Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P02794 (ferritin)
 17,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The ferritin IRE, a highly conserved (96-99% in vertebrates) mRNA translation regulatory element in animal mRNA, was studied by molecular modeling (using MC-SYM and DOCKING) and by NMR spectroscopy. Cobalt(III) hexammine was used to model hydrated Mg2+. IRE isoforms in other mRNAs regulate mRNA translation or stability; all IREs bind IRPs (iron regulatory proteins). A G.C base pair, conserved in ferritin IREs, spans an internal loop/bulge in the middle of an A-helix and, combined with a dynamic G.U base pair, formed a pocket suitable for Co(III) hexammine binding. On the basis of the effects of Co(III) hexammine on the 1H NMR spectrum and results of automatic docking into the IRE model, the IRE bound Co(III) hexammine at the pocket in the major groove; Mg2+ may bind to the IRE at the same site on the basis of an analogy to Co(III) hexammine and on the Mg2+ inhibition of Cu-(phen)2 cleavage at the site. Distortion of the IRE helix by the internal loop/bulge near a conserved unpaired C required for IRP binding and adjacent to an IRP cross-linking site suggests a role for the pocket in ferritin IRE/IRP interactions.
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PMID:Iron regulatory element and internal loop/bulge structure for ferritin mRNA studied by cobalt(III) hexammine binding, molecular modeling, and NMR spectroscopy. 948 20

Imbalances between mineral intakes and recommended amounts have been observed in different groups of elderly subjects. Nevertheless, assessment of the status of magnesium and trace elements in the elderly is difficult, even for iron because infection and inflammation increases ferritin. Mineral bioavailability may change due to ageing. Therefore, formulation of mineral recommendations is complex and individual recommendations are sometimes necessary. A number of surveys show magnesium, zinc, selenium and chromium intakes by old persons to be lower than the corresponding reference nutrient intakes. Contrarily, intakes of iron are generally adequate or higher than recommended, and it has been suggested that increased storage of iron in the elderly may be related with the development of age-related diseases through the increase in oxidative stress. Low iron status together with iron excess may be common in an elderly population. The same applies for zinc. Magnesium and selenium deficiencies among the elderly are also well documented, especially among the institutionalised and people with pathologies. Chromium deficiency is associated with type II diabetes mellitus. Recommended iron intake is lower for elderly women compared to young, because menstruation ceases after menopause, but in old men, it is similar to that of young men. Dietary Reference Values for the rest of the elements are similar to those of adults, although several suggestions have been made about the quantities. This review examines various aspects of the changes in mineral bioavailability due to ageing, of data published on mineral intakes and status, and finally the dietary recommendations for this vulnerable population group.
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PMID:Magnesium and trace elements in the elderly: intake, status and recommendations. 1216 71

Streptococcus suis (S. suis) is an important pathogen in pigs and has to overcome strict iron limitations in its host environment. Here, we studied iron-restricted growth of a highly virulent S. suis strain in vitro at aerobic and CO2-enriched growth conditions. At both conditions, depleting of iron in the culture medium with nitrilotriacetic acid (NTA) resulted in decreased growth rates and down regulation of several proteins. Sensitivity to NTA was significantly higher at aerobic versus CO2-enriched conditions. Growth could not be restored by addition of host iron sources such as ferritin, hemin, hemoglobin, lactoferrin or transferrin. Accordingly, S. suis was not able to produce detectable amounts of siderophores. On the other hand, growth at iron-restricted conditions was fully restored by addition of Mn2+ (at aerobic and CO2-enriched conditions) or Mg2+ (only at CO2-enriched conditions). In conclusion our results suggest that, unlike many other bacteria, S. suis adapts to iron restricted conditions by a change in its metabolism in order to replace Fe2+ by Mn2+ or Mg2+ rather than by expressing specific iron uptake systems.
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PMID:Response of Streptococcus suis to iron-restricted growth conditions at high and low oxygen availability. 1529 52

Aminoacetone (AA) is a threonine metabolite accumulated in threoninemia, cri-du-chat, and diabetes, where it contributes toward the formation of cytotoxic and genotoxic methylglyoxal (MG). Oxyradicals yielded from iron-catalyzed AA aerobic oxidation to MG are shown here to promote Ca2+ -mediated mitochondrial membrane permeabilization in an AA dose-dependent way. The inhibitory effect of added EGTA, cyclosporin A, Mg2+, and DTT observed in this study suggests the formation of transition pores in the inner mitochondrial membrane by AA, associated with thiol protein aggregation. That the mitochondrial iron pool plays a coadjutant role in the transition of mitochondrial permeability is indicated by the dramatic inhibitory effect of added o-phenanthroline. Iron released from ferritin by AA oxidation products--superoxide anion and AA enolyl radicals--is shown to act as an alternative source of ferrous iron, intensifying the mitochondrial damage. These findings may contribute to clarify the role of accumulated AA and iron overload in the mitochondrial oxidative damage reportedly occurring in diabetes mellitus.
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PMID:Aminoacetone induces iron-mediated oxidative damage to isolated rat liver mitochondria. 1536 28


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