Department of Anatomy, Korea University College of Medicine, Anamdong 5 ga, Seungbuk gu, Seoul, Republic of Korea.
Life Sci. 2010 Jul 3;87(1-2):42-8. doi: 10.1016/j.lfs.2010.05.017. Epub 2010 May 31.
Clozapine has previously been implicated in the dysregulation of energy balance and glucose metabolism in the central nervous system, but its effects in the periphery have yet to be thoroughly elucidated. The objective of this study was to characterize the effects of clozapine on AMP-activated protein kinase (AMPK) activity in the skeletal muscles.
Myotube C2C12 cells were incubated under control conditions, or with clozapine. Expression levels of phosphorylation status of AMPK and its direct downstream Acetyl-CoA carboxylase (ACC) were analyzed by Western blot. Intracellular calcium concentration was measured with calcium indicator dye, fluo-3AM. 2-deoxyglucose uptake was assessed via the scintillation count.
We reported that clozapine activated AMPK in mouse C2C12 myotubes and also stimulated glucose uptake. Clozapine also increased intracellular calcium concentrations of C2C12 cells, and pretreatment with either ethylenediaminetetraacetic acid (EDTA), an extracellular calcium chelator, or 1.8-naphthoylene benzimidazole-3-carboxylic acid (STO-609), a Ca(2+)/calmodulin-dependent protein kinase kinase (CaMKK) inhibitor, blocked clozapine-induced AMPK activation.
These results demonstrate that clozapine increases glucose uptake through CaMKK-AMPK pathway in myotube C2C12 cells.
氯氮平先前已被牵涉到中枢神经系统能量平衡和葡萄糖代谢的失调中，但它在周围组织中的作用尚未被彻底阐明。本研究的目的是描述氯氮平对骨骼肌中 AMP 激活蛋白激酶（AMPK）活性的影响。
在对照条件下或用氯氮平孵育 C2C12 成肌细胞。通过 Western blot 分析 AMPK 的磷酸化状态及其直接下游的乙酰辅酶 A 羧化酶（ACC）的表达水平。用钙指示剂染料 fluo-3AM 测量细胞内钙离子浓度。通过闪烁计数评估 2-脱氧葡萄糖摄取。
我们报道氯氮平在小鼠 C2C12 成肌细胞中激活了 AMPK，并刺激了葡萄糖摄取。氯氮平还增加了 C2C12 细胞的细胞内钙离子浓度，而用 EDTA（一种细胞外钙离子螯合剂）或 1.8-萘酰亚胺苯并咪唑-3-羧酸（STO-609，一种 Ca（2+）/钙调蛋白依赖性蛋白激酶激酶（CaMKK）抑制剂）预处理可阻断氯氮平诱导的 AMPK 激活。
这些结果表明，氯氮平通过 CaMKK-AMPK 途径增加 C2C12 成肌细胞中的葡萄糖摄取。
