title: Long-term heat exposure prevents hypoxia-induced apoptosis in mouse fibroblast cells.
abstract: Long-term continuous exposure to high ambient temperatures induces complete heat acclimation in humans and animals. However, to date, the effects of long-term exposure to heat stress on cells have not been fully evaluated. In this study, we investigated an adaptive physiological process induced in culture cells by continuous exposure to mild heat stress for 60 days. The results of this investigation provide evidence that after long-term heat acclimation in cells, (1) heat shock protein levels are increased, (2) hypoxia inducible factor-1α (HIF-1α) expression is upregulated, and (3) heat shock-induced and hypoxia-induced apoptoses are attenuated. These results suggest that the hypoxia response pathway is an intrinsic part of the heat acclimation repertoire and that the HIF-1 pathway following long-term heat acclimation induces cells with cross tolerance against hypoxia.
authors.affiliation: Department of Physiology, Graduate School of Medical Science, Kanazawa University, 13-1 Takara-machi, Kanazawa, Ishikawa, 920-8640, Japan, ns@med.kanazawa-u.ac.jp.
authors.forename: Naotoshi
authors.initials: N
authors.lastname: Sugimoto
authors.forename: Osamu
authors.initials: O
authors.lastname: Shido
authors.forename: Kentaro
authors.initials: K
authors.lastname: Matsuzaki
authors.forename: Masanori
authors.initials: M
authors.lastname: Katakura
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Hitomi
authors.forename: Masao
authors.initials: M
authors.lastname: Tanaka
authors.forename: Toshioki
authors.initials: T
authors.lastname: Sawaki
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Fujita
authors.forename: Takafumi
authors.initials: T
authors.lastname: Kawanami
authors.forename: Yasufumi
authors.initials: Y
authors.lastname: Masaki
authors.forename: Toshiro
authors.initials: T
authors.lastname: Okazaki
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakamura
authors.forename: Shoichi
authors.initials: S
authors.lastname: Koizumi
authors.forename: Akihiro
authors.initials: A
authors.lastname: Yachie
authors.forename: Hisanori
authors.initials: H
authors.lastname: Umehara
mesh_terms: D000064:Acclimatization; D000818:Animals; D017209:Apoptosis; D015687:Cell Hypoxia; D004268:DNA-Binding Proteins / Q000378:metabolism; D004789:Enzyme Activation; D005347:Fibroblasts / Q000166:cytology* / Q000378:metabolism; D000076249:Heat Shock Transcription Factors; D006360:Heat-Shock Proteins / Q000378:metabolism; D018869:Heat-Shock Response; D051379:Mice; D041681:NIH 3T3 Cells; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; D000076249:Heat Shock Transcription Factors; D006360:Heat-Shock Proteins; C490017:Hsf1 protein, mouse; D014157:Transcription Factors; D048051:p38 Mitogen-Activated Protein Kinases