O(2)-dependent stimulation of the pentose phosphate pathway by S-nitrosocysteine in human erythrocytes.
In the present study we analysed the effects of S-nitrosocysteine (CysNO) on adult human red blood cell metabolism and observed that metabolic response depended on the degree of cell oxygenation. In particular, glucose metabolised through the pentose phosphate pathway (PPP) was higher in treated erythrocytes than in untreated cells only at high O(2) pressure. Since, following the treatment of intact cells with CysNO, glucose-6-phosphate dehydrogenase (G6PD) and phosphofructokinase (PFK) activities did not evidence any significant alteration, the possibility that the stimulation of PPP was triggered by a CysNO mediated modification of these enzymes was excluded. Intracellular S-nitrosoglutathione (GSNO), detected only in treated red blood cells, may be linked solely to the exposition to the NO donor. A possible rationalisation of the different metabolic behaviour shown by erythrocytes as a function of their oxygenation state is proposed. It takes into account the different route of catabolic degradation observed in vitro for GSNO under aerobic and anaerobic condition.
Misiti
Francesco
F
Istituto di Biochimica e Biochimica Clinica, Facoltà di Medicina e Chirurgia, Università Cattolica del Sacro Cuore. L.go F. Vito 1, 00168 Rome, Italy.
Meucci
Elisabetta
E
Zuppi
Cecilia
C
Vincenzoni
Federica
F
Giardina
Bruno
B
Castagnola
Massimo
M
Messana
Irene
I
D003545:Cysteine / Q000031:analogs & derivatives* / Q000378:metabolism*; D019075:Electrophoresis, Capillary; D004912:Erythrocytes / Q000378:metabolism*; D005947:Glucose / Q000493:pharmacokinetics; D005954:Glucosephosphate Dehydrogenase / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D006019:Glycolysis; D006461:Hemolysis; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D009569:Nitric Oxide / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism*; D010427:Pentose Phosphate Pathway; D025221:Phosphofructokinases / Q000378:metabolism; D026422:S-Nitrosoglutathione / Q000378:metabolism; D026403:S-Nitrosothiols / Q000378:metabolism*; D013997:Time Factors
D026403:S-Nitrosothiols; D009569:Nitric Oxide; D026422:S-Nitrosoglutathione; C021315:S-nitrosocysteine; D005954:Glucosephosphate Dehydrogenase; D025221:Phosphofructokinases; D005978:Glutathione; D005947:Glucose; D003545:Cysteine; D010100:Oxygen