Decreased stimulation by 12-O-tetradecanoylphorbol-13-acetate of superoxide radical production by polymorphonuclear leukocytes carrying the Mediterranean variant of glucose-6-phosphate dehydrogenase.
Polymorphonuclear leukocytes (PMNs) from individuals carrying the Mediterranean variant of glucose-6-phosphate dehydrogenase (G6PD) exhibit a great decrease in this enzymatic activity and in hexose monophosphate shunt (HMS). 12-O-tetradecanoylphorbol-13-acetate (TPA) greatly stimulates HMS of normal PMNs, while it does not affect that of the deficient PMNs. Similarly, the stimulation of HMS by methylene blue is largely reduced in G6PD-deficient PMNs. These changes are paralleled by a 58% decrease in TPA-stimulated superoxide radical (O2-) formation by the deficient PMNs. G6PD activity is not detectable in the deficient PMNs incubated with dehydroepiandrosterone, and these cells show a near complete inhibition of O2- production. It thus seems that the low ability of G6PD-deficient PMNs in the production of O2- depends on the low NADPH generation by HMS in these cells. The decrease in TPA-stimulated O2- production suggests a reduced response of G6PD-deficient cells to promoting agents.
Pascale
R
R
Istituto di Patologia generale, Università di Sassari, Italy.
Garcea
R
R
Ruggiu
M E
ME
Daino
L
L
Frassetto
S
S
Vannini
M G
MG
Cozzolino
P
P
Lenzerini
L
L
Feo
F
F
Schwartz
A G
AG
D000328:Adult; D005609:Free Radicals; D005954:Glucosephosphate Dehydrogenase / Q000097:blood / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009249:NADP / Q000378:metabolism; D009504:Neutrophils / Q000187:drug effects* / Q000201:enzymology; D010427:Pentose Phosphate Pathway; D013481:Superoxides / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D005609:Free Radicals; D013481:Superoxides; D009249:NADP; D005954:Glucosephosphate Dehydrogenase; D013755:Tetradecanoylphorbol Acetate