Abstract |
This work relates to studies on modes of phototoxicity by protoporphyrin ( PpIX) after incubation of 5-aminolevulinic acid (5-ALA) on cultured cells. Lipid peroxidation in the 5-ALA incubated primary adenocarcinoma cells from the rectosigmoid colon (WiDr cells) was determined by measurement of protein-associated thiobarbituric acid reactive substances ( TBARS). TBARS were increased 2-fold in cells treated with 2 mM 5-ALA for 3.5 h in serum enriched medium. After illumination of 5-ALA incubated cells, TBARS were formed in a light dose dependent manner. TBARS analysis were compared with high-performance liquid chromatography (HPLC) analysis of malondialdehyde, and results indicate that 90% of the thiobarbituric reactive substances were due to malondialdehyde. Pretreating WiDr cells with alpha-tocopherol for 48 h inhibits the cytotoxic effect of 5-ALA and increases 5-fold the light dose needed to kill 50% of the cells. Pretreatment with alpha-tocopherol shows a considerable decrease (about 80%) on TBARS formation after illumination. The cellular content of alpha-tocopherol was determined by HPLC and found to be 15.3 pmol/10(6) cells.
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Authors | O A Gederaas, J W Lagerberg, O Brekke, K Berg, T M Dubbelman |
Journal | Cancer letters
(Cancer Lett)
Vol. 159
Issue 1
Pg. 23-32
(Oct 16 2000)
ISSN: 0304-3835 [Print] Ireland |
PMID | 10974402
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Photosensitizing Agents
- Thiobarbituric Acid Reactive Substances
- Vitamin E
- Malondialdehyde
- Aminolevulinic Acid
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Topics |
- Adenocarcinoma
(metabolism, pathology, prevention & control)
- Aminolevulinic Acid
(pharmacology)
- Cell Survival
(drug effects, radiation effects)
- Colonic Neoplasms
(metabolism, pathology, prevention & control)
- Dose-Response Relationship, Radiation
- Humans
- Light
- Lipid Peroxidation
(drug effects)
- Malondialdehyde
(metabolism, radiation effects)
- Photosensitizing Agents
(pharmacology)
- Thiobarbituric Acid Reactive Substances
(metabolism, radiation effects)
- Tumor Cells, Cultured
(drug effects, metabolism, radiation effects)
- Vitamin E
(pharmacokinetics, pharmacology)
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