Iron-enriched diet contributes to early onset of osteoporotic phenotype in a mouse model of hereditary hemochromatosis.

Osteoporosis is associated with chronic iron overload secondary to hereditary hemochromatosis (HH), but the causative mechanisms are incompletely understood. The main objective of this study was to investigate the role of dietary iron on osteoporosis, using as biological model the Hfe-KO mice, which have a systemic iron overload. We showed that these mice show an increased susceptibility for developing a bone loss phenotype compared to WT mice, which can be exacerbated by an iron rich diet. The dietary iron overload caused an increase in inflammation and iron incorporation within the trabecular bone in both WT and Hfe-KO mice. However, the osteoporotic phenotype was only evident in Hfe-KO mice fed the iron-enriched diet. This appeared to result from an imbalance between bone formation and bone resorption driven by iron toxicity associated to Hfe-KO and confirmed by a decrease in bone microarchitecture parameters (identified by micro-CT) and osteoblast number. These findings were supported by the observed downregulation of bone metabolism markers and upregulation of ferritin heavy polypeptide 1 (Fth1) and transferrin receptor-1 (Tfrc), which are associated with iron toxicity and bone loss phenotype. In WT mice the iron rich diet was not enough to promote a bone loss phenotype, essentially due to the concomitant depression of bone resorption observed in those animals. In conclusion the dietary challenge influences the development of osteoporosis in the HH mice model thus suggesting that the iron content in the diet may influence the osteoporotic phenotype in systemic iron overload conditions.

Molecular mechanisms related to the hepatoprotective effects of antioxidant-rich extra virgin olive oil supplementation in rats subjected to short-term iron administration.

Enhanced iron levels in liver are associated with oxidative stress development and damage with increased fat accumulation. The aim of this work was to assess the hypothesis that antioxidant-rich extra virgin olive oil (AR-EVOO) counteracts iron-rich diet (IRD)-induced oxidative stress hindering hepatic steatosis. Male Wistar rats were fed and IRD (200 mg iron/kg diet) versus a control diet (CD; 50 mg iron/kg diet) with alternate AR-EVOO supplementation (100 mg/day) for 21 days. IRD induced liver steatosis and oxidative stress (higher levels of protein oxidation and lipid peroxidation with glutathione depletion), mitochondrial dysfunction (decreased citrate synthase and complex I and II activities) and loss of polyunsaturated fatty acids (PUFAs), with a drastic enhancement in the sterol regulatory element-binding protein-1c (SREBP-1c)/peroxisome proliferator-activated receptor-α (PPAR-α) ratio upregulating the expression of lipogenic enzymes (acetyl-CoA carboxylase, fatty acid (FA) synthase and stearoyl desaturase 2) and downregulating those involved in FA oxidation (carnitine palmitoyl transferase and acyl-CoA oxidase) over values in the CD group. IRD also upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) and its target genes. AR-EVOO supplementation alone did not modify the studied parameters, however, IRD combined with AR-EVOO administration returned IRD-induced changes to baseline levels of the CD group. It is concluded that IRD-induced non-alcoholic fatty liver disease (NAFLD) is prevented by AR-EVOO supplementation, which might be related to the protective effects of its components such as hydroxytyrosol, oleic acid, tocopherols and/or PUFAs, thus representing a suitable anti-steatotic strategy to avoid progression into more severe stages of the disease, underlying NAFLD associated with iron overloading pathologies or obesity.

Copper supplementation reverses dietary iron overload-induced pathologies in mice.

