Hypolipidemic activity of Tamarix articulata Vahl. in diabetic rats.

Objective: Tamarix articulata Vahl. (Tamaricaceae) is a medicinal plant commonly used in Morocco for the treatment of diabetes mellitus and cardiovascular diseases. The objective of this study was to evaluate the hypolipidemic activity of aqueous extract of T. articulata in normal and streptozotocin (STZ)-induced diabetic rats. Phytochemical analysis as well as determination of polyphenol and flavonoid contents in the aqueous extract of T. articulata was performed.

Methods: The effects of oral administration of aqueous extract of T. articulata (5 mg/kg) on the plasma total cholesterol, triglyceride and high-density lipoprotein cholesterol (HDL-c) concentrations were measured in both normal and STZ-induced diabetic rats. Total phenolic content of the aqueous extract was determined by Folin-Ciocalteu method. In addition, determination of flavonoid content was performed using colorimetric AlCl3 method.

Results: A single oral administration in diabetic rats induced a significant increase in the HDL-c concentration after 6 h of treatment with T. articulata (5 mg/kg). The results also demonstrated that the aqueous extract of T. articulata produced a significant decrease of serum total cholesterol after repeated oral administration in diabetic rats (P < 0.01). The total polyphenol and flavonoid contents of T. articulata aqueous extract were equal to 102.50 mg of gallic acid equivalent per gram of extract and 54.83 mg of quercetin equivalent per gram of extract, respectively.

Conclusion: According to preliminary phytochemical screening of the aerial part of T. articulata, several classes of chemicals have been found, such as polyphenols, flavonoids, tannins, cyanidins (flavones, catechols), mucilage, sesquiterpenes, terpenoids and carbohydrates. In conclusion, T. articulata exhibits a hypolipidemic effect in diabetic rats and its beneficial role as hypolipidemic agent should be evaluated in clinical studies.