Subcellular damage kinetics within co-cultivated WI38 and VA13-transformed WI38 human fibroblasts following 5-aminolevulinic acid-induced protoporphyrin IX formation.
The generation of the photosensitizer protoporphyrin IX (PpIX) in cells can be induced by externally applied 5-aminolevulinic acid (ALA), with that bypassing the feedback control mechanism. The aim of the present study was to investigate the onset of destructive changes in living cocultivated WI38 and VA13-transformed WI38 human fibroblasts following ALA incubation, PpIX production and subsequent irradiation by white halogen light with a dose of 2.2 kJ/m2. Specific fluorescence markers such as 3,3'-dihexyloxacarbocyanine iodide for endoplasmic reticulum (ER) staining and dihydrorhodamine for intact mitochondria mapping combined with a low light imaging system are a versatile and sensitive tool to examine the photoinduced destruction of organelles in living cells, while artifacts are minimized. Mitochondria as primary targets of PpIX undergo a condensation under irradiation and are finally destroyed. Photodynamic treatment induces further a significant decomposition of ER, although PpIX localization could not be determined. Initial destabilization and vesiculation of ER is followed by a porous network with large cisternae (indicating the breakdown of cell integrity and cell/nucleus membrane damage). Normal cocultivated lung fibroblasts showed a delay in destruction compared to the transformed WI38-VA13 cells. The observed decomposition pattern resembles the morphological pattern of apoptosis.
Uberriegler
K P
KP
Department of Physics and Biophysics, University of Salzburg, Austria.
Banieghbal
E
E
Krammer
B
B
D000622:Aminolevulinic Acid / Q000493:pharmacokinetics / Q000494:pharmacology*; D002461:Cell Line, Transformed; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism*; D006801:Humans; D008168:Lung / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000378:metabolism*; D011524:Protoporphyrins / Q000096:biosynthesis*; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism
D017319:Photosensitizing Agents; D011524:Protoporphyrins; D000622:Aminolevulinic Acid; C028025:protoporphyrin IX