Antihyperglycemic, Antihyperlipidemic, and Antioxidant Effects of Salvia tingitana in Streptozotocin-Induced Diabetic Rats

Aims: The study aimed to assess the antidiabetic effect of Salvia tingitana (S. tingitana). Background: S. tingitana is an aromatic plant that belongs to the Lamiaceae family. Phytochemical analysis of the aerial parts of S. tingitana revealed the existence of terpenoids and flavonoids. In addition, S. tingitana possesses antimicrobial activity. Objective: The goal of the study was to obtain information about the antihyperglycemic, antihyperlipidemic, antioxidant abilities of S. tingitana aqueous extract. Methods: The effect of an acute and sub-chronic administration of S. tingitana aqueous extract (AEST) at the doses of 60 and 80 mg/kg on glucose, lipid profile, and lipoprotein profile was examined in normoglycemic and hyperglycemic rats. Additionally, a preliminary phytochemical screening and the antioxidant activity using DPPH assay were carried out. Results: Rats treated with AEST at a dose of 60 mg/kg showed a significant decrease in the serum glucose levels during the single oral administration at the 4th and 6th hour of treatment in both normal and streptozotocin(STZ)-induced hyperglycemic rats. Interestingly, a dose of 80 mg/kg AEST produced a significant lowering effect on blood glucose levels at the 2nd, 4th, and 6th hour of treatment after a single oral administration in both diabetic and normal rats. Both doses of AEST (60 and 80 mg/kg) revealed a significant amelioration of lipid and lipoprotein profile. In addition, the qualitative and quantitative phytochemical analysis proved the presence of polyphenols compounds, flavonoids, and tannins. Results suggest that S. tingitana contains some secondary metabolites like alkaloids, phenols, flavonoids, and saponins. Importantly, the study revealed that the aqueous extract of S. tingitana has a very interesting antioxidant activity (IC50 = 553.21 μg/ml). Conclusion: The study illustrates the beneficial action of the aqueous extract of S. tingitana as an antihyperglycemic and antihyperlipidemic agent.