Affordable Access

Publisher Website

Lowering Effects of Onion Intake on Oxidative Stress Biomarkers in Streptozotocin-Induced Diabetic Rats

Journal of Clinical Biochemistry and Nutrition
The Society for Free Radical Research Japan
Publication Date
DOI: 10.3164/jcbn.40.131
  • Original Article
  • Medicine


The protective effect of onion against oxidative stress in streptozotosin-induced diabetic rats was investigated in comparison with that of quercetin aglycone. We measured oxidative stress biomarkers involving the susceptibility of the plasma against copper ion-induced lipid peroxidation, which was estimated by the amounts of thiobarbituric acid-reactive substances (TBARS) and cholesteryl ester hydroperoxides, and urine TBARS and 8-hydroxydeoxyguanosine contents. After the 12-week feeding period, plasma glucose levels and these biomarkers increased in diabetic rats compared to normal rats. In diabetic rats fed a 6.0% onion diet (quercetin equivalent: 0.023%), quercetin metabolites accumulated in the plasma at concentrations of approximately 35 µM. Onion intake decreased plasma glucose levels and lowered the oxidative stress biomarkers. On the other hand, quercetin metabolites in the plasma of rats fed a diet with 0.023% quercetin aglycone were found at lower concentrations (14.2 µM) than the rats fed the onion diet. Furthermore, oxidative stress biomarkers were higher in the quercetin diet group compared to the onion diet group. These results strongly suggest that onion intake suppresses diabetes-induced oxidative stress more effectively than the intake of the same amount of quercetin aglycone alone.

There are no comments yet on this publication. Be the first to share your thoughts.


Seen <100 times

More articles like this

Effects of α-lipoic acid on biomarkers of oxidativ...

on The Journal of Nutritional Bio... Jan 01, 2003

Effects of alpha-lipoic acid on biomarkers of oxid...

on The Journal of Nutritional Bio... May 2003

Oxidative stress in streptozotocin-induced diabeti...

on Comparative Biochemistry and P... Jan 01, 2003

Effects of pycnogenol treatment on oxidative stres...

on Journal of Biochemical and Mol... 2003
More articles like this..