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INVESTIGATION OF FACTORS POTENTIALLY ASSOCIATED WITH SERUM FERRITIN CONCENTRATIONS IN THE BLACK RHINOCEROS ( DICEROS BICORNIS) USING A VALIDATED RHINOCEROS-SPECIFIC ASSAY. J Zoo Wildl Med 2019; 49:297-306. [PMID: 29900786 DOI: 10.1638/2017-0131.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Iron overload disorder (IOD) can lead to organ dysfunction and may exacerbate other diseases in the critically endangered black rhinoceros ( Diceros bicornis). It is important to develop methods for monitoring the progression of iron storage (hemosiderosis), diagnosing the disease, and evaluating treatments in this species. Traditionally, an equine enzyme immunoassay (EIA) was used to measure rhinoceros ferritin, a serum protein correlated to iron stores. The goal of this study was to validate a rhinoceros-specific assay and investigate factors potentially associated with ferritin concentrations in black rhinoceros. A ferritin EIA developed for Sumatran rhinoceros was validated for black rhinoceros via Western blot analysis of liver ferritin and confirmed parallelism of serum samples to the EIA standard curve and used to analyze serum samples ( n = 943) collected from 36 black rhinoceros (<1-33 yr) at 14 U.S. institutions. Mean (±SEM) serum ferritin concentration was 6,738 ± 518 ng/ml (range: 85-168,451 ng/ml). Concentrations differed among individuals with eastern black rhinoceros (7,444 ± 1,130 ng/ml) having a higher mean ferritin than southern black rhinoceros (6,317 ± 505 ng/ml; P < 0.05) and higher mean values in wild-born (11,110 ± 1,111 ng/ml) than captive-born individuals (3,487 ± 293 ng/ml; P < 0.05). Ferritin concentrations did not differ between young rhinoceros (<5 yr old; 2,163 ± 254 ng/ml) and adults (7,623 ± 610 ng/ml) and were not correlated with age ( r = 0.143) or time in captivity ( r = 0.146, wild born; r = 0.104, all animals). Ferritin concentration was not impacted by sex (female: 2,086 ± 190 ng/ml; male: 8,684 ± 717 ng/ml), date, month, or season of collection ( P > 0.05). Data indicate ferritin concentrations are variable and not necessarily associated with IOD; ferritin is not recommended for diagnosing or monitoring IOD in black rhinoceros.
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SERUM FERRITIN CONCENTRATION IS NOT A RELIABLE BIOMARKER OF IRON OVERLOAD DISORDER PROGRESSION OR HEMOCHROMATOSIS IN THE SUMATRAN RHINOCEROS (DICERORHINUS SUMATRENSIS). J Zoo Wildl Med 2019; 48:645-658. [PMID: 28920821 DOI: 10.1638/2017-0010.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The aim of this study was to determine if ferritin is a reliable biomarker of iron overload disorder (IOD) progression and hemochromatosis in the Sumatran rhinoceros (Dicerorhinus sumatrensis) by developing a species-specific ferritin assay and testing historically banked samples collected from rhinos that did and did not die of hemochromatosis. Ferritin extracted from Sumatran rhino liver tissue was used to generate antibodies for the Enzyme Immunoassay. Historically banked Sumatran rhino serum samples (n = 298) obtained from six rhinos in US zoos (n = 290); five rhinos at the Sumatran Rhino Conservation Centre in Sungai Dusun, Malaysia (n = 5); and two rhinos in Sabah, Malaysia (n = 3) were analyzed for ferritin concentrations. Across all US zoo samples, serum ferritin concentrations ranged from 348 to 7,071 ng/ml, with individual means ranging from 1,267 (n = 25) to 2,604 ng/ml (n = 36). The ferritin profiles were dynamic, and all rhinos exhibited spikes in ferritin above baseline during the sampling period. The rhino with the highest mean ferritin concentration did not die of hemochromatosis and exhibited only mild hemosiderosis postmortem. A reproductive female exhibited decreases and increases in serum ferritin concurrent with pregnant and nonpregnant states, respectively. Mean (±SD) serum ferritin concentration for Sumatran rhinos in Malaysia was high (4,904 ± 4,828 ng/ml) compared to that for US zoo rhinos (1,835 ± 495 ng/ml). However, those in Sabah had lower ferritin concentrations (1,025 ± 52.7 ng/ml) compared to those in Sungai Dusun (6,456 ± 4,941 ng/ml). In conclusion, Sumatran rhino serum ferritin concentrations are dynamic, and increases often are not associated with illness or hemochromatosis. Neither a specific pattern nor the individual's overall mean ferritin concentration can be used to accurately assess IOD progression or diagnose hemochromatosis in this rhino species.
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Sheriff SA, Devaki T. Lycopene stabilizes liver function duringd-galactosamine/lipopolysaccharide induced hepatitis in rats. JOURNAL OF TAIBAH UNIVERSITY FOR SCIENCE 2018. [DOI: 10.1016/j.jtusci.2013.01.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Theil EC, Tosha T, Behera RK. Solving Biology's Iron Chemistry Problem with Ferritin Protein Nanocages. Acc Chem Res 2016; 49:784-91. [PMID: 27136423 DOI: 10.1021/ar500469e] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Ferritins reversibly synthesize iron-oxy(ferrihydrite) biominerals inside large, hollow protein nanocages (10-12 nm, ∼480 000 g/mol); the iron biominerals are metabolic iron concentrates for iron protein biosyntheses. Protein cages of 12- or 24-folded ferritin subunits (4-α-helix polypeptide bundles) self-assemble, experimentally. Ferritin biomineral structures differ among animals and plants or bacteria. The basic ferritin mineral structure is ferrihydrite (Fe2O3·H2O) with either low phosphate in the highly ordered animal ferritin biominerals, Fe/PO4 ∼ 8:1, or Fe/PO4 ∼ 1:1 in the more amorphous ferritin biominerals of plants and bacteria. While different ferritin environments, plant bacterial-like plastid organelles and animal cytoplasm, might explain ferritin biomineral differences, investigation is required. Currently, the physiological significance of plant-specific and animal-specific ferritin iron minerals is unknown. The iron content of ferritin in living tissues ranges from zero in "apoferritin" to as high as ∼4500 iron atoms. Ferritin biomineralization begins with the reaction of Fe(2+) with O2 at ferritin enzyme (Fe(2+)/O oxidoreductase) sites. The product of ferritin enzyme activity, diferric oxy complexes, is also the precursor of ferritin biomineral. Concentrations of Fe(3+) equivalent to 2.0 × 10(-1) M are maintained in ferritin solutions, contrasting with the Fe(3+) Ks ∼ 10(-18) M. Iron ions move into, through, and out of ferritin protein cages in structural subdomains containing conserved amino acids. Cage subdomains include (1) ion channels for Fe(2+) entry/exit, (2) enzyme (oxidoreductase) site for coupling Fe(2+) and O yielding diferric oxy biomineral precursors, and (3) ferric oxy nucleation channels, where diferric oxy products from up to three enzyme sites interact while moving toward the central, biomineral growth cavity (12 nm diameter) where ferric oxy species, now 48-mers, grow in ferric oxy biomineral. High ferritin protein cage symmetry (3-fold and 4-fold axes) and amino acid conservation coincide with function, shown by amino acid substitution effects. 3-Fold symmetry axes control Fe(2+) entry (enzyme catalysis of Fe(2+)/O2 oxidoreduction) and Fe(2+) exit (reductive ferritin mineral dissolution); 3-fold symmetry axes influence Fe(2+)exit from dissolved mineral; bacterial ferritins diverge slightly in Fe/O2 reaction mechanisms and intracage paths of iron-oxy complexes. Biosynthesis rates of ferritin protein change with Fe(2+) and O2 concentrations, dependent on DNA-binding, and heme binding protein, Bach 1. Increased cellular O2 indirectly stabilizes ferritin DNA/Bach 1 interactions. Heme, Fe-protoporphyrin IX, decreases ferritin DNA-Bach 1 binding, causing increased ferritin mRNA biosynthesis (transcription). Direct Fe(2+) binding to ferritin mRNA decreases binding of an inhibitory protein, IRP, causing increased ferritin mRNA translation (protein biosynthesis). Newly synthesized ferritin protein consumes Fe(2+) in biomineral, decreasing Fe(2)(+) and creating a regulatory feedback loop. Ferritin without iron is "apoferritin". Iron removal from ferritin, experimentally, uses biological reductants, for example, NADH + FMN, or chemical reductants, for example, thioglycolic acid, with Fe(2+) chelators; physiological mechanism(s) are murky. Clear, however, is the necessity of ferritin for terrestrial life by conferring oxidant protection (plants, animals, and bacteria), virulence (bacteria), and embryonic survival (mammals). Future studies of ferritin structure/function and Fe(2+)/O2 chemistry will lead to new ferritin uses in medicine, nutrition, and nanochemistry.
