摘要

Objective: To investigate the effects of 5-aminolevulinic acid (ALA)-mediated photodynamic therapy (PDT) on dermal fibroblasts from hypertrophic scars (HSs). Methods: HS samples were obtained from five patients who underwent surgery, and normal skin from healthy donors was used as a control. Dermal fibroblasts were isolated and cultured with various concentrations of ALA for 6 h. Intracellular protoporphyrin IX (PpIX) was measured by confocal microscopy. After 5 h of ALA treatment, cells were irradiated by a red laser (635 nm wavelength) at a power density of 10 mW/cm(2) with an energy density from 0.5 to 4 J/cm(2). Cell survival was measured by a CCK-8 Kit after 24 h. Cell death was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling and flow cytometric analysis of annexin V. Results: Intracellular PpIX accumulation was observed in fibroblasts from HS patients and healthy donors after ALA treatment. After laser irradiation, viable cells were decreased among both cell types in a dose-dependent manner with energy density. In addition, apoptotic cell death was observed with low dose PDT, whereas necrotic cells were increased by high dose PDT. Conclusion: HS-derived fibroblasts efficiently accumulate PpIX after ALA treatment and can be eliminated via apoptosis by controlled laser irradiation.