Goulet Nicholas, McCormick James J, King Kelli E, Notley Sean R, Goldfield Gary S, Fujii Naoto, Amano Tatsuro, Kenny Glen P
Human and Environmental Physiology Research Unit, School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, Ontario, Canada, Canada.
Behavioural and Metabolic Research Unit, School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, Ontario, Canada, Canada.
Temperature (Austin). 2023 Feb 23;10(4):454-464. doi: 10.1080/23328940.2023.2176107. eCollection 2023.
With global warming, workers are increasingly exposed to strenuous occupations in hot environments. Given age- and disease-associated declines in thermoregulatory function, older workers are at an elevated risk of developing heat-related injuries. Brain-derived neurotrophic factor (BDNF) is thought to confer neuroprotection during acute exercise, however, the influence of environmental heat on BDNF responses during prolonged work remains unclear. Therefore, we evaluated serum BDNF concentrations before and after 180 min of moderate-intensity treadmill walking (200 W/m2) and after 60 min of post-exercise recovery in temperate (wet-bulb globe temperature (WBGT) 16°C) and hot (WBGT 32°C) environments in 13 healthy young men (mean [SD; 22 [3] years), 12 healthy older men (59 [4] years), 10 men with hypertension (HTN) (60 [4] years), and 9 men with type 2 diabetes (T2D) (60 [5] years). In the temperate condition, all but one participant (1 HTN) completed the 180 min of exercise. While exercise tolerance in the heat was lower in older men with HTN (117 min [45]) and T2D (123 min [42]) compared to healthy older men (159 min [31]) (both p ≤ 0.049), similar end-exercise rectal temperatures (38.9°C [0.4]) were observed across groups, paralleled by similar elevations in serum BDNF across groups at end-exercise (+1106 pg/mL [203]) and end-recovery (+938 pg/mL [146]; all p ≤ 0.01) in the heat. No changes in serum BDNF were observed in the temperate condition. Our findings indicate similar BDNF responses in individuals with HTN or T2D compared to their healthy counterparts, despite exhibiting reduced tolerance to heat.
随着全球变暖，工人们越来越多地在炎热环境中从事高强度工作。鉴于与年龄和疾病相关的体温调节功能下降，老年工人患热相关损伤的风险更高。脑源性神经营养因子（BDNF）被认为在急性运动期间具有神经保护作用，然而，环境热量对长时间工作期间BDNF反应的影响仍不清楚。因此，我们评估了13名健康年轻男性（平均[标准差；22[3]岁]）、12名健康老年男性（59[4]岁）、10名高血压（HTN）男性（60[4]岁）和9名2型糖尿病（T2D）男性（60[5]岁）在温带（湿球黑球温度（WBGT）16°C）和炎热（WBGT 32°C）环境中进行180分钟中等强度跑步机行走（200 W/m2）前后以及运动后恢复60分钟后的血清BDNF浓度。在温带条件下，除一名参与者（1名HTN患者）外，所有参与者都完成了180分钟的运动。与健康老年男性（159分钟[31]）相比，患有HTN的老年男性（117分钟[45]）和T2D的老年男性（123分钟[42]）在炎热环境中的运动耐力较低（均p≤0.049），但各组运动结束时的直肠温度相似（38.9°C[0.4]），同时在炎热环境中运动结束时（+1106 pg/mL[203]）和恢复结束时（+938 pg/mL[146]；所有p≤0.01）各组血清BDNF的升高也相似。在温带条件下未观察到血清BDNF的变化。我们的研究结果表明，与健康同龄人相比，患有HTN或T2D的个体尽管对热的耐受性降低，但BDNF反应相似。
