In vivo evaluation of heme and non-heme iron content and neuronal density in human basal ganglia

Anemia is a condition of haemoglobin level that is below normal. One of the major causes is lacking of iron consumption, which is important in haemoposis process. Compared to men, women have less total iron in the body, and it raises the risk of anemia. The main purpose of this research was the fortification of iron in beverage. This research used soybean and mungbean as source of iron, which known as non-heme iron. To improve the absorption, ascorbic acid was needed as an enhancer, using guava and was produced into guava jelly drink. Method for extraction process is by maseration with 30% etanol as solution. The value of iron extract assessed by AAS at 248,3 nm. The formula of fortification was 20% of RDA of iron for woman, which was 18 mg per day. Chosen product was evaluated by sensory test. The nutrition value of product assessed including iron content, ascorbic acid, and proximate composition. The iron content of soybean was 113,86 ppm and 58,76 for mungbean. The nutrition of guava jelly drink with addition of fortificant were 87,47% water, 0,35% ash, 0,2% fat, 0,31% protein, 11,67% carbohydrate, 130,48 ppm iron, and 90,79 mg ascorbic acid. Keywords: iron deficiency anemia, soy bean, mungbean, jelly drink, and guava

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In vivo growth of Staphylococcus lugdunensis is facilitated by the concerted function of heme and non-heme iron acquisition mechanisms

10.1101/2022.01.12.476141 ◽

2022 ◽

Author(s):

Ronald S Flannagan ◽

Jeremy R Brozyna ◽

Brijesh Kumar ◽

Lea A Adolf ◽

Jeffrey J Power ◽

...

Keyword(s):

Iron Acquisition ◽

Stress Hormones ◽

Systemic Infection ◽

Culture Conditions ◽

Heme Iron ◽

Mammalian Host ◽

Staphylococcus Lugdunensis ◽

Non Heme Iron ◽

Gene Acquisition

Acquisition of iron underpins the ability of pathogens to cause disease and Staphylococcus lugdunensis has increasingly been recognized as a pathogen that can cause serious infection. In this study, we sought to address the knowledge gap that exists regarding the iron acquisition mechanisms employed by S. lugdunensis, especially during infection of the mammalian host. Here we show that S. lugdunensis utilizes diverse genome encoded iron acquisition mechanisms to satisfy its need for this nutrient. Indeed, S. lugdunensis can usurp hydroxamate siderophores, and staphyloferrin A and B from S. aureus, using the fhuC ATPase-encoding gene. Acquisition of catechol siderophores and catecholamine stress hormones necessitates the presence of the sst-1 transporter-encoding locus, but not the sst-2 locus. Iron-dependent growth in acidic culture conditions necessitates the feoAB locus. Heme iron is acquired via expression of the iron-regulated surface determinant (isd) locus. During systemic infection of mice we demonstrate that while S. lugdunensis does not cause overt illness, it does colonize and proliferate to high numbers in the kidneys. By combining mutations in the various iron acquisition loci, we further demonstrate that only a strain mutated for all of isd, fhuC, sst-1, and feo, versus combination mutants carrying wild type copies of any one of those loci, was attenuated in its ability to proliferate to high numbers in kidneys. Taken together our data reveal that S. lugdunensis requires a repertoire of both heme and non-heme iron acquisition mechanisms to proliferate during systemic infection of mammals

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Abstract 12425: Sirt2 Mediated-Deacetylation Regulates Cellular Iron Homeostasis

Circulation ◽

10.1161/circ.130.suppl_2.12425 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Xiaoyan Yang ◽

Athanassios Vassilopoulos ◽

Seong-Hoon Park ◽

David Gius ◽

Hossein Ardehali

Keyword(s):