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Affiliation(s)
- Elizabeth C. Theil
- Children’s Hospital Oakland Research Institute, Oakland, California 94609, United States
- Department of Structural
and Molecular Biochemistry, North Carolina State University, Raleigh, North Carolina 27695-7313, United States
| | - Takehiko Tosha
- Children’s Hospital Oakland Research Institute, Oakland, California 94609, United States
- Department of Structural
and Molecular Biochemistry, North Carolina State University, Raleigh, North Carolina 27695-7313, United States
| | - Rabindra K. Behera
- Children’s Hospital Oakland Research Institute, Oakland, California 94609, United States
- Department of Structural
and Molecular Biochemistry, North Carolina State University, Raleigh, North Carolina 27695-7313, United States
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Tatsumi H, Tsuchiya Y, Sakamoto K. Sensitive electrochemical measurement of hydroxyl radical generation induced by the xanthine-xanthine oxidase system. Anal Biochem 2014; 467:22-7. [PMID: 25180984 DOI: 10.1016/j.ab.2014.08.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 08/20/2014] [Accepted: 08/22/2014] [Indexed: 11/25/2022]
Abstract
A sensitive electrochemical measurement system for hydroxyl radical (OH) was developed using enzyme-catalyzed signal amplification. In the presence of 2,6-xylenol as a trapping agent, glucose as a substrate, and pyrroloquinoline quinone-dependent glucose dehydrogenase (PQQ-GDH) as a catalyst, the amperometric signal of the trapping adduct 2,6-dimethylhydroquinone (DMHQ) produced by the hydroxylation of 2,6-xylenol was able to be amplified and detected sensitively. The limit of detection (signal/noise [S/N]=3) for DMHQ was 1 nM. There was no significant interference from urate and other oxidizable compounds in the reaction mixture at the applied potential of 0V versus Ag/AgCl. This method was employed to observe the OH generation induced by the xanthine-xanthine oxidase (XO) system. The reaction rates of the DMHQ production induced from the xanthine-XO system in the presence and absence of various Fe(III) complexes and proteins were compared. Those with a free coordination site on the Fe atom effectively enhanced the OH generation.
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Affiliation(s)
- Hirosuke Tatsumi
- Department of Chemistry, Faculty of Science, Shinshu University, Matsumoto, Nagano 390-8621, Japan.
| | - Yui Tsuchiya
- Department of Chemistry, Faculty of Science, Shinshu University, Matsumoto, Nagano 390-8621, Japan
| | - Koichi Sakamoto
- Department of Chemistry, Faculty of Science, Shinshu University, Matsumoto, Nagano 390-8621, Japan
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Jayaraman J, Jesudoss VAS, Menon VP, Namasivayam N. Anti-inflammatory role of naringenin in rats with ethanol induced liver injury. Toxicol Mech Methods 2013; 22:568-76. [PMID: 22900548 DOI: 10.3109/15376516.2012.707255] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The aim of the study was to investigate the antiinflammatory effects of naringenin in rats induced liver damage by exposure to ethanol. Rats were divided into four groups, groups 1 and 2 received isocaloric glucose; groups 3 and 4 received 20% ethanol equivalent to 6 g/kg body weight everyday for the total experimental period of 60 days. In addition, groups 2 and 4 were supplemented with naringenin (50 mg/kg p.o.) everyday for the last 30 days of the experiment. The results showed significantly elevated levels/activities/expression of serum aspartate and alanine transaminases, iron, ferritin, transforming growth factor-alpha (TNF-α), interleukin-6 (IL-6), nuclear factor-kappa B (NF-κB), cyclooxygenase-2 (COX-2), macrophage inflammatory protein 2 (MIP-2) and CD14 in ethanol fed rats as compared to those of the control. Ethanol-fed rats exhibited increased staining for the presence of inducible nitric oxide (iNOS) protein adducts in the liver. Supplementation with naringenin for the last 30 days to ethanol-fed rats, significantly decreased the levels/activities/expression of serum aspartate and alanine transaminases, iron, ferritin, TNF-α, IL-6, NF-κB, COX-2, MIP-2, CD14 and iNOS protein adducts in the liver as compared to the untreated ethanol fed rats. The inhibition of TNF-α, IL-6, NF-κB, COX-2, MIP-2, iNOS and CD14 by naringenin may contribute to its antiinflammatory activity in ethanol fed rats.
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Affiliation(s)
- Jayachitra Jayaraman
- Faculty of Science, Department of Biochemistry and Biotechnology, Annamalai University, Annamalainagar, Tamilnadu, India
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Lapenna D, De Gioia S, Ciofani G, Cuccurullo F. Captopril Induces Iron Release From Ferritin and Oxidative Stress. J Pharm Pharmacol 2011. [DOI: 10.1111/j.2042-7158.1995.tb05734.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Abstract
Captopril has been reported to possess reducing and iron-binding properties, which could favour iron delocalization from ferritin and oxidative stress.
In the present paper, we have found that the drug was effectively capable of inducing a significant mobilization of ferritin iron, which was apparently superoxide anion-independent. Once released from ferritin as a result of captopril action, iron became free in the reduced form and could induce oxidant damage, as evaluated by deoxyribose-oxidative degradation. This phenomenon was not antagonized by the reported oxygen radical-scavenging properties of the drug.
These data indicate that captopril is not always an antioxidant drug, and suggest that it may act as a pro-oxidant in the presence of ferritin in-vivo.
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Affiliation(s)
- Domenico Lapenna
- Cattedra di Medicina Interna, Universitá degli Studi ‘G. D’ Annunzio’, Facoltá di Medicina e Chirurgia, Chieti, Italy
| | - Sergio De Gioia
- Cattedra di Medicina Interna, Universitá degli Studi ‘G. D’ Annunzio’, Facoltá di Medicina e Chirurgia, Chieti, Italy
| | - Giuliano Ciofani
- Cattedra di Medicina Interna, Universitá degli Studi ‘G. D’ Annunzio’, Facoltá di Medicina e Chirurgia, Chieti, Italy
| | - Franco Cuccurullo
- Cattedra di Medicina Interna, Universitá degli Studi ‘G. D’ Annunzio’, Facoltá di Medicina e Chirurgia, Chieti, Italy
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Fielding CJ, Bothwell TH, Cook JD, Crichton RR, Crosby WH, Dallman PR, Drysdale JW, Hallberg L, Halliday J, Harrison PM, Hershko C, Layrisse M, Ramsay WNM, Worwood M. Preparation, characterization and storage of human ferritin for use as a standard for the assay of serum ferritin. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1365-2257.1984.tb00541.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Kumar K. Iron Assay and Size Exclusion High Performance Liquid Chromatography of Ferritin and Magnetoferritin. J LIQ CHROMATOGR R T 2006. [DOI: 10.1080/10826079708005836] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Krishan Kumar
- a Bracco Research USA, Inc. , 305 College Road East, Princeton, NJ, 08540
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Makris DP, Psarra E, Kallithraka S, Kefalas P. The effect of polyphenolic composition as related to antioxidant capacity in white wines. Food Res Int 2003. [DOI: 10.1016/s0963-9969(03)00075-9] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Krasko A, Schröder HC, Batel R, Grebenjuk VA, Steffen R, Müller IM, Müller WEG. Iron induces proliferation and morphogenesis in primmorphs from the marine sponge Suberites domuncula. DNA Cell Biol 2002; 21:67-80. [PMID: 11879581 DOI: 10.1089/10445490252810320] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Dissociated cells from marine demosponges retain their proliferation capacity if they are allowed to form special aggregates, the primmorphs. On the basis of incorporation studies and septin gene expression, we show that Fe3+ ions are required for the proliferation of cells in primmorphs from Suberites domuncula. In parallel, Fe3+ induced the expression of ferritin and strongly stimulated the synthesis of spicules. This result is supported by the finding that the enzymatic activity of silicatein, converting organosilicon to silicic acid, depends on Fe3+. Moreover, the expression of a scavenger receptor molecule, possibly involved in the morphology of spicules, depends on the presence of Fe3+. We conclude that iron is an essential factor in proliferative and morphogenetic processes in primmorphs.
