Glucosamine protects neonatal cardiomyocytes from ischemia-reperfusion injury via increased protein-associated O-GlcNAc
Glucosamine protects neonatal cardiomyocytes from ischemia-reperfusion injury via increased protein-associated O-GlcNAc
复制标题
DOI：
10.1152/ajpcell.00162.2006
复制
发表时间：
2007-01-01
影响因子：
5.5
通讯作者：
Chatham, John C.
中科院分区：
文献类型：
--
作者：
Champattanachai, Voraratt;Marchase, Richard B.;Chatham, John C.
蛋白质O-连接的N-乙酰葡糖胺（O-GlcNAc）水平的增加已被证明可以增加应激后的细胞存活。因此，本研究的目的是确定在分离的新生大鼠心室肌细胞（NRVM）中，蛋白质O-GlcNAc化的增加是否导致缺血再灌注（I/R）后存活率和活力的改善。NRVM暴露于4小时的缺血和16小时的再灌注，细胞活力，坏死，凋亡，和O-GlcNAc水平进行了评估。用葡萄糖胺、高血糖或O-（2-乙酰氨基-2-脱氧-D-吡喃葡萄糖基亚基）-氨基-N-苯基氨基甲酸酯（PUGNAc）（O-GlcNAc酶的抑制剂）处理细胞，与I/R后未处理的细胞相比，显著增加O-GlcNAc水平并改善细胞活力，以及减少坏死和凋亡。O-GlcNAc转移酶抑制剂Alloxan显著降低OGlcNAc水平，加重I/R损伤。高血糖症患者生存率的改善被阿扎胞苷减弱，阿扎胞苷通过己糖胺生物合成途径抑制葡萄糖代谢。与正常葡萄糖条件相比，在没有葡萄糖的情况下的再灌注降低了再灌注时的O-GlcNAc水平，并降低了细胞活力。O-GlcNAc水平与再灌注期间的细胞活力显著相关。葡糖胺和PUGNAc对细胞活力的影响与通过活化T细胞的核因子易位测量的钙调磷酸酶活化降低相关，表明增加的O-GlcNAc水平可减弱I/R诱导的胞质Ca 2+增加。这些数据支持以下概念：导致O-GlcNAc水平增加的代谢途径活化是内源性应激激活反应，并且该反应的增强改善了细胞存活。因此，旨在激活这些途径的策略可能代表诱导心脏保护的新干预措施。
Increased levels of protein O-linked N-acetylglucosamine (O-GlcNAc) have been shown to increase cell survival following stress. Therefore, the goal of this study was to determine whether in isolated neonatal rat ventricular myocytes (NRVMs) an increase in protein O-GlcNAcylation resulted in improved survival and viability following ischemia-reperfusion (I/R). NRVMs were exposed to 4 h of ischemia and 16 h of reperfusion, and cell viability, necrosis, apoptosis, and O-GlcNAc levels were assessed. Treatment of cells with glucosamine, hyperglycemia, or O-(2-acetamido-2-deoxy-D-glucopyranosylidene)-amino-N-phenylcarbamate (PUGNAc), an inhibitor of O-GlcNAcase, significantly increased O-GlcNAc levels and improved cell viability, as well as reducing both necrosis and apoptosis compared with untreated cells following I/R. Alloxan, an inhibitor of O- GlcNAc transferase, markedly reduced OGlcNAc levels and exacerbated I/R injury. The improved survival with hyperglycemia was attenuated by azaserine, which inhibits glucose metabolism via the hexosamine biosynthesis pathway. Reperfusion in the absence of glucose reduced O- GlcNAc levels on reperfusion compared with normal glucose conditions and decreased cell viability. O-GlcNAc levels significantly correlated with cell viability during reperfusion. The effects of glucosamine and PUGNAc on cellular viability were associated with reduced calcineurin activation as measured by translocation of nuclear factor of activated T cells, suggesting that increased O-GlcNAc levels may attenuate I/R induced increase in cytosolic Ca2+. These data support the concept that activation of metabolic pathways leading to an increase in O-GlcNAc levels is an endogenous stress-activated response and that augmentation of this response improves cell survival. Thus strategies designed to activate these pathways may represent novel interventions for inducing cardioprotection.