Department of Anatomy, Tokyo Dental College, 1-2-2 Masago, Mihama-ku, Chiba City, Chiba, 261-8502, Japan.
J Muscle Res Cell Motil. 2010 Jul;31(1):71-7. doi: 10.1007/s10974-010-9209-6. Epub 2010 May 28.
This study investigated the expression of the growth factors HGF and IGF-1 during the process of muscle regeneration in mdx mice. HGF and IGF-1 are reportedly expressed during the regeneration of muscle tissue in vitro. However, few studies have focused on the role of HGF and IGF-1 during muscle regeneration in mdx mice, which lack expression of the dystrophin gene. In the present study, we examined the expression of HGF and IGF-1 in masseter muscle during muscle regeneration in mdx and B10 (control) mice using histological analysis, immunohistochemistry and Western blotting, as well as examining gene expression by RT-PCR, at 3, 4 and 9 weeks. Mdx mice showed localized HGF and IGF-1 positivity in the cytoplasm of regenerating muscle cells at 3 and 4 weeks, but hardly any reactivity was evident at 9 weeks. The control group was completely negative for IGF-1 at any of the examined time points. Western blotting showed stronger expression of HGF and IGF-1 in mdx mice than in B10 mice at 3 and 4 weeks, but at 9 weeks the expression was absent in both groups. Similar results were obtained using RT-PCR. These present results suggest that HGF and IGF-1 appear to play an important role during regeneration of the masseter muscle in mdx mice.
本研究探讨了生长因子 HGF 和 IGF-1 在 mdx 小鼠肌肉再生过程中的表达。据报道，HGF 和 IGF-1 在体外肌肉组织再生过程中表达。然而，很少有研究关注 HGF 和 IGF-1 在缺乏肌营养不良蛋白基因表达的 mdx 小鼠肌肉再生中的作用。在本研究中，我们通过组织学分析、免疫组织化学和 Western blot 检测以及 RT-PCR 检测，研究了 mdx 和 B10（对照）小鼠肌肉再生过程中 HGF 和 IGF-1 在咀嚼肌中的表达，分别在 3、4 和 9 周进行检测。mdx 小鼠在 3 周和 4 周时，再生肌肉细胞的细胞质中出现局部 HGF 和 IGF-1 阳性，但在 9 周时几乎没有反应。对照组在任何检测时间点均未检测到 IGF-1。Western blot 显示 mdx 小鼠在 3 周和 4 周时 HGF 和 IGF-1 的表达强于 B10 小鼠，但在 9 周时两组均无表达。RT-PCR 也得到了相似的结果。这些结果表明，HGF 和 IGF-1 在 mdx 小鼠咀嚼肌再生过程中似乎发挥了重要作用。