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Affiliation(s)
- Anatoli Krasko
- Institut für Physiologische Chemie, Abteilung Angewandte Molekularbiologie, Universität, Mainz, Germany
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Abstract
BACKGROUND/AIMS The recovery from iron overload is hampered by the limited number of pathways and therapeutic agents available for the augmentation of iron secretion/excretion. The present study was aimed to investigate the process of iron storage and release by cultured human hepatoma cells, the role of transferrin receptors and ferritin in this process as well as the effect of iron chelators. METHODS We followed the acquisition, storage and release of iron by cultured cells HepG2 and Hep3B by biochemical means and electron microscopy. RESULTS The uptake of iron from diferric transferrin (Trf) was extremely low, while iron as ferric-ammonium-citrate (FAC) was taken up readily, especially by Hep3B cells. Up to 80% of the iron taken up by hepatoma cells was released to the medium. The rate of spontaneous iron release depended on the extent of iron loading. ApoTrf and deferoxamine facilitated release after 1- and 7-day iron-exposure. Up to a third of the radio-iron released from the cells was associated with ferritin. The release of ferritin-iron was not enhanced by either deferoxamine or Trf. CONCLUSIONS Ferritin-iron release appeared to be an important mechanism of iron discarding in cultured human hepatoma cells, independent of the activity of chelating agents.
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Affiliation(s)
- Mark Hirsh
- The Pediatric Research and Electron Microscopy Unit, B Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, P.O. Box 9649, Haifa 31096, Israel
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Rodríguez MC, Puy Sáiz M, Carbonell T, Mitjavila MT. Local and systemic responses to iron-dextran injected into a granuloma pouch in the rat. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 1999; 134:42-8. [PMID: 10402058 DOI: 10.1016/s0022-2143(99)90052-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Many inflammatory processes are accompanied by anemia and repeated hemorrhages, but the local and systemic effect of the iron present in the inflamed area and the availability of this iron are not known. The experimental model used to mimic the above situation was the carrageenan-induced granuloma in rats with simultaneous iron-dextran injection into the granuloma pouch. We studied the effect of iron-dextran on leukocytes from the inflammatory exudate and the location of iron in the granuloma tissue. We also evaluated the systemic responses by studying several iron parameters in blood and in iron-storage organs. The results showed a reduction in the number of leukocytes present in the exudate and a reduction in their viability and also extensive damage to the granuloma tissue, essentially to macrophages, caused by local iron-induced oxidative stress. A small percentage of iron reaches the systemic circulation, and this is eventually stored in the liver and spleen as hemosiderin, which is unlikely to have any effect on anemia. In spite of its local toxicity, the accumulation of iron in inflamed areas can be interpreted as a protective mechanism against systemic oxidative radical reactions induced by iron mobilization.
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Affiliation(s)
- M C Rodríguez
- Departament de Fisiologia, Facultat de Biologia, Universitat de Barcelona, Spain
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Akpanabiatu MI, Ayatse JO, Ifere GO, Itam EH, Umoh EB. The effect of changing living standards on iron status in pregnancy in Calabar urban. J Trace Elem Med Biol 1999; 12:201-4. [PMID: 10365371 DOI: 10.1016/s0946-672x(99)80058-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Reduced meat intake is often associated with iron deficiency anaemia. Reduced meat intake that arose from the frugality associated with a prolonged period of national economic reorientation policy, known as the "structural adjustment programme" (SAP), may have placed iron-stress on pregnancy in particular. Iron status of pre-SAP and SAP pregnancies were established from measurement of the haematological values of subjects. Indices such as haemoglobin (Hb), packed cell volume, serum Fe were lower in pregnancy especially during SAP. However, SAP pregnancy serum ferritin did not respond significantly to iron depletion. Unlike PCV, Total Iron Binding Capacity (TIBC) and serum transferrin values showed a reverse behaviour. The level of these values, however, portends a toll exerted on body iron status in pregnancy associated with reduced haem iron intake. The changes in these values did not, however, lead to any over symptoms of iron deficiency probably because increased sea food (molluscs) consumption ameliorates the iron-toll from low absorbed non-haem iron. For lower income rural women in non-coastal areas, the absence of seafood in their diets exacerbates the low iron status in Pregnancy.
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Affiliation(s)
- M I Akpanabiatu
- Department of Biochemistry, College of Medical Sciences, University of Calabar, Nigeria
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16
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Anandan R, Devaki T. Hepatoprotective effect of Picrorrhiza kurroa on tissue defence system in d-galactosamine-induced hepatitis in rats. Fitoterapia 1999. [DOI: 10.1016/s0367-326x(98)00022-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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17
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LEE BEOMJUN, HENDRICKS DELOYG. Metal-Catalyzed Oxidation of Ascorbate, Deoxyribose and Linoleic Acid as Affected by Phytic Acid in a Model System. J Food Sci 1997. [DOI: 10.1111/j.1365-2621.1997.tb15010.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Le Brun NE, Andrews SC, Moore GR, Thomson AJ. Interaction of nitric oxide with non-haem iron sites of Escherichia coli bacterioferritin: reduction of nitric oxide to nitrous oxide and oxidation of iron(II) to iron(III). Biochem J 1997; 326 ( Pt 1):173-9. [PMID: 9337865 PMCID: PMC1218651 DOI: 10.1042/bj3260173] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The bacterioferritin (BFR) of Escherichia coli consists of 24 identical subunits, each containing a dinuclear metal-binding site consisting of two histidines and four carboxylic acid residues. Earlier studies showed that the characterization of iron binding to BFR could be aided by EPR analysis of iron-nitrosyl species resulting from the addition of NO to the protein [Le Brun, Cheesman, Andrews, Harrison, Guest, Moore and Thomson (1993) FEBS Lett. 323, 261-266]. We now report data from gas chromatographic head space analysis combined with EPR spectroscopy to show that NO is not an inert probe: iron(II)-BFR catalyses the reduction of NO to N2O, resulting in oxidation of iron(II) at the dinuclear centre and the subsequent detection of mononuclear iron(III). In the presence of excess reductant (sodium ascorbate), iron(II)-BFR also catalyses the reduction of NO to N2O, giving rise to three mononuclear iron-nitrosyl species which are detectable by EPR. One of these, a dinitrosyl-iron complex of S = 1/2, present at a maximum of one per subunit, is shown by EPR studies of site-directed variants of BFR not to be located at the dinuclear centre. This is consistent with a proposal that the diferric form of the centre is unstable and breaks down to form mononuclear iron species.
