Exploring the physiological and molecular responses to environmental cross-acclimation

探索环境交叉适应的生理和分子反应

• 批准号: RGPIN-2022-04751
• 负责人: LoganSprenger, Heather
• 金额: $ 2.11万
• 依托单位: University of Ontario Institute of Technology
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=757062
• 关键词: Exploring; physiological; molecular; responses; environmental

Intermittent hypoxia training (IHT) in normobaric hypoxia posits a potential solution to allow sea-level individuals the ability to acquire some of the physiological adaptations of altitude without the cost and logistics of relocation. Although IHT is not a recent phenomenon, its use demonstrates equivocal effects on performance in normoxia, with many remaining questions regarding the optimal frequency, intensity, and duration of IHT to prove effective; most recent work demonstrates that a greater hypoxic stimulus with higher intensity, more frequency, and longer durations of IHT sessions posit beneficial physiological effects. Additionally, there is a current gap in our understanding of sex-based differences in response to acute and chronic hypoxia, the underlying mechanisms of response and adaptation specifically related to red blood cell (RBC) function, and the effect hypoxia has on cross-tolerance to heat and vice versa. As well, there is very limited research investigating the effect of intermittent hypoxia exposure on adaptations and performance in Paralympic athletes with varying amounts of functional ability. In this proposal, I aim to bridge the gap between scientific understanding of acute and chronic responses to hypoxia, and acclimation solutions to optimize work capacity and performance outcomes in extreme environments. Furthermore, the long-term goal of my research program is to understand the sex-based physiological and molecular mechanisms of acute and chronic responses to exercise and environmental stress to create interventions that optimize work capacity and performance outcomes. The short-term objectives include: 1) experimentally investigate the sex-based differences and physiological and molecular responses to acute normobaric hypoxia exposure of varying ascents, 2) examine the efficacy, mechanisms, and sex-based differences of short-term hypoxia acclimation (STHA) and its impact on the response to heat stress, and 3) examine the sex-based mechanisms and performance impact of short-term heat acclimation and cross-tolerance to hypoxia. These objectives are inherently linked, but are not necessarily sequentially dependent, ensuring high feasibility and minimal disruption if unanticipated results or delays emerge. This innovative work will fill existing knowledge gaps and markedly advance our understanding of the sex-based physiological and molecular mechanisms of acute and chronic responses to exercise and environmental stress. This knowledge will have broad and significant impact on guiding best practice for use of hypoxia and heat interventions for preparation of athletes, both able-bodied and para-sport, and occupational workers for exposure to extreme environmental conditions.

常压低氧间歇低氧训练(IHT)提出了一种潜在的解决方案，使海平面上的人能够在不需要重新安置的费用和后勤费用的情况下获得一些对海拔的生理适应。尽管间歇性低氧不是最近才出现的现象，但它的使用对常氧下的表现的影响是模棱两可的，许多关于最佳频率、强度和持续时间的问题仍然被证明是有效的；最近的研究表明，更大的低氧刺激和更高的强度、更多的频率和更长的持续时间的间歇性低氧训练具有有益的生理效应。此外，目前我们对急性和慢性低氧反应的性别差异、与红细胞(RBC)功能相关的反应和适应的潜在机制以及低氧对高温交叉耐受的影响的理解存在差距。此外，研究间歇性低氧暴露对具有不同功能能力的残奥会运动员的适应和表现的影响的研究非常有限。在这项提议中，我的目标是弥合对急性和慢性缺氧反应的科学理解与适应解决方案之间的差距，以优化极端环境下的工作能力和表现结果。此外，我的研究计划的长期目标是了解运动和环境压力的急性和慢性反应的基于性别的生理和分子机制，以创造干预措施，优化工作能力和表现结果。短期目标包括：1)实验研究不同上升量的急性常压低氧暴露的性别差异及生理和分子反应；2)检测短期低氧习服(STHA)的有效性、机制和性别差异及其对热应激反应的影响；3)检测短期热习服和交叉耐受低氧的性别差异机制和对运动成绩的影响。这些目标内在地联系在一起，但不一定是顺序依赖的，确保了高度的可行性，并在出现意外结果或延误时将干扰降至最低。这项创新的工作将填补现有的知识空白，并显著促进我们对运动和环境压力的急性和慢性反应的性别生理和分子机制的理解。这方面的知识将对指导使用缺氧和高温干预措施的最佳做法产生广泛而重大的影响，使健全人和准运动者以及职业工人做好暴露在极端环境条件下的准备。