Increased red cell calcium, decreased calcium adenosine triphosphatase, and altered membrane proteins during fava bean hemolysis in glucose-6-phosphate dehydrogenase-deficient (Mediterranean variant) individuals.
RBCs from four glucose-6-phosphate dehydrogenase (G6PD)-deficient (Mediterranean variant) subjects were studied during fava bean hemolysis. In the density-fractionated RBC calcium level, Ca2+-ATPase activity, reduced glutathione level, and ghost protein pattern were studied. In the bottom fraction, containing most heavily damaged RBCs, calcium level ranged from 143 to 244 mumol/L RBCs (healthy G6PD-deficient controls: 17 +/- 5 mumol/L RBCs). The Ca2+-ATPase activity ranged from 0.87 to 1.84 mumol ATP consumed/g Hb/min (healthy G6PD-deficient controls: 2.27 +/- 0.4). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of ghosts showed: (1) the presence of high mol wt aggregates (in three cases they were reduced by dithioerythritol; in one case, only partial reduction was possible); (2) the presence of multiple, scattered new bands; and (3) the reduction of band 3. Oxidant-mediated damage to active calcium extrusion, hypothetically associated with increased calcium permeability, may explain the large increase in calcium levels. They, in turn, could activate calcium-dependent protease activity, giving rise to the profound changes in the ghost protein pattern.
Turrini
F
F
Naitana
A
A
Mannuzzu
L
L
Pescarmona
G
G
Arese
P
P
D000293:Adolescent; D000328:Adult; D000368:Aged; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D002469:Cell Separation; D002648:Child; D004226:Dithioerythritol; D004591:Electrophoresis, Polyacrylamide Gel; D004912:Erythrocytes / Q000378:metabolism*; D005236:Favism / Q000097:blood*; D005260:Female; D005978:Glutathione / Q000378:metabolism; D006366:Heinz Bodies / Q000378:metabolism; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D008875:Middle Aged
D008565:Membrane Proteins; D004226:Dithioerythritol; D000252:Calcium-Transporting ATPases; D005978:Glutathione; D002118:Calcium