title: Induction of cellular senescence by secretory phospholipase A2 in human dermal fibroblasts through an ROS-mediated p53 pathway.
abstract: Secretory phospholipase A(2) (sPLA(2)) is involved in various cellular physiological and pathological responses, especially in inflammatory responses. Accumulating evidence suggests that inflammation is an underlying basis for the molecular alterations that link aging and age-related pathological processes. However, the involvement of sPLA(2) in cellular senescence is not clear. In this study, we found that sPLA(2) treatment induces cellular senescence in human dermal fibroblasts (HDFs), as confirmed by increases in senescence-associated beta-galactosidase activity, changes in cell morphology, and upregulation of p53/p21 protein levels. sPLA(2)-induced senescence was observed in p16-knockdown HDFs and p16-null mouse fibroblasts, but not in p53-knockdown HDFs and p53-null mouse fibroblasts. Treatment with sPLA(2) increases reactive oxygen species (ROS) production, and an antioxidant, N-acetylcysteine, inhibits sPLA(2)-induced cellular senescence. These results suggest that sPLA(2) has a role in cellular senescence in HDFs during inflammatory response by promoting ROS-dependent p53 activation and might therefore contribute to inflammatory disorders associated with aging.
authors.affiliation: Department of Biochemistry and Molecular Biology, Aging-associated Vascular Disease Research Center, College of Medicine, Yeungnam University, 317-1 Daemyung-Dong, Daegu 705-717, Republic of Korea.
authors.forename: Hyun Jung
authors.initials: HJ
authors.lastname: Kim
authors.forename: Kwang Seok
authors.initials: KS
authors.lastname: Kim
authors.forename: Si Hyung
authors.initials: SH
authors.lastname: Kim
authors.forename: Suk-Hwan
authors.initials: SH
authors.lastname: Baek
authors.forename: Hwa Young
authors.initials: HY
authors.lastname: Kim
authors.forename: ChuHee
authors.initials: C
authors.lastname: Lee
authors.forename: Jae-Ryong
authors.initials: JR
authors.lastname: Kim
mesh_terms: D000375:Aging / Q000502:physiology; D015153:Blotting, Western; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D016922:Cellular Senescence / Q000187:drug effects* / Q000502:physiology; D005260:Female; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism; D005434:Flow Cytometry; D006801:Humans; D008297:Male; D054467:Phospholipases A2 / Q000494:pharmacology*; D011336:Probability; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012680:Sensitivity and Specificity; D015398:Signal Transduction / Q000187:drug effects; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D017382:Reactive Oxygen Species; D016159:Tumor Suppressor Protein p53; D054467:Phospholipases A2