Aluminum (III) induces alterations on the physical state of the erythrocytic membrane: an ESR evaluation.
The action of aluminum [Al(III)] as Al(acac)3 on erythrocytes causes biophysical effects such as osmotic fragility and echino-acanthocytes formation. In this paper, we present these effects in terms of variation of membrane fluidity, together with findings regarding conformational modifications of membrane proteins consequent to Al(III) exposure, as well as the effects on the mobility of the membrane protein bound sialic acid. To this end, we utilized ESR measurements of rabbits and humans erythrocytic ghosts after probing or labeling with suitable stable radicals used as spin probes or labels. Our results show that the lipophilic, hydrolytically stable toxicant Al(acac)3 causes a remarkable reduction of membrane fluidity in rabbit erythrocytes, an appreciable structural compacting effect on cytoskeletal and transmembrane proteins, as well as a reduction of rotational mobility of cell-surface sialic acid of human erythrocytes.
Zatta
P
P
Dipartimento di Biologia, Centro CNR per lo Studio delle Metalloproteine, Padova, Italy.
Zambenedetti
P
P
Toffoletti
A
A
Corvaja
C
C
Corain
B
B
D000535:Aluminum / Q000737:chemistry / Q000633:toxicity*; D000818:Animals; D055592:Biophysical Phenomena; D001703:Biophysics; D003598:Cytoskeletal Proteins / Q000737:chemistry; D004578:Electron Spin Resonance Spectroscopy; D004910:Erythrocyte Membrane / Q000737:chemistry / Q000187:drug effects*; D006801:Humans; D066298:In Vitro Techniques; D008560:Membrane Fluidity / Q000187:drug effects; D008565:Membrane Proteins / Q000737:chemistry; D009942:Organometallic Compounds / Q000737:chemistry / Q000633:toxicity*; D010422:Pentanones / Q000737:chemistry / Q000633:toxicity*; D011817:Rabbits; D012794:Sialic Acids / Q000737:chemistry; D013113:Spin Labels
D003598:Cytoskeletal Proteins; D008565:Membrane Proteins; D009942:Organometallic Compounds; D010422:Pentanones; D012794:Sialic Acids; D013113:Spin Labels; C058508:tris(acetylacetonate) aluminum(III); D000535:Aluminum