Abstract |
The photodynamic activity of 5,10,15,20-tetrakis(4-methoxyphenyl)porphyrin ( TMP) has been investigated in two systems: reverse micelles of n-heptane/ sodium bis(2-ethylhexyl)sulfosuccinate (AOT)/water-bearing photooxidizable substrates and on a Hep-2 human carcinoma cell line. The effect of variation in the light dose and wavelength range (360-800, 455-800, and 590-800 nm) was compared in both media. The aerobic singlet oxygen-mediated photooxidation of L-tryptophan (Trp) was used as a model of biological substrate in a micellar system. A considerable increase of the observed rate constants of Trp (k(Trp)(obs)) was noted, increasing the irradiated area of the TMP spectrum. In vitro, the survival curves of Hep-2 cells, treated with TMP, were markedly dependent on the light wavelength ranges used for irradiation. A linear behavior between k(Trp)(obs) and the photoinactivation rate of Hep-2 cells was found, indicating that the singlet oxygen (1O2 ) is the main species responsible for cell inactivation. These results contributed to an understanding of the photodynamic process yielded by this porphyrin in vitro and the sensitivity of Hep-2 cells to photodamage.
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Authors | M La Penna, M G Alvarez, E I Yslas, V Rivarola, E N Durantini |
Journal | Bioorganic chemistry
(Bioorg Chem)
Vol. 29
Issue 3
Pg. 130-9
(Jun 2001)
ISSN: 0045-2068 [Print] United States |
PMID | 11437388
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Copyright | Copyright 2001 Academic Press. |
Chemical References |
- 5,10,15,20-tetrakis(4-methoxyphenyl)porphyrin
- Antineoplastic Agents
- Micelles
- Porphyrins
- Tryptophan
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Topics |
- Animals
- Antineoplastic Agents
(pharmacology)
- Cell Survival
(drug effects, radiation effects)
- Humans
- Kinetics
- Light
- Liver Neoplasms, Experimental
(drug therapy, pathology)
- Micelles
- Oxidation-Reduction
- Photochemistry
- Photochemotherapy
- Porphyrins
(therapeutic use)
- Tryptophan
(chemistry, radiation effects)
- Tumor Cells, Cultured
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