1
|
Stray-Gundersen S, Wojan F, Tanaka H, Lalande S. Similar endothelium-dependent vascular responses to intermittent hypoxia in young and older adults. J Appl Physiol (1985) 2024; 137:254-261. [PMID: 38932685 DOI: 10.1152/japplphysiol.00823.2023] [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: 11/17/2023] [Revised: 06/04/2024] [Accepted: 06/24/2024] [Indexed: 06/28/2024] Open
Abstract
Aging is associated with vascular endothelial dysfunction observed through a progressive loss of flow-mediated dilation caused partly by a decreased nitric oxide bioavailability. Intermittent hypoxia, consisting of alternating short bouts of breathing hypoxic and normoxic air, was reported to either maintain or improve vascular function in young adults. The aim of this study was to determine the impact of age on the vascular response to intermittent hypoxia. Twelve young adults and 11 older adults visited the laboratory on two occasions. Plasma nitrate concentrations and brachial artery flow-mediated dilation were assessed before and after exposure to either intermittent hypoxia or a sham protocol. Intermittent hypoxia consisted of eight 4-min hypoxic cycles at a targeted oxygen saturation of 80% interspersed with breathing room air to resaturation, and the sham protocol consisted of eight 4-min normoxic cycles interspersed with breathing room air. Vascular responses were assessed during intermittent hypoxia and the sham protocol. Intermittent hypoxia elicited a brachial artery vasodilation but did not change brachial artery shear rate in both young and older adults. Plasma nitrate concentrations were not significantly affected by intermittent hypoxia compared with the sham protocol in both groups. Brachial artery flow-mediated dilation was not acutely affected by intermittent hypoxia or the sham protocol in either young or older adults. In conclusion, the brachial artery vasodilatory response to intermittent hypoxia was not influenced by age. Intermittent hypoxia increased brachial artery diameter but did not acutely affect endothelium-dependent vasodilation in young or older adults.NEW & NOTEWORTHY The objective of this study was to determine the impact of age on the vascular response to intermittent hypoxia. Eight 4-min bouts of hypoxia at a targeted oxygen saturation of 80% induced a brachial artery vasodilation in both young and older adults, indicating that age does not influence the vasodilatory response to intermittent hypoxia. Intermittent hypoxia did not acutely affect brachial artery flow-mediated dilation in young or older adults.
Collapse
Affiliation(s)
- Sten Stray-Gundersen
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, Texas, United States
| | - Frank Wojan
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, Texas, United States
| | - Hirofumi Tanaka
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, Texas, United States
| | - Sophie Lalande
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, Texas, United States
| |
Collapse
|
2
|
Wojan F, Stray-Gundersen S, Zhao J, Lalande S. Impaired erythropoietin response to hypoxia in type 2 diabetes. Acta Diabetol 2024; 61:925-932. [PMID: 38570345 DOI: 10.1007/s00592-024-02269-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 03/03/2024] [Indexed: 04/05/2024]
Abstract
AIMS Patients with type 2 diabetes have a 20% lower total blood volume than age- and weight-matched healthy adults, suggesting a reduced capacity to transport oxygen in this population. Intermittent hypoxia, consisting of alternating short bouts of breathing hypoxic and normoxic air, increases erythropoietin levels, the hormone regulating red blood cell production, in young and older adults. The objective of this study was to determine the effect of a single session of intermittent hypoxia on erythropoietin levels and hemoglobin mass, the absolute mass of hemoglobin contained in red blood cells, in patients with type 2 diabetes. METHODS Ten patients with type 2 diabetes were exposed to an intermittent hypoxia protocol consisting of eight 4-min cycles at a targeted oxygen saturation of 80% interspersed with normoxic cycles to resaturation. Erythropoietin and hemoglobin mass responses to intermittent hypoxia in patients with type 2 diabetes were compared to previously published data from an identical intermittent hypoxia protocol performed in age-matched older adults. RESULTS Intermittent hypoxia increased erythropoietin levels in older adults but did not induce any change in erythropoietin levels in patients with type 2 diabetes (3.2 ± 2.2 vs. 0.2 ± 2.7 mU/ml, p = 0.01). Hemoglobin mass indexed to body weight was 21% lower in patients with type 2 diabetes than in older adults (8.1 ± 1.7 vs. 10.2 ± 2.1 g/kg, p < 0.01). CONCLUSIONS These findings suggest an impaired erythropoietin response to decreased oxygen levels in patients with type 2 diabetes, which may contribute to the reduced oxygen transport capacity observed in this population.
Collapse
Affiliation(s)
- Frank Wojan
- Department of Kinesiology and Heath Education, The University of Texas at Austin, Austin, TX, USA
| | - Sten Stray-Gundersen
- Department of Kinesiology and Heath Education, The University of Texas at Austin, Austin, TX, USA
| | - Jiahui Zhao
- Department of Kinesiology and Heath Education, The University of Texas at Austin, Austin, TX, USA
| | - Sophie Lalande
- Department of Kinesiology and Heath Education, The University of Texas at Austin, Austin, TX, USA.
| |
Collapse
|
3
|
Tregub PP, Komleva YK, Kulikov VP, Chekulaev PA, Tregub OF, Maltseva LD, Manasova ZS, Popova IA, Andriutsa NS, Samburova NV, Salmina AB, Litvitskiy PF. Relationship between Hypoxia and Hypercapnia Tolerance and Life Expectancy. Int J Mol Sci 2024; 25:6512. [PMID: 38928217 PMCID: PMC11204369 DOI: 10.3390/ijms25126512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Revised: 06/05/2024] [Accepted: 06/08/2024] [Indexed: 06/28/2024] Open
Abstract
The review discusses the potential relationship between hypoxia resistance and longevity, the influence of carbon dioxide on the mechanisms of aging of the mammalian organism, and intermittent hypercapnic-hypoxic effects on the signaling pathways of aging mechanisms. In the article, we focused on the potential mechanisms of the gero-protective efficacy of carbon dioxide when combined with hypoxia. The review summarizes the possible influence of intermittent hypoxia and hypercapnia on aging processes in the nervous system. We considered the perspective variants of the application of hypercapnic-hypoxic influences for achieving active longevity and the prospects for the possibilities of developing hypercapnic-hypoxic training methods.
Collapse
Affiliation(s)
- Pavel P. Tregub
- Department of Pathophysiology, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
- Brain Science Institute, Research Center of Neurology, 125367 Moscow, Russia; (Y.K.K.)
- Scientific and Educational Resource Center “Innovative Technologies of Immunophenotyping, Digital Spatial Profiling and Ultrastructural Analysis”, RUDN University, 117198 Moscow, Russia
| | - Yulia K. Komleva
- Brain Science Institute, Research Center of Neurology, 125367 Moscow, Russia; (Y.K.K.)
| | - Vladimir P. Kulikov
- Department of Ultrasound and Functional Diagnostics, Altay State Medical University, 656040 Barnaul, Russia
| | - Pavel A. Chekulaev
- Department of Pathophysiology, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | | | - Larisa D. Maltseva
- Department of Pathophysiology, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | - Zaripat Sh. Manasova
- Department of Pathophysiology, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | - Inga A. Popova
- Department of Pathophysiology, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | - Natalia S. Andriutsa
- Department of Pathophysiology, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | - Natalia V. Samburova
- Department of Pathophysiology, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | - Alla B. Salmina
- Brain Science Institute, Research Center of Neurology, 125367 Moscow, Russia; (Y.K.K.)
| | - Peter F. Litvitskiy
- Department of Pathophysiology, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| |
Collapse
|
4
|
Sakamoto R, Kamoda T, Sato K, Ogoh S, Katayose M, Neki T, Iwamoto E. Acute aerobic exercise enhances cerebrovascular shear-mediated dilation in young adults: the role of cerebral shear. J Appl Physiol (1985) 2024; 136:535-548. [PMID: 38153849 DOI: 10.1152/japplphysiol.00543.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 12/22/2023] [Accepted: 12/22/2023] [Indexed: 12/30/2023] Open
Abstract
Exercise-induced increases in shear rate (SR) acutely improve peripheral endothelial function, but the presence of this mechanism in cerebral arteries remains unclear. Thus, we evaluated shear-mediated dilation of the internal carotid artery (ICA), which is an index of cerebrovascular endothelial function, before and after exercise. Shear-mediated dilation was measured with 30 s of hypercapnia in 16 young adults before and 10 min after 30 min of sitting rest (CON) or three cycling exercises on four separate days. The target exercise intensity was 80% of oxygen uptake at the ventilatory threshold. To manipulate the ICA SR during exercise, participants breathed spontaneously (ExSB, SR increase) or hyperventilated without (ExHV, no increase in SR) or with ([Formula: see text], restoration of SR increase) addition of CO2 to inspiratory air. Shear-mediated dilation was calculated as a percent increase in diameter from baseline. Doppler ultrasound measures ICA velocity and diameter. The CON trial revealed that 30 min of sitting did not alter shear-mediated dilation (4.34 ± 1.37% to 3.44 ± 1.23%, P = 0.052). ICA dilation after exercise compared with preexercise levels increased in the ExSB trial (3.32 ± 1.37% to 4.74 ± 1.84%, P < 0.01), remained unchanged in the ExHV trial (4.07 ± 1.55% to 3.21 ± 1.48%, P = 0.07), but was elevated in the [Formula: see text] trial (3.35 ± 1.15% to 4.33 ± 2.12%, P = 0.04). Our results indicate that exercise-induced increases in cerebral shear may play a crucial role in improving cerebrovascular endothelial function after acute exercise in young adults.NEW & NOTEWORTHY We found that 30-min cycling (target intensity was 80% of the ventilatory threshold) with increasing shear of the internal carotid artery (ICA) enhanced transient hypercapnia-induced shear-mediated dilation of the ICA, reflecting improved cerebrovascular endothelial function. This enhancement of ICA dilation was diminished by suppressing the exercise-induced increase in ICA shear via hyperventilation. Our results indicate that increases in cerebral shear may be a key stimulus for improving cerebrovascular endothelial function after exercise in young adults.
Collapse
Affiliation(s)
- Rintaro Sakamoto
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
- Japan Society for the Promotion of Science, Tokyo, Japan
| | - Tatsuki Kamoda
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Kohei Sato
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Shigehiko Ogoh
- Department of Biomedical Engineering, Toyo University, Kawagoe, Japan
| | - Masaki Katayose
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
- School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Toru Neki
- School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Erika Iwamoto
- School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| |
Collapse
|
5
|
Saito S, Watanabe H, Iwamoto E, Ogoh S. Handgrip exercise does not alter CO 2 -mediated cerebrovascular flow-mediated dilation. Exp Physiol 2023; 108:1337-1346. [PMID: 37626473 PMCID: PMC10988491 DOI: 10.1113/ep091125] [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: 01/05/2023] [Accepted: 07/24/2023] [Indexed: 08/27/2023]
Abstract
Handgrip exercise (HG), a small muscle exercise, improves cognitive function and is expected to provide a useful exercise mode to maintain cerebral health. However, the effect of HG on cerebral blood flow regulation is not fully understood. The present study aimed to examine the effect of acute HG on cerebral endothelial function as one of the essential cerebral blood flow regulatory functions. Thirteen healthy young participants performed interval HG, consisting of 4 sets of 2 min HG at 25% of maximum voluntary contraction with 3 min recovery between each set. Cognitive performance was evaluated before and at 5 and 60 min after interval HG using the Go/No-Go task (reaction time and accuracy). The diameter and blood velocity of the internal carotid artery (ICA) were measured using a duplex Doppler ultrasound system. To assess cerebral endothelial function, hypercapnia (30 s of hypercapnia stimulation, end-tidal partial pressure of CO2 : +9 mmHg)-induced cerebrovascular flow-mediated dilatation (cFMD) was induced, calculated as relative peak dilatation from baseline diameter. The shear rate (SR) was calculated using the diameter and blood velocity of the ICA. As a result, cognitive performance improved only at 5 min after interval HG (reaction time, P = 0.008; accuracy, P = 0.186), whereas ICA SR during interval HG and cFMD after interval HG were unchanged (P = 0.313 and P = 0.440, respectively). These results suggest that enhancement in cerebral endothelial function is not an essential mechanism responsible for acute HG-induced cognitive improvement. NEW FINDINGS: What is the central question of this study? Does handgrip exercise, a small muscle exercise, improve cerebral endothelial function? What is the main finding and its importance? Acute interval isometric handgrip exercise (2 min of exercise at 25% maximum voluntary contraction, followed by 3 min of recovery, repeated for a total of 4 sets) did not improve cerebral endothelial function. Since the cerebrovascular shear rate did not change during exercise, it is possible that acute handgrip exercise is not sufficient stimulation to improve cerebral endothelial function.
Collapse
Affiliation(s)
- Shotaro Saito
- Department of Biomedical EngineeringToyo UniversityKawagoeJapan
| | | | - Erika Iwamoto
- School of Health ScienceSapporo Medical UniversitySapporoJapan
| | - Shigehiko Ogoh
- Department of Biomedical EngineeringToyo UniversityKawagoeJapan
- Neurovascular Research LaboratoryUniversity of South WalesPontypriddUK
| |
Collapse
|
6
|
Hanson BE, Casey DP. Intermittent versus continuous handgrip exercise and peripheral endothelial function: impact of shear rate fluctuations. J Appl Physiol (1985) 2023; 135:892-901. [PMID: 37650140 DOI: 10.1152/japplphysiol.00362.2023] [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: 06/07/2023] [Revised: 08/08/2023] [Accepted: 08/26/2023] [Indexed: 09/01/2023] Open
Abstract
Sustained exercise-induced elevations in shear rate (SR) have been well established as beneficial for improving endothelial function. However, the impact of intermittent fluctuations in SR is not understood. We investigated the effect of intermittent SR elevations compared with sustained elevations on peripheral endothelial function. Brachial artery flow-mediated dilation (FMD) was assessed in 13 adults (9 M/4 F; 22 ± 4 yr) before and after 30 min of handgrip exercise. Three different rhythmic forearm exercise interventions were performed at a rate of 20 contractions/min. Intermittent exercises (6 × 3 min exercise interspersed by 2 min of rest) were performed at 25% (INT-25%) and 15% (INT-15%) maximum voluntary contraction (MVC), and continuous exercise was completed at 15% MVC. Brachial artery diameter and velocity were measured using Doppler ultrasound. The total increase in SR above baseline throughout exercise was greater during INT-25% (4,441 ± 516 s-1) and continuous (4,070 ± 407 s-1) compared with INT-15% (2,811 ± 342 s-1, P < 0.05). The %FMD increased following all exercises (INT-25%: 5.7 ± 1.2% to 8.1 ± 1.2%; INT-15%: 5.2 ± 1.2% to 7.0 ± 1.1%; continuous: 5.5 ± 1.3% to 6.8 ± 1.3%, P < 0.05 for all). The increase following INT-25% was significantly greater than INT-15% and continuous (P < 0.05 for both). Normalized FMD to shear rate area under the curve increased with intermittent exercise (INT-25%: 2.2 ± 0.2% to 3.4 ± 0.3%; INT-15%: 2.1 ± 0.2% to 3.2 ± 0.2%, P < 0.05 for both) but did not following continuous (2.1 ± 0.2% to 2.5 ± 0.1%, P = 0.06). The increase in normalized FMD with intermittent exercises were greater than continuous (P < 0.05 for both). These findings suggest intermittent fluctuations in SR during handgrip exercise may be more beneficial than sustained elevations on improving peripheral endothelial function.NEW & NOTEWORTHY Exercise-induced increases in shear rate is a well-established stimulus for improving peripheral endothelial function. This study presents novel findings that intermittent elevations in shear rate may be more effective at acutely improving endothelial function compared with continuous elevations. Despite similar increases in total shear rate during handgrip exercise intermittent elevations produced a significantly greater increase in endothelial function when compared with continuous elevations potentially indicating intermittent elevations as a more effective stimulus for acute improvements.
Collapse
Affiliation(s)
- Brady E Hanson
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States
| | - Darren P Casey
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States
- Abboud Cardiovascular Research Center, University of Iowa, Iowa City, Iowa, United States
- Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa, United States
| |
Collapse
|
7
|
Bock JM, Greenlund IM, Somers VK, Baker SE. Sex Differences in Neurovascular Control: Implications for Obstructive Sleep Apnea. Int J Mol Sci 2023; 24:13094. [PMID: 37685900 PMCID: PMC10487948 DOI: 10.3390/ijms241713094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 08/10/2023] [Accepted: 08/14/2023] [Indexed: 09/10/2023] Open
Abstract
Patients with obstructive sleep apnea (OSA) have a heightened risk of developing cardiovascular diseases, namely hypertension. While seminal evidence indicates a causal role for sympathetic nerve activity in the hypertensive phenotype commonly observed in patients with OSA, no studies have investigated potential sex differences in the sympathetic regulation of blood pressure in this population. Supporting this exploration are large-scale observational data, as well as controlled interventional studies in healthy adults, indicating that sleep disruption increases blood pressure to a greater extent in females relative to males. Furthermore, females with severe OSA demonstrate a more pronounced hypoxic burden (i.e., disease severity) during rapid eye movement sleep when sympathetic nerve activity is greatest. These findings would suggest that females are at greater risk for the hemodynamic consequences of OSA and related sleep disruption. Accordingly, the purpose of this review is three-fold: (1) to review the literature linking sympathetic nerve activity to hypertension in OSA, (2) to highlight recent experimental data supporting the hypothesis of sex differences in the regulation of sympathetic nerve activity in OSA, and (3) to discuss the potential sex differences in peripheral adrenergic signaling that may contribute to, or offset, cardiovascular risk in patients with OSA.
Collapse
Affiliation(s)
- Joshua M. Bock
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN 55901, USA; (J.M.B.)
| | - Ian M. Greenlund
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN 55901, USA; (J.M.B.)
| | - Virend K. Somers
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN 55901, USA; (J.M.B.)
| | - Sarah E. Baker
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN 55901, USA
| |
Collapse
|
8
|
Jacob DW, Morgenthaler LD, Harper JL, Limberg JK. The forearm vascular response to sympathetic activation is attenuated in female, but not male, participants following acute intermittent hypoxia. J Appl Physiol (1985) 2023; 135:352-361. [PMID: 37410902 PMCID: PMC10396222 DOI: 10.1152/japplphysiol.00760.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 06/05/2023] [Accepted: 06/30/2023] [Indexed: 07/08/2023] Open
Abstract
Acute exposure to hypoxia promotes both an increase in sympathetic nervous system activity (SNA) and local vasodilation. In rodents, intermittent hypoxia (IH)-mediated increases in SNA are associated with an increase in blood pressure in males but not females; notably, the protective effect of female sex is lost following ovariectomy. These data suggest the vascular response to hypoxia and/or SNA following IH may be sex- and/or hormone specific-although mechanisms are unclear. We hypothesized that hypoxia-mediated vasodilation and SNA-mediated vasoconstriction would be unchanged following acute IH in male adults. We further hypothesized that hypoxic vasodilation would be augmented and SNA-mediated vasoconstriction would be attenuated in female adults following acute IH, with the greatest effect when endogenous estradiol was high. Twelve male (25 ± 1 yr) and 10 female (25 ± 1 yr) participants underwent 30 min of IH. Females were studied in a low (early follicular) and high (late follicular) estradiol state. Preceding and following IH, participants completed two trials [steady-state hypoxia and cold pressor test (CPT)], where forearm blood flow and blood pressure were measured and used to determine forearm vascular conductance (FVC). The FVC response to hypoxia (P = 0.67) and sympathetic activation (P = 0.73) were unchanged following IH in males. There was no effect of IH on hypoxic vasodilation in females, regardless of estradiol state (P = 0.75). In contrast, the vascular response to sympathetic activation was attenuated in females following IH (P = 0.02), independent of estradiol state (P = 0.65). Present data highlight sex-related differences in neurovascular responsiveness following acute IH.NEW & NOTEWORTHY We examined the effects of acute intermittent hypoxia (AIH) on the vascular response to sympathetic activation and acute hypoxia. Present findings show, despite no effect of AIH on the vascular response to hypoxia, the forearm vasoconstrictor response to acute sympathetic activation is attenuated in females following AIH, independent of estradiol state. These data provide mechanistic understanding of potential benefits of AIH, as well as the impact of biological sex.
Collapse
Affiliation(s)
- Dain W Jacob
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri, United States
| | - Leandra D Morgenthaler
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri, United States
| | - Jennifer L Harper
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri, United States
| | - Jacqueline K Limberg
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri, United States
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri, United States
| |
Collapse
|
9
|
Sakamoto R, Sato K, Ogoh S, Kamoda T, Neki T, Katayose M, Iwamoto E. Dynamic resistance exercise-induced pressor response does not alter hypercapnia-induced cerebral vasodilation in young adults. Eur J Appl Physiol 2023; 123:781-796. [PMID: 36454281 DOI: 10.1007/s00421-022-05096-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 11/12/2022] [Indexed: 12/05/2022]
Abstract
Excessive arterial pressure elevation induced by resistance exercise (RE) attenuates peripheral vasodilatory function, but its effect on cerebrovascular function is unknown. We aimed to evaluate the effect of different pressor responses to RE on hypercapnia-induced vasodilation of the internal carotid artery (ICA), an index of cerebrovascular function. To manipulate pressor responses to RE, 15 healthy young adults (11M/4F) performed two RE: high intensity with low repetitions (HL) and low intensity with high repetitions (LH) dynamic knee extension. ICA dilation, induced by 3 min of hypercapnia, was measured before and 10 min after RE using Doppler ultrasound. HL exercise elicited a greater pressor response than LH exercise. In relaxation phases of RE, ICA blood velocity increased in both HL and LH trials. However, ICA shear rate did not significantly increase in either trial (P = 0.06). Consequently, neither exercise altered post-exercise hypercapnia-induced ICA dilation (HL, 3.9 ± 1.9% to 5.1 ± 1.7%; LH, 4.6 ± 1.4% to 4.8 ± 1.8%; P > 0.05 for all). When viewed individually, the changes in ICA shear rate were positively correlated with changes in end-tidal partial pressure of carbon dioxide (PETCO2) (r = 0.46, P < 0.01) than with mean arterial pressure (r = 0.32, P = 0.02). These findings suggest that the effects of RE-induced pressor response on cerebrovascular function may be different from peripheral arteries. An increase in PETCO2 during the relaxation phase may play a more crucial role than elevated pressure in increasing cerebral shear during dynamic RE.
