Abstract:

Yi Fei, Maya Valeska Gozali, Zhang Jia′an, Zhou Bingrong, Luo Dan, Zhang Lichao, Wang Shen, Liu Juan, Wu Hongjin. Department of Dermatology, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China Corresponding authors: Luo Dan, Email: daniluo2005@163.com; Zhou Bingrong, Email: bingrong.2002@163.com 【Abstract】 Objective To evaluate the inhibitory effects of aminolevulinic acid-based photodynamic therapy （ALA-PDT） on fibroblast growth factor 10 （FGF-10）-induced excessive cornification and proliferation of HaCaT cells, and to explore their mechanisms. Methods Cultured HaCaT cells were randomly divided into 4 groups: blank control group receiving no treatment, FGF-10 group treated with FGF-10 for 24 hours, ALA-PDT group pretreated with ALA for 24 hours followed by 635-nm red laser radiation, FGF-10 + ALA-PDT group pretreated with FGF-10 for 24 hours and then with ALA for another 24 hours followed by 635-nm red laser radiation. After additional culture for 24 hours, cell counting kit-8 （CCK8） assay was performed to evaluate the proliferative activity of HaCaT cells, Western blot analysis to detect the protein expressions of keratin 1 （K1）, K6, K16 and keratinocyte growth factor receptor （KGFR） in cells, enzyme-linked immunosorbent assay （ELISA） to measure the expression of interleukin 1α （IL-1α） in the culture supernatant of cells, and an immunofluorescence assay to analyze the protein expressions of KGFR and K6 in cells. Statistical analysis was carried out by using factorial analysis of variance （ANOVA） and one-way ANOVA. Results As factorial ANOVA showed, there was no interaction effect on the proliferation of HaCaT cells between ALA-PDT and FGF-10 （F = 1.369, P = 0.276）, and main effect analysis revealed that the proliferation of HaCaT cells was accelerated by FGF-10 （F = 20.853, P < 0.05）, but inhibited by ALA-PDT （F = 24.822, P < 0.05）. The proliferative activity （expressed as the absorbence value at 490 nm） of HaCaT cells was significantly increased in the FGF-10 group （1.233 ± 0.099）, but significantly decreased in the ALA-PDT group （0.718 ± 0.107） compared with the blank control group （0.924 ± 0.024, both P < 0.05）, and in the FGF-10 + ALA-PDT group （0.901 ± 0.014, P < 0.05） compared with the FGF-10 group. Similarly, the protein expressions of K1, K6, K16, KGFR were significantly upregulated in the FGF-10 group, but significantly downregulated in the ALA-PDT group compared with the blank control group （all P < 0.05）, and in the FGF-10 + ALA-PDT group compared with the FGF-10 group （all P < 0.05）. The supernatant level of IL-1α was significantly elevated in the FGF-10 group （P < 0.05）, but showed no significant changes in the ALA-PDT group compared with the blank control group （P = 0.467）. Furthermore, the immunofluorescence intensities of K6 and KGFR in HaCaT cells were significantly enhanced in the FGF-10 group （both P<0.05）, but reduced in the ALA-PDT group compared with the blank control group （both P < 0.05）, and in the FGF-10 + ALA-PDT group compared with the FGF-10 group （both P < 0.05）. Conclusion ALA-PDT can inhibit the FGF-10-induced excessive cornification and proliferation of HaCaT cells, likely by down-regulating K1, K6, K16, KGFR and IL-1α.