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Leach OK, Strong K, Mack GW, Gifford JR. The vascular response to acute sauna heating is similar in young and middle-aged adults. J Appl Physiol (1985) 2024; 136:573-582. [PMID: 38271083 DOI: 10.1152/japplphysiol.00287.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 01/25/2024] [Indexed: 01/27/2024] Open
Abstract
Sauna has been linked to a reduction of cardiovascular disease risk and is a promising nonpharmacological treatment for populations at risk of cardiovascular disease. This study examined the vascular response to an acute bout of sauna heating in young and middle-aged individuals. Ten young (25 ± 4 yr, 6 males and 4 females) and eight middle-aged adults (56 ± 4 yr, 4 males and 4 females) underwent 40 min of sauna exposure at 80°C. Esophageal and intramuscular temperatures, brachial and superficial femoral artery blood flow, artery diameter, and shear rates were recorded at baseline and following heat exposure. Brachial artery flow-mediated dilation (FMD) was measured at baseline and following 90 min of recovery. Esophageal and muscle temperatures increased similarly in the young and middle-aged adults by 1.5 ± 0.53 and 1.95 ± 0.70°C, respectively (P < 0.05). The shear rate increased by 170-200% (P < 0.001), while blood flow increased by 180-390% (P < 0.001) in the superficial femoral and brachial arteries, respectively, and did not differ between age groups (P = 0.190-0.899). Systolic blood pressure was reduced from 135 ± 17 to 122 ± 20 mmHg (P = 0.017) in middle-aged participants. These data indicate that young and middle-aged adults have similar vascular responses to acute sauna heating.NEW & NOTEWORTHY Sauna therapy has been shown to improve cardiovascular health and function in older adults and individuals with cardiovascular disease risk factors. Specifically, improvements in vascular function have been reported and have been attributed to the increased hemodynamic stimuli on the vasculature associated with thermal stress. The present study quantified this hemodynamic response to a sauna protocol associated with improved cardiovascular health across the lifespan. Our data show that middle-aged adults have the same shear rate and blood flow response to sauna as young adults.
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Affiliation(s)
- Olivia K Leach
- Department of Exercise Sciences, Brigham Young University, Provo, Utah, United States
| | - Kaitlyn Strong
- Department of Exercise Sciences, Brigham Young University, Provo, Utah, United States
| | - Gary W Mack
- Department of Exercise Sciences, Brigham Young University, Provo, Utah, United States
| | - Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, Utah, United States
- Program of Gerontology, Brigham Young University, Provo, Utah, United States
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Gifford JR, Blackmon C, Hales K, Hinkle LJ, Richards S. Overdot and overline annotation must be understood to accurately interpret V.O 2MAX physiology with the Fick formula. Front Physiol 2024; 15:1359119. [PMID: 38444762 PMCID: PMC10912163 DOI: 10.3389/fphys.2024.1359119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 01/26/2024] [Indexed: 03/07/2024] Open
Abstract
Few formulas have been used in exercise physiology as extensively as the Fick formula, which calculates the rate of oxygen consumption (i.e., V.O2) as the product of cardiac output (Q.) and the difference in oxygen content in arterial and mixed venous blood (Δav ¯ O2). Unfortunately, the physiology of maximum V.O2 (V.O2MAX) is often misinterpreted due to a lack of appreciation for the limitations represented by the oft-ignored superscript annotations in the Fick formula. The purpose of this perspective is to explain the meaning of the superscript annotations and highlight how such annotations influence proper interpretation of V.O2MAX physiology with the Fick formula. First, we explain the significance of the overdots above V.O2 and Q., which indicate a measure per unit of time. As we will show, the presence of an overdot above Q. and lack of one above Δav ¯ O2 denotes they are different types of ratios and should be interpreted in the context of one another-not in contrast to each other as is commonplace. Second, we discuss the significance of the overline above the "v ¯ " in Δav ¯ O2, which indicates the venous sample is an average of blood that comes from mixed sources. The mixed nature of the venous sample has major implications for interpreting the influence of oxygen diffusion and blood flow heterogeneity on V.O2MAX. Ultimately, we give recommendations and insights for using the Fick formula to calculate V.O2 and interpret V.O2MAX physiology.
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Affiliation(s)
- Jayson R. Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
- Program of Gerontology, Brigham Young University, Provo, UT, United States
| | - Christina Blackmon
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
| | - Katelynn Hales
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
| | - Lee J. Hinkle
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
| | - Shay Richards
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
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Dorff A, Bradford C, Hunsaker A, Atkinson J, Rhees J, Leach OK, Gifford JR. Vascular dysfunction and the age-related decline in critical power. Exp Physiol 2024; 109:240-254. [PMID: 37934136 PMCID: PMC10988715 DOI: 10.1113/ep091571] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 10/18/2023] [Indexed: 11/08/2023]
Abstract
Ageing results in lower exercise tolerance, manifested as decreased critical power (CP). We examined whether the age-related decrease in CP occurs independently of changes in muscle mass and whether it is related to impaired vascular function. Ten older (63.1 ± 2.5 years) and 10 younger (24.4 ± 4.0 years) physically active volunteers participated. Physical activity was measured with accelerometry. Leg muscle mass was quantified with dual X-ray absorptiometry. The CP and maximum power during a graded exercise test (PGXT ) of single-leg knee-extension exercise were determined over the course of four visits. During a fifth visit, vascular function of the leg was assessed with passive leg movement (PLM) hyperaemia and leg blood flow and vascular conductance during knee-extension exercise at 10 W, 20 W, slightly below CP (90% CP) and PGXT . Despite not differing in leg lean mass (P = 0.901) and physical activity (e.g., steps per day, P = 0.735), older subjects had ∼30% lower mass-specific CP (old = 3.20 ± 0.94 W kg-1 vs. young = 4.60 ± 0.87 W kg-1 ; P < 0.001). The PLM-induced hyperaemia and leg blood flow and/or conductance were blunted in the old at 20 W, 90% CP and PGXT (P < 0.05). When normalized for leg muscle mass, CP was strongly correlated with PLM-induced hyperaemia (R2 = 0.52; P < 0.001) and vascular conductance during knee-extension exercise at 20 W (R2 = 0.34; P = 0.014) and 90% CP (R2 = 0.39; P = 0.004). In conclusion, the age-related decline in CP is not only an issue of muscle quantity, but also of impaired muscle quality that corresponds to impaired vascular function.
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Affiliation(s)
- Abigail Dorff
- Department of Exercise SciencesBrigham Young UniversityProvoUtahUSA
- Program of GerontologyBrigham Young UniversityProvoUtahUSA
| | - Christy Bradford
- Department of Exercise SciencesBrigham Young UniversityProvoUtahUSA
| | - Ashley Hunsaker
- Department of Exercise SciencesBrigham Young UniversityProvoUtahUSA
| | - Jake Atkinson
- Department of Exercise SciencesBrigham Young UniversityProvoUtahUSA
| | - Joshua Rhees
- Department of Exercise SciencesBrigham Young UniversityProvoUtahUSA
| | - Olivia K. Leach
- Department of Exercise SciencesBrigham Young UniversityProvoUtahUSA
- Program of GerontologyBrigham Young UniversityProvoUtahUSA
| | - Jayson R. Gifford
- Department of Exercise SciencesBrigham Young UniversityProvoUtahUSA
- Program of GerontologyBrigham Young UniversityProvoUtahUSA
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Hyldahl RD, Gifford JR, Davidson LE, Hancock CR, Hafen PS, Parcell AC, Mack GW. Physiological assessment of a 16 day, 4385 km ultra-endurance mountain bike race: A case study. Exp Physiol 2024; 109:165-174. [PMID: 38189630 PMCID: PMC10988653 DOI: 10.1113/ep091260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 10/23/2023] [Indexed: 01/09/2024]
Abstract
The Tour Divide (TD) is a 4385 km ultra-endurance bicycle race that follows the continental divide from Canada to Mexico. In this case study, we performed a comprehensive molecular and physiological profile before and after the completion of the TD. Assessments were performed 35 days before the start (Pre-TD) and ∼36 h after the finish (Post-TD). Total energy expenditure was assessed during the first 9 days by doubly labelled water (2 H2 18 O), abdominal and leg tissue volumes via MRI, and graded exercise tests to quantify fitness and substrate preference. Vastus lateralis muscle biopsies were taken to measure mitochondrial function via respirometry, and vascular function was assessed using Doppler ultrasound. The 47-year-old male subject took 16 days 7 h 45 min to complete the route. He rode an average of 16.8 h/day. Neither maximal O2 uptake nor maximal power output changed pre- to post-TD. Measurement of total energy expenditure and dietary recall records suggested maintenance of energy balance, which was supported by the lack of change in body weight. The subject lost both appendicular and trunk fat mass and gained leg lean mass pre- to post-TD. Skeletal muscle mitochondrial and vascular endothelial function decreased pre- to post-TD. Overall, exercise performance was maintained despite reductions in muscle mitochondrial and vascular endothelial function post-TD, suggesting a metabolic reserve in our highly trained athlete.
