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Gillard BT, Amor N, Iraizoz FA, Pauža AG, Campbell C, Greenwood MP, Alagaili AN, Murphy D. Mobilisation of jerboa kidney gene networks during dehydration and opportunistic rehydration. iScience 2023; 26:107574. [PMID: 37664605 PMCID: PMC10470305 DOI: 10.1016/j.isci.2023.107574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 06/30/2023] [Accepted: 08/04/2023] [Indexed: 09/05/2023] Open
Abstract
Desert animals have evolved systems that enable them to thrive under dry conditions. Focusing on the kidney, we have investigated the transcriptomic adaptations that enable a desert rodent, the Lesser Egyptian Jerboa (Jaculus jaculus), to withstand water deprivation and opportunistic rehydration. Analysis of the whole kidney transcriptome showed many differentially expressed genes in the Jerboa kidney, 6.4% of genes following dehydration and an even greater number (36.2%) following rehydration compared to control. Genes correlated with the rehydration condition included many ribosomal protein coding genes suggesting a concerted effort to accelerate protein synthesis when water is made available. We identify an increase in TGF-beta signaling antagonists in dehydration (e.g., GREM2). We also describe expression of multiple aquaporin and solute carrier transporters mapped to specific nephron segments. The desert adapted renal transcriptome presented here is a valuable resource to expand our understanding of osmoregulation beyond that derived from model organisms.
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Affiliation(s)
- Benjamin T. Gillard
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, Dorothy Hodgkin Building, University of Bristol, Bristol, England
| | - Nabil Amor
- LR18ES05, Laboratory of Biodiversity, Parasitology and Ecology of Aquatic Ecosystems, Department of Biology - Faculty of Sciences of Tunis, University of Tunis El Manar, Tunisia
| | - Fernando Alvira Iraizoz
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, Dorothy Hodgkin Building, University of Bristol, Bristol, England
| | - Audrys G. Pauža
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, Dorothy Hodgkin Building, University of Bristol, Bristol, England
| | - Colin Campbell
- Department of Engineering Mathematics, Ada Lovelace Building, University of Bristol, Bristol, England
| | - Michael P. Greenwood
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, Dorothy Hodgkin Building, University of Bristol, Bristol, England
| | | | - David Murphy
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, Dorothy Hodgkin Building, University of Bristol, Bristol, England
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Kuzmina IV, Ovchinnikova NV, Tolpygo SM. Serum Activity of Proteolytic Enzyme Trypsin in Rats under Conditions of Water and Food Deprivation. Bull Exp Biol Med 2023; 175:608-611. [PMID: 37861909 DOI: 10.1007/s10517-023-05910-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Indexed: 10/21/2023]
Abstract
Trypsin is mainly regarded as a digestive enzyme, but there is evidence that activation of protease-activated receptor-2 (PAR-2) leads to behavioral changes. There are no data on trypsin activity in the serum of animals under conditions of thirst and starvation in the available literature. In our experiments, water deprivation led to a significant (p⩽0.05) increase in trypsin activity in rats, and food deprivation led to its decrease in comparison with controls (free access to water and food). After deprived rats received water and food, a decrease in trypsin activity was observed in both experimental groups. Changes in trypsin activity under conditions of water or food deprivation and after satiation were accompanied by shifts in some biochemical parameters of the bloods. Under conditions of metabolic stress (starvation and thirst), opposite changes in trypsin activity seem to indicate its participation in the mechanisms of adequate restructuring of metabolism and maintenance of vital processes in the body.
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Affiliation(s)
- I V Kuzmina
- P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia.
| | - N V Ovchinnikova
- P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia
| | - S M Tolpygo
- P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia
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Elsamad G, Mecawi AS, Pauža AG, Gillard B, Paterson A, Duque VJ, Šarenac O, Žigon NJ, Greenwood M, Greenwood MP, Murphy D. Ageing restructures the transcriptome of the hypothalamic supraoptic nucleus and alters the response to dehydration. NPJ AGING 2023; 9:12. [PMID: 37264028 PMCID: PMC10234251 DOI: 10.1038/s41514-023-00108-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 05/04/2023] [Indexed: 06/03/2023]
Abstract
Ageing is associated with altered neuroendocrine function. In the context of the hypothalamic supraoptic nucleus, which makes the antidiuretic hormone vasopressin, ageing alters acute responses to hyperosmotic cues, rendering the elderly more susceptible to dehydration. Chronically, vasopressin has been associated with numerous diseases of old age, including type 2 diabetes and metabolic syndrome. Bulk RNAseq transcriptome analysis has been used to catalogue the polyadenylated supraoptic nucleus transcriptomes of adult (3 months) and aged (18 months) rats in basal euhydrated and stimulated dehydrated conditions. Gene ontology and Weighted Correlation Network Analysis revealed that ageing is associated with alterations in the expression of extracellular matrix genes. Interestingly, whilst the transcriptomic response to dehydration is overall blunted in aged animals compared to adults, there is a specific enrichment of differentially expressed genes related to neurodegenerative processes in the aged cohort, suggesting that dehydration itself may provoke degenerative consequences in aged rats.
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Affiliation(s)
- Ghadir Elsamad
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, Dorothy Hodgkin Building, University of Bristol, Bristol, England
| | - André Souza Mecawi
- Laboratory of Molecular Neuroendocrinology, Department of Biophysics, Paulista School of Medicine, Federal University of São Paulo, São Paulo, Brazil
| | - Audrys G Pauža
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, Dorothy Hodgkin Building, University of Bristol, Bristol, England
- Translational Cardio-Respiratory Research Group, Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Benjamin Gillard
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, Dorothy Hodgkin Building, University of Bristol, Bristol, England
| | - Alex Paterson
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, Dorothy Hodgkin Building, University of Bristol, Bristol, England
- Insilico Consulting Ltd., Wapping Wharf, Bristol, England
| | - Victor J Duque
- Laboratory of Molecular Neuroendocrinology, Department of Biophysics, Paulista School of Medicine, Federal University of São Paulo, São Paulo, Brazil
| | - Olivera Šarenac
- Institute of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
- Department of Safety Pharmacology, Abbvie, North Chicago, Illinois, USA
| | - Nina Japundžić Žigon
- Institute of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Mingkwan Greenwood
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, Dorothy Hodgkin Building, University of Bristol, Bristol, England
| | - Michael P Greenwood
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, Dorothy Hodgkin Building, University of Bristol, Bristol, England
| | - David Murphy
- Molecular Neuroendocrinology Research Group, Bristol Medical School: Translational Health Sciences, Dorothy Hodgkin Building, University of Bristol, Bristol, England.
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Alterations in Kidney Structures Caused by Age Vary According to Sex and Dehydration Condition. Int J Mol Sci 2022; 23:ijms232415672. [PMID: 36555312 PMCID: PMC9779677 DOI: 10.3390/ijms232415672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/25/2022] [Accepted: 12/01/2022] [Indexed: 12/14/2022] Open
Abstract
Aging is a complex biological process, resulting in gradual and progressive decline in structure and function in many organ systems. Our objective is to determine if structural changes produced by aging vary with sex in a stressful situation such as dehydration. The expression of Slc12a3 mRNA in the renal cortex, α-smooth muscle actin (α-SMA), and fibronectin was evaluated in male and female rats, aged 3 and 18 months, submitted and not submitted to water deprivation (WD) for 48 h, respectively. When comparing ages, 18-month-old males showed a lower expression of Slc12a3 mRNA than 3-month-old males, and control and WD 18-month-old male and female rats exhibited a higher expression of α-SMA than the respective 3-month-old rats. Fibronectin was higher in both control and WD 18-month-old males than the respective 3-month-old males. In females, only the control 18-month-old rats showed higher fibronectin than the control 3-month-old rats. When we compared sex, control and WD 3-month-old female rats had a lower expression of Slc12a3 mRNA than the respective males. The WD 18-month-old male rats presented a higher expression of fibronectin and α-SMA than the WD 18-month-old female rats. When we compared hydric conditions, the WD 18-month-old males displayed a lower relative expression of Slc12a3 mRNA and higher α-SMA expression than the control 18-month-old males. Aging, sex, and dehydration lead to alterations in kidney structure.
