Figure 4.

Knockdown of the TRPV1 gene attenuates the effects of blue light on cell proliferation. HaCaT cells were transfected with TRPV1 siRNA, followed by incubation for 16 h. (a) The transfected cells were irradiated using the indicated intensity of blue light with a wavelength of 470–480 nm and further incubated for 24 h. The cells were subjected to cell proliferation testing using cell counting kit-8 assay and Western blotting analysis for assessing the EGFR, TRPV1, or β-actin levels. Results were obtained from at least three independent experiments, and the values represent the mean ± SEM. p values were obtained by one-way ANOVA. ^∗p < 0.05 vs. the untreated control, ^op < 0.05 vs. the blue light-irradiated control. (b) HaCaT cells were treated with capsazepine (CPZ), a TRPV1 antagonist. After 30 minutes, they were washed with PBS and irradiated with the indicated intensity of blue light. After 24 hours, the cells were subjected to cell proliferation testing using cell counting kit-8 assay. Results were obtained from at least three independent experiments, and the values represent the mean ± SEM. p values were obtained by one-way ANOVA. ^∗p < 0.05 vs. the blue light-irradiated control.