title: O(2)-dependent stimulation of the pentose phosphate pathway by S-nitrosocysteine in human erythrocytes.
abstract: 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.
authors.affiliation: Istituto di Biochimica e Biochimica Clinica, Facoltà di Medicina e Chirurgia, Università Cattolica del Sacro Cuore. L.go F. Vito 1, 00168 Rome, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Misiti
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Meucci
authors.forename: Cecilia
authors.initials: C
authors.lastname: Zuppi
authors.forename: Federica
authors.initials: F
authors.lastname: Vincenzoni
authors.forename: Bruno
authors.initials: B
authors.lastname: Giardina
authors.forename: Massimo
authors.initials: M
authors.lastname: Castagnola
authors.forename: Irene
authors.initials: I
authors.lastname: Messana
mesh_terms: 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
chemical_list: 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