Role of iron in hepatic fibrosis: One piece in the puzzle

Difference in the Mechanism of Iron Overload-Enhanced Acute Hepatotoxicity Induced by Thioacetamide and Carbon Tetrachloride in Rats

Iron overload has been recognized as a risk factor for liver disease; however, little is known about its pathological role in the modification of liver injury. The purpose of this study is to investigate the influence of iron overload on liver injury induced by two hepatotoxicants with different pathogenesis in rats. Rats were fed a control (Cont), 0.8% high-iron (0.8% Fe), or 1% high-iron diet (1% Fe) for 4 weeks and were then administered with saline, thioacetamide (TAA), or carbon tetrachloride (CCl4). Hepatic and systemic iron overload were seen in the 0.8% and 1% Fe groups. Twenty-four hours after administration, hepatocellular necrosis induced by TAA and hepatocellular necrosis, degeneration, and vacuolation induced by CCl4, as well as serum transaminase values, were exacerbated in the 0.8% and 1% Fe groups compared to the Cont group. On the other hand, microvesicular vacuolation induced by CCl4 was decreased in 0.8% and 1% Fe groups. Hepatocellular DNA damage was increased by iron overload in both models, whereas a synergistic effect of oxidative stress by excess iron and hepatotoxicant was only present in the CCl4 model. The data showed that dietary iron overload exacerbates TAA- and CCl4-induced acute liver injury with different mechanisms.

Hyperferritinemia and liver iron content determined with MRI: Reintroduction of the liver iron index

BACKGROUND

Hyperferritinemia is found in around 12 % of the general population. Analyzing the cause can be difficult. In case of doubt about the presence of major iron overload most guidelines advice to perform a MRI as a reliable non-invasive marker to measure liver iron concentration (LIC). In general, a LIC of ≥ 36 µmol/g dw is considered the be elevated however in hyperferritinemia associated with, for example, obesity or alcohol (over)consumption the LIC can be ≥ 36 µmol/g dw in abscence of major iron overload. So, unfortunately a clear cut-off value to differentiate iron overload from normal iron content is lacking. Previously the liver iron index (LII) (LIC measured in liver biopsy (LIC-b)/age (years)), was introduced to differentiate between patients with major (LII ≥ 2) and minor or no iron overload (LII < 2). Based on the good correlation between the LIC-b and LIC determined with MRI (LIC-MRI), our goal was to investigate whether a LII_MRI ≥ 2 is a good indicator of major iron overload, reflected by a significantly higher amount of iron needed to be mobilized to reach iron depletion.

METHODS

We compared the amount of mobilized iron to reach depletion and inflammation-related characteristics in two groups: LII-MRI ≥ 2 versus LII-MRI <2 in 92 hyperferritinemia patients who underwent HFE genotyping and MRI-LIC determination.

RESULTS

Significantly more iron needed to be mobilized to reach iron depletion in the LII ≥ 2 group (mean 4741, SD ± 4135 mg) versus the LII-MRI <2 group (mean 1340, SD ± 533 mg), P < 0.001. Furthermore, hyperferritinemia in LII-MRI < 2 patients was more often related to components of the metabolic syndrome while hyperferritinemia in LII-MRI ≥ 2 patients was more often related to HFE mutations. ROC curve analysis showed good performance of LII =2 as cut-off value. However the calculations showed that the optimal cut-off for the LII = 3.4.

CONCLUSION

The LII-MRI with a cut-off value of 2 is an effective method to differentiate major from minor iron overload in patients with hyperferritinemia. But the LII-MRI = 3.4 seems a more promising diagnostic test for major iron overload.

Liver Iron Loading in Alcohol-Associated Liver Disease

Alcohol-associated liver disease (ALD) is a common chronic liver disease with increasing incidence worldwide. Alcoholic liver steatosis/steatohepatitis can progress to liver fibrosis/cirrhosis, which can cause predisposition to hepatocellular carcinoma. ALD diagnosis and management are confounded by several challenges. Iron loading is a feature of ALD which can exacerbate alcohol-induced liver injury and promote ALD pathologic progression. Knowledge of the mechanisms that mediate liver iron loading can help identify cellular/molecular targets and thereby aid in designing adjunct diagnostic, prognostic, and therapeutic approaches for ALD. Herein, the cellular mechanisms underlying alcohol-induced liver iron loading are reviewed and how excess iron in patients with ALD can promote liver fibrosis and aggravate disease pathology is discussed. Alcohol-induced increase in hepatic transferrin receptor-1 expression and up-regulation of high iron protein in Kupffer cells (proposed) facilitate iron deposition and retention in the liver. Iron is loaded in both parenchymal and nonparenchymal liver cells. Iron-loaded liver can promote ferroptosis and thereby contribute to ALD pathology. Iron and alcohol can independently elevate oxidative stress. Therefore, a combination of excess iron and alcohol amplifies oxidative stress and accelerates liver injury. Excess iron-stimulated hepatocytes directly or indirectly (through Kupffer cell activation) activate the hepatic stellate cells via secretion of proinflammatory and profibrotic factors. Persistently activated hepatic stellate cells promote liver fibrosis, and thereby facilitate ALD progression.

QSM Throughout the Body

Magnetic materials in tissue, such as iron, calcium, or collagen, can be studied using quantitative susceptibility mapping (QSM). To date, QSM has been overwhelmingly applied in the brain, but is increasingly utilized outside the brain. QSM relies on the effect of tissue magnetic susceptibility sources on the MR signal phase obtained with gradient echo sequence. However, in the body, the chemical shift of fat present within the region of interest contributes to the MR signal phase as well. Therefore, correcting for the chemical shift effect by means of water-fat separation is essential for body QSM. By employing techniques to compensate for cardiac and respiratory motion artifacts, body QSM has been applied to study liver iron and fibrosis, heart chamber blood and placenta oxygenation, myocardial hemorrhage, atherosclerotic plaque, cartilage, bone, prostate, breast calcification, and kidney stone.

Iron overload triggering ECM-mediated Hippo/YAP pathway in follicle development: a hypothetical model endowed with therapeutic implications

Disruption of iron homeostasis plays a negative role in follicle development. The dynamic changes in follicle growth are dependent on Hippo/YAP signaling and mechanical forces. However, little is known about the liaison between iron overload and the Hippo/YAP signalling pathway in term of folliculogenesis. Here, based on the available evidence, we established a hypothesized model linking excessive iron, extracellular matrix (ECM), transforming growth factor-β (TGF-β) and Hippo/Yes-associated protein (YAP) signal regarding follicle development. Hypothetically, the TGF-β signal and iron overload may play a synergistic role in ECM production via YAP. We speculate that the dynamic homeostasis of follicular iron interacts with YAP, increasing the risk of ovarian reserve loss and may enhance the sensitivity of follicles to accumulated iron. Hence, therapeutic interventions targeting iron metabolism disorders, and Hippo/YAP signal may alter the consequences of the impaired developmental process based on our hypothesis, which provides potential targets and inspiration for further drug discovery and development applied to clinical treatment.

Iron as a therapeutic target in chronic liver disease

It was clearly realized more than 50 years ago that iron deposition in the liver may be a critical factor in the development and progression of liver disease. The recent clarification of ferroptosis as a specific form of regulated hepatocyte death different from apoptosis and the description of ferritinophagy as a specific variation of autophagy prompted detailed investigations on the association of iron and the liver. In this review, we will present a brief discussion of iron absorption and handling by the liver with emphasis on the role of liver macrophages and the significance of the iron regulators hepcidin, transferrin, and ferritin in iron homeostasis. The regulation of ferroptosis by endogenous and exogenous mod-ulators will be examined. Furthermore, the involvement of iron and ferroptosis in various liver diseases including alcoholic and non-alcoholic liver disease, chronic hepatitis B and C, liver fibrosis, and hepatocellular carcinoma (HCC) will be analyzed. Finally, experimental and clinical results following interventions to reduce iron deposition and the promising manipulation of ferroptosis will be presented. Most liver diseases will be benefited by ferroptosis inhibition using exogenous inhibitors with the notable exception of HCC, where induction of ferroptosis is the desired effect. Current evidence mostly stems from in vitro and in vivo experimental studies and the need for well-designed future clinical trials is warranted.

