Elevation of body temperature is an essential factor for exercise-increased extracellular heat shock protein 72 level in rat plasma

Abstract

This study examined whether the exercise-increased extracellular heat shock protein 72 (eHsp72) levels in rats was associated with body temperature elevation during exercise. In all, 26 female Sprague-Dawley rats (3 mo old) were assigned randomly to control (CON; n = 8), exercise under warm temperature (WEx; n = 9), or exercise under cold temperature (CEx; n = 9). The WEx and CEx were trained at 25 degrees C or 4 degrees C, respectively, for nine days using a treadmill. Before and immediately after the final exercise bout, the colonic temperatures were measured as an index of body temperature. The animals were subsequently anesthetized, and blood samples were collected and centrifuged. Plasma samples were obtained to assess their eHsp72 levels. Only the colonic temperature in WEx was increased significantly (P < 0.05) by exercise. The eHsp72 level in WEx was significantly higher (P < 0.05) than that of either the CON or CEx. However, no significant difference was found between CON and CEx. Regression analyses revealed that the eHsp72 level increased as a function of the body temperature. In another experiment, the eHsp72 level of animals with body temperature that was passively elevated through similar kinetics to those of the exercise was studied. Results of this experiment showed that mere body temperature elevation was insufficient to induce eHsp72 responses. Collectively, our results suggest that body temperature elevation during exercise is important for induction of exercise-increased eHsp72. In addition, the possible role of body temperature elevation is displayed when the exercise stressor is combined with it.

Increasing heat storage by wearing extra clothing during upper body exercise up-regulates heat shock protein 70 but does not modify the cytokine response

“…The present HSP70 data are in line with studies that document a magnified HSP70 response when performing exercise during additional heat stress (Ogura et al, 2008;Whitham et al, 2007). Even though factors other than temperature, Figure 3.…”

“…*Significantly different between conditions (P < 0.05). such as psychological stress, trauma or infection, can increase HSP70 plasma concentrations (Asea, 2006), temperature clamping or increased heat stress during exercise demonstrates the crucial role of cell temperature on HSP70 plasma concentration (Ogura et al, 2008;Whitham et al, 2007). This is also demonstrated by the proportional increase in extracellular HSP70 concentration with increasing temperature in peripheral blood mononuclear cells (Lancaster & Febbraio, 2005).…”

Attenuation of exercise-induced heat shock protein 72 expression blunts improvements in whole-body insulin resistance in rats with type 2 diabetes

“…In general, the primary factor that stimulates HSP72 induction is elevated cell temperature (Locke et al 1995). Ogura et al (2008) let animals exercise in a room at 25 or 4°C for 60 min and showed that the body temperature during exercise remained the same as that of before exercise (~38.5°C) at 4°C, whereas it increased to approximately 40.5°C at 25°C. They also reported that suppressing the increase in body temperature during exercise prevents increased HSP72 expression in the liver and skeletal muscle, suggesting that the increase in body temperature is an important factor for exercise-induced HSP72 expression.…”

Extracellular Hsp72 concentration relates to a minimum endogenous criteria during acute exercise-heat exposure

“…Research has identified extracellular changes in Hsp72 concentration within whole blood (Marshall et al 2006;Yamada et al 2007;Ogura et al 2008;Magalhães et al 2010;Périard et al 2012), and intracellular changes in total protein expression and/or gene transcription in monocytes and systemic tissue (McClung et al 2008;Selkirk et al 2009;Magalhães et al 2010;Amorim et al 2011) in response to thermal and exercise stress. Hsp72 binds with high affinity to the plasma membrane (Asea et al 2000) and up-regulates expression of pro-inflammatory cytokines, tumour necrosis factor-α, interleukin-1β and interleukin-6 in human monocytes.…”

“…Acknowledgements have been made by Ogura et al (2008) that body temperature elevation, and increased circulating Acknowledgments The authors would like to thank the volunteers for their participation in this investigation.…”