Abstract:
Low-dose 5-aminolevulinic acid photodynamic therapy (ALA-PDT) has been used to cope with skin photoaging, and is thought to involve DNA damage repair responses. However, it is still unknown how low-dose ALA-PDT regulates DNA damage repair to curb skin photoaging. We established a photoaging model using human dermal fibroblasts (HDFs) and rat skin. RNA-sequencing (RNA-seq) analysis was conducted to identify differentially expressed genes (DEGs) in HDFs before and after low-dose ALA-PDT treatment, followed by bioinformatics analysis. Senescence-associated β-galactosidase (SA-β-gal) staining was employed to assess skin aging-related manifestations and Western blotting to evaluate the expression of associated proteins. A comet assay was used to detect cellular DNA damage, while immunofluorescence to examine the expression of 8-hydroxy-2\'-deoxyguanosine (8-oxo-dG) in cells and skin tissues. In both in vivo and in vitro models, low-dose ALA-PDT alleviated the manifestations of ultraviolet B (UVB)-induced skin photoaging. Low-dose ALA-PDT significantly reduced DNA damage in photoaged HDFs. Furthermore, low-dose ALA-PDT accelerated the clearance of the photoproduct 8-oxo-dG in photoaged HDFs and superficial dermis of photoaged rat skin. RNA-seq analysis suggested that low-dose ALA-PDT upregulated the expression of key genes in the base excision repair (BER) pathway. Further functional validation showed that inhibition on BER expression by using UPF1069 significantly suppressed SA-β-gal activity, G2/M phase ratio, expression of aging-associated proteins P16, P21, P53, and MUTYH proteins, as well as clearance of the photoproduct 8-oxo-dG in photoaged HDFs. Low-dose ALA-PDT exerts anti-photoaging effects by activating the BER signalling pathway.
摘要:
低剂量5-氨基乙酰丙酸光动力疗法(ALA-PDT)已用于应对皮肤光老化,并被认为涉及DNA损伤修复反应。然而,目前尚不清楚低剂量ALA-PDT如何调节DNA损伤修复以抑制皮肤光老化.我们使用人真皮成纤维细胞(HDFs)和大鼠皮肤建立了光老化模型。进行RNA测序(RNA-seq)分析以鉴定低剂量ALA-PDT治疗前后HDF中的差异表达基因(DEG)。其次是生物信息学分析。采用衰老相关β-半乳糖苷酶(SA-β-gal)染色评估皮肤衰老相关表现,并采用Western印迹评估相关蛋白的表达。彗星试验用于检测细胞DNA损伤,同时免疫荧光检测8-羟基-2'-脱氧鸟苷(8-oxo-dG)在细胞和皮肤组织中的表达。在体内和体外模型中,低剂量ALA-PDT减轻了紫外线B(UVB)引起的皮肤光老化的表现。低剂量ALA-PDT可显着降低光老化HDFs中的DNA损伤。此外,低剂量ALA-PDT加速了光老化HDFs和光老化大鼠皮肤浅层真皮中光产物8-oxo-dG的清除。RNA-seq分析表明,低剂量ALA-PDT上调碱基切除修复(BER)途径中关键基因的表达。进一步的功能验证表明,使用UPF1069对BER表达的抑制显着抑制了SA-β-gal活性,G2/M相比,衰老相关蛋白P16、P21、P53和MUTYH蛋白的表达,以及光老化HDF中光产物8-oxo-dG的清除。低剂量ALA-PDT通过激活BER信号通路发挥抗光老化作用。