Liver injury in COVID-19: Holds ferritinophagy-mediated ferroptosis accountable

Even in patients without a history of liver disease, liver injury caused by coronavirus disease 2019 (COVID-19) is gradually becoming more common. However, the precise pathophysiological mechanisms behind COVID-19's liver pathogenicity are still not fully understood. We hypothesize that inflammation may become worse by cytokine storms caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Elevated ferritin levels can initiate ferritinophagy mediated by nuclear receptor coactivator 4 (NCOA4), which leads to iron elevation, and ferroptosis. In COVID-19 patients, ferroptosis can be restricted to reduce disease severity and liver damage by targeting NCOA4-mediated ferritinophagy. To confirm the role of ferritinophagy-mediated ferroptosis in SARS-CoV-2 infection, further research is required.

Endometriosis Stem Cells as a Possible Main Target for Carcinogenesis of Endometriosis-Associated Ovarian Cancer (EAOC)

Endometriosis is a serious recurrent disease impairing the quality of life and fertility, and being a risk for some histologic types of ovarian cancer defined as endometriosis-associated ovarian cancers (EAOC). The presence of stem cells in the endometriotic foci could account for the proliferative, migrative and angiogenic activity of the lesions. Their phenotype and sources have been described. The similarly disturbed expression of several genes, miRNAs, galectins and chaperones has been observed both in endometriotic lesions and in ovarian or endometrial cancer. The importance of stem cells for nascence and sustain of malignant tumors is commonly appreciated. Although the proposed mechanisms promoting carcinogenesis leading from endometriosis into the EAOC are not completely known, they have been discussed in several articles. However, the role of endometriosis stem cells (ESCs) has not been discussed in this context. Here, we postulate that ESCs may be a main target for the carcinogenesis of EAOC and present the possible sequence of events resulting finally in the development of EAOC.

Ameliorative Effect of Pomegranate Peel Extract (PPE) on Hepatotoxicity Prompted by Iron Oxide Nanoparticles (Fe2O3-NPs) in Mice

An evaluation of the ameliorative effect of pomegranate peel extract (PPE) in counteracting the toxicity of iron oxide nanoparticles (Fe₂O₃-NPs) that cause hepatic tissue damage is focused on herein. Forty male albino mice were haphazardly grouped into four groups as follows: the first control group was orally gavage daily with physiological saline; the second group received 100 mg/kg of PPE by the oral route day after day; the third group received 30 mg/kg Fe₂O₃-NPs orally; and the fourth group received both PPE and Fe₂O₃-NPs by the oral route, the same as the second and third sets. Later, after the completion of the experiment, we collected the liver, blood, and bone marrow of bone specimens that were obtained for further laboratory tests. For instance, exposure to Fe₂O₃-NPs significantly altered serum antioxidant biomarkers by decreasing the levels of total antioxidant capacity (TAC), catalase (CAT), and glutathione s-transferase (GST). Additionally, it caused changes in the morphology of hepatocytes, hepatic sinusoids, and inflammatory Kupffer cells. Furthermore, they significantly elevated the number of chromosomal aberrations including gaps, breaks, deletions, fragments, polyploidies, and ring chromosomes. Moreover, they caused a significant overexpression of TIMP-1, TNF-α, and BAX mRNA levels. Finally, the use of PPE alleviates the toxicity of Fe₂O₃-NPs that were induced in the hepatic tissues of mice. It is concluded that PPE extract has mitigative roles against the damage induced by Fe₂O₃-NPs, as it serves as an antioxidant and hepatoprotective agent. The use of PPE as a modulator of Fe₂O₃-NPs' hepatotoxicity could be considered as a pioneering method in the use of phytochemicals against the toxicity of nanoparticles.

Potential Use of Patient-Specific Induced Pluripotent Stem Cell for Liver Fibrosis Thalassemia Treatment Management

Thalassemia is the most common inherited single gene blood disease worldwide and present a significant health problem in the world. Approximately, 1.5% of the global populations (An estimated 80–90 million people) are carriers of β-thalassemia. Around 5% of Indonesia population is thought to carry the thalassemia gene. The globin imbalance in β-thalassemia major causes hemolysis and ineffective erythropoiesis which results in anemia leading to increases of iron absorption. Furthermore, repeated blood transfusion and long-term increased iron absorption will lead to excessive accumulation of iron in vital organs, especially in the liver, causes liver fibrosis then leading to liver disease. Iron overload can be controlled by iron chelating drugs with the risk of side effects; therefore, a breakthrough is needed. Stem cell technology has a potential to provide novel insight in thalassemia major, through induced pluripotent stem cells (iPSCs) who has the ability to differentiate into hepatic stellate cells (HSCs)-like cells. iPSCs derived HSC-like cells (iPSC-HSCs) present the phenotypic and functional characteristics of HSCs. The utilization of iPSCs is a new option in personalized thalassemia management.

Anti-Oxidant and Anti-Inflammatory Effects of Lipopolysaccharide from Rhodobacter sphaeroides against Ethanol-Induced Liver and Kidney Toxicity in Experimental Rats

This study aimed to investigate the protective effects of lipopolysaccharide from Rhodobacter sphaeroides (LPS-RS) against ethanol-induced hepatotoxicity and nephrotoxicity in experimental rats. The study involved an intact control group, LPS-RS group, two groups were given ethanol (3 and 5 g/kg/day) for 28 days, and two other groups (LPS-RS + 3 g/kg ethanol) and (LPS-RS + 5 g/kg ethanol) received a daily dose of LPS-RS (800 μg/kg) before ethanol. Ethanol significantly increased the expression of nuclear factor kappa B (NF-κB) and levels of malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) in the liver tissue and decreased anti-oxidant enzymes. Hepcidin expression was downregulated in the liver, with increased serum levels of ferritin and iron. Prior-administration of LPS-RS alleviated the increase in oxidative stress and inflammatory markers, and preserved iron homeostasis markers. In the kidney, administration of ethanol caused significant increase in the expression of NF-κB and the levels of TNF-α and kidney injury markers; whereas LPS-RS + ethanol groups had significantly lower levels of those parameters. In conclusion; this study reports anti-oxidant, anti-inflammatory and iron homeostasis regulatory effects of the toll-like receptor 4 (TLR4) antagonist LPS-RS against ethanol induced toxicity in both the liver and the kidney of experimental rats.

Fluorescence-Based Detection of Ferrous Iron in Senescent Cells

A major limitation in aging research is the lack of reliable biomarkers to assess phenotypic changes with age or monitor response to antiaging interventions. This study investigates the role of intracellular ferrous iron (Fe₂⁺) as a potential biomarker of senescence. Iron is known to accumulate in various tissues with age and recent studies have demonstrated that its level increases dramatically in senescent cells. The current techniques used to measure the accumulation of iron are cumbersome and only measure total iron not specific isotopes such as the redox reactive Fe₂⁺. It is still to be determined whether the damaging form of iron (Fe₂⁺) is specifically elevated in senescent cells. In this study, we assessed the potential use of a newly discovered Fe₂⁺ reactive probe (SiRhoNox-1) for selective labeling of senescent cells in vitro. For this we have generated various senescent cell models and subjected them to SiRhoNox-1 labeling. Our results indicate that SiRhoNox-1 selectivity labels live senescent cells and was more specific and faster than current staining such as SA-βGal or a derived fluorescent probe C₁₂FDG. Together these findings suggest that SiRhoNox-1 may serve as a convenient tool to detect senescent cells based on their ferrous iron level.

Oligopeptides from Jinhua ham prevent alcohol-induced liver damage by regulating intestinal homeostasis and oxidative stress in mice

The current study aimed to evaluate the protective activity of peptides isolated from Jinhua ham (JHP) against alcoholic liver disease (ALD) and the mechanisms by which JHP prevents against ALD. The tangential flow filtration (TFF) combined with size exclusion chromatography (SEC) and reversed-phase high performance liquid chromatography (RP-HPLC) were used to isolate the JHP. Then the hepatoprotective activity of peptides was evaluated through experiments in mice. The primary structure of the peptide with the strongest liver protective activity was Lys-Arg-Gln-Lys-Tyr-Asp (KRQKYD) and the peptide was derived from the myosin of Jinhua ham, which were both identified by LC-MS/MS. Furthermore, the mechanism of KRQKYD prevention against ALD was attributed to the fact that KRQKYD increases the abundance of Akkermansia muciniphila in the gut and decreases the abundance of Proteobacteria (especially Escherichia_Shigella). The LPS-mediated liver inflammatory cascade was reduced by protecting the intestinal barrier, increasing the tight connection of intestinal epithelial cells and reducing the level of LPS in the portal venous circulation. KRQKYD could inhibit the production of ROS by upregulating the expression of the NRF2/HO-1 antioxidant defense system and by reducing oxidative stress injury in liver cells. This study can provide a theoretical foundation for the application of JHP in the protection of liver from ALD.

