Time course of oxidative stress status in the postprandial and postabsorptive states in type 1 diabetes mellitus: relationship to glucose and lipid changes.
OBJECTIVE
The aim of this study was to compare oxidative stress status (OSS) with blood glucose and lipid changes during the fasting, postprandial and postabsorptive phases in type 1 diabetes mellitus.


METHODS
Twenty-three patients on intensive insulin treatment received a standard fat-rich breakfast and lunch. OSS was monitored at fasting (F), just after the post-breakfast glycemia peak (BP) (identified by continuous subcutaneous glucose monitoring), 3.5-h post-breakfast (B3.5), just after the post-lunch peak (LP), just after the post-lunch dale (LD) and 5 hours after lunch (L5).


RESULTS
Whereas whole blood glutathione and plasma protein thiols increased in the postprandial period (from 6.52 +/- 1.20 (F) to 7.08 +/- 1.45 micromol/g Hb (BP), p = 0.005), ascorbate decreased gradually from 44 +/- 17 (F) to 39 +/- 19 micromol/L (LD), p = 0.015. Retinol and alpha-tocopherol also decreased from 27.1 +/- 7.0 (F) to 25.3 +/- 5.2 micromol/L (BP), p = 0.005. Uric acid decreased later, from 213 +/- 77 (BP) to 204 +/- 68 micromol/L (B3.5), p = 0.01, but then increased in LP (231 +/- 70 micromol/L) and LD to values higher than F (215 +/- 64, micromol/L, p = 0.01). Malondialdehyde increased gradually from 1.02 +/- 0.36 (F) to a maximum of 1.14 +/- 0.40 micromol/L (LP). In the postabsorptive phase (L5) all parameters except for thiols reverted to fasting concentrations.


CONCLUSIONS
In type 1 diabetes lipid peroxidation increases during the postprandial phase in parallel to glucose and triglyceride changes. Blood antioxidants, however, followed diverse patterns of change.
Manuel-y-Keenoy
Begoña
B
University of Antwerp campus Drie Eiken, Metabolic Research Unit T4.37, Universiteitsplein 1, B-2610 Wilrijk-Antwerp, Belgium. begona.manuelykeenoy@ua.ac.be
Van Campenhout
Ann
A
Aerts
Petra
P
Vertommen
Jan
J
Abrams
Pascale
P
Van Gaal
Luc F
LF
Van Gils
Carolien
C
De Leeuw
Ivo H
IH
D000042:Absorption; D000328:Adult; D000975:Antioxidants / Q000378:metabolism*; D019540:Area Under Curve; D001786:Blood Glucose / Q000032:analysis*; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D005215:Fasting / Q000097:blood; D005260:Female; D005502:Food; D005978:Glutathione / Q000097:blood; D006801:Humans; D007328:Insulin / Q000378:metabolism; D015227:Lipid Peroxidation; D008055:Lipids / Q000097:blood*; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology*; D019518:Postprandial Period; D014280:Triglycerides / Q000097:blood
D000975:Antioxidants; D001786:Blood Glucose; D007328:Insulin; D008055:Lipids; D014280:Triglycerides; D005978:Glutathione