Yasui Yumiko, Miyamoto Shingo, Kim Mihye, Kohno Hiroyuki, Sugie Shigeyuki, Tanaka Takuji
Department of Oncologic Pathology, Kanazawa Medical University, Ishikawa, Japan.
Oncol Rep. 2008 Sep;20(3):493-9.
We investigated the effects of the two fractions, aqueous (AEP) and ethanolic extracts of propolis (EEP) of the Brazilian propolis on azoxymethane (AOM)-induced aberrant crypt foci (ACF). Male Wistar Hannover (GALAS) rats were administered two weekly subcutaneous injections of AOM (20 mg/kg bw) and fed with diets mixed with AEP (100, 500 and 1,000 ppm) or EEP (500 and 1,000 ppm) for 4 weeks, starting one week before the first dosing of AOM. The modifying effects of the test extracts on ACF formation were assessed by counting the incidence and multiplicity of ACF at week 4. Proliferation cell nuclear antigen (PCNA)-labeling nuclei and apoptotic index were also immunohistochemically determined. Dietary supplementation with AEP and EEP significantly reduced the multiplicity of ACF with the effect of EEP being more potent than AEP. In the ACF and their surrounding non-lesional crypts, significantly lowered cell proliferation was observed in the rats, administered with AOM, and the extracts, while neither fraction affected the apoptotic index. Our findings suggest that AEP and EEP possess a chemopreventive ability in the early phase of colon carcinogenesis through the modulation of cell proliferation.
我们研究了巴西蜂胶的水提取物（AEP）和乙醇提取物（EEP）这两种组分对氧化偶氮甲烷（AOM）诱导的异常隐窝灶（ACF）的影响。雄性Wistar Hannover（GALAS）大鼠每周皮下注射两次AOM（20 mg/kg体重），并从首次给予AOM前一周开始，用含有AEP（100、500和1000 ppm）或EEP（500和1000 ppm）的饲料喂养4周。在第4周时，通过计数ACF的发生率和多灶性来评估受试提取物对ACF形成的改善作用。还通过免疫组织化学方法测定增殖细胞核抗原（PCNA）标记的细胞核和凋亡指数。膳食补充AEP和EEP可显著降低ACF的多灶性，EEP的效果比AEP更强。在ACF及其周围的非病变隐窝中，给予AOM和提取物的大鼠细胞增殖显著降低，而两种组分均未影响凋亡指数。我们的研究结果表明，AEP和EEP通过调节细胞增殖在结肠癌发生的早期阶段具有化学预防能力。
