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1.
Patients with chronic hepatitis C frequently have serum and hepatic iron overload, but the mechanism is unknown. Recently identified hepcidin, exclusively synthesized in the liver, is thought to be a key regulator for iron homeostasis and is induced by infection and inflammation. This study was conducted to determine the hepatic hepcidin expression levels in patients with various liver diseases. We investigated hepcidin mRNA levels of liver samples by real-time detection-polymerase chain reaction; 56 were hepatitis C virus (HCV) positive, 34 were hepatitis B virus (HBV) positive, and 42 were negative for HCV and HBV (3 cases of auto-immune hepatitis, 7 alcoholic liver disease, 13 primary biliary cirrhosis, 9 nonalcoholic fatty liver disease, and 10 normal liver). We analyzed the relation of hepcidin to clinical, hematological, histological, and etiological findings. Hepcidin expression levels were strongly correlated with serum ferritin (P < 0.0001) and the degree of iron deposit in liver tissues (P < 0.0001). Hepcidin was also correlated with hematological parameters (vs. hemoglobin, P = 0.0073; vs. serum iron, P = 0.0012; vs. transferrin saturation, P < 0.0001) and transaminase levels (P = 0.0013). The hepcidin-to-ferritin ratio was significantly lower in HCV(+) patients than in HBV(+) patients (P = 0.0129) or control subjects (P = 0.0080). In conclusion, hepcidin expression levels in chronic liver diseases were strongly correlated with either the serum ferritin concentration or degree of iron deposits in the liver. When adjusted by either serum ferritin values or hepatic iron scores, hepcidin indices were significantly lower in HCV(+) patients than in HBV(+) patients, suggesting that hepcidin may play a pivotal role in the pathogenesis of iron overload in patients with chronic hepatitis C.  相似文献   

2.
Hepcidin is a key iron-regulatory hormone, the production of which is controlled by iron stores, inflammation, hypoxia and erythropoiesis. The regulation of iron by hepcidin is of clinical importance in thalassemia patients in which anemia occurs along with iron overload. The present study aimed to evaluate the correlation between serum hepcidin and ferritin levels in thalassemia patients. This cross-sectional study investigated 64 patients with thalassemia; 16 β-thalassemia major (BTM), 31 β-thalassemia/hemoglobin (Hb) E (BE), and 17 Hb H + AE Bart’s disease (Hb H + AE Bart’s). The levels of serum hepcidin and ferritin, and Hb of the three groups were measured. The median values of serum ferritin and Hb were significantly different among the three groups, whereas serum hepcidin values were not observed to be significantly different. The correlation of the serum hepcidin and ferritin levels was not statistically significant in any of the three groups of thalassemia patients with BTM, BE, or Hb H + AE Bart’s (r = −0.141, 0.065 and −0.016, respectively). In conclusion, no statistically significant correlations were observed between serum hepcidin with any variables including serum ferritin, Hb, age, labile plasma iron (LPI), and number of blood transfusion units among the three groups of thalassemia patients. Likely, the regulation of hepcidin in thalassemia patients is affected more by erythropoietic activity than iron storage.  相似文献   

3.
This paper is dedicated to the memory of our wonderful colleague Professor Alfredo Colonna, who passed away the same day of its acceptance. Fatty liver accumulation, inflammatory process and insulin resistance appear to be crucial in non-alcoholic fatty liver disease (NAFLD), nevertheless emerging findings pointed an important role also for iron overload. Here, we investigate the molecular mechanisms of hepatic iron metabolism in the onset of steatosis to understand whether its impairment could be an early event of liver inflammatory injury. Rats were fed with control diet or high fat diet (HFD) for 5 or 8 weeks, after which liver morphology, serum lipid profile, transaminases levels and hepatic iron content (HIC), were evaluated. In liver of HFD fed animals an increased time-dependent activity of iron regulatory protein 1 (IRP1) was evidenced, associated with the increase in transferrin receptor-1 (TfR1) expression and ferritin down-regulation. Moreover, ferroportin (FPN-1), the main protein involved in iron export, was down-regulated accordingly with hepcidin increase. These findings were indicative of an increased iron content into hepatocytes, which leads to an increase of harmful free-iron also related to the reduction of hepatic ferritin content. The progressive inflammatory damage was evidenced by the increase of hepatic TNF-α, IL-6 and leptin, in parallel to increased iron content and oxidative stress. The major finding that emerged of this study is the impairment of iron homeostasis in the ongoing and sustaining of liver steatosis, suggesting a strong link between iron metabolism unbalance, inflammatory damage and progression of disease.  相似文献   