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Affiliation(s)
| | | | | | - Chad R. Hancock
- Department of Nutrition, Dietetics & Food ScienceBrigham Young UniversityProvoUtahUSA
| | - Paul S. Hafen
- Department of Exercise SciencesBrigham Young UniversityProvoUtahUSA
| | - Allen C. Parcell
- Department of Exercise SciencesBrigham Young UniversityProvoUtahUSA
| | - Gary W. Mack
- Department of Exercise SciencesBrigham Young UniversityProvoUtahUSA
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Leach OK, Gifford JR, Mack GW. Rapid onset vasodilation during baroreceptor loading and unloading. Am J Physiol Regul Integr Comp Physiol 2023; 325:R568-R575. [PMID: 37694334 DOI: 10.1152/ajpregu.00116.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 08/21/2023] [Accepted: 09/05/2023] [Indexed: 09/12/2023]
Abstract
The purpose of these experiments was to determine if the increase in vascular conductance following a single muscle contraction (50% of maximal voluntary contraction) (6 male and 6 female subjects) was altered during baroceptor loading and unloading. Rapid onset vasodilation (ROV) was determined by measuring brachial artery blood flow (Doppler ultrasound) and blood pressure (Finapress monitor). Brachial artery vascular conductance was calculated by dividing blood flow by mean arterial pressure. ROV was described by the area under the Δvascular conductance (VC)-time curve during the 30 s following muscle contraction. ROV was determined using chamber pressures of +20, +10, 0, -10, -20, and -40 mmHg (lower body positive and negative pressure, LBPP, and LBNP). We tested the hypothesis that the impact of baroreceptor loading and unloading produces a proportion change in ROV. The level of ROV following each contraction was proportional to the peak force (r2 = 0.393, P = 0.0001). Peak force was therefore used as a covariate in further analysis. ROV during application of -40 mmHg LBNP (0.345 ± 0.229 mL·mmHg-1) was lower than that observed at Control (0.532 ± 0.284 mL·mmHg-1, P = 0.034) and +20 mmHg LBPP (0.658 ± 0.364 mL·mmHg-1, P = 0.0008). ROV was linearly related to chamber pressure from -40 to +20 mmHg chamber pressure (r2 = 0.512, P = 0.022, n = 69) and from -20 to +10 mmHg chamber pressure (r2= 0.973, P < 0.0425, n = 45), Overall, vasoconstrictor tone altered with physiologically relevant baroreceptor loading and unloading resulted in a proportion change in ROV.NEW & NOTEWORTHY Rapid onset vasodilation (ROV) was linearly related to the peak force of each single 1-s muscle contraction. In addition, ROV is reduced by baroreceptor unloading (LBNP: -10, -120, and -40 mmHg) and increased by baroreceptor loading (LBPP: +10 and +20 mmHg). Without accounting for peak force and the level of baroreceptor engagement makes comparison of ROV in subjects of differing muscle size or strength untenable.
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Affiliation(s)
- Olivia K Leach
- Department of Exercise Sciences, Brigham Young University, Provo, Utah, United States
| | - Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, Utah, United States
| | - Gary W Mack
- Department of Exercise Sciences, Brigham Young University, Provo, Utah, United States
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Gifford JR, Larsen J. Our understanding of the role of exercise intensity can only be precise as our classification of exercise intensity. Exp Physiol 2023; 108:1374-1375. [PMID: 37750810 PMCID: PMC10988519 DOI: 10.1113/ep091512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 09/15/2023] [Indexed: 09/27/2023]
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James JJ, Leach OK, Young AM, Newman AN, Mpongo KL, Quirante JM, Wardell DB, Ahmadi M, Gifford JR. The exercise power-duration relationship is equally reproducible in eumenorrheic female and male humans. J Appl Physiol (1985) 2023; 134:230-241. [PMID: 36548510 DOI: 10.1152/japplphysiol.00416.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
This study aims to investigate the effect of the menstrual cycle (MC) on exercise performance across the power-duration relationship (PDR). We hypothesized females would exhibit greater variability in the PDR across the MC than males across a similar timespan, with critical power (CP) and work-prime (W') being lower during the early follicular phase than the late follicular and midluteal phases. Seven eumenorrheic, endurance-trained female adults performed multiple constant-load-to-task-failure and maximum-power tests at three timepoints across the MC (early follicular, late follicular, and midluteal phases). Ten endurance-trained male adults performed the same tests approximately 10 days apart. No differences across the PDR were observed between MC phases (CP: 186.74 ± 31.00 W, P = 0.955, CV = 0.81 ± 0.65%) (W': 7,961.81 ± 2,537.68 J, P = 0.476, CV = 10.48 ± 3.06%). CP was similar for male and female subjects (11.82 ± 1.42 W·kg-1 vs. 11.56 ± 1.51 W·kg-1, respectively) when controlling for leg lean mass. However, W' was larger (P = 0.047) for male subjects (617.28 ± 130.10 J·kg-1) than female subjects (490.03 ± 136.70 J·kg-1) when controlling for leg lean mass. MC phase does not need to be controlled when conducting aerobic endurance performance research on eumenorrheic female subjects without menstrual dysfunction. Nevertheless, several sex differences in the power-duration relationship exist, even after normalizing for body composition. Therefore, previous studies describing the physiology of exercise performance in male subjects may not perfectly describe that of female subjects.NEW & NOTEWORTHY Females are often excluded from exercise performance research due to experimental challenges in controlling for the menstrual cycle (MC), causing uncertainty regarding how the MC impacts female performance. The present study examined the influences that biological sex and the MC have on the power-duration relationship (PDR) by comparing critical power (CP), Work-prime (W'), and maximum power output (PMAX) in males and females. Our data provide evidence that the MC does not influence the PDR and that females exhibit similar reproducibility as males. Thus, when conducting aerobic endurance exercise research on eumenorrheic females without menstrual dysfunction, the phase of the MC does not need to be controlled. Although differences in body composition account for some differences between the sexes, sex differences in W' and PMAX persisted even after normalizing for different metrics of body composition. These data highlight the necessity and feasibility of examining sex differences in performance, as previously generated male-only data within the literature may not apply to female subjects.
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Affiliation(s)
- Jessica J James
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Olivia K Leach
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Arianna M Young
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Audrey N Newman
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Kiese L Mpongo
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Jaron M Quirante
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Devon B Wardell
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Mohadeseh Ahmadi
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, Utah.,Program of Gerontology, Brigham Young University, Provo, Utah
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Marchant ED, Nelson WB, Hyldahl RD, Gifford JR, Hancock CR. Passive heat stress induces mitochondrial adaptations in skeletal muscle. Int J Hyperthermia 2023; 40:2205066. [PMID: 37106474 DOI: 10.1080/02656736.2023.2205066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023] Open
Abstract
The mitochondria are central to skeletal muscle metabolic health. Impaired mitochondrial function is associated with various muscle pathologies, including insulin resistance and muscle atrophy. As a result, continuous efforts are made to find ways to improve mitochondrial health in the context of disuse and disease. While exercise is known to cause robust improvements in mitochondrial health, not all individuals are able to exercise. This creates a need for alternate interventions which elicit some of the same benefits as exercise. Passive heating (i.e., application of heat in the absence of muscle contractions) is one potential intervention which has been shown to increase mitochondrial enzyme content and activity, and to improve mitochondrial respiration. Associated with increases in mitochondrial content and/or function, passive heating can also improve insulin sensitivity in the context of type II diabetes and preserve muscle mass in the face of limb disuse. This area of research remains in its infancy, with many questions yet to be answered about how to maximize the benefits of passive heating and elucidate the mechanisms by which heat stress affects muscle mitochondria.
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Affiliation(s)
- Erik D Marchant
- Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT, USA
| | | | | | | | - Chad R Hancock
- Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT, USA
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Collins J, Leach O, Dorff A, Linde J, Kofoed J, Sherman M, Proffit M, Gifford JR. Critical Power and Work-Prime Account for Variability in Endurance Training Adaptations Not Captured by V̇O 2MAX. J Appl Physiol (1985) 2022; 133:986-1000. [DOI: 10.1152/japplphysiol.00344.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Responses to exercise at a given percentage of one's maximum rate of oxygen consumption (V̇O2MAX), or percentage of the power associated with V̇O2MAX during a graded exercise test (i.e., PGXT), vary. Purpose: Determine if differences in Critical Power (PCRIT, maximum metabolic steady state) and Work-prime (W′, the amount of work tolerated above steady state) are related to training-induced changes in endurance. Methods: PCRIT, W′, V̇O2MAX and other variables were determined before and after 22 adults completed 8 weeks of either moderate-intensity continuous training (MICT) or high-intensity interval training (HIIT) performed at fixed percentages of PGXT. Results: On average, PCRIT increased to a greater extent following HIIT (MICT: 15.7 ± 3.1% vs. HIIT: 27.5 ± 4.3%; P=0.03), but the magnitude of change varied widely within each group (MICT: 4-36%, HIIT: 4-61%). The intensity of the prescribed exercise relative to pre-training PCRIT, not PGXT, accounted for most of the variance in changes to PCRIT in response to a given protocol (R2=0.61-0.64; P<0.01). While PCRIT and V̇O2MAX were related before training (R2=0.92, P<0.01), the training-induced change in PCRIT was not significantly related to the change in V̇O2MAX (R2=0.06, P=0.26). Before training, time-to-failure at PGXT was related to W′ (R2=0.52; P<0.01), but not V̇O2MAX (R2=0.13; P=0.10). Training-induced changes in time-to-failure at the initial PGXT were better captured by the combined changes in W′ and PCRIT (R2=0.77, P<0.01), than by the change in V̇O2MAX (R2=0.24; P=0.02). Conclusion: Differences in PCRIT and W′ account for some of the variability in responses to endurance exercise.
