ANTI-DIABETIC ACTIVITIES OF 80% METHANOL EXTRACT AND SOLVENT FRACTIONS OF CROTON MACROSTACHYUS HOCHST. EX DELILE (EUPHORBIACEAE)

Abstract

Background: Diabetes mellitus (DM) is a chronic metabolic disorder characterized by high blood sugar levels. Managing DM has been challenging due to limited treatment options, high costs, and potential side effects of conventional medications. Medicinal plants have long been used traditionally to treat DM. Recent researches also suggested these plants may effectively lower blood glucose levels. Hence, medicinal plants can offer a promising alternative to conventional anti-diabetic medications. Objective: The study aimed to investigate the in vivo anti-diabetic activities of Croton macrostachyus roots. Methods: Anti-hyperglycemic and hypoglycemic effects of the 80% methanol crude extract and solvent fractions were evaluated in normoglycemic, oral glucose loaded, and Streptozotocin (STZ)-induced diabetic mice models. Randomly selected mice of either sex were used for the normoglycemic and oral glucose loaded mice models, while only male mice were used for the STZ-induced diabetic mice model. To assess the effects of the crude extract and each solvent fractions three dose ranges (100 mg/kg, 200 mg/kg, and 400 mg/kg). Results were compared using One-way ANOVA followed by Tukey's post hoc test. Data analysis was performed using SPSS (Statistical Package for Social Sciences), version 26. Measurements with p-value<0.05 were considered statistically significant. Results: The crude extract exhibited no signs of toxicity at a single 2000 mg/kg dose, suggesting the lethal dose (LD50) to be higher than 2000 mg/kg. The crude extract along with the chloroform fraction and ethyl acetate fractions significantly (p<0.01) reduced blood glucose levels in normoglycemic mice in a dose and time-dependent manner compared to the negative control (NC). The crude extract and chloroform fraction (200 mg/kg and 400 mg/kg) and the ethyl acetate fraction (400 mg/kg) showed a significant (p<0.01) glucose tolerance compared to NC. No significant difference in glucose tolerance was observed between glibenclamide, crude extract (400 mg/kg), chloroform fraction (400 mg/kg) and ethyl acetate fraction (400 mg/kg). In the STZ-induced diabetic mice model, the crude extract (400 mg/kg), the chloroform fraction (400 mg/kg) and the ethyl acetate fraction (400 mg/kg) significantly (p<0.001) reduced fasting glucose levels compared to NC, and were responsible for 30%, 24% and 22% reduction, respectively. VII | P a g e Conclusions: The results of the study have demonstrated that the crude extract, chloroform fraction and ethyl acetate fraction of Croton macrostachyus roots possess a promising anti diabetic effect, which may be attributed to the presence of bio-active phytochemicals. Therefore, the current findings provide scientific support for the ethnomedicinal utilization of the plant for the treatment of DM.