Evaluation of Antidiabetic Properties of the Leaves Extract of Ficus vallis-choudae Delile in a Model of Type 2 Diabetes Induced by High-Fat Diet and Streptozotocin.

This work aimed to determine the phytochemical composition of the aqueous extract of leaves of Ficus vallis-choudae (AEFV) and to evaluate its antidiabetic properties on a model of type 2 diabetes induced by a high-fat diet (HFD) and a low dose of streptozotocin (STZ). The phytochemical analysis was carried out according to several methods using the standard of each bioactive compound. Type 2 diabetes was induced by feeding rats for 4 weeks with HFD lard followed by injection of a low dose of STZ (35 mg/kg). After induction, the rats were divided into groups and treated for 28 days with metformin (40 mg/kg) and the AEFV at doses of 110, 220, and 440 mg/kg. The results showed that the AEFV contains saponins, flavonoids, tannins, and total polyphenols. In addition, it dramatically reduced body mass, body mass index (BMI), atherogenic index (AI), coronary heart risk index (CRI), and abdominal fat and increased homeostatic model assessment of ß-cell function (HOMA-ß), high-density lipoprotein cholesterol (HDL-c) levels, and cardioprotective index (CI). The AEFV also lowered blood glucose levels, insulinemia, homeostatic model assessment of insulin resistance (HOMA-IR) index, and total cholesterol (TC), triglycerides (TG), low-density lipoproteins cholesterol (LDL-c), and very-low-density lipoproteins cholesterol (VLDL-c) levels. There was a decrease in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity and in urea and serum creatinine levels following the administration of AEFV. The AEFV caused increased superoxide dismutase (SOD) and catalase (CAT) activities, reduced glutathione (GSH) levels, and decreased malondialdehyde (MDA) levels in the liver, kidneys, and heart of rats. The AEFV has hypoglycemic, antioxidant, and cardioprotective properties, thus validating its use in traditional medicine for the treatment of type 2 diabetes and its complications.

Tapinanthus dodoneifolius leaf inhibits the activity of carbohydrate digesting enzymes and improves the insulin resistance induced in rats by dexamethasone.

Background: Tapinanthus dodoneifolius is a plant used in traditional African medicine to treat diabetes mellitus. This study aimed to evaluate the preventive antidiabetic potential of the aqueous extract of T. dodoneifolius leaves (AETD) in insulin resistant rats. Methods: A quantitative phytochemical study of AETD was carried out to determine the contents of total phenols, tannins, flavonoids, and saponins. AETD was tested in vitro on the activity of α-amylase and α-glucosidase enzymes. Insulin resistance was induced for 10 days by daily subcutaneous injection of dexamethasone (1 mg/kg). One hour before, the rats were divided into 5 groups and treated as follows: group 1 received distilled water (10 mL/kg); group 2 received metformin (40 mg/kg), and groups 3, 4, and 5 were treated with AETD (125, 250, and 500 mg/kg). Body weight, blood sugar, food and water consumption, serum insulin level, lipid profile, and oxidative status were assessed. One-way analysis of variance followed by Turkey's post-test and two-way analysis followed by Bonferroni's post-test were used to analyze univariate and bivariate parameters, respectively. Results: Results showed that the phenol content of AETD (54.13 ± 0.14 mg GAE/g extract) was higher than that of flavonoids (16.73 ± 0.06 mg GAE/g extract), tannins (12.08 ± 0.07 mg GAE/g extract), and saponins (IC50 = 13.56 ± 0.03 mg DE/g extract). AETD showed a higher inhibitory potential on α-glucosidase activity (IC50 = 191.51 ± 5.63 µg/mL) than on α-amylase activity (IC50 = 1774.90 ± 10.32 µg/mL). AETD (250 and/or 500 mg/kg) prevented drastic loss of body weight and reduced food and water consumption in insulin resistant rats. The levels of blood glucose, total cholesterol, triglycerides, low-density lipoprotein cholesterol, and malondialdehyde were also reduced while high-density lipoprotein cholesterol level, reduced glutathion level, and catalase and superoxide dismutase activity increased after administration of AETD (250 and 500 mg/kg) in insulin resistant rats. Conclusion: AETD has significant antihyperglycemic, antidyslipidemic, and antioxidant potential, thus it can be used for the management of type 2 diabetes mellitus and its complications.