Ps. Samiec et al., GLUTATHIONE IN HUMAN PLASMA - DECLINE IN ASSOCIATION WITH AGING, AGE-RELATED MACULAR DEGENERATION, AND DIABETES, Free radical biology & medicine, 24(5), 1998, pp. 699-704
Blood samples were analyzed for GSH and GSH redox state in 40 age-rela
ted macular degeneration (ARMD) patients (> 60 y), 33 non-ARMD diabeti
c patients (> 60 years), 27 similarly aged non-ARMD and nondiabetic in
dividuals (> 60 years), and 19 younger individuals (< 60 years) withou
t ARMD or diabetes. Results showed a significantly lower plasma GSH in
older individuals (ARMD, diabetes, and controls) than in younger indi
viduals (p < .01). Total GSH (GSHt) obtained following treatment with
dithiothreitol was significantly lower only in diabetic cases (p < .05
) but also approached significance for ARMD cases (p = .089). Estimati
on of redox potential indicated that the plasma GSH pool is considerab
ly more oxidized in all of the older groups. Analyses of whole blood G
SH showed that GSH was significantly lower in diabetic cases compared
to the other groups, but did not reveal any difference associated with
age or ARMD. In contrast, GSSG in whole blood was significantly highe
r in the older groups compared to the younger controls. The results su
ggest that in studies of age-related pathologies, oxidation of GSH may
be a more important parameter than a decline in pool size, while in s
pecific pathologies such as diabetes, both oxidation and a decline in
pool size may be important. (C) 1998 Elsevier Science Inc.