Abstract |
The photochemistry of merocyanine 540 ( MC 540), a sensitizing dye that binds preferentially to leukemia and electrically excitable cells, has been investigated. MC 540-mediated photooxidation of histidine, arachidonate, and unsaturated phospholipid vesicles was assessed by spin label oximetry and shown to involve type II ( singlet oxygen) chemistry. The dye was also shown to be a potent sensitizer of lipid peroxidation in a natural cell membrane, the erythrocyte ghost. Inhibition by azide, stimulation by 2H2O, and identification of the cholesterol product 5 alpha-cholest-6-ene-3 beta,5-diol in this system, all were consistent with singlet oxygen intermediacy. Finally, MC 540 was found to be considerably more phototoxic to K-562 leukemia cells in 2H2O than in H2O. We conclude that singlet oxygen plays a major role in the phototherapeutic effects of this dye.
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Authors | B Kalyanaraman, J B Feix, F Sieber, J P Thomas, A W Girotti |
Journal | Proceedings of the National Academy of Sciences of the United States of America
(Proc Natl Acad Sci U S A)
Vol. 84
Issue 9
Pg. 2999-3003
(May 1987)
ISSN: 0027-8424 [Print] United States |
PMID | 3033673
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S., Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Fluorescent Dyes
- Liposomes
- Phosphatidylcholines
- Pyrimidinones
- Singlet Oxygen
- merocyanine dye
- Oxygen
- 1-palmitoyl-2-oleoylphosphatidylcholine
- Dimyristoylphosphatidylcholine
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Topics |
- Cell Line
- Cell Membrane
(drug effects, metabolism)
- Dimyristoylphosphatidylcholine
- Electron Spin Resonance Spectroscopy
- Erythrocyte Membrane
(drug effects, metabolism)
- Fluorescent Dyes
- Humans
- Leukemia, Myeloid
- Liposomes
- Oxygen
- Phosphatidylcholines
- Photochemistry
- Pyrimidinones
(pharmacology)
- Singlet Oxygen
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