title: Pentavalent antimony uptake pathway through erythrocyte membranes: molecular and atomic fluorescence approaches.
abstract: Previous studies by our group have shown that Sb(V) is able to enter red blood cells in a dynamic process and is reduced to Sb(III) by glutathione. The present study aims to investigate a possible entry pathway for Sb(V) through the erythrocyte membrane. Applying fluorescence spectroscopy studies with Laurdan and diphenylhexatriene (DPH) probes, it was found that there was no interaction between Sb(V) and membrane lipids. By comparing the Sb(V) entry percentages through lipid vesicles and sealed erythrocyte membranes, it was found that Sb(V) required protein channels to pass through the membrane. The competitive inhibition results using HCO3 (-) and Cl(-) showed that the Sb(V) uptake rate through the membrane fell approximately 50-70 % until full inhibition was reached, which was possibly due to the inhibition of the anion exchanger 1 (AE1) channel. Finally, the fluorescence measurements with the 5-iodoacetamidofluorescein (5-IAF) probe showed that Sb(V) interacted with membrane protein SH groups during this process.
authors.affiliation: Institute of Chemistry, Pontificia Universidad Católica de Valparaíso, Avenida Universidad #330, Campus Curauma, Valparaíso, Chile.|Institute of Biology, Pontificia Universidad Católica de Valparaíso, Avenida Universidad #330, Curauma, Valparaíso, Chile.
authors.forename: Camila
authors.initials: C
authors.lastname: Barrera
authors.affiliation: Institute of Chemistry, Pontificia Universidad Católica de Valparaíso, Avenida Universidad #330, Campus Curauma, Valparaíso, Chile.
authors.forename: Silvana
authors.initials: S
authors.lastname: López
authors.affiliation: Institute of Chemistry, Pontificia Universidad Católica de Valparaíso, Avenida Universidad #330, Campus Curauma, Valparaíso, Chile.
authors.forename: Luis
authors.initials: L
authors.lastname: Aguilar
authors.affiliation: Institute of Biology, Pontificia Universidad Católica de Valparaíso, Avenida Universidad #330, Curauma, Valparaíso, Chile.
authors.forename: Luis
authors.initials: L
authors.lastname: Mercado
authors.affiliation: Institute of Chemistry, Pontificia Universidad Católica de Valparaíso, Avenida Universidad #330, Campus Curauma, Valparaíso, Chile.
authors.forename: Manuel
authors.initials: M
authors.lastname: Bravo
authors.affiliation: Institute of Chemistry, Pontificia Universidad Católica de Valparaíso, Avenida Universidad #330, Campus Curauma, Valparaíso, Chile. waldo.quiroz@ucv.cl.
authors.forename: Waldo
authors.initials: W
authors.lastname: Quiroz
mesh_terms: D000965:Antimony / Q000378:metabolism*; D004910:Erythrocyte Membrane / Q000378:metabolism*; D006801:Humans; D012015:Reference Standards; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013438:Sulfhydryl Compounds / Q000737:chemistry
chemical_list: D013438:Sulfhydryl Compounds; D000965:Antimony
keywords: AE1; Antimony; Erythrocytes; Membrane; Uptake pathway