PDT with ALA/PPIX enhanced by prolonged light exposure putatively by targeting mitochondria

Steven Jacques, Sergio K. Furuzawa, Tom Rodriguez

Research output: Chapter in Book/Report/Conference proceedingConference contribution

5 Citations (Scopus)

Abstract

The synthesis of protoporphyrin IX (PPIX), a photosensitizer, occurs in the mitochondria of cells. Continuous light exposure activates the PPIX while it still resides in the mitochondria. The mitochondria are especially sensitive sites for lethal damage. In tissue culture experiments, cells were treated by PDT in two ways: (1) the cells were preloaded with PPIX by overnight incubation in medium containing ALA then exposed to light for various time periods, and (2) cells were not preloaded but rather were placed in medium containing ALA at the start of light exposure. Light exposure was 100 mW/cm2. After exposure the cells were plated and incubated for seven days to watch for colony formation. The results of experiment 1 showed that in preloaded cells, the large amount of PPIX that accumulates was easily photobleached in just 5 minutes which yielded a drop in cell survival to a level of 2 percent. Further light exposure up to an hour had no additional effect on cell survival. But when light exposure was continued past one hour, cell survival began to drop again. The results of experiment 2 showed that light exposure had no effect in the first hour, but thereafter continued exposure caused continued exponential drop in cell survival. In both experiments, cell survival dropped to 1/e its value for every 8 minutes of continued light exposure.

Original languageEnglish (US)
Title of host publicationProceedings of SPIE - The International Society for Optical Engineering
Pages74-78
Number of pages5
Volume2972
DOIs
StatePublished - 1997
EventOptical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy VI - San Jose, CA, United States
Duration: Feb 8 1997Feb 8 1997

Other

OtherOptical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy VI
CountryUnited States
CitySan Jose, CA
Period2/8/972/8/97

Fingerprint

Mitochondria
mitochondria
Cell
Cells
cells
Experiments
Experiment
Tissue culture
Photosensitizing Agents
Photosensitizers
1-phenyl-3,3-dimethyltriazene
protoporphyrin IX
Photosensitizer
Tissue Culture
clocks
Accumulate
Percent
damage
Damage
Synthesis

ASJC Scopus subject areas

  • Applied Mathematics
  • Computer Science Applications
  • Electrical and Electronic Engineering
  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

Jacques, S., Furuzawa, S. K., & Rodriguez, T. (1997). PDT with ALA/PPIX enhanced by prolonged light exposure putatively by targeting mitochondria. In Proceedings of SPIE - The International Society for Optical Engineering (Vol. 2972, pp. 74-78) https://doi.org/10.1117/12.273489

PDT with ALA/PPIX enhanced by prolonged light exposure putatively by targeting mitochondria. / Jacques, Steven; Furuzawa, Sergio K.; Rodriguez, Tom.

Proceedings of SPIE - The International Society for Optical Engineering. Vol. 2972 1997. p. 74-78.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Jacques, S, Furuzawa, SK & Rodriguez, T 1997, PDT with ALA/PPIX enhanced by prolonged light exposure putatively by targeting mitochondria. in Proceedings of SPIE - The International Society for Optical Engineering. vol. 2972, pp. 74-78, Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy VI, San Jose, CA, United States, 2/8/97. https://doi.org/10.1117/12.273489
Jacques S, Furuzawa SK, Rodriguez T. PDT with ALA/PPIX enhanced by prolonged light exposure putatively by targeting mitochondria. In Proceedings of SPIE - The International Society for Optical Engineering. Vol. 2972. 1997. p. 74-78 https://doi.org/10.1117/12.273489
Jacques, Steven ; Furuzawa, Sergio K. ; Rodriguez, Tom. / PDT with ALA/PPIX enhanced by prolonged light exposure putatively by targeting mitochondria. Proceedings of SPIE - The International Society for Optical Engineering. Vol. 2972 1997. pp. 74-78
@inproceedings{f7580d27cc9e4e16a7df3fa198d304fd,
title = "PDT with ALA/PPIX enhanced by prolonged light exposure putatively by targeting mitochondria",
abstract = "The synthesis of protoporphyrin IX (PPIX), a photosensitizer, occurs in the mitochondria of cells. Continuous light exposure activates the PPIX while it still resides in the mitochondria. The mitochondria are especially sensitive sites for lethal damage. In tissue culture experiments, cells were treated by PDT in two ways: (1) the cells were preloaded with PPIX by overnight incubation in medium containing ALA then exposed to light for various time periods, and (2) cells were not preloaded but rather were placed in medium containing ALA at the start of light exposure. Light exposure was 100 mW/cm2. After exposure the cells were plated and incubated for seven days to watch for colony formation. The results of experiment 1 showed that in preloaded cells, the large amount of PPIX that accumulates was easily photobleached in just 5 minutes which yielded a drop in cell survival to a level of 2 percent. Further light exposure up to an hour had no additional effect on cell survival. But when light exposure was continued past one hour, cell survival began to drop again. The results of experiment 2 showed that light exposure had no effect in the first hour, but thereafter continued exposure caused continued exponential drop in cell survival. In both experiments, cell survival dropped to 1/e its value for every 8 minutes of continued light exposure.",
author = "Steven Jacques and Furuzawa, {Sergio K.} and Tom Rodriguez",
year = "1997",
doi = "10.1117/12.273489",
language = "English (US)",
volume = "2972",
pages = "74--78",
booktitle = "Proceedings of SPIE - The International Society for Optical Engineering",

