with HFE H63D mutation (OR=13.1, P=0.006; 95% CI=2.0-84.1). Higher levels of serum ferritin and transferrin saturation were observed in patients with CPLD than in healthy controls (P=0.0001 and 0.01, respectively, adjusted for age and sex). None of the serum iron measures was related to liver fibrosis stage or necroinflammatory grade.

CONCLUSION

Serum iron measures are associated with chronic progressive hepatitis B. Carriage of HFE mutations is not associated with the presence of chronic HBV infection or values of serum iron measures in this population, although HFE H63D is associated with more advanced hepatic fibrosis.

Iron Causes Interactions of TAK1, p21ras, and Phosphatidylinositol 3-Kinase in Caveolae to Activate IκB Kinase in Hepatic Macrophages

We recently discovered a novel signaling phenomenon involving a rapid and transient rise in intracellular low molecular weight iron complex(es) in activation of IkappaB kinase (IKK) in hepatic macrophages. We also showed direct treatment with ferrous iron substitutes for this event to activate IKK. The present study used this model to identify upstream kinases responsible for IKK activation. IKK activation induced by iron is abrogated by overexpression of a dominant negative mutant (DN) for transforming growth factor beta-activated kinase-1 (TAK1), NF-kappaB-inducing kinase, or phosphatidylinositol 3-kinase (PI3K) and by treatment with the mitogen-activated protein kinase (MAPK) kinase-1 (MEK1) inhibitor. Iron increases AKT phosphorylation that is prevented by DNTAK1 or DNp21ras. Iron causes ERK1/2 phosphorylation that is attenuated by DN-PI3K, prevented by DNp21ras, but unaffected by DNTAK1. Iron-induced TAK1 activity is not affected by the PI3K or MEK1 inhibitor, suggesting TAK1 is upstream of PI3K and MEK1. Iron increases interactions of TAK1 and PI3K with p21ras as demonstrated by co-immunoprecipitation and co-localization of these proteins with caveolin-1 as shown by immunofluorescent microscopy. Finally, filipin III, a caveolae inhibitor, abrogates iron-induced TAK1 and IKK activation. In conclusion, MEK1, TAK1, NF-kappa-inducing kinase, and PI3K are required for iron-induced IKK activation in hepatic macrophages and TAK1, PI3K, and p21ras physically interact in caveolae to initiate signal transduction.