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Age and sex influence the response in lipid metabolism of dehydrated Wistar rats. Sci Rep 2022; 12:9164. [PMID: 35655069 PMCID: PMC9163080 DOI: 10.1038/s41598-022-11587-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 04/19/2022] [Indexed: 11/21/2022] Open
Abstract
Aging is associated a decrease in thirst sensation, which makes old people more susceptible to dehydration. Dehydration produces energy metabolism alterations. Our objective was to determinate the effect of water deprivation (WD) in the lipid metabolism of old male and female rats. Here we show that in the state of WD, aging and sex alters retroperitoneal white adipose tissue (R-WAT) weight of rats, WD old female rats had more lipolysis products than old male rats, a sexual dimorphism in the hormonal response related with metabolism of the adipose tissue of old rats during WD, the expression of P-para mRNA in R-WAT did not present any alteration in animals submitted to WD, the expression of Aqp7 mRNA in R-WAT is altered by WD, age, and sex. Also, WD stimulated an increase in the plasma concentration of oxytocin and the expression of mRNA of the oxytocin receptors in R-WAT.
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Zhou HL, Wei MH, Cui Y, Di DS, Song WJ, Zhang RY, Liu JA, Wang Q. Association Between Water Intake and Mortality Risk-Evidence From a National Prospective Study. Front Nutr 2022; 9:822119. [PMID: 35495952 PMCID: PMC9039539 DOI: 10.3389/fnut.2022.822119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 03/01/2022] [Indexed: 11/28/2022] Open
Abstract
Background Few studies have explored the association between water intake and mortality risk, and the findings were inconsistent. Objective This study aimed to explore the water intake–mortality association, utilizing the data from the National Health and Nutrition Examination Survey (NHANES) and the 2015 public-linked mortality files released by the National Center for Health Statistics. Methods We used the diet- and mortality-linked data of a total of 35,463 adults (17,234 men) aged ≥20 years in the NHANESs 1999–2014 to perform a prospective study. The multivariate-adjusted Cox proportional hazards model was used to explore the associations of the amount of water intake (expressed by total water, plain water, beverage, and food water) and water intake proportion (expressed by the percentage of each kind of water) with mortality risks due to all causes, malignant neoplasms/cancer, and heart disease. The restricted cubic spline plots were adopted to clarify the dose–response relationships among them. Results With a median of 88 months (interquartile range: 49–136 months) follow-up, a total of 4,915 all-cause deaths occurred, including 1,073 and 861 deaths from malignant neoplasms/cancer and heart disease, respectively. The amount of water intake in either type was negatively associated with all-cause mortality risk. Additionally, the negative linear dose–response relationships of water intake and all-cause mortality risk were found for all types of water except for food water, which followed a non-linear pattern. Similarly, compared to the lowest quartile (beverage water intake: <676 g/day; food water intake: <532 g/day), beverage and food water intakes in the range of 1,033–1,524 and 1,612–3,802 g/day were associated with decreased malignant neoplasms/cancer mortality risk. A U-shaped dose–response relationship was found for beverage water intake and malignant neoplasms/cancer mortality risk and a negative linear dose–response relationship was found for food water intake and malignant neoplasms/cancer mortality risk. Coffee and/or tea consumption was/were negatively associated with mortality risks due to all causes and malignant neoplasms/cancer. No significant associations of water intake proportion and mortality risks were found. Conclusion Our findings demonstrated that higher water intake is associated with lower mortality risks among the United States population.
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Affiliation(s)
- Hao-Long Zhou
- MOE Key Lab of Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Mu-Hong Wei
- MOE Key Lab of Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yuan Cui
- MOE Key Lab of Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Dong-Sheng Di
- MOE Key Lab of Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Wen-Jing Song
- MOE Key Lab of Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ru-Yi Zhang
- MOE Key Lab of Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jun-An Liu
- Department of Social Medicine and Health Management, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qi Wang
- MOE Key Lab of Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Nuñez P, Arguelles J, Perillan C. Sex-specific influence of maternal exposure to bisphenol A on sodium and fluid balance in response to dipsogenic challenges in rats. Appetite 2022; 176:106091. [DOI: 10.1016/j.appet.2022.106091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 05/06/2022] [Accepted: 05/18/2022] [Indexed: 11/30/2022]
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Mietlicki-Baase EG, Santollo J, Daniels D. Fluid intake, what's dopamine got to do with it? Physiol Behav 2021; 236:113418. [PMID: 33838203 DOI: 10.1016/j.physbeh.2021.113418] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 03/12/2021] [Accepted: 04/05/2021] [Indexed: 12/27/2022]
Abstract
Maintaining fluid balance is critical for life. The central components that control fluid intake are only partly understood. This contribution to the collection of papers highlighting work by members of the Society for the Study of Ingestive Behavior focuses on the role that dopamine has on fluid intake and describes the roles that various bioregulators can have on thirst and sodium appetite by influencing dopamine systems in the brain. The goal of the review is to highlight areas in need of more research and to propose a framework to guide that research. We hope that this framework will inspire researchers in the field to investigate these interesting questions in order to form a more complete understanding of how fluid intake is controlled.
