Background and Objective: Diabetes is a major
global public health problem caused by impaired
insulin secretion and action. The complications of
diabetes are the leading cause of death in diabetic
patients. In the present study, the effects of
tetrahydrocurcumin (THU), a strong antioxidant are
assessed on plasma glucose, insulin levels, insulin
resistance, and oxidative stress in streptozotocinnicotinamide
(STZ-NA) diabetic rats.
Methods: Forty male Wistar rats were randomly
divided into five groups: 1) control, 2) control
treated with THU (100 mg/kg/day), 3) diabetic, 4)
diabetic treated with THU 50 mg/kg/day, and 5)
diabetic treated with THU 100 mg/kg/day. Diabetes
was induced by injection of STZ 55 mg/kg/day after
a dose of NA 110 mg/kg/day. Eight weeks after oral
administration of THU, plasma glucose levels, insulin
levels, insulin sensitivity, oxidative stress markers
including plasma malondialdehyde (MDA) and
plasma protein carbonyl, and antioxidant glutathione
(GSH) levels were evaluated.
Results: Diabetic rats showed hyperglycemia, insulin
resistance, and impaired glucose tolerance, (p<0.05
compared with non-diabetic rats). These alterations were associated with oxidative stress, as the evidence
of increasing MDA and protein carbonyl (p<0.05).
Moreover, intracellular GSH were significantly
decreased in those rats. Treatment with THU in
dose-dependently decreased fasting blood glucose
levels, improved insulin sensitivity, and alleviated
oxidative stress in diabetic rats.
Conclusions: THU exerts a beneficial effect on
minimizing hyperglycemia in diabetic rats. The
mechanism might involve the glucose-lowering effect
by improving insulin sensitivity, and antioxidant
activity of THU.