Dietary iron overload in rodents impairs growth and causes cardiac hypertrophy, serum and tissue copper depletion, depression of serum ceruloplasmin (Cp) activity and anemia. Notably, increasing dietary copper content to ~25-fold above requirements prevents the development of these physiological perturbations. Whether copper supplementation can reverse these high-iron-related abnormalities has, however, not been established. The current investigation was thus undertaken to test the hypothesis that supplemental copper will mitigate negative outcomes associated with dietary iron loading. Weanling mice were thus fed AIN-93G-based diets with high (>100-fold in excess) or adequate (~80 ppm) iron content. To establish the optimal experimental conditions, we first defined the time course of iron loading, and assessed the impact of supplemental copper (provided in drinking water) on the development of high-iron-related pathologies. Copper supplementation (20 mg/L) for the last 3 weeks of a 7-week high-iron feeding period reversed the anemia, normalized serum copper levels and Cp activity, and restored tissue copper concentrations. Growth rates, cardiac copper concentrations and heart size, however, were only partially normalized by copper supplementation. Furthermore, high dietary iron intake reduced intestinal 64Cu absorption (~60%) from a transport solution provided to mice by oral, intragastric gavage. Copper supplementation of iron-loaded mice enhanced intestinal 64Cu transport, thus allowing sufficient assimilation of dietary copper to correct many of the noted high-iron-related physiological perturbations. We therefore conclude that high- iron intake increases the requirement for dietary copper (to overcome the inhibition of intestinal copper absorption).

Dietary supplementation of Spirulina ameliorates iron-induced oxidative stress in Indian knife fish Notopterus Notopterus.

Iron though an essential cofactor for many proteins including haemoglobin and cytochromes, when in excess (>1 ppm in water and 100 ppm in fish tissue) elicits toxicity via Fenton reaction inducing oxidative stress. The present study aimed to evaluate the efficacy of dietary Spirulina (Arthrospira platensis) supplementation on waterborne-iron induced oxidative stress in the tissues of Notopterus notopterus. Juvenile fishes were divided randomly into 4 groups, namely, Group-I: control fed with commercial diet only, Group-II, III and IV treated with 0.75 ppm FeCl3 where Group-II fed with commercial diet only, Group-III with 10% (w/w) Spirulina supplemented commercial diet and Group-IV with 100% (w/w) Spirulina diet only; for 7 and 28 days (n = 6 per group). Tissue oxidative stress biomarkers like lipid peroxidation (LPx), protein carbonylation (PC) and protein thionylation (protein and nonprotein-SH content); antioxidant defence (superoxide dismutase: SOD; catalase; CAT; glutathione peroxidase/reductase: GPx/GR; glutathione s-transferase: GST; metalothionine: MT and reduced glutathione: GSH) and iron accumulation in the gill, liver and muscles tissue were analysed. The augmented oxidative predominance in the tissues with respect to LPx and PC along with decline in antioxidant defence (SOD, CAT, GPx, GR, GST, MT, PSH, NPSH and GSH) by iron was neutralized by Spirulina supplementation in the diet in a dose and duration dependent manner where 100% Spirulina diet for 28 days completely ameliorated iron-induced oxidative stress in fish tissues. Thus, Spirulina can be used as a dietary supplement for fishes cultured in water bodies with iron overload.

Effects of green tea on iron accumulation and oxidative stress in livers of iron-challenged thalassemic mice.

Liver is affected by secondary iron overload in transfusions dependent b-thalassemia patients. The redox iron can generate reactive oxidants that damage biomolecules, leading to liver fibrosis and cirrhosis. Iron chelators are used to treat thalassemias to achieve negative iron balance and relieve oxidant-induced organ dysfunctions. Green tea (GT) (Camellia sinensis) catechins exhibit anti-oxidation, the inhibition of carcinogenesis, the detoxification of CYP2E1-catalyzed HepG2 cells and iron chelation. The purpose of this study was to investigate the effectiveness of GT in iron-challenged thalassemic mice. Heterozygous BKO type-thalassemia (BKO) mice (C57BL/6) experienced induced iron overload by being fed a ferrocene-supplemented diet (Fe diet) for 8 weeks, and by orally being given GT extract (300 mg/kg) and deferiprone (DFP) (50 mg/kg) for a further 8 weeks. Liver iron content (LIC) was analyzed by TPTZ colorimetric and Perl's staining techniques. Concentrations of liver reduced glutathione (GSH), collagen and malondialdehyde (MDA) were also measured. Dosages of the GT extract and DFP lowered LIC in the Fe diet-fed BKO mice effectively. The extract did not change any concentrations of liver glutathione, collagen and MDA in the BKO mice. Histochemical examination showed leukocyte infiltration in the near by hepatic portal vein and high iron accumulation in the livers of the iron-loaded BKO mice, however GT treatment lowered the elevated iron deposition. In conclusion, green tea inhibits or delays the deposition of hepatic iron in regularly iron-loaded thalassemic mice effectively. This will prevent the iron-induced generation of free radicals via Haber-Weiss and Fenton reactions, and consequently liver damage and fibrosis. Combined chelation with green tea would be investigated in beta-thalassemia patients with iron overload.