}

TY - GEN

T1 - PDT with ALA/PPIX enhanced by prolonged light exposure putatively by targeting mitochondria

AU - Jacques, Steven

AU - Furuzawa, Sergio K.

AU - Rodriguez, Tom

PY - 1997

Y1 - 1997

N2 - The synthesis of protoporphyrin IX (PPIX), a photosensitizer, occurs in the mitochondria of cells. Continuous light exposure activates the PPIX while it still resides in the mitochondria. The mitochondria are especially sensitive sites for lethal damage. In tissue culture experiments, cells were treated by PDT in two ways: (1) the cells were preloaded with PPIX by overnight incubation in medium containing ALA then exposed to light for various time periods, and (2) cells were not preloaded but rather were placed in medium containing ALA at the start of light exposure. Light exposure was 100 mW/cm2. After exposure the cells were plated and incubated for seven days to watch for colony formation. The results of experiment 1 showed that in preloaded cells, the large amount of PPIX that accumulates was easily photobleached in just 5 minutes which yielded a drop in cell survival to a level of 2 percent. Further light exposure up to an hour had no additional effect on cell survival. But when light exposure was continued past one hour, cell survival began to drop again. The results of experiment 2 showed that light exposure had no effect in the first hour, but thereafter continued exposure caused continued exponential drop in cell survival. In both experiments, cell survival dropped to 1/e its value for every 8 minutes of continued light exposure.

AB - The synthesis of protoporphyrin IX (PPIX), a photosensitizer, occurs in the mitochondria of cells. Continuous light exposure activates the PPIX while it still resides in the mitochondria. The mitochondria are especially sensitive sites for lethal damage. In tissue culture experiments, cells were treated by PDT in two ways: (1) the cells were preloaded with PPIX by overnight incubation in medium containing ALA then exposed to light for various time periods, and (2) cells were not preloaded but rather were placed in medium containing ALA at the start of light exposure. Light exposure was 100 mW/cm2. After exposure the cells were plated and incubated for seven days to watch for colony formation. The results of experiment 1 showed that in preloaded cells, the large amount of PPIX that accumulates was easily photobleached in just 5 minutes which yielded a drop in cell survival to a level of 2 percent. Further light exposure up to an hour had no additional effect on cell survival. But when light exposure was continued past one hour, cell survival began to drop again. The results of experiment 2 showed that light exposure had no effect in the first hour, but thereafter continued exposure caused continued exponential drop in cell survival. In both experiments, cell survival dropped to 1/e its value for every 8 minutes of continued light exposure.

UR - http://www.scopus.com/inward/record.url?scp=58049176734&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=58049176734&partnerID=8YFLogxK

U2 - 10.1117/12.273489

DO - 10.1117/12.273489

M3 - Conference contribution

VL - 2972

SP - 74

EP - 78

BT - Proceedings of SPIE - The International Society for Optical Engineering

ER -