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Hsp72 and Hsp90? mRNA transcription is characterised by large, sustained changes in core temperature during heat acclimation.

ABSTRACT: Increased intracellular heat shock protein-72 (Hsp72) and heat shock protein-90? (Hsp90?) have been implicated as important components of acquired thermotolerance, providing cytoprotection during stress. This experiment determined the physiological responses characterising increases in Hsp72 and Hsp90? mRNA on the first and tenth day of 90-min heat acclimation (in 40.2 °C, 41.0 % relative humidity (RH)) or equivalent normothermic training (in 20 °C, 29 % RH). Pearson's product-moment correlation and stepwise multiple regression were performed to determine relationships between physiological [e.g. (Trec, sweat rate (SR) and heart rate (HR)] and training variables (exercise duration, exercise intensity, work done), and the leukocyte Hsp72 and Hsp90? mRNA responses via reverse transcription quantitative polymerase chain reaction (RT-QPCR) (n = 15). Significant (p < 0.05) correlations existed between increased Hsp72 and Hsp90? mRNA (r = 0.879). Increased core temperature was the most important criteria for gene transcription with ?Trec (r = 0.714), SR (r = 0.709), Trecfinal45 (r = 0.682), area under the curve where Trec ? 38.5 °C (AUC38.5 °C; r = 0.678), peak Trec (r = 0.661), duration Trec ? 38.5 °C (r = 0.650) and ?HR (r = 0.511) each demonstrating a significant (p < 0.05) correlation with the increase in Hsp72 mRNA. The Trec AUC38.5 °C (r = 0.729), ?Trec (r = 0.691), peak Trec (r = 0.680), Trecfinal45 (r = 0.678), SR (r = 0.660), duration Trec ? 38.5 °C (r = 0.629), the rate of change in Trec (r = 0.600) and ?HR (r = 0.531) were the strongest correlate with the increase in Hsp90? mRNA. Multiple regression improved the model for Hsp90? mRNA only, when Trec AUC38.5 °C and SR were combined. Training variables showed insignificant (p > 0.05) weak (r < 0.300) relationships with Hsp72 and Hsp90? mRNA. Hsp72 and Hsp90? mRNA correlates were comparable on the first and tenth day. When transcription of the related Hsp72 and Hsp90? mRNA is important, protocols should rapidly induce large, prolonged changes in core temperature.

SUBMITTER: Gibson OR

PROVIDER: S-EPMC5083671 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Hsp72 and Hsp90α mRNA transcription is characterised by large, sustained changes in core temperature during heat acclimation.

Gibson Oliver R OR Tuttle James A JA Watt Peter W PW Maxwell Neil S NS Taylor Lee L

Cell stress & chaperones 20160811 6

Increased intracellular heat shock protein-72 (Hsp72) and heat shock protein-90α (Hsp90α) have been implicated as important components of acquired thermotolerance, providing cytoprotection during stress. This experiment determined the physiological responses characterising increases in Hsp72 and Hsp90α mRNA on the first and tenth day of 90-min heat acclimation (in 40.2 °C, 41.0 % relative humidity (RH)) or equivalent normothermic training (in 20 °C, 29 % RH). Pearson's product-moment correlation ...[more]

PMID: 27511024

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Dataset Information

Hsp72 and Hsp90? mRNA transcription is characterised by large, sustained changes in core temperature during heat acclimation.

Publications

Hsp72 and Hsp90α mRNA transcription is characterised by large, sustained changes in core temperature during heat acclimation.

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