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Affiliation(s)
- Jessica Collins
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
| | - Olivia Leach
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
| | - Abigail Dorff
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
| | - Jessica Linde
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
| | - Jason Kofoed
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
| | - Megan Sherman
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
| | - Meagan Proffit
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
| | - Jayson R. Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
- Program of Gerontology, Brigham Young University, Provo, UT, United States
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Leach OK, Gifford JR, Mack GW. Changes In Rapid Onset Vasodilation With Baroreceptor Loading And Unloading. Med Sci Sports Exerc 2022. [DOI: 10.1249/01.mss.0000883416.54202.9d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Gifford JR, Wallace T, Dorff A, Leach O, Linde J, Kaluhiokalani J, Hyldahl R, Hancock C, Marchant E. Do Heat And Exercise Training Elicit Similar Adaptations In Vascular Function During Rest And Exercise? Med Sci Sports Exerc 2022. [DOI: 10.1249/01.mss.0000883560.91404.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Gifford JR, Wallace T, Marchant E, Kaluhiokalani J, Hyldahl R, Hancock C. The Training‐Induced Increase in Critical Power Is Strongly Related to Changes in Vascular Function in Young Adults. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r3847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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13
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Marchant ED, Hyldahl RD, Gifford JR, Hancock CR. Localized Heat Therapy Improves Mitochondrial Respiratory Capacity but Not Fat Oxidation in Human Skeletal Muscle. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r5198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Erik D. Marchant
- Nutrition, Dietetics, and Food ScienceBrigham Young UniversityProvoUT
| | | | | | - Chad R. Hancock
- Nutrition, Dietetics, and Food ScienceBrigham Young UniversityProvoUT
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Groot HJ, Broxterman RM, Gifford JR, Garten RS, Rossman MJ, Jarrett CL, Kwon OS, Hydren JR, Richardson RS. Reliability of the passive leg movement assessment of vascular function in men. Exp Physiol 2022; 107:541-552. [PMID: 35294784 PMCID: PMC9058221 DOI: 10.1113/ep090312] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 03/14/2022] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Use of the passive leg movement (PLM) test, a non-invasive assessment of microvascular function, is on the rise. However, PLM reliability in men has not been adequately investigated, nor has such reliability data, in men, been compared to the most commonly employed vascular function assessment, flow-mediated vasodilation (FMD). What is the main finding and its importance? PLM is a reliable method to assess vascular function in men, and is comparable to values previously reported for PLM in women, and for FMD. Given the importance of vascular function as a predictor of cardiovascular disease risk, these data support the utility of PLM as a clinically relevant measurement. ABSTRACT Although vascular function is an independent predictor of cardiovascular disease risk, and therefore has significant prognostic value, there is currently not a single clinically accepted method of assessment. The passive leg movement (PLM) assessment predominantly reflects microvascular endothelium-dependent vasodilation and can identify decrements in vascular function with advancing age and pathology. Reliability of the PLM model was only recently determined in women, and has not been adequately investigated in men. Twenty healthy men (age: 27 ± 2 year) were studied on three separate experimental days, resulting in three within-day and three between-day trials. The hyperemic response to PLM was assessed with Doppler ultrasound, and expressed as the absolute peak in leg blood flow (LBFpeak ), change from baseline to peak (ΔLBFpeak ), absolute area under the curve (LBFAUC ), and change in AUC from baseline (ΔLBFAUC ). PLM-induced hyperemia yielded within-day coefficients of variation (CV) from 10.9 to 22.9%, intraclass correlation coefficients (ICC) from 0.82 to 0.90, standard error of the measurement (SEM) from 8.3 to 17.2%, and Pearson's correlation coefficients (r) from 0.56 to 0.81. Between-day assessments of PLM hyperemia resulted in CV from 14.4 to 25%, ICC from 0.75 to 0.87, SEM from 9.8 to 19.8%, and r from 0.46 to 0.75. Similar to previous reports in women, the hyperemic responses to PLM in men display moderate-to-high reliability, and are comparable to reliability data for brachial artery flow mediated vasodilation. These positive reliability findings further support the utility of PLM as a clinical measurement of vascular function and cardiovascular disease risk.
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Affiliation(s)
- H. Jonathan Groot
- Department of Health & Kinesiology University of Utah, Salt Lake City, UT
| | - Ryan M. Broxterman
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, UT;,Department of Internal Medicine, University of Utah, Salt Lake City, UT
| | - Jayson R. Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, UT
| | - Ryan S. Garten
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA
| | - Matthew J. Rossman
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO
| | - Catherine L. Jarrett
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, UT;,Department of Internal Medicine, University of Utah, Salt Lake City, UT
| | - Oh Sung Kwon
- Department of Kinesiology, University of Connecticut, Storrs, CT
| | - Jay R. Hydren
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, UT;,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT
| | - Russell S. Richardson
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, UT;,Department of Internal Medicine, University of Utah, Salt Lake City, UT;,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT
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15
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Weavil JC, Thurston TS, Hureau TJ, Gifford JR, Aminizadeh S, Wan HY, Jenkinson RH, Amann M. Impact of aging on the work of breathing during exercise in healthy men. J Appl Physiol (1985) 2022; 132:689-698. [PMID: 35085030 PMCID: PMC8896992 DOI: 10.1152/japplphysiol.00443.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This study examined the impact of aging on the elastic and resistive components of the work of breathing (Wb) during locomotor exercise at a given 1) ventilatory rate, 2) metabolic rate, and 3) operating lung volume. Eight healthy younger (25 ± 4 yr) and 8 older (72 ± 6 yr) participants performed incremental bicycle exercise, from which retrospective analyses identified similar ventilatory rates (approximately 40, 70, and 100 L·min-1), similar metabolic rates (V̇o2: approximately 1.2, 1.6, and 1.9 L·min-1), and similar lung volumes [inspiratory and expiratory reserve volumes (IRV/ERV: approximately 25/34%, 16/33%, and 13-34% of vital capacity]. Wb at each level was quantified by integrating the averaged esophageal pressure-volume loop, which was then partitioned into elastic and resistive components of inspiratory and expiratory work using the modified Campbell diagram. IRV was smaller in the older participants during exercise at ventilations of 70 and 100 L·min-1 and during exercise at the three metabolic rates (P < 0.05). Mainly because of a greater inspiratory elastic and resistive Wb in the older group (P < 0.05), total Wb was augmented by 40%-50% during exercise at matched ventilatory and matched metabolic rates. When examined during exercise evoking similar lung volumes, total Wb was not different between the groups (P = 0.86). Taken together, although aging exaggerates total Wb during locomotor exercise at a given ventilatory or a given metabolic rate, this difference is abolished during exercise at a given operating lung volume. These findings highlight the significance of operating lung volume in determining the age-related difference in Wb during locomotor exercise.NEW & NOTEWORTHY This study evaluated the impact of aging on the work of breathing (Wb) during locomotor exercise evoking similar ventilatory rates, metabolic rates, and operating lung volumes in young and older individuals. Mainly because of a greater inspiratory elastic and resistive Wb in older participants, total Wb was higher during exercise at any given ventilatory and metabolic rate with aging. However, this age-related difference was abolished during exercise evoking similar operating lung volumes in both age groups. These findings highlight the significance of lung volumes in determining the age-related difference in total Wb.
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Affiliation(s)
- Joshua C. Weavil
- 1Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Salt Lake City, Utah,2Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Taylor S. Thurston
- 2Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Thomas J. Hureau
- 2Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Jayson R. Gifford
- 1Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Salt Lake City, Utah,2Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Soheil Aminizadeh
- 3Department of Physiology and Pharmacology, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Hsuan-Yu Wan
- 4Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | | | - Markus Amann
- 1Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Salt Lake City, Utah,2Department of Internal Medicine, University of Utah, Salt Lake City, Utah,4Department of Anesthesiology, University of Utah, Salt Lake City, Utah
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16
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Thurston TS, Weavil JC, Hureau TJ, Gifford JR, Georgescu VP, Wan HY, La Salle DT, Richardson RS, Amann M. On the implication of dietary nitrate supplementation for the hemodynamic and fatigue response to cycling exercise. J Appl Physiol (1985) 2021; 131:1691-1700. [PMID: 34672767 PMCID: PMC8714979 DOI: 10.1152/japplphysiol.00400.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 09/22/2021] [Accepted: 10/14/2021] [Indexed: 11/22/2022] Open
Abstract
This study investigated the impact of dietary nitrate supplementation on peripheral hemodynamics, the development of neuromuscular fatigue, and time to task failure during cycling exercise. Eleven recreationally active male participants (27 ± 5 yr, V̇o2max: 42 ± 2 mL/kg/min) performed two experimental trials following 3 days of either dietary nitrate-rich beetroot juice (4.1 mmol NO3-/day; DNS) or placebo (PLA) supplementation in a blinded, counterbalanced order. Exercise consisted of constant-load cycling at 50, 75, and 100 W (4 min each) and, at ∼80% of peak power output (218 ± 12 W), to task-failure. All participants returned to repeat the shorter of the two trials performed to task failure, but with the opposite supplementation regime (iso-time comparison; ISO). Mean arterial pressure (MAP), leg blood flow (QL; Doppler ultrasound), leg vascular conductance (LVC), and pulmonary gas exchange were continuously assessed during exercise. Locomotor muscle fatigue was determined by the change in pre to postexercise quadriceps twitch-torque (ΔQtw) and voluntary activation (ΔVA; electrical femoral nerve stimulation). Following DNS, plasma [nitrite] (∼670 vs. ∼180 nmol) and [nitrate] (∼775 vs. ∼11 μmol) were significantly elevated compared with PLA. Unlike PLA, DNS lowered both QL and MAP by ∼8% (P < 0.05), but did not alter LVC (P = 0.31). V̇O2 across work rates, as well as cycling time to task-failure (∼7 min) and locomotor muscle fatigue following the ISO-time comparison were not different between the two conditions (ΔQtw ∼42%, ΔVA ∼4%). Thus, despite significant hemodynamic changes, DNS did not alter the development of locomotor muscle fatigue and, ultimately, cycling time to task failure.NEW & NOTEWORTHY This study sought to characterize the impact of dietary nitrate supplementation on the hemodynamic response, locomotor muscle fatigue, and time to task failure during cycling exercise. Although nitrate supplementation lowered mean arterial pressure and exercising leg blood flow, leg vascular conductance and oxygen utilization were unaffected. Despite significant hemodynamic changes, there was no effect of dietary nitrate on neuromuscular fatigue development and, ultimately, cycling time to task failure.
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Affiliation(s)
- Taylor S Thurston
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Joshua C Weavil
- Geriatric Research, Education, and Clinical Center, Salt Lake City, Utah
| | - Thomas J Hureau
- Department of Medicine, University of Utah, Salt Lake City, Utah
| | - Jayson R Gifford
- Department of Medicine, University of Utah, Salt Lake City, Utah
| | - Vincent P Georgescu
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Hsuan-Yu Wan
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - D Taylor La Salle
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Russell S Richardson
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, Salt Lake City, Utah
- Department of Medicine, University of Utah, Salt Lake City, Utah
| | - Markus Amann
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, Salt Lake City, Utah
- Department of Medicine, University of Utah, Salt Lake City, Utah
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
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17
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Marchant ED, Marchant ND, Hyldahl RD, Gifford JR, Smith MW, Hancock CR. Skeletal Muscle Mitochondrial Function after a 100-km Ultramarathon: A Case Study in Monozygotic Twins. Med Sci Sports Exerc 2021; 53:2363-2373. [PMID: 34107508 DOI: 10.1249/mss.0000000000002715] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE Very little research has investigated the effects of ultraendurance exercise on the bioenergetic status of muscle. The primary objective of this case study was to characterize the changes that occur in skeletal muscle mitochondria in response to a 100-km ultramarathon in monozygotic twins. A second objective was to determine whether mitochondrial function is altered by consuming a periodized low-carbohydrate, high-fat diet during training compared with a high-carbohydrate diet. METHODS One pair of male monozygotic twins ran 100 km on treadmills after 4 wk of training on either a high-carbohydrate or periodized low-carbohydrate, high-fat diet. Muscle biopsies were collected 4 wk before the run, as well as 4 and 52 h postrun. Blood draws were also performed immediately before as well as 4 and 52 h after the run. RESULTS Four hours postrun, respiratory capacity, citrate synthase activity, and mitochondrial complex protein content were decreased. Two days later, both twins showed signs of rapid recovery in several of these measures. Furthermore, blood levels of creatine phosphokinase, C-reactive protein, and aspartate transaminase were elevated 4 h after the run but partially recovered 2 d later. CONCLUSION Although there were some differences between the twins, the primary finding is that there is significant mitochondrial impairment induced by running 100 km, which rapidly recovers within 2 d. These results provide ample rationale for future investigations of the effects of ultraendurance activity on mitochondrial function.
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Affiliation(s)
- Erik D Marchant
- Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT
| | - Nathan D Marchant
- Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT
| | | | | | - Michael W Smith
- Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT
| | - Chad R Hancock
- Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT
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18
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Lewis MT, Blain GM, Hart CR, Layec G, Rossman MJ, Park SY, Trinity JD, Gifford JR, Sidhu SK, Weavil JC, Hureau TJ, Jessop JE, Bledsoe AD, Amann M, Richardson RS. Acute high-intensity exercise and skeletal muscle mitochondrial respiratory function: role of metabolic perturbation. Am J Physiol Regul Integr Comp Physiol 2021; 321:R687-R698. [PMID: 34549627 DOI: 10.1152/ajpregu.00158.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Recently it was documented that fatiguing, high-intensity exercise resulted in a significant attenuation in maximal skeletal muscle mitochondrial respiratory capacity, potentially due to the intramuscular metabolic perturbation elicited by such intense exercise. With the utilization of intrathecal fentanyl to attenuate afferent feedback from group III/IV muscle afferents, permitting increased muscle activation and greater intramuscular metabolic disturbance, this study aimed to better elucidate the role of metabolic perturbation on mitochondrial respiratory function. Eight young, healthy males performed high-intensity cycle exercise in control (CTRL) and fentanyl-treated (FENT) conditions. Liquid chromatography-mass spectrometry and high-resolution respirometry were used to assess metabolites and mitochondrial respiratory function, respectively, pre- and postexercise in muscle biopsies from the vastus lateralis. Compared with CTRL, FENT yielded a significantly greater exercise-induced metabolic perturbation (PCr: -67% vs. -82%, Pi: 353% vs. 534%, pH: -0.22 vs. -0.31, lactate: 820% vs. 1,160%). Somewhat surprisingly, despite this greater metabolic perturbation in FENT compared with CTRL, with the only exception of respiratory control ratio (RCR) (-3% and -36%) for which the impact of FENT was significantly greater, the degree of attenuated mitochondrial respiratory capacity postexercise was not different between CTRL and FENT, respectively, as assessed by maximal respiratory flux through complex I (-15% and -33%), complex II (-36% and -23%), complex I + II (-31% and -20%), and state 3CI+CII control ratio (-24% and -39%). Although a basement effect cannot be ruled out, this failure of an augmented metabolic perturbation to extensively further attenuate mitochondrial function questions the direct role of high-intensity exercise-induced metabolite accumulation in this postexercise response.
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Affiliation(s)
- Matthew T Lewis
- Division of Geriatrics, Department of Medicine, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Gregory M Blain
- LAMHESS, University Nice Sophia Antipolis, Nice, France.,LAMHESS, University of Toulon, La Garde, France
| | - Corey R Hart
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Gwenael Layec
- Division of Geriatrics, Department of Medicine, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Matthew J Rossman
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Song-Young Park
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah.,School of Health and Kinesiology, University of Nebraska, Omaha, Nebraska
| | - Joel D Trinity
- Division of Geriatrics, Department of Medicine, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Jayson R Gifford
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Simranjit K Sidhu
- Division of Geriatrics, Department of Medicine, University of Utah, Salt Lake City, Utah.,Discipline of Physiology, School of Medicine, University of Adelaide, Adelaide, South Australia, Australia
| | - Joshua C Weavil
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Thomas J Hureau
- Division of Geriatrics, Department of Medicine, University of Utah, Salt Lake City, Utah.,LAMHESS, University Nice Sophia Antipolis, Nice, France.,LAMHESS, University of Toulon, La Garde, France
| | - Jacob E Jessop
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Amber D Bledsoe
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Markus Amann
- Division of Geriatrics, Department of Medicine, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah.,Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Russell S Richardson
- Division of Geriatrics, Department of Medicine, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
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19
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Hyldahl RD, Hafen PS, Nelson WB, Ahmadi M, Pfeifer B, Mehling J, Gifford JR. Passive muscle heating attenuates the decline in vascular function caused by limb disuse. J Physiol 2021; 599:4581-4596. [PMID: 34487346 DOI: 10.1113/jp281900] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 08/31/2021] [Indexed: 01/16/2023] Open
Abstract
Limb disuse has profound negative consequences on both vascular and skeletal muscle health. The purpose of this investigation was to determine whether repeated application of passive heat, applied to the knee extensor muscles, could mitigate the detrimental effects of limb disuse on vascular function. This was a randomized, single-blinded placebo controlled trial. Twenty-one healthy volunteers (10 women, 11 men) underwent 10 days of unilateral lower limb immobilization and were randomized to receive either a daily 2 h sham (Imm) or heat treatment (Imm+H) using pulsed shortwave diathermy. Vascular function was assessed with Doppler ultrasound of the femoral artery and the passive leg movement technique. Biopsies of the vastus lateralis were also collected before and after the intervention. In Imm, femoral artery diameter (FAD) and PLM-induced hyperaemia (HYP) were reduced by 7.3% and 34.3%, respectively. Changes in both FAD (4% decrease; P = 0.0006) and HYP (7.8% increase; P = 0.003) were significantly attenuated in Imm+H. Vastus lateralis capillary density was not altered in either group. Immobilization significantly decreased expression of vascular endothelial growth factor (P = 0.006) and Akt (P = 0.001), and increased expression of angiopoietin 2 (P = 0.0004) over time, with no differences found between groups. Immobilization also upregulated elements associated with remodelling of the extracellular matrix, including matrix metalloproteinase 2 (P = 0.0046) and fibronectin (P = 0.0163), with no differences found between groups. In conclusion, limb immobilization impairs vascular endothelial function, but daily muscle heating via diathermy is sufficient to counteract this adverse effect. These are the first data to indicate that passive muscle heating mitigates disuse-induced vascular dysfunction. KEY POINTS: Limb disuse can be unavoidable for many of reasons (i.e. injury, bed rest, post-surgery), and can have significant adverse consequences for muscular and vascular health. We tested the hypothesis that declines in vascular function that result from lower limb immobilization could be mitigated by application of passive heat therapy. This report shows that 10 days of limb immobilization significantly decreases resistance artery diameter and vascular function, and that application of passive heat to the knee extensor muscle group each day for 2 h per day is sufficient to attenuate these declines. Additionally, muscle biopsy analyses showed that 10 days of heat therapy does not alter capillary density of the muscle, but upregulates multiple factors indicative of a vascular remodelling response. Our data demonstrate the utility of passive heat as a therapeutic tool to mitigate losses in lower limb vascular function that occur from disuse.
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Affiliation(s)
- Robert D Hyldahl
- Department of Exercise Sciences, Brigham Young University, Provo, UT, USA
| | - Paul S Hafen
- Department of Exercise Sciences, Brigham Young University, Provo, UT, USA
| | - W Bradley Nelson
- Department of Exercise Sciences, Brigham Young University, Provo, UT, USA
| | - Mohadeseh Ahmadi
- Department of Exercise Sciences, Brigham Young University, Provo, UT, USA
| | - Brandon Pfeifer
- Department of Exercise Sciences, Brigham Young University, Provo, UT, USA
| | - Jack Mehling
- Department of Exercise Sciences, Brigham Young University, Provo, UT, USA
| | - Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, UT, USA
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20
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Gifford JR, Collins J, Dorff A, Leach O, Kofoed J, Sherman M, Quirante J, Proffit M. Effect Of High-intensity Vs. Moderate-intensity Endurance Training On Critical Power In Untrained, Young Adults. Med Sci Sports Exerc 2021. [DOI: 10.1249/01.mss.0000759364.58972.bc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Abstract
PURPOSE This study aimed to determine how the speed-distance relationship, described by critical speed (CS) and distance prime (D'), is altered with aging. METHODS Official race data from the past eight World Masters Athletics Indoor Track and Field World Championships were used for this study. CS and D' were calculated for female and male athletes (35-90 yr of age) who registered times for the 800-, 1500-, and 3000-m runs during a single championship to determine the relationship between age and CS and D'. Twenty-six athletes completed sufficient races in multiple championships to retrospectively assess the change in CS and D' over time. RESULTS Cross-sectional data indicated that CS continuously decreases after age 35 yr in a curvilinear manner with advancing age (R2 = 0.73, P < 0.001, n = 187), with even greater decreases in CS occurring after ~70 yr of age. D' also changed in a curvilinear manner with age (R2 = 0.45, P < 0.001, n = 103), such that decreases were observed between 35 and 70 yr, followed by an increase in D' thereafter. Retrospective, longitudinal data, with an average follow-up of 6.38 ± 1.73 yr, support these findings, indicating that the annual decrease in CS grows with advancing age (e.g., ~1% vs ~3% annual decrease in CS at age 55 vs 80 yr, respectively) and that D' shifts from an annual decrease (e.g., ~2.5% annual decrease at 55 yr) to an annual increase (e.g., ~2.5% annual increase at 80 yr) around 70 yr of age. Importantly, the relationship between CS and race pace was unaffected by age, supporting the relevance of CS throughout aging. CONCLUSION Even among world-class athletes, CS decreases and D' changes with aging. These adaptations may contribute to the diminished exercise ability associated with aging.
