phytochlorin and Skin-Diseases

Photodynamic therapy (PDT) has been recommended as an alternative therapy for various diseases including microbial infection. Recently, we developed a new method for the preparation of highly pure chlorin e(6) (Ce(6)), which has been widely used as a second-generation photosensitizer. PDT using Ce(6) was very effective for inhibition of in vitro growth of several bacterial strains. To clarify a possibility for its clinical application, in this study, we examined in vitro and in vivo antimicrobial effects of Ce(6)-mediated PDT in mice model of skin infection of Staphylococcus aureus Xen29. Inhibition zone analysis and colony forming unit (CFU) count revealed that Ce(6)-mediated PDT inhibited effectively in vitro bacterial growth. In addition, biofilm formation ability of S. aureus Xen29 was decreased by Ce(6)-mediated PDT. In vivo experiment, mice receiving Ce(6)-mediated PDT exhibited less intensity of bioluminescent signal, showing significant inhibition of bacterial growth. Furthermore, in histopathological examination, marked neutrophilic infiltration and massive bacterial colonies were seen in control mice and mice receiving laser or Ce(6) alone, but not in mice treated with PDT. These results suggest that PDT using Ce(6) extracted by our new method can be clinically useful against bacterial infectious diseases.

Topics: Animals; Anti-Infective Agents; Chlorophyllides; Colony Count, Microbial; Disease Models, Animal; Male; Mice; Mice, Inbred BALB C; Photochemotherapy; Photosensitizing Agents; Porphyrins; Skin Diseases; Staphylococcal Infections; Staphylococcus aureus

Mono-L-aspartyl chlorin e6 (Talaporfin sodium) is a novel photosensitizer, and is currently being used in photodynamic therapy for various malignant tumors in combination with irradiation with a 664 nm laser. An interesting characteristic of Talaporfin sodium is that the skin photosensitivity after injection of this agent disappears faster than any other existing photosensitizers. This study examined the vascular events that occurred postirradiation in the chicken comb as a capillary malformation model after photosensitization with Talaporfin sodium.. A single intravenous bolus injections of Talaporfin sodium was administered to the chickens, and a 1 cm diameter area of the comb of each animal was irradiated with a 664 nm visible red laser. The gross changes in the chicken combs were recorded for 7-14 days after photodynamic therapy. For the histological examination, HE, PTAH and Azan stained sections were analyzed.. All treated chicken combs had blanched after photodynamic therapy. Microscopy demonstrated an absence of erythrocytes and the vessel lumina were obliterated, leaving the normal overlying epidermis completely intact. Concomitantly with selective destruction of the capillaries in the target area, moderate invasion of inflammatory cells and a slight increase in the stroma were observed.. In the chicken comb model, photodynamic therapy with Talaporfin sodium effectively achieved selective destruction of the microvasculature while leaving the epidermis intact. Our results strongly suggest that photodynamic therapy with Talaporfin sodium could be a feasible method to treat dermal hypervascular lesions.

Topics: Animals; Capillaries; Chickens; Chlorophyllides; Comb and Wattles; Erythrocytes; Inflammation; Male; Photochemotherapy; Photosensitizing Agents; Porphyrins; Port-Wine Stain; Radiation-Sensitizing Agents; Skin; Skin Diseases