The Calpain Proteolytic System in Neonatal Hypoxic‐Ischemia a
The Calpain Proteolytic System in Neonatal Hypoxic‐Ischemia a
复制标题
新生儿缺氧缺血中的钙蛋白酶蛋白水解系统
DOI：
--
复制
发表时间：
1997
影响因子：
5.2
通讯作者：
H. Hagberg
中科院分区：
文献类型：
--
作者：
K. Blomgren;A. McRae;Anna Elmered;E. Bona;S. Kawashima;T. Saido;T. Ono;H. Hagberg
新生大鼠遭受短暂的脑缺氧缺血（HI，单侧颈总动脉+7.70%O2闭塞100分钟），并恢复长达14天。钙蛋白酶酪蛋白溶解活性被发现增加在两个半球至少20小时。hypoprotein暴露本身增加的钙蛋白酶的活性，更明显的膜相关的部分，可能通过与细胞成分的相互作用，而HI引入了活性的损失，最有可能通过消耗和蛋白酶的损失。用抗钙蛋白酶抑制蛋白、α-胞衬蛋白、α-胞衬蛋白的150-kDa分解产物（FBDP，钙蛋白酶蛋白水解的标志物）或微管相关蛋白2（MAP-2，树突状神经元损伤的标志物）的抗体对连续组织切片进行染色。脑损伤区域显示MAP-2明显丢失，这清楚地描绘了梗死。FBDP在同侧损伤区和交界区积聚，对侧半球FBDP也出现不太明显的一过性增加，尤其是在白色物质中。对皮质组织的胞质组分（CF）和膜和微粒体组分（MMF）进行Western印迹，并用抗钙蛋白酶、钙蛋白酶抑制剂和α-胞衬蛋白（FBDP）的150-kDa分解产物的抗体染色。钙蛋白酶免疫反应性在损伤过程中双侧CF降低（对照组的62-68%），并在早期恢复过程中保持显著降低，而MMF无显著变化。钙蛋白酶的这种易位与同侧HI半球中FBDP的出现相一致，从损伤后立即直到至少1天的恢复（对照的204-292%）显示出显著更高的FBDP水平。在对侧，未受损的半球，尽管易位的钙蛋白酶在两个半球，钙蛋白酶激活的先决条件，FBDP没有显着的变化。这种差异可能与内源性抑制剂calpastatin的变化有关。钙蛋白酶抑制蛋白被发现减少HI期间和后不久，在同侧，但不是对侧，半球。钙蛋白酶抑制蛋白的抑制活性也倾向于减少HI后，表明钙蛋白酶抑制蛋白的减少可能是必要的广泛的钙蛋白酶激活发生。损伤后48小时，HI半球中m-钙蛋白酶的mRNA增加（167%，p < 0.001），此时蛋白质也增加。总之，我们的研究结果表明，钙蛋白酶在HI和HI后再灌注的早期阶段被激活，神经元死亡之前。
Neonatal rats were subjected to transient cerebral hypoxic-ischemia (HI, unilateral occlusion of the common carotid artery +7.70% O2 for 100 min) and allowed to recover for up to 14 days. Calpain caseinolytic activity was found to increase in both hemispheres for at least 20 hr. Hypoxic exposure per se increased the activity of calpains, more pronounced in a membrane-associated fraction, probably through interaction with cellular components, whereas HI introduced a loss of activity, most likely through consumption and loss of proteases. Consecutive tissue sections were stained with antibodies against calpastatin, alpha-fodrin, the 150-kDa breakdown product of alpha-fodrin (FBDP, marker of calpain proteolysis) or microtubule-associated protein 2 (MAP-2, marker of dendrosomatic neuronal injury). Areas with brain injury displayed a distinct loss of MAP-2, which clearly delineated the infarct. FBDP accumulated in injured and borderline regions ipsilaterally, and a less conspicuous, transient increase in FBDP also occurred in the contralateral hemisphere, especially in the white matter. The cytosolic fraction (CF) and the membrane and microsomal fraction (MMF) of cortical tissue were subjected to Western blotting and stained with antibodies against calpain, calpastatin and the 150-kDa breakdown product of alpha-fodrin (FBDP). Calpain immunoreactivity decreased bilaterally in the CF during the insult (62-68% of controls) and remained significantly lower during early recovery, whereas the MMF showed no significant changes. This translocation of calpains coincided with the appearance of FBDP in the ipsilateral, HI hemisphere, displaying a significantly higher level of FBDP from immediately after the insult until at least 1 day of recovery (204-292% of controls). No significant changes in FBDP were found in the contralateral, undamaged hemisphere, despite translocation of calpains in both hemispheres, a prerequisite for calpain activation. This discrepancy may be related to changes in the endogenous inhibitor, calpastatin. Calpastatin protein was found to decrease during and shortly after HI in the ipsilateral, but not the contralateral, hemisphere. The inhibitory activity of calpastatin also tended to decrease after HI, indicating that a reduction of calpastatin may be necessary for extensive calpain activation to occur. The mRNA of m-calpain increased in the HI hemisphere 48 hr after the insult (167%, p < 0.001), a time point when the protein was also increased. In summary, our findings indicate that calpains are activated during HI and in the early phase of reperfusion after HI, preceding neuronal death.
登录
查看更多内容
DOI：
10.1159/000133612
发表时间：
1994
期刊：
Cytogenetics and cell genetics
影响因子：
--
作者：
S. Bohlander;R. Espinosa;A. Fernald;J. Rowley;M. Beau;M. Diaz
通讯作者：
S. Bohlander;R. Espinosa;A. Fernald;J. Rowley;M. Beau;M. Diaz
脑蛋白：钙蛋白酶 I（一种内源性钙激活蛋白酶）的底物。
DOI：
10.1073/pnas.81.11.3572
发表时间：
1984
影响因子：
11.1
作者：
Siman,R;Baudry,M;Lynch,G
通讯作者：
Lynch,G
DOI：
10.1159/000244036
发表时间：
1994
期刊：
Biology of the neonate
影响因子：
--
作者：
J. Towfighi;C. Housman;R. Vannucci;D. Heitjan
通讯作者：
J. Towfighi;C. Housman;R. Vannucci;D. Heitjan
DOI：
10.1073/pnas.88.16.7233
发表时间：
1991-08-01
影响因子：
11.1
作者：
LEE, KS;FRANK, S;LYNCH, G
通讯作者：
LYNCH, G
m-Calpain 需要 DNA 在低钙浓度下对核蛋白发挥活性。
DOI：
--
发表时间：
1993
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Mellgren,RL;Song,K;Mericle,MT
通讯作者：
Mericle,MT