蜂胶的神经保护作用及成分研究

The Neuroprotective Effects of Propolis and Its Ingredients

目的:探讨蜂胶对氧糖剥夺/再灌注(OGD/R)致损N2a细胞的神经保护作用。方法:用体积分数70%的乙醇提取蜂胶,浓缩的乙醇浸膏依次用石油醚、二氯甲烷、乙酸乙酯和丙酮萃取,检测各萃取组分总酚、黄酮/醇、二氢黄酮/醇的含量;将N2a细胞随机分为正常组、OGD/R组、阳性对照组、石油醚萃取物组、二氯甲烷萃取物组、乙酸乙酯萃取物组及丙酮萃取物组,采用CCK-8法检测对细胞存活率的影响,并以吉姆萨染色法检测细胞凋亡情况。结果:不同萃取物组分中,二氯甲烷组分黄酮和二氢黄酮含量最高,分别达到15%和19%,其对受损N2a细胞保护作用也最强;乙酸乙酯组分的总酚含量最高,达到58%,也具有很好的神经保护作用。结论 :通过总酚、黄酮、二氢黄酮含量与受损N2a细胞保护作用的比较,发现神经保护作用与总酚、黄酮、二氢黄酮含量呈正相关,由此判断蜂胶提取物的神经保护作用成分主要为黄酮和二氢黄酮类成分。总酚中非黄酮类酚性成分也有神经保护作用。蜂胶提取物中多酚类物质含量很高,具有开发意义。

Objective： To investigate the neuroprotective effects（and the underlying mechanism） of propolis against the neuronal damage induced by oxygen-glucose deprivation/reoxygenation（OGD/R） in mouse neuroblastoma N2 a cells.Methods： Propolis was extracted with 70% alcohol and the combined alcohol extracts were concentrated under vacuum drying. The resultant residue was partitioned in petroleum ether,dichloromethane,ethyl acetate and acetone. Total phenolic, flavone and flavanone contents in the four samples were determined. N2 a cells were randomly divided into six groups： normal control group, OGD/R group, Ligustrazine group, petroleum ether extraction group, dichloromethane extraction group, ethyl acetate extraction group and acetone extraction group. The neurons survival rate was measured by colorimetric assay（CCK-8 kit）. Leagene Giemsa staining was used to observe the morphology of apoptotic neurons. Results： The results indicated that among the samples, the dichloromethane-soluble fraction showed the highest flavone and flavanone content, and the strongest neuroprotective effects. The ethyl acetate-soluble fraction showed the highest total phenolic content, 58%, and the neuroprotective effect against OGD/R-induced injury. Conclusion： A positive correlation between total phenolic content and neuroprotective effects was observed for all the samples. This indicates that polypehnolics are mainly responsible for their neuroprotective effects. This study demonstrates that the propolis extract has a high exploitation potential.