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Affiliation(s)
- N E Le Brun
- Centre for Metalloprotein Spectroscopy and Biology, School of Chemical Sciences, University of East Anglia, Norwich, U.K
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Qiu J, Song J, Gao H. Direct determination of iron in ferritin using the polarographic catalytic current. Anal Bioanal Chem 1996; 356:101-3. [PMID: 15048378 DOI: 10.1007/s0021663560101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/1995] [Revised: 12/13/1995] [Accepted: 12/17/1995] [Indexed: 04/29/2023]
Abstract
A new method for the determination of iron in ferritin using the polarographic catalytic current has been developed. Iron is released in NaOH and triethanolamine (TEA) solution and subsequently determined based on the polarographic catalytic wave in the presence of bromate with the peak potential of -1.0 V (vs.SCE). The 2.5-derivative peak height of iron is linearly proportional to its concentration in the range of 8.0 x 10(-8)-1.0 x 10(-6) g/ml with a correlation coefficient of 0.9991. The method has been applied to the determination of iron in human fetal liver and horse-spleen ferritin and the recovery is 95-112%.
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Affiliation(s)
- J Qiu
- Institute of Electroanalytical Chemistry, Northwest University, 710069, Xian, People's Republic of China
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Le Brun NE, Andrews SC, Guest JR, Harrison PM, Moore GR, Thomson AJ. Identification of the ferroxidase centre of Escherichia coli bacterioferritin. Biochem J 1995; 312 ( Pt 2):385-92. [PMID: 8526846 PMCID: PMC1136274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The bacterioferritin (BFR) of Escherichia coli takes up iron in the ferrous form and stores it within its central cavity as a hydrated ferric oxide mineral. The mechanism by which oxidation of iron (II) occurs in BFR is largely unknown, but previous studies indicated that there is ferroxidase activity associated with a site capable of forming a dinuclear-iron centre within each subunit [Le Brun, Wilson, Andrews, Harrison, Guest, Thomson and Moore (1993) FEBS Lett. 333, 197-202]. We now report site-directed mutagenesis experiments based on a putative dinuclear-metal-ion-binding site located within the BFR subunit. The data reveal that this dinuclear-iron centre is located at a site within the four-alpha-helical bundle of each subunit of BFR, thus identified as the ferroxidase centre of BFR. The metal-bound form of the centre bears a remarkable similarity to the dinuclear-iron sites of the hydroxylase subunit of methane mono-oxygenase and the R2 subunit of ribonucleotide reductase. Details of how the dinuclear centre of BFR is involved in the oxidation mechanism were investigated by studying the inhibition of iron (II) oxidation by zinc (II) ions. Data indicate that zinc (II) ions bind at the ferroxidase centre of apo-BFR in preference to iron (II), resulting in a dramatic reduction in the rate of oxidation. The mechanism of iron (II) oxidation is discussed in the light of this and previous work.
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Affiliation(s)
- N E Le Brun
- Centre for Metalloprotein Spectroscopy and Biology, School of Chemical Sciences, University of East Anglia, Norwich, U.K
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21
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Andrews SC, Le Brun NE, Barynin V, Thomson AJ, Moore GR, Guest JR, Harrison PM. Site-directed replacement of the coaxial heme ligands of bacterioferritin generates heme-free variants. J Biol Chem 1995; 270:23268-74. [PMID: 7559480 DOI: 10.1074/jbc.270.40.23268] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The bacterioferritin (BFR) of Escherichia coli is a heme-containing iron storage molecule. It is composed of 24 identical subunits, which form a roughly spherical protein shell surrounding a central iron storage cavity. Each of the 12 heme moieties of BFR possesses bis-methionine axial ligation, a heme coordination scheme so far only found in bacterioferritins. Members of the BFR family contain three partially conserved methionine residues (excluding the initiating methionine) and in this study each was substituted by leucine and/or histidine. The Met52 variants were devoid of heme, whereas the Met31 and Met86 variants possessed full heme complements and were spectroscopically indistinguishable from wild-type BFR. The heme-free Met52 variants appeared to be correctly assembled and were capable of accumulating iron both in vivo and in vitro. No major differences were observed in the overall rate of iron accumulation for BFR-M52H, BFR-M52L, and the wild-type protein. The iron contents of the Met52 variants, as isolated, were at least 4 times greater than for wild-type BFR. This study is consistent with the reported location of the BFR heme site at the 2-fold axis and shows that heme is unnecessary for BFR assembly and iron uptake.
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Affiliation(s)
- S C Andrews
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, United Kingdom
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22
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Hudson AJ, Andrews SC, Hawkins C, Williams JM, Izuhara M, Meldrum FC, Mann S, Harrison PM, Guest JR. Overproduction, purification and characterization of the Escherichia coli ferritin. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 218:985-95. [PMID: 8281950 DOI: 10.1111/j.1432-1033.1993.tb18457.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Recent studies have indicated that Escherichia coli possesses at least two iron-storage proteins, the haem-containing bacterioferritin and ferritin. The ferritin protein has been amplified 600-fold to 11-14% of total cell protein in a bfr mutant and purified to homogeneity with an overall yield of 13%. The cellular ferritin content remained relatively constant throughout the growth cycle and amplification was accompanied by a 2.5-fold increase in cellular iron content. The isolated ferritin contained 5-20 non-haem iron atoms/holomer and resembled the eukaryotic ferritins rather than the prokaryotic bacterioferritins in containing no haem. The 24 subunits of this ferritin (M(r) 19,400) assemble into a spherical protein shell (12 +/- 1 nm diameter, M(r) 465,000) which sequesters at least 2000 iron atoms in vitro to form an electron-dense iron core of 7.9 +/- 1 nm diameter. Electron-microscopic and Mössbauer spectroscopic studies with iron-loaded ferritin showed that the core can be either crystalline (ferrihydrite) or amorphous, depending on the absence or presence of phosphate, respectively. Mössbauer spectroscopy with intact E. coli revealed a novel-high spin Fe(II) component which is enhanced in bacteria amplified for ferritin but not in the parental strain. Western blotting showed that ferritin and bacterioferritin are immunologically distinct proteins. E. coli is thus an organism containing both a ferritin and a bacterioferritin and the relative roles of the two iron-storage proteins are discussed in this study.
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Affiliation(s)
- A J Hudson
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, England
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23
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Andrews SC, Smith JM, Hawkins C, Williams JM, Harrison PM, Guest JR. Overproduction, purification and characterization of the bacterioferritin of Escherichia coli and a C-terminally extended variant. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 213:329-38. [PMID: 8477705 DOI: 10.1111/j.1432-1033.1993.tb17766.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The bacterioferritin (BFR) of Escherichia coli is an iron-sequestering haemoprotein composed of 24 identical polypeptide chains forming an approximately spherical protein shell with a central iron-storage cavity. BFR and BFR-lambda, a variant with a 14-residue C-terminal extension, have been amplified (120-fold and 50-fold, respectively), purified by a new procedure and characterized. The overproduced BFR exhibited properties similar to those of natural BFR, but the iron content (25-75 non-haem Fe atoms/molecule) was 13-39-fold lower. Two major assembly states of BFR were detected, a 24-subunit protein (tetracosamer) and a novel haem-containing subunit dimer. BFR-lambda subunits assembled into tetracosamers having the same external-surface properties as BFR, presumably because their C-terminal extensions project into and occupy about 60% of the central cavity. As a result, BFR-lambda failed totake up iron under conditions that allowed incorporation into BFR in vitro. The haem content of BFR-lambda (1-2 haems/tetracosamer) was lower than that of BFR (3.5-10.5 haems/tetracosamer) and this, together with a difference in the visible spectra of the two haemoproteins, suggested that the C-terminal extensions in BFR-lambda perturb the haem-binding pockets. A subunit dimer form of BFR-lambda was not detected. A combination of Mössbauer spectroscopy and electron diffraction showed that the BFR loaded with iron in vitro has a ferrihydrite-like iron core, whereas the in-vivo loaded protein has an amorphous core.
