South African J Bot. 154, 330-355, 2023
Diabetes mellitus is the most prevalent metabolic disease, and almost 1200 plants are reported with hypoglycaemic potential. Some of these plants are scientifically proven for the hypoglycaemic and antidiabetic effects. This study was designed to assess the hypoglycaemic effect of Sambucus wightiana Wall. ex Wight & Arn. extract in streptozotocin-nicotinamide induced diabetic Wistar Albino rats. An acute toxicity study was performed to establish the safe dose of total alkaloids extracted from S. wightiana (TASW). TASW was administered orally (50 mg, 100 mg, and 200 mg/kg body weight per day) to diabetic rats for 21 days. Fasting blood glucose level was determined, along with other associated parameters that may fluctuate in diabetes, consisting of the lipid profile, body weight, serum liver marker enzymes and Hb level. The test groups that were administered TASW at three different doses showed a marked reduction in hyperglycaemia when compared to the control group. Moreover, body weight and food intake improved among test group animals. Administration of TASW also reduced the levels of triglycerides, cholesterol and LDL while increasing HDL and Hb levels. Serum liver enzyme activity is generally increased in diabetes, and this was reduced after dosing with TASW. The findings of this study elucidate that the total alkaloids extracted from S. wightiana are not toxic at the tested doses, and present potential hypoglycaemic activity.
