Moslemi S, Seralini G E
Laboratoire de Biochimie et Biologie Moléculaire, EP CNRS 9, IBBA, Université de Caen, France.
J Enzyme Inhib. 1997 Dec;12(4):241-54. doi: 10.3109/14756369709035817.
In order to approach the detailed structure-function relationships of aromatase, we studied the inhibitory and inactivatory potencies of several steroidal androstenedione analogues (1: 4-hydroxyandrostenedione, 2: 4-acetoxyandrostenedione and 3: 7 alpha-(4'-amino)phenylthio-4-androstene-3, 17-dione) and non-steroidal imidazole derivatives (4: ketoconazole, 5: miconazole and 6: fadrozole) on equine aromatase in placental microsomes, a well established mammalian model. Human placental microsomes and the purified enzyme from equine testis were also used to compare inhibition by 1 and 2. In equine microsomes, all compounds tested exhibited a competitive inhibition, with Ki values of 4.1, 26 and 1.8 nM for 1, 2 and 3, and of 2400, 1.4 and 4 nM for 4, 5, and 6, respectively. The Km for androstenedione, the substrate mainly used in these studies, was 1.8 +/- 0.13 nM. The three non-steroidal derivatives did not inactivate equine aromatase, but 1 and 2 acted as comparable inactivators to a much higher degree than 3. Compound 1 inhibited in a similar manner (89-94%) purified or equine and human microsomal aromatases, whereas 2 inhibited microsomal aromatase more efficiently in the horse than in man (92% and 33% inhibition, respectively). There was only a 40% inhibition with 2 on the purified equine enzyme, which is no more in the natural membrane environment. The comparisons between equine and human microsomal aromatases allow precise functional and structural differences to be observed with these enzymes.
为了深入研究芳香化酶的详细结构 - 功能关系，我们研究了几种甾体雄烯二酮类似物（1：4 - 羟基雄烯二酮，2：4 - 乙酰氧基雄烯二酮，3：7α - （4'-氨基）苯硫基 - 4 - 雄烯 - 3,17 - 二酮）和非甾体咪唑衍生物（4：酮康唑，5：咪康唑，6：法倔唑）对胎盘微粒体中马芳香化酶的抑制和失活效力，胎盘微粒体是一种成熟的哺乳动物模型。人胎盘微粒体和从马睾丸中纯化的酶也被用于比较1和2的抑制作用。在马微粒体中，所有测试化合物均表现出竞争性抑制，1、2和3的Ki值分别为4.1、26和1.8 nM，4、5和6的Ki值分别为2400、1.4和4 nM。这些研究中主要使用的底物雄烯二酮的Km为1.8±0.13 nM。三种非甾体衍生物不会使马芳香化酶失活，但1和2作为失活剂的作用程度比3高得多。化合物1对纯化的或马和人微粒体芳香化酶的抑制方式相似（89 - 94%），而2对马微粒体芳香化酶的抑制效率高于人（分别为92%和33%抑制）。2对纯化的马酶的抑制率仅为40%，在天然膜环境中则更低。马和人微粒体芳香化酶之间的比较使得能够观察到这些酶在功能和结构上的精确差异。
