Photodynamic studies of cationic porphyrin 5-(4-trimethylammoniumphenyl)-10,15,20-tris(2,4,6-trimethoxyphenyl)porphyrin: biological consequences in a human carcinoma cell line.

M. G. ALVAREZ, F. PRINCIPE, M. E. MILANESIO, E. N. DURANTINI, V. RIVAROLA

Córdoba

Congreso; Asociación de Bilogía de Córdoba; 2004

Photodynamic therapy (PDT) is a promising treatment for a photosensitizing of solid malignancies involving the administration of a photosensitizing compound and the accumulation of the sensitizer in the target cells, followed by selective irradiation of the lesion with visible light. Intervention of the excited photosensitizer with molecular oxygen results in the formation of singlet oxygen, which are believed to be responsible for cell destruction. The aim of the present study is to evaluate the photodynamic effects of 5-(4-trimethylammonium phenyl) - 10, 15, 20 - tris (2, 4, 6 – trimethoxyphenyl) porphyrin (CP) on Hep-2 cells. The uptake is not an energy dependent process until evaluated concentration (10 mM). CP does not affect the cell viability in the absences of light (0.1; 1 and 10 mM). In contrast, the combination of CP with visible light induces a decrease in cell survival that depend of the porphyrin concentration (1 and 5 mM) and light dose (27 and 54 Jcm-2). Irradiation for 7.5 min produced chromatin fragmentation characteristic of apoptosis, while the cells showed typical morphological changes of necrosis after 15 min irradiation. CP is localizated in the mitochondria.These results suggest that the porphyrin CP has interesting photobiological properties.