Heat shock protein 90 does not contribute to cutaneous vasodilatation in older adults during heat stress

Microcirculation. 2019 Aug;26(6):e12541. doi: 10.1111/micc.12541. Epub 2019 Apr 29.


Objectives: Heat shock protein 90 (HSP90) contributes to cutaneous vasodilatation during exercise in the heat through nitric oxide (NO) synthase (NOS)-dependent mechanisms in young adults. We hypothesized that similar responses would be observed in older middle-aged adults.

Methods: In nineteen habitually active older middle-aged (56 ± 5 years) men (n = 9) and women (n = 10), cutaneous vascular conductance (CVC) was measured at four forearm skin sites continuously treated with (a) lactated Ringers solution (Control), (b) 10 mmol/L L-NAME (NOS inhibitor), (c) 178 μmol/L geldanamycin (HSP90 inhibitor), or (d) 10 mmol/L L-NAME and 178 μmol/L geldanamycin combined. Participants rested in an upright semi-recumbent position in the heat (35°C) for 70 minutes, followed by a 50-minute bout of moderate-intensity cycling (~55% peak oxygen uptake) and a 30-minute recovery period in the heat.

Results: In both men and women, we observed no significant effects of HSP90 inhibition on CVC throughout rest, exercise, and recovery in the heat (all P > 0.27). Conversely, NOS inhibition and dual NOS and HSP90 inhibition attenuated CVC relative to Control throughout the protocol (all P ≤ 0.05).

Conclusions: While NOS mediates cutaneous vasodilatation during rest, exercise, and recovery in the heat, HSP90 does not measurably influence this response in habitually active older middle-aged men or women under these conditions.

Keywords: NO; Thermoregulation; aging; chaperone; heat loss; microcirculation.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Female
  • Forearm / blood supply
  • Forearm / pathology
  • Forearm / physiopathology
  • HSP90 Heat-Shock Proteins / biosynthesis*
  • Heat Stress Disorders / drug therapy
  • Heat Stress Disorders / metabolism*
  • Heat Stress Disorders / pathology
  • Heat Stress Disorders / physiopathology*
  • Humans
  • Male
  • Middle Aged
  • Skin* / blood supply
  • Skin* / pathology
  • Skin* / physiopathology
  • Vasodilation*


  • HSP90 Heat-Shock Proteins