scholarly journals Effect of fulvic and humic acids on iron and manganese homeostasis in rats

2017 ◽  
Vol 65 (1) ◽  
pp. 66-80 ◽  
Author(s):  
József Szabó ◽  
András Valentin Vucskits ◽  
Erzsébet Berta ◽  
Emese Andrásofszky ◽  
András Bersényi ◽  
...  
Keyword(s):  
Iron Content ◽  
Iron Homeostasis ◽  
Intestinal Content ◽  
Iron Level ◽  
Dietary Iron ◽  
Down Regulation ◽  
Fe And Mn ◽  
Liver And Kidney ◽  
Mn Concentration ◽  
Mn Concentrations

The objective of this study was to investigate the effects of fulvic acid (FA) and humic acid (HA) as the two main compounds of humic substances, separately on Fe and Mn homeostasis. Seventy-two male Wistar rats were randomly divided into 9 experimental groups. The control diet (AIN-93G formula) and diets supplemented with 0.1%, 0.2%, 0.4% and 0.8% HA or FA were fed for 26 days. Fe and Mn concentrations of the large intestinal content, liver, kidney, femur and hair were determined. No significant differences were observed in the production parameters. The effects of FA and HA on iron homeostasis were significantly different. FA proved to be a good iron source, and slightly increased the iron content of liver and kidney, but — up to a dietary iron level of 52.7 mg/kg — it did not influence the efficiency of iron absorption. Above a dietary iron level of 52.7 mg/kg down-regulation of Fe absorption can be assumed. HA significantly stimulated the iron uptake and there was no down-regulation of Fe absorption up to 0.8% dietary HA supplementation level (61.5 mg Fe/kg diet). In the HA groups the iron content of the liver and kidney decreased significantly, suggesting that in spite of the better Fe absorption, the HA—Fe complex does not provide iron to the investigated organs. Neither FA nor HA supplementation influenced the Fe content of the femur and hair and slightly decreased the Mn concentration in the large intestinal content. This effect was significant (with a 22.7% Mn concentration decrease) only at the HA supplementation rate of 0.8%. Neither FA nor HA influenced significantly the Mn concentrations of the liver, kidney and femur. The Mn concentration of the hair in rats receiving FA- or HA-supplemented diets was higher than in the control rats; however, this result needs further confirmation.

Leaching Characteristics of Manganese and Iron from Artificial Soil

2012 ◽  
Vol 518-523 ◽  
pp. 2568-2571
Author(s):  
Hong Ling Zhang ◽  
Li Na Sun ◽  
Tie Heng Sun
Keyword(s):  
Heavy Metals ◽  
Fly Ash ◽  
Sewage Sludge ◽  
Artificial Soil ◽  
Amorpha Fruticosa ◽  
Leaching Characteristics ◽  
Leaching Experiment ◽  
Fe And Mn ◽  
Mn Concentration ◽  
Mn Concentrations

A leaching experiment was carried out over a period of 90 days to determine the manganese (Mn) and iron (Fe) leaching characteristics from artificial soils composed of sewage sludge and fly ash. The leachates of artificial soils were collected every 15 days and the concentration of manganese and iron in leachates of the artificial soil was measured. Results showed that the concentration of Fe and Mn in leachates of artificial soils got to a stable level by the end of the experiment. Moreover, plant Robina pseudoacacia and Amorpha fruticosa had different effect on the leachate Fe and Mn concentration. Robina pseudoacacia resulted in higher leachate Fe concentration, while Amorpha fruticosa resulted in higher Mn concentration. However, the leachate Fe and Mn concentrations from artificial soils was high, and it will also be transported to the surface and ground water. Therefore, some measures should be taken to reduce the concentration of heavy metals in the leachates before these artificial soils being applied on the ecological rehabilitation in mine spoil areas.

scholarly journals Spontaneous iron overload in alpha-thalassemic mice

Blood ◽  
1984 ◽  
Vol 64 (1) ◽  
pp. 263-266
Author(s):  
DB Van Wyck ◽  
RA Popp ◽  
J Foxley ◽  
MH Witte ◽  
CL Witte ◽  
...  
Keyword(s):  
Iron Overload ◽  
Iron Content ◽  
Iron Homeostasis ◽  
Iron Absorption ◽  
Iron Concentration ◽  
Human Condition ◽  
Sham Operation ◽  
Liver And Kidney ◽  
Total Body ◽  
Chain Synthesis