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Affiliation(s)
| | - Jessica Collins
- Department of Exercise Sciences, Brigham Young University, Provo, UT
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22
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Hydren JR, Gifford JR, Jarrett CL, Park SH, Shields KL, Broxterman RM, Kithas AC, Bisconti AV, Thurston TS, Ratchford SM, Wray DW, Stehlik J, Selzman CH, Drakos SG, Richardson RS. Vascular function in continuous-flow left ventricular assist device recipients: effect of a single pulsatility treatment session. Am J Physiol Regul Integr Comp Physiol 2021; 320:R425-R437. [PMID: 33438517 DOI: 10.1152/ajpregu.00274.2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vascular function is further attenuated in patients with chronic heart failure implanted with a continuous-flow left ventricular assist device (LVAD), likely due to decreased arterial pulsatility, and this may contribute to LVAD-associated cardiovascular complications. However, the impact of increasing pulsatility on vascular function in this population is unknown. Therefore, 15 LVAD recipients and 15 well-matched controls underwent a 45-min, unilateral, arm pulsatility treatment, evoked by intermittent cuff inflation/deflation (2-s duty cycle), distal to the elbow. Vascular function was assessed by percent brachial artery flow-mediated dilation (%FMD) and reactive hyperemia (RH) (Doppler ultrasound). Pretreatment, %FMD (LVAD: 4.0 ± 1.7; controls: 4.2 ± 1.4%) and RH (LVAD: 340 ± 101; controls: 308 ± 94 mL) were not different between LVAD recipients and controls; however, %FMD/shear rate was attenuated (LVAD: 0.10 ± 0.04; controls: 0.17 ± 0.06%/s-1, P < 0.05). The LVAD recipients exhibited a significantly attenuated pulsatility index (PI) compared with controls prior to treatment (LVAD: 2 ± 2; controls: 15 ± 7 AU, P < 0.05); however, during the treatment, PI was no longer different (LVAD: 37 ± 38; controls: 36 ± 14 AU). Although time to peak dilation and RH were not altered by the pulsatility treatment, %FMD (LVAD: 7.0 ± 1.8; controls: 7.4 ± 2.6%) and %FMD/shear rate (LVAD: 0.19 ± 0.07; controls: 0.33 ± 0.15%/s-1) increased significantly in both groups, with, importantly, %FMD/shear rate in the LVAD recipients being restored to that of the controls pretreatment. This study documents that a localized pulsatility treatment in LVAD recipients and controls can recover local vascular function, an important precursor to the development of approaches to increase systemic pulsatility and reduce systemic vascular complications in LVAD recipients.
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Affiliation(s)
- Jay R Hydren
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Catherine L Jarrett
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Soung Hun Park
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Katherine L Shields
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Ryan M Broxterman
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Andrew C Kithas
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Angela Valentina Bisconti
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Taylor S Thurston
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Stephen M Ratchford
- Department of Health and Exercise Science, Appalachian State University, Boone, North Carolina
| | - D Walter Wray
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Josef Stehlik
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Craig H Selzman
- Department of Surgery, University of Utah School of Medicine, Salt Lake City, Utah
| | - Stavros G Drakos
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Russell S Richardson
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah
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23
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Trinity JD, Kwon OS, Broxterman RM, Gifford JR, Kithas AC, Hydren JR, Jarrett CL, Shields KL, Bisconti AV, Park SH, Craig JC, Nelson AD, Morgan DE, Jessop JE, Bledsoe AD, Richardson RS. The role of the endothelium in the hyperemic response to passive leg movement: looking beyond nitric oxide. Am J Physiol Heart Circ Physiol 2020; 320:H668-H678. [PMID: 33306447 DOI: 10.1152/ajpheart.00784.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Passive leg movement (PLM) evokes a robust and predominantly nitric oxide (NO)-mediated increase in blood flow that declines with age and disease. Consequently, PLM is becoming increasingly accepted as a sensitive assessment of endothelium-mediated vascular function. However, a substantial PLM-induced hyperemic response is still evoked despite nitric oxide synthase (NOS) inhibition. Therefore, in nine young healthy men (25 ± 4 yr), this investigation aimed to determine whether the combination of two potent endothelium-dependent vasodilators, specifically prostaglandin (PG) and endothelium-derived hyperpolarizing factor (EDHF), account for the remaining hyperemic response to the two variants of PLM, PLM (60 movements) and single PLM (sPLM, 1 movement), when NOS is inhibited. The leg blood flow (LBF, Doppler ultrasound) response to PLM and sPLM following the intra-arterial infusion of NG-monomethyl-l-arginine (l-NMMA), to inhibit NOS, was compared to the combined inhibition of NOS, cyclooxygenase (COX), and cytochrome P-450 (CYP450) by l-NMMA, ketorolac tromethamine (KET), and fluconazole (FLUC), respectively. NOS inhibition attenuated the overall LBF [area under the curve (LBFAUC)] response to both PLM (control: 456 ± 194, l-NMMA: 168 ± 127 mL, P < 0.01) and sPLM (control: 185 ± 171, l-NMMA: 62 ± 31 mL, P = 0.03). The combined inhibition of NOS, COX, and CYP450 (i.e., l-NMMA+KET+FLUC) did not further attenuate the hyperemic responses to PLM (LBFAUC: 271 ± 97 mL, P > 0.05) or sPLM (LBFAUC: 72 ± 45 mL, P > 0.05). Therefore, PG and EDHF do not collectively contribute to the non-NOS-derived NO-mediated, endothelium-dependent hyperemic response to either PLM or sPLM in healthy young men. These findings add to the mounting evidence and understanding of the vasodilatory pathways assessed by the PLM and sPLM vascular function tests.NEW & NOTEWORTHY Passive leg movement (PLM) evokes a highly nitric oxide (NO)-mediated hyperemic response and may provide a novel evaluation of vascular function. The contributions of endothelium-dependent vasodilatory pathways, beyond NO and including prostaglandins and endothelium-derived hyperpolarizing factor, to the PLM-induced hyperemic response to PLM have not been evaluated. With intra-arterial drug infusion, the combined inhibition of nitric oxide synthase (NOS), cyclooxygenase, and cytochrome P-450 (CYP450) pathways did not further diminish the hyperemic response to PLM compared with NOS inhibition alone.
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Affiliation(s)
- Joel D Trinity
- Geriatric Research, Education, and Clinical Center, Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Oh Sung Kwon
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Kinesiology, University of Connecticut, Storrs, Connecticut
| | - Ryan M Broxterman
- Geriatric Research, Education, and Clinical Center, Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Jayson R Gifford
- Geriatric Research, Education, and Clinical Center, Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Exercise Science, Brigham Young University, Provo, Utah
| | - Andrew C Kithas
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Jay R Hydren
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Catherine L Jarrett
- Geriatric Research, Education, and Clinical Center, Department of Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Katherine L Shields
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Angela V Bisconti
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Soung Hun Park
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Jesse C Craig
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Ashley D Nelson
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - David E Morgan
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Jacob E Jessop
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Amber D Bledsoe
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
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Weavil JC, Thurston TS, Hureau TJ, Gifford JR, Kithas PA, Broxterman RM, Bledsoe AD, Nativi JN, Richardson RS, Amann M. Heart failure with preserved ejection fraction diminishes peripheral hemodynamics and accelerates exercise-induced neuromuscular fatigue. Am J Physiol Heart Circ Physiol 2020; 320:H338-H351. [PMID: 33164549 DOI: 10.1152/ajpheart.00266.2020] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
This study investigated the impact of HFpEF on neuromuscular fatigue and peripheral hemodynamics during small muscle mass exercise not limited by cardiac output. Eight HFpEF patients (NYHA II-III, ejection-fraction: 61 ± 2%) and eight healthy controls performed dynamic knee extension exercise (80% peak workload) to task failure and maximal intermittent quadriceps contractions (8 × 15 s). Controls repeated knee extension at the same absolute intensity as HFpEF. Leg blood flow (QL) was quantified using Doppler ultrasound. Pre/postexercise changes in quadriceps twitch torque (ΔQtw; peripheral fatigue), voluntary activation (ΔVA; central fatigue), and corticospinal excitability were quantified. At the same relative intensity, HFpEF (24 ± 5 W) and controls (42 ± 6 W) had a similar time-to-task failure (∼10 min), ΔQtw (∼50%), and ΔVA (∼6%). This resulted in a greater exercise-induced change in neuromuscular function per unit work in HFpEF, which was significantly correlated with a slower QL response time. Knee extension exercise at the same absolute intensity resulted in an ∼40% lower QL and greater ΔQtw and ΔVA in HFpEF than in controls. Corticospinal excitability remained unaltered during exercise in both groups. Finally, despite a similar ΔVA, ΔQtw was larger in HFpEF versus controls during isometric exercise. In conclusion, HFpEF patients are characterized by a similar development of central and peripheral fatigue as healthy controls when tested at the same relative intensity during exercise not limited by cardiac output. However, HFpEF patients have a greater susceptibility to neuromuscular fatigue during exercise at a given absolute intensity, and this impairs functional capacity. The patients' compromised QL response to exercise likely accounts, at least partly, for the patients' attenuated fatigue resistance.NEW & NOTEWORTHY The susceptibility to neuromuscular fatigue during exercise is substantially exaggerated in individuals with heart failure with a preserved ejection fraction. The faster rate of fatigue development is associated with the compromised peripheral hemodynamic response characterizing these patients during exercise. Given the role of neuromuscular fatigue as a factor limiting exercise, this impairment likely accounts for a significant portion of the exercise intolerance typical for this population.