4.
Anemia of inflammation in patients with acute or chronic acute-phase activation is a common clinical problem. Hepcidin is a peptide shown to be the principal regulator of the absorption and systemic distribution of iron. Main inducers of hepcidin are iron overload, hypoxia and inflammation, where the latter has been linked to hepcidin via increased interleukin-6 (IL-6). This article addresses the impact and time course of postoperative acute-phase reaction in humans following heart surgery on prohepcidin, hepcidin, hematological markers and IL-6 concentrations. Serum concentrations of prohepcidin, hepcidin, IL-6 and hematological iron parameters were studied in five male patients without infection before and after heart surgery. This study, which is the first to report the impact on serum hepcidin and serum prohepcidin concentrations in patients following surgery, clearly demonstrates the induction of hypoferremia due to the postoperative acute-phase reaction. Significant changes were seen for serum iron concentration, transferrin saturation, total iron binding capacity and hemoglobin concentration. A significant increase in ferritin concentration was seen 96-144 h postoperatively. Additionally, there were significant alterations in both serum hepcidin after 96-144 h and serum prohepcidin after 48 h compared with preoperative values. Serum prohepcidin decreased, whereas serum hepcidin increased. In conclusion, changes in serum prohepcidin were followed by an increase in serum hepcidin. This speaks in favor of a chain of action where proteolytic trimming of serum prohepcidin results in increased serum hepcidin. However, hypoferremia appeared prior to the changes in serum prohepcidin and serum hepcidin.  相似文献   

5.
Venesection has been proposed as a treatment for hepatic iron overload in a number of chronic liver disorders that are not primarily linked to mutations in iron metabolism genes. Our aim was to analyse the impact of venesection on iron mobilisation in a mouse model of secondary iron overload. C57Bl/6 mice were given oral iron supplementation with or without phlebotomy between day 0 (D0) and D22, and the results were compared to controls without iron overload. We studied serum and tissue iron parameters, mRNA levels of hepcidin1, ferroportin, and transferrin receptor 1, and protein levels of ferroportin in the liver and spleen. On D0, animals with iron overload displayed elevations in iron parameters and hepatic hepcidin1 mRNA. By D22, in the absence of phlebotomies, splenic iron had increased, but transferrin saturation had decreased. This was associated with high hepatic hepcidin1 mRNA, suggesting that iron bioavailability decreased due to splenic iron sequestration through ferroportin protein downregulation. After 22 days with phlebotomy treatments, control mice displayed splenic iron mobilisation that compensated for the iron lost due to phlebotomy. In contrast, phlebotomy treatments in mice with iron overload caused anaemia due to inadequate iron mobilisation. In conclusion, our model of secondary iron overload led to decreased plasma iron associated with an increase in hepcidin expression and subsequent restriction of iron export from the spleen. Our data support the importance of managing hepcidin levels before starting venesection therapy in patients with secondary iron overload that are eligible for phlebotomy.  相似文献   

6.
7.
Hepatitis C virus (HCV) infection is a leading cause of liver-related mortality. Chronic hepatitis C (CHC) is frequently associated with disturbances in iron homeostasis, with serum iron and hepatic iron stores being elevated. Accumulating evidence indicates that chronic HCV infection suppresses expression of hepatic hepcidin, a key mediator of iron homeostasis, leading to iron overload conditions. Since hepcidin mediates degradation of ferroportin, a basolateral transporter involved in the release of iron from cells, diminished hepcidin expression probably leads to up-regulation of ferroportin-1 (Fpn1) in patients with CHC. In this study, we determined the protein levels of duodenal Fpn1, and found that its expression was significantly up-regulated in patients with CHC. The expression of duodenal Fpn1 is negatively correlated with mRNA levels of hepcidin, and positively correlated with serum iron parameters. Although iron is a critical factor for growth of a variety of pathogenic bacteria, our results suggest that iron overload in blood does not increase the infection rate of bacteria in patients with CHC.  相似文献   