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Affiliation(s)
- S C Andrews
- Krebs Institute of Biomolecular Research, Department of Molecular Biology & Biotechnology, University of Sheffield, England
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24
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Dedman DJ, Treffry A, Candy JM, Taylor GA, Morris CM, Bloxham CA, Perry RH, Edwardson JA, Harrison PM. Iron and aluminium in relation to brain ferritin in normal individuals and Alzheimer's-disease and chronic renal-dialysis patients. Biochem J 1992; 287 ( Pt 2):509-14. [PMID: 1445209 PMCID: PMC1133194 DOI: 10.1042/bj2870509] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Ferritin has been isolated and its subunit composition, iron and aluminium content determined in the cerebral cortex and cerebellum of normal individuals and in the cerebral cortex of Alzheimer's-disease and renal-dialysis patients. An e.l.i.s.a. for ferritin has been developed and the ferritin, non-haem iron and aluminium content of the parietal cortex were determined in normal individuals and Alzheimer's-disease patients. It was found that ferritin from the cerebral cortex and cerebellum of normal individuals had a high H-subunit content, similar to that of heart ferritin. The subunit composition of ferritin isolated from the cerebral cortex was not significantly altered in Alzheimer's-disease or renal-dialysis patients. Ferritin from the cerebral cortex of normal individuals had only approx. 1500 atoms of iron per molecule and the iron content of ferritin was not significantly changed in Alzheimer's-disease or renal-dialysis patients. Ferritin isolated from the cerebral cortex of normal, Alzheimer's-disease and renal-dialysis patients had less than 9 atoms of aluminium per molecule. The failure to find increased concentrations of aluminium associated with ferritin in dialysis patients, who had markedly increased concentrations of aluminium in the cerebral cortex, shows that aluminium does not accumulate in ferritin in vivo. This has important implications for the toxicity of aluminium, since it implies that cells are unable to detoxify aluminium by the same mechanism as that available for iron. Comparison of the concentrations of ferritin, aluminium and iron in the parietal cortex from normal and Alzheimer's-disease patients showed that, whereas the concentration of aluminium was not increased, both ferritin and iron were significantly increased in Alzheimer's disease.
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Affiliation(s)
- D J Dedman
- Department of Molecular Biology and Biotechnology, University of Sheffield, U.K
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25
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Goddard JG, Gower JD, Green CJ. A chelator is required for microsomal lipid peroxidation following reductive ferritin-iron mobilisation. FREE RADICAL RESEARCH COMMUNICATIONS 1992; 17:177-85. [PMID: 1459490 DOI: 10.3109/10715769209068164] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In the past, antioxidant and chelator studies have implicated a role for iron-dependent oxidative damage in tissues subjected to ischaemia followed by reperfusion. As ferritin is a major source of iron in non-muscular organs and therefore a potential source of the iron required for oxygen radical chemistry, we have determined conditions under which ferritin iron reduction leads to the formation of a pool of iron which is capable of catalysing lipid peroxidation. Under anaerobic conditions and in the presence of rat liver microsomes, flavin mononucleotide (FMN) catalysed the reduction of ferritin iron as shown by both continuous spectrophotometric measurements of tris ferrozine-Fe(II) complex formation and post-reaction Fe(II) determination. The presence of either ferrozine or citrate was not found to alter the time course or extent of ferritin reduction. In contrast, the addition of air to the reactants after a 20 min period of anaerobic reduction resulted in peroxidation of the microsome suspension (as determined with the 2-thiobarbituric acid test) only in the presence of a chelator such as citrate, ADP or nitrilotriacetic acid. These results support the concept that reduced ferritin iron can mediate oxidative damage during reperfusion of previously ischaemic tissues, provided that chelating agents such as citrate or ADP are present.
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Affiliation(s)
- J G Goddard
- Section of Surgical Research, Clinical Research Centre, Harrow, Middlesex, U.K
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26
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Yokoi K, Kimura M, Itokawa Y. Determination of nonheme iron using inductively coupled plasma-atomic emission spectrometry. Biol Trace Elem Res 1991; 31:265-79. [PMID: 1723616 DOI: 10.1007/bf02990196] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A technique for the rapid and accurate estimation of nonheme iron using inductively coupled plasma-atomic emission spectrometry is described. Yttrium was used as an internal standard. An external calibration method was used. The standards were prepared in a matrix composed of 2.5N HCl in 10% (w/v) trichloroacetic acid. The supernatant and coagulum fractions of liver nonheme iron were separated by the method of Drysdale and Ramsay with minor modification. The data determined by this procedure was compared and found to be agreement with data determined by the method of Hallgren. To evaluate the iron status of rats, hemoglobin and liver nonheme iron were determined. Hemoglobin and all of the nonheme iron fractions of the rats fed an iron-deficient diet were significantly lower than those of the rats fed an iron-sufficient diet. The blood content in the liver was estimated to be 80 microL/g from the blood iron concentration, and the difference between total and nonheme iron concentration in liver.
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Affiliation(s)
- K Yokoi
- Department of Hygiene, Faculty of Medicine, Kyoto University, Japan
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27
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FARAJI HABIBOLLAH, DECKER ERICA. Inhibition of Phosphatidylcholine Liposome Oxidation by Porcine Plasma. J Food Sci 1991. [DOI: 10.1111/j.1365-2621.1991.tb14636.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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28
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Carbonell T, Saiz MP, Mitjavila MT, Puig-Parellada P, Cambon-Gros C, Fernandez Y, Mitjavila S. Carrageenan-induced granuloma and iron status in rats with dietary polyunsaturated fatty acid deficiency. Br J Nutr 1991; 65:497-503. [PMID: 1878362 DOI: 10.1079/bjn19910108] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Sprague-Dawley rats were fed for 4 months on a control diet or a polyunsaturated-fatty-acid (PUFA)-deficient diet. The combined effects of iron overload (Fe dextran) or Fe deficiency (desferrioxamine) on carrageenan-induced granuloma were studied. PUFA deficiency induced changes in Fe metabolism, but no alterations in lipid peroxidation variables were observed. Inflammation implied an increase in lipid peroxidation, Fe storage and caeruloplasmin concentration, together with symptoms of anaemia. PUFA deficiency in inflamed rats gave rise to a lower inflammatory response (granuloma weight and prostaglandin E2 concentration) and ethane exhalation. Fe overload potentiated inflammatory and lipid peroxidation processes, whereas Fe deficiency decreased them.
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Affiliation(s)
- T Carbonell
- Departamento de Bioquimica y Fisiologia, Facultad de Biologia, Universidad de Barcelona, Spain
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29
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Bolann BJ, Ulvik RJ. On the limited ability of superoxide to release iron from ferritin. EUROPEAN JOURNAL OF BIOCHEMISTRY 1990; 193:899-904. [PMID: 2174370 DOI: 10.1111/j.1432-1033.1990.tb19415.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Reductive release of iron from ferritin may catalyze cytotoxic radical reactions like the Haber-Weiss reaction. The ability of .O2- to mobilize Fe(II) from ferritin was studied by using the xanthine/xanthine oxidase reaction, with and without superoxide dismutase, and with bathophenanthroline sulphonate as the chelator. Not more than one or two Fe(II)/ferritin molecules could be released by an .O2(-)-dependent mechanism, even after repeated exposures of ferritin to bursts of .O2-. The amount of releaseable iron depended on the size and the age of the iron core, but not on the iron content of the protein shell of ferritin which was manipulated by chelators and addition of FeCl3. The kinetic characteristics of the .O2(-)-mediated iron release indicated the presence of a small pool of readily available iron at the surface of the core. The very limited .O2(-)-dependent release of iron from ferritin is compatible with a protective role of ferritin against toxic iron-catalyzed reactions.
