ALCOHOL EFFECT OF AZT PHOSPHORYLATION REQUIRED FOR ACTIVATION OF AZT

甲氧西林的化疗药物3‘-叠氮-2’，3‘-二脱氧胸苷 HIV疾病患者的选择，需要细胞激活 由一系列细胞激酶催化生成三磷酸形式(AZT- TP)具有抗病毒活性。级联中的两个速率限制步骤 已确定激活：1)胸苷激酶，这种酶 将AZT转化为其单磷酸(AZT-MP)，以及2)胸苷酸激酶， 将AZT转化为二磷酸的酶(AZT-DP)。早期的研究表明 研究表明，AZT的抗病毒活性可以通过缺陷在 这些激酶中任何一种的表达。此外，AZT疗法是 常伴有严重的造血毒性，导致贫血 还有白细胞减少症。目前，还没有关于酒精如何 消耗可能会改变AZT向其活性形式或修饰的转化 该药物对感染HIV-1病毒的个体的毒性作用。的确有 有证据表明酒精有能力下调 胸苷激酶以及抑制造血祖细胞的生长 在文化上。我们的假设是酒精在HIV-1存在的情况下 蛋白质(S)将1)下调胸腺嘧啶核苷-胸腺苷的表达 激活和抑制AZT的活性形式；2) 增强AZT对造血祖细胞的毒性作用。这 该提案将在表达完整基因的转基因小鼠身上测试这一假设。 长度为TAT(TAT/86)的蛋白，以及在小鼠(HIV小鼠)中表达数字 HIV编码蛋白，并有6个特定的目标。具体目标1，测试 酒精抑制胸腺嘧啶核苷活性的预测 小鼠骨髓、胸腺和肝脏组织中的激酶。由于AZT是 已知会减弱自身的磷酸化，在特定的目标2中，我们将 评估酒精对AZT处理的小鼠的影响。为了测试 预测胸腺嘧啶核苷-胸苷酸激酶的抑制与 降低AZT的磷酸化。在具体目标3中，我们将衡量 体外实验中小鼠组织磷酸化AZT的能力。在……里面 具体目标4，我们将检验这一预测的压制 在AIMS 1和2中看到的胸苷激酶活性是可比性的结果 其信使核糖核酸合成减少。在具体的目标5和6中，我们将测试 关于饮酒对身体健康有抑制作用的预测 骨髓祖细胞的增殖，并进一步增强 AZT的抑制作用。建议的研究结果将会 对酒精在艾滋病毒中的辅助因素作用提供新的见解 发病机制是通过降低抗病毒活性和增加 AZT及相关药物的造血毒性。

3'-Azido-2',3'-dideoxythymidine (AZT), the chemotherapeutic agent of first choice for patients with HIV disease, requires cellular activation catalyzed by a series of cellular kinases to the triphosphate form (AZT- TP) for antiviral activity. Two rate-limiting steps in the cascade of activation have been identified: 1) thymidine kinase, the enzyme that converts AZT to its monophosphate (AZT-MP), and 2) thymidylate kinase, the enzyme that converts AZT to its diphosphate (AZT-DP). Earlier studies have shown that the antiviral activity of AZT can be reduced through defect in the expression of any one of these kinases. In addition, AZT therapy is regularly accompanied by severe hematopoietic toxicity leading to anemia and leukopenia. Currently, there is no information on how alcohol consumption might alter the conversion of AZT to its active form or modify the toxic effects of the drug in HIV-1 affected individuals. There is evidence that alcohol has the ability to down-regulate the expression of thymidine kinase as well as impair the growth of hematopoietic progenitors in culture. It is our hypothesis that alcohol in the presence of HIV-1 protein(s) will 1) down-regulate the expression of thymidine-thymidylate kinases and inhibit the activation of AZT to its active form; and 2) enhance toxic effects of AZT on hematopoietic progenitor cells. This proposal will test the hypothesis in transgenic mice that express full- length Tat (Tat/86) protein, and in mice (HIV mice) that express a number of HIV-encoded proteins, and has 6 Specific Aims. Specific Aim 1, to test the prediction that alcohol suppresses activities of thymidine-thymidylate kinases in bone marrow, thymus and liver tissues of mice. Since AZT is known to diminish its own phosphorylation, in Specific Aim 2, we will assess the effects of alcohol in AZT-treated mice. In order to test the prediction that suppression of thymidine-thymidylate kinases is linked to decreased AZT phosphorylation. In Specific Aim 3, we will measure the capacity of the mouse tissues to phosphorylate AZT in in vitro assays. In Specific Aim 4, we will test the prediction that the suppression of thymidine kinase activity seen in Aims 1 and 2 is the result of comparable decreases in its mRNA synthesis. In Specific Aims 5 and 6, we will test the prediction that alcohol consumption has suppressive effect on the proliferation of bone marrow progenitors and further enhances the suppressive effects of AZT. The results of the proposed studied will provide new insights into the co-factor role of alcohol in HIV pathogenesis through decreased antiviral activity and increased hematopoietic toxicity of AZT and related drugs.