title: Changes in red blood cells membrane protein composition during hemodialysis procedure.
abstract: Our aim was to evaluate the influence of the hemodialysis (HD) procedure in red blood cells (RBC) membrane protein composition. We evaluated hematological data (RBC count, hemoglobin concentration, and hematimetric indices) and RBC membrane protein composition (linear and exponential gradient polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate [SDS-PAGE] followed by densitometry analysis of RBC membrane proteins) before and immediately after the HD procedure in 20 patients (10 responders and 10 non-responders to recombinant human erythropoietin therapy [rhEPO]) and 26 healthy controls. Before HD, patients presented anaemia and significant changes in membrane protein composition, namely, a statistically significant reduction in spectrin associated with a significant increase in bands 6, as well as an altered membrane protein interaction (protein 4.1/spectrin, protein 4.1/band 3, protein 4.2/band 3 and spectrin/band 3). After HD, we found that patients showed a statistically significant increase in RBC count and hemoglobin, a further and statistically significant decrease in spectrin, an increase in band 3, and an altered spectrin/band 3 ratio. When comparing responders and non-responders patients after HD, we found that the non-responders presented a trend to a higher reduction in spectrin. Our data suggest that HD procedure seems to contribute to a reduction in spectrin, which is normally associated with a reduction in RBC deformability, being that reduction in spectrin is higher in non-responder patients.
authors.affiliation: Faculdade de Farmácia, Serviço de Bioquímica, Universidade do Porto, Porto, Portugal. elisio_ costa@hotmail.com
authors.forename: Elísio
authors.initials: E
authors.lastname: Costa
authors.forename: Susana
authors.initials: S
authors.lastname: Rocha
authors.forename: Petronila
authors.initials: P
authors.lastname: Rocha-Pereira
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Castro
authors.forename: Vasco
authors.initials: V
authors.lastname: Miranda
authors.forename: Maria do Sameiro
authors.initials: Mdo S
authors.lastname: Faria
authors.forename: Alfredo
authors.initials: A
authors.lastname: Loureiro
authors.forename: Alexandre
authors.initials: A
authors.lastname: Quintanilha
authors.forename: Luís
authors.initials: L
authors.lastname: Belo
authors.forename: Alice
authors.initials: A
authors.lastname: Santos-Silva
mesh_terms: D000328:Adult; D000368:Aged; D000740:Anemia / Q000517:prevention & control; D016022:Case-Control Studies; D004906:Erythrocyte Count; D004910:Erythrocyte Membrane / Q000378:metabolism*; D004921:Erythropoietin / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D008875:Middle Aged; D011994:Recombinant Proteins; D006435:Renal Dialysis; D013049:Spectrin / Q000378:metabolism*
chemical_list: D008565:Membrane Proteins; D011994:Recombinant Proteins; D004921:Erythropoietin; D013049:Spectrin