The effect of heat stress on signal transduction during the recovery from skeletal muscle atrophy induced by hindlimb-unweighted

后肢失重引起的骨骼肌萎缩恢复过程中热应激对信号转导的影响

• 批准号: 15500446
• 负责人: SUGIURA Takao
• 金额: $ 2.43万
• 依托单位: Yamaguchi University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15500446/
• 关键词: muscle atrophy; restoration; heat stress; signal transduction; 熱ショックタンパク質; カルシニューリン

It has been recently reported that Akt/mTOR/p70^<S6K>/S6 and calcineurin signaling pathways are a crucial regulator of skeletal muscle hypertrophy. We have showed that the heat stress accelerates the recovery from skeletal muscle atrophy induced by hindlimb unweighting. However, the mechanism responsible for the promoting effects of heat stress on atrophied muscles remains unclear. In this study, we investigated the role of the Akt and calcineurin signaling pathway in the recovery of the atrophied skeletal muscle with heat and its optimum exposure time. Wistar strain male rats (8-week-old) were divided into four groups : control (Con), hindlimb unweighting (HLU), heat stress for 15 (Heat 15) and 30 (Heat 30) min after hindlimb unweighting. HLU, Heat 15 and Heat 30 groups were subjected to hindlimb unweighting for 10 days. Immediately after release from unweighting, heat groups were immersed into hot water (42℃) under anesthesia. After 0, 3 and 10 days, soleus muscles were dissected. Muscle weight-to-body weight ratios of HLU and Heat 15 were significantly higher than 0 day in each group. The myofibrillar content of Heat 30 was significantly lower than Con at 10 day recovery period. The expression of phospho-mTOR in Heat 15 was significantly higher than the other groups after 0 days of muscle reloding. Phospho-S6 ribosomal levels after 3 day recovery period were significantly greater in the order : Heat 15, HLU, Heat 30 and Con. These results suggest that the heat stress promotes the recovery of atrophied skeletal muscle in part via Akt/mTOR/p70^<S6K>/S6 signaling pathway and the optimum exposure time for its promotion exist.

最近有报道称，Akt/mTOR/p70^<S6K>/S6 和钙调磷酸酶信号通路是骨骼肌肥大的关键调节因子。我们已经证明，热应激可加速后肢减重引起的骨骼肌萎缩的恢复。热应激对萎缩肌肉的促进作用的机制仍不清楚。在这项研究中，我们研究了 Akt 和钙调磷酸酶信号通路在恢复中的作用。将萎缩骨骼肌的热力及其最佳暴露时间分为四组：对照组（Con）、后肢减重组（HLU）、热应激15组（Heat 15）和后肢减重30（加热30）分钟后，加热15和加热30组进行后肢减重10天。失重后立即将热组在麻醉下浸入热水（42℃）中。0、3和10天后，解剖HLU和Heat 15的肌肉重量与体重的比率。恢复期第0天时，Heat 30的肌原纤维含量显着低于Con。Heat 15中磷酸-mTOR的表达显着。 3天恢复期后0天的磷酸-S6核糖体水平显着高于其他组：热15、HLU、热30和Con。这些结果表明热应激促进了恢复。骨骼肌萎缩部分通过 Akt/mTOR/p70^<S6K>/S6 信号通路进行，并且存在促进其促进的最佳暴露时间。

项目成果

Changes in protein kinase B (PKB/Akt) and calcineurin signaling during recovery in atrophied soleus muscle_induced by unloading.

卸载引起的萎缩比目鱼肌恢复过程中蛋白激酶 B (PKB/Akt) 和钙调磷酸酶信号的变化。

• 发表时间: 2005
• 期刊: Am J Physiol Regul Integr Comp Physiol. 288
• 作者: Sugiura T.;Abe N.;Nagano M.;et al.
• 通讯作者: et al.

Changes in protein kinase B (PKB/Akt) and calcineurin signaling during recovery in atrophied soleus muscle induced by unloading.

卸载引起的萎缩比目鱼肌恢复过程中蛋白激酶 B (PKB/Akt) 和钙调磷酸酶信号的变化。

• 发表时间: 2005
• 期刊: Am J Physiol Regul Integr Comp Physiol. 288
• 作者: Sugiura T.;Abe N.;Nagano M.;Goto K.;Sakuma K.;Naito H.;Yoshioka T.;Powers S.K.
• 通讯作者: Powers S.K.

Changes in protein kinase B(PKB/Akt) and calcineurin signaling during recovery in atrophied soleus muscle induced by unloading

卸载引起的萎缩比目鱼肌恢复过程中蛋白激酶 B (PKB/Akt) 和钙调神经磷酸酶信号的变化

• 发表时间: 2005
• 期刊: Am J Physiol Regul Integr Comp Physiol. 288
• 作者: Sugiura T.;Abe N.;Nagano M.;Goto K.;Sakuma K.;Naito H.;Yoshioka T.;Power S.K.
• 通讯作者: Power S.K.