Draganova-Filipova Milena N, Georgieva Milena G, Peycheva Ekaterina N, Miloshev George A, Sarafian Victoria S, Peychev Lyudmil P
Department of Biology, Medical University, Plovdiv, Bulgaria.
Folia Med (Plovdiv). 2008;50(1):53-9.
The mechanisms of action of propolis can be studied in detail by comparing the effects of propolis and the effects of its constituent components.
To clarify and compare the effects of Bulgarian propolis and caffeic acid phenethyl ester (CAPE, a chemically synthesized component of propolis)--by using a set of cellular, molecular-biological and immunological techniques.
The McCoy-Plovdiv cell line was treated with propolis and CAPE in increasing concentrations (0.01, 0.1, 1.0, 10 mg/L, and 2.5, 4, 8, 16 mg/L, respectively). The expression of the proliferating cell nuclear antigen (PCNA) and the tumour-suppressor protein p53 was studied immunocytochemically. Apoptosis was measured using a highly sensitive microgel electrophoresis technique (comet assay).
The results of the study showed corresponding changes in the expression of the examined proliferative antigens. PCNA was detected in all examined concentrations of the tested substances the expression being dose-dependent. Molecule localization changed from the nucleus to the cytoplasm. Treatment with CAPE brought about gradual attenuation of PCNA expression. High propolis concentrations induced increased synthesis of p53. No p53 expression was found when cells were treated with CAPE. The studied substances in their highest concentrations (10 mg/L propolis and 16 mg/L CAPE) had a cytotoxic effect. The comet assay showed DNA degradation kinetics characteristic for apoptosis.
The present study demonstrates that high concentrations of propolis and CAPE cause apoptosis-induced cell death in McCoy-Plovdiv cells.
通过比较蜂胶及其成分的作用效果，可以详细研究蜂胶的作用机制。
运用一系列细胞、分子生物学和免疫学技术，阐明并比较保加利亚蜂胶和咖啡酸苯乙酯（CAPE，蜂胶的一种化学合成成分）的作用效果。
用浓度递增的蜂胶和CAPE（分别为0.01、0.1、1.0、10mg/L以及2.5、4、8、16mg/L）处理麦科伊-普罗夫迪夫细胞系。采用免疫细胞化学方法研究增殖细胞核抗原（PCNA）和肿瘤抑制蛋白p53的表达。使用高灵敏度微凝胶电泳技术（彗星试验）检测细胞凋亡情况。
研究结果显示，所检测的增殖抗原的表达发生了相应变化。在所有检测浓度的受试物质中均检测到PCNA，其表达呈剂量依赖性。分子定位从细胞核转移至细胞质。CAPE处理导致PCNA表达逐渐减弱。高浓度蜂胶诱导p53合成增加。用CAPE处理细胞时未发现p53表达。所研究物质的最高浓度（10mg/L蜂胶和16mg/L CAPE）具有细胞毒性作用。彗星试验显示出细胞凋亡特有的DNA降解动力学特征。
本研究表明，高浓度的蜂胶和CAPE可导致麦科伊-普罗夫迪夫细胞发生凋亡诱导的细胞死亡。
