Altered regulation of contraction-induced Akt/mTOR/p70S6k pathway signaling in skeletal muscle of the obese Zucker rat.
Altered regulation of contraction-induced Akt/mTOR/p70S6k pathway signaling in skeletal muscle of the obese Zucker rat.
复制标题
改变肥胖 Zucker 大鼠骨骼肌中收缩诱导的 Akt/mTOR/p70S6k 通路信号传导的调节。
DOI：
10.1155/2009/384683
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发表时间：
2009
影响因子：
--
通讯作者：
Blough,EricR
中科院分区：
文献类型：
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作者：
Katta,Anjaiah;Kakarla,Sunil;Wu,Miaozong;Paturi,Satyanarayana;Gadde,MuraliK;Arvapalli,Ravikumar;Kolli,Madhukar;Rice,KevinM;Blough,EricR
肌肉负荷增加导致70 kDa核糖体S6激酶（p70 S6 k）磷酸化，并且该事件与抗阻运动后肌肉适应的程度密切相关。胰岛素抵抗或与这种疾病相关的合并症是否会影响骨骼肌在运动刺激后激活p70 S6 k信号传导的能力仍不清楚。在这里，我们比较了在单次增加收缩负荷后，瘦和胰岛素抵抗性肥胖Zucker大鼠的跖肌中收缩诱导的p70 S6 k信号转导激活。与瘦型动物相比，肥胖动物中p70 S6 k（Thr 389; 37.2%和Thr 421/Ser 424; 101.4%）、Akt（Thr 308; 25.1%）和mTOR（Ser 2448; 63.0%）的基础磷酸化水平更高。在两种模型中，收缩增加了p70 S6 k（Thr 389）、Akt（Ser 473）和mTOR（Ser 2448）的磷酸化，但模型之间激活的幅度和动力学不同。这些结果表明，收缩诱导的p70 S6 k信号转导激活在胰岛素抵抗性肥胖Zucker大鼠的肌肉中改变。
Increased muscle loading results in the phosphorylation of the 70 kDa ribosomal S6 kinase (p70S6k), and this event is strongly correlated with the degree of muscle adaptation following resistance exercise. Whether insulin resistance or the comorbidities associated with this disorder may affect the ability of skeletal muscle to activate p70S6k signaling following an exercise stimulus remains unclear. Here, we compare the contraction‐induced activation of p70S6k signaling in the plantaris muscles of lean and insulin resistant obese Zucker rats following a single bout of increased contractile loading. Compared to lean animals, the basal phosphorylation of p70S6k (Thr389; 37.2% and Thr421/Ser424; 101.4%), Akt (Thr308; 25.1%), and mTOR (Ser2448; 63.0%) was higher in obese animals. Contraction increased the phosphorylation of p70S6k (Thr389), Akt (Ser473), and mTOR (Ser2448) in both models however the magnitude and kinetics of activation differed between models. These results suggest that contraction‐induced activation of p70S6k signaling is altered in the muscle of the insulin resistant obese Zucker rat.