Ajuga iva treatment is more effective to improve the antioxidant capacity of red blood cells than that of tissues in hypercholesterolemic rats
The effects of aqueous extract of Ajuga iva (L.) Schreber (Lamiaceae) (Ai) were investigated on redox status of hypercholesterolemic (HC) rats in red blood cells (RBC) and tissues. Male Wistar rats (n=12) were fed on 1% cholesterol-enriched diet for 15d. After this adaptation phase, HC-rats (total cholesterol=6.5±0.6mmol/L) were divided into two groups fed the same diet and treated or not with Ai (0.5% in the diet) for 15d. Lipid peroxidation was determined by analysis of thiobarbituric acid reactive substances (TBARS) in serum  and tissues . Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione reductase (GSSH-Red) and catalase activity was determined. In Ai-treated HC-group, TBARS concentrations, LDL-HDL1, HDL2 and HDL3 were respectively, 5-, 7.8-, 2.3- and 5-fold lower in serum, 1.4-fold lower in heart and 2.8-fold higher in kidney than in untreated group. SOD activity was respectively, 1.2- and 1.4-fold higher in RBC and muscle. GSH-Px and GSSH-Red were enhanced in RBC (+9%, and +12%, respectively). GSSH-Red activity was 1.4- and 1.5-fold higher in adipose tissue and heart, respectively and 3.7-fold lower in kidney. Liver catalase activity was 1.6-fold higher. Adipose tissue and muscle total glutathione content represented in Ai treated group 35% and 36% of the value noted in untreated group. Ai treatment enhanced α-tocopherol contents (+25%). In conclusion, Ajuga iva treatment is more effective to improve the antioxidant capacity of RBC than that of tissues studied. Indeed, Ai is able to reduce the oxidative stress in hypercholesterolemic rats by increasing the antioxidant enzymes activity. The antioxidant defense status in HC-rats treated with Ai might be correlated to flavonoids characterized from this plant.
Acknowledgements: this work was supported by the French Foreign Office (International Research grants 04 MDU 629).
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