Administration of insulin to newly hatched chicks improves growth performance via impairment of MyoD gene expression and enhancement of cell proliferation in chicken myoblasts
Administration of insulin to newly hatched chicks improves growth performance via impairment of MyoD gene expression and enhancement of cell proliferation in chicken myoblasts
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DOI：
10.1016/j.ygcen.2011.11.043
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发表时间：
2012-02-01
影响因子：
2.7
通讯作者：
Kamada, Tosihiko
中科院分区：
文献类型：
--
作者：
Sato, Kan;Aoki, Michiru;Kamada, Tosihiko
胰岛素/PI3K/Akt 信号通路与 C2C12 细胞的分化密切相关，向培养基中添加 IGF 和胰岛素已证明这一点。在这项研究中，我们在体外和体内表征了胰岛素在鸡成肌细胞增殖和分化中的作用，并揭示了这种外源激素如何在分化过程中影响生肌基因的新细节。与单独在分化培养基中培养的细胞相比，在补充胰岛素的分化培养基（含有 2% FBS 的 DMEM）中培养的鸡成肌细胞在培养 12 小时后表现出 MyoD 和肌细胞生成素 mRNA 表达显着降低。与对照培养物相比，在补充有胰岛素的分化培养基中培养的细胞中的 MyoD 和肌生成素免疫反应蛋白相当低。在含有胰岛素的分化培养基中添加 LY294002（一种 PI3K 抑制剂）可诱导成肌细胞分化。孵育12小时后，在这些细胞中观察到MyoD和肌细胞生成素mRNA表达显着增加，并且表达水平与单独用分化培养基孵育的对照细胞相似。通过向分化培养基中添加胰岛素来增加 DNA 含量和磷酸化 Erk1/2 蛋白水平。这些结果表明胰岛素及其信号通路在鸡成肌细胞分化中发挥抑制作用。在 1 日龄注射胰岛素或甲苯磺丁脲的 3 日龄雏鸡的骨骼肌中观察到高水平的 Pax7 mRNA。此外，在 1 日龄时施用胰岛素或甲苯磺丁脲的鸡在 21 日龄和 50 日龄时的体重显着高于对照鸡。这些结果不仅详细说明了成肌细胞胰岛素作用的物种特异性差异，而且还提供了可用于提高鸡肉产量的新信息。 (C) 2011 Elsevier Inc. 保留所有权利。
The insulin/PI3K/Akt signaling pathway is strongly involved in the differentiation of C2C12 cells, as has been demonstrated by the addition of IGFs and insulin to culture media. In this study, we have characterized the role of insulin in chick myoblast proliferation and differentiation in vitro and in vivo, and have revealed novel details of how this exogenous hormone influences myogenic genes during differentiation. Chick myoblast cells cultured in differentiation medium (DMEM containing 2% FBS) supplemented with insulin exhibited a significant decrease in MyoD and myogenin mRNA expression after 12 h of culture compared to cells cultured in differentiation media alone. MyoD and myogenin immunoreactive proteins in cells cultured in differentiation medium supplemented with insulin were quite low compared to those in control culture. Supplementation of the differentiation media containing insulin with LY294002 (a PI3K inhibitor) induced myoblast differentiation. A significant increase in MyoD and myogenin mRNA expression was observed in these cells after incubation for 12 h, and the level of expression was similar to that of control cells incubated with differentiation media alone. The DNA content and the phosphor-Erk1/2 protein level were increased by the addition of insulin to the differentiation medium. These results suggest that insulin and its signaling pathway play an inhibitory role in chick myoblast differentiation. A high level of Pax7 mRNA was observed in the skeletal muscle of 3-day-old chicks administered insulin or tolbutamide at 1-day-of-age. In addition, body weight at 21 and 50 days-of-age was significantly greater for chickens administered insulin or tolbutamide at 1-day-of-age than for control chickens. These results detail not only species-specific differences in insulin action for myoblasts but also provide novel information that may be used for the improvement of chicken meat production. (C) 2011 Elsevier Inc. All rights reserved.