Modulation of oxidative stress by Chlorella vulgaris in streptozotocin (STZ) induced diabetic Sprague-Dawley rats.

ABSTRACT

PURPOSE: Chlorella vulgaris (CV), a fresh water alga has been reported to have hypoglycemic effects. However, antioxidant and anti-inflammatory effects of CV in diabetic animals have not been investigated to date. The aim of the present study was to investigate the role of CV in inflammation and oxidative damage in STZ-induced diabetic rats. MATERIALS AND METHODS: Male Sprague-Dawley rats (300 - 400g) were divided into 4 groups control, CV, STZ-induced diabetic rats, and STZ rats treated with CV (150mg/kg body wt). Blood samples were drawn from orbital sinus at 1 and 4 weeks for determination of oxidative cellular damage (DNA damage and lipid peroxidation [malondialdehyde, MDA]), inflammation (tumour necrosis factor alpha, TNF-α) and antioxidant status (catalase, CAT, and superoxide dismutase, SOD). RESULTS: CV did not have any effects on glucose levels in diabetic rats, over the 4 weeks of treatment. However, it reduced significantly DNA damage and blood MDA levels in STZ-induced diabetic rats compared to the control group. Plasma levels of TNF-α however did not show any significant changes in STZ-induced diabetic rats fed with CV. Antioxidant enzyme SOD showed no significant changes in all groups but CAT activity was reduced in STZ-induced diabetic rats compared to the control. CONCLUSIONS: CV did not have hypoglycaemic effect but it has a protective role in STZ-induced diabetic rats by reducing oxidative DNA damage, and lipid peroxidation.