Nitroprusside induces cardiomyocyte death: interaction with hydrogen peroxide

被引:51
作者
Rabkin, SW [1 ]
Kong, JY [1 ]
机构
[1] Univ British Columbia, Dept Med, Div Cardiol, Vancouver, BC V5Z 3J5, Canada
来源
AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY | 2000年 / 279卷 / 06期
关键词
apoptosis;
D O I
10.1152/ajpheart.2000.279.6.H3089
中图分类号
R5 [内科学];
学科分类号
1002 ; 100201 ;
摘要
We examined the hypothesis that sodium nitroprusside (SNP) produces cell death in cardiomyocytes through generation of H2O2. Embryonic chick cardiomyocytes in culture were treated with SNP, and cell viability was assessed by trypan blue, MTT assay, and fluorescent activated cell sorting (FACS) analysis. SNP for 24 h induced a significant (P< 0.001) dose-dependent loss of cell viability. On MTT assay, the half-maximal effective concentration was 0.53 mM (confidence interval 0.45-0.59 mM). SNP-treated cardiomyocytes displayed characteristic microscopic features of apoptosis: reduced cell size, nuclear disintegration, and membrane bleb formation. FACS analysis demonstrated SNP-induced apoptosis as well as cell changes consistent with necrosis. The proportion of cells with nuclear changes of apoptosis, identified by propidium iodide (PI) staining of permeabilized cells, increased significantly (P< 0.05) after 0.5 mM SNP for 24 h. The proportion of apoptotic cells, characterized by dual staining of intact cardiomyocytes with fluorescein diacetate and PI, was significantly (P< 0.05) increased after treatment with 0.5 mM SNP for 24 h. SNP metabolism and NO production was suggested by the significant (P< 0.05) increase in nitrite generation in the media with 0.5 mM SNP compared with control. SNP-mediated H2O2 production was implicated in the mechanism of SNP-induced cell death. First, SNP produced a significant (P< 0.05) increase in H2O2 detected in the media after 6 or 24 h of SNP treatment. Second, catalase completely blocked the reduction of cell viability induced by 0.1 mM SNP and significantly (P< 0.05) blunted the effect of 0.5 mM SNP. In contrast, the iron chelator deferoxamine did not alter SNP-induced loss of cell viability. FACS analysis showed that the combination of low concentrations of H2O2 (10(-8) M) that did not alter cell viability augmented SNP-induced apoptosis. In contrast, the amount of necrotic cell death was unchanged by the combination of H2O2 and SNP. H2O2 plus SNP produced a dramatic alteration in cell structure with greater membrane bleb formation, shrunken cells, and more intense cytosolic acridine orange staining and nuclear fragmentation than either agent alone. These data indicate the vulnerability of cardiomyocytes to SNP and suggest the involvement of H2O2 in the pathogenesis of SNP-induced cardiomyocyte cell death. Establishing apoptosis as a component of the type of cell death induced by SNP permitted the recognition that SNP-induced apoptosis was increased by chronic treatment with low (subtoxic) concentrations of H2O2.
引用
收藏
页码:H3089 / H3100
页数:12
相关论文
共 48 条
  • [1] Calcium channel blockers induce thymic apoptosis in vivo in rats
    Balakumaran, A
    Campbell, GA
    Moslen, MT
    [J]. TOXICOLOGY AND APPLIED PHARMACOLOGY, 1996, 139 (01) : 122 - 127
  • [2] Beckman JS, 1996, AM J PHYSIOL-CELL PH, V271, pC1424
  • [3] Basic and clinical aspects of myocardial stunning
    Bolli, R
    [J]. PROGRESS IN CARDIOVASCULAR DISEASES, 1998, 40 (06) : 477 - 516
  • [4] EVIDENCE OF DIRECT TOXIC EFFECTS OF FREE-RADICALS ON THE MYOCARDIUM
    BURTON, KP
    [J]. FREE RADICAL BIOLOGY AND MEDICINE, 1988, 4 (01) : 15 - 24
  • [5] HYDROGEN-PEROXIDE CYTOTOXICITY IN CULTURED CARDIAC MYOCYTES IS IRON-DEPENDENT
    BYLER, RM
    SHERMAN, NA
    WALLNER, JS
    HORWITZ, LD
    [J]. AMERICAN JOURNAL OF PHYSIOLOGY, 1994, 266 (01): : H121 - H127
  • [6] Chen Y, 1997, P SOC EXP BIOL MED, V216, P112
  • [7] INTERLEUKIN-1-BETA SUPPRESSES APOPTOSIS IN RAT OVARIAN FOLLICLES BY INCREASING NITRIC-OXIDE PRODUCTION
    CHUN, SY
    EISENHAUER, KM
    KUBO, M
    HSUEH, AJW
    [J]. ENDOCRINOLOGY, 1995, 136 (07) : 3120 - 3127
  • [8] CUI SJ, 1994, CANCER RES, V54, P2462
  • [9] OXIDATIVE STRESS DURING REPERFUSION OF HUMAN HEARTS - POTENTIAL SOURCES OF OXYGEN-FREE RADICALS
    CURELLO, S
    CECONI, C
    DEGIULI, F
    PANZALI, AF
    MILANESI, B
    CALARCO, M
    PARDINI, A
    MARZOLLO, P
    ALFIERI, O
    MESSINEO, F
    FERRARI, R
    [J]. CARDIOVASCULAR RESEARCH, 1995, 29 (01) : 118 - 125
  • [10] Dimmeler S, 1997, CIRC RES, V81, P970