8.
High levels of iron, measured as serum ferritin, are associated to a worse outcome after stroke. However, it is not known whether ischemic damage might increase ferritin levels as an acute phase protein or whether iron overload affects stroke outcome. The objectives are to study the effect of stroke on serum ferritin and the contribution of iron overload to ischemic damage.  相似文献   

9.
10.
High levels of iron, measured as serum ferritin, are associated to a worse outcome after stroke. However, it is not known whether ischemic damage might increase ferritin levels as an acute phase protein or whether iron overload affects stroke outcome. The objectives are to study the effect of stroke on serum ferritin and the contribution of iron overload to ischemic damage.Swiss mice were fed with a standard diet or with a diet supplemented with 2.5% carbonyl iron to produce iron overload. Mice were submitted to permanent (by ligature and by in situ thromboembolic models) or transient focal ischemia (by ligature for 1 or 3 h).Treatment with iron diet produced an increase in the basal levels of ferritin in all the groups. However, serum ferritin did not change after ischemia. Animals submitted to permanent ischemia had the same infarct volume in the groups studied. However, in mice submitted to transient ischemia followed by early (1 h) but not late reperfusion (3 h), iron overload increased ischemic damage and haemorrhagic transformation.Iron worsens ischemic damage induced by transient ischemia and early reperfusion. In addition, ferritin is a good indicator of body iron levels but not an acute phase protein after ischemia.  相似文献   

11.
The use of iron supplements should be a judicious choice, primarily when considering the possible risks deriving from an unjustified treatment. In trained athletes, levels of ferritin between 15 and 30 microg/L are frequently observed. Within this ferritin range, the usefulness of iron supplementation is still controversial. The aim of the present study is to evaluate the clinical usefulness of hepcidin assessment in the analysis of the iron status of young non-anemic athletes. Fifty young athletes were enrolled. The subjects were divided into 4 groups according to their ferritin levels. No statistically significant difference was found regarding hepcidin levels between athletes with ferritin lower than 15 microg/L and those in the 15-30 microg/L range. Similarly, no difference was found between athletes with ferritin higher than 50 microg/L and those in the 30-50 microg/L range. On the contrary, statistically significant differences were found between athletes with ferritin levels ranging from 15 to 30 microg/L and those in the 30-50 microg/L range. The present study suggests that serum ferritin levels below 30 microg/L indicate an asymptomatic iron deficiency status inhibiting hepcidin expression and that 30 microg/L should be considered the ferritin cut-off when considering an iron supplementation in young athletes.  相似文献   

12.

Purpose

Excessive brain iron accumulation contributes to cognitive impairments in hepatitis B virus (HBV)-related cirrhotic patients. The underlying mechanism remains unclear. Hepcidin, a liver-produced, 25-aminoacid peptide, is the major regulator of systemic iron metabolism. Abnormal hepcidin level is a key factor in some body iron accumulation or deficiency disorders, especially in those associated with liver diseases. Our study was aimed to explore the relationship between brain iron content in patients with HBV-related cirrhosis and serum hepcidin level.

Methods

Seventy HBV-related cirrhotic patients and forty age- sex-matched healthy controls were enrolled. Brain iron content was quantified by susceptibility weighted phase imaging technique. Serum hepcidin as well as serum iron, serum transferrin, ferritin, soluble transferrin receptor, total iron binding capacity, and transferrin saturation were tested in thirty cirrhotic patients and nineteen healthy controls. Pearson correlation analysis was performed to investigate correlation between brain iron concentrations and serum hepcidin, or other iron parameters.

Results

Cirrhotic patients had increased brain iron accumulation compared to controls in the left red nuclear, the bilateral substantia nigra, the bilateral thalamus, the right caudate, and the right putamen. Cirrhotic patients had significantly decreased serum hepcidin concentration, as well as lower serum transferring level, lower total iron binding capacity and higher transferrin saturation, compared to controls. Serum hepcidin level negatively correlated with the iron content in the right caudate, while serum ferritin level positively correlated with the iron content in the bilateral putamen in cirrhotic patients.

