title: Bioenergetics in chicken embryo fibroblast cells: evidence of lower proton leak in spontaneously immortalized chicken embryo fibroblasts compared to young and senescent primary chicken embryo fibroblast cells.
abstract: A spontaneously immortalized chicken embryo fibroblast (CEF) cell line (DF-1) is known to exhibit faster growth rate and greater sensitivity to oxidative stress compared to the primary parent CEF (pCEF1°) cells. Thus, major objectives of this study were to assess cell bioenergetics in pCEF1° and DF-1 cells under control conditions and in response to 4-hydroxy 2-nonenal (4-HNE) induced oxidative challenge. Cell bioenergetics were assessed by flux analysis of oxygen consumption rate (OCR). Under control conditions, DF-1 cells had higher OCR associated with ATP synthase activity and mitochondrial oxygen reserve capacity as well as lower OCR due to proton leak and non-mitochondrial cytochrome c oxidase activity. In response to 4-HNE (0 to 30 μM), DF-1 cells were more sensitive to oxidant challenge than both young (passage 8) and senescent (passage 19) pCEF1° cells. Both passages 8 and 19 pCEF1° cells exhibited higher proton leak in response to 4-HNE, but this was not observed in DF-1 cells. Inducible proton leak occurs by 4-HNE stimulated activation of uncoupling protein (UCP) and adenine nucleotide translocase (ANT). From mRNA expression data indicated that ANT and avian UCP were down-regulated and up-regulated, respectively, in DF-1 compared to pCEF1° cells. Thus, we hypothesize that DF-1 cells are unable to increase proton leak due to lower expression of ANT, but not avian UCP, and this inability to increase proton leak contributes to greater susceptibility to oxidative stress of DF-1 cells compared to pCEF1° cells.
authors.affiliation: Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA.
authors.forename: Kentu
authors.initials: K
authors.lastname: Lassiter
authors.affiliation: Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA.
authors.forename: Sami
authors.initials: S
authors.lastname: Dridi
authors.affiliation: Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA.
authors.forename: Alissa
authors.initials: A
authors.lastname: Piekarski
authors.affiliation: Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Greene
authors.affiliation: Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA.
authors.forename: Billy
authors.initials: B
authors.lastname: Hargis
authors.affiliation: Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA.
authors.forename: Byung-Whi
authors.initials: BW
authors.lastname: Kong
authors.affiliation: Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA. Electronic address: wbottje@uark.edu.
authors.forename: Walter
authors.initials: W
authors.lastname: Bottje
mesh_terms: D000818:Animals; D016922:Cellular Senescence / Q000235:genetics / Q000502:physiology*; D002642:Chick Embryo; D002645:Chickens; D004734:Energy Metabolism; D005347:Fibroblasts / Q000378:metabolism*; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism; D000226:Mitochondrial ADP, ATP Translocases / Q000378:metabolism; D010101:Oxygen Consumption; D061251:Primary Cell Culture; D011522:Protons; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D011522:Protons; D012333:RNA, Messenger; D000226:Mitochondrial ADP, ATP Translocases
keywords: 4-Hydroxy 2-nonenal; Adenine nucleotide translocase; Cell bioenergetics; Chicken embryo fibroblast cells; Flux analysis; Proton leak