Dept. of Pharmacology, School of Basic Medical Sciences, Kunming Medical College, Kunming 650500, China.
Eur J Pharmacol. 2010 Oct 25;645(1-3):23-31. doi: 10.1016/j.ejphar.2010.07.011. Epub 2010 Jul 23.
Promoting human embryonic stem cell (hESC)-derived-neural progenitor survival in the pro-apoptotic niche is pivotal for stem cell replacement therapy. The present study was designed to investigate the protective effect of hepatocyte growth factor (HGF) on hESC-derived neural progenitor injured by hydrogen peroxide (H(2)O(2)) exposure. Treatment of hESC-derived neural progenitor cells with HGF prior to H(2)O(2) exposure conferred protective effect against oxidative stress-induced apoptosis. HGF treatment increased both phosphoinositide 3-kinase (PI3K)/Akt and extracellular signal-regulated kinase1/2 (ERK1/2) phosphorylation. However, selective inhibition of each pathway supported that the activation of PI3K/AKT, but not ERK1/2, provides survival advantage to the neural progenitor cells. Further investigation indicated that HGF pretreatment could attenuate the decrease of the expression of Bcl-2 protein induced by H(2)O(2), whereas the level of Bax was not affected. Additionally, we observed that H(2)O(2)-induced decrease of mitochondrial transmembrane potential, release of cytochrome c and increase of caspase-3 activation were alleviated by HGF pretreatment. These effects of HGF could be reversed by inhibition of the PI3K/Akt and ERKs pathways, indicating PI3K/Akt and ERKs signaling might be involved in HGF-mediated regulation of mitochondrial apoptotic pathway mediated by H(2)O(2). The neuroprotective effect of HGF might potentially be useful in stem cell-based therapies for neurodegenerative disorders.
促进人胚胎干细胞(hESC)衍生的神经祖细胞在促凋亡龛中的存活对于干细胞替代治疗至关重要。本研究旨在探讨肝细胞生长因子(HGF)对过氧化氢(H2O2)暴露损伤的 hESC 衍生神经祖细胞的保护作用。在 H2O2 暴露前用 HGF 处理 hESC 衍生的神经祖细胞可对氧化应激诱导的细胞凋亡产生保护作用。HGF 处理增加了磷酸肌醇 3-激酶(PI3K)/Akt 和细胞外信号调节激酶 1/2(ERK1/2)的磷酸化。然而,选择性抑制每条途径表明,PI3K/AKT 的激活而不是 ERK1/2 的激活为神经祖细胞提供了生存优势。进一步的研究表明,HGF 预处理可以减轻 H2O2 诱导的 Bcl-2 蛋白表达减少,而 Bax 水平不受影响。此外,我们观察到 HGF 预处理可以减轻 H2O2 诱导的线粒体跨膜电位下降、细胞色素 c 释放和 caspase-3 激活增加。HGF 的这些作用可以通过抑制 PI3K/Akt 和 ERKs 途径来逆转,表明 PI3K/Akt 和 ERKs 信号可能参与了 HGF 介导的 H2O2 诱导的线粒体凋亡途径的调节。HGF 的神经保护作用可能在基于干细胞的神经退行性疾病治疗中具有潜在的应用价值。