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Affiliation(s)
- B J Bolann
- Laboratory of Clinical Biochemistry, University of Bergen, Norway
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30
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Atkinson B, Blaker T, Tomlinson J, Dean R. Ferritin is a translationally regulated heat shock protein of avian reticulocytes. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(18)77281-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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31
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Dexter DT, Carayon A, Vidailhet M, Ruberg M, Agid F, Agid Y, Lees AJ, Wells FR, Jenner P, Marsden CD. Decreased ferritin levels in brain in Parkinson's disease. J Neurochem 1990; 55:16-20. [PMID: 2355217 DOI: 10.1111/j.1471-4159.1990.tb08814.x] [Citation(s) in RCA: 187] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Ferritin levels were measured in postmortem brain tissue from patients dying with Parkinson's disease [treated with L-3,4-dihydroxyphenylalanine (L-DOPA)] and from control patients. Ferritin levels were decreased in the substantia nigra, caudate-putamen, globus pallidus, cerebral cortex, and cerebellum when compared with age-matched control tissues. However, in CSF from L-DOPA-treated patients and in serum from L-DOPA-treated and untreated parkinsonian patients, ferritin levels were normal. Previous studies have suggested an increased total iron content in substantia nigra of parkinsonian brain. The failure of substantia nigra ferritin formation to be stimulated by increased iron levels suggests some defect in iron handling in this critical brain region in Parkinson's disease. The reason for decreased ferritin levels throughout the parkinsonian brain is not clear but does not seem to reflect a general system deficit in ferritin.
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Affiliation(s)
- D T Dexter
- Parkinson's Disease Society Research Centre, University Department of Neurology, London, England
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32
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Saiz MP, Martí MT, Mitjavila MT, Planas J. Sexual and age variations of organ iron content in Shaver chickens. Br Poult Sci 1990; 31:339-49. [PMID: 2372710 DOI: 10.1080/00071669008417264] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
1. Haematological values and iron content in liver, spleen, kidneys and intestine were determined in Shaver chickens of both sexes at 4, 8, 13 and 18 weeks and in females at 24 weeks (the beginning of the laying period). 2. The haematocrit decreased significantly in laying compared with non-laying females and the haemoglobin concentration was similar to that in the prelaying state. Plasma iron in laying females increased to four times the basal value at 13 weeks. 3. Females of 13 and 18 weeks (prelaying state) stored more iron than males at the same age. A simultaneous liver and spleen mobilisation of stored iron and increased intestinal iron accumulation took place in the laying process. The haematological variables examined were minimally altered. 4. The iron contents of both heart and kidneys were influenced by age and followed a linear trend, except that in the heart of females where a quadratic response was observed.
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Affiliation(s)
- M P Saiz
- Departamento de Bioquímica y Fisiología, Unidad de Fisiología, Faculdad de Biología, Universidad de Barcelona, Spain
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33
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Abstract
We have studied some hematological parameters and iron and ferritin iron contents in different organs of New Hampshire chickens at the ages of 4, 8, 13, and 18 wk for both sexes, as well as 24 wk for laying hens, in order to study the variations with age, the existence of sex differences, and the accommodations to laying. The hematocrit and hemoglobin levels did not show important variations, but plasma iron increased at laying. The iron and ferritin iron concentrations in liver and spleen increased more slowly during growth than the total iron and ferritin iron contents, and no significant decline was observed at laying. The iron concentration in the heart and pectoral muscle stayed constant throughout the period studied, and kidneys showed slight increase with age. However, the iron concentration in the intestine decreased from the proximal to the distal segments and also increased in the duodenum at laying. No differences caused by sex have been detected in the organs studied. The absence of differences caused by sex in the organ iron stores in favor of females, especially in liver, and the lack of influence of the laying process in iron stores could be a consequence of the low laying frequency of this strain.
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Affiliation(s)
- M T Marti
- Dpt. Bioquimica y Fisiologia, Facultad de Biologia, Universidad de Barcelona, Spain
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34
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Cambon-Gros C, Fernandez Y, Mitjavila MT, Carbonell T, Puig-Parellada P, Mitjavila S. Combined effect of a PUFA deficient diet and iron levels on lipid peroxidation induced by CCl4. FOOD ADDITIVES AND CONTAMINANTS 1990; 7 Suppl 1:S108-10. [PMID: 2262014 DOI: 10.1080/02652039009373860] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- C Cambon-Gros
- INSERM U-87, Université Paul Sabatier, Toulouse, France
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35
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Brady MC, Lilley KS, Treffry A, Harrison PM, Hider RC, Taylor PD. Release of iron from ferritin molecules and their iron-cores by 3-hydroxypyridinone chelators in vitro. J Inorg Biochem 1989; 35:9-22. [PMID: 2709002 DOI: 10.1016/0162-0134(89)84002-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Ferritin molecules contain 24 subunits forming a shell around an inorganic iron-core. Release of iron(III) from ferritin and its isolated iron-cores by a series of hydroxypyridinone chelators with high affinities for iron(III) has been compared. The results collectively suggest that the chelators act by penetrating the protein shell and interacting directly with the iron-core in ferritin. Iron(III) is probably removed bound to a single ligand, but once outside the protein shell, the trihydroxypyridinone iron(III) complex predominates. The order of effectiveness of a group of pyridinones found for iron removal from ferritin molecules in solution differs from that obtained with hepatocytes in culture or with whole animals, where membrane solubility and other factors may modulate the response.
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Affiliation(s)
- M C Brady
- Krebs Institute of Biomolecular Research, Department of Biochemistry, The University, Sheffield, United Kingdom
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36
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Bates CJ, Cowen TD, Tsuchiya H. Growth, ascorbic acid and iron contents of tissues of young guinea-pigs whose dams received high or low levels of dietary ascorbic acid or Fe during pregnancy and suckling. Br J Nutr 1988; 60:487-97. [PMID: 3219320 DOI: 10.1079/bjn19880121] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
1. Guinea-pig dams were fed on purified diets containing high (5 g/kg diet plus 1 g/l drinking water) or moderate (0.5 g/kg diet) levels of ascorbic acid, in combination with high (1 g/kg diet) or moderate (0.043 g/kg diet) levels of iron, during pregnancy and suckling. Their offsprings' diets contained 0.1 g ascorbic acid/kg and 0.04 g Fe/kg. 2. High ascorbic acid intake clearly enhanced both tissue ascorbate and Fe storage in the dams, and high Fe intake increased both the dams' and the pups' tissue Fe stores. 3. In the animals receiving high Fe intake, a co-existing high ascorbate intake by the dams reduced the growth rate of the offspring, but only during the early stages of development, not during the later stages of post-weaning growth. All the pups' tissue ascorbate levels fell after weaning, but those born of the dams receiving the high ascorbic acid diets did not fall to levels lower than those of the other pups. 4. Thus, although certain disadvantages to the offspring resulting from very-high ascorbic acid intake by pregnant guinea-pig dams were detected, these did not include permanently increased ascorbate requirements, and hence a progression to scurvy as the pups grew and matured.
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Affiliation(s)
- C J Bates
- MRC Dunn Nutritional Laboratory, Cambridge
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37
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Sánchez J, Casas M, Rama R. Effect of chronic ethanol administration on iron metabolism in the rat. Eur J Haematol Suppl 1988; 41:321-5. [PMID: 3197820 DOI: 10.1111/j.1600-0609.1988.tb00204.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
This study shows that the ingestion of ethanol provokes alterations in iron metabolism which may lead to iron overload. Impaired release of reticuloendothelial iron was shown by a decrease of the maximum red blood cell utilization when radioactive iron was supplied as colloidal iron. An impairment in the erythropoietic activity of ethanol-treated animals was also observed, as can be seen from the reduced plasma iron turnover and red blood cell utilization within 24 h of iron administration. A rise in marrow transit time was also observed. In ethanol-treated rats there was an increase in the amount of iron retained both in the liver and the spleen. This was observed in both sexes and also in the offspring from ethanol-treated mothers.
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Affiliation(s)
- J Sánchez
- Dept. Bioquímica y Fisiología, Universidad de Barcelona, Spain
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38
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Mitra A, Ray MK, Chatterjee GC. Role of iron in the enhancement by Agrobacterium tumefaciens infection in mice. Folia Microbiol (Praha) 1988; 33:255-60. [PMID: 3181831 DOI: 10.1007/bf02925617] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Microorganisms require iron for their growth and usually compete with their host for available iron from the system. Iron supplementation to host causes an increase of available iron both to host and to potential microbial invaders and favours the latter more than the former as the bacteria release siderophores which are responsible for iron transport mechanism. In view of this observation a study was done to deal with the distribution of storage and injected iron given as an overload within a physiological pool, taking mice as the host, with a correlation to its utilization by Agrobacterium tumefaciens and with bacterial growth and multiplication. The results obtained help in understanding the host--parasite relationships, regarding bacterial virulence and infection and the growth-promoting effect of iron, as iron promoted the development and progression of serum-exposed A. tumefaciens in mice.