Decompose quantitative susceptibility mapping (QSM) to sub-voxel diamagnetic and paramagnetic components based on gradient-echo MRI data

PURPOSE

A method named DECOMPOSE-QSM is developed to decompose bulk susceptibility measured with QSM into sub-voxel paramagnetic and diamagnetic components based on a three-pool complex signal model.

METHODS

Multi-echo gradient echo signal is modeled as a summation of three weighted exponentials corresponding to three types of susceptibility sources: reference susceptibility, diamagnetic and paramagnetic susceptibility relative to the reference. Paramagnetic component susceptibility (PCS) and diamagnetic component susceptibility (DCS) maps are constructed to represent the sub-voxel compartments by solving for linear and nonlinear parameters in the model.

RESULTS

Numerical forward simulation and phantom validation confirmed the ability of DECOMPOSE-QSM to separate the mixture of paramagnetic and diamagnetic components. The PCS obtained from temperature-variant brainstem imaging follows the Curie's Law, which further validated the model and the solver. Initial in vivo investigation of human brain images showed the ability to extract sub-voxel PCS and DCS sources that produce visually enhanced contrast between brain structures comparing to threshold QSM.

Hepatic Failure in COVID-19: Is Iron Overload the Dangerous Trigger?

Liver injury in COVID-19 patients has progressively emerged, even in those without a history of liver disease, yet the mechanism of liver pathogenicity is still controversial. COVID-19 is frequently associated with increased serum ferritin levels, and hyperferritinemia was shown to correlate with illness severity. The liver is the major site for iron storage, and conditions of iron overload have been established to have a pathogenic role in development of liver diseases. We presented here six patients who developed severe COVID-19, with biochemical evidence of liver failure. Three cases were survived patients, who underwent liver biopsy; the other three were deceased patients, who were autopsied. None of the patients suffered underlying liver pathologies. Histopathological and ultrastructural analyses were performed. The most striking finding we demonstrated in all patients was iron accumulation into hepatocytes, associated with degenerative changes. Abundant ferritin particles were found enclosed in siderosomes, and large aggregates of hemosiderin were found, often in close contact with damaged mitochondria. Iron-caused oxidative stress may be responsible for mitochondria metabolic dysfunction. In agreement with this, association between mitochondria and lipid droplets was also found. Overall, our data suggest that hepatic iron overload could be the pathogenic trigger of liver injury associated to COVID-19.

The iron chelating activity of Gundelia tournefortii in iron overloaded experimental rats

ETHNOPHARMACOLOGICAL RELEVANCE

Gundelia tournefortii is a member of the Asteraceae (Compositae) family which is widely consumed as edible plant in the Eastern Mediterranean. In folkloric medicine, it is used for the treatment of various diseases and conditions, including pain, liver diseases, kidney stones and inflammations.

AIM OF THE STUDY

Recently, many commoners use this plant as adjuvant therapy for treating symptoms associated with liver diseases and thalassemia. Thus, the present study was conducted to evaluate, biochemically, the iron chelating activity of G. tournefortii methanolic extract in iron overloaded rats.

MATERIALS AND METHODS

Fifty Wister male rats were divided into five groups: one group was a healthy control, while iron overload was induced in the other four groups by 100 mg/kg iron-dextran. Of these, one group was left untreated as a control, while the other three groups were treated with 50 mg/kg deferoxamine, 100 mg/kg and 200 mg/kg of G. tournefortii methanolic extract, respectively. The total flavonoid and phenolic contents of the methanolic extract were estimated. The biochemical assessment was performed by measuring blood levels of iron, ferritin, liver biomarkers (ALT, ALP and AST), cardiac biomarkers (CPK and LDH) and lipid profile.

RESULTS

Not only the blood levels of iron, ferritin, liver biomarkers and cardiac biomarkers were reduced significantly by G. tournefortii methanolic extract, but also the lipid profile was improved. This clearly supports the chelating activity of G. tournefortii and its hepatoprotective and cardioprotective effects in iron overloaded rats.

CONCLUSIONS

This highlights the value of medicinal plants as alternative therapies for iron overload conditions such as thalassemia.

Dietary Iron Overload Differentially Modulates Chemically-Induced Liver Injury in Rats

Hepatic iron overload is well known as an important risk factor for progression of liver diseases; however, it is unknown whether it can alter the susceptibility to drug-induced hepatotoxicity. Here we investigate the pathological roles of iron overload in two single-dose models of chemically-induced liver injury. Rats were fed a high-iron (Fe) or standard diet (Cont) for four weeks and were then administered with allyl alcohol (AA) or carbon tetrachloride (CCl₄). Twenty-four hours after administration mild mononuclear cell infiltration was seen in the periportal/portal area (Zone 1) in Cont-AA group, whereas extensive hepatocellular necrosis was seen in Fe-AA group. Centrilobular (Zone 3) hepatocellular necrosis was prominent in Cont-CCl₄ group, which was attenuated in Fe-CCl₄ group. Hepatic lipid peroxidation and hepatocellular DNA damage increased in Fe-AA group compared with Cont-AA group. Hepatic caspase-3 cleavage increased in Cont-CCl₄ group, which was suppressed in Fe-CCl₄ group. Our results showed that dietary iron overload exacerbates AA-induced Zone-1 liver injury via enhanced oxidative stress while it attenuates CCl₄-induced Zone-3 liver injury, partly via the suppression of apoptosis pathway. This study suggested that susceptibility to drugs or chemical compounds can be differentially altered in iron-overloaded livers.

Epigallocatechin Gallate Protects Mice against Methionine-Choline-Deficient-Diet-Induced Nonalcoholic Steatohepatitis by Improving Gut Microbiota To Attenuate Hepatic Injury and Regulate Metabolism

Epigallocatechin gallate (EGCG) has been regarded as a protective bioactive polyphenol in green tea against nonalcoholic steatohepatitis (NASH), but the mechanism remains poorly deciphered. Herein, we assessed the role and mechanism of EGCG on gut microbiota and the metabolism in NASH development. Forty-eight male C57BL/6J mice were fed with either a methionine-choline-sufficient diet or a methionine-choline-deficient (MCD) diet with or without EGCG administration for 4 weeks. Liver injury, inflammation, lipid accumulation, and iron overload were examined. 16S ribosomal RNA sequencing was used to detect the fecal microbiome. In our research, we observed that EGCG notably improved MCD-diet-derived gut microbiota dysbiosis, as proved by a distinctively clustered separation from that of the MCD group and by the decrease of the Oxalobacter, Oscillibacter, Coprococcus_1, and Desulfovibrio genera and enrichment of norank_f__Bacteroidales_S24_7_group, Alloprevotella, and Bacteroides. Spearman-correlation heatmap analysis indicated that Bacteroides and Alloprevotella induced by EGCG were strongly negatively correlated with lipid accumulation. Functional enzymes of the gut microbiome were predicted by PICRUSt based on the operation classification unit. The results revealed that 1468 enzymes were involved in various metabolic pathways, and 371 enzymes showed distinct changes between untreated and EGCG-treated mice. Long-chain-fatty-acid-CoA ligase ACSBG played a distinct role in fatty acid metabolism and ferroptosis and was significantly negatively correlated with Bacteroides. Altogether, the salutary effect of EGCG on NASH might be via shifting gut flora and certain enzymes from genera. Our study thus takes a step toward NASH prevention and therapy.