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Affiliation(s)
- J C Weavil
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - T S Thurston
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - T J Hureau
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - J R Gifford
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - P A Kithas
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - R M Broxterman
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - A D Bledsoe
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - J N Nativi
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - R S Richardson
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - M Amann
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah.,Department of Anesthesiology, University of Utah, Salt Lake City, Utah
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25
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Kithas AC, Broxterman RM, Trinity JD, Gifford JR, Kwon OS, Hydren JR, Nelson AD, Jessop JE, Bledsoe AD, Morgan DE, Richardson RS. Nitric oxide synthase inhibition with N(G)-monomethyl-l-arginine: Determining the window of effect in the human vasculature. Nitric Oxide 2020; 104-105:51-60. [PMID: 32979497 DOI: 10.1016/j.niox.2020.09.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 09/07/2020] [Accepted: 09/21/2020] [Indexed: 11/17/2022]
Abstract
Nitric oxide synthase (NOS) inhibition with N(G)-monomethyl-l-arginine (L-NMMA) is often used to assess the role of NO in human cardiovascular function. However, the window of effect for L-NMMA on human vascular function is unknown, which is critical for designing and interpreting human-based studies. This study utilized the passive leg movement (PLM) assessment of vascular function, which is predominantly NO-mediated, in 7 young male subjects under control conditions, immediately following intra-arterial L-NMMA infusion (0.24 mg⋅dl-1⋅min-1), and at 45-60 and 90-105 min post L-NMMA infusion. The leg blood flow (LBF) and leg vascular conductance (LVC) responses to PLM, measured with Doppler ultrasound and expressed as the change from baseline to peak (ΔLBFpeak and ΔLVCpeak) and area under the curve (LBFAUC and LVCACU), were assessed. PLM-induced robust control ΔLBFpeak (1135 ± 324 ml⋅min-1) and ΔLVCpeak (10.7 ± 3.6 ml⋅min-1⋅mmHg-1) responses that were significantly attenuated (704 ± 196 ml⋅min-1 and 6.7 ± 2 ml⋅min-1⋅mmHg-1) immediately following L-NMMA infusion. Likewise, control condition PLM ΔLBFAUC (455 ± 202 ml) and ΔLVCAUC (4.0 ± 1.4 ml⋅mmHg-1) were significantly attenuated (141 ± 130 ml and 1.3 ± 1.2 ml⋅mmHg-1) immediately following L-NMMA infusion. However, by 45-60 min post L-NMMA infusion all PLM variables were not significantly different from control, and this was still the case at 90-105 min post L-NMMA infusion. These findings reveal that the potent reduction in NO bioavailability afforded by NOS inhibition with L-NMMA has a window of effect of less than 45-60 min in the human vasculature. These data are particularly important for the commonly employed approach of pharmacologically inhibiting NOS with L-NMMA in the human vasculature.
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Affiliation(s)
- Andrew C Kithas
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Ryan M Broxterman
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA; Geriatric Research, Education, and Clinical Center, Salt Lake City, VAMC, UT, USA
| | - Joel D Trinity
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA; Department of Nutrition and Integrative Physiology, USA; Geriatric Research, Education, and Clinical Center, Salt Lake City, VAMC, UT, USA
| | - Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, UT, USA
| | - Oh Sung Kwon
- Department of Kinesiology, University of Connecticut, Storrs, CT, USA
| | - Jay R Hydren
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA; Department of Nutrition and Integrative Physiology, USA; Geriatric Research, Education, and Clinical Center, Salt Lake City, VAMC, UT, USA
| | - Ashley D Nelson
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Jacob E Jessop
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Amber D Bledsoe
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - David E Morgan
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Russell S Richardson
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA; Department of Nutrition and Integrative Physiology, USA; Geriatric Research, Education, and Clinical Center, Salt Lake City, VAMC, UT, USA.
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26
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Gifford JR, Hanson BE, Proffit M, Wallace T, Kofoed J, Griffin G, Hanson M. Indices of leg resistance artery function are independently related to cycling V̇O 2 max. Physiol Rep 2020; 8:e14551. [PMID: 32812353 PMCID: PMC7435036 DOI: 10.14814/phy2.14551] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 07/26/2020] [Indexed: 12/30/2022] Open
Abstract
PURPOSE While maximum blood flow influences one's maximum rate of oxygen consumption (V̇O2 max), with so many indices of vascular function, it is still unclear if vascular function is related to V̇O2 max in healthy, young adults. The purpose of this study was to determine if several common vascular tests of conduit artery and resistance artery function provide similar information about vascular function and the relationship between vascular function and V̇O2 max. METHODS Twenty-two healthy adults completed multiple assessments of leg vascular function, including flow-mediated dilation (FMD), reactive hyperemia (RH), passive leg movement (PLM), and rapid onset vasodilation (ROV). V̇O2 max was assessed with a graded exercise test on a cycle ergometer. RESULTS Indices associated with resistance artery function (e.g., peak flow during RH, PLM, and ROV) were generally related to each other (r = 0.47-77, p < .05), while indices derived from FMD were unrelated to other tests (p < .05). Absolute V̇O2 max (r = 0.57-0.73, p < .05) and mass-specific V̇O2 max (r = 0.41-0.46, p < .05) were related to indices of resistance artery function, even when controlling for factors like body mass and sex. FMD was only related to mass-specific V̇O2 max after statistically controlling for baseline artery diameter (r = 0.44, p < .05). CONCLUSION Indices of leg resistance artery function (e.g., peak flow during RH, PLM, and ROV) relate well to each other and account for ~30% of the variance in V̇O2 max not accounted for by other factors, like body mass and sex. Vascular interventions should focus on improving indices of resistance artery function, not conduit artery function, when seeking to improve exercise capacity.
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Affiliation(s)
- Jayson R. Gifford
- Department of Exercise SciencesBrigham Young UniversityProvoUTUSA
- Program of GerontologyBrigham Young UniversityProvoUTUSA
| | - Brady E. Hanson
- Department of Exercise SciencesBrigham Young UniversityProvoUTUSA
| | - Meagan Proffit
- Department of Exercise SciencesBrigham Young UniversityProvoUTUSA
- Program of GerontologyBrigham Young UniversityProvoUTUSA
| | - Taysom Wallace
- Department of Exercise SciencesBrigham Young UniversityProvoUTUSA
| | - Jason Kofoed
- Department of Exercise SciencesBrigham Young UniversityProvoUTUSA
| | - Garrett Griffin
- Department of Exercise SciencesBrigham Young UniversityProvoUTUSA
| | - Melina Hanson
- Department of Exercise SciencesBrigham Young UniversityProvoUTUSA
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27
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Gifford JR, Collins J. The Impact Of Age On Critical Speed And Distance’: Insight From The Masters World Championships. Med Sci Sports Exerc 2020. [DOI: 10.1249/01.mss.0000682860.45936.7b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Affiliation(s)
- Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, UT, USA.,Program of Gerontology, Brigham Young University, Provo, UT, USA
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Gifford JR, Johnson AW, Mitchell U, Feland JB. Response. Med Sci Sports Exerc 2020; 52:1437. [DOI: 10.1249/mss.0000000000002317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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30
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Jarrett CL, Shields KL, Broxterman RM, Hydren JR, Park SH, Gifford JR, Richardson RS. Imaging transcranial Doppler ultrasound to measure middle cerebral artery blood flow: the importance of measuring vessel diameter. Am J Physiol Regul Integr Comp Physiol 2020; 319:R33-R42. [PMID: 32401627 DOI: 10.1152/ajpregu.00025.2020] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cerebral blood flow (CBF) is commonly inferred from blood velocity measurements in the middle cerebral artery (MCA), using nonimaging, transcranial Doppler ultrasound (TCD). However, both blood velocity and vessel diameter are critical components required to accurately determine blood flow, and there is mounting evidence that the MCA is vasoactive. Therefore, the aim of this study was to employ imaging TCD (ITCD), utilizing color flow images and pulse wave velocity, as a novel approach to measure both MCA diameter and blood velocity to accurately quantify changes in MCA blood flow. ITCD was performed at rest in 13 healthy participants (7 men/6 women; 28 ± 5 yr) with pharmaceutically induced vasodilation [nitroglycerin (NTG), 0.8 mg] and without (CON). Measurements were taken for 2 min before and for 5 min following NTG or sham delivery (CON). There was more than a fivefold, significant, fall in MCA blood velocity in response to NTG (∆-4.95 ± 4.6 cm/s) compared to negligible fluctuation in CON (∆-0.88 ± 4.7 cm/s) (P < 0.001). MCA diameter increased significantly in response to NTG (∆0.09 ± 0.04 cm) compared with the basal variation in CON (∆0.00 ± 0.04 cm) (P = 0.018). Interestingly, the product of the NTG-induced fall in MCA blood velocity and increase in diameter was a significant increase in MCA blood flow following NTG (∆144 ± 159 ml/min) compared with CON (∆-5 ± 130 ml/min) (P = 0.005). These juxtaposed findings highlight the importance of measuring both MCA blood velocity and diameter when assessing CBF and document ITCD as a novel approach to achieve this goal.
