Antihyperglycemic Activity of Caralluma fimbriata: An In vitro Approach

BACKGROUND: An increase in prevalence of diabetes mellitus necessitates the need to develop new drugs for its effective management. Plants and their bioactive compounds are found to be an alternative therapeutic approach. Caralluma fimbriata, used in this study, is well known for its various biological effects. OBJECTIVE: The present study was designed to investigate the antihyperglycemic effect of the ethanolic leaf extract of C. fimbriata. MATERIALS AND METHODS: Different concentrations (1–1000 mg/mL) of the ethanolic leaf extract of C. fimbriata were subjected to alpha-amylase and alpha-glucosidase inhibitory assay with acarbose as control. Cytotoxicity was assessed by 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Glucose uptake assay was performed on L6 myotubes using the extract in 1 μg–100 μg/mL, using metformin and insulin as control. RESULTS: The C. fimbriata extract showed potent inhibitory activity on enzymes of glucose metabolism in a dose-dependent manner. The maximum alpha-amylase inhibitory effect was 77.37% ± 3.23% at 1000 μg/mL with an IC(50) value of 41.75 μg/mL and alpha-glucosidase inhibitory effect was 83.05% ± 1.69% at 1000 μg/mL with an IC(50) value of 66.71 μg/mL. The maximum glucose uptake was found to be 66.32% ± 0.29% for the Caralluma extract at 100 μg/mL and that of metformin (10 μg/mL) was 74.44% ± 1.72% and insulin (10 mM) 85.55% ± 1.14%. The extract was found to be safe as the IC(50) of extract and metformin was found to be ≥1000 μg/mL and ≥1000 μM, respectively, in the cell line tested. CONCLUSION: The study concludes that C. fimbriata has promising antihyperglycemic activity. SUMMARY: Caralluma fimbriata extract exhibited effective dose dependent inhibitory activity against alpha-amylase and alpha- glucosidase. Enhanced glucose uptake from L6 myotubes was appreciated in the presence of the extract, comparable to Insulin and metformin. Caralluma fimbriata has potent antihyperglycemic properties. [Image: see text] Abbreviations used: GLUT: Glucose transporter; MTT: 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide.