Substrate utilization in the brain and skeletal muscle during environmental and energetic stress in humans
department or school: Health and Social Development, Faculty of (Okanagan)
department or school: Health and Exercise Sciences, School of (Okanagan)
data provider: DSpace
degree campus: UBCO
creator: Caldwell, Hannah Grace
issued: 2023-08-10T22:56:59Z
issued: 2023
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: Metabolism describes the sum of biochemical reactions that take place within a living organism which provide energy for vital processes; this can be studied at the whole-body, organ specific, or cellular level. Energy availability, which is determined by the difference between energy intake and exercise energy expenditure, is affected by environmental and energetic stresses (e.g., high-altitude, exercise, diet/nutrition). Systemic energy deficits have implications for the regulation of organ-specific substrate utilization and function. The aim of this thesis was to integrate brain, skeletal muscle, and systemic substrate oxidation and relative fuel utilization in the context of selected environmental and energetic stress (high-altitude, exercise, nutritional caloric deficits). Study 1 addressed a fundamental question for integrative cerebrovascular physiology: How are the cerebral metabolic rates of oxygen and glucose utilization (CMRO₂ and CMRGlu, respectively) affected by alterations in arterial PCO₂ (PaCO₂)? The results of this study indicate that cerebral oxidative metabolism (i.e., CMRO₂) is altered by approximately 1 % per mmHg change in PaCO₂. These changes, in part, are explained by an increased compensatory contribution of anaerobic metabolic pathways. Study 2 investigated the research question: How does systemic fuel utilization at high-altitude affect the brain inflammatory response to exercise? The results of this study provide new evidence that 6-8 days of acclimatization at 3,800 m does not provoke immune suppression or exacerbate systemic pro-inflammatory responses at rest or with maximal exercise. Further, altitude-induced alterations in systemic inflammatory responses did not directly affect release of pro-inflammatory cytokines by the brain with maximal exercise. Study 3A showed that 14-days low energy availability (LEA) – involving effectively 50% daily caloric restriction – in endurance-trained females provokes immunological stress, systemic infl…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/85441
note: SUBSTRATE UTILIZATION IN THE BRAIN AND SKELETAL MUSCLE DURING ENVIRONMENTAL AND ENERGETIC STRESS IN HUMANS by Hannah Grace Caldwell BHK., University of British Columbia, 2017 M.Sc., University of British Columbia, 2019 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE COLLEGE OF GRADUATE STUDIES (Kinesiology) THE UNIVERSITY OF BRITISH COLUMBIA (Okanagan) July 2023 © Hannah Grace Caldwell, 2023 ii The following individuals certify that they have read, and recommend to the College of Graduate Studies for acceptance, a thesis/dissertation entitled: SUBSTRATE UTILIZATION IN THE BRAIN AND SKELETAL MUSCLE DURING ENVIRONMENTAL AND ENERGETIC STRESS IN HUMANS submitted by Hannah Grace Caldwell in partial fulfillment of the requirements of the degree of Doctor of Philosophy in Kinesiology. Dr. Philip Ainslie, School of Health and Exercise Sciences Supervisor Dr. Jonathan Little, School of Health and Exercise Sciences Supervisory Committee Member Dr. Lasse Gliemann, University of Copenhagen Supervisory Committee Member Dr. Ylva Hellsten, University of Copenhagen Supervisory Committee Member Dr. Sarah Purcell, UBC Faculty of Medicine, Division of Endocrinology and Metabolism University Examiner Dr. José González-Alonso, Brunel University London External Examiner iii Abstract Metabolism describes the sum of biochemical reactions that take place within a living organism which provide energy for vital processes; this can be studied at the whole-body, organ specific, or cellular level. Energy availability, which is determined by the difference between energy intake and exercise energy expenditure, is affected by environmental and energetic stresses (e.g., high-altitude, exercise, diet/nutrition). Systemic energy deficits have implications for the regulation of organ-specific substrate utilization and function. The aim of this thesis was to integrate brain, skeletal muscle, and systemic substrate oxidation and relative fuel u…
has type: Thesis/Dissertation
date issued: 2023-09
is shown at: 10.14288/1.0435173
language: eng
degree discipline: Kinesiology
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
contributor: Ainslie, Philip N., 1974-
type: Text
identifier URI: http://hdl.handle.net/2429/85441