Szabados E, Literati-Nagy P, Farkas B, Sumegi B
Department of Biochemistry, University Medical School Pecs, Pecs, Hungary.
Biochem Pharmacol. 2000 Apr 15;59(8):937-45. doi: 10.1016/s0006-2952(99)00418-9.
The protective effect of O-(3-piperidino-2-hydroxy-1-propyl)nicotinic amidoxime (BGP-15) against ischemia-reperfusion-induced injury was studied in the Langendorff heart perfusion system. To understand the molecular mechanism of the cardioprotection, the effect of BGP-15 on ischemic-reperfusion-induced reactive oxygen species (ROS) formation, lipid peroxidation single-strand DNA break formation, NAD(+) catabolism, and endogenous ADP-ribosylation reactions were investigated. These studies showed that BGP-15 significantly decreased leakage of lactate dehydrogenase, creatine kinase, and aspartate aminotransferase in reperfused hearts, and reduced the rate of NAD(+) catabolism. In addition, BGP-15 dramatically decreased the ischemia-reperfusion-induced self-ADP-ribosylation of nuclear poly(ADP-ribose) polymerase(PARP) and the mono-ADP-ribosylation of an endoplasmic reticulum chaperone GRP78. These data raise the possibility that BGP-15 may have a direct inhibitory effect on PARP. This hypothesis was tested on isolated enzyme, and kinetic analysis showed a mixed-type (noncompetitive) inhibition with a K(i) = 57 +/- 6 microM. Furthermore, BGP-15 decreased levels of ROS, lipid peroxidation, and single-strand DNA breaks in reperfused hearts. These data suggest that PARP may be an important molecular target of BGP-15 and that BGP-15 decreases ROS levels and cell injury during ischemia-reperfusion in the heart by inhibiting PARP activity.
在Langendorff心脏灌注系统中研究了O-(3-哌啶基-2-羟基-1-丙基)烟酰胺肟（BGP-15）对缺血再灌注诱导损伤的保护作用。为了解心脏保护的分子机制，研究了BGP-15对缺血再灌注诱导的活性氧（ROS）形成、脂质过氧化、单链DNA断裂形成、NAD(+)分解代谢和内源性ADP-核糖基化反应的影响。这些研究表明，BGP-15显著降低了再灌注心脏中乳酸脱氢酶、肌酸激酶和天冬氨酸转氨酶的泄漏，并降低了NAD(+)分解代谢率。此外，BGP-15显著降低了缺血再灌注诱导的核多聚（ADP-核糖）聚合酶（PARP）的自身ADP-核糖基化以及内质网伴侣GRP78的单ADP-核糖基化。这些数据增加了BGP-15可能对PARP有直接抑制作用的可能性。在分离的酶上对该假设进行了测试，动力学分析显示为混合型（非竞争性）抑制，K(i)=57±6 microM。此外，BGP-15降低了再灌注心脏中ROS、脂质过氧化和单链DNA断裂的水平。这些数据表明PARP可能是BGP-15的一个重要分子靶点，并且BGP-15通过抑制PARP活性降低心脏缺血再灌注期间的ROS水平和细胞损伤。
