Preobrazhenskaya M N, Bukhman V M, Korolev A M, Efimov S A
Institute of New Antibiotics, Russian Academy of Medical Sciences, Moscow.
Pharmacol Ther. 1993 Nov;60(2):301-13. doi: 10.1016/0163-7258(93)90012-3.
Searches for the natural compounds that determine the anticarcinogenic properties of a cruciferous-vegetable diet, revealed the products of alkaloid glucobrassicin biotransformations; among these, ascorbigen, an indole-containing derivative of L-ascorbic acid, was found to be the most abundant. Study of chemical properties of ascorbigen showed that it is capable of different transformations in acidic (including gastric juice) and slightly alkaline (including blood) media. The stable and unstable products of ascorbigen transformation determine the biological properties of the compound. The most important product of ascorbigen transformation in gastric juice is 5,11-dihydroindolo[3,2-b]-carbazole, with a binding affinity to the Ah receptor only 3.7 x 10(-2) lower than that of tetrachlorodibenzodioxin. This compound may be responsible for modifying P450 enzyme activities. Ascorbigen and its analogs are available synthetically. Their biological evaluation showed that some of the compounds of these series are immunomodulators. The most active is N-methylascorbigen, which demonstrates therapeutic effects (inhibition of tumor growth, protection of animals from bacterial and viral infections). The immunomodulatory activity of natural ascorbigen may be an additional factor of importance for the anticarcinogenic properties of a cruciferous-vegetable diet.
对决定十字花科蔬菜饮食抗癌特性的天然化合物的研究，揭示了生物碱硫代葡萄糖苷生物转化的产物；其中，抗坏血酸生成素，一种L-抗坏血酸的含吲哚衍生物，被发现是含量最丰富的。对抗坏血酸生成素化学性质的研究表明，它在酸性（包括胃液）和微碱性（包括血液）介质中能够发生不同的转化。抗坏血酸生成素转化的稳定和不稳定产物决定了该化合物的生物学特性。抗坏血酸生成素在胃液中转化的最重要产物是5,11-二氢吲哚并[3,2-b]咔唑，其与芳烃受体的结合亲和力仅比四氯二苯并二恶英低3.7×10⁻²。这种化合物可能负责调节P450酶的活性。抗坏血酸生成素及其类似物可以通过合成获得。它们的生物学评估表明，这些系列中的一些化合物是免疫调节剂。最具活性的是N-甲基抗坏血酸生成素，它具有治疗作用（抑制肿瘤生长，保护动物免受细菌和病毒感染）。天然抗坏血酸生成素的免疫调节活性可能是十字花科蔬菜饮食抗癌特性的另一个重要因素。