Iron Content ◽

Iron Homeostasis ◽

Underlying Mechanism ◽

Heme Iron ◽

Iron Storage ◽

Cellular Iron ◽

Non Heme Iron ◽

Ferroportin 1 ◽

Cellular Iron Homeostasis ◽

Iron Export

Background: Sirtuins (SIRTs) are NAD+-dependent deacetylases and critical regulators of energy metabolism and response to oxidative stress in the heart. Iron is essential for these processes but is toxic when present in excess. Thus, SIRTs may regulate iron levels to ensure adequate supply of this element for their biological functions. SIRT2 is among the least characterized SIRTs and is mainly present in the cytoplasm. We hypothesized that SIRT2 might be required for cellular iron homeostasis. Methods and Results: Iron content was significantly lower in SIRT2-/- mouse embryonic fibroblasts (MEFs) compared to SIRT2+/+ MEFs (non-heme iron: 0.073 vs. 0.060 nmol/μg protein, p=0.02). Gene expression of ferroportin-1 (FPN1), the major cellular iron exporter, was significantly increased in SIRT2-/- MEFs. Similarly, silencing SIRT2 in HepG2 cells decreased cellular iron levels and increased FPN1 expression, indicating that enhanced FPN1 in SIRT2 knockout or knockdown condition increases iron export and reduces cellular iron. To investigate the underlying mechanism, we focused our studies on nuclear factor (erythroid-derived 2)-like 2 (Nrf2), a known regulator of FPN1. Our results demonstrated that Nrf2 is upregulated and translocates into the nucleus in SIRT2-/- MEFs and knocking down Nrf2 in SIRT2-/- MEFs reverses iron deficiency and FPN1 expression. Furthermore, Nrf2 is acetylated by P300/CBP and can be deacetylated by SIRT2. Finally, to confirm the role of SIRT2 in iron regulation, cellular heme and non-heme iron in the heart (major iron-consuming organ) and liver (major iron-storage organ) were measured in wild type (WT) and SIRT2-/- mice. Heme and non-heme iron content were significantly decreased in SIRT2-/- mouse livers compared to WT livers (heme: 2.25 vs. 1.65 nmol/mg protein, p=0.002; non-heme iron: 0.073 vs. 0.064 nmol/μg protein, p=0.03). Furthermore, heme levels were also significant decreased in the heart, while non-heme iron was not significantly altered. Conclusions: Our results suggest that SIRT2 regulates cellular iron homeostasis by deacetylating NRF2 and altering iron export through FPN1.

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Abstract 92: Sirtuin 2 mediated-deacetylation regulates cellular iron homeostasis

Circulation Research ◽

10.1161/res.115.suppl_1.92 ◽

2014 ◽

Vol 115 (suppl_1) ◽

Author(s):

Xiaoyan Yang ◽

Athanassios Vassilopoulos ◽

Seong-Hoon Park ◽

David Gius ◽

Hossein Ardehali

Keyword(s):

Iron Content ◽

Hepg2 Cells ◽

Iron Homeostasis ◽

Underlying Mechanism ◽

Heme Iron ◽

Iron Storage ◽

Cellular Iron ◽

Non Heme Iron ◽

Cellular Iron Homeostasis ◽

Iron Export

Background: Sirtuins (SIRTs) are NAD+-dependent deacetylases, which regulate energy metabolism and response to oxidative stress in the heart. Iron is essential for these processes but is toxic when present in excess. However, whether SIRTs are involved in maintaining cellular iron homeostasis is not known. SIRT2 is among the least characterized SIRTs and is mainly present in the cytoplasm. We hypothesized that SIRT2 is required for cellular iron homeostasis. Methods and Results: Iron content was significantly lower in SIRT2-/- mouse embryonic fibroblasts (MEFs) compared to SIRT2+/+ MEFs (non-heme iron: 0.073 vs. 0.060 nmol/μg protein, p=0.02), andlevels of ferroportin-1 (FPN1), the major cellular iron exporter, was significantly increased in SIRT2-/- MEFs. Similarly, silencing SIRT2 in HepG2 cells decreased cellular iron levels and increased FPN1 expression, indicating that enhanced FPN1 with SIRT2 downregulation drove iron export and caused a reduction in cellular iron levels. Furthermore, iron export assays showed that iron export was increased in HepG2 cells with SIRT2 knockdown. To investigate the underlying mechanism, we focused our studies on nuclear factor (erythroid-derived 2)-like 2 (Nrf2), a known regulator of FPN1. Our results demonstrated that Nrf2 is upregulated and translocates into the nucleus in SIRT2-/- MEFs and knocking down Nrf2 in SIRT2-/- MEFs reverses iron deficiency. Furthermore, Nrf2 is acetylated by P300/CBP and can be deacetylated by SIRT2. Finally, to confirm the role of SIRT2 in iron regulation, cellular heme and non-heme iron in the heart (major iron-consuming organ) and liver (major iron-storage organ) were measured in wild type (WT) and SIRT2-/- mice. Heme and non-heme iron content were significantly decreased in SIRT2-/- mouse livers compared to WT livers (heme: 2.25 vs. 1.65 nmol/mg protein, p=0.002; non-heme iron: 0.073 vs. 0.064 nmol/μg protein, p=0.03). Furthermore, heme levels were also significant decreased in the heart, while non-heme iron was not significantly altered. Conclusions: Our results suggest that SIRT2 regulates cellular iron homeostasis by deacetylating NRF2 and altering iron export through FPN1.

