Open AccessBase excision repair but not DNA double‐strand break repair is impaired in aged human adipose‐derived stem cells
Author(s) -
Zhang Haiping,
Cai Bailian,
Geng Anke,
Tang Huanyin,
Zhang Wenjun,
Li Sheng,
Jiang Ying,
Tan Rong,
Wan Xiaoping,
Mao Zhiyong
Publication year - 2020
Publication title -
aging cell
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.103
H-Index - 140
eISSN - 1474-9726
pISSN - 1474-9718
DOI - 10.1111/acel.13062
Subject(s) - xrcc1 , biology , base excision repair , dna repair , homologous recombination , stem cell , somatic cell , non homologous end joining , dna damage , genetics , microbiology and biotechnology , cancer research , dna , gene , genotype , single nucleotide polymorphism
The decline in DNA repair capacity contributes to the age‐associated decrease in genome integrity in somatic cells of different species. However, due to the lack of clinical samples and appropriate tools for studying DNA repair, whether and how age‐associated changes in DNA repair result in a loss of genome integrity of human adult stem cells remains incompletely characterized. Here, we isolated 20 eyelid adipose‐derived stem cell (ADSC) lines from healthy individuals (young: 10 donors with ages ranging 17–25 years; old: 10 donors with ages ranging 50–59 years). Using these cell lines, we systematically compared the efficiency of base excision repair (BER) and two DNA double‐strand break (DSB) repair pathways—nonhomologous end joining (NHEJ) and homologous recombination (HR)—between the young and old groups. Surprisingly, we found that the efficiency of BER but not NHEJ or HR is impaired in aged human ADSCs, which is in contrast to previous findings that DSB repair declines with age in human fibroblasts. We also demonstrated that BER efficiency is negatively associated with tail moment, which reflects a loss of genome integrity in human ADSCs. Mechanistic studies indicated that at the protein level XRCC1, but not other BER factors, exhibited age‐associated decline. Overexpression of XRCC1 reversed the decline of BER efficiency and genome integrity, indicating that XRCC1 is a potential therapeutic target for stabilizing genomes in aged ADSCs.