Efficacy of 670 nm Light Therapy to Protect against Photoreceptor Cell Death Is Dependent on the Severity of Damage

Figure 6

(a) The effect of 9 J/cm² of 670 nm light and light damage on H₂O₂ production in 661 W photoreceptor cells is shown here where bars represent the percentage change of H₂O₂ production when compared to nonlight damaged cells. Light damage significantly increased H₂O₂ production in the cells directly after one hour of light exposure. H₂O₂ production steadily increased amongst light damaged cells, both treated and nontreated, with increasing time under bright light conditions ( for all groups; each run consisted of duplicate wells for each group; “” denotes significance using one-way ANOVA with Tukey’s post hoc test, ; error bars represent SEM). (b) There was an increase in cell toxicity in light damaged (LD) cells, both treated and nontreated, when compared to nonlight damaged cells. 670 nm light did not significantly decrease cell toxicity in control or light damaged conditions ( for all groups; each run consisted of duplicate wells for each group; “” denotes significance using one-way ANOVA with Tukey’s post hoc test, ; error bars represent SEM).

(a) H₂O₂ production

(b) Cell toxicity