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Affiliation(s)
- Catherine L Jarrett
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Katherine L Shields
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Ryan M Broxterman
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Jay R Hydren
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Soung Hun Park
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Russell S Richardson
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah
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31
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Gifford JR, Bloomfield T, Davis T, Addington A, McMullin E, Wallace T, Proffit M, Hanson B. The effect of the speed and range of motion of movement on the hyperemic response to passive leg movement. Physiol Rep 2020; 7:e14064. [PMID: 31004411 PMCID: PMC6474844 DOI: 10.14814/phy2.14064] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 03/27/2019] [Indexed: 11/24/2022] Open
Abstract
Passive leg movement (PLM)-induced hyperemia is used to assess the function of the vascular endothelium. This study sought to determine the impact of movement speed and range of motion (ROM) on the hyperemic response to PLM and determine if the currently recommended protocol of moving the leg through a 90° ROM at 180°/sec provides a peak hyperemic response to PLM. 11 healthy adults underwent multiple bouts of PLM, in which either movement speed (60-240°/sec) or ROM (30-120° knee flexion) were varied. Femoral artery blood flow (Doppler Ultrasound) and mean arterial pressure (MAP; photoplethysmography) were measured throughout. Movement speed generally exhibited positive linear relationships with the hyperemic response to PLM, eliciting ~15-20% increase in hyperemia and conductance for each 30°/sec increase in speed (P < 0.05). However, increasing the movement speed above 180°/sec was physically difficult and seemingly impractical to implement. ROM exhibited curvilinear relationships (P<0.05) with hyperemia and conductance, which peaked at 90°, such that a 30° increase or decrease in ROM from 90° resulted in a 10-40% attenuation (P < 0.05) in the hyperemic response. Alterations in the balance of antegrade and retrograde flow appear to play a role in this attenuation. Movement speed and ROM have a profound impact on PLM-induced hyperemia. When using PLM to assess vascular endothelial function, it is recommended to perform the test at the traditional 180°/sec with 90° ROM, which offers a near peak hyperemic response, while maintaining test feasibility.
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Affiliation(s)
- Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, Utah.,Program of Gerontology, Brigham Young University, Provo, Utah
| | - Travis Bloomfield
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Trevor Davis
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Amy Addington
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Erin McMullin
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Taysom Wallace
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Meagan Proffit
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Brady Hanson
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
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Ives SJ, Layec G, Hart CR, Trinity JD, Gifford JR, Garten RS, Witman MAH, Sorensen JR, Richardson RS. Passive leg movement in chronic obstructive pulmonary disease: evidence of locomotor muscle vascular dysfunction. J Appl Physiol (1985) 2020; 128:1402-1411. [PMID: 32324478 DOI: 10.1152/japplphysiol.00568.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Chronic obstructive pulmonary disease (COPD), characterized by pulmonary dysfunction, is now also recognized to be associated with free radical-mediated vascular dysfunction. However, as previous investigations have utilized the brachial artery flow-mediated dilation technique, whether such vascular dysfunction exists in the locomotor muscle of patients with COPD remains unclear. Therefore, in patients with COPD (n = 13, 66 ± 6 yr) and healthy age- and sex-matched control subjects (n = 12, 68 ± 6 yr), second-by-second measurements of leg blood flow (LBF) (ultrasound Doppler), mean arterial pressure (MAP) (Finapres), and leg vascular conductance (LVC) were recorded before and during both 2 min of continuous upright seated continuous-movement passive leg movement (PLM) and a single-movement PLM (sPLM). In response to PLM, both peak change in LBF (COPD 321 ± 54, Control 470 ± 55 ∆mL/min) and LVC (COPD 3.0 ± 0.5, Control 5.4 ± 0.5 ∆mL·min-1·mmHg-1) were significantly attenuated in patients with COPD compared with control subjects (P < 0.05). This attenuation in the patients with COPD was also evident in response to sPLM, with peak change in LBF tending to be lower (COPD 142 ± 26, Control 169 ± 14 ∆mL/min) and LVC being significantly lower (P < 0.05) in the patients than the control subjects (COPD 1.6 ± 0.4, Control 2.5 ± 0.3 ∆mL·min-1·mmHg-1). Therefore, utilizing both PLM and sPLM, this study provides evidence of locomotor muscle vascular dysfunction in patients with COPD, perhaps due to redox imbalance and reduced nitric oxide bioavailability, which is in agreement with an increased cardiovascular disease risk in this population. This locomotor muscle vascular dysfunction, in combination with the clearly dysfunctional lungs, may contribute to the exercise intolerance associated with COPD.NEW & NOTEWORTHY Utilizing both the single and continuous passive leg movement (PLM) models, which induce nitric oxide (NO)-dependent hyperemia, this study provides evidence of vascular dysfunction in the locomotor muscle of patients with chronic obstructive pulmonary disease (COPD), independent of central hemodynamics. This impaired hyperemia may be the result of an oxidant-mediated attenuation in NO bioavailability. In addition to clearly dysfunctional lungs, vascular dysfunction in locomotor muscle may contribute to the exercise intolerance associated with COPD and increased cardiovascular disease risk.
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Affiliation(s)
- Stephen J Ives
- Geriatric Research, Education, and Clinical Center, George E. Whalen Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Health and Human Physiological Sciences Department, Skidmore College, Saratoga Springs, New York
| | - Gwenael Layec
- Geriatric Research, Education, and Clinical Center, George E. Whalen Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Corey R Hart
- Geriatric Research, Education, and Clinical Center, George E. Whalen Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Joel D Trinity
- Geriatric Research, Education, and Clinical Center, George E. Whalen Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Jayson R Gifford
- Geriatric Research, Education, and Clinical Center, George E. Whalen Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Ryan S Garten
- Geriatric Research, Education, and Clinical Center, George E. Whalen Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, Virginia
| | - Melissa A H Witman
- Geriatric Research, Education, and Clinical Center, George E. Whalen Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Kinesiology and Applied Physiology, University of Delaware, Wilmington, Delaware
| | - Jacob R Sorensen
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, George E. Whalen Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
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Hydren JR, Gifford JR, Jarrett CL, Park SH, Shields KL, Broxterman RM, Kithas AC, Bisconti AV, Thurston TS, Ratchford SM, Wray DW, Stehlik J, Selzman CH, Drakos SG, Richardson RS. Vascular Function in Continuous‐Flow Left Ventricular Assist Device Recipients: Effect of a 6‐Week Pulsatility Treatment Regimen. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.02772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Hanson BE, Proffit M, Gifford JR. Vascular function is related to blood flow during high-intensity, but not low-intensity, knee extension exercise. J Appl Physiol (1985) 2020; 128:698-708. [DOI: 10.1152/japplphysiol.00671.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
While vascular function, assessed as the ability of the vasculature to dilate in response to a stimulus, is related to cardiovascular health, its relationship to exercise hyperemia is unclear. This study sought to determine if blood flow during submaximal and maximal exercise is related to vascular function. Nineteen healthy adults completed multiple assessments of vascular function specific to the leg, including passive leg movement (PLM), rapid onset vasodilation (ROV), reactive hyperemia (RH), and flow-mediated dilation (FMD). On a separate day, exercise blood flow (Doppler ultrasound) was assessed in the same leg during various intensities of single-leg, knee-extension (KE) exercise. Vascular function, determined by PLM, ROV, and RH, was related to exercise blood flow at high intensities, including maximum work rate (WRmax) ( r = 0.58–0.77, P < 0.001), but not low intensities, like ~21% WRmax ( r = 0.12–0.34, P = 0.12–0.62). Relationships between multiple indices of vascular function and peak exercise blood flow persisted when controlling for quadriceps mass and exercise work rate ( P < 0.05), indicating vascular function is independently related to the blood flow response to intense exercise. When divided into two groups based upon the magnitude of the PLM response, subjects with a lower PLM response exhibited lower exercise flow at several absolute work rates, as well as lower peak flow ( P < 0.05). In conclusion, leg flow during dynamic exercise is independently correlated with multiple different indices of microvascular function. Thus microvascular function appears to modulate the hyperemic response to high-intensity, but not low-intensity, exercise. NEW & NOTEWORTHY While substantial evidence indicates that individuals with lower vascular function are at greater risk for cardiovascular disease, with many redundant vasodilator pathways present during exercise, it has been unclear if low vascular function actually impacts blood flow during exercise. This study provides evidence that vascular function, assessed by multiple noninvasive methods, is related to the blood flow response to high-intensity leg exercise in healthy young adults. Importantly, healthy young adults with lower levels of vascular function, particularly microvascular function, exhibit lower blood flow during high-intensity, and maximal knee extension exercise. Thus it appears that in addition to increasing one’s risk of cardiovascular disease, lower vascular function is also related to a blunted blood flow response during high-intensity exercise.
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Affiliation(s)
- Brady E. Hanson
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Meagan Proffit
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - Jayson R. Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
- Program of Gerontology, Brigham Young University, Provo, Utah
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Craig JC, Broxterman RM, La Salle DT, Cerbie J, Ratchford SM, Gifford JR, Bunsawat K, Nelson AD, Bledsoe AD, Morgan DE, Wray DW, Richardson RS, Trinity JD. The role of endothelin A receptors in peripheral vascular control at rest and during exercise in patients with hypertension. J Physiol 2019; 598:71-84. [PMID: 31705661 DOI: 10.1113/jp279077] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 11/01/2019] [Indexed: 12/21/2022] Open
Abstract
KEY POINTS Exercise in patients with hypertension can be accompanied by an abnormal cardiovascular response that includes attenuated blood flow and an augmented pressor response. Endothelin-1, a very potent vasoconstrictor, is a key modulator of blood flow and pressure during in health and has been implicated as a potential cause of the dysfunction in hypertension. We assessed the role of endothelin-1, acting through endothelin A (ETA ) receptors, in modulating the central and peripheral cardiovascular responses to exercise in patients with hypertension via local antagonism of these receptors during exercise. ETA receptor antagonism markedly increased leg blood flow, vascular conductance, oxygen delivery, and oxygen consumption during exercise; interestingly, these changes occurred in the presence of reduced leg perfusion pressure, indicating that these augmentations were driven by changes in vascular resistance. These data indicate that ETA receptor antagonism could be a viable therapeutic approach to improve blood flow during exercise in hypertension. ABSTRACT Patients with hypertension can exhibit impaired muscle blood flow and exaggerated increases in blood pressure during exercise. While endothelin (ET)-1 plays a role in regulating blood flow and pressure during exercise in health, little is known about the role of ET-1 in the cardiovascular response to exercise in hypertension. Therefore, eight volunteers diagnosed with hypertension were studied during exercise with either saline or BQ-123 (ETA receptor antagonist) infusion following a 2-week withdrawal of anti-hypertensive medications. The common femoral artery and vein were catheterized for drug infusion, blood collection and blood pressure measurements, and leg blood flow was measured by Doppler ultrasound. Patients exercised at both absolute (0, 5, 10, 15 W) and relative (40, 60, 80% peak power) intensities. BQ-123 increased blood flow at rest (79 ± 87 ml/min; P = 0.03) and augmented the exercise-induced hyperaemia at most intensities (80% saline: Δ3818±1222 vs. BQ-123: Δ4812±1469 ml/min; P = 0.001). BQ-123 reduced leg MAP at rest (-8 ± 4 mmHg; P < 0.001) and lower intensities (0-10 W; P < 0.05). Systemic diastolic blood pressure was reduced (0 W, 40%; P < 0.05), but systemic MAP was defended by an increased cardiac output. The exercise pressor response (ΔMAP) did not differ between conditions (80% saline: 25 ± 10, BQ-123: 30 ± 7 mmHg; P = 0.17). Thus, ET-1, acting through the ETA receptors, contributes to the control of blood pressure at rest and lower intensity exercise in these patients. Furthermore, the finding that ET-1 constrains the blood flow response to exercise suggests that ETA receptor antagonism could be a therapeutic approach to improve blood flow during exercise in hypertension.
