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European Journal of Applied Physiology Dec 2020Herein, the principles of homoeostasis are re-visited, but with an emphasis upon repeated homoeostatic disturbances that give rise to physiological adaptation. The... (Review)
Review
Herein, the principles of homoeostasis are re-visited, but with an emphasis upon repeated homoeostatic disturbances that give rise to physiological adaptation. The central focus is human heat adaptation, and how, for experimental purposes, one might standardise successive adaptation stimuli, and then evaluate and compare the resulting adaptations. To provide sufficient background for that discussion, the principles of physiological control and regulation have been reviewed. The case is presented that, since it is the regulated variables that drive both the effector organs and the processes of physiological adaptation, then it is those variables (e.g., body temperature) that should be used to set and standardise the adaptation stimuli. Alternatively, some have proposed that the same outcome can be achieved through standardising a controlled variable (e.g., heart rate), and so the merits of that proposition are evaluated. Indeed, it can be an effective approach, although some experimental pitfalls are described to highlight its limitations with regard to between-group (e.g., able-bodied versus spinal-injured participants) and between-treatment comparisons (e.g., hot-water versus hot-air adaptation stimuli). The concept of setting the adaptation stimulus relative to an anaerobic or lactate threshold is also critically evaluated. Finally, an appraisal is offered concerning the merits of three different strategies for using deep-body and mean body temperature changes for evaluating thermoeffector adaptations.
Topics: Adaptation, Physiological; Body Temperature Regulation; Homeostasis; Hot Temperature; Humans; Research Design; Thermotolerance
PubMed: 32926190
DOI: 10.1007/s00421-020-04489-0 -
PloS One 2019Impairments in cognitive function, mood, and sleep quality occur following ascent to high altitude. Low oxygen (hypoxia) and poor sleep quality are both linked to...
Impairments in cognitive function, mood, and sleep quality occur following ascent to high altitude. Low oxygen (hypoxia) and poor sleep quality are both linked to impaired cognitive performance, but their independent contributions at high altitude remain unknown. Adaptive servoventilation (ASV) improves sleep quality by stabilizing breathing and preventing central apneas without supplemental oxygen. We compared the efficacy of ASV and supplemental oxygen sleep treatments for improving daytime cognitive function and mood in high-altitude visitors (N = 18) during acclimatization to 3,800 m. Each night, subjects were randomly provided with ASV, supplemental oxygen (SpO2 > 95%), or no treatment. Each morning subjects completed a series of cognitive function tests and questionnaires to assess mood and multiple aspects of cognitive performance. We found that both ASV and supplemental oxygen (O2) improved daytime feelings of confusion (ASV: p < 0.01; O2: p < 0.05) and fatigue (ASV: p < 0.01; O2: p < 0.01) but did not improve other measures of cognitive performance at high altitude. However, performance improved on the trail making tests (TMT) A and B (p < 0.001), the balloon analog risk test (p < 0.0001), and the psychomotor vigilance test (p < 0.01) over the course of three days at altitude after controlling for effects of sleep treatments. Compared to sea level, subjects reported higher levels of confusion (p < 0.01) and performed worse on the TMT A (p < 0.05) and the emotion recognition test (p < 0.05) on nights when they received no treatment at high altitude. These results suggest that stabilizing breathing (ASV) or increasing oxygenation (supplemental oxygen) during sleep can reduce feelings of fatigue and confusion, but that daytime hypoxia may play a larger role in other cognitive impairments reported at high altitude. Furthermore, this study provides evidence that some aspects of cognition (executive control, risk inhibition, sustained attention) improve with acclimatization.
Topics: Acclimatization; Adult; Affect; Altitude; Cognition; Female; Humans; Interactive Ventilatory Support; Male; Oxygen; Polysomnography; Self Report; Sleep Apnea, Central; Treatment Outcome; Young Adult
PubMed: 31188839
DOI: 10.1371/journal.pone.0217089 -
Biological Reviews of the Cambridge... Apr 2022Elucidating the physiological mechanisms that underlie thermal stress and discovering how species differ in capacities for phenotypic acclimatization and evolutionary...