Current understanding of the metabolism of micronutrients in chronic alcoholic liver disease

Alcoholic liver disease (ALD) remains an important health problem worldwide. Perturbation of micronutrients has been broadly reported to be a common characteristic in patients with ALD, given the fact that micronutrients often act as composition or coenzymes of many biochemical enzymes responsible for the inflammatory response, oxidative stress, and cell proliferation. Mapping the metabolic pattern and the function of these micronutrients is a prerequisite before targeted intervention can be delivered in clinical practice. Recent years have registered a significant improvement in our understanding of the role of micronutrients on the pathogenesis and progression of ALD. However, how and to what extent these micronutrients are involved in the pathophysiology of ALD remains largely unknown. In the current study, we provide a review of recent studies that investigated the imbalance of micronutrients in patients with ALD with a focus on zinc, iron, copper, magnesium, selenium, vitamin D and vitamin E, and determine how disturbances in micronutrients relates to the pathophysiology of ALD. Overall, zinc, selenium, vitamin D, and vitamin E uniformly exhibited a deficiency, and iron demonstrated an elevated trend. While for copper, both an elevation and deficiency were observed from existing literature. More importantly, we also highlight several challenges in terms of low sample size, study design discrepancies, sample heterogeneity across studies, and the use of machine learning approaches.

TCDD promotes liver fibrosis through disordering systemic and hepatic iron homeostasis

2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin (TCDD) is a toxic environmental pollutant which can cause severe health problems, such as fibrosis. However, the toxic effects and related mechanism of TCDD on the liver remain largely unknown. In this study, we established a liver fibrosis mouse model upon exposure of TCDD, as evidenced by increased collagen I, tumor growth factor β1 (TGFβ1), α-smooth muscle actin (α-SMA), and Masson staining. Meanwhile, there was also a significant increase of inflammatory factors and TUNEL-positive hepatocytes in liver, indicating that liver inflammation and hepatic cell apoptosis occurred. In addition, increased serum and liver iron were concomitant with liver injury induced by TCDD. We further investigated the mechanism underlying TCDD-induced hepatocyte apoptosis through apoptosis polymerase chain reaction array, and found that a crucial apoptosis-related gene, cell death-inducing DFF45-like effector b (Cideb), was significantly increased in primary hepatocytes from TCDD-exposed mice, and accompanied by liver iron deposition in hepcidin knockout mice. Therefore, Cideb depletion could effectively attenuated TCDD or iron induced cell death related genes expression. In conclusion, our results showed that iron-induced Cideb expression played a critical role in promoting TCDD-induced hepatocyte apoptosis and liver fibrosis, which provide a novel mechanism for understanding TCDD-induced liver injury.

Prognostic Value of Serum Iron, Ferritin, and Transferrin in Chronic Alcoholic Liver Disease

Ethanol increases iron absorption. Therefore, increased amount of iron reaches the liver, and exerts pro-oxidant effects and stimulates ferritin synthesis and hepatic stellate cell activation, promoting fibrosis and inflammation. These mechanisms would theoretically support a role of ferritin as a marker of the transition to liver cirrhosis, and, consequently, as a prognostic factor, but there is controversy regarding its behavior in alcoholics. We analyzed among 238 severe alcoholics the prognostic value of iron, ferritin, transferrin, transferrin saturation index (TSI) and total iron binding capacity (TIBC), and the relationships of these variables with liver function, proinflammatory markers (C-reactive protein (CRP), interleukin (IL)-6, IL-8, and tumor necrosis factor α), and the presence of cirrhosis. Patients showed higher serum ferritin (Z = 2.50, p = 0.031) but lower transferrin (t(264) = 4.81, p < 0.001), TIBC (t(262) = 4.44, p < 0.001), and iron (Z = 3.19, p = 0.001) values compared with 32 age- and sex-matched controls. Ferritin was related to inflammatory cytokines such as IL-8 (ρ = 0.18, p = 0.012) and to IL-6 (ρ = 0.16, p = 0.016), but not to liver function. On the contrary, cirrhotics showed lower transferrin (t(234) = 4.77, p < 0.001) and TIBC (t(232) = 4.67, p < 0.001), but higher TSI (Z = 3.35, p < 0.001) than non-cirrhotics. Transferrin, TSI, and TIBC were related to liver function impairment (marked differences among the Child's groups regarding transferrin (KW (2) = 22.83, p < 0.001), TSI (KW (2) = 15.81, p < 0.001), and TIBC (KW (2) = 21.38, p < 0.001) but only weakly to inflammation (inverse relationships between IL-6 and total iron (ρ = - 0.16, p = 0.017), TIBC (ρ = - 0.20, p = 0.002), and transferrin (ρ = - 0.20, p = 0.003). In accordance, albumin, IL-6, alcohol quitting, and TSI, in this order, were independently related to mortality, but not ferritin or iron.

Differential effects of Fe2+ and Fe3+ on osteoblasts and the effects of 1,25(OH)2D3, deferiprone and extracellular calcium on osteoblast viability under iron-overloaded conditions

One of the potential contributing factors for iron overload-induced osteoporosis is the iron toxicity on bone forming cells, osteoblasts. In this study, the comparative effects of Fe³⁺ and Fe²⁺ on osteoblast differentiation and mineralization were studied in UMR-106 osteoblast cells by using ferric ammonium citrate and ferrous ammonium sulfate as Fe³⁺ and Fe²⁺ donors, respectively. Effects of 1,25 dihydroxyvitamin D₃ [1,25(OH)₂D₃] and iron chelator deferiprone on iron uptake ability of osteoblasts were examined, and the potential protective ability of 1,25(OH)₂D₃, deferiprone and extracellular calcium treatment in osteoblast cell survival under iron overload was also elucidated. The differential effects of Fe³⁺ and Fe²⁺ on reactive oxygen species (ROS) production in osteoblasts were also compared. Our results showed that both iron species suppressed alkaline phosphatase gene expression and mineralization with the stronger effects from Fe³⁺ than Fe²⁺. 1,25(OH)₂D₃ significantly increased the intracellular iron but minimally affected osteoblast cell survival under iron overload. Deferiprone markedly decreased intracellular iron in osteoblasts, but it could not recover iron-induced osteoblast cell death. Interestingly, extracellular calcium was able to rescue osteoblasts from iron-induced osteoblast cell death. Additionally, both iron species could induce ROS production and G0/G1 cell cycle arrest in osteoblasts with the stronger effects from Fe³⁺. In conclusions, Fe³⁺ and Fe²⁺ differentially compromised the osteoblast functions and viability, which can be alleviated by an increase in extracellular ionized calcium, but not 1,25(OH)₂D₃ or iron chelator deferiprone. This study has provided the invaluable information for therapeutic design targeting specific iron specie(s) in iron overload-induced osteoporosis. Moreover, an increase in extracellular calcium could be beneficial for this group of patients.

Mechanisms of liver fibrosis and its role in liver cancer

Hepatic fibrogenesis is a pathophysiological outcome of chronic liver injury hallmarked by excessive accumulation of extracellular matrix proteins. Fibrosis is a dynamic process that involves cross-talk between parenchymal cells (hepatocytes), hepatic stellate cells, sinusoidal endothelial cells and both resident and infiltrating immune cells. In this review, we focus on key cell-types that contribute to liver fibrosis, cytokines, and chemokines influencing this process and what it takes for fibrosis to regress. We discuss how mitochondria and metabolic changes in hepatic stellate cells modulate the fibrogenic process. We also briefly review how the presence of fibrosis affects development of hepatocellular carcinoma.

Evaluation of serum iron overload, AST:ALT ratio and log10ferritin:AST ratio among schizophrenia patients in the Kumasi Metropolis, Ghana: a case-control study

OBJECTIVE

The association between unbalanced iron indices and the conditions of schizophrenia are not well understood. Liver dysfunction which has been linked to iron metabolism might be a contributing factor. This case-control study evaluated serum iron indices and liver function in treatment-naïve schizophrenia patients and those already on treatment at the Psychiatric Department of the Komfo Anokye Teaching Hospital (KATH), Kumasi-Ghana.

