Evaluation of photodynamic therapy on fibroblast viability and cytokine production

The aim of this study was to evaluate the effects of photodynamic therapy with curcumin (PDT) comparatively to 5% sodium hypochlorite (NaOCl) and saline solution on cell viability and cytokine (IL-1β and IL-6) production by mouse fibroblasts.

Sixty seconds of pre-irradiation time with curcumin 500mg/L and Led wavelength (λ) 480nm, 72Jcm(2), for 300s was used for PDT. Solutions were diluted in culture medium DMEM (1×10(4) cells) and placed into 24-well cell culture plates with mouse fibroblasts L-929. Culture medium was used as control. After 6, 24 and 48h, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay (MTT) was used to evaluate the cell viability and the supernatant was collected for cytokine evaluation using enzyme-linked immunosorbent assay (ELISA). The results were statistically analyzed by ANOVA and BonFerroni correction (p<0.05) for MTT and Kruskal-Wallis test and Dunn (p<0.05) for ELISA.

PDT and saline solution presented low cytotoxic effect similar to the control group (p>0.05) while 5% NaOCl was more cytotoxic than PDT (p<0.05) in all periods of time. All materials similarly expressed IL-1β and IL-6 regardless to the experimental period (p<0.05).

PDT with curcumin was not cytotoxic to L929 fibroblasts differently from 5% NaOCl. In all groups occurred similar expression of IL-1β and IL-6.