Dashwood R H, Fong A T, Hendricks J D, Bailey G S
Department of Food Science and Technology, Oregon State University, Corvallis 97331.
Basic Life Sci. 1990;52:361-5. doi: 10.1007/978-1-4615-9561-8_33.
Indole-3-carbinol (I3C), a natural compound from cruciferous vegetables, inhibits aflatoxin B1 (AFB1) carcinogenesis in trout when administered prior to and during carcinogen exposure, but also promotes it in the same species when given after AFB1 initiation. To provide quantitative potency information for these opposing activities, detailed tumor dose-response studies were performed with AFB1 (10-400 ppb) and I3C (0-4,000 ppm). In a plot of (logit) percent tumor response vs log AFB1 exposure, the results generated a series of parallel AFB1 dose-response curves. Increasing I3C doses displaced these curves, respectively, toward higher and lower AFB1 doses in the inhibition and promotion studies. Similar potencies were observed over the dose range 0-1,500 ppm I3C; the 50% promotion and inhibition (P50 and I50) values were 1,000 vs 1,400 ppm I3C, respectively. Differences in the protocols used in the two studies suggest that the inhibitory activity of I3C is more likely to supersede promotion under human exposure conditions.
吲哚 - 3 - 甲醇（I3C）是一种源自十字花科蔬菜的天然化合物，在致癌物暴露之前及期间给予鳟鱼时，它可抑制黄曲霉毒素B1（AFB1）致癌作用，但在AFB1启动之后给予相同物种时，它也会促进致癌作用。为了提供这些相反作用的定量效力信息，使用AFB1（10 - 400 ppb）和I3C（0 - 4000 ppm）进行了详细的肿瘤剂量反应研究。在（对数单位）肿瘤反应百分比对AFB1暴露对数的图中，结果产生了一系列平行的AFB1剂量反应曲线。在抑制和促进研究中，增加I3C剂量分别使这些曲线向更高和更低的AFB1剂量移动。在0 - 1500 ppm I3C剂量范围内观察到相似的效力；50%促进和抑制（P50和I50）值分别为1000 ppm和1400 ppm I3C。两项研究中使用的方案差异表明，在人类暴露条件下，I3C的抑制活性更有可能取代促进作用。