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Tmprss6 Is a Genetic Modifier of the Hfe-Hemochromatosis Phenotype in Mice.

Blood ◽

10.1182/blood.v114.22.625.625 ◽

2009 ◽

Vol 114 (22) ◽

pp. 625-625

Author(s):

Karin E. Finberg ◽

Rebecca Whittlesey ◽

Mark D. Fleming ◽

Nancy C. Andrews

Keyword(s):

Iron Deficiency ◽

Iron Content ◽

Serum Iron ◽

Iron Concentration ◽

Transferrin Saturation ◽

Heme Iron ◽

Deficiency Anemia ◽

Wild Type ◽

Non Heme Iron ◽

Serum Iron Concentration

Abstract Abstract 625 HFE-associated hereditary hemochromatosis is an autosomal recessive disorder characterized by inappropriately elevated absorption of dietary iron by the gastrointestinal mucosa, resulting in excessive storage of iron in multiple organs. A significant proportion of individuals who are homozygous for HFE mutations fail to develop clinical symptoms, suggesting that environmental and/or genetic factors may influence the penetrance of this disorder. In vitro and animal studies have revealed that HFE promotes the expression of hepcidin, a circulating hormone produced by the liver that acts to inhibit iron absorption by the duodenum. In contrast, TMPRSS6, a transmembrane serine protease produced by the liver, acts to inhibit hepcidin expression; both humans and mice harboring TMPRSS6 mutations display impaired intestinal iron absorption, resulting in a phenotype of iron-refractory iron deficiency anemia (IRIDA). Here we asked if heterozygous or homozygous loss of Tmprss6 function could modify the iron overload phenotype of Hfe null (Hfe-/-) mice, a mouse model of human HFE-hemochromatosis. To test this, we bred Hfe-/- mice to Tmprss6-/- mice; the latter harbor a targeted disruption of the Tmprss6 serine protease domain and exhibit an IRIDA phenotype. We generated Hfe-/-Tmprss6+/+, Hfe-/-Tmprss6+/-, and Hfe-/-Tmprss6-/- female mice (6-10 mice per genotype), in which parameters of systemic iron homeostasis were compared at eight weeks of age by Student's t test. Consistent with previous study of Hfe-/- mice, Hfe-/- mice harboring two wild type Tmprss6 alleles (Hfe-/-Tmprss6+/+ mice) showed serum iron concentration, transferrin saturation, and hepatic non-heme iron content that were significantly elevated compared to wild type mice of similar genetic background. Heterozygosity for Tmprss6 mutation, however, markedly reduced the severity of the hemochromatosis phenotype of Hfe-/- mice. Compared to Hfe-/- mice with two wild type Tmprss6 alleles, Hfe-/- mice that were heterozygous for Tmprss6 mutation (Hfe-/-Tmprss6+/- mice) showed significant reductions in serum iron concentration (p<0.01), transferrin saturation (p<0.005), and non-heme iron content of liver (p<10-4). Furthermore, homozygosity for Tmprss6 mutation completely ameliorated the iron overload phenotype of Hfe-/- mice and in fact led to systemic iron deficiency. Compared to both Hfe-/-Tmprss6+/+ and Hfe-/-Tmprss6+/- mice, Hfe-/-Tmprss6-/- mice showed markedly reduced serum iron concentration (p<10-7), transferrin saturation (p<10-10), and non-heme iron content of liver (p<10-4). Hfe-/-Tmprss6-/- mice also displayed iron deficiency anemia and appeared phenotypically similar to previously characterized Tmprss6-/- mice harboring two wild type copies of Hfe. In summary, these results demonstrate that Tmprss6 is a genetic modifier of the Hfe-hemochromatosis phenotype in mice. These findings suggest that natural genetic variation in the human ortholog TMPRSS6 might modify the clinical penetrance of HFE-hemochromatosis and raise the possibility that pharmacological inhibition of TMPRSS6 activity might prove an effective therapy in this disorder. Disclosures: No relevant conflicts of interest to declare.

