基于细胞胰岛素抵抗及酶抑制模型筛选肉桂降糖成分和质谱分析

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

摘要:

该研究以肉桂粉为原料，利用水、无水乙醇、石油醚和乙酸乙酯制备4种不同溶剂提取物。通过建立3T3-L1前脂肪细胞胰岛素抵抗模型，评价各提取物的降糖活性。再利用α-淀粉、葡萄糖苷酶抑制活性实验，追踪并分离纯化提取物中降糖组分，后进行物质鉴定。其中，CCK-8细胞毒性评价结果表明，4种溶剂提取物对3T3-L1细胞在质量浓度≤100 μg/mL时均表现出很低的细胞毒性；乙酸乙酯提取物在作用细胞质量浓度为10、20、50 μg/mL均表现出较好的降糖活性；该提取物虽对α-葡萄糖苷酶抑制活性不如水提物，但对α-淀粉酶抑制活性最强。结合细胞实验结果，选用乙酸乙酯提取物进一步分离。经硅胶柱层析分离后得到的F5洗脱物表现出良好的降糖效果，其对α-淀粉酶和α-葡萄糖苷酶抑制率分别为66.08%、98.21%。质谱分析发现F5洗脱物中主要物质是相对分子量分别为132.06和162.07的反式肉桂醛及4-甲氧基肉桂醛。故反式肉桂醛及肉桂醛具有一定的降糖活性，可为肉桂作为降糖膳食补充剂的进一步开发利用提供参考依据。

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.