Collapse
Affiliation(s)
- Rintaro Sakamoto
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
- Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan
| | - Kohei Sato
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Shigehiko Ogoh
- Department of Biomedical Engineering, Toyo University, Kawagoe, Japan
| | - Tatsuki Kamoda
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Toru Neki
- Department of Physical Therapy, School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Masaki Katayose
- Department of Physical Therapy, School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Erika Iwamoto
- Department of Physical Therapy, School of Health Sciences, Sapporo Medical University, Sapporo, Japan.
| |
Collapse
|
10
|
Carr JMJR, Howe CA, Gibbons TD, Tymko MM, Steele AR, Vizcardo-Galindo GA, Tremblay JC, Ainslie PN. Cerebral endothelium-dependent function and reactivity to hypercapnia: the role of α 1-adrenoreceptors. J Appl Physiol (1985) 2022; 133:1356-1367. [PMID: 36326471 DOI: 10.1152/japplphysiol.00400.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
We assessed hypercapnic cerebrovascular reactivity (CVR) and endothelium-dependent function [cerebral shear-mediated dilation (cSMD)] in the internal carotid artery (ICA) with and without systemic α1-adrenoreceptor blockade via Prazosin. We hypothesized that CVR would be reduced, whereas cSMD would remain unchanged, after Prazosin administration when compared with placebo. In 15 healthy adults (3 female, 26 ± 4 years), we conducted ICA duplex ultrasound during CVR [target +10 mmHg partial pressure of end-tidal carbon dioxide ([Formula: see text]) above baseline, 5 min] and cSMD (+9 mmHg [Formula: see text] above baseline, 30 s) using dynamic end-tidal forcing with and without α1-adrenergic blockade (Prazosin; 0.05 mg/kg) in a placebo-controlled, double-blind, and randomized design. The CVR in the ICA was not different between placebo and Prazosin (P = 0.578). During CVR, the reactivities of mean arterial pressure and cerebrovascular conductance to hypercapnia were also not different between conditions (P = 0.921 and P = 0.664, respectively). During Prazosin, cSMD was lower (1.1 ± 2.0% vs 3.8 ± 3.0%; P = 0.032); however, these data should be interpreted with caution due to the elevated baseline diameter (+1.3 ± 3.6%; condition: P = 0.0498) and lower shear rate (-14.5 ± 23.0%; condition: P < 0.001). Therefore, lower cSMD post α1-adrenoreceptor blockade might not indicate a reduction in cerebral endothelial function per se, but rather, that α1-adrenoreceptors contribute to resting cerebral vascular restraint at the level of the ICA.NEW & NOTEWORTHY We assessed steady-state hypercapnic cerebrovascular reactivity and cerebral endothelium-dependent function, with and without α1-adrenergic blockade (Prazosin), in a placebo-controlled, double-blind, and randomized study, to assess the contribution of α1-adrenergic receptors to cerebrovascular CO2 regulation. After administration of Prazosin, cerebrovascular reactivity to CO2 was not different compared with placebo despite lower blood flow, whereas cerebral endothelium-dependent function was reduced, likely due to elevated baseline internal carotid arterial diameter. These findings suggest that α1-adrenoreceptor activity does not influence cerebral blood flow regulation to CO2 and cerebral endothelial function.
Collapse
Affiliation(s)
- Jay M J R Carr
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia - Okanagan Campus, Kelowna, British Columbia, Canada
| | - Connor A Howe
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia - Okanagan Campus, Kelowna, British Columbia, Canada
| | - Travis D Gibbons
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia - Okanagan Campus, Kelowna, British Columbia, Canada
| | - Michael M Tymko
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia - Okanagan Campus, Kelowna, British Columbia, Canada.,Faculty of Kinesiology, Sport, and Recreation, University of Alberta, Edmonton, Alberta, Canada.,Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Andrew R Steele
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia - Okanagan Campus, Kelowna, British Columbia, Canada
| | - Gustavo A Vizcardo-Galindo
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia - Okanagan Campus, Kelowna, British Columbia, Canada
| | - Joshua C Tremblay
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia - Okanagan Campus, Kelowna, British Columbia, Canada
| | - Philip N Ainslie
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia - Okanagan Campus, Kelowna, British Columbia, Canada
| |
Collapse
|
11
|
Yuan H, Liu J, Gu Y, Ji X, Nan G. Intermittent hypoxia conditioning as a potential prevention and treatment strategy for ischemic stroke: Current evidence and future directions. Front Neurosci 2022; 16:1067411. [PMID: 36507357 PMCID: PMC9732261 DOI: 10.3389/fnins.2022.1067411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 11/11/2022] [Indexed: 11/26/2022] Open
Abstract
Ischemic stroke (IS) is the leading cause of disability and death worldwide. Owing to the aging population and unhealthy lifestyles, the incidence of cerebrovascular disease is high. Vascular risk factors include hypertension, diabetes, dyslipidemia, and obesity. Therefore, in addition to timely and effective reperfusion therapy for IS, it is crucial to actively control these risk factors to reduce the incidence and recurrence rates of IS. Evidence from human and animal studies suggests that moderate intermittent hypoxia (IH) exposure is a promising therapeutic strategy to ameliorate common vascular risk factors and comorbidities. Given the complex pathophysiological mechanisms underlying IS, effective treatment must focus on reducing injury in the acute phase and promoting repair in the recovery phase. Therefore, this review discusses the preclinical perspectives on IH conditioning as a potential treatment for neurovascular injury and highlights IH pre and postconditioning strategies for IS. Hypoxia conditioning reduces brain injury by increasing resistance to acute ischemic and hypoxic stress, exerting neuroprotective effects, and promoting post-injury repair and regeneration. However, whether IH produces beneficial effects depends not only on the hypoxic regimen but also on inter-subject differences. Therefore, we discuss the factors that may influence the effectiveness of IH treatment, including age, sex, comorbidities, and circadian rhythm, which can be used to help identify the optimal intervention population and treatment protocols for more accurate, individualized clinical translation. In conclusion, IH conditioning as a non-invasive, non-pharmacological, systemic, and multi-targeted intervention can not only reduce brain damage after stroke but can also be applied to the prevention and functional recovery of IS, providing brain protection at different stages of the disease. It represents a promising therapeutic strategy. For patients with IS and high-risk groups, IH conditioning is expected to develop as an adjunctive clinical treatment option to reduce the incidence, recurrence, disability, and mortality of IS and to reduce disease burden.