Conclusions

Decreased serum hepcidin level correlated with excessive iron accumulation in the basal ganglia in HBV-related cirrhotic patients. Our results indicated that systemic iron overload underlined regional brain iron repletion. Serum hepcidin may be a clinical biomarker for brain iron deposition in cirrhotic patients, which may have therapeutic potential.  相似文献   

13.
Although the recent identification of several genes has extended our knowledge on the maintenance of body iron homeostasis, their tissue specific expression patterns and the underlying regulatory networks are poorly understood. We studied C57black/Sv129 mice and HFE knockout (HFE -/-) variants thereof as a model for hemochromatosis, and investigated the expression of iron metabolism genes in the duodenum, liver, and kidney as a function of dietary iron challenge. In HFE +/+ mice dietary iron supplementation increased hepatic expression of hepcidin which was paralleled by decreased iron regulatory protein (IRP) activity, and reduced expression of divalent metal transporter-1 (DMT-1) and duodenal cytochrome b (Dcytb) in the enterocyte. In HFE -/- mice hepcidin formation was diminished upon iron challenge which was associated with decreased hepatic transferrin receptor (TfR)-2 levels. Accordingly, HFE -/- mice presented with high duodenal Dcytb and DMT-1 levels, and increased IRP and TfR expression, suggesting iron deficiency in the enterocyte and increased iron absorption. In parallel, HFE -/- resulted in reduced renal expression of Dcytb and DMT-1. Our data suggest that the feed back regulation of duodenal iron absorption by hepcidin is impaired in HFE -/- mice, a model for genetic hemochromatosis. This change may be linked to inappropriate iron sensing by the liver based on decreased TfR-2 expression, resulting in reduced circulating hepcidin levels and an inappropriate up-regulation of Dcytb and DMT-1 driven iron absorption. In addition, iron excretion/reabsorption by the kidneys may be altered, which may aggravate progressive iron overload.  相似文献   

14.
Patients with alcoholic liver disease (ALD) often display disturbed iron indices. Hepcidin, a key regulator of iron metabolism, has been shown to be down‐regulated by alcohol in cell lines and animal models. This down‐regulation led to increased duodenal iron transport and absorption in animals. In this study, we investigated gene expression of duodenal iron transport molecules and hepcidin in three groups of patients with ALD (with anaemia, with iron overload and without iron overload) and controls. Expression of DMT1, FPN1, DCYTB, HEPH, HFE and TFR1 was measured in duodenal biopsies by using real‐time PCR and Western blot. Serum hepcidin levels were measured by using ELISA. Serum hepcidin was decreased in patients with ALD. At the mRNA level, expressions of DMT1, FPN1 and TFR1 genes were significantly increased in ALD. This pattern was even more pronounced in the subgroups of patients without iron overload and with anaemia. Protein expression of FPN1 paralleled the increase at the mRNA level in the group of patients with ALD. Serum ferritin was negatively correlated with DMT1 mRNA. The down‐regulation of hepcidin expression leading to up‐regulation of iron transporters expression in the duodenum seems to explain iron metabolism disturbances in ALD. Alcohol consumption very probably causes suppression of hepcidin expression in patients with ALD.  相似文献   