RESULTS

The mean age of the respondents was 39.6 ± 0.8 years. Increased levels of serum iron, TS, AST, ALT and AST:ALT ratio and lower levels of UIBC, TIBC, Transferrin, and log Ferritin:AST ratio levels were observed among the treatment-naïve group compared to the control. The treatment-naïve and treatment groups showed significantly higher serum AST:ALT ratio, and lower log10ferrtin:AST ratio than the healthy controls. There was a significant correlation between log10ferritin and AST, and log10ferritin and GGT in both treatments (r = 0.343; p = 0.003, and r = 0.502; p = 0.001 respectively) and treatment-naïve groups (r = 0.348; p = 0.002, and r = 0.614; p < 0.001 respectively). Percentage transferrin saturation correlated significantly with GGT only, in the treatment-naïve group (r = 0.667; p < 0.001), and ALT and GGT in the treatment group (r = 0.252; p = 0.030 and r = 0.646; p = 0.014 respectively).

Iron chelation by deferasirox confers protection against concanavalin A-induced liver fibrosis: A mechanistic approach

Hepatic iron overload is one of the causative factors for chronic liver injury and fibrosis. The present study aimed to investigate the potential antifibrotic effect of the iron chelator; deferasirox (DFX) in experimentally-induced liver fibrosis in rats. Male Sprague-Dawley rats were administered concanavalin A (Con A) and/or DFX for 6 consecutive weeks. Con A injection induced significant hepatotoxicity as was evident by the elevated transaminases activity, and decreased albumin level. Also, it disturbed the iron homeostasis through increasing C/EBP homologous protein (CHOP), decreasing phosphorylated cAMP responsive element binding protein(P-CREB) and hepcidin levels leading to significant serum and hepatic iron overload. In addition, it induced an imbalance in the oxidative status of the liver via upregulating NADPH oxidase 4 (NOX4), together with a marked decrease in anti-oxidant enzymes' activities. As a consequence, upregulation of nuclear factor-kappa b (NF-κB) and the downstream inflammatory mediators was observed. Those events all together precipitated in initiation of liver fibrosis as confirmed by the elevation of alpha-smooth muscle actin (α-SMA) and liver collagen content. Co-treatment with DFX protected against experimentally-induced liver fibrosis in rats via its iron chelating, anti-oxidant, and anti-inflammatory properties. These findings imply that DFX can attenuate the progression of liver fibrosis.

[The role of iron overload in the progression of nonalcoholic steatohepatitis (NASH)]

Non-alcoholic steatohepatitis (NASH), one of the most common chronic liver diseases (CLD), is getting the most important cause of cirrhosis and hepatocellular carcinoma. Iron is an essential micronutrient for organisms. Once excess iron is accumulated in vital organs, dysfunctions of these organs can occur via the generation of reactive oxygen species. Hepatic iron overload is often seen in CLD patients. In NASH patients, iron accumulation in the liver is positively correlated with histological severity. Thus iron overload can contribute to progression of nonalcoholic fatty liver disease (NAFLD) to NASH. In a rat model of NASH, feeding of high-fat and high-iron diet increases hepatic inflammation with increased hepatic cytokine expression compared with feeding of high-fat diet only. In this model, iron is intensely accumulated in Kupffer cells/macrophages within the lesion, raising the possibility that iron-laden Kupffer cells/macrophages can play a key role in the enhancement of hepatic inflammation in NASH condition. On the other hand, in a rat model of liver cirrhosis, dietary iron overload clearly abrogates the development and progression of liver cirrhosis induced by repeated administration of thioacetamide (TAA). These findings suggest that iron overload can promote or suppress chronic liver diseases depending on the tissue microenvironment. Here we review and introduce the recent findings on the pathological roles of iron overload in the development and progression of NAFLD/NASH.

Iron overload reduces synthesis and elimination of bile acids in rat liver

Excessive iron accumulation in the liver, which accompanies certain genetic or metabolic diseases, impairs bile acids (BA) synthesis, but the influence of iron on the complex process of BA homeostasis is unknown. Thus, we evaluated the effect of iron overload (IO) on BA turnover in rats. Compared with control rats, IO (8 intraperitoneal doses of 100 mg/kg every other day) significantly decreased bile flow as a consequence of decreased biliary BA secretion. This decrease was associated with reduced expression of Cyp7a1, the rate limiting enzyme in the conversion of cholesterol to BA, and decreased expression of Bsep, the transporter responsible for BA efflux into bile. However, IO did not change net BA content in faeces in response to increased intestinal conversion of BA into hyodeoxycholic acid. In addition, IO increased plasma cholesterol concentrations, which corresponded with reduced Cyp7a1 expression and increased expression of Hmgcr, the rate-limiting enzyme in de novo cholesterol synthesis. In summary, this study describes the mechanisms impairing synthesis, biliary secretion and intestinal processing of BA during IO. Altered elimination pathways for BA and cholesterol may interfere with the pathophysiology of liver damage accompanying liver diseases with excessive iron deposition.

Iron mediated hematological, oxidative and histological alterations in freshwater fish Labeo rohita

Iron is an essential element for many physiological functions of several organisms but in excess it causes toxicity. High iron content in water bodies of mountainous states is considered as one of the major factor, responsible for low productivity in aquaculture systems. But, till date comprehensive reports on the adverse effect of iron overload in aquatic organisms, especially cultured fishes are scanty. Therefore, the present study was undertaken to investigate the adverse effects of iron overload in economically important aquaculture fish species Labeo rohita. Three sub-lethal test concentration of iron (ferrous) viz., 1/16th, 1/8th and 1/4th of LC₅₀ (post 96 h) i.e. 8.25, 16.51 and 33.01 mg L^-1, respectively, were used for in vivo exposure. Blood cells and tissue samples of the control & exposed specimens were sampled at intervals of 24, 48, 72 and 96 h to assess alterations in hematological, oxidative stress and histological parameters. Significant changes in erythrocyte and leukocyte counts, hemoglobin, lipid peroxidation, antioxidant enzyme activity (super oxide dismutase and catalase) and tissue iron accumulation were observed in the exposed fish. Significant increase in lipid peroxidation, coupled with significant reduction in free radicals scavengers like super oxide dismutase and catalase revealed a compromised anti-oxidative defense mechanism in the fishes exposed to iron overload. Histological examination of gills and liver showed severe tissue injury and histological alternations. Severity was found to increase in time and concentration dependent manner. Perl's staining revealed accumulation of excess iron in liver of the exposed fish. The observed patho-physiological changes in the present study provide the most comprehensive insight of iron overload stress in L. rohita.

Iron and liver fibrosis: Mechanistic and clinical aspects

Liver fibrosis is characterised by excessive deposition of extracellular matrix that interrupts normal liver functionality. It is a pathological stage in several untreated chronic liver diseases such as the iron overload syndrome hereditary haemochromatosis, viral hepatitis, alcoholic liver disease, non-alcoholic fatty liver disease, non-alcoholic steatohepatitis and diabetes. Interestingly, regardless of the aetiology, iron-loading is frequently observed in chronic liver diseases. Excess iron can feed the Fenton reaction to generate unquenchable amounts of free radicals that cause grave cellular and tissue damage and thereby contribute to fibrosis. Moreover, excess iron can induce fibrosis-promoting signals in the parenchymal and non-parenchymal cells, which accelerate disease progression and exacerbate liver pathology. Fibrosis regression is achievable following treatment, but if untreated or unsuccessful, it can progress to the irreversible cirrhotic stage leading to organ failure and hepatocellular carcinoma, where resection or transplantation remain the only curative options. Therefore, understanding the role of iron in liver fibrosis is extremely essential as it can help in formulating iron-related diagnostic, prognostic and treatment strategies. These can be implemented in isolation or in combination with the current approaches to prepone detection, and halt or decelerate fibrosis progression before it reaches the irreparable stage. Thus, this review narrates the role of iron in liver fibrosis. It examines the underlying mechanisms by which excess iron can facilitate fibrotic responses. It describes the role of iron in various clinical pathologies and lastly, highlights the significance and potential of iron-related proteins in the diagnosis and therapeutics of liver fibrosis.

