Graduate School of Semiconductor and Chemical Engineering, Chonbuk National University, 664-14 Deokjin-dong, 1Ga Deokjin-Gu, Jeonju 561-756, South Korea.
Appl Biochem Biotechnol. 2011 Apr;163(8):1002-11. doi: 10.1007/s12010-010-9104-z. Epub 2010 Oct 16.
Exposure of mammalian cells to oxidative stress alters lysosomal enzymes. Through cytochemical analysis of lysosomes with LysoTracker, we demonstrated that the number and fluorescent intensity of lysosome-like organelles in HeLa cells increased with exposure to hydrogen peroxide (H₂O₂), 6-hydroxydopamine (6-OHDA), and UVB irradiation. The lysosomes isolated from HeLa cells exposed to three oxidative stressors showed the enhanced antimicrobial activity against Escherichia coli. Further, when lysosomes that were isolated from HeLa cells exposed by oxidative stress were treated to normal HeLa cells, the viability of the HeLa cells was drastically reduced, suggesting increased in vitro lysosomal function (i.e., antimicrobial activity, apoptotic cell death). In addition, we also found that cathepsin B and D were implicated in increased in vitro lysosomal function when isolated from HeLa cells exposed by oxidative stress. Decrease in cathepsin B activity and increase in cathepsin D activity were observed in lysosomes isolated from HeLa cells after treatment with H₂O₂, 6-ODHA, or UVB, but cathepsin B and D were not the sole factors to induce cell death by in vitro lysosomal function. Therefore, these studies suggest a new approach to use lysosomes as antimicrobial agents and as new materials for treating cancer cell lines.
哺乳动物细胞暴露在氧化应激下会改变溶酶体酶。通过使用 LysoTracker 对溶酶体进行细胞化学分析，我们证明了在 HeLa 细胞中，随着过氧化氢 (H₂O₂)、6-羟基多巴胺 (6-OHDA) 和 UVB 照射的暴露，溶酶体样细胞器的数量和荧光强度增加。从暴露于三种氧化应激源的 HeLa 细胞中分离出的溶酶体对大肠杆菌表现出增强的抗菌活性。此外，当将从氧化应激下暴露的 HeLa 细胞中分离出的溶酶体处理正常的 HeLa 细胞时，HeLa 细胞的活力明显降低，表明体外溶酶体功能增加（即抗菌活性、凋亡细胞死亡）。此外，我们还发现，当从氧化应激下暴露的 HeLa 细胞中分离出组织蛋白酶 B 和 D 时，体外溶酶体功能增加。在用 H₂O₂、6-ODHA 或 UVB 处理后，从 HeLa 细胞中分离出的溶酶体中观察到组织蛋白酶 B 活性降低和组织蛋白酶 D 活性增加，但组织蛋白酶 B 和 D 并非唯一诱导体外溶酶体功能导致细胞死亡的因素。因此，这些研究为将溶酶体用作抗菌剂和治疗癌细胞系的新材料提供了一种新方法。