Collapse
Affiliation(s)
- Honghua Yuan
- Department of Neurology, China-Japan Union Hospital of Jilin University, Changchun, China
| | - Jia Liu
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Beijing Advanced Innovation Center for Big Data-based Precision Medicine, Capital Medical University, Beijing, China
| | - Yuhang Gu
- Department of Neurology, China-Japan Union Hospital of Jilin University, Changchun, China
| | - Xunming Ji
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Beijing Advanced Innovation Center for Big Data-based Precision Medicine, Capital Medical University, Beijing, China,Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China,*Correspondence: Xunming Ji,
| | - Guangxian Nan
- Department of Neurology, China-Japan Union Hospital of Jilin University, Changchun, China,Guangxian Nan,
| |
Collapse
|
12
|
Ogoh S, Washio T, Stacey BS, Tsukamoto H, Iannetelli A, Owens TS, Calverley TA, Fall L, Marley CJ, Bailey DM. Effects of continuous hypoxia on flow-mediated dilation in the cerebral and systemic circulation: on the regulatory significance of shear rate phenotype. J Physiol Sci 2022; 72:16. [PMID: 35858836 DOI: 10.1186/s12576-022-00841-5] [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: 04/01/2022] [Accepted: 07/07/2022] [Indexed: 11/10/2022]
Abstract
Emergent evidence suggests that cyclic intermittent hypoxia increases cerebral arterial shear rate and endothelial function, whereas continuous exposure decreases anterior cerebral oxygen (O2) delivery. To examine to what extent continuous hypoxia impacts cerebral shear rate, cerebral endothelial function, and consequent cerebral O2 delivery (CDO2), eight healthy males were randomly assigned single-blind to 7 h passive exposure to both normoxia (21% O2) and hypoxia (12% O2). Blood flow in the brachial and internal carotid arteries were determined using Duplex ultrasound and included the combined assessment of systemic and cerebral endothelium-dependent flow-mediated dilatation. Systemic (brachial artery) flow-mediated dilatation was consistently lower during hypoxia (P = 0.013 vs. normoxia), whereas cerebral flow-mediated dilation remained preserved (P = 0.927 vs. normoxia) despite a reduction in internal carotid artery antegrade shear rate (P = 0.002 vs. normoxia) and CDO2 (P < 0.001 vs. normoxia). Collectively, these findings indicate that the reduction in CDO2 appears to be independent of cerebral endothelial function and contrasts with that observed during cyclic intermittent hypoxia, highlighting the regulatory importance of (hypoxia) dose duration and flow/shear rate phenotype.
Collapse
Affiliation(s)
- Shigehiko Ogoh
- Department of Biomedical Engineering, Toyo University, Kawagoe, Saitama, Japan.,Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, CF37 4AT, UK
| | - Takuro Washio
- Department of Biomedical Engineering, Toyo University, Kawagoe, Saitama, Japan.,Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan
| | - Benjamin S Stacey
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, CF37 4AT, UK
| | - Hayato Tsukamoto
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, CF37 4AT, UK.,Faculty of Sport and Health Science, Ritsumeikan University, Shiga, Japan
| | - Angelo Iannetelli
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, CF37 4AT, UK
| | - Thomas S Owens
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, CF37 4AT, UK
| | - Thomas A Calverley
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, CF37 4AT, UK
| | - Lewis Fall
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, CF37 4AT, UK
| | - Christopher J Marley
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, CF37 4AT, UK
| | - Damian M Bailey
- Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, CF37 4AT, UK. .,Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan.
| |
Collapse
|
13
|
Guan Y, Liu J, Gu Y, Ji X. Effects of Hypoxia on Cerebral Microvascular Angiogenesis: Benefits or Damages? Aging Dis 2022; 14:370-385. [PMID: 37008044 PMCID: PMC10017152 DOI: 10.14336/ad.2022.0902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 09/02/2022] [Indexed: 11/18/2022] Open
Abstract
Cerebrovascular microcirculation is essential for maintaining the physiological functions of the brain. The brain can be protected from stress injury by remodeling the microcirculation network. Angiogenesis is a type of cerebral vascular remodeling. It is an effective approach to improve the blood flow of the cerebral microcirculation, which is necessary for preventing and treating various neurological disorders. Hypoxia is one of the most important regulators of angiogenesis, affecting the sprouting, proliferation, and maturation stages of angiogenesis. Moreover, hypoxia negatively affects cerebral vascular tissue by impairing the structural and functional integrity of the blood-brain barrier and vascular-nerve decoupling. Therefore, hypoxia has a dual effect on blood vessels and is affected by confounding factors including oxygen concentration, hypoxia duration, and hypoxia frequency and extent. Establishing an optimal model that promotes cerebral microvasculogenesis without causing vascular injury is essential. In this review, we first elaborate on the effects of hypoxia on blood vessels from two different perspectives: (1) the promotion of angiogenesis and (2) cerebral microcirculation damage. We further discuss the factors influencing the dual role of hypoxia and emphasize the benefits of moderate hypoxic irritation and its potential application as an easy, safe, and effective treatment for multiple nervous system disorders.
Collapse
Affiliation(s)
- Yuying Guan
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Beijing Advanced Innovation Center for Big Data-based Precision Medicine, Capital Medical University, Beijing, China
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Jia Liu
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Beijing Advanced Innovation Center for Big Data-based Precision Medicine, Capital Medical University, Beijing, China
| | - Yakun Gu
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Beijing Advanced Innovation Center for Big Data-based Precision Medicine, Capital Medical University, Beijing, China
| | - Xunming Ji
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Beijing Advanced Innovation Center for Big Data-based Precision Medicine, Capital Medical University, Beijing, China
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Correspondence should be addressed to: Dr. Prof. Xunming Ji; Beijing Institute of Brain Disorders, Capital Medical University, 10 Xi Tou Tiao, You Anmen, Beijing 100069, China. E-mail: .
| |
Collapse
|
14
|
Burtscher J, Mallet RT, Burtscher M, Millet GP. Hypoxia and brain aging: Neurodegeneration or neuroprotection? Ageing Res Rev 2021; 68:101343. [PMID: 33862277 DOI: 10.1016/j.arr.2021.101343] [Citation(s) in RCA: 100] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 04/06/2021] [Accepted: 04/09/2021] [Indexed: 12/12/2022]
Abstract
The absolute reliance of the mammalian brain on oxygen to generate ATP renders it acutely vulnerable to hypoxia, whether at high altitude or in clinical settings of anemia or pulmonary disease. Hypoxia is pivotal to the pathogeneses of myriad neurological disorders, including Alzheimer's, Parkinson's and other age-related neurodegenerative diseases. Conversely, reduced environmental oxygen, e.g. sojourns or residing at high altitudes, may impart favorable effects on aging and mortality. Moreover, controlled hypoxia exposure may represent a treatment strategy for age-related neurological disorders. This review discusses evidence of hypoxia's beneficial vs. detrimental impacts on the aging brain and the molecular mechanisms that mediate these divergent effects. It draws upon an extensive literature search on the effects of hypoxia/altitude on brain aging, and detailed analysis of all identified studies directly comparing brain responses to hypoxia in young vs. aged humans or rodents. Special attention is directed toward the risks vs. benefits of hypoxia exposure to the elderly, and potential therapeutic applications of hypoxia for neurodegenerative diseases. Finally, important questions for future research are discussed.
