Photodynamic Effects of Pterin on HeLa Cells

M. PAULA DENOFRIO; CAROLINA LORENTE; THOMAS BREITENBACH; SONJA HATZ; FRANCO M. CABRERIZO *; ANDRÉS H. THOMAS*; PETER R. OGILBY*

PHOTOCHEMISTRY AND PHOTOBIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2011 vol. 87 p. 862 - 866

0031-8655

Pterins, heterocyclic compounds widespread in biological systems, participate in relevant biological processes and are able to act as photosensitizers. In the present study, we ascertained that 2-aminopteridin-4(3H)-one, or pterin (Ptr), is readily incorporated into and/or onto cervical cancer cells (HeLa) and that these cells die upon UV-A irradiation of Ptr. Cell death was assessed using two tests: (1) the Rhodamine 123 fluorescence assay for mitochondrial viability and (2) the Trypan Blue assay for membrane integrity.  The data suggest that, for Ptr-dependent photo-initiated cell death, events related to mitochondrial failure precede those associated with the failure of the cell membrane.