Shang Ke, Zhang Junfeng, Amna Touseef, Yang Jieun, Cheng Xiangchao, Zhang Chunjie, Hwang Inho
Department of Animal Science and Biotechnology, Chonbuk National University, Chonju, 561-756, Republic of Korea.
Mol Biol Rep. 2015 Aug;42(8):1281-8. doi: 10.1007/s11033-015-3869-7. Epub 2015 Mar 27.
This investigation was under taken to explore probable mechanisms and signal pathways involved in cytotoxicity induced by bacterial endotoxin lipopolysaccharide (LPS). Herein, we selected muscle precursor C2C12 myoblasts as representative cells to test effect of calpain inhibitor 3-(4-iodophenyl)-2-mercapto-(Z)-2-propenoic acid (PD150606) on LPS induced inflammation and apoptosis. In order to rule out the toxicity of endotoxin, mouse myoblasts were exposed to various concentrations of LPS and viability of cells and morphology were assessed using CCK-8 assay and simple microscopy respectively. Apoptotic cell death was examined by fluorescence microscope at regular time intervals. Additionally, LPS induced apoptosis in C2C12 cells were determined by mRNA expression of µ-calpain, caspase-3 and tumor necrosis factor alpha (TNF-α) and were quantified by qRT-PCR. Our results point out that LPS stimulation produced dose dependent toxicity in muscle precursor cells. Pre-treatment with a calpain inhibitor can significantly attenuate LPS-induced inflammation/apoptosis. Results of present research determined that mRNA expression of aforesaid genes was amplified (p<0.05) in LPS stimulated C2C12 cells, whereas a noticeable drop off in mRNA expression of these genes was observed when pre-exposed with calpain inhibitor PD150606. Our study has outlined the current understanding regarding the connection between µ-calpain and caspase-3 in skeletal muscle wasting and as a result provides suitable choice for designing promising chemotherapeutic system for muscle illness and atrophy.
本研究旨在探索细菌内毒素脂多糖(LPS)诱导细胞毒性所涉及的可能机制和信号通路。在此,我们选择肌肉前体细胞C2C12成肌细胞作为代表性细胞,以测试钙蛋白酶抑制剂3-(4-碘苯基)-2-巯基-(Z)-2-丙烯酸(PD150606)对LPS诱导的炎症和凋亡的影响。为了排除内毒素的毒性,将小鼠成肌细胞暴露于不同浓度的LPS中,并分别使用CCK-8法和普通显微镜评估细胞活力和形态。定期通过荧光显微镜检查凋亡细胞死亡情况。此外,通过µ-钙蛋白酶、半胱天冬酶-3和肿瘤坏死因子α(TNF-α)的mRNA表达来确定LPS诱导的C2C12细胞凋亡,并通过qRT-PCR进行定量。我们的结果表明,LPS刺激在肌肉前体细胞中产生剂量依赖性毒性。用钙蛋白酶抑制剂预处理可显著减轻LPS诱导的炎症/凋亡。本研究结果确定,在LPS刺激的C2C12细胞中,上述基因的mRNA表达增加(p<0.05),而当预先用钙蛋白酶抑制剂PD150606处理时,观察到这些基因的mRNA表达明显下降。我们的研究概述了目前对骨骼肌萎缩中µ-钙蛋白酶和半胱天冬酶-3之间联系的理解,因此为设计有前景的肌肉疾病和萎缩化疗系统提供了合适的选择。