Elucidating the physiological mechanisms that underlie thermal stress and discovering how species differ in capacities for phenotypic acclimatization and evolutionary adaptation to this stress is critical for understanding current latitudinal and vertical distribution patterns of species and for predicting their future state in a warming world. Such mechanistic analyses require careful choice of study systems (species and temperature-sensitive traits) and design of laboratory experiments that reflect the complexities of in situ conditions. Here, we critically review a wide range of studies of intertidal molluscs that provide mechanistic accounts of thermal effects across all levels of biological organization - behavioural, organismal, organ level, cellular, molecular, and genomic - and show how temperature-sensitive traits govern distribution patterns and capacities for coping with thermal stress. Comparisons of congeners from different thermal habitats are especially effective means for identifying adaptive variation. We employ these mechanistic analyses to illustrate how species differ in the severity of threats posed by rising temperature. Counterintuitively, we show that some of the most heat-tolerant species may be most threatened by increases in temperatures because of their small thermal safety margins and minimal abilities to acclimatize to higher temperatures. We discuss recent molecular biological and genomic studies that provide critical foundations for understanding the types of evolutionary changes in protein structure, RNA secondary structure, genome content, and gene expression capacities that underlie adaptation to temperature. Duplication of stress-related genes, as found in heat-tolerant molluscs, may provide enhanced capacity for coping with higher temperatures. We propose that the anatomical, behavioural, physiological, and genomic diversity found among intertidal molluscs, which commonly are of critical importance and high abundance in these ecosystems, makes this group of animals a highly appropriate study system for addressing questions about the mechanistic determinants of current and future distribution patterns of intertidal organisms.
Topics: Acclimatization; Adaptation, Physiological; Animals; Climate Change; Ecosystem; Mollusca; Temperature
PubMed: 34713568
DOI: 10.1111/brv.12811 -
Nature Communications Apr 2023At the molecular level, the evolution of life is driven by the generation and diversification of adaptation mechanisms. A universal description of adaptation-capable...
At the molecular level, the evolution of life is driven by the generation and diversification of adaptation mechanisms. A universal description of adaptation-capable chemical reaction network (CRN) structures has remained elusive until now, since currently-known criteria for adaptation apply only to a tiny subset of possible CRNs. Here we identify the definitive structural requirements that characterize all adaptation-capable collections of interacting molecules, however large or complex. We show that these network structures implement a form of integral control in which multiple independent integrals can collaborate to confer the capacity for adaptation on specific molecules. Using an algebraic algorithm informed by these findings, we demonstrate the existence of embedded integrals in a variety of biologically important CRNs that have eluded previous methods, and for which adaptation has been observed experimentally. This definitive picture of biological adaptation at the level of intermolecular interactions represents a blueprint for adaptation-capable signaling networks across all domains of life, and for the design of synthetic biosystems.
Topics: Adaptation, Physiological; Acclimatization; Signal Transduction
PubMed: 37081018
DOI: 10.1038/s41467-023-38011-9 -
International Journal of Molecular... Nov 2022Iron is an indispensable element that participates as an essential cofactor in multiple biological processes. However, when present in excess, iron can engage in redox...
Iron is an indispensable element that participates as an essential cofactor in multiple biological processes. However, when present in excess, iron can engage in redox reactions that generate reactive oxygen species that damage cells at multiple levels. In this report, we characterized the response of budding yeast species from the genus to elevated environmental iron concentrations. We have observed that strains are more resistant to high-iron concentrations than non- species. Liquid growth assays showed that species evolutionarily closer to , such as , , , and , were more resistant to high-iron levels than the more distant species and . Remarkably, strains were especially iron sensitive. Growth assays in solid media suggested that and were more resistant to the oxidative stress caused by elevated iron concentrations. When comparing iron accumulation and sensitivity, different patterns were observed. As previously described for , and particular strains of and became more sensitive to iron while accumulating more intracellular iron levels. However, no remarkable changes in intracellular iron accumulation were observed for the remainder of species. These results indicate that different mechanisms of response to elevated iron concentrations exist in the different species of the genus .
Topics: Saccharomyces; Saccharomyces cerevisiae; Adaptation, Physiological; Acclimatization; Iron
PubMed: 36430442
DOI: 10.3390/ijms232213965 -
International Journal of Environmental... Mar 2021Multiple sectors-health and non-health-can determine the health and well-being of people and the condition of the socio-ecological environment on which it depends. At...
Multiple sectors-health and non-health-can determine the health and well-being of people and the condition of the socio-ecological environment on which it depends. At the climate and human health nexus, a systems-based understanding of climate change and health should inform all stages of the policy process from problem conceptualization to design, implementation, and evaluation. Such an understanding should guide countries, their partners, and donors to incorporate health in strategic climate actions based on how health is affected by, and plays a role in, the dynamic interactions across economic, environmental, and societal domains. A systems-based approach to sustainable development has been widely promoted but operationalizing it for project level and policy development and implementation has not been well articulated. Such an approach is especially valuable for informing how to address climate change and health together through policy actions which can achieve multiple, mutually reinforcing goals. This commentary article describes strategic steps including the complementary use of health impact assessment, quantification of health impacts, and linking climate and health actions to national and global policy processes to apply a systems-based approach for developing climate mitigation and adaptation actions with human health benefits.