Because clinical disorders of spontaneous iron overload have no experimental counterpart, we studied iron distribution (atomic absorption analysis) and intestinal absorption (59Fe) in mice with hereditary alpha-thalassemia. Mice heterozygous for a radiation-induced alpha-Hb gene deletion exhibit a mild hemolytic anemia, like the human condition, with microcytosis, reticulocytosis, splenomegaly, and chemical evidence of defective alpha-chain synthesis. Quantitative iron determination showed that total iron content in spleen, liver, and kidney, but not heart or lung, of adult alpha-thalassemic mice was greater (P less than .05) than that in unaffected littermates. Iron concentration was also increased in liver (P less than .001), spleen (P = .025), kidney (P = .058), and heart (P = .010); in general, the greater the iron concentration in liver, the greater that in spleen (r = .39, P = .009), kidney (r = .70, P less than .001), and heart (r = .46, P less than .001). In mice examined 8 months postoperatively, splenectomy, as compared to sham operation, significantly raised iron content in extrasplenic tissues, but did not affect total body iron. At 10–11 weeks of age, but no longer at 12–14 weeks, thalassemic mice showed higher rates of iron absorption than age-matched controls. Thus, alpha-thalassemic mice display an early occurring iron absorption defect, leading to a modest, sustained, nonprogressive iron overload, and thereby represent a valuable model for exploring disorders of iron homeostasis.

scholarly journals Investigation of heavy metals accumulation in the soil and pine trees

2019 ◽  
Vol 6 (1) ◽  
pp. 17-25
Author(s):  
Javad Kharkan ◽  
Mohammad Hossein Sayadi ◽  
Mohammad Reza Rezaei
Keyword(s):  
Heavy Metals ◽  
Transfer Factor ◽  
Land Uses ◽  
Significant Difference ◽  
Fe And Mn ◽  
Pine Trees ◽  
Accumulation Index ◽  
The City ◽  
Mn Concentration ◽  
Mn Concentrations

Background: Human activities related to workshops in the cities contribute to the release of heavy metals into the environment, which pose serious risks to the environment and to human health. The aim of the present study was to evaluate the concentration of lead (Pb), iron (Fe), and manganese (Mn) in the pine trees and soil in various land uses of Birjand city, Iran. Methods: The sampling stations were randomly selected from different land uses including parks, streets, carwashes, car repair shops, and car smooth shops in Birjand city. The pine trees (skin and leaves) and soil samples were collected from 15 stations located at different and uses in 2017. To determine the concentration of heavy metals, atomic absorption spectrometer (Contr AA 700) was used. Results: It was revealed that the mean concentration of Pb, Fe and Mn in residential soil was 1.79, 419.39, and 30.76 mg/kg, respectively. Moreover, the Pb, Fe, and Mn concentration in pine skin and leaves was 0.63 – 0.18, 23.05–9.84, and 10.05–3.13 mg/kg, respectively. The geo-accumulation index (Igeo) mean of the study areas demonstrated a descending trend for Fe (16.31 mg/kg) <Mn (8.86 mg/kg) <Pb (0.41 mg/kg). Pb showed the highest transfer factor in the parks and streets followed by Mn and Fe. In the car repair and smooth shops, the highest transfer factor pertained to Pb and the lowest one pertained to Fe. The statistical analysis indicated that there was a significant difference in the Fe and Mn concentrations among various land uses (P < 0.05). Conclusion: According to the results, the soils of car repair and smooth shops as well as carwashes in Birjand are becoming polluted by Pb, Fe, and Mn. Although, it does not threaten the city ecosystem, but with passage of time, these measures will be accumulated due to the soil alkalinity and will reach critical levels.

scholarly journals Management of Iron and Manganese Toxicities of Lentil Crops Grown in Central Chile

Agronomy ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2051
Author(s):  
Ramón Amigo ◽  
Ana María Méndez-Espinoza ◽  
Andrés R. Schwember ◽  
Jorge Cornejo ◽  
Ricardo Baettig ◽  
...  
Keyword(s):  
Dry Matter ◽  
Control Treatment ◽  
Mn Toxicity ◽  
Central Chile ◽  
Grain Yields ◽  
Fe And Mn ◽  
High Concentrations ◽  
Mn Concentration ◽  
Iron And Manganese ◽  
Mn Concentrations