15.
Iron overload toxicity was shown to associate with chronic liver diseases which lead to hepatic fibrosis and subsequently the progression to cancer through oxidative stress and apoptotic pathways. Green tea potential activity as chelating, anti-oxidative, or anti-apoptotic mechanisms against metal toxicity was poorly clarified. Here, we are trying to evaluate the anti-oxidant and anti-apoptotic properties of green tea in the regulation of serum hepcidin levels, reduction in iron overloads, and improve of liver fibrosis in iron overloaded experimental rats. Three groups of male adult rats were randomly classified into three groups and treated as follows: control rats, iron treated rats for two months in drinking water followed by either vehicle or green tea extract (AGTE; 100 mg/kg) treatment for 2 more months. Thereafter, we studied the effects of AGTE on iron overload-induced lipid peroxidation, anti-oxidant depletion, liver cell injury and apoptosis. Treatment of iron-overloaded rats with AGTE resulted in marked decreases in iron accumulation within liver, depletion in serum ferritin, and hepcidin levels. Iron-overloaded rats had significant increase in malonyldialdehyde (MDA), a marker of lipid peroxidation and nitric oxide (NO) in liver when compared to control group. Also, significant change in cytochrome c and DNA content as apoptotic markers were reported in iron treated rats. The effects of iron overload on lipid peroxidation, NO levels, cytochrome c and DNA content were significantly reduced by the intervention treatment with AGTE (P < 0.001). Furthermore, the endogenous anti-oxidant capacities/levels (TAC) in liver were also significantly decreased in chronic iron overload and administration of AGTE restored the decrease in the hepatic antioxidant activities/levels. Also, hepatic hepcidin was shown to be significantly correlated with oxidative and apoptotic relating biomarkers as well as an improvement in liver fibrosis of iron treated rats following AGTE treatment. In-vitro analysis showed that, the improvement in iron toxicity of the liver depend mainly on antioxidant and protective ability of green tea polyphenolic compounds especiallyepigallocatechin-3-gallate (EGCG). Our study showed that green tea extract (GTE) ameliorates iron overload induced hepatotoxicity, apoptosis and oxidative stress in rat liver via inhibition of hepatic iron accumulation; improve of liver antioxidant capacity, and down regulation of serum hepcidin as well as reduction in the release of apoptotic relating proteins.  相似文献   

16.
174 serum ferritin assays in 121 patients with various haemolytic disorders have been performed. The mean serum ferritin levels were significantly increased in all these disorders in contrast to healthy controls. The highest serum ferritin levels were found in pyruvate kinase (PK) deficiency, moderate increase was observed in hereditary sphaerocytosis (HS) and in autoimmune haemolytic anaemia (AIHA) with massive haemolysis and in glucose-6-phosphate dehydrogenase (G-6-PD) deficiency. Mild elevation of serum ferritin levels was depicted in paroxysmal nocturnal haemoglobinuria (PNH), in beta thalassaemia minor and in other types of haemoglobinopathies. The range of values was associated with a degree of haemolysis and its relation to duration of the disease was not apparent in most cases. Highly significant differences between serum ferritin levels in splenectomized and non-splenectomized patients with HS and between serum ferritin levels in patients with AIHA with massive haemolysis or in remission were found. As compared to normal controls, significant increase of serum ferritin levels was observed even in patients with AIHA in remission or in splenectomized patients with HS. In two patients with PK deficiency the levels exceeding 2,000 micrograms/l indicated manifest iron overload. A reliability of serum ferritin assay as an index of iron stores in haemolytic disorders has been discussed.  相似文献   

17.
Genetic variants associated with iron homeostasis have been identified, but their association with iron-related indices and variables among different ethnic populations remains controversial. We aimed to explore the genotype frequency and allelic distribution of three iron-metabolism related variants in homeostatic iron regulator gene (HFE; rs1800562 G/A), transmembrane protease, Serine-6 gene (TMPRSS6; rs855791 A/G), and BTB domain-containing protein-9 gene (BTBD9; rs9357271 C/T) among a sample of the Middle Eastern blood donors and to detect the association of these variants on blood indices, and serum hepcidin/ferritin levels. Real-Time TaqMan genotyping assay for the specified variants was applied for 197 unrelated blood donors. Complete blood picture and serum hepcidin/ferritin levels were assessed. All participants were carriers of rs1800562*G/G genotype for HFE. The frequency of A/A and A/G genotypes of TMPRSS6 rs855791 variant was 55% and 45%, and for C/C, C/T, and T/T of BTBD9 rs9357271, were 15%, 43%, and 42%, respectively. Minor allele frequencies of rs855791*G and rs9357271*C were 0.23 and 0.37. The GGC genotype combination (for HFE/TMPRSS6/BTBD9, respectively) was more frequent in male participants. Higher serum hepcidin and hepcidin/ferritin ratio were observed in TMPRSS6 (A/G) carriers. While subjects with BTBD9 C/T and TT genotypes had lower serum ferritin values and higher levels of hepcidin and hepcidin/ferritin ratio compared with C/C genotype. No significant associations were found with any other blood parameters.In conclusion, TMPRSS6 rs855791 (A/G) and BTBD9 rs9357271 (C/T) variants were prevalent in the present blood donor population and may influence the serum hepcidin and/or ferritin levels.  相似文献   

