大豆異黃酮對DMBA誘發有無卵巢切除雌鼠乳腺腫瘤之延緩效應

The Delayed Tumorgenesis of Soy Isoflavones on 7,12-dimethylbenz(a)anthracene(DMBA)-Induced Mammary Tumors in Female Spague-Dawley(SD) Rats with or without Ovariectomization

陳怡坊(Yi Fang Chen)

指導教授 ： 簡怡雯

臺北醫學大學/公共衛生暨營養學院/保健營養學研究所/碩士(2005年)

摘要

本研究係探討一般飲食添加大豆異黃酮素對DMBA誘發偽手術或卵巢切除雌鼠乳腺腫瘤之延緩效應。以48隻Sprague-Dawley雌鼠為實驗動物模式，於鼠齡7週大時以相當老鼠每公斤體重80毫克之7,12-dimethylbenzvieded anthracene (DMBA)灌食來誘發其乳腺腫瘤之生成，並在誘導後2週隨機分為二大組【偽手術組（S）和卵巢切除組（O）】進行手術。每大組分別餵食三種實驗飲食：C飲食為#5001粉末飼料（SC組和OC組）；S1飲食為#5001粉末飼料每公斤額外添加1g大豆異黃酮素（SS1組和OS1組）；S2飲食為#5001粉末飼料每公斤額外添加2g大豆異黃酮素（SS2組和OS2組）。自鼠齡12週起，每週進行觸診，記錄腫瘤開始出現的時間、大小、位置、及生長狀況，並於DMBA誘導27週後犧牲並進行組織分析。結果發現： SC組和SS2組的腫瘤發生率大於其他組。第34週血漿中雌激素濃度在各大組中皆呈現劑量依賴效應。肝臟中細胞色素P450（CYP）活性測定方面：除了EMD活性外，偽手術組的PROD和EROD活性皆大於卵巢切除組；EMD活性則呈現劑量依賴效應。結果可推論，給予偽手術老鼠每公斤飼料1克大豆異黃酮可降低乳腺腫瘤發生，而給予2克則會促進乳腺腫瘤發生；而卵巢切除老鼠不論給予1克或2克皆可抑制乳腺腫瘤發生。

關鍵字

大豆異黃酮 ； 乳腺腫瘤 ； 卵巢切除 ； 偽手術 ； 細胞色素P450

並列摘要

The aim of this study was to clarify the effects of soy isoflavones on 7,12-dimethylbenz(a)anthracene(DMBA)-induced mammary tumors in sham and ovariectomized female Spague-Dawley (SD) rats. 80 mg /kg body weight DMBA was administrated orally to 48 rats at the age of 7 weeks. Two weeks after DMBA administration, rats were divided into two groups, which were sham-operation and ovariectomy-operation. Each groups was fed three different diets: C diet: #5001 chow diet (SC or OC), S1 diet: #5001 chow diet plus 1g soy isoflavones/kg diet (SS1 or OS1) and S2 diet: #5001 chow diet plus 2g soy isoflavones/kg diet (SS2 or OS2). The numbers and volume of tumors were recorded once a week by palpating rats from the age of 12 weeks. Finally, the rats were sacrificed after 27 weeks of DMBA administration for analysis. The results showed the tumor incidence of SC and SS2 groups were greater than other groups. At the age of 34 weeks, the plasma estradiol concentration of rat showed dose-dependent effects. The liver microsome were analyzed for total cytochrome P450 and isozyme activities：Both EROD activities and PROD activities of sham groups were higher than those of ovariectomy groups except EMD activities. The EMD activities of all groups showed dose-dependent. The results indicated that supplement of 1g isoflavones in diet could decrease tumorgenesis of sham groups, however, supplement of 2g isoflavones in diet could increase tumorgenesis. Both supplement of 1g or 2g isoflavones in diet could inhibit tumorgenesis of ovariectomy groups.

並列關鍵字

soy isoflavones ； mammary tumors ； sham ； ovariectomy ； CYP

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