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Affiliation(s)
- Elizabeth G Mietlicki-Baase
- Department of Exercise and Nutrition Sciences, University at Buffalo, State University of New York, Buffalo, NY 14214, United States; Center for Ingestive Behavior Research, University at Buffalo, State University of New York, Buffalo, NY 14260, United States
| | - Jessica Santollo
- Department of Biology, University of Kentucky, Lexington, KY 40506, United States
| | - Derek Daniels
- Center for Ingestive Behavior Research, University at Buffalo, State University of New York, Buffalo, NY 14260, United States; Department of Psychology, University at Buffalo, State University of New York, Buffalo, NY 14260, United States
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Santollo J, Edwards AA. How predictive is body weight on fluid intake in rats? It depends on sex. Physiol Behav 2020; 229:113262. [PMID: 33232737 DOI: 10.1016/j.physbeh.2020.113262] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 11/13/2020] [Accepted: 11/19/2020] [Indexed: 02/08/2023]
Abstract
The assumption that body weight is a predictor of fluid intake is often used as rationale for normalizing intake to body weight when examining sex differences in drinking behavior. Nonuniform application of this body weight correction likely contributes to discrepancies in the literature. We, however, previously demonstrated sex differences in the relationship between body weight and angiotensin II (AngII)-stimulated water intake. Only after a pharmacological dose of AngII did water intake correlate with body weight, and only in males. Here we investigated whether body weight correlated with fluid intake stimulated by additional dipsogenic agents in male and female rats. We found that intake stimulated by either water deprivation or furosemide correlated with body weight in male rats. We found no relationship between intake and body weight after water deprivation, furosemide treatment, or isoproterenol treatment in females, nor did we find a relationship between intake and body weight after hypertonic saline treatment in either males or females. Finally, we report that daily water intake correlated with body weight in females. This effect, however, is likely the result of a relationship between body weight and food intake because when food was absent or reduced, the correlation between body weight and intake disappeared. These results demonstrate that multiple factors need to be considered when determining the best way to compare fluid intake between males and females and provides insight to help explain the discrepancies in the literature regarding sex differences in fluid intake.
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Affiliation(s)
- Jessica Santollo
- Department of Biology, University of Kentucky, Lexington, KY 40506.
| | - Andrea A Edwards
- Department of Biology, University of Kentucky, Lexington, KY 40506
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Chapman CL, Johnson BD, Parker MD, Hostler D, Pryor RR, Schlader Z. Kidney physiology and pathophysiology during heat stress and the modification by exercise, dehydration, heat acclimation and aging. Temperature (Austin) 2020; 8:108-159. [PMID: 33997113 PMCID: PMC8098077 DOI: 10.1080/23328940.2020.1826841] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 09/17/2020] [Accepted: 09/17/2020] [Indexed: 02/06/2023] Open
Abstract
The kidneys' integrative responses to heat stress aid thermoregulation, cardiovascular control, and water and electrolyte regulation. Recent evidence suggests the kidneys are at increased risk of pathological events during heat stress, namely acute kidney injury (AKI), and that this risk is compounded by dehydration and exercise. This heat stress related AKI is believed to contribute to the epidemic of chronic kidney disease (CKD) occurring in occupational settings. It is estimated that AKI and CKD affect upwards of 45 million individuals in the global workforce. Water and electrolyte disturbances and AKI, both of which are representative of kidney-related pathology, are the two leading causes of hospitalizations during heat waves in older adults. Structural and physiological alterations in aging kidneys likely contribute to this increased risk. With this background, this comprehensive narrative review will provide the first aggregation of research into the integrative physiological response of the kidneys to heat stress. While the focus of this review is on the human kidneys, we will utilize both human and animal data to describe these responses to passive and exercise heat stress, and how they are altered with heat acclimation. Additionally, we will discuss recent studies that indicate an increased risk of AKI due to exercise in the heat. Lastly, we will introduce the emerging public health crisis of older adults during extreme heat events and how the aging kidneys may be more susceptible to injury during heat stress.
