Glutamine protects articular chondrocytes from heat stress and NO-induced apoptosis with HSP70 expression
Glutamine protects articular chondrocytes from heat stress and NO-induced apoptosis with HSP70 expression
复制标题
DOI：
10.1016/j.joca.2005.12.008
复制
发表时间：
2006-06-01
影响因子：
7
通讯作者：
Kubo, T.
中科院分区：
文献类型：
--
作者：
Tonomura, H.;Takahashi, K. A.;Kubo, T.
目的：目的：探讨L-谷氨酰胺（Gln）对热应激和一氧化氮（NO）诱导的软骨细胞应激反应的影响。在一些实验中，还用槲皮素（Que）（一种热休克蛋白70（HSP 70）抑制剂）处理细胞。热应激（43摄氏度）施加到细胞0-120分钟。细胞凋亡诱导的0.5 mM硝普钠（SNP）二水合物，产生NO。应激负荷后，HSP 70的表达通过Western印迹分析检测。乳酸脱氢酶（LDH）释放和四氮唑盐为基础的测定，而凋亡进行了评估Hoechst 33342染色，TUNEL法和活性caspase-3 determination.Results：Gin表现出剂量依赖性增强作用的应激介导的诱导HSP 70，而在没有任何应力单独Gin诱导HSP 70。在加热或SNP加载后，软骨细胞表现出活力的严重降低，而细胞毒性结果几乎完全被Gin调节所消除。Gin的保护作用可被Que所阻断，Que能有效抑制应激诱导的软骨细胞HSP 70表达。Gin还使软骨细胞对SNP处理的culture.Conclusion中常见的NO诱导的凋亡不敏感：本研究表明，Gin处理软骨细胞可保护细胞免受热应激和NO诱导的凋亡。Gin的这些软骨保护作用可能是由HSP 70介导的。(c)2005年国际骨关节炎研究学会。由爱思唯尔有限公司出版。保留所有权利。
Objective: To investigate the effect of L-glutamine (Gin) on stress responses of chondrocytes exposed to heat stress or nitric oxide (NO).Methods: Cultures of articular chondrocytes were established from rabbit joints, and treated for 12 h with various concentrations of Gin (0-20 mM). In some experiments, cells were also treated with quercetin (Que), a heat shock protein 70 (HSP70) inhibitor. Heat stress (43 degrees C) was applied to the cells for 0-120 min. Apoptosis was induced by 0.5 mM sodium nitroprusside (SNP) dihydrate that produces NO. After stress loading, HSP70 expression was detected by Western blot analysis. Cell viability was assessed by lactate dehydrogenase (LDH) release and tetrazolium salt-based assays, while apoptosis was evaluated by Hoechst 33342 staining, TUNEL methods and active caspase-3 determination.Results: Gin demonstrated dose-dependent enhancing effect on stress-mediated induction of HSP70, while in the absence of any stress HSP70 was not induced by Gin alone. After heating or SNP loading, chondrocytes showed severe reduction in viability, while the cytotoxic outcome was almost completely abrogated by conditioning with Gin. The protective effect of Gin was significantly blocked by Que that effectively suppressed stress-induced HSP70 expression in chondrocytes. The Gin also rendered chondrocytes unsusceptible to NO-induced apoptosis that was frequently seen in SNP-treated culture.Conclusion: This study demonstrated that the treatment of chondrocytes with Gin protected the cells from heat stress and NO-induced apoptosis. These chondroprotective effects of Gin may be mediated by HSP70. (c) 2005 OsteoArthritis Research Society International. Published by Elsevier Ltd. All rights reserved.