TY - JOUR
T1 - Acute heat exposure protects against endothelial ischemia-reperfusion injury in aged humans
AU - Hemingway, Holden W.
AU - Richey, Rauchelle E.
AU - Moore, Amy M.
AU - Olivencia-Yurvati, Albert H.
AU - Kline, Geoffrey P.
AU - Romero, Steven A.
N1 - Funding Information:
Funding was provided by the National Institutes of Health Grants R01AG059314 and T32AG020494.
Publisher Copyright:
© 2022 American Physiological Society. All rights reserved.
PY - 2022/5
Y1 - 2022/5
N2 - Nonpharmacological therapies that protect against endothelial ischemia-reperfusion injury (I/R) remain limited in aged adults. Acute heat exposure protects against endothelial I/R injury in young adults, but its efficacy has never been explored in aged adults. Therefore, we tested the hypothesis that acute heat exposure would prevent the attenuation of endothelium-dependent vasodilation after I/R injury in aged adults. Nine (2 men, 69 ± 8 yr) aged adults were exposed to a thermoneutral control condition or whole body passive heating (water-perfused suit) sufficient to increase body core temperature by 1.2_C. Experiments were separated by at least 7 days. Heat exposure was always performed first to time match the thermoneutral control condition. Endothelium-dependent vasodilation was assessed via flow-mediated dilation of the brachial artery before (pre-I/R) and after I/R injury (post-I/R), which was induced by 20 min of arm ischemia followed by 20 min of reperfusion. Flow-mediated dilation was reduced following I/R injury for the thermoneutral control condition (pre-I/R, 4.5 ± 2.9% vs. post-I/R, 0.9 ± 2.8%, P < 0.01), but was well maintained with prior heat exposure (pre-I/R, 4.4 ± 2.8% vs. post-I/R, 3.5 ± 2.8%, P = 0.5). Taken together, acute heat exposure protects against endothelial I/R injury in aged adults. These results highlight the therapeutic potential of heat therapy to prevent endothelial dysfunction associated with I/R injury in aged adults who are most at risk for an ischemic event.
AB - Nonpharmacological therapies that protect against endothelial ischemia-reperfusion injury (I/R) remain limited in aged adults. Acute heat exposure protects against endothelial I/R injury in young adults, but its efficacy has never been explored in aged adults. Therefore, we tested the hypothesis that acute heat exposure would prevent the attenuation of endothelium-dependent vasodilation after I/R injury in aged adults. Nine (2 men, 69 ± 8 yr) aged adults were exposed to a thermoneutral control condition or whole body passive heating (water-perfused suit) sufficient to increase body core temperature by 1.2_C. Experiments were separated by at least 7 days. Heat exposure was always performed first to time match the thermoneutral control condition. Endothelium-dependent vasodilation was assessed via flow-mediated dilation of the brachial artery before (pre-I/R) and after I/R injury (post-I/R), which was induced by 20 min of arm ischemia followed by 20 min of reperfusion. Flow-mediated dilation was reduced following I/R injury for the thermoneutral control condition (pre-I/R, 4.5 ± 2.9% vs. post-I/R, 0.9 ± 2.8%, P < 0.01), but was well maintained with prior heat exposure (pre-I/R, 4.4 ± 2.8% vs. post-I/R, 3.5 ± 2.8%, P = 0.5). Taken together, acute heat exposure protects against endothelial I/R injury in aged adults. These results highlight the therapeutic potential of heat therapy to prevent endothelial dysfunction associated with I/R injury in aged adults who are most at risk for an ischemic event.
KW - aging
KW - endothelium
KW - flow-mediated dilation
KW - heat exposure
KW - ischemia-reperfusion injury
UR - http://www.scopus.com/inward/record.url?scp=85128244954&partnerID=8YFLogxK
U2 - 10.1152/ajpregu.00336.2021
DO - 10.1152/ajpregu.00336.2021
M3 - Article
C2 - 35200050
AN - SCOPUS:85128244954
SN - 0363-6119
VL - 322
SP - R360-R367
JO - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
JF - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
IS - 5
ER -