Abstract: Objective: To study the effect of blueberry anthocyanins on liver antioxidant function and ultrastructure in
experimental diabetic rats. Methods: Forty experimental diabetic rats were randomly divided into 4 groups: diabetic mellitus
(DM), DM + L, DM + M and DM + H groups, and 20 normal rats were divided into 2 groups: normal control (NC) and NC +
H groups. The rats from the DM + L, DM + M and DM + H groups were subjected to gavage once a day for 4 weeks with
blueberry anthocyanins at 0.24, 0.48 and 0.96 mg/(g·d), respectively, those from the DM and NC groups received the
same volume of distilled water, and those from the NC + H group were given 0.96 mg/(g·d) of blueberry anthocyanins.
After 4 weeks, fasting blood glucose, and liver malonaldehyde (MDA) content, hydroxyl and superoxide anion radical
scavenging capacity, glutathion peroxidase (GSH-Px) activity and total antioxidant capacity (T-AOC) in the rats were
detected. Transmission electron microscope (TEM) was used to detect liver ultrastructure. Results: Blueberry anthocyanins
treatment could lower fasting blood glucose level and liver MDA content in experimental diabetic rats significantly
(P < 0.05), and increase liver anti-hydroxyl radical capacity, anti-superoxide anion radical capacity, GSH-Px activity and
T-AOC significantly (P < 0.05), while maintaining the integrity of liver cells. The best effect was observed at the high dose.
Conclusion: Blueberry anthocyanins could enhance liver antioxidant activity and protect the ultrastructure of liver cells.

Key words: blueberry, anthocyanins, diabetes, liver, antioxidant activity