Antidiabetic Activity And Safety Of Piper Capense, Berberis Holstii, Sonchus Asper, Vernonia Lasiopus And Galinsoga Parviflora In Alloxan-Induced Diabetic Albino Mice

ABSTRACT

In Kenya, diabetes mellitus is of health concern to the public, because it causes substantial morbidity, mortality, and long-term complications. Synthetic drugs used in the management of diabetes are unavailable, have numerous side effects and are expensive. Many plants such as Piper capense, Berberis holstii, Sonchus asper, Vernonia lasiopus and Galinsoga parviflora used traditionally to manage many diseases including diabetes mellitus but their efficacy and safety after long-term use are not scientifically validated. This study aimed to determine in vivo antidiabetic activity and safety of aqueous plant extracts of Piper capense, Berberis holstii, Sonchus asper, Vernonia lasiopus and Galinsoga parviflora in male albino mice. Aqueous plant extracts were screened for antidiabetic activity in diabetic mice using the intraperitoneal and the oral routes. In the study, albino mice were assigned into eight groups of five mice each. For this purpose, reduction in blood glucose relative to their initial values was determined after oral and intraperitoneal administration of 25, 48.4, 93.5, 180.9, and 350 mg of aqueous extracts/kg body weight. 1IU/kg body weight dose of insulin and 4.6 mg of glibenclamide (200 mg/kg body weight) were used as a standard hypoglycemic agent to compare the results. Glucose levels were estimated at the beginning of the experiment and repeated after 2, 4, 6, 8, 10 and 24 hours after administering the drugs. Significant reduction in blood glucose relative to their initial values was determined for all treated non-diabetic and diabetic groups at the end of experiment. Mineral composition of the aqueous plant extracts was determined using TRXF (total reflection X-ray fluorescence system) while the quantities and types of phytochemicals present were determined using standard procedures. Toxicity of the aqueous plant extracts to normal mice was studied by orally and intraperitoneally administering them with 450, 670 and 1000 mg/kg body weight daily for 28 days and kept under close observation. Changes in body and organ weight, hematological and biochemical parameters were also determined. After the 28th day, mice were sacrificed and pieces of pancreas, lungs, brain, testis, heart, kidney, spleen and livers were removed for weight change evaluation. Aqueous extracts orally and intraperitoneally administered at 25, 48.4, 93.5, 180.9, and 350 mg/kg body weight showed antidiabetic activity through either route. Oral and intraperitoneal dose of 450, 670 and 1000 mg/kg body weight of the plant extracts significantly reduced the body weight gain. The same oral and intraperitoneal dose of Piper capense, Berberis holstii, Sonchus asper, Vernonia lasiopus and Galinsoga parviflora altered the hemoglobin levels, mean cell hemoglobin concentration, platelets, red blood cell count, packed cell volume, mean cell volume, white blood cell count and their differential counts. The dose also altered activities of aspartate and alanine aminotransferases, alkaline phosphatase, α-amylase and lactate dehydrogenase. The plants extract contained phenols, tannins, saponins, flavonoids, and alkaloids. Minerals present were potassium, calcium, titanium, bromine, iron, zinc, copper, chromium, manganese, vanadium, rhubidium, strontium, and heavy metal lead. The observed antidiabetic activity toxicity observed in the plants extracts could be due to the phytochemicals and minerals present in the plants extracts. The study recommends use of safe plants with antidiabetic activity as herbal remedies. Comprehensive safety studied on the plants and organic solvent extraction for comparison of the activities of both organic and aqueous extracts.