Determination of reliable bioindicators of diabetes-induced oxidative
stress and the role of dietary vitamin E supplementation
were investigated. Blood (plasma) chemistries, lipid peroxidation
(LPO), and antioxidant enzyme activities were measured over
12 weeks in New Zealand White rabbits (control, diabetic, and diabetic +
vitamin E). Cholesterol and triglyceride levels did not correlate
with diabetic state. PlasmaLPOwas influenced by diabetes and
positively correlated with glucose concentration only, not cholesterol
or triglycerides. Liver glutathione peroxidase (GPX) activity
negatively correlated with glucose and triglyceride levels. Plasma
and erythrocyte GPX activities positively correlated with glucose,
cholesterol, and triglyceride concentrations. Liver superoxide dismutase
activity positively correlated with glucose and cholesterol
concentration. Vitamin E reduced plasma LPO, but did not affect
the diabetic state. Thus, plasmaLPOwas the most reliable indicator
of diabetes-induced oxidative stress. Antioxidant enzyme activities
and types of reactive oxygen species generated were tissue dependent.
Diabetes-induced oxidative stress is diminished by vitamin E
supplementation