18.
Hepcidin, a liver hormone, is important for both innate immunity and iron metabolism regulation. As dysfunction of the hepcidin pathway may contribute to liver pathology, we analysed liver hepcidin mRNA and serum hepcidin in patients with chronic liver diseases. Hepcidin mRNA levels were determined in liver biopsies obtained from 126 patients with HCV (n = 21), HBV (n = 23), autoimmune cholestatic disease (primary biliary cirrhosis and primary sclerosing cholangitis; PBC/PSC; n = 34), autoimmune hepatitis (AIH; n = 16) and non-alcoholic fatty liver disease (NAFLD; n = 32). Sera sampled on the biopsy day from the same patients were investigated for serum hepcidin levels. Hepatic hepcidin mRNA levels correlated positively with ferritin and negatively with serum γ-GT levels. However, no correlation was found between serum hepcidin and either ferritin or liver hepcidin mRNA. Both serum hepcidin and the serum hepcidin/ferritin ratio were significantly lower in AIH and PBC/PSC patients’ sera compared to HBV, HCV or NAFLD (P<0.001 for each comparison) and correlated negatively with serum ALP levels. PBC/PSC and AIH patients maintained low serum hepcidin during the course of their two-year long treatment. In summary, parallel determination of liver hepcidin mRNA and serum hepcidin in patients with chronic liver diseases shows that circulating hepcidin and its respective ratio to ferritin are significantly diminished in patients with autoimmune liver diseases. These novel findings, once confirmed by follow-up studies involving bigger size and better-matched disease subgroups, should be taken into consideration during diagnosis and treatment of autoimmune liver diseases.  相似文献   

19.
OBJECTIVE: To analyze the secretion of the insulin precursor proinsulin in patients with beta-thalassemia and its possible relation to iron overload. METHODS: We assessed fasting proinsulin, insulin, C-peptide and glucose levels from 34 patients with beta-thalassemia and 33 healthy controls. The correlation to age, body mass index, hepatic iron concentration, serum ferritin and serum AST was analyzed. RESULTS: Fasting proinsulin (p < 0.002) and proinsulin-to-insulin ratio (p < 0.02) were significantly increased in patients with thalassemia irrespective of the degree of glucose tolerance. They correlated positively to serum ferritin, liver iron, patient age and serum AST (all p < 0.05). CONCLUSIONS: Disproportionately elevated proinsulin levels in thalassemic patients indicate early beta-cell dysfunction due to siderosis. An additional biological significance of hyperproinsulinemia and its possible ability to predict long-term iron toxicity in these patients remain to be clarified.  相似文献   

20.
Hepcidin has been implicated as the iron stores regulator: a hepatic signaling molecule that regulates intestinal iron absorption by undefined mechanisms. The possibility that hepcidin regulates the expression of ferroportin 1 (FPT1), the basolateral iron transporter, was examined in rats after administration of LPS, an iron chelator, or His-tagged recombinant hepcidin (His-rHepc). In the liver, LPS stimulated a biphasic increase of hepcidin mRNA with peaks of mRNA at 6 and 36 h. Concurrently, hepatic FPT1 mRNA expression decreased to minimal level at 6 h and then increased with a peak at 24-36 h. LPS also induced biphasic changes in intestinal FPT1 mRNA expression, with decreased levels at 6 h and increased expression at 48 h. Whereas the initial decrease of FPT1 coincides with an LPS-induced decrease in serum iron, both intestinal and hepatic FPT1 expression recovered, whereas serum iron concentration continued to decrease for at least 24 h. Dietary iron ingestion increased intestinal ferritin protein production but did not reduce intestinal FPT1 mRNA expression. The iron chelator pyrrolidinedithiocarbamate (PDTC) stimulated hepatic hepcidin without suppressing intestinal FPT1 expression. In PDTC-treated rats, LPS stimulated no additional hepatic hepcidin expression but did increase intestinal FPT1 expression. Administration of HisrHepc induced significant reduction of intestinal FPT1 expression. Taken together, these data suggest that hepcidin mediates LPS-induced downregulation of intestinal FPT1 expression and that the hepcidin signaling pathway involves a PDTC-sensitive step.  相似文献   

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