title: miR-377 induces senescence in human skin fibroblasts by targeting DNA methyltransferase 1.
abstract: Skin aging is a complicated physiological process and epigenetic feature, including microRNA-mediated regulation and DNA methylation, have been shown to contribute to this process. DNA methylation is regulated by DNA methyltransferase, of which DNA methyltransferase 1 (DNMT1) is the most abundantly known. But evidence supporting its role in skin aging remains scarce, and no report regards its specifical upstream-regulating molecules in the process of skin aging so far. Here, we found that DNMT1 expression was markedly higher in young human skin fibroblasts (HSFs) than that in passage-aged HSFs, and DNMT1 knockdown significantly induced the senescence phenotype in young HSFs. We predicted the upstream miRNAs which could regulate DNMT1 with miRNA databases and found miR-377 had high homology with a sequence in the 3'-UTR of human DNMT1 mRNA. We confirmed that miR-377 was a potential regulator of DNMT1 by luciferase reporter assays. miR-377 expression in passage-aged HSFs was markedly higher than that in the young HSFs. miR-377 overexpression promoted senescence in young HSFs, and inhibition of miR-377 reduced senescence in passage-aged HSFs. Moreover, these functions were mediated by targeting DNMT1. Microfluidic PCR and next-generation bisulfite sequencing of 24 senescent-associated genes' promoters revealed alterations of the promoter methylation levels of FoxD3, p53, and UTF1 in HSFs treated with miR-377 mimics or inhibitors. We also verified that the miR-377-mediated changes in p53 expression could be reversed by regulation of DNMT1 in HSFs. Similarly, there was a negative correlation between miR-377 and DNMT1 expression in young and photoaged HSFs, HSFs, or skin tissues from UV-unexposed areas of different aged donors. Our results highlight a novel role for miR-377-DNMT1-p53 axis in HSF senescence. These findings shed new light on the mechanisms of skin aging and identify future opportunities for its therapeutic prevention.
authors.affiliation: Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China.|Key Laboratory of Organ injury, Ageing and Regenerative Medicine of Hunan Province, Changsha, China.
authors.forename: Hong-Fu
authors.initials: HF
authors.lastname: Xie
authors.affiliation: Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China.|Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Ying-Zi
authors.initials: YZ
authors.lastname: Liu
authors.affiliation: Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China.|Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Du
authors.affiliation: Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China.|Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Ben
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China.|Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Meng-Ting
authors.initials: MT
authors.lastname: Chen
authors.affiliation: Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China.|State Key Laboratory of Medical Genetics, Central South University, Changsha, Hunan, China.
authors.forename: Yi-Ya
authors.initials: YY
authors.lastname: Zhang
authors.affiliation: Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China.|Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Zhi-Li
authors.initials: ZL
authors.lastname: Deng
authors.affiliation: Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China.|Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha, China.|State Key Laboratory of Medical Genetics, Central South University, Changsha, Hunan, China.|Key Laboratory of Organ injury, Ageing and Regenerative Medicine of Hunan Province, Changsha, China.
authors.forename: Ji
authors.initials: J
authors.lastname: Li
mesh_terms: D000375:Aging / Q000235:genetics*; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics*; D019175:DNA Methylation / Q000235:genetics*; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D005786:Gene Expression Regulation / Q000235:genetics; D055785:Gene Knockdown Techniques; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D011401:Promoter Regions, Genetic; D012867:Skin / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*
chemical_list: C534063:MIRN377 microRNA, human; D035683:MicroRNAs; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; C000619380:DNMT1 protein, human