scholarly journals Heat shock protein 90 modulates cutaneous vasodilation during an exercise‐heat stress, but not during passive whole‐body heating in young women

2020 ◽  
Vol 8 (16) ◽  
Author(s):  
Gregory W. McGarr ◽  
Naoto Fujii ◽  
Madison D. Schmidt ◽  
Caroline M. Muia ◽  
Glen P. Kenny
2017 ◽  
Vol 123 (4) ◽  
pp. 844-850 ◽  
Author(s):  
Naoto Fujii ◽  
Sarah Y. Zhang ◽  
Brendan D. McNeely ◽  
Takeshi Nishiyasu ◽  
Glen P. Kenny

While the mechanisms underlying the control of cutaneous vasodilation have been extensively studied, there remains a lack of understanding of the different factors that may modulate cutaneous perfusion during an exercise-induced heat stress. We evaluated the hypothesis that heat shock protein 90 (HSP90) contributes to the heat loss response of cutaneous vasodilation via the activation of nitric oxide synthase (NOS) during exercise in the heat. In 11 young males (25 ± 5 yr), cutaneous vascular conductance (CVC) was measured at four forearm skin sites that were continuously treated with 1) lactated Ringer solution (control), 2) NOS inhibition with 10 mM NG-nitro-l-arginine methyl ester (l-NAME), 3) HSP90 inhibition with 178 μM geldanamycin, or 4) a combination of 10 mM l-NAME and 178 μM geldanamycin. Participants rested in a moderate heat stress (35°C) condition for 70 min. Thereafter, they performed a 50-min bout of moderate-intensity cycling (~52% V̇o2peak) followed by a 30-min recovery period. We showed that NOS inhibition attenuated CVC (~40–50%) relative to the control site during pre- and postexercise rest in the heat ( P ≤ 0.05); however, no effect of HSP90 inhibition was observed ( P > 0.05). During exercise, we observed an attenuation of CVC with the separate inhibition of NOS (~40–50%) and HSP90 (~15–20%) compared with control (both P ≤ 0.05). However, the effect of HSP90 inhibition was absent in the presence of the coinhibition of NOS ( P > 0.05). We show that HSP90 contributes to cutaneous vasodilation in young men exposed to the heat albeit during exercise only. We also show that the HSP90 contribution is due to NOS-dependent mechanisms. NEW & NOTEWORTHY We show that heat shock protein 90 functionally contributes to the heat loss response of cutaneous vasodilation during exercise in the heat, and this response is mediated through the activation of nitric oxide synthase. Therefore, interventions that may activate heat shock protein 90 may facilitate an increase in heat dissipation through an augmentation of cutaneous perfusion. In turn, this may attenuate or reduce the increase in core temperature and therefore the level of heat strain.


2019 ◽  
Vol 26 (6) ◽  
Author(s):  
Naoto Fujii ◽  
Gregory W. McGarr ◽  
Kion Hatam ◽  
Nithila Chandran ◽  
Caroline M. Muia ◽  
...  

2012 ◽  
Vol 58 (6) ◽  
pp. 662-672 ◽  
Author(s):  
V.A. Kudryavtsev ◽  
Y.M. Makarova ◽  
A.E. Kabakov

Effects of inhibitors of the heat shock protein 90 (HSP90) chaperone activity and inhibitors of the heat shock protein (HSP) expression on sensitivity of HeLa tumor cells to hyperthermia were studied. It was found that nanomolar concentrations of inhibitors of the HSP90 activity (17AAG or radicicol) slowed down chaperone-dependent reactivation of a thermo-labile reporter (luciferase) in heat-stressed HeLa cells and slightly enhanced their death following incubation for 60 min at 43°C. Herein, the inhibitors of HSP90 activity stimulated de novo induction of additional chaperones (HSP70 and HSP27) that significantly increased the intracellular HSP levels. If the cells were treated with 17AAG or radicicol along with an inhibitor of the HSP induction (e.g. quercetin or triptolid, or NZ28), this fully prevented the increase in intracellular chaperone levels resulting from the inhibition of HSP90 activity and subsequent heating. Importantly, in the case of conjunction of all the three treatments (an inhibitor of the HSP90 activity + an inhibitor of the HSP induction + 43°C for 60 min), the reporter reactivation was retarded yet stronger while the cell death was sharply (2-3-fold) enhanced. Such an enhancement of the cytotoxicity appears to occur owing to the "chaperone deficiency" when prior to heat stress both the functional activity of constitutive HSP90 and the expression of additional (inducible) chaperones are blocked in the cells.