Collapse
Affiliation(s)
- Johannes Burtscher
- Department of Biomedical Sciences, University of Lausanne, CH-1015, Lausanne, Switzerland; Institute of Sport Sciences, University of Lausanne, CH-1015, Lausanne, Switzerland.
| | - Robert T Mallet
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| | - Martin Burtscher
- Department of Sport Science, University of Innsbruck, Innsbruck, Austria
| | - Grégoire P Millet
- Institute of Sport Sciences, University of Lausanne, CH-1015, Lausanne, Switzerland
| |
Collapse
|
15
|
Carr J, Tremblay JC, Ives SJ, Lyall GK, Baldwin MM, Birch KM, Lee KD, Papadedes DW, King TJ, Gibbons TD, Thomas KN, Hanson BE, Bock JM, Casey DP, Ruediger SL, Bailey TG, Amin SB, Hansen AB, Lawley JS, Williams JS, Cheng JL, MacDonald MJ. Commentaries on Viewpoint: Differential impact of shear rate in the cerebral and systemic circulation: implications for endothelial function. J Appl Physiol (1985) 2021; 130:1155-1160. [PMID: 33877934 DOI: 10.1152/japplphysiol.00045.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Jay Carr
- Centre for Heart, Lung and Vascular Health, University of British Columbia–Okanagan Campus, School of Health and Exercise Sciences, Kelowna, British Columbia, Canada
| | - Joshua C. Tremblay
- Centre for Heart, Lung and Vascular Health, University of British Columbia–Okanagan Campus, School of Health and Exercise Sciences, Kelowna, British Columbia, Canada
| | - Stephen J. Ives
- Health and Human Physiological Sciences, Skidmore College, Saratoga Springs, New York
| | - Gemma K. Lyall
- School of Biomedical Sciences, Faculty of Biological Sciences and Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, United Kingdom
| | - Molly M. Baldwin
- School of Biomedical Sciences, Faculty of Biological Sciences and Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, United Kingdom
| | - Karen M. Birch
- School of Biomedical Sciences, Faculty of Biological Sciences and Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, United Kingdom
| | - Kaitlyn D. Lee
- Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | | | - Trevor J. King
- Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Travis D. Gibbons
- Department of Physical Education, Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand
| | - Kate N. Thomas
- Department of Surgical Sciences, University of Otago, Dunedin, New Zealand
| | - Brady E. Hanson
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Joshua M. Bock
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota
| | - Darren P. Casey
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Stefanie L. Ruediger
- Physiology and Ultrasound Laboratory in Science and Exercise, Centre of Research on Exercise, Physical Activity and Health, The University of Queensland, Queensland, Australia
| | - Tom G. Bailey
- Physiology and Ultrasound Laboratory in Science and Exercise, Centre of Research on Exercise, Physical Activity and Health, The University of Queensland, Queensland, Australia,School of Nursing, Midwifery and Social Work, The University of Queensland, Queensland, Australia
| | - Sachin B. Amin
- Institute for Sport Science, Division of Physiology, Innsbruck University, Innsbruck, Austria
| | - Alexander B. Hansen
- Institute for Sport Science, Division of Physiology, Innsbruck University, Innsbruck, Austria
| | - Justin S. Lawley
- Institute for Sport Science, Division of Physiology, Innsbruck University, Innsbruck, Austria
| | - Jennifer S. Williams
- Vascular Dynamics Lab, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Jem L. Cheng
- Vascular Dynamics Lab, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Maureen J. MacDonald
- Vascular Dynamics Lab, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| |
Collapse
|
16
|
Mallet RT, Burtscher J, Richalet JP, Millet GP, Burtscher M. Impact of High Altitude on Cardiovascular Health: Current Perspectives. Vasc Health Risk Manag 2021; 17:317-335. [PMID: 34135590 PMCID: PMC8197622 DOI: 10.2147/vhrm.s294121] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 05/12/2021] [Indexed: 12/12/2022] Open
Abstract
Globally, about 400 million people reside at terrestrial altitudes above 1500 m, and more than 100 million lowlanders visit mountainous areas above 2500 m annually. The interactions between the low barometric pressure and partial pressure of O2, climate, individual genetic, lifestyle and socio-economic factors, as well as adaptation and acclimatization processes at high elevations are extremely complex. It is challenging to decipher the effects of these myriad factors on the cardiovascular health in high altitude residents, and even more so in those ascending to high altitudes with or without preexisting diseases. This review aims to interpret epidemiological observations in high-altitude populations; present and discuss cardiovascular responses to acute and subacute high-altitude exposure in general and more specifically in people with preexisting cardiovascular diseases; the relations between cardiovascular pathologies and neurodegenerative diseases at altitude; the effects of high-altitude exercise; and the putative cardioprotective mechanisms of hypobaric hypoxia.
Collapse
Affiliation(s)
- Robert T Mallet
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Johannes Burtscher
- Department of Biomedical Sciences, University of Lausanne, Lausanne, CH-1015, Switzerland
- Institute of Sport Sciences, University of Lausanne, Lausanne, CH-1015, Switzerland
| | - Jean-Paul Richalet
- Laboratoire Hypoxie & Poumon, UMR Inserm U1272, Université Sorbonne Paris Nord 13, Bobigny Cedex, F-93017, France
| | - Gregoire P Millet
- Department of Biomedical Sciences, University of Lausanne, Lausanne, CH-1015, Switzerland
- Institute of Sport Sciences, University of Lausanne, Lausanne, CH-1015, Switzerland
| | - Martin Burtscher
- Department of Sport Science, University of Innsbruck, Innsbruck, A-6020, Austria
- Austrian Society for Alpine and High-Altitude Medicine, Mieming, Austria
| |
Collapse
|
17
|
Sakamoto R, Katayose M, Yamada Y, Neki T, Kamoda T, Tamai K, Yamazaki K, Iwamoto E. High-but not moderate-intensity exercise acutely attenuates hypercapnia-induced vasodilation of the internal carotid artery in young men. Eur J Appl Physiol 2021; 121:2471-2485. [PMID: 34028613 DOI: 10.1007/s00421-021-04721-5] [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: 09/18/2020] [Accepted: 05/15/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE Exercise-induced increases in shear rate (SR) across different exercise intensities may differentially affect hypercapnia-induced vasodilation of the internal carotid artery (ICA), a potential index of cerebrovascular function. We aimed to elucidate the effects of exercise intensity on ICA SR during exercise and post-exercise hypercapnia-induced vasodilation of the ICA in young men. METHODS Twelve healthy men completed 30 min of cycling at moderate [MIE; 65 ± 5% of age-predicted maximal heart rate (HRmax)] and high (HIE; 85 ± 5% HRmax) intensities. Hypercapnia-induced vasodilation was induced by 3 min of hypercapnia (target end-tidal partial pressure of CO2 + 10 mmHg) and was assessed at pre-exercise, 5 min and 60 min after exercise. Doppler ultrasound was used to measure ICA diameter and blood velocity during exercise and hypercapnia tests. RESULTS SR was not altered during either exercise (interaction and main effects of time; both P > 0.05). ICA conductance decreased during HIE from resting values (5.1 ± 1.3 to 3.2 ± 1.0 mL·min-1·mmHg-1; P < 0.01) but not during MIE (5.0 ± 1.3 to 4.0 ± 0.8 mL·min-1·mmHg-1; P = 0.11). Consequently, hypercapnia-induced vasodilation declined immediately after HIE (6.9 ± 1.7% to 4.0 ± 1.4%; P < 0.01), but not after MIE (7.2 ± 2.1% to 7.3 ± 1.8%; P > 0.05). Sixty minutes after exercise, hypercapnia-induced vasodilation returned to baseline values in both trials (MIE 8.0 ± 3.1%; HIE 6.4 ± 2.9%; both P > 0.05). CONCLUSION The present study showed blunted hypercapnia-induced vasodilation of the ICA immediately after high-intensity exercise, but not a moderate-intensity exercise in young men. Given that the acute response is partly linked to the adaptive response in the peripheral endothelial function, the effects of aerobic training on cerebrovascular health may vary depending on exercise intensity.