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Affiliation(s)
- Christopher L. Chapman
- Center for Research and Education in Special Environments, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, USA
- Department of Human Physiology, University of Oregon, Eugene, OR, USA
| | - Blair D. Johnson
- Department of Kinesiology, School of Public Health, Indiana University, Bloomington, IN, USA
| | - Mark D. Parker
- Department of Physiology and Biophysics, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
- Department of Ophthalmology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - David Hostler
- Center for Research and Education in Special Environments, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, USA
| | - Riana R. Pryor
- Center for Research and Education in Special Environments, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, USA
| | - Zachary Schlader
- Department of Kinesiology, School of Public Health, Indiana University, Bloomington, IN, USA
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Watso JC, Robinson AT, Babcock MC, Migdal KU, Witman MAH, Wenner MM, Stocker SD, Farquhar WB. Short-term water deprivation attenuates the exercise pressor reflex in older female adults. Physiol Rep 2020; 8:e14581. [PMID: 32965797 PMCID: PMC7510566 DOI: 10.14814/phy2.14581] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/24/2020] [Accepted: 08/28/2020] [Indexed: 12/28/2022] Open
Abstract
Older adults have reduced fluid intake and impaired body fluid and electrolyte regulation. Older female adults exhibit exaggerated exercise blood pressure (BP) responses, which is associated with an increased risk of adverse cardiovascular events. However, it is unclear if dysregulated body fluid homeostasis contributes to altered exercise BP responses in older female adults. We tested the hypothesis that short-term water deprivation (WD) increases exercise BP responses in older female adults. Fifteen female adults (eight young [25 ± 6 years] and seven older [65 ± 6 years]) completed two experimental conditions in random crossover fashion; a euhydration control condition and a stepwise reduction in water intake over three days concluding with a 16-hr WD period. During both trials, beat-to-beat BP (photoplethysmography) and heart rate (electrocardiogram) were continuously assessed during rest, handgrip exercise (30% MVC), and post-exercise ischemia (metaboreflex isolation). At screening, older compared to young female adults had greater systolic and diastolic BP (p ≤ .02). Accelerometer-assessed habitual physical activity was not different between groups (p = .65). Following WD, 24-hr urine flow rate decreased, whereas thirst, urine specific gravity, and plasma osmolality increased (condition: p < .05 for all), but these WD-induced changes were not different between age groups (interaction: p ≥ .31 for all). Resting systolic and diastolic BP values were higher in older compared to young adults (p < .01 for both), but were not different between experimental conditions (p ≥ .20). In contrast to our hypothesis, WD was associated with attenuated systolic BP responses during handgrip exercise (post hoc: p < .01) and post-exercise ischemia (post hoc: p = .03) in older, but not young, female adults. These data suggest that reduced water intake-induced challenges to body fluid homeostasis do not contribute to exaggerated exercise BP responses in post-menopausal female adults.
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Affiliation(s)
- Joseph C. Watso
- Department of Kinesiology and Applied PhysiologyUniversity of DelawareNewarkDEUSA
| | - Austin T. Robinson
- Department of Kinesiology and Applied PhysiologyUniversity of DelawareNewarkDEUSA
- School of KinesiologyNeurovascular Physiology LaboratoryAuburn UniversityAuburnALUSA
| | - Matthew C. Babcock
- Department of Kinesiology and Applied PhysiologyUniversity of DelawareNewarkDEUSA
| | - Kamila U. Migdal
- Department of Kinesiology and Applied PhysiologyUniversity of DelawareNewarkDEUSA
| | - Melissa A. H. Witman
- Department of Kinesiology and Applied PhysiologyUniversity of DelawareNewarkDEUSA
| | - Megan M. Wenner
- Department of Kinesiology and Applied PhysiologyUniversity of DelawareNewarkDEUSA
| | - Sean D. Stocker
- Department of MedicineUniversity of PittsburghPittsburghPAUSA
| | - William B. Farquhar
- Department of Kinesiology and Applied PhysiologyUniversity of DelawareNewarkDEUSA
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