Use of Inosine Monophosphate Dehydrogenase Activity Assay to Determine the Specificity of PARP-1 Inhibitors.
Use of Inosine Monophosphate Dehydrogenase Activity Assay to Determine the Specificity of PARP-1 Inhibitors.
复制标题
使用肌苷单磷酸脱氢酶活性测定确定 PARP-1 抑制剂的特异性。
DOI：
10.1007/978-1-4939-6993-7_22
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Ji,Yingbiao
中科院分区：
文献类型：
--
作者：
Anthony,Sajitha;Peterson,JeffreyR;Ji,Yingbiao
肌苷单磷酸脱氢酶（IMPDH）是一种参与嘌呤核苷酸生物合成的限速酶。它负责催化单磷酸肌苷（IMP）氧化成单磷酸黄嘌呤（XMP）。同时，辅因子NAD+被还原为NADH。聚（adp -核糖）聚合酶1 （PARP-1）也利用NAD+作为底物合成聚（adp -核糖）。研究表明，抑制PARP-1活性是一种有效的癌症治疗方法。然而，大多数PARP-1抑制剂，包括奥拉帕尼，都是作为NAD+类似物开发的。因此，这些抑制剂可能会干扰其他依赖NAD+的途径，如参与从头嘌呤代谢的途径。在本章中，我们描述了一种利用产物NADH的自身荧光定量测量IMPDH活性的方法。我们用这种方法分析了奥拉帕尼和非nad +样PARP-1抑制剂（5F02）对IMPDH活性的影响。我们发现，与5F02不同，奥拉帕尼以剂量依赖性的方式显著抑制IMPDH活性。我们的结果表明，IMPDH抑制是奥拉帕尼治疗的脱靶效应。这种影响的后果应在未来的临床研究中加以解决。
Inosine monophosphate dehydrogenase (IMPDH) is a rate-limiting enzyme involved in purine nucleotide biosynthesis. It is responsible for catalyzing the oxidation of inosine monophosphate (IMP) into xanthosine monophosphate (XMP). Concurrently, the cofactor NAD+is reduced to NADH. Poly(ADP-ribose) polymerase 1 (PARP-1) also utilizes NAD+as a substrate to synthesize poly(ADP-ribose). It has been demonstrated that inhibition of PARP-1 activity can be an effective cancer therapeutic. However, most PARP-1 inhibitors, including olaparib, were developed as NAD+analogs. Therefore, these inhibitors likely interfere with other NAD+-dependent pathways such as the one involved in de novo purine metabolism. In this chapter, we describe a method to quantitatively measure IMPDH activity by taking advantage of the autofluorescence of the product NADH. We use this method to analyze the effects of olaparib and non-NAD+-like PARP-1 inhibitor (5F02) on IMPDH activity. We found that olaparib, unlike 5F02, significantly inhibits IMPDH activity in a dose-dependent manner. Our results suggest that IMPDH inhibition is an off-target effect of olaparib treatment. The consequences of this effect should be addressed by future clinical studies.
影响因子：
4
作者：
Ji, Yingbiao;Tulin, Alexei V.
通讯作者：
Tulin, Alexei V.