Iron (Fe) and manganese (Mn) toxicity is a widespread problem in lentil production in the coastal dryland of Chile. Increasing the soil pH by liming with CaCO3 or incrementing grain yields through nitrogen fertilization can help the plants to reduce metal concentration. Thus, the main objective of this work was to evaluate two different fertilization strategies (lime (CaCO3) and nitrogen (N) additions) to reduce Fe and Mn toxicities in lentils. Lentils grown under field conditions with the highest Fe and Mn concentrations showed toxicity symptoms, but without grain yield reductions. In a pot experiment using the same soil as in the field with toxicity symptoms, the dry matter (DM) produced at the end of the trial was higher in the plants that received N while the lowest DM production was recorded in those plants treated with lime. In particular, higher root DM sustained the growth of the N-fertilized shoots, which also positively affected the grain yields being 33% higher than the control treatment (no fertilization addition). In the plants fertilized with N, the Fe and Mn levels in the shoots were lower than the control plants and those grown in soils treated with lime, but showed higher concentrations of Fe and Mn in roots. In parallel, roots exhibited high concentrations of Fe and Mn that were 13- and 9-fold higher than in the shoots. Additionally, a significant decrease of 29% in Mn concentration in the grains of plants treated with N was reported. Overall, our results suggest that an increase in DM of lentils by the addition of N can reduce the Mn concentration on leaves to a level that is likely under the threshold that causes toxicity in plant tissues. Finally, we conclude that the increase of Fe and Mn in the roots may be connected to the reduction of these metals on leaves.

scholarly journals MFehi adipose tissue macrophages compensate for tissue iron perturbations in mice

2018 ◽  
Vol 315 (3) ◽  
pp. C319-C329 ◽  
Author(s):  
Merla J. Hubler ◽  
Keith M. Erikson ◽  
Arion J. Kennedy ◽  
Alyssa H. Hasty
Keyword(s):  
Adipose Tissue ◽  
Iron Overload ◽  
Iron Content ◽  
Iron Homeostasis ◽  
Dietary Iron ◽  
Iron Cycling ◽  
Intracellular Iron ◽  
Iron Storage ◽  
Adipose Tissue Macrophages ◽  
Tissue Iron

Resident adipose tissue macrophages (ATMs) play multiple roles to maintain tissue homeostasis, such as removing excess free fatty acids and regulation of the extracellular matrix. The phagocytic nature and oxidative resiliency of macrophages not only allows them to function as innate immune cells but also to respond to specific tissue needs, such as iron homeostasis. MFehi ATMs are a subtype of resident ATMs that we recently identified to have twice the intracellular iron content as other ATMs and elevated expression of iron-handling genes. Although studies have demonstrated that iron homeostasis is important for adipocyte health, little is known about how MFehi ATMs may respond to and influence adipose tissue iron availability. Two methodologies were used to address this question: dietary iron supplementation and intraperitoneal iron injection. Upon exposure to high dietary iron, MFehi ATMs accumulated excess iron, whereas the iron content of MFelo ATMs and adipocytes remained unchanged. In this model of chronic iron excess, MFehi ATMs exhibited increased expression of genes involved in iron storage. In the injection model, MFehi ATMs incorporated high levels of iron, and adipocytes were spared iron overload. This acute model of iron overload was associated with increased numbers of MFehi ATMs; 17% could be attributed to monocyte recruitment and 83% to MFelo ATM incorporation into the MFehi pool. The MFehi ATM population maintained its low inflammatory profile and iron-cycling expression profile. These studies expand the field’s understanding of ATMs and confirm that they can respond as a tissue iron sink in models of iron overload.

