植物性荷爾蒙對大鼠腦下腺垂體腫瘤細胞多樣性的影響   全文下載

Diverse Effects of Phytoestrogen Biochanin A on Rat Pituitary Tumor Cells

結構類似雌激素的biochanin A存在於多種植物，包含豆科如黃豆等食用作物中，被認為具有類似雌激素的生理功能。近年來流行病學研究發現，攝食富含biochanin A的食物和人類發生與荷爾蒙相關之癌症的機率有負相關性。在本研究中，我們對biochanin A如何影響一受雌激素調控之腦下腺垂體細胞株GH3的生長和基因表現進行分析，實驗結果顯示生理可達濃度的biochanin A對此細胞的生長具有抑制的能力。細胞中雌激素受器（estrogen receptor）和一雌激素標的基因，助孕酮受器（progesterone gene）的mRNA量，皆因biochanin A的處理而降低，而且此現象會被同時添加的抗雌激素劑，ICI182,780所拮抗，但另一雌激素標的基因，泌乳素（prolactin）基因的mRNA和蛋白質量則不受到biochanin A的影響。這些實驗結果指出在生理可達的biochanin A濃度下，biochanin A可抑制腦下腺垂體細胞的生長，而且biochanin A對雌激素相關基因的表現，具有基因專一性的影響。"

Biochanin A, a nonsteroidal estrogen present in plants, has been suggested in epidemiological studies to be associated with a reduced risk of hormone-related cancers. In this study, we examined the effects of biochanin A on the cell growth and gene expression of an estrogen-responsive pituitary cell line GH3. Results showed that biochanin A inhibited growth of GH3 cells in a dose-dependent manner and at physiologically relevant concentrations. At concentrations of 1 and 5 μg/mL, inhibition of cell growth was observed. The gene expressions of estrogen receptor (ER) mRNA and an estrogen responsive gene, the progesterone receptor (PR), were downregulated by the biochanin A treatment. In addition, co-administration of antiestrogen ICI182,780 blocked this biochanin A induced down-regulation of the ER and PR mRNA level. However, the expression level of rat prolactin (rPRL) gene, one of the typical estrogen responsive genes, was not regulated by biochanin A. These results indicated that biochanin A at physiologically achieveable concentrations was able to inhibit cell growth of estrogen-responsive rat pituitary cells. In addition, dietary-derived biochanin A compounds exhibit diverse estrogenic and antiestrogenic effects on estrogen-related gene expression, suggesting gene-specific regulation. 結構類似雌激素的biochanin A存在於多種植物，包含豆科如黃豆等食用作物中，被認為具有類似雌激素的生理功能。近年來流行病學研究發現，攝食富含biochanin A的食物和人類發生與荷爾蒙相關之癌症的機率有負相關性。在本研究中，我們對biochanin A如何影響一受雌激素調控之腦下腺垂體細胞株GH3的生長和基因表現進行分析，實驗結果顯示生理可達濃度的biochanin A對此細胞的生長具有抑制的能力。細胞中雌激素受器（estrogen receptor）和一雌激素標的基因，助孕酮受器（progesterone gene）的mRNA量，皆因biochanin A的處理而降低，而且此現象會被同時添加的抗雌激素劑，ICI182,780所拮抗，但另一雌激素標的基因，泌乳素（prolactin）基因的mRNA和蛋白質量則不受到biochanin A的影響。這些實驗結果指出在生理可達的biochanin A濃度下，biochanin A可抑制腦下腺垂體細胞的生長，而且biochanin A對雌激素相關基因的表現，具有基因專一性的影響。