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Expression of the DMT1 (NRAMP2/DCT1) iron transporter in mice with genetic iron overload disorders

Blood ◽

10.1182/blood.v97.4.1138 ◽

2001 ◽

Vol 97 (4) ◽

pp. 1138-1140 ◽

Cited By ~ 67

Author(s):

François Canonne-Hergaux ◽

Joanne E. Levy ◽

Mark D. Fleming ◽

Lynne K. Montross ◽

Nancy C. Andrews ◽

...

Keyword(s):

Iron Deficiency ◽

Iron Overload ◽

Mouse Models ◽

Brush Border ◽

Knockout Mice ◽

Heme Iron ◽

Iron Loading ◽

Non Heme Iron ◽

Iron Transporter

Abstract Iron overload is highly prevalent, but its molecular pathogenesis is poorly understood. Recently, DMT1 was shown to be a major apical iron transporter in absorptive cells of the duodenum. In vivo, it is the only transporter known to be important for the uptake of dietary non-heme iron from the gut lumen. The expression and subcellular localization of DMT1 protein in 3 mouse models of iron overload were examined: hypotransferrinemic (Trfhpx) mice, Hfeknockout mice, and B2m knockout mice. Interestingly, in Trfhpx homozygotes, DMT1 expression was strongly induced in the villus brush border when compared to control animals. This suggests that DMT1 expression is increased in response to iron deficiency in the erythron, even in the setting of systemic iron overload. In contrast, no increase was seen in DMT1 expression in animals with iron overload resembling human hemochromatosis. Therefore, it does not appear that changes in DMT1 levels are primarily responsible for iron loading in hemochromatosis.

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Abstract 528: ApoA-I Mimetic Peptide Treatment Improves Left Ventricular Diastolic Dysfunction and Decreases Iron Content in Coronary Plaques in Rabbits

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.35.suppl_1.528 ◽

2015 ◽

Vol 35 (suppl_1) ◽

Author(s):

Walid Nachar ◽

David Busseuil ◽

Yanfen Shi ◽

Teodora Mihalache-Avram ◽

Mélanie Mecteau ◽

...

Keyword(s):

Oxidative Stress ◽

Diastolic Dysfunction ◽

Iron Content ◽

Left Ventricular Diastolic Dysfunction ◽

Left Ventricular ◽

Heme Iron ◽

Mimetic Peptide ◽

Non Heme Iron ◽

Ventricular Diastolic Dysfunction ◽

Anti Oxidant

Introduction: Left ventricular diastolic dysfunction (LVDD) is characterized by the disturbance of ventricle’s performance due to its abnormal relaxation or to its increased stiffness. Hypertrophy, inflammation, fibrosis and oxidative stress are often associated with LVDD. Hypothesis: Given the reported anti-inflammatory and anti-oxidant properties of HDL, we assessed the potential of an apoA-I mimetic peptide to improve LVDD in a recently developed rabbit model. Methods: Forty-two rabbits were fed a normal diet (n=7) or a 0.5% cholesterol-enriched diet supplemented with vitamin D2 (n=35) for an average of 16 weeks. The hypercholesterolemic rabbits were randomised to receive 6 infusions of saline (n=11), 10 mg/kg (n=12) or 30 mg/kg of an apoA-I mimetic peptide over a period of 2 weeks. Serial echocardiography was used to assess LVDD. RT-qPCR and histological staining were performed on left ventricular homogenates and sections, respectively. Results: LVDD was improved in treated groups compared to saline as shown by decreased E/Em and increased Em/Am ratio assessed by echocardiography (p≤0.05). The apoA-I mimetic decreased transferrin receptor mRNA expression (p=0.039 for 10 mg/kg group) and increased ferritin heavy chain mRNA (p=0.053 for 30 mg/kg group) compared to saline. These changes were associated with a large decrease of non-heme iron content in LV sections of the treated groups (-90% in 10 mg/kg group, p≤0.01; -72% in 30 mg/kg group, p=0.1) compared to the saline-treated group as detected by Prussian blue staining. Significant reduction of RAM-11 macrophage staining was observed in treated groups compared to saline. A correlation was observed between iron and macrophage contents in LV (R=0.59 and p=0.0002). Most of the non-heme iron and macrophage stainings were seen in coronary arteries and plaques. Anti-oxidant enzyme (SOD2) mRNA was numerically increased in the 30 mg/kg group compared to saline (p=0.08). Conclusion: ApoA-I mimetic treatment improves LVDD. The observed decrease of left ventricular iron content may lead to reduce oxidative stress as iron contributes to reactive oxygen species formation. Further work is ongoing to validate whether decreased iron-mediated toxicity is a new benefit of apoA-I mimetic therapy.

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