High Carbohydrate High Fat Diet Induced Hepatic Steatosis and Dyslipidemia Were Ameliorated by Psidium guajava Leaf Powder Supplementation in Rats

Psidium guajava leaf is reported to contain many bioactive polyphenols which play an important role in the prevention and treatment of various diseases. Our investigation aimed to study the effect of Psidium guajava leaf powder supplementation on obesity and liver status by using experimental rats. To study the effects of guava leaf supplementation in high fat diet induced obesity, rats were randomly divided into four experimental groups (n=7), control (group I), control + guava leaf (group II), HCHF (group III), and HCHF + guava leaf (group IV). At the end of the experimental period (56 days), glucose intolerance, liver enzymes activities, antioxidant enzymes activities, and lipid and cholesterol profiles were evaluated. Our results revealed that guava leaf powder supplementation showed a significant reduction in fat deposition in obese rats. Moreover, liver enzyme functions were increased in high fat diet fed rats compared to the control rats significantly which were further ameliorated by guava leaf powder supplementation in high fat diet fed rats. High fat diet feeding also decreased the antioxidant enzyme functions and increased the lipid peroxidation products compared to the control rats. Guava leaf powder supplementation in high fat diet fed rats reduced the oxidative stress markers and reestablished antioxidant enzyme system in experimental animals. Guava leaf powder supplementation in high fat diet fed rats also showed a relative decrease in inflammatory cells infiltration and collagen deposition in the liver compared to the high fat diet fed rats. The present study suggests that the supplementation of guava leaf powder prevents obesity, improves glucose intolerance, and decreases inflammation and oxidative stress in liver of high carbohydrate high fat diet fed rats.

Dietary Iron Overload Abrogates Chemically-Induced Liver Cirrhosis in Rats

Chronic liver disease is an intractable disease, which can progress to cirrhosis and hepatocellular carcinoma. Hepatic iron overload is considered to be involved in the progression of chronic liver diseases; however, the mechanism remains to be elucidated. Here we investigate the role of dietary iron overload using chemically-induced liver cirrhosis model. Rats were fed a high-iron or standard diet and were injected intraperitoneally with thioacetamide (TAA) or saline twice a week for 20 weeks. Rats with TAA treatment (TAA group) had progressive liver cirrhosis characterized by persistent hepatocellular injury, mononuclear cell inflammation and bridging fibrosis; these lesions were markedly reduced in rats with iron feeding and TAA treatment (Fe-TAA group). Rats with iron feeding alone (Fe group) had no evidence of liver injury. Hepatic expression of cleaved caspase-3, but not phospho-RIP3, was decreased in Fe-TAA group compared with that in TAA group. The number of TUNEL-positive (terminal deoxynucleotidyl transferase dUTP nick end labeling) apoptotic hepatocytes was lower in the Fe-TAA group than in the TAA group. Hepatic xenobiotic metabolism and lipid peroxidation were shown to be less related to the abrogation of liver cirrhosis. Our results suggested that dietary hepatic iron overload abrogates chemically-induced liver cirrhosis in rats, which could partly involve decreased hepatocellular apoptosis.

Transient Elastography (TE) is a Useful Tool for Assessing the Response of Liver Iron Chelation in Sickle Cell Disease Patients

Sickle cell disease patients often need regular blood transfusions to improve both the quality of life and survival from the veno-occlusive complications of the disease. Deferasirox, a convenient long acting oral agent, has recently been introduced in clinical practice with promising efficacy.

This study aims to evaluate the association of liver stiffness and possible fibrosis with iron deposition and confirm the use of elastography as a validated test of responding to chelation with low cost and easy access.

15 patients with sickle cell disease and systemic or occasional transfusions were evaluated with MRI, transient elastography and biochemistry, for liver iron(LIC) and liver stiffness(LSM) before onset and one year after taking Deferasirox. All patients completed the study.

Our results showed improvement in hepatic iron and hepatic stiffness after chelation therapy; Furthermore ALT, AST, LDH and ferritin levels have improved after 12 months of therapy with deferasirox. During the study no serious adverse events were encountered indicating the safety of the drug.

Transient liver elastography findings correlate with serum ferritin and LIC in patients with sickle cell disease and it is a useful tool for assessing the response of liver iron chelation therapy.

Dietary Iron Supplementation Alters Hepatic Inflammation in a Rat Model of Nonalcoholic Steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is now the most common liver disease in the world. NAFLD can progress to nonalcoholic steatohepatitis (NASH), cirrhosis and eventually hepatocellular carcinoma. Acquired hepatic iron overload is seen in a number of patients with NAFLD; however, its significance in the pathology of NAFLD is still debated. Here, we investigated the role of dietary iron supplementation in experimental steatohepatitis in rats. Rats were fed a control, high-fat (HF), high-fat high-iron (HFHI) and high-iron (HI) diet for 30 weeks. Blood biochemical, histopathological and gut microbiota analyses were performed. Rats in HF and HFHI groups showed an ALT-dominant elevation of serum transaminases, hepatic steatosis, hepatic inflammation, and upregulation of proinflammatory cytokines. The number of large inflammatory foci, corresponding to lobular inflammation in NASH patients, was significantly higher in HFHI than in HF group; within the lesion, macrophages with intense iron staining were observed. Hepatic expression of TNFα was higher in HFHI than that in HF group. There was no significant change in hepatic oxidative stress, gut microbiota or serum endotoxin levels between HF and HFHI groups. These results suggested that dietary iron supplementation enhances experimental steatohepatitis induced by long-term high-fat diet feeding in rats. Iron-laden macrophages can play an important role in the enhancement of hepatic inflammation.

Deferoxamine alleviates liver fibrosis induced by CCl4 in rats

Several chronic liver diseases can lead to the occurrence of hepatic fibrosis through the accumulation of iron, which causes induction of oxidative stress and consequently activation of fibrogenesis. The present study was designed to investigate the potential antifibrotic and anti-oxidant effects of deferoxamine (DFO), a well-known iron chelator in an experimental rat model of liver injury using carbon tetrachloride (CCl4 ). First, the potential effective dose of DFO was screened against CCl4 -induced acute hepatotoxicity. Then, rats were co-treated with DFO (300 mg/kg, i.p.) for 6 weeks starting from the third week of CCl4 induction of chronic hepatotoxicity. Liver function was assessed in addition to histopathological examination. Furthermore, oxidative stress and fibrosis markers were assessed. It was found that treatment of animals with DFO significantly counteracted the changes in liver function; histopathological lesions and hepatic iron deposition that were induced by CCl4 . DFO also significantly counteracted the CCl4 -induced lipid peroxidation increase and reduction in antioxidant activities of superoxide dismutase and glutathione peroxidase enzymes. In addition, DFO ameliorated significantly liver fibrosis markers including hydroxyproline, collagen accumulation, and the expression of the hepatic stellate cells (HSCs) activation marker; alpha smooth muscle actin and transforming growth factor-beta (TGF-β). Together, these findings indicate that DFO possesses a potent antifibrotic effect due to its antioxidant properties that counteracted oxidative stress and lipid peroxidation and restored antioxidant enzymes activities as well as reducing HSCs activation and fibrogenesis.

Iron Enhances Hepatic Fibrogenesis and Activates Transforming Growth Factor-β Signaling in Murine Hepatic Stellate Cells

BACKGROUND

Although excess iron induces oxidative stress in the liver, it is unclear whether it directly activates the hepatic stellate cells (HSC).

MATERIALS AND METHODS

We evaluated the effects of excess iron on fibrogenesis and transforming growth factor beta (TGF-β) signaling in murine HSC. Cells were treated with holotransferrin (0.005-5g/L) for 24 hours, with or without the iron chelator deferoxamine (10µM). Gene expressions (α-SMA, Col1-α1, Serpine-1, TGF-β, Hif1-α, Tfrc and Slc40a1) were analyzed by quantitative real time-polymerase chain reaction, whereas TfR1, ferroportin, ferritin, vimentin, collagen, TGF-β RII and phospho-Smad2 proteins were evaluated by immunofluorescence, Western blot and enzyme-linked immunosorbent assay.

RESULTS

HSC expressed the iron-uptake protein transferrin receptor 1 (TfR1) and the iron-export protein ferroportin. Holotransferrin upregulated TfR1 expression by 1.8-fold (P < 0.03) and ferritin accumulation (iron storage) by 2-fold (P < 0.01), and activated HSC with 2-fold elevations (P < 0.03) in α-SMA messenger RNA and collagen secretion, and a 1.6-fold increase (P < 0.01) in vimentin protein. Moreover, holotransferrin activated the TGF-β pathway with TGF-β messenger RNA elevated 1.6-fold (P = 0.05), and protein levels of TGF-β RII and phospho-Smad2 increased by 1.8-fold (P < 0.01) and 1.6-fold (P < 0.01), respectively. In contrast, iron chelation decreased ferritin levels by 30% (P < 0.03), inhibited collagen secretion by 60% (P < 0.01), repressed fibrogenic genes α-SMA (0.2-fold; P < 0.05) and TGF-β (0.4-fold; P < 0.01) and reduced levels of TGF-β RII and phospho-Smad2 proteins.

