Development of Novel Photosensitizer Using the Buddleja officinalis Extract for Head and Neck Cancer

Figure 3

Determination of intracellular localization of BO extract and ROS generation and morphological changes induced by treatment with BO extract and 625 nm LED irradiation. (a) Photomicrographs showing the intracellular fluorescence of BO at various incubation times in the FaDu cell line. Confocal microscopy revealed that BO-PDT was localized in the cell membrane and the cytoplasm, excluding the cell nucleus. The fluorescence intensity in stained cells increased during 1–4 h. (b) The fluorescence intensity of BO extract evaluated with Image J. (c) DCF-DA assay, performed to compare ROS levels in FaDu cells treated with BO extract and those treated with hematoporphyrin (HP) (upper panel). The ROS levels after BO-PDT were significantly higher than after HP-PDT. The cells were subsequently stained with Diff-Quick staining (Lower panel) and examined for morphological changes after BO-PDT. The red arrow indicates cell undergoing apoptosis. (d) The fluorescence intensity of DCF-DA in the cells evaluated with Image J. Nontreated condition versus BO: # P < 0.05; ## P < 0.001; BO versus BO-PDT: P < 0.05; P < 0.01.

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