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Affiliation(s)
- A Mitra
- Department of Biochemistry, University of Calcutta, India
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39
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Nomura Y, Kobayashi K, Tanaka K. A long term survey of plasma and tissue ferritin in mice fed on iron deficient diets. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. A, COMPARATIVE PHYSIOLOGY 1988; 91:259-62. [PMID: 2904340 DOI: 10.1016/0300-9629(88)90414-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
1. Changes in plasma and tissue ferritin concentrations were surveyed in mice fed on iron deficient diets (Fe, 2.4 micrograms/g) from the age of 8 to 30 weeks by an enzyme-immunoassay for mouse ferritin. Values were compared with those in mice on control diets (Fe, 110 micrograms/g) and mice with blood loss. 2. In mice on iron deficient diets, while plasma ferritin remained at normal level, ferritin in the spleen and kidney decreased, but that in the liver increased as much as twice of that in the control. 3. Mice with blood loss revealed a drastic reduction of ferritin in every tissue and plasma examined.
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Affiliation(s)
- Y Nomura
- Yamaguchi Prefectural Research Institute of Health, Japan
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Andrews SC, Brady MC, Treffry A, Williams JM, Mann S, Cleton MI, de Bruijn W, Harrison PM. Studies on haemosiderin and ferritin from iron-loaded rat liver. BIOLOGY OF METALS 1988; 1:33-42. [PMID: 3152870 DOI: 10.1007/bf01128015] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Haemosiderin has been isolated from siderosomes and ferritin from the cytosol of livers of rats iron-loaded by intraperitoneal injections of iron-dextran. Siderosomal haermosiderin, like ferritin, was shown by electron diffraction to contain iron mainly in the form of small particles of ferrihydrite (5Fe2O3.9H2O), with average particle diameter of 5.36 +/- 1.31 nm (SD), less than that of ferritin iron-cores (6.14 +/- 1.18 nm). Mössbauer spectra of both iron-storage complexes are also similar, except that the blocking temperature, TB, for haemosiderin (23 K) is lower than that of ferritin (35 K). These values are consistent with their differences in particle volumes assuming identical magnetic anisotropy constants. Measurements of P/Fe ratios by electron probe microanalysis showed the presence of phosphorus in rat liver haemosiderin, but much of it was lost on extensive dialysis. The presence of peptides reacting with anti-ferritin antisera and the similarities in the structures of their iron components are consistent with the view that rat liver haemosiderin arises by degradation of ferritin polypeptides, but its peptide pattern is different from that found in human beta-thalassaemia haemosiderin. The blocking temperature, 35 K, for rat liver ferritin is near to that reported, 40 K, for human beta-thalassaemia spleen ferritin. However, the haemosiderin isolated from this tissue, in contrast to that from rat liver, had a TB higher than that of ferritin. The iron availability of haemosiderins from rat liver and human beta-thalassaemic spleen to a hydroxypyridinone chelator also differed. That from rat liver was equal to or greater, and that from human spleen was markedly less, than the iron availability from either of the associated ferritins, which were equivalent. The differences in properties of the two types of haemosiderin may reflect their origins from primary or secondary iron overload and differences in the duration of the overload.
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Affiliation(s)
- S C Andrews
- Department of Biochemistry, University of Sheffield, UK
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41
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Mann S, Williams JM, Treffry A, Harrison PM. Reconstituted and native iron-cores of bacterioferritin and ferritin. J Mol Biol 1987; 198:405-16. [PMID: 3123700 DOI: 10.1016/0022-2836(87)90290-7] [Citation(s) in RCA: 102] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The structural and magnetic properties of the iron-cores of reconstituted horse spleen ferritin and Azotobacter vinelandii bacterioferritin have been investigated by high-resolution transmission electron microscopy, electron diffraction and Mossbauer spectroscopy. The structural properties of native horse spleen ferritin, native Az. vinelandii, and native and reconstituted Pseudomonas aeruginosa bacterioferritins have also been determined. Reconstitution in the absence of inorganic phosphate at pH 7.0 showed sigmoidal behaviour in each protein but was approximately 30% faster in initial rate for the Az. vinelandii protein when compared with horse spleen apoferritin. The presence of Zn2+ reduced the initial rate of Fe(II) oxidation in Az. vinelandii to 22% of the control rate. The iron-cores of the reconstituted bacterioferritins adopt defect ferrihydrite structures and are more highly ordered than their native counterparts, which are both amorphous. However, the blocking temperature for reconstituted Az. vinelandii (22.2 K) is almost identical to that for the native protein (20 K). Particle size measurements indicate that the reconstituted Az. vinelandii cores are smaller in median diameter than the native cores and this reduction in particle volume (V) offsets the increased magnetocrystalline contribution to the magnetic anisotropy constant (K) in such a way that the magnetic anisotropy barrier (KV), and hence the blocking temperature, is similar for both proteins. Reconstituted horse spleen ferritin exhibits a similar blocking temperature (38 K) to that determined for the native protein, although it is structurally more disordered. The possibility of introducing structural and compositional modifications in both horse ferritin and bacterioferritins by in-vitro reconstitution suggests that these proteins do not function primarily as a crystallochemical-specific interface for core development in vivo.
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Affiliation(s)
- S Mann
- School of Chemistry, University of Bath, U.K
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42
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Treffry A, Harrison PM, Cleton MI, de Bruijn WC, Mann S. A note on the composition and properties of ferritin iron cores. J Inorg Biochem 1987; 31:1-6. [PMID: 3320272 DOI: 10.1016/0162-0134(87)85001-8] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In ferritins and bacterioferritins iron is stored as an inorganic complex within a protein shell. The composition and properties of this complex are surprisingly variable. Factors that may lead to such variability are discussed.
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Affiliation(s)
- A Treffry
- Department of Biochemistry, The University, Sheffield, U.K
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43
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Ishimatsu T, Nakayama I. Localization of ferritin in human liver diseases studied by immuno-histochemical and immuno-electron microscopic procedures. ACTA PATHOLOGICA JAPONICA 1987; 37:1207-21. [PMID: 3314330 DOI: 10.1111/j.1440-1827.1987.tb00455.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Localization of ferritin using a pre-embedding diffusion technique and an indirect localization sequence has been made in 34 cases of human liver under normal and several pathological conditions. With light microscopic observation, positive immuno-staining for ferritin was demonstrated as diffuse deposits in the hepatocytes and Kupffer cells. Intensity of the positive immuno-staining for ferritin in these cells appeared to roughly coincide with serum ferritin levels of each patient, but showed no disease specificity, although hepatoma cells contained weak deposits or were negative from immuno-staining for ferritin. With electron microscopic studies, intracellular antigen was well preserved in the hepatocytes and Kupffer cells in most cases with the positive immuno-staining for ferritin being observed in cytosol and a few cisternae of rough endoplasmic reticulum. Content of the positive immuno-staining for ferritin differed considerably from one case to another and one cell to another even in the same case. There was no immuno-staining for ferritin in hemosiderin pigment, lysosome, most of rough endoplasmic reticulum, Golgi complexes, and nucleus in both cells.
