Cellular heat acclimation regulates cell growth, cell morphology, mitogen-activated protein kinase activation, and expression of aquaporins in mouse fibroblast cells.
The heat shock response has been extensively studied by a number of investigators to understand the molecular mechanism underlying the cellular response to severe heat stress (higher than 42°C). But, body or tissue temperature increases by only a few degrees Celsius during physiological events. Therefore, the physiological cellular response to mild heat stress rather than severe heat stress is likely to be more important. Repeated exposure to hyperthermia for consecutive 5 days induces heat acclimation which is an adaptive physiological process in humans and animals. However, thus far, the effect of continuous exposure to heat stress on cells has not been fully evaluated. In this study, we investigated an adaptive physiological process that is induced in culture cells by continuous exposure to mild heat stress for 5 days. Exposure to heat activated p38-mitogen-activated protein kinase; inhibited cell growth without apoptosis; and increased the levels of HSPs and HSF-1 in mouse fibroblast cells. Interestingly, exposure to heat regulated the expression of aquaporins and induced morphological change. In a physiological sense, these results suggested that continuous exposure to mild heat stress for 5 days, in which heat acclimation is attained in humans and animals, might induce molecular adaptation to heat in cells.
Department of Physiology, Graduate School of Medical Science, Kanazawa University, 13-1 Takara-machi, Kanazawa, Ichikawa, Japan. ns@med.kanazawa-u.ac.jp
Naotoshi
N
Sugimoto
Osamu
O
Shido
Kentaro
K
Matsuzaki
Takako
T
Ohno-Shosaku
Yoshiaki
Y
Hitomi
Masao
M
Tanaka
Toshioki
T
Sawaki
Yoshimasa
Y
Fujita
Takanori
T
Kawanami
Yasushi
Y
Masaki
Toshiro
T
Okazaki
Hiroyuki
H
Nakamura
Shoichi
S
Koizumi
Akihiro
A
Yachie
Hisanori
H
Umehara
D000818:Animals; D020346:Aquaporins / Q000378:metabolism*; D049109:Cell Proliferation; D004268:DNA-Binding Proteins / Q000378:metabolism; D005347:Fibroblasts / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D018841:HSP90 Heat-Shock Proteins / Q000378:metabolism; D000076249:Heat Shock Transcription Factors; D006358:Hot Temperature; D006801:Humans; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D041681:NIH 3T3 Cells; D013312:Stress, Physiological; D014157:Transcription Factors / Q000378:metabolism; D015854:Up-Regulation; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
D020346:Aquaporins; D004268:DNA-Binding Proteins; D018840:HSP70 Heat-Shock Proteins; D018841:HSP90 Heat-Shock Proteins; D000076249:Heat Shock Transcription Factors; C490017:Hsf1 protein, mouse; D014157:Transcription Factors; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases