{"title":"GH and IGF-1 in skin interstitial fluid and blood are associated with heat loss responses in exercising young adults.","authors":"Gulinu Maimaituxun, Tatsuro Amano, Glen P Kenny, Toby Mündel, Masanobu Kajiki, Kaname Tagawa, Akira Katagiri, Yoko Tanabe, Koichi Watanabe, Takeshi Nishiyasu, Narihiko Kondo, Naoto Fujii","doi":"10.1007/s00421-024-05448-9","DOIUrl":null,"url":null,"abstract":"<p><strong>Purpose: </strong>Sweat glands and cutaneous vessels possess growth hormone (GH) and insulin-like growth factor 1 (IGF-1) receptors. Here, we assessed if exercise increases GH and IGF-1 in skin interstitial fluid, and whether baseline and exercise-induced increases in GH and IGF-1 concentrations in skin interstitial fluid/blood are associated with heat loss responses of sweating and cutaneous vasodilation.</p><p><strong>Methods: </strong>Sixteen young adults (7 women) performed a 50-min moderate-intensity exercise bout (50% VO<sub>2peak</sub>) during which skin dialysate and blood samples were collected. In a sub-study (n = 7, 4 women), we administered varying concentrations of GH (0.025-4000 ng/mL) and IGF-1 (0.000256-100 µg/mL) into skin interstitial fluid via intradermal microdialysis. Sweat rate (ventilated capsule) and cutaneous vascular conductance (CVC) were measured continuously for both studies.</p><p><strong>Results: </strong>Exercise increased sweating and CVC (both P < 0.001), paralleled by increases of serum GH and skin dialysate GH and IGF-1 (all P ≤ 0.041) without changes in serum IGF-1. Sweating was positively correlated with baseline dialysate and serum GH levels, as well as exercise-induced increases in serum GH and IGF-1 (all P ≤ 0.044). Increases in CVC were not correlated with any GH and IGF-1 variables. Exogenous administration of GH and IGF-1 did not modulate resting sweat rate and CVC.</p><p><strong>Conclusion: </strong>(1) Exercise increases GH and IGF-1 levels in the skin interstitial fluid, (2) exercise-induced sweating is associated with baseline GH in skin interstitial fluid and blood, as well as exercise-induced increases in blood GH and IGF-1, and (3) cutaneous vasodilation during exercise is not associated with GH and IGF-1 in skin interstitial fluid and blood.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":null,"pages":null},"PeriodicalIF":2.8000,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"European Journal of Applied Physiology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1007/s00421-024-05448-9","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/3/6 0:00:00","PubModel":"Epub","JCR":"Q2","JCRName":"PHYSIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Purpose: Sweat glands and cutaneous vessels possess growth hormone (GH) and insulin-like growth factor 1 (IGF-1) receptors. Here, we assessed if exercise increases GH and IGF-1 in skin interstitial fluid, and whether baseline and exercise-induced increases in GH and IGF-1 concentrations in skin interstitial fluid/blood are associated with heat loss responses of sweating and cutaneous vasodilation.
Methods: Sixteen young adults (7 women) performed a 50-min moderate-intensity exercise bout (50% VO2peak) during which skin dialysate and blood samples were collected. In a sub-study (n = 7, 4 women), we administered varying concentrations of GH (0.025-4000 ng/mL) and IGF-1 (0.000256-100 µg/mL) into skin interstitial fluid via intradermal microdialysis. Sweat rate (ventilated capsule) and cutaneous vascular conductance (CVC) were measured continuously for both studies.
Results: Exercise increased sweating and CVC (both P < 0.001), paralleled by increases of serum GH and skin dialysate GH and IGF-1 (all P ≤ 0.041) without changes in serum IGF-1. Sweating was positively correlated with baseline dialysate and serum GH levels, as well as exercise-induced increases in serum GH and IGF-1 (all P ≤ 0.044). Increases in CVC were not correlated with any GH and IGF-1 variables. Exogenous administration of GH and IGF-1 did not modulate resting sweat rate and CVC.
Conclusion: (1) Exercise increases GH and IGF-1 levels in the skin interstitial fluid, (2) exercise-induced sweating is associated with baseline GH in skin interstitial fluid and blood, as well as exercise-induced increases in blood GH and IGF-1, and (3) cutaneous vasodilation during exercise is not associated with GH and IGF-1 in skin interstitial fluid and blood.
期刊介绍:
The European Journal of Applied Physiology (EJAP) aims to promote mechanistic advances in human integrative and translational physiology. Physiology is viewed broadly, having overlapping context with related disciplines such as biomechanics, biochemistry, endocrinology, ergonomics, immunology, motor control, and nutrition. EJAP welcomes studies dealing with physical exercise, training and performance. Studies addressing physiological mechanisms are preferred over descriptive studies. Papers dealing with animal models or pathophysiological conditions are not excluded from consideration, but must be clearly relevant to human physiology.