Increased in vitro lysosomal function in oxidative stress-induced cell lines.
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.
Yoon
Jihee
J
Graduate School of Semiconductor and Chemical Engineering, Chonbuk National University, 664-14 Deokjin-dong, 1Ga Deokjin-Gu, Jeonju 561-756, South Korea.
Bang
Seung Hyuck
SH
Park
Jin-Soo
JS
Chang
Suk-Tai
ST
Kim
Yang-Hoon
YH
Min
Jiho
J
D017209:Apoptosis; D002401:Cathepsin B / Q000378:metabolism; D002402:Cathepsin D / Q000378:metabolism; D006367:HeLa Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008247:Lysosomes / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D018384:Oxidative Stress / Q000187:drug effects / Q000528:radiation effects; D014466:Ultraviolet Rays
D006861:Hydrogen Peroxide; D002401:Cathepsin B; D002402:Cathepsin D