RESUMO
BACKGROUND: Diabetes mellitus (DM), a prevalent non-communicable disease, is a metabolic condition involving defective pancreatic ß-cells and/or insulin resistance. Researchers are presently exploring traditional medicinal plants to identify alternatives for treating diabetes due to the various disadvantage of current anti-diabetic medicines. OBJECTIVE: The present study evaluated the anti-hyperglycaemic effects of ethanol extracts of five medicinal plants (EEMPs) (Gynura nepalensis, Glochidion thomsonii, Clerodendrum splendens, Clerodendrum infortunatum and Xanthium strumarium) which are traditionally used as an ethnomedicine to treat diabetes and numerous other health problems. METHODS: High-fat fed (HFF) obese rats were used to perform acute in vivo tests, including oral glucose tolerance, feeding test, metabolic studies, and gastrointestinal motility using BaSO4 milk solution. Priliminary phytochemical screening were performed to discover the presence or absence of alkaloids, tannins, saponins, steroids, glycosides, flavonoids, and reducing sugars in extracts. RESULTS: Oral administration of ethanol extracts (250 mg/kg, body weight), along with glucose (18 mmoL/kg body weight), ameliorated glucose tolerance (p < 0.05-0.01). In addition, the extracts improved gut motility (250 mg/kg; p < 0.05-0.001), as well as reduced food intake during the feeding test (250 mg/kg; p < 0.05-0.001). Phytochemical screening of these medicinal plants depicted the presence of flavonoids, alkaloids, tannins, saponins, steroids and reducing sugars. CONCLUSIONS: Phytochemicals such as flavonoids, tannins and saponins may be responsible for the glucose-lowering properties for these plants. Additional research is warranted to fully identify the bioactive phytomolecules and mechanistic pathways that might lead to the development of a viable, cost-effective type 2 diabetes therapy.
