Consulta: creatorFacets:"ARREDONDO,MIGUEL"
Registros recuperados: 5
Data/hora: 12/06/2024 02:31:01

Inhibition of iron and copper uptake by iron, copper and zinc
Provedor de dados: 48
Autores: ARREDONDO,MIGUEL; MARTÍNEZ,RONNY; NÚÑEZ,MARCO T; RUZ,MANUEL; OLIVARES,MANUEL.
Interactions of micronutrients can affect absorption and bioavailability of other nutrients by a number of mechanisms. In aqueous solutions, and at higher uptake levels, competition between elements with similar chemical characteristics and uptake process can take place. The consequences of these interactions may depend on the relative concentrations of the nutrients. In this work, we measure the effects of increasing concentrations of iron, zinc, and copper on iron and copper uptake in Caco-2 cells. Intracellular Fe or Cu levels were affected by incubating with increased concentrations of metals. However, when the cells already had different intracellular metal concentration, the uptake of Fe or Cu was nor affected. In competition studies, we showed that...
Tipo: Journal article
Palavras-chave: Competition; Interaction; Metals; Uptake.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602006000100011

Antioxidant responses of cortex neurons to iron loading
Provedor de dados: 48
Autores: AGUIRRE,PABLA; MENA,NATALIA; TAPIA,VICTORIA; ROJAS,ALEJANDRO; ARREDONDO,MIGUEL; NÚÑEZ,MARCO TULIO.
Brain cells have a highly active oxidative metabolism, yet they contain only low to moderate superoxide dismutase and catalase activities. Thus, their antioxidant defenses rely mainly on cellular reduced glutathione levels. In this work, in cortical neurons we characterized viability and changes in reduced and oxidized glutathione levels in response to a protocol of iron accumulation. We found that massive death occurred after 2 days in culture with 10 mM Fe. Surviving cells developed an adaptative response that included increased synthesis of GSH and the maintenance of a glutathione-based reduction potential. These results highlight the fundamental role of glutathione homeostasis in the antioxidant response and provide novel insights into the adaptative...
Tipo: Journal article
Palavras-chave: Glutathione; Iron; Redox response; Cortical neurons; Cell death.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602006000100012

The cellular mechanisms of body iron homeostasis
Provedor de dados: 48
Autores: NUÑEZ,MARCO T; GARATE,MARCO A; ARREDONDO,MIGUEL; TAPlA,VICTORIA; MUÑOZ,PATRICIA.
Cells tightly regulate iron levels through the activity of iron regulatory proteins (IRPs) that bind to RNA motifs called iron responsive elements (IREs). When cells become iron-depleted, IRPs bind to IREs present in the mRNAs of ferritin and the transferrin receptor, resulting in diminished translation of the ferritin mRNA and increased translation of the transferrin receptor mRNA. Similarly, body iron homeostasis is maintained through the control of intestinal iron absorption. Intestinal epithelia cells sense body iron through the basolateral endocytosis of plasma transferrin. Transterrin endocytosis results in enterocytes whose iron content will depend on the iron saturation of plasma transferrin. Cell iron levels, in turn, inversely correlate with...
Tipo: Journal article
Palavras-chave: Metal ions; Intestinal absorption; Ferritin; Transferrin; Homeostasis.
Ano: 2000
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602000000200013

Heme oxygenase 1 overexpression increases iron fluxes in Caco-2 cells
Provedor de dados: 48
Autores: MENDIBURO,MARÍA JOSE; FLORES,SEBASTIÁN; PIZARRO,FERNANDO; ARREDONDO,MIGUEL.
Heme oxygenase-1 is a microsomal enzyme that, when induced by stress, protects the cells from oxidative injury. Heme oxygenase-1 participates in the cleavage of the heme ring producing biliverdin, CO and ferrous Fe. The released Fe becomes part of intracellular Fe pool and can be stored in ferritin or released by an iron exporter. The mechanism by which heme enters cells is not completely understood, although it had been suggested that it might be internalized by an endocytosis process. In this study, we expressed a full-length Heme oxygenase-1 cDNA in Caco-2 cells and measured intracellular iron content, heme-iron uptake and transport and immunolocalization of heme oxygenase-1 in these cells. We found that heme oxygenase-1 expressing cells showed...
Tipo: Journal article
Palavras-chave: Iron; Heme; Heme oxygenase; Caco-2 cells.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602006000100023

Understanding copper homeostasis in humans and copper effects on health
Provedor de dados: 48
Autores: ARAYA,MAGDALENA; PIZARRO,FERNANDO; OLIVARES,MANUEL; ARREDONDO,MIGUEL; GONZÁLEZ,MAURICIO; MÉNDEZ,MARCO.
Tipo: Journal article
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602006000100020