Zhang Yang, Liu Songlin, Yang Xing, Yang Mingjun, Xu Wenping, Li Yaxiao, Tao Liming
Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China.
Shanghai Pesticide Research Institute, Shanghai 200032, China.
Pestic Biochem Physiol. 2016 Mar;128:37-44. doi: 10.1016/j.pestbp.2015.10.007. Epub 2015 Oct 9.
Staurosporine (STS), a wide-spectrum kinase inhibitor, is widely used in studies of apoptosis in mammalian cells. However, its physiological and mechanistic effects have never been clearly defined in insect cells, and other applications of STS have rarely been reported. The present study reveals the insecticidal activity of STS on larvae of Mythimna separata Walker, and the apoptotic mechanism induced by STS on lepidopteran Sf9 cell lines. We demonstrate that the viability of Sf9 cells is inhibited by STS in a time- and concentration-dependent manner. Intracellular biochemical assays show that STS-induced apoptosis of Sf9 cells coincides with a decrease in the mitochondrial membrane potential, the release of cytochrome c into the cytosol, a significant increase of the Bax/Bcl-2 ratio, and a marked activation of caspase-9 and caspase-3. These results indicate that a mitochondrial-dependent intrinsic pathway contributes to STS induced caspase-3 activation and apoptosis in Sf9 cells which is homologous to the mechanisms in mammalian cells. This study contributes to our understanding of the mechanism of insect cell apoptosis and suggests a possible new application of STS as a potential insecticide against Lepidopteran insect pests in agriculture.
星形孢菌素（STS）是一种广谱激酶抑制剂，广泛应用于哺乳动物细胞凋亡研究。然而，其在昆虫细胞中的生理和作用机制从未得到明确界定，且关于STS的其他应用报道也很少。本研究揭示了STS对粘虫（Mythimna separata Walker）幼虫的杀虫活性，以及STS对鳞翅目Sf9细胞系诱导的凋亡机制。我们证明，STS以时间和浓度依赖性方式抑制Sf9细胞的活力。细胞内生化分析表明，STS诱导的Sf9细胞凋亡与线粒体膜电位降低、细胞色素c释放到细胞质、Bax/Bcl-2比值显著增加以及caspase-9和caspase-3的明显激活相一致。这些结果表明，线粒体依赖性内在途径导致STS诱导Sf9细胞中caspase-3激活和凋亡，这与哺乳动物细胞中的机制同源。本研究有助于我们理解昆虫细胞凋亡机制，并提示STS作为一种潜在杀虫剂在农业中防治鳞翅目害虫可能有新的应用。