CONCLUSIONS

HSC express iron-transport proteins. Holotransferrin (iron) activates HSC fibrogenesis and the TGF-β pathway, whereas iron depletion by chelation reverses this, suggesting that this could be a useful adjunct therapy for patients with fibrosis. Further studies in primary human HSC and animal models are necessary to confirm this.

Inositol hexa phosphoric acid (phytic acid), a nutraceuticals, attenuates iron-induced oxidative stress and alleviates liver injury in iron overloaded mice

Inositol hexa phosphoric acid (IP6) or Phytic acid, a natural antioxidant of some leguminous plants, known to act as a protective agent for seed storage in plants by suppressing iron catalyzed oxidative process. Following the same mechanism, we have tested the effect of IP6 on iron overloaded in vitro oxidative stress, and studied it's in vivo hepatoprotective ability in iron-dextran (injection)-induced iron overloaded liver injury in mice (intraperitoneal). Our results showed that IP6 had in vitro iron chelation (IC₅₀ 38.4μg/ml) activity, with the inhibition of iron-induced lipid peroxidation (IC₅₀ 552μg/ml), and deoxyribose sugar degrading hydroxyl radicals (IC₅₀ 448.6μg/ml). Oral administration of IP6 (0-200mg/kg) revealed significant decrease in biochemical markers such as serum iron, total iron binding, serum ferritin and serum enzymes. Histopathology of liver stained with hematoxylin-eosin and Prussian blue showed reduced hepatocellular necrosis, ballooning and inflammation, indicating the restoration of normal cellular integrity. Interestingly, the IP6 was found to down-regulate the mRNA expression of tumor necrosis factor (TNF)-α, Interleukin (IL)-1β, and IL-6 in iron overloaded liver tissues. Thus, we provide an insight that IP6, a natural food component, can serve as an iron chelator against iron overload diseases like Thalassemia, and also as a dietary hepatoprotective supplement.

Early Detection of Hepatocellular Carcinoma: How to Screen and Follow up Patients with Liver Cirrhosis According to the GERMAN S3 Guideline?

Hepatocellular carcinoma (HCC) is frequently detected in pre-existing liver cirrhosis, but can also develop without such pre-conditions. There is an increasing trend of HCC incidence worldwide. In patients with liver cirrhosis, HCC has become the leading cause of death. At diagnosis the tumor has very often reached an advanced stage and curative treatment options are missing. Thus, early diagnosis would help the patient and prevent increasing healthcare costs. In our review we will summarize the recommendations of the German S3 guideline for the early diagnosis of HCC and will discuss the current literature in this context. The reader will learn which diagnostic tools are available and in what order they can be usefully applied. Surveillance should be done with ultrasound by a skilled examiner, additional imaging at best with state-of-the-art dynamic magnetic resonance.

Alcoholic liver disease: mechanisms of injury and targeted treatment

Alcoholic liver disease (ALD) is a complex process that includes a wide spectrum of hepatic lesions, from steatosis to cirrhosis. Cell injury, inflammation, oxidative stress, regeneration and bacterial translocation are key drivers of alcohol-induced liver injury. Alcoholic hepatitis is the most severe form of all the alcohol-induced liver lesions. Animal models of ALD mainly involve mild liver damage (that is, steatosis and moderate inflammation), whereas severe alcoholic hepatitis in humans occurs in the setting of cirrhosis and is associated with severe liver failure. For this reason, translational studies using humans and human samples are crucial for the development of new therapeutic strategies. Although multiple attempts have been made to improve patient outcome, the treatment of alcoholic hepatitis is still based on abstinence from alcohol and brief exposure to corticosteroids. However, nearly 40% of patients with the most severe forms of alcoholic hepatitis will not benefit from treatment. We suggest that future clinical trials need to focus on end points other than mortality. This Review discusses the main pathways associated with the progression of liver disease, as well as potential therapeutic strategies targeting these pathways.

Combined histological and hematological assessment of iron-induced organ damage in a gerbil model of iron overload

BACKGROUND

Previous studies with gerbil models have suggested that excessive iron exposure causes cardiomyopathy and hepatic injury, but pathological analysis was not comprehensive, preventing a detailed understanding of how the metal induces this damage.

METHODS AND RESULTS

Gerbils received single intraperitoneal injections of iron dextran (200 mg/kg) or saline and were then analyzed comprehensively for hematological and histological signs of organ damage. These tests included hematology parameters and determination of liver iron concentration, malondialdehyde levels and glutathione peroxidase activity; examination of heart and liver tissue stained with hematoxylin and eosin, Prussian-blue and Masson stain; and electron microscopy analysis of heart and liver ultrastructure. Iron-overloaded animals showed significantly different hematology parameters and significantly higher liver iron concentrations than saline-injected animals, as well as significantly higher malondialdehyde levels and significantly lower glutathione peroxidase activity. Histology analyses showed cellular damage, iron deposits, and both myocardial and liver fibrosis, while electron microscopy of heart and liver sections showed abundant iron deposition lysosomes, and disordered and swollen mitochondria. All these pathological changes increased with exposure time.

CONCLUSIONS

This comprehensive assessment of iron overload in a gerbil model suggests that excessive iron deposition induces extensive cellular damage, particularly fibrosis in heart and liver. This damage may be the direct result of iron-mediated lipid peroxide damage and of iron deposition that cause compression of myocardial and liver cells, as well as vascular occlusion.

Diagnosis and management of hereditary hemochromatosis

Hereditary hemochromatosis is a rare genetic disorder that can have significant clinical consequences. Hemochromatosis is associated with iron overload, and can initially be recognized through laboratory testing for serum ferritin and transferrin saturation. Genetic testing for the HFE mutation can be performed in patients with elevated iron indices and a suspicion for hemochromatosis or liver disease. The main pathway resulting in iron overload is through altered hepcidin levels. Treatment of patients with the clinical phenotype of hereditary hemochromatosis is commonly through phlebotomy for removal of excess iron stores. This article highlights the current information and data regarding the diagnosis and management of hemochromatosis.

Catecholamine stress hormones regulate cellular iron homeostasis by a posttranscriptional mechanism mediated by iron regulatory protein: implication in energy homeostasis

Adequate availability of iron is important for cellular energy metabolism. Catecholamines such as epinephrine and norepinephrine promote energy expenditure to adapt to conditions that arose due to stress. To restore the energy balance, epinephrine/norepinephrine-exposed cells may face higher iron demand. So far, no direct role of epinephrine/norepinephrine in cellular iron homeostasis has been reported. Here we show that epinephrine/norepinephrine regulates iron homeostasis components such as transferrin receptor-1 and ferritin-H in hepatic and skeletal muscle cells by promoting the binding of iron regulatory proteins to iron-responsive elements present in the UTRs of transferrin receptor-1 and ferritin-H transcripts. Increased transferrin receptor-1, decreased ferritin-H, and increased iron-responsive element-iron regulatory protein interaction are also observed in liver and muscle tissues of epinephrine/norepinephrine-injected mice. We demonstrate the role of epinephrine/norepinephrine-induced generation of reactive oxygen species in converting cytosolic aconitase (ACO1) into iron regulatory protein-1 to bind iron-responsive elements present in UTRs of transferrin receptor-1 and ferritin-H. Our study further reveals that mitochondrial iron content and mitochondrial aconitase (ACO2) activity are elevated by epinephrine/norepinephrine that are blocked by the antioxidant N-acetyl cysteine and iron regulatory protein-1 siRNA, suggesting involvement of reactive oxygen species and iron regulatory protein-1 in this mechanism. This study reveals epinephrine and norepinephrine as novel regulators of cellular iron homeostasis.

