南京医科大学学报（自然科学版）2011，Vol.31Issue(9)：1289-1293,5.
UVB诱导下早衰人皮肤成纤维细胞中miR-34c及SIRT1表达的研究
Expression of senescence-associated miR-34c and SIRT1 in premature senescence of human skin fibroblasts induced by ultraviolet B
摘要
Abstract
Objective:To build the stress-induced premature senescence (SIPS) model with fibroblasts after repeated exposures to sub-toxic doses of ultraviolet B (UVB), and observe the expressions of senescence-associated biomarkers, senescence-associated signals including pS3,pl6,p21,sirtuin 1 (SIRTl),as well as senescence-associated miRNAs such as miR-34c. Methods:Skin fibroblasts were repeatedly exposed to UVB irradiation at a dose of 10 mJ/cm2 for S times. After 5 days of treatment,SA-β-Gal staining was performed to evaluate the senescence state,flow cytometry to analyze cell cycle,and real-time quantitative PCR to determine mRNA expression of senescence-associated signals including p53,pl6,p21,SIRTl and miR-34c. Western blot was performed to detect the expression of p53,p21,pl6 and SIRT1. Results;Compared with the control group,strong positive SA-β-Gal was observed in SIPS group, (94.72 ± 2.08)% in SIPS group compared with (8.13 ± 1.92)% in control group (P < 0.05). Most cells were arrested in G1 phase, (52.96 ± 1.76)% in control group compared with (77.31 ± 2.05)% in SIPS group (P < 0.05). Meanwhile,the expression of senescence-associated signals including p53,pl6,p21,SIRTl significantly increased after UVB exposure (0.74 ± 0.23,1.06 ± 0.23. 0.86 ± 0.13,0.74 ± 0.25 in control group while 1.84 ± 0.55,20.25 ± 2.34,16.7 ± 3.94,2.15 ± 0.22 in SIPS group,P< 0.05),so as to that of senescence-associated miRNAs such as miR-34c (0.93 ± 0.09 for miR-34c-3p and 1.03 ± 0.03 for miR-34c-5p in control group while 2.08 ± 0.19 for miR-34c-3p and 12.28 ± 1.64 for miR-34c-5p in SIPS group.P < 0.05). Western blot showed that p53,p21, pl6 and SIRT1 protein expression significantly increased in SIPS group compared with those in control group,and the difference was statistically significant(p < 0.05). Conclusion;The expression of miR-34c increases after repeated exposures to sub-toxic doses of UVB in skin fibroblasts,and it works as a positive feedback regulation to P53 while not inhibiting SIRT1.关键词
衰老/紫外线/成纤维细胞/SIRT1/miR-34cKey words
senescence/ultraviolet ray/fibroblasts/SIRT1/miR-34c分类
生物科学引用本文复制引用
郭娴菲,周炳荣,李巍,黄秋红,骆丹..UVB诱导下早衰人皮肤成纤维细胞中miR-34c及SIRT1表达的研究[J].南京医科大学学报（自然科学版）,2011,31(9):1289-1293,5.基金项目
国家自然科学基金(30771946) （30771946）
