Glutamine plays a role in superoxide production and the expression of p47phox, p22phox and gp91phox in rat neutrophils.
The effect of glutamine on the activity of the NADPH oxidase complex from rat neutrophils was investigated. Superoxide anion (O(2)(-)) production was assessed: (1) by scintillation counting by using lucigenin, and (2) by reduction of cytochrome c over 10 min. The effects of glutamine and PMA on the expression of the NADPH oxidase components p22( phox ), gp91( phox ) and p47( phox ) were also determined. Glutamine at 1 and 2 mM increased O(2)(-) generation in the presence of PMA by 100% and 74% respectively, in neutrophils maintained previously for 3 h in medium deprived of this amino acid. DON (6-diazo-5-oxo-L-norleucine), an inhibitor of phosphate-dependent glutaminase and thus of glutamine metabolism, caused a significant decrease in O(2)(-) production by neutrophils stimulated with PMA both in the absence (44%) and in the presence (66%) of glutamine. PMA markedly increased the expression of gp91( phox ), p22( phox ) and p47( phox ) mRNAs. Glutamine (2 mM) increased the expression of these three proteins both in the absence and in the presence of PMA. We postulate that glutamine leads to O(2)(-) production in neutrophils, probably via the generation of ATP and regulation of the expression of components of NADPH oxidase.
Pithon-Curi
Tania Cristina
TC
Camilo Castelo Branco University and Methodist University of Piracicaba-FACEF, Rua Carolina Fonseca 584, 08230-030 São Paulo, Brazil. tcuri@fisio.icb.usp.br
Levada
Adriana C
AC
Lopes
Lúcia R
LR
Doi
Sonia Q
SQ
Curi
Rui
R
D000818:Animals; D001798:Blood Proteins / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D005973:Glutamine / Q000494:pharmacology* / Q000502:physiology; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins; D009252:NADPH Dehydrogenase / Q000235:genetics / Q000378:metabolism; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases / Q000187:drug effects* / Q000378:metabolism; D009504:Neutrophils / Q000187:drug effects* / Q000378:metabolism; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013481:Superoxides / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D001798:Blood Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D010750:Phosphoproteins; C039077:platelet protein P47; D005973:Glutamine; D013481:Superoxides; C056558:CYBB protein, human; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases; C086986:CYBA protein, human; D009252:NADPH Dehydrogenase; D013755:Tetradecanoylphorbol Acetate