Hepcidin-Independent Regulation of Dietary Iron Absorption

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 3853-3853
Author(s):  
Richard S. Ajioka ◽  
Ivana De Domenico ◽  
James P. Kushner
Keyword(s):  
Iron Content ◽  
Iron Homeostasis ◽  
Iron Absorption ◽  
Hematological Parameters ◽  
Transferrin Saturation ◽  
Inverse Correlation ◽  
Dietary Iron ◽  
Competitive Binding Assay ◽  
Proximal Small Bowel ◽  
Serum Hepcidin

Abstract Iron homeostasis in mammals is maintained at the level of iron absorption by the gut. Hepcidin plays a central role in homeostasis by binding to ferroportin and regulating cellular iron export. We found that mice weaned onto diets ranging from 35–350 mg Fe/kg for a period of 4 wk did not change body iron levels as measured by organ iron content and hematological parameters. Direct measure of absorption of 59Fe administered by gavage revealed an inverse correlation between dietary iron content and absorption. Gavage experiments were done following a 4h fast when the stomach and proximal small bowel were free of dietary content. Although iron absorption changed, liver expression of hepcidin mRNA did not. We measured the absorptive response in mice weaned onto diets containing 35 mg Fe/kg for 4 wk and abruptly changed to 350 mg Fe/kg. There was no change in iron absorption at day 1 but by day 3 absorption was reduced nearly 3-fold compared to controls and remained at this level for at least 7d. During this time neither liver nor spleen iron content changed but transferrin saturation increased approximately 1.5-fold. Most importantly, serum hepcidin levels, measured by a competitive binding assay (De Domenico et al. Cell Metab.2008, 8:146–156), were unchanged. Mice were then changed from diets containing 350 mg Fe/kg to diets containing 35 mg Fe/kg. Within 24h mice increased absorption of 59Fe 3-fold. Elevated absorption continued for at least 3d, declined by 7d and at 14d was at a level found in mice maintained on a diet containing 35 mg Fe/kg. During this period there was no change in organ iron content or in transferrin saturation. Serum hepcidin did not change on day 1, but was reduced by approximately 40% on days 3 through 7. Increased iron absorption could be attributed in part to increased expression of Dmt1 but no change in ferroportin message was detected. Enterocyte ferritin levels doubled on day 1 but returned to control levels on days 3 through 7. Finally, mice with a targeted disruption of the hepcidin gene were challenged with an abrupt reduction in dietary iron content and absorption increased approximately 3-fold. These data suggest that iron absorption can respond to changes in dietary iron content independent of hepcidin and that response to changes in luminal iron content are at the level of uptake and storage in a manner intrinsic to the enterocyte.

A SURVEY OF MATERNAL AND FETAL TISSUE ZINC, IRON, MANGANESE AND SELENIUM CONCENTRATIONS IN BOVINE

1989 ◽  
Vol 69 (1) ◽  
pp. 151-159 ◽  
Author(s):  
S. R. GOONERATNE ◽  
D. A. CHRISTENSEN
Keyword(s):  
Key Words ◽  
Fetal Liver ◽  
Fetal Tissue ◽  
Adult Cattle ◽  
Fetal Tissues ◽  
Fe And Mn ◽  
Bovine Fetuses ◽  
Liver And Kidney ◽  
Iron Manganese ◽  
Mn Concentrations

Whole bovine fetuses and liver and kidney from corresponding dams, from nonpregnant cows, from heifers, and from steers were collected during routine slaughter operation at a local packing plant in Saskatoon. Fetal liver, kidney, heart and brain, and liver and kidney from adult cattle were analyzed for Zn, Fe, and in some cases for Mn and Se. Pregnancy did not significantly alter the dam liver Zn, Fe, and Mn concentrations. Fetal liver Zn, Fe and Se concentrations were several-fold higher and Mn concentrations lower than those in liver from corresponding dams. Liver Se concentrations were significantly lower in the nonpregnant cows, of which 34% originated from gray black and muskeg soils in Saskatchewan. Liver Se concentrations of fetuses and pregnant cows originating from muskeg and gray (wooded) soils were significantly lower than those from other areas of Saskatchewan. Correlations between Zn, Fe, Mn, Se and Cu between and within dam and fetal tissues were low, except for dam and fetal liver Se concentration (r = 0.65). Possible interactions between these micronutrients in both the dam and fetus and sources of biases which occur in this type of a survey are discussed. Key words: Zinc, iron, maganese, selenium, cattle, pregnancy

scholarly journals Spontaneous iron overload in alpha-thalassemic mice

Blood ◽  
1984 ◽  
Vol 64 (1) ◽  
pp. 263-266 ◽  
Author(s):  
DB Van Wyck ◽  
RA Popp ◽  
J Foxley ◽  
MH Witte ◽  
CL Witte ◽  
...  
Keyword(s):  
Iron Overload ◽  
Iron Content ◽  
Iron Homeostasis ◽  
Iron Absorption ◽  
Iron Concentration ◽  
Human Condition ◽  
Sham Operation ◽  
Liver And Kidney ◽  
Total Body ◽  
Chain Synthesis