Collapse
Affiliation(s)
- Rintaro Sakamoto
- Department of Physical Therapy, Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Masaki Katayose
- School of Health Science, Sapporo Medical University, Sapporo, Japan
| | - Yutaka Yamada
- Department of Physical Therapy, Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Toru Neki
- School of Health Science, Sapporo Medical University, Sapporo, Japan
| | - Tatsuki Kamoda
- School of Health Science, Sapporo Medical University, Sapporo, Japan
| | - Katsuyuki Tamai
- School of Health Science, Sapporo Medical University, Sapporo, Japan
| | - Kotomi Yamazaki
- School of Health Science, Sapporo Medical University, Sapporo, Japan
| | - Erika Iwamoto
- School of Health Science, Sapporo Medical University, Sapporo, Japan.
| |
Collapse
|
18
|
Wojan F, Stray-Gundersen S, Nagel MJ, Lalande S. Short exposure to intermittent hypoxia increases erythropoietin levels in healthy individuals. J Appl Physiol (1985) 2021; 130:1955-1960. [PMID: 33955265 DOI: 10.1152/japplphysiol.00941.2020] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Few minutes of hypoxic exposure stabilizes hypoxia-inducible factor-1α, resulting in erythropoietin (EPO) gene transcription and production. The objective of this study was to identify the shortest intermittent hypoxia protocol necessary to increase serum EPO levels in healthy individuals. In a first experiment, spontaneous EPO changes under normoxia (NORM) and the EPO response to five 4-min cycles of intermittent hypoxia (IH5) were determined in six individuals. In a second experiment, the EPO response to eight 4-min cycles of intermittent hypoxia (IH8) and 120 min of continuous hypoxia (CONT) was determined in six individuals. All hypoxic protocols were performed at a targeted arterial oxygen saturation of 80%. There was no significant change in EPO levels in response to normoxia or in response to five cycles of intermittent hypoxia (NORM: 9.5 ± 1.8 to 10.5 ± 1.8, IH5: 11.4 ± 2.3 to 13.4 ± 2.1 mU/mL, main effect for time P = 0.35). There was an increase in EPO levels in response to eight cycles of intermittent hypoxia and 120 min of continuous hypoxia, with peak levels observed 4.5 h after the onset of hypoxia (IH8: 11.2 ± 2.0 to 16.7 ± 2.2, CONT: 11.1 ± 3.8 to 19.4 ± 3.8 mU/mL, main effect for time P < 0.01). Eight cycles of intermittent hypoxia increased EPO levels to a similar extent as 120 min of continuous hypoxia (main effect for condition P = 0.36). Eight 4-min cycles of intermittent hypoxia represent the shortest protocol to increase serum EPO levels in healthy individuals.NEW & NOTEWORTHY The objective of this study was to identify the shortest intermittent hypoxia protocol necessary to increase serum erythropoietin levels in healthy individuals. Eight 4-min bouts of intermittent hypoxia, representing a hypoxic duration of 32 min at an arterial oxygen saturation of 80%, significantly increased erythropoietin levels in healthy individuals. These findings suggest that a short session of intermittent hypoxia has the potential to increase oxygen-carrying capacity.
Collapse
Affiliation(s)
- Frank Wojan
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, Texas
| | - Sten Stray-Gundersen
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, Texas
| | - Mercedes J Nagel
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, Texas
| | - Sophie Lalande
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, Texas
| |
Collapse
|
19
|
Ogoh S, Bailey DM. Last Word on Viewpoint: Differential impact of shear rate in the cerebral and systemic circulation: implications for endothelial function. J Appl Physiol (1985) 2021; 130:1161-1162. [PMID: 33877935 DOI: 10.1152/japplphysiol.00059.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Shigehiko Ogoh
- Department of Biomedical Engineering, Toyo University, Kawagoe, Japan.,Neurovascular Research Laboratory, University of South Wales, Pontypridd, United Kingdom
| | - Damian M Bailey
- Neurovascular Research Laboratory, University of South Wales, Pontypridd, United Kingdom
| |
Collapse
|
20
|
Ogoh S, Bailey DM. Differential impact of shear rate in the cerebral and systemic circulation: implications for endothelial function. J Appl Physiol (1985) 2021; 130:1152-1154. [DOI: 10.1152/japplphysiol.00735.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Affiliation(s)
- Shigehiko Ogoh
- Department of Biomedical Engineering, Toyo University, Saitama, Japan
- Neurovascular Research Laboratory, University of South Wales, Pontypridd, United Kingdom
| | - Damian M. Bailey
- Neurovascular Research Laboratory, University of South Wales, Pontypridd, United Kingdom
| |
Collapse
|
21
|
Ogoh S, Washio T, Suzuki K, Iemitsu M, Hashimoto T, Iwamoto E, Bailey DM. Greater increase in internal carotid artery shear rate during aerobic interval compared to continuous exercise in healthy adult men. Physiol Rep 2021; 9:e14705. [PMID: 33463912 PMCID: PMC7814484 DOI: 10.14814/phy2.14705] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 12/07/2020] [Accepted: 12/07/2020] [Indexed: 12/26/2022] Open
Abstract
Interval exercise has been determined to be more effective than continuous exercise for achieving improvement in the cardiovascular function of individuals suffering from cardiovascular disease. However, whether interval exercise improves the cerebrovascular function remains unclear. As per our hypothesis, interval exercise induces a higher cerebrovascular shear rate (SR) than continuous exercise. In this study, 11 adult men randomly performed continuous exercise for 12 min or work-equivalent (57.6 kJ/exercise session) interval exercise of semi-recumbent cycling. The SR in the internal carotid artery (ICA) represents an index of the cerebrovascular SR, which was measured during both the exercises using Doppler ultrasonography. Both the aerobic exercise modes increased the ICA SR. Moreover, the average ICA SR of the interval exercise for the final 4 min of exercise or 2 min of recovery was significantly higher than that for continuous exercise (exercise, 351 ± 75 vs. 330 ± 61/s, p = .038; recovery, 327 ± 86 vs. 290 ± 56/s, p = .014). To our knowledge, this is the first study to show that aerobic interval exercise increased the ICA SR more than equivalent work volume of aerobic continuous exercise. Thus, aerobic interval exercise may be more effective at stimulating the cerebrovasculature, resulting in greater improvements in cerebrovascular function as compared to continuous aerobic exercise in healthy adult men. These findings provide some important information that would help enhance exercise therapy programs for patients with arteriosclerosis, especially in the cerebral circulation.