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Affiliation(s)
- T Ishimatsu
- First Department of Pathology, Medical College of Oita, Japan
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44
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Andrews SC, Treffry A, Harrison PM. Siderosomal ferritin. The missing link between ferritin and haemosiderin? Biochem J 1987; 245:439-46. [PMID: 3663170 PMCID: PMC1148141 DOI: 10.1042/bj2450439] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A minor electrophoretically fast component was found in ferritin from iron-loaded rat liver in addition to a major electrophoretically slow ferritin similar to that observed in control rats. The electrophoretically fast ferritin showed immunological identity with the slow component, but on electrophoresis in SDS it gave a peptide of 17.3 kDa, in contrast with the electrophoretically slow ferritin, which gave a major band corresponding to the L-subunit (20.7 kDa). Thus the electrophoretically fast ferritin resembles that reported by Massover [(1985) Biochim. Biophys. Acta 829, 377-386] in livers of mice with short-term parenteral iron overload. The electrophoretically fast ferritin had a lower iron content (2000 Fe atoms/molecule) than the electrophoretically slow ferritin (3000 Fe atoms/molecule). Removal and re-incorporation of iron was possible without effect on the electrophoretic mobility of either ferritin species. On subcellular fractionation the electrophoretically fast ferritin was enriched in pellet fractions and was the sole soluble ferritin isolated from iron-laden secondary lysosomes (siderosomes). The amount and relative proportion of the electrophoretically fast species increased with iron loading. Haemosiderin isolated from siderosomes was found to contain a peptide reactive to anti-ferritin serum and corresponding to the 17.3 kDa peptide of the electrophoretically fast ferritin species. Unlike the electrophoretically slow ferritin, the electrophoretically fast ferritin did not become significantly radioactive in a 1 h biosynthetic labelling experiment. We conclude that the minor ferritin is not, as has been suggested for mouse liver ferritin, 'a completely new species of smaller holoferritin that represents a shift in the ferritin phenotype' in response to siderosis, but a precursor of haemosiderin, in agreement with the proposal by Richter [(1984) Lab. Invest. 50, 26-35] concerning siderosomal ferritin.
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Affiliation(s)
- S C Andrews
- Department of Biochemistry, University of Sheffield, U.K
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45
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St Pierre TG, Dickson DP, Kirkwood JK, Ward RJ, Peters TJ. A Mössbauer spectroscopic study of the form of iron in iron overload. BIOCHIMICA ET BIOPHYSICA ACTA 1987; 924:447-51. [PMID: 3593763 DOI: 10.1016/0304-4165(87)90159-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
There are major differences in the temperature dependence of the Mössbauer spectra of ferritin and haemosiderin extracted from the organs of humans suffering from transfusional iron overload. Iron overload can also occur in animal systems as a result of artificial treatments or dietary factors. None of the animal systems which were investigated in the present study showed evidence in their Mössbauer spectra for the presence of the haemosiderin found in transfusional iron overload in humans. This suggests that the haemosiderin which occurs in the case of human transfusional iron overload may be specific to that situation.
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Simon M, MacPhail P, Bothwell T, Lyons G, Baynes R, Torrance J. The fate of intravenously administered hepatic ferritin in normal, phenylhydrazine-treated and scorbutic guinea-pigs. Br J Haematol 1987; 65:239-43. [PMID: 3828233 DOI: 10.1111/j.1365-2141.1987.tb02272.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
When highly purified hepatic 59Fe-ferritin was injected intravenously into normal guinea-pigs more than half of it was taken up by red cell precursors and the iron was used for haem formation. This was studied in more detail in animals in which a reticulocytosis had been induced either by phenylhydrazine or by repeated venescetions. 55% of the injected ferritin iron was found in reticulocytes at 1 h. Experiments using ferritin doubly labelled with 59Fe and 125I indicated that the whole molecule was taken up, with two-thirds of the radioactivity being associated with the membrane at 1 h and one third being already within the cell. There was a progressive loss of 125I activity over the ensuing hours, while most of the 59Fe was slowly internalized and incorporated into haem between 1 and 24 h. In contrast, 90% of the activity taken up by red cell precursors from 59Fe-transferrin was present as haem at all times. The liver and spleen were the two other major sites of 59Fe-ferritin uptake in phenylhydrazine treated animals. While there was an early uptake of 59Fe into haem in these organs, some redistribution occurred with time, since most of the 59Fe was in a non-haem fraction by 24 h. In a final experiment the distribution and fate of 59Fe-ferritin was studied in scorbutic animals treated with phenylhydrazine. The findings were similar to those in normals similarly treated, which suggests that ferritin iron was being effectively mobilized for haem formation despite the ascorbic acid depletion.
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Diez JM, Agapito MT, Recio JM. Serum iron, serum ferritin and tissue ferritin during development in ducks. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. A, COMPARATIVE PHYSIOLOGY 1987; 86:389-93. [PMID: 2881681 DOI: 10.1016/0300-9629(87)90348-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Serum ferritin and tissue ferritin from kidney, heart, small intestine, spleen and liver from ducks during development from 16 to 112 days of age were measured by radioimmunoassay using rabbit anti-duck liver ferritin antibodies and goat second antibody. Serum iron concentration and tissue ferritin iron content are given. Serum ferritin concentration, tissue ferritin and ferritin iron content increase gradually during development. The decrease in all these parameters at 8 weeks of age might be due to molting.
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48
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Longueville A, Crichton RR. An animal model of iron overload and its application to study hepatic ferritin iron mobilization by chelators. Biochem Pharmacol 1986; 35:3669-78. [PMID: 3778498 DOI: 10.1016/0006-2952(86)90650-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Administration of 3,5,5-trimethylhexanoyl ferrocene in the diet of male Wistar rats results in a substantial increase in hepatic ferritin protein (greater than 2-fold) and of ferritin iron (4-8-fold). The iron-loading in liver, under the conditions used, appears to be essentially in parenchymal cells rather than in reticulo-endothelial cells. It is suggested that the model represents a useful system for the study of the potential efficacy of new iron chelators for the mobilization of hepatic storage iron. The ability of desferal (DFO) and of a new siderophore, desferrithiocin (DFT), to mobilize hepatic ferritin iron is observed in this model of iron overload. Desferrithiocin stimulates ferritin iron mobilization, when administered either by gavage or by intraperitoneal injection, whereas desferal is active intraperitoneally but inactive orally. Our studies lead to the conclusion that DFT merits further examinations, for its activity as an orally active iron chelator.
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Cukrová V, Hrkal Z, Koprivová H, Neuwirt J. Identification of leukemia cell-derived inhibitory activity (LIA) in conditioned media from human myeloid leukemic cell line ML-2. BLUT 1986; 52:51-8. [PMID: 3484646 DOI: 10.1007/bf00320142] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Conditioned media from the human myeloid leukemic cell line ML-2 contain a factor that inhibits the entry of normal CFU-GM into S phase of mitotic cycle as measured by the 3H-TdR suicide technique. This factor was detected in conditioned media prepared by incubating 5 X 10(6) ML-2 cells/ml or 1 X 10(6) ML-2 cells/ml in serum-free RPMI for 5 or 24 hours respectively, and was isolated by ultrafiltration through an XM 300 Diaflo membrane followed by chromatography on Sepharose 6 B. Ferritin, prepared from human placenta, had the same inhibitory effect on CFU-GM. Antibodies against human placental ferritin completely inactivated the inhibitory effect of both human placental ferritin and the factor released from ML-2 cells. The inhibitory activity produced by the cell-line ML-2 was considered as LIA (leukemia cell-derived inhibitory activity) earlier found in HL-60 cell line and AML and CML cells.
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Abstract
Dynamic studies of iron metabolism in brain are generally unavailable despite the fact that a number of neurologic conditions are associated with excessive accumulation of iron in central nervous tissue. Cortical non-neuronal (glial) cultures were prepared from fetal mouse brain. After 13 days the cultures were exposed to radiolabeled iron. Brisk and linear total iron uptake and ferritin iron uptake occurred over 4 hours. When methylamine or ammonium chloride was added, (both known inhibitors of transferrin iron release because of their lysosomotropic properties), total iron uptake was diminished. Further studies indicated that methylamine inhibits glial cell ferritin iron incorporation. Glial cell iron transport is similar to previously reported neuronal cell iron transport (1) but glial cell iron uptake proceeds at a faster rate and is more susceptible to the inhibition of certain lysosomotropic agents. The data reinforces the likelihood that iron uptake by nervous tissues is transferrin-mediated.
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