Abstract Because clinical disorders of spontaneous iron overload have no experimental counterpart, we studied iron distribution (atomic absorption analysis) and intestinal absorption (59Fe) in mice with hereditary alpha-thalassemia. Mice heterozygous for a radiation-induced alpha-Hb gene deletion exhibit a mild hemolytic anemia, like the human condition, with microcytosis, reticulocytosis, splenomegaly, and chemical evidence of defective alpha-chain synthesis. Quantitative iron determination showed that total iron content in spleen, liver, and kidney, but not heart or lung, of adult alpha-thalassemic mice was greater (P less than .05) than that in unaffected littermates. Iron concentration was also increased in liver (P less than .001), spleen (P = .025), kidney (P = .058), and heart (P = .010); in general, the greater the iron concentration in liver, the greater that in spleen (r = .39, P = .009), kidney (r = .70, P less than .001), and heart (r = .46, P less than .001). In mice examined 8 months postoperatively, splenectomy, as compared to sham operation, significantly raised iron content in extrasplenic tissues, but did not affect total body iron. At 10–11 weeks of age, but no longer at 12–14 weeks, thalassemic mice showed higher rates of iron absorption than age-matched controls. Thus, alpha-thalassemic mice display an early occurring iron absorption defect, leading to a modest, sustained, nonprogressive iron overload, and thereby represent a valuable model for exploring disorders of iron homeostasis.

scholarly journals Ferric uptake regulator (Fur) reversibly binds a [2Fe-2S] cluster to sense intracellular iron homeostasis in Escherichia coli

2020 ◽  
Vol 295 (46) ◽  
pp. 15454-15463 ◽  
Author(s):  
Chelsey R. Fontenot ◽  
Homyra Tasnim ◽  
Kathryn A. Valdes ◽  
Codrina V. Popescu ◽  
Huangen Ding
Keyword(s):  
Escherichia Coli ◽  
Iron Content ◽  
Iron Homeostasis ◽  
Ferric Uptake Regulator ◽  
Intracellular Iron ◽  
Free Iron ◽  
E Coli ◽  
Genes Encoding ◽  
Fur Protein ◽  
Mutant Cells

The ferric uptake regulator (Fur) is a global transcription factor that regulates intracellular iron homeostasis in bacteria. The current hypothesis states that when the intracellular “free” iron concentration is elevated, Fur binds ferrous iron, and the iron-bound Fur represses the genes encoding for iron uptake systems and stimulates the genes encoding for iron storage proteins. However, the “iron-bound” Fur has never been isolated from any bacteria. Here we report that the Escherichia coli Fur has a bright red color when expressed in E. coli mutant cells containing an elevated intracellular free iron content because of deletion of the iron–sulfur cluster assembly proteins IscA and SufA. The acid-labile iron and sulfide content analyses in conjunction with the EPR and Mössbauer spectroscopy measurements and the site-directed mutagenesis studies show that the red Fur protein binds a [2Fe-2S] cluster via conserved cysteine residues. The occupancy of the [2Fe-2S] cluster in Fur protein is ∼31% in the E. coli iscA/sufA mutant cells and is decreased to ∼4% in WT E. coli cells. Depletion of the intracellular free iron content using the membrane-permeable iron chelator 2,2´-dipyridyl effectively removes the [2Fe-2S] cluster from Fur in E. coli cells, suggesting that Fur senses the intracellular free iron content via reversible binding of a [2Fe-2S] cluster. The binding of the [2Fe-2S] cluster in Fur appears to be highly conserved, because the Fur homolog from Hemophilus influenzae expressed in E. coli cells also reversibly binds a [2Fe-2S] cluster to sense intracellular iron homeostasis.

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