Collapse
Affiliation(s)
- Shigehiko Ogoh
- Department of Biomedical EngineeringToyo UniversityKawagoe‐ShiJapan
- Neurovascular Research LaboratoryUniversity of South WalesPontypriddUK
| | - Takuro Washio
- Department of Biomedical EngineeringToyo UniversityKawagoe‐ShiJapan
- Research Fellow of Japan Society for the Promotion of ScienceTokyoJapan
| | - Kazuya Suzuki
- Department of Biomedical EngineeringToyo UniversityKawagoe‐ShiJapan
| | - Motoyuki Iemitsu
- Faculty of Sport and Health ScienceRitsumeikan UniversityShigaJapan
| | | | - Erika Iwamoto
- School of Health SciencesSapporo Medical UniversitySapporoJapan
| | - Damian M. Bailey
- Neurovascular Research LaboratoryUniversity of South WalesPontypriddUK
| |
Collapse
|
22
|
Iwamoto E, Sakamoto R, Tsuchida W, Yamazaki K, Kamoda T, Neki T, Katayose M, Casey DP. Effects of menstrual cycle and menopause on internal carotid artery shear-mediated dilation in women. Am J Physiol Heart Circ Physiol 2020; 320:H679-H689. [PMID: 33306444 DOI: 10.1152/ajpheart.00810.2020] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
This study aimed to elucidate the effects of change in estrogen during the menstrual cycle and menopause on shear-mediated dilation of the internal carotid artery (ICA), a potential index of cerebrovascular endothelial function. Shear-mediated dilation of the ICA and serum estradiol were measured in 11 premenopausal (Pre-M, 21 ± 1 yr), 13 perimenopausal (Peri-M, 49 ± 2 yr), and 10 postmenopausal (Post-M, 65 ± 7 yr) women. Measurements were made twice within the Pre-M group at their early follicular (EF, lower estradiol) and late follicular (LF, higher estradiol) phases. Shear-mediated dilation was induced by 3 min of hypercapnia (target PETCO2 + 10 mmHg from individual baseline) and was calculated as the percent rise in peak diameter relative to baseline diameter. ICA diameter and blood velocity were simultaneously measured by Doppler ultrasound. In Pre-M, shear-mediated dilation was higher during the LF phase than during the EF phase (P < 0.01). Comparing all groups, shear-mediated dilation was reduced across the menopausal transition (P < 0.01), and Pre-M during the LF phase showed the highest value (8.9 ± 1.4%) compared with other groups (Pre-M in EF, 6.4 ± 1.1%; Peri-M, 5.5 ± 1.3%; Post-M, 5.2 ± 1.9%, P < 0.05 for all). Shear-mediated dilation was positively correlated with serum estradiol even after adjustment of age (P < 0.01, r = 0.55, age-adjusted; P = 0.02, r = 0.35). Collectively, these data indicate that controlling the menstrual cycle phase is necessary for the cross-sectional assessments of shear-mediated dilation of the ICA in premenopausal women. Moreover, current findings suggest that a decline in cerebrovascular endothelial function may be partly related to the reduced circulating estrogen levels in peri- and postmenopausal women.NEW & NOTEWORTHY The present study evaluated the effects of the menstrual cycle and menopause stages on the shear-mediated dilation of the ICA, a potential index of cerebrovascular endothelial function, in pre-, peri-, and postmenopausal women. Shear-mediated dilation of the ICA was increased from the low- to high-estradiol phases in naturally cycling premenopausal women and was reduced with advancing menopause stages. Furthermore, lower estradiol was associated with reduced shear-mediated dilation of the ICA, independent of age.
Collapse
Affiliation(s)
- Erika Iwamoto
- School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Rintaro Sakamoto
- School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Wakako Tsuchida
- Department of Life Science and Biotechnology, National Institute of Advanced Industrial Science and Technology (AIST), Kagawa, Japan
| | - Kotomi Yamazaki
- School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Tatsuki Kamoda
- School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Toru Neki
- School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Masaki Katayose
- School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Darren P Casey
- Department of Physical Therapy and Rehabilitation Science, Iowa City, Iowa.,Abboud Cardiovascular Research Center, Iowa City, Iowa.,Fraternal Order of Eagles Diabetes Research Center, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| |
Collapse
|
23
|
Effect of a Single Session of Intermittent Hypoxia on Erythropoietin and Oxygen-Carrying Capacity. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17197257. [PMID: 33020411 PMCID: PMC7579477 DOI: 10.3390/ijerph17197257] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 09/30/2020] [Accepted: 10/02/2020] [Indexed: 12/24/2022]
Abstract
Intermittent hypoxia, defined as alternating bouts of breathing hypoxic and normoxic air, has the potential to improve oxygen-carrying capacity through an erythropoietin-mediated increase in hemoglobin mass. The purpose of this study was to determine the effect of a single session of intermittent hypoxia on erythropoietin levels and hemoglobin mass in young healthy individuals. Nineteen participants were randomly assigned to an intermittent hypoxia group (Hyp, n = 10) or an intermittent normoxia group (Norm, n = 9). Intermittent hypoxia consisted of five 4-min hypoxic cycles at a targeted arterial oxygen saturation of 90% interspersed with 4-min normoxic cycles. Erythropoietin levels were measured before and two hours following completion of the protocol. Hemoglobin mass was assessed the day before and seven days after exposure to intermittent hypoxia or normoxia. As expected, the intermittent hypoxia group had a lower arterial oxygen saturation than the intermittent normoxia group during the intervention (Hyp: 89 ± 1 vs. Norm: 99 ± 1%, p < 0.01). Erythropoietin levels did not significantly increase following exposure to intermittent hypoxia (Hyp: 8.2 ± 4.5 to 9.0 ± 4.8, Norm: 8.9 ± 1.7 to 11.1 ± 2.1 mU·mL−1, p = 0.15). Hemoglobin mass did not change following exposure to intermittent hypoxia. This single session of intermittent hypoxia was not sufficient to elicit a significant rise in erythropoietin levels or hemoglobin mass in young healthy individuals.
Collapse
|
24
|
Carr JMJR, Hoiland RL, Caldwell HG, Coombs GB, Howe CA, Tremblay JC, Green DJ, Ainslie PN. Internal carotid and brachial artery shear‐dependent vasodilator function in young healthy humans. J Physiol 2020; 598:5333-5350. [DOI: 10.1113/jp280369] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 09/07/2020] [Indexed: 12/12/2022] Open
Affiliation(s)
- Jay M. J. R. Carr
- Centre for Heart Lung and Vascular Health School of Health and Exercise Sciences University of British Columbia – Okanagan Campus Kelowna British Columbia Canada
| | - Ryan L. Hoiland
- Centre for Heart Lung and Vascular Health School of Health and Exercise Sciences University of British Columbia – Okanagan Campus Kelowna British Columbia Canada
- Department of Anesthesiology Pharmacology and Therapeutics Vancouver General Hospital University of British Columbia Vancouver British Columbia Canada
| | - Hannah G. Caldwell
- Centre for Heart Lung and Vascular Health School of Health and Exercise Sciences University of British Columbia – Okanagan Campus Kelowna British Columbia Canada
| | - Geoff B. Coombs
- Centre for Heart Lung and Vascular Health School of Health and Exercise Sciences University of British Columbia – Okanagan Campus Kelowna British Columbia Canada
| | - Connor A. Howe
- Centre for Heart Lung and Vascular Health School of Health and Exercise Sciences University of British Columbia – Okanagan Campus Kelowna British Columbia Canada
| | - Joshua C. Tremblay
- Centre for Heart Lung and Vascular Health School of Health and Exercise Sciences University of British Columbia – Okanagan Campus Kelowna British Columbia Canada
| | - Daniel J. Green
- School of Human Sciences (Sport and Exercise Sciences) The University of Western Australia Crawley Western Australia Australia
| | - Philip N. Ainslie
- Centre for Heart Lung and Vascular Health School of Health and Exercise Sciences University of British Columbia – Okanagan Campus Kelowna British Columbia Canada
| |
Collapse
|
25
|
Affiliation(s)
- Jay M J R Carr
- Centre for Heart, Lung and Vascular Health, University of British Columbia-Okanagan Campus, School of Health and Exercise Sciences, Kelowna, British Columbia, Canada
| | - Philip N Ainslie
- Centre for Heart, Lung and Vascular Health, University of British Columbia-Okanagan Campus, School of Health and Exercise Sciences, Kelowna, British Columbia, Canada
| |
Collapse
|