Journal of Bioenergetics and Biomembranes

, Volume 39, Issue 1, pp 85–89

Mitochondria are targets of photodynamic therapy

Mini Review

DOI: 10.1007/s10863-006-9064-8

Cite this article as:
Hilf, R. J Bioenerg Biomembr (2007) 39: 85. doi:10.1007/s10863-006-9064-8


Photodynamic Therapy (PDT) is an evolving cancer treatment that depends on three known and variable components: photosensitizer, light and oxygen. Optimization of these variables yields reactive oxygen species, mainly singlet oxygen, that damage cellular components leading to cytotoxicity. Our research has demonstrated that porphyrin sensitizers, in particular, significantly inhibit the inner mitochondrial membrane enzymes cytochrome c oxidase and F0F1 ATP synthase. These results were obtained from an in vivo-in vitro experimental protocol that exposes sensitizers to metabolic and pharmacokinetic events. The resulting inhibition of oxidative phosphorylation was expected to reduce ATP levels, which were quantitated in cells and were confirmed by 31P-NMR spectroscopy of tumors in situ in animals treated with PDT.

Based on these findings, and more recent investigations of apoptosis, there is little doubt that mitochondria are critical targets in the actions of PDT.


Photodynamic therapyMitochondrial targetsEnzyme inhibitionATP levelsTumor cytotoxicity

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  1. 1.Department of Biochemistry and Biophysics, School of Medicine and DentistryUniversity of RochesterRochesterUSA