title: Acrylamide Induces Senescence in Macrophages through a Process Involving ATF3, ROS, p38/JNK, and a Telomerase-Independent Pathway.
abstract: Senescence, which is irreversible cell cycle arrest, is induced by various types of DNA damage, including genotoxic stress. Senescent cells show dysregulation of tumor suppressor genes and other regulators of cellular proliferation. Activating transcription factor 3 (ATF3) plays a pleiotropic role in biological processes through genotoxic stress. In this study, we examined the effects of acrylamide (ACR), a genotoxic carcinogen, on cellular senescence and the molecular mechanisms of ATF3 function in macrophages. Treatment of macrophages with ACR at low concentrations (<1.0 mM) resulted in senescence-like morphology and an increase in senescence-associated β-galactosidase (SA-β-gal) activity. Exposure of macrophages to ACR led to stress-induced, telomerase-independent senescence. In addition, ACR treatment for 1, 3, or 5 days showed a concentration-dependent increase in ATF3 expression and G0/G1 phase arrest. To better understand the role of ATF3 in controlling the senescence response to ACR, SA-β-gal activity was examined using ATF3 knockdown and overexpression. ACR-mediated senescence was significantly decreased by knockdown of ATF3, whereas it was increased with ATF3 overexpression. We found that ATF3 regulated p53 and p21 levels. ATF3 also played an important role in regulating intracellular reactive oxygen species (ROS) production in response to ACR treatment. Moreover, phosphorylation of p38 and JNK kinases, which were activated during ATF3-mediated senescence, was observed in ACR-treated macrophages. Taken together, these results suggest that ATF3 contributes to ACR-induced senescence by enhancing ROS production, activating p38 and JNK kinases, and promoting the ATF3-dependent expression of p53, resulting in regulation of cellular senescence in macrophages.
authors.affiliation: School of Pharmacy, Sungkyunkwan University , Suwon, Kyunggi-do, 440-746, Republic of Korea.
authors.forename: Kyung-Ho
authors.initials: KH
authors.lastname: Kim
authors.affiliation: School of Pharmacy, Sungkyunkwan University , Suwon, Kyunggi-do, 440-746, Republic of Korea.
authors.forename: Bongkyun
authors.initials: B
authors.lastname: Park
authors.affiliation: School of Pharmacy, Sungkyunkwan University , Suwon, Kyunggi-do, 440-746, Republic of Korea.
authors.forename: Dong-Kwon
authors.initials: DK
authors.lastname: Rhee
authors.affiliation: School of Pharmacy, Sungkyunkwan University , Suwon, Kyunggi-do, 440-746, Republic of Korea.
authors.forename: Suhkneung
authors.initials: S
authors.lastname: Pyo
mesh_terms: D020106:Acrylamide / Q000633:toxicity*; D051700:Activating Transcription Factor 3 / Q000235:genetics / Q000378:metabolism; D000818:Animals; D002273:Carcinogens / Q000633:toxicity*; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D016922:Cellular Senescence / Q000187:drug effects* / Q000502:physiology; D005347:Fibroblasts; D048670:MAP Kinase Kinase 4 / Q000378:metabolism; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction; D019098:Telomerase; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D051700:Activating Transcription Factor 3; C103002:Atf3 protein, mouse; D002273:Carcinogens; D017382:Reactive Oxygen Species; D016159:Tumor Suppressor Protein p53; D020106:Acrylamide; D048051:p38 Mitogen-Activated Protein Kinases; D048670:MAP Kinase Kinase 4; D019098:Telomerase