Topics: Acclimatization; Climate Change; Health Impact Assessment; Humans; Sustainable Development
PubMed: 33804531
DOI: 10.3390/ijerph18052398 -
Biological Reviews of the Cambridge... Nov 2017Nest building is a taxonomically widespread and diverse trait that allows animals to alter local environments to create optimal conditions for offspring development.... (Review)
Review
Nest building is a taxonomically widespread and diverse trait that allows animals to alter local environments to create optimal conditions for offspring development. However, there is growing evidence that climate change is adversely affecting nest-building in animals directly, for example via sea-level rises that flood nests, reduced availability of building materials, and suboptimal sex allocation in species exhibiting temperature-dependent sex determination. Climate change is also affecting nesting species indirectly, via range shifts into suboptimal nesting areas, reduced quality of nest-building environments, and changes in interactions with nest predators and parasites. The ability of animals to adapt to sustained and rapid environmental change is crucial for the long-term persistence of many species. Many animals are known to be capable of adjusting nesting behaviour adaptively across environmental gradients and in line with seasonal changes, and this existing plasticity potentially facilitates adaptation to anthropogenic climate change. However, whilst alterations in nesting phenology, site selection and design may facilitate short-term adaptations, the ability of nest-building animals to adapt over longer timescales is likely to be influenced by the heritable basis of such behaviour. We urgently need to understand how the behaviour and ecology of nest-building in animals is affected by climate change, and particularly how altered patterns of nesting behaviour affect individual fitness and population persistence. We begin our review by summarising how predictable variation in environmental conditions influences nest-building animals, before highlighting the ecological threats facing nest-building animals experiencing anthropogenic climate change and examining the potential for changes in nest location and/or design to provide adaptive short- and long-term responses to changing environmental conditions. We end by identifying areas that we believe warrant the most urgent attention for further research.
Topics: Adaptation, Physiological; Animals; Climate Change; Ecosystem; Nesting Behavior; Vertebrates
PubMed: 27982504
DOI: 10.1111/brv.12317 -
Brazilian Journal of Biology = Revista... 2023Considering the cooperative sector capabilities in organizing rural people, primarily focusing on empowering manpower and adopting a sustainable approach to basic...
Considering the cooperative sector capabilities in organizing rural people, primarily focusing on empowering manpower and adopting a sustainable approach to basic resources (water and soil), village-cooperative initiative has emerged as a new concept by registering and forming 4565 new cooperatives in Iran's rural regions. The present research which was conducted in two qualitative and quantitative phases designed a new model by integrating the new village-cooperative approach along with the sustainable livelihood's framework theory. The study sample of the qualitative phase included 32 theorists of the village-cooperative initiative. To analyze the data, the grounded theory and three-step process of open coding, axial coding and selective coding were used using MAXqda18 software. Finally, a paradigm model was designed whose most important components included causal conditions (shocks and seasonal conditions), contextual conditions (trends and governmental support), intervening conditions (control and market development), central categories (sustainable livelihoods with a village- cooperative approach), strategies (coping and adaptation) and consequences (creating jobs, establishing cooperatives, supporting smart agriculture and strengthening social capital). The statistical quantitative phase population consisted of cooperatives members in the village-cooperative initiative (N=405), being selected through Cochran's formula with proportional sampling method summing up to198 people from 5 provinces. The data collection tool was a researcher-made questionnaire whose validity and reliability were confirmed. The Bayesian structural equation modeling was used to analyze the data. The results of the research quantitative phase showed that the variables of financial capital, physical capital, social capital, coping and adaptation strategies, human capital and natural capital were the most effective variables on village-cooperative initiative members' sustainable livelihoods, respectively. Finally, a hybrid model based on the qualitative and quantitative studies was designed and suggestions were made; for instance, the creation of suitable grounds for off-farm activities such as rural industries and ecotourism.
Topics: Humans; Bayes Theorem; Reproducibility of Results; Sustainable Development; Acclimatization; Agriculture
PubMed: 36856234
DOI: 10.1590/1519-6984.269509 -
Sports Medicine (Auckland, N.Z.) Jul 2023Heat adaptation regimes are used to prepare athletes for exercise in hot conditions to limit a decrement in exercise performance. However, the heat adaptation literature... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Heat adaptation regimes are used to prepare athletes for exercise in hot conditions to limit a decrement in exercise performance. However, the heat adaptation literature mostly focuses on males, and consequently, current heat adaptation guidelines may not be optimal for females when accounting for the biological and phenotypical differences between sexes.
OBJECTIVES
We aimed to examine: (1) the effects of heat adaptation on physiological adaptations in females; (2) the impact of heat adaptation on performance test outcomes in the heat; and (3) the impact of various moderators, including duration (minutes and/or days), total heat dose (°Cmin), exercise intensity (kcalmin), total energy expended (kcal), frequency of heat exposures and training status on the physiological adaptations in the heat.
