Identification of Hypoglycemic Components in Cinnamon Using Cell-based Insulin Resistance and Enzyme Inhibition Models and Mass Spectrometry Analysis

Abstract:

Four different extracts of cinnamon powder were prepared using the solvents water, anhydrous ethanol, petroleum ether, and ethyl acetate. A model of insulin resistance was established using 3T3-L1 preadipocytes to evaluate the hypoglycemic effects of different solvent extracts. Next, α-amylase and α-glucosidase inhibition assays were performed to track and isolate the hypoglycemic components in the extracts. Thereafter, these components were identified. CCK-8 cell viability results showed that all four solvent extracts exhibited low cytotoxicity toward 3T3-L1 cells at concentrations below 100 μg/mL. In addition, the ethyl acetate extract demonstrated good hypoglycemic activity at concentrations of 10, 20, and 50 μg/mL. In contrast, the ethyl acetate extract was less effective at α-glucosidase inhibition than the water extract, but displayed the highest α-amylase inhibitory activity. Based on these observations and our cell-based experiment results, the cinnamon extract in ethyl acetate was selected for further isolation. The F5 fraction obtained by silica gel column chromatography exhibited strong hypoglycemic effects, and the α-amylase and α-glucosidase inhibition rates were 66.08% and 98.21%, respectively. According to mass spectrometry analysis, the main constituents of the F5 fraction were transcinnamaldehyde and 4-methoxycinnamaldehyde, with relative molecular weights of 132.06 and 162.07, respectively. Transcinnamaldehyde and cinnamaldehyde exhibited specific hypoglycemic activities. These findings can serve as a valuable resource for further development and utilization of cinnamon as a hypoglycemic dietary supplement.