Erythrocyte glutathione concentration and production during hyperinsulinemia, hyperglycemia, and endotoxemia in healthy humans.
In diabetes mellitus and sepsis, low erythrocyte glutathione (GSH) concentrations are found. Whether this is caused by lowered GSH production has not been clarified. To obtain insight in the relationship between erythrocyte GSH concentrations and GSH production, GSH kinetics were measured in healthy male volunteers during 4 different clamps (low-dose or medium-dose insulin [100 or 400 pmol/L] and euglycemia or hyperglycemia [5 or 12 mmol/L]) in a control setting (n = 6; all 4 clamps in the same subject) or after systemic administration of lipopolysaccharide (to mimic sepsis) (4 groups of n = 6; each clamp in a different subject). Hyperinsulinemia decreased erythrocyte GSH concentration (P = .042), but did not affect fractional synthetic rate (FSR) of GSH. Hyperglycemia did not affect erythrocyte GSH concentration, but decreased FSR of GSH (P = .025). Lipopolysaccharide decreased erythrocyte GSH concentration (P < .001), but increased FSR of erythrocyte GSH (P = .035). Depending on the metabolic circumstances, we found either stable GSH concentrations with lower production rates or decreased levels with either no change or an increase in production rate. Based upon these data, it seems inappropriate to infer conclusions about changes in synthesis rate of GSH from changes in its concentration.
van der Crabben
Saskia N
SN
Department of Endocrinology and Metabolism, Academic Medical Center, 1100 DD Amsterdam, The Netherlands. s.n.vandercrabben@umcutrecht.nl
Stegenga
Michiel E
ME
Blümer
Regje M E
RM
Ackermans
Mariëtte T
MT
Endert
Erik
E
Tanck
Michael W T
MW
Serlie
Mireille J
MJ
van der Poll
Tom
T
Sauerwein
Hans P
HP
D001786:Blood Glucose / Q000032:analysis; D018592:Cross-Over Studies; D019446:Endotoxemia / Q000378:metabolism*; D004912:Erythrocytes / Q000378:metabolism*; D005978:Glutathione / Q000096:biosynthesis / Q000097:blood*; D006801:Humans; D006943:Hyperglycemia / Q000378:metabolism*; D006946:Hyperinsulinism / Q000378:metabolism*; D007328:Insulin / Q000097:blood; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male
D001786:Blood Glucose; D007328:Insulin; D008070:Lipopolysaccharides; D005978:Glutathione