Overexpression of wild-type heat shock protein 27 and a nonphosphorylatable heat shock protein 27 mutant protects against ischemia/reperfusion injury in a transgenic mouse model
Overexpression of wild-type heat shock protein 27 and a nonphosphorylatable heat shock protein 27 mutant protects against ischemia/reperfusion injury in a transgenic mouse model
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DOI：
10.1161/01.cir.0000148825.99184.50
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发表时间：
2004-12-07
期刊：
影响因子：
37.8
通讯作者：
Dillmann, WH
中科院分区：
文献类型：
--
作者：
Hollander, JM;Martin, JL;Dillmann, WH
小分子热休克蛋白27（hsp 27）在心脏缺血/再灌注损伤时表达增加。小hsp的一个特征是它们能够寡聚化并形成细胞内聚集体。寡聚化模式由蛋白质的磷酸化状态决定，磷酸化状态可能影响它们抵抗细胞应激的能力。方法和结果-我们产生了过表达野生型人hsp 27（hsp 27 tg）蛋白或突变型hsp 27蛋白的转基因（tg）小鼠（mut-hsp 27 tg），其中丝氨酸残基（aa 15、aa 78和aa 82）被丙氨酸残基取代，使得它们不能磷酸化。使用Langendorff灌注模型和心室内球囊，我们使心脏缺血20分钟，然后再灌注1小时。在再灌注过程中，hsp 27 tg和mut-hsp 27 tg组的负压、正压导数和发展压均显著高于对照组（P < 0.01），而hsp 27 tg和mut-hsp 27 tg组之间无显著差异。对照组再灌注时肌酸激酶释放量高于hsp 27 tg和mut-hsp 27 tg组（P < 0.05）。与对照组相比，mut-hsp 27 tg组的丙二醛含量和蛋白质氧化产物含量显著降低（P < 0.05）。hsp 27 tg心脏具有低聚物，大小从小到大，而mut-hsp 27 tg心脏不含小oligors.Conclusions -这些结果表明，在tg小鼠模型中，野生型hsp 27或nonphosphorylatable hsp 27突变体的过度表达同样能够保护心脏免受I/R损伤。此外，热休克蛋白27的磷酸化状态可能会影响其降低氧化应激的能力。
Background - The small heat shock protein 27 (hsp27) increases in expression with ischemia/reperfusion (I/R) insult in the heart. One feature of the small hsps is their ability to oligomerize and form intracellular aggregates. Oligomerization pattern is governed by the phosphorylation state of the protein that may influence their ability to protect against cellular stresses.Methods and Results - We generated transgenic (tg) mice that overexpress a wild-type human hsp27 (hsp27tg) protein or a mutant hsp27 protein (mut-hsp27tg), in which serine residues (aa15, aa78, and aa82) were replaced by alanine residues, rendering them incapable of phosphorylation. Using a Langendorff perfusion model and an intraventricular balloon, we subjected hearts to 20 minutes of ischemia followed by 1 hour of reperfusion. During reperfusion, negative and positive pressure derivatives as well as developed pressures were significantly higher in both hsp27tg and mut-hsp27tg compared with control (P < 0.01) mice, with no significant difference between hsp27tg and mut-hsp27tg. Creatine kinase release during reperfusion was higher in control compared with both hsp27tg and mut-hsp27tg (P < 0.05). Malondialdehyde content as well as protein oxidation products were lower in mut-hsp27tg compared with control (P < 0.05). hsp27tg hearts possessed oligomers that ranged in size from small to large, whereas mut-hsp27tg hearts contained no small oligomers.Conclusions - These results indicate that in a tg mouse model, overexpression of either wild-type hsp27 or a nonphosphorylatable hsp27 mutant was equally capable of protecting the heart from I/R injury. Furthermore, the phosphorylation status of hsp27 may influence its ability to decrease oxidative stress.