Effects of dietary iron reduction versus phlebotomy in patients with chronic hepatitis C: results from a randomized, controlled trial on 40 Japanese patients.

BACKGROUND AND AIM: Iron may play an important role in the pathogenesis of hepatitis C. We conducted this randomized, controlled trial comparing phlebotomy with dietary iron reduction. METHODS: Forty patients with chronic hepatitis C showing serum ferritin levels of over 150 ng/ml were randomized to either group A (low-iron diet for six months) or group B (phlebotomy biweekly). Phlebotomy was continued until serum ferritin had reached 20 ng/ml or less. RESULTS: At enrollment the clinical characteristics of patients in the two groups were similar. Serum ALT levels were significantly reduced in both groups, but the percent change in alanine aminotransferase (ALT) was larger in group B (median, -47.1 [range, -69.1 to -16.7] %) than in group A (-24.2 [-72.6 to 15.9] %, p<0.001). In group A subjects, no correlation was detected between percent change in ALT and clinical parameters. In group B subjects, the baseline ALT activity was significantly correlated with percent change in ALT (p<0.05), but iron-related parameters were not correlated. CONCLUSION: The efficacy of phlebotomy is superior to that of dietary iron reduction in chronic hepatitis C. Serum levels of transaminase activities were a better indicator for phlebotomy than conventional indices of iron overload.

Recurrence of iron deposition in the cardiac allograft in a patient with non-HFE hemochromatosis.

We report the case of a 36-year-old woman with a diagnosis of idiopathic dilated cardiomyopathy who underwent cardiac transplantation. The results of her initial iron studies were normal, but hemochromatosis was suspected after microscopy of the explanted heart revealed iron deposition. By 6 months post-transplantation, iron deposition was detected in her surveillance endomyocardial biopsy specimens and studies then confirmed the existence of non-HFE hemochromatosis. The patient has been stable on treatment with regular phlebotomies and a low vitamin C diet.

Beneficial influence of an indigenous low-iron diet on serum indicators of iron status in patients with chronic liver disease.

The main Fe storage organ in the body is the liver. In patients with chronic liver disease, secondary Fe overload is common. Phlebotomy, often used in the West to reduce Fe overload to improve the efficacy of interferon therapy, is not socially acceptable in India. We assessed the efficacy of a low-Fe diet in reducing serum Fe levels. Nineteen patients with hepatitis B- and C-related chronic liver disease, ten with normal (< 25 mumol/l) baseline serum Fe levels (group A) and nine with high (> 25 mumol/l) serum Fe levels (group B) were included. All the subjects were advised to eat a low-Fe diet. The daily Fe intake was reduced approximately 50% by consumption of the rice-based diet. Haemoglobin, serum Fe, transferrin saturation index (TSI), ferritin and alanine transaminase (EC 2.6.1.2) levels were studied at 1 and 4 months. Dietary Fe intake and body weight were closely monitored. All patients complied with the dietary regimen and at 4 months significant (P < 0.001) reductions from baseline were seen in serum Fe (20 (SD 3) v. 12 (SD 4) mumol/l group A; 30 (SD 3) v. 19 (SD 7) mumol/l group B) and TSI (38 (SD 8) v. 23 (SD 9)% group A; 53 (SD 15) v. 34 (SD 13)%, group B) in both the groups, albeit earlier in group B subjects. Serum ferritin levels, however, reduced only in group A (112 (SD 62) v. 43 (SD 25) ng/ml, P < 0.05) and not in group B. Non-significant reductions in haemoglobin levels were seen in both groups. Alanine transaminase levels reduced significantly (P < 0.05) in both the groups (95 (SD 49) v. 44 (SD 25) IU/l, group A; 82 (SD 16) v. 51 (SD 14) IU/l group B). Thus, a low-Fe diet results in significant reductions in serum Fe and TSI levels, irrespective of baseline Fe levels. This diet should be evaluated to improve the efficacy of interferon therapy in patients with hepatitis B- and C-related chronic liver disease.