| Objectives: This study investegsted the antiapoptotic effect of PCF on UVB and UVB irradiated HaCat cells. Methods: HaCaT cells were irradiated with 1J/cm2 UVA and 15mJ/cm2 UVB together 1 hour after PCF addition. HaCat cells were divided into six groups: normal control group and UV groups (model, 0. 125%PCF, 0.25%PCF, 0. 5%PCF, 0. l%Vc). Apoptostic rates were firstly evaluated by MTT assay, further detected by flow cytometry. For better morphologic understanding, cellular ultrastructure was observed through transmission electron telescope. To identify possible antiapoptotic mechanism of PCF, p21 mRNA by in situ hybridization, Ca2+ and mitochondrial membrane potential by flow cytometry were detected. Comet assay was performed to examine whether PCF could resist DNA strand break which is the direct effect of UV i rradiation. Detections of SOD (superoxide dismutase), MDA (malond i ndehyde), GSH-PX (glulalhione peroxidase), T-AOC(total antioxidative capacity) and am p21 in medium with respective kits helped us to identify the antiapoptotic mechanism of PCF. Results:Our results showed that PCF significantly reduced the apoptotic rates of HaCaT cells, which was supported by observation of cellular ultrastructure. In agreement with this fact, PCF markedly increased the transcription of p21 mRNA. PCF also interestedlyreduced DNA fragments produced by UV irradiation. In disagreement with previous most reports, our results suggest that Ca2+ can decrease in apoptosis. To protect HaCaT cells, PCF greatly enhanced the antioxidative ability of HaCaT cells and reduecd intracellular ROS (reactive oxide species). In all assays PCF had the similar effect to vitamin C. Conclusions: PCF protects keratinocytes from UVB-induced apoptosis. its protective role is similar to vitamin C.
|
PDF Full Text Request