Leucine promotes glucose uptake in skeletal muscles of rats
Leucine promotes glucose uptake in skeletal muscles of rats
复制标题
DOI：
10.1016/s0006-291x(02)02717-1
复制
发表时间：
2002-12-20
影响因子：
3.1
通讯作者：
Yagasaki, K
中科院分区：
文献类型：
--
作者：
Nishitani, S;Matsumura, T;Yagasaki, K
从正常大鼠分离比目鱼肌孵育，以评估是否亮氨酸促进葡萄糖摄取在无胰岛素的条件下，使用标记的2-脱氧葡萄糖摄取测定。2 mM亮氨酸促进葡萄糖摄取。亮氨酸的代谢物α-酮异己酸（α-KIC）也表现出类似的刺激作用，尽管其不如亮氨酸有效。用10 μ M LY 294002（一种磷脂酰肌醇3-激酶（PI 3-kinase）的特异性抑制剂）或6 μ M GF 109203 X（一种蛋白激酶C（PKC）的特异性抑制剂）预处理完全取消了亮氨酸对葡萄糖摄取的刺激。用1 μ M雷帕霉素（哺乳动物雷帕霉素靶蛋白（mTOR）的特异性抑制剂）预处理未观察到显著范围。这些结果表明，亮氨酸通过PI 3-激酶和PKC途径刺激骨骼肌中的葡萄糖转运，而不依赖于mTOR的哺乳动物靶点。他们还表明，亮氨酸刺激葡萄糖转运的胰岛素非依赖性机制。(C)2002 Elsevier Science（美国）。All rights reserved.
Soleus muscles isolated from normal rats were incubated to evaluate whether or not leucine promotes glucose uptake under insulin-free conditions, using a labeled 2-deoxyglucose uptake assay. Glucose uptake was promoted by 2 mM leucine. A metabolite of leucine, alpha-ketoisocaproic acid (alpha-KIC), also exhibited a similar stimulatory effect, although this was not as potent as leucine. Stimulation of glucose uptake by leucine was completely canceled by pre-treatment with either 10 muM LY294002, a specific inhibitor of phosphatidylinositol 3-kinase (PI3-kinase), or 6 muM GF109203X, a specific inhibitor of protein kinase C (PKC). No significant range was observed by pre-treatment with 1 muM rapamycin, a specific inhibitor of mammalian target of rapamycin (mTOR). These results suggest that leucine stimulates glucose transport in skeletal muscle via PI3-kinase and PKC pathways independently of the mammalian target of mTOR. They also suggest that leucine stimulates glucose transport by an insulin-independent mechanism. (C) 2002 Elsevier Science (USA). All rights reserved.