Abstract
Treatment in vitro of Ehrlich ascites tumor cells or human fibroblasts with 8-methoxypsoralen (8-MOP, 2.4 microM) and UVA irradiation results in a 30% and 60% respectively reduction in lysosomal beta-galactosidase activity in situ. Under identical conditions one 8-MOP adduct was formed per 2 X 10(4) bases of DNA, one 8-MOP adduct was formed per approximately 10(4) tRNA molecules and one per approximately 100 ribosomes. It is suggested that the decrease in lysosomal beta-galactosidase activity is a result of leakage through the lysosomal membrane caused by psoralen-UVA damage of the lipids in the membrane, since no effect was found on beta-galactosidase in vitro. These results indicate that the lysosomes may also be a target for cellular photodamage by 8-methoxy-psoralen.
| Original language | English |
|---|---|
| Journal | Journal of photochemistry and photobiology. B, Biology |
| Volume | 3 |
| Issue number | 3 |
| Pages (from-to) | 437-47 |
| Number of pages | 11 |
| ISSN | 1011-1344 |
| Publication status | Published - Jun 1989 |
Keywords
- Autoradiography
- Chromatography, Thin Layer
- DNA/drug effects
- Fibroblasts/enzymology
- Humans
- Lipid Metabolism
- Lysosomes/drug effects
- Methoxsalen/pharmacology
- PUVA Therapy
- Proteins/metabolism
- RNA/drug effects
- Tumor Cells, Cultured/enzymology
- beta-Galactosidase/metabolism