Novel loci affecting iron homeostasis and their effects in individuals at risk for hemochromatosis

Variation in body iron is associated with or causes diseases, including anaemia and iron overload. Here, we analyse genetic association data on biochemical markers of iron status from 11 European-population studies, with replication in eight additional cohorts (total up to 48,972 subjects). We find 11 genome-wide-significant (P<5 × 10(-8)) loci, some including known iron-related genes (HFE, SLC40A1, TF, TFR2, TFRC, TMPRSS6) and others novel (ABO, ARNTL, FADS2, NAT2, TEX14). SNPs at ARNTL, TF, and TFR2 affect iron markers in HFE C282Y homozygotes at risk for hemochromatosis. There is substantial overlap between our iron loci and loci affecting erythrocyte and lipid phenotypes. These results will facilitate investigation of the roles of iron in disease.

[Diagnosis of and therapy for hepatocellular carcinoma]

The interdisciplinary guidelines at the S3 level on the diagnosis of and therapy for hepatocellular carcinoma (HCC) constitute an evidence- and consensus-based instrument that is aimed at improving the diagnosis of and therapy for HCC since these are very challenging tasks. The purpose of the guidelines is to offer the patient (with suspected or confirmed HCC) adequate, scientifically based and up-to-date procedures in diagnosis, therapy and rehabilitation. This holds not only for locally limited or focally advanced disease but also for the existence of recurrences or distant metastases. Besides making a contribution to an appropriate health-care service, the guidelines should also provide the foundation for an individually adapted, high-quality therapy. The explanatory background texts should also enable non-specialist but responsible colleagues to give sound advice to their patients concerning specialist procedures, side effects and results. In the medium and long-term this should reduce the morbidity and mortality of patients with HCC and improve their quality of life.

Multitargeted inhibition of hepatic fibrosis in chronic iron-overloaded mice by Salvia miltiorrhiza

ETHNOPHARMACOLOGICAL RELEVANCE

Salvia miltiorrhiza (SM, also known as Danshen) is a well-known Chinese medicinal herb, which has shown hepatoprotective effects with anti-fibrotic, anti-oxidative, anti-inflammatory and anti-apoptotic properties. To explore the effects and potential mechanism of SM against hepatic fibrosis induced by chronic iron overload in mice.

MATERIALS AND METHODS

Sixty male mice were randomized into five groups (n=12 in each group): control (saline), iron overload, iron overload with low-dose SM (3g/kg/day), iron overload with high-dose SM (6g/kg/day) and iron overload with deferoxamine (100mg/kg/day) groups. The iron overload model was established by intraperitoneal injection with iron dextran at 50mg/kg body weight/day, and the entire course lasted for 7 weeks. The major constituents of SM injection were quantified by high performance liquid chromatography. Changes of hepatic iron, hydroxyproline (Hyp), glutathione (GSH), superoxide dismutase (SOD) and malondialdehyde (MDA) were assayed by standard procedures. Protein expression levels of type I collagen, type III collagen, tumor necrosis factor-α (TNF-α) and interleukin-1α (IL-1α) were analyzed by immunohistochemistry, and mRNA levels of transforming growth factor-β (TGF-β), matrix metal proteinase-9 (MMP-9) and caspase-3 were detected by RT-PCR. Morphological changes were observed with Prussian blue, Masson's trichrome and hematoxylin-eosin staining.

RESULTS

Treatment of chronic iron-overloaded mice with SM dose-dependently ameliorated changes in hepatic morphology and coefficient, reduced iron deposition and Hyp content, suppressed overexpression of type I collagen and type III collagen, downregulated expression of TGF-β mRNA, and upregulated expression of MMP-9 mRNA in the liver. Moreover, SM treatment contributed to decreased MDA content, increased SOD activity and GSH content, while it reduced expression of TNF-α, IL-1α and caspase-3.

CONCLUSIONS

SM displayed anti-fibrotic activity in the liver induced by chronic iron overload, which may be attributed to multitargeted inhibition of iron deposition and collagen accumulation, as well as oxidative stress, inflammation and apoptosis.

Novel bioimaging techniques of metals by laser ablation inductively coupled plasma mass spectrometry for diagnosis of fibrotic and cirrhotic liver disorders

Background and Aims

Hereditary disorders associated with metal overload or unwanted toxic accumulation of heavy metals can lead to morbidity and mortality. Patients with hereditary hemochromatosis or Wilson disease for example may develop severe hepatic pathology including fibrosis, cirrhosis or hepatocellular carcinoma. While relevant disease genes are identified and genetic testing is applicable, liver biopsy in combination with metal detecting techniques such as energy-dispersive X-ray spectroscopy (EDX) is still applied for accurate diagnosis of metals. Vice versa, several metals are needed in trace amounts for carrying out vital functions and their deficiency due to rapid growth, pregnancy, excessive blood loss, and insufficient nutritional or digestive uptake results in organic and systemic shortcomings. Established in situ techniques, such as EDX-ray spectroscopy, are not sensitive enough to analyze trace metal distribution and the quantification of metal images is difficult.

Methods

In this study, we developed a quantitative biometal imaging technique of human liver tissue by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) in order to compare the distribution of selected metals in cryo-sections of healthy and fibrotic/cirrhotic livers.

Results

Most of the metals are homogeneous distributed within the normal tissue, while they are redirected within fibrotic livers resulting in significant metal deposits. Moreover, total iron and copper concentrations in diseased liver were found about 3-5 times higher than in normal liver samples.

Conclusions

Biometal imaging via LA-ICP-MS is a sensitive innovative diagnostic tool that will impact clinical practice in identification and evaluation of hepatic metal disorders and to detect subtle metal variations during ongoing hepatic fibrogenesis.

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.

A case-control histological study on the effects of phlebotomy in patients with chronic hepatitis C

OBJECTIVE

The aim of this study was to assess the actual effectiveness of long-term phlebotomy by comparing histological improvement (HI) in 69 Caucasian HCV-RNA-positive CHC patients undergoing phlebotomy or receiving an interferon-based therapy without virological response [nonresponders to interferon therapy(IBT-NR)].

METHODS

HI was defined by at least one point reduction of the staging score or, in the case of unchanged stage, by at least two points reduction of the grading score (Knodel's Activity Index) and was retrospectively evaluated by comparing two consecutive (56 ± 28 months apart) liver biopsies from 30 phlebotomized and 39 IBT-NR patients.

RESULTS

HI was observed in 15 of 30 (50%) patients treated with phlebotomy and in six of 39 (15%) IBT-NR subjects (P=0.002). Furthermore, AST, ALT, and GGT serum levels were significantly reduced only in phlebotomized patients (P ≤ 0.003) at the time of the second biopsy. Univariate and multivariate analysis showed that histological grading score before therapy (P=0.001) and phlebotomy (P=0.002) were independently predictors of HI.

CONCLUSION

HI induced by long-term phlebotomy effectively exceeds that spontaneously occurring in patients IBT-NR confirming the efficacy of iron depletion in attenuating CHC progression when other therapies have failed.

Non-alcoholic fatty liver disease: is iron relevant?

Non-alcoholic fatty liver disease (NAFLD) is a common and ubiquitous disorder (Bedogni et al. in Hepatology 42:44-52, 2005; Bellentani et al. in Ann Intern Med 132:112-117, 2000) which in a proportion of subjects leads to non-alcoholic steatohepatitis (NASH), advanced liver disease and hepatocellular carcinoma. Although the factors responsible for progression of disease are still uncertain, there is evidence that insulin resistance (IR) is a key operative mechanism (Angulo et al. in Hepatology 30:1356-1362, 1999) and that two stages are involved. The first is the accumulation of triglycerides in hepatocytes followed by a "second hit" which promotes cellular oxidative stress. Several factors may be responsible for the induction of oxidative stress but hepatic iron has been implicated in various studies. The topic is controversial, however, with early studies showing an association between hepatic iron (with or without hemochromatosis gene mutations) and the progression to hepatic fibrosis. Subsequent studies, however, could not confirm an association between the presence of hepatic iron and any of the histological determinants of NAFLD or NASH. Recent studies have reactivated interest in this subject firstly, with the demonstration that hepatic iron loading increases liver cholesterol synthesis with increased lipid deposition in the liver increasing the cellular lipid burden and secondly, a large clinical study has concluded that hepatocellular iron deposition is associated with an increased risk of hepatic fibrosis, thus, strongly supporting the original observation made over a decade ago. An improvement in insulin sensitivity has been demonstrated following phlebotomy therapy but a suitably powered controlled clinical trial is required before this treatment can be implemented.