METHODS
SPORTDiscus, MEDLINE Complete and Embase databases were searched to December 2022. Random-effects meta-analyses for resting and exercise core temperature, skin temperature, heart rate, sweat rate, plasma volume and performance tests in the heat were completed using Stata Statistical Software: Release 17. Sub-group meta-analyses were performed to explore the effect of duration, total heat dose, exercise intensity, total energy expended, frequency of heat exposure and training status on resting and exercise core temperature, skin temperature, heart rate and sweat rate. An explorative meta-regression was conducted to determine the effects of physiological adaptations on performance test outcomes in the heat following heat adaptation.
RESULTS
Thirty studies were included in the systematic review; 22 studies were meta-analysed. After heat adaptation, a reduction in resting core temperature (effect size [ES] = - 0.45; 95% confidence interval [CI] - 0.69, - 0.22; p < 0.001), exercise core temperature (ES = - 0.81; 95% CI - 1.01, - 0.60; p < 0.001), skin temperature (ES = - 0.64; 95% CI - 0.79, - 0.48; p < 0.001), heart rate (ES = - 0.60; 95% CI - 0.74, - 0.45; p < 0.001) and an increase in sweat rate (ES = 0.53; 95% CI 0.21, 0.85; p = 0.001) were identified in females. There was no change in plasma volume (ES = - 0.03; 95% CI - 0.31, 0.25; p = 0.835), whilst performance test outcomes were improved following heat adaptation (ES = 1.00; 95% CI 0.56, 1.45; p < 0.001). Across all moderators, physiological adaptations were more consistently observed following durations of 451-900 min and/or 8-14 days, exercise intensity ≥ 3.5 kcalmin, total energy expended ≥ 3038 kcal, consecutive (daily) frequency and total heat dose ≥ 23,000 °Cmin. The magnitude of change in performance test outcomes in the heat was associated with a reduction in heart rate following heat adaptation (standardised mean difference = - 10 beatsmin; 95% CI - 19, - 1; p = 0.031).
CONCLUSIONS
Heat adaptation regimes induce physiological adaptations beneficial to thermoregulation and performance test outcomes in the heat in females. Sport coaches and applied sport practitioners can utilise the framework developed in this review to design and implement heat adaptation strategies for females.
Topics: Male; Humans; Female; Hot Temperature; Thermotolerance; Adaptation, Physiological; Exercise; Body Temperature Regulation
PubMed: 37222863
DOI: 10.1007/s40279-023-01831-2 -
PloS One 2022Anthropogenic changes in the environment are increasingly threatening the sustainability of socioecological systems on a global scale. As stewards of the natural capital...
BACKGROUND
Anthropogenic changes in the environment are increasingly threatening the sustainability of socioecological systems on a global scale. As stewards of the natural capital of over a quarter of the world's surface area, Indigenous Peoples (IPs), are at the frontline of these changes. Indigenous socioecological systems (ISES) are particularly exposed and sensitive to exogenous changes because of the intimate bounds of IPs with nature. Traditional food systems (TFS) represent one of the most prominent components of ISES, providing not only diverse and nutritious food but also critical socioeconomic, cultural, and spiritual assets. However, a proper understanding of how future climate change may compromise TFS through alterations of related human-nature interactions is still lacking. Climate change resilience of indigenous socioecological systems (RISE) is a new joint international project that aims to fill this gap in knowledge.
METHODS AND DESIGN
RISE will use a comparative case study approach coupling on-site socioeconomic, nutritional, and ecological surveys of the target ISES of Sakha (Republic of Sakha, Russian Federation) and Karen (Kanchanaburi, Thailand) people with statistical models projecting future changes in the distribution and composition of traditional food species under contrasting climate change scenarios. The results presented as alternative narratives of future climate change impacts on TFS will be integrated into a risk assessment framework to explore potential vulnerabilities of ISES operating through altered TFS, and possible adaptation options through stakeholder consultation so that lessons learned can be applied in practice.
DISCUSSION
By undertaking a comprehensive analysis of the socioeconomic and nutritional contributions of TFS toward the sustainability of ISES and projecting future changes under alternative climate change scenarios, RISE is strategically designed to deliver novel and robust science that will contribute towards the integration of Indigenous issues within climate change and sustainable agendas while generating a forum for discussion among Indigenous communities and relevant stakeholders. Its goal is to promote positive co-management and regional development through sustainability and climate change adaptation.
Topics: Acclimatization; Climate Change; Humans; Indigenous Peoples; Russia; Thailand
PubMed: 35862396
DOI: 10.1371/journal.pone.0271792