2002 ◽  
Vol 92 (6) ◽  
pp. 2600-2607 ◽  
Author(s):  
Sherry d. Fleming ◽  
Benjamin W. Starnes ◽  
Juliann G. Kiang ◽  
Alexander Stojadinovic ◽  
George C. Tsokos ◽  
...  

Prior induction of heat shock protein 70 (HSP70) protects against ischemia-reperfusion (I/R) mucosal injury, but the ability of HSP70 to affect I/R-induced alterations in epithelial cell function is unknown. Rats subjected to whole body hyperthermia (41.5–42°C for 6 min) increased HSP70 and heat shock factor 1 mRNA expression, reaching a maximum 2 h after heat stress and declining thereafter. HSP70 production was maximally elevated at 4 h after heat stress and remained elevated until after 12 h. Heat stress alone had no effect on mucosal function except to enhance secretion in response to ACh. Heat stress provided complete morphological protection against I/R-induced mucosal injury but did not confer a similar protection against I/R-induced decreases in mucosal resistance, sodium-linked glucose absorption, or tachykinin-mediated chloride secretion. Heat stress, however, attenuated the I/R-induced suppression of ACh response, and this effect was dependent on enteric nerves. Thus induction of heat shock protein 70 is associated with the preservation of mucosal architecture and attenuation of some specific functional alterations induced by I/R.


2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Roy M. Salgado ◽  
Ailish C. White ◽  
Suzanne M. Schneider ◽  
Christine M. Mermier

Heat shock protein 90 (HSP90) is a member of a family of molecular chaperone proteins which can be upregulated by various stressors including heat stress leading to increases in HSP90 protein expression. Its primary functions include (1) renaturing and denaturing of damaged proteins caused by heat stress and (2) interacting with client proteins to induce cell signaling for gene expression. The latter function is of interest because, in cancer cells, HSP90 has been reported to interact with the transcription hypoxic-inducible factor 1α (HIF1α). In a normoxic environment, HIF1α is degraded and therefore has limited physiological function. In contrast, in a hypoxic environment, stabilized HIF1α acts to promote erythropoiesis and angiogenesis. Since HSP90 interacts with HIF1α, and HSP90 can be upregulated from heat acclimation in humans, we present a proposal that heat acclimation can mimic molecular adaptations to those of altitude exposure. Specifically, we propose that heat acclimation increases HSP90 which then stabilizes HIF1α in a normoxic environment. This has many implications since HIF1α regulates red blood cell and vasculature formation. In this paper we will discuss (1) the functional roles of HSP90 and HIF1α, (2) the interaction between HSP90 and other client proteins including HIF1α, and (3) results from in vitro studies that may suggest how the relationship between HSP90 and HIF1α might be applied to individuals preparing to make altitude sojourns.


2020 ◽  
Vol 156 ◽  
pp. 522-530
Author(s):  
Natália G. Quel ◽  
Glaucia M.S. Pinheiro ◽  
Luiz Fernando de C. Rodrigues ◽  
Leandro R.S. Barbosa ◽  
Walid A. Houry ◽  
...  

2018 ◽  
Vol 32 (S1) ◽  
Author(s):  
Gregory W. McGarr ◽  
Naoto Fujii ◽  
Kion Hatam ◽  
Nithila Chandran ◽  
Glen P. Kenny

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