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A Photodynamic Approach to Study Function of Intracellular Vesicle Rupture
Published on: March 17, 2023
Graphene quantum dots as autophagy-inducing photodynamic agents
Zoran M Markovic1, Biljana Z Ristic, Katarina M Arsikin
1Vinca Institute of Nuclear Sciences, University of Belgrade, 11000 Belgrade, Serbia. zormark@vinca.rs
Biomaterials
|July 17, 2012
Summary
Photoexcited graphene quantum dots (GQD) generate reactive oxygen species, inducing cell death in glioma cells via oxidative stress. GQD show potential for photodynamic therapy but require further toxicity assessment.
Area of Science:
- Biomedical Engineering
- Materials Science
- Cell Biology
Background:
- Graphene quantum dots (GQD) possess excellent photoluminescent properties, making them promising for biomedical applications.
- However, the cytotoxicity of GQD, particularly under irradiation, remains incompletely understood.
Purpose of the Study:
- To investigate the photodynamic effects and cytotoxicity of electrochemically produced GQD on human glioma cells.
- To elucidate the mechanisms of cell death induced by photoexcited GQD.
Main Methods:
- Electrochemical production of GQD.
- Irradiation of U251 human glioma cells with blue light (470 nm) in the presence of GQD.
- Assessment of reactive oxygen species (ROS) generation, including singlet oxygen.
- Analysis of cell death pathways, including apoptosis and autophagy markers (e.g., phosphatidylserine externalization, caspase activation, DNA fragmentation, LC3B conversion).
- Genetic inactivation of the autophagy-essential LC3B protein.
Main Results:
- Photoexcited GQD generated ROS, leading to oxidative stress and U251 cell death.
- Cell death exhibited characteristics of both apoptosis and autophagy.
- Genetic inactivation of LC3B partially reduced the photodynamic cytotoxicity of GQD.
- These findings highlight the dual nature of GQD in inducing cell death.
Conclusions:
- GQD demonstrate potential as agents in photodynamic therapy due to their ability to induce cancer cell death.
- The observed cytotoxicity warrants careful consideration for safe biomedical applications.
- Further research is needed to fully characterize GQD toxicity and optimize their therapeutic potential.
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