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Affiliation(s)
- Jesse C Craig
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Ryan M Broxterman
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah, USA
| | - D Taylor La Salle
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, USA
| | - James Cerbie
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, USA
| | - Stephen M Ratchford
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah, USA
| | - Jayson R Gifford
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah, USA
| | - Kanokwan Bunsawat
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Ashley D Nelson
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah, USA
| | - Amber D Bledsoe
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah, USA
| | - David E Morgan
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah, USA
| | - D Walter Wray
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah, USA.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, USA
| | - Russell S Richardson
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah, USA.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, USA
| | - Joel D Trinity
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah, USA.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, USA
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Jacobs JL, Ridge ST, Bruening DA, Brewerton KA, Gifford JR, Hoopes DM, Johnson AW. Passive hallux adduction decreases lateral plantar artery blood flow: a preliminary study of the potential influence of narrow toe box shoes. J Foot Ankle Res 2019; 12:50. [PMID: 31700547 PMCID: PMC6829837 DOI: 10.1186/s13047-019-0361-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 10/04/2019] [Indexed: 11/10/2022] Open
Abstract
Background Blood flow is essential in maintaining tissue health. Thus, compromised blood flow can prevent tissue healing. An adducted hallux, as seen inside a narrow shoe, may put passive tension on the abductor hallucis, compressing the lateral plantar artery into the calcaneus and restricting blood flow. The purposes of this study were to compare lateral plantar artery blood flow before and after passive hallux adduction and to compare blood flow with arch height. Methods Forty-five healthy volunteers (20 female, 25 male; age = 24.8 ± 6.8 yr; height = 1.7 ± 0.1 m; weight = 73.4 ± 13.5 kg) participated in this cross-over design study. Arch height index (AHI) was calculated, and blood flow measurements were obtained using ultrasound (L8-18i transducer, GE Logiq S8). The lateral plantar artery was imaged deep to abductor hallucis for 120 s: 60 s at rest, then 60 s of passive hallux adduction. Maximal passive hallux adduction was performed by applying pressure to the medial side of the hallux. Blood flow was calculated in mL/min, and pre-passive hallux adduction was compared to blood flow during passive hallux adduction. Results Log transformed data was used to run a paired t-test between the preadduction and postadduction blood flow. The volume of blood flow was 22.2% lower after passive hallux adduction compared to before (- 0.250 ± 0.063, p < 0.001). As AHI decreased, there was a greater negative change in blood flow. As baseline blood flow increased, there was also a greater negative change in blood flow. Conclusions Our preliminary findings of decreased blood flow through passive hallux adduction indicate conditions that elicit passive hallux adduction (e.g. wearing narrow-toed shoes) may have important effects on foot blood flow. Individuals with lower AHI appear to have a greater risk of decreased blood flow with passive hallux adduction.
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Affiliation(s)
- Julia L Jacobs
- 1Department of Exercise Sciences, Brigham Young University, 106 Smith Fieldhouse, Provo, UT 84602 USA
| | - Sarah T Ridge
- 1Department of Exercise Sciences, Brigham Young University, 106 Smith Fieldhouse, Provo, UT 84602 USA
| | - Dustin A Bruening
- 1Department of Exercise Sciences, Brigham Young University, 106 Smith Fieldhouse, Provo, UT 84602 USA
| | - K Annie Brewerton
- 1Department of Exercise Sciences, Brigham Young University, 106 Smith Fieldhouse, Provo, UT 84602 USA
| | - Jayson R Gifford
- 1Department of Exercise Sciences, Brigham Young University, 106 Smith Fieldhouse, Provo, UT 84602 USA
| | - Daniel M Hoopes
- Revere Health Orthopaedics, 1055 North 500 West #121, Building C, Provo, UT 84604 USA
| | - A Wayne Johnson
- 1Department of Exercise Sciences, Brigham Young University, 106 Smith Fieldhouse, Provo, UT 84602 USA
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Crossley KW, Porter DA, Ellsworth J, Caldwell T, Feland JB, Mitchell U, Johnson AW, Egget D, Gifford JR. Effect of Cuff Pressure on Blood Flow during Blood Flow-restricted Rest and Exercise. Med Sci Sports Exerc 2019; 52:746-753. [PMID: 31568024 DOI: 10.1249/mss.0000000000002156] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
PURPOSE This study investigated the relationship between blood flow restriction (BFR) cuff pressure and blood flow at rest and during exercise, with the aim of determining if lower cuff pressures will provide an ischemic stimulus comparable to higher pressures. METHODS The relationship between blood flow and cuff pressure at rest was determined by measuring blood flow (Doppler Ultrasound) through the superficial femoral artery (SFA) in 23 adults across a range of pressures (0%-100% Arterial Occlusion Pressure at rest [rAOP]). The interplay between cuff pressure, blood flow and exercise was assessed by determining AOP at rest and during plantar flexion exercise (eAOP) and subsequently measuring the blood flow response to plantar flexion exercise with BFR cuff pressure set to either 40% rAOP or 40% eAOP. RESULTS At rest, a nonlinear relationship between cuff pressure and blood flow through the SFA exhibited a plateau at moderate pressures, with nonsignificant differences in blood flow (~9%, P = 1.0) appearing between pressures ranging from 40% to 80% rAOP. While eAOP was greater than rAOP (229 ± 1.5 mm Hg vs 202 ± 1.5 mm Hg, P < 0.01), blood flow during plantar flexion exercise did not significantly differ (P = 0.49) when applying 40% rAOP or 40% eAOP. CONCLUSIONS Blood flow through the SFA exhibits a nonlinear relationship with cuff pressure, such that cuff pressures in the range of 40% to 80% rAOP reduce blood flow to approximately the same degree. The BFR interventions opting for lower (e.g., 40% AOP), more comfortable pressures will likely provide an ischemic stimulus comparable to that of higher (80% AOP), less-comfortable pressures.
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Affiliation(s)
- Kent W Crossley
- Department of Exercise Sciences, Brigham Young University, Provo, UT
| | - Doran A Porter
- Department of Exercise Sciences, Brigham Young University, Provo, UT
| | - Joshua Ellsworth
- Department of Exercise Sciences, Brigham Young University, Provo, UT
| | - Tabitha Caldwell
- Department of Exercise Sciences, Brigham Young University, Provo, UT
| | | | | | | | - Dennis Egget
- Department of Statistics, Brigham Young University, Provo, UT
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Hureau TJ, Weavil JC, Thurston TS, Wan HY, Gifford JR, Jessop JE, Buys MJ, Richardson RS, Amann M. Pharmacological attenuation of group III/IV muscle afferents improves endurance performance when oxygen delivery to locomotor muscles is preserved. J Appl Physiol (1985) 2019; 127:1257-1266. [PMID: 31513446 DOI: 10.1152/japplphysiol.00490.2019] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We sought to investigate the role of group III/IV muscle afferents in limiting endurance exercise performance, independently of their role in optimizing locomotor muscle O2 delivery. While breathing 100% O2 to ensure a similar arterial O2 content ([Formula: see text]) in both trials, eight male cyclists performed 5-km time trials under control conditions (HCTRL) and with lumbar intrathecal fentanyl (HFENT) impairing neural feedback from the lower limbs. After each time trial, common femoral artery blood flow (FBF) was quantified (Doppler ultrasound) during constant-load cycling performed at the average power of the preceding time trial. The assessment of end-tidal gases, hemoglobin content and saturation, and FBF facilitated the calculation of leg O2 delivery. Locomotor muscle activation during cycling was estimated from vastus lateralis EMG. With electrical femoral nerve stimulation, peripheral and central fatigue were quantified by pre- to postexercise decreases in quadriceps twitch torque (ΔQtw) and voluntary activation (ΔVA), respectively. FBF (~16 mL·min-1·W-1; P = 0.6), [Formula: see text] (~24 mL O2/dL; P = 0.9), and leg O2 delivery (~0.38 mL O2·min-1·W-1; P = 0.9) were not different during HCTRL and HFENT. Mean power output and time to completion were significantly improved by 9% (~310 W vs. ~288 W) and 3% (~479 s vs. ~463 s), respectively, during HFENT compared with HCTRL. Quadriceps muscle activation was 9 ± 7% higher during HFENT compared with HCTRL (P < 0.05). ΔQtw was significantly greater in HFENT compared with HCTRL (54 ± 8% vs. 39 ± 9%), whereas ΔVA was not different (~5%; P = 0.3) in both trials. These findings reveal that group III/IV muscle afferent feedback limits whole body endurance exercise performance and peripheral fatigue by restricting neural activation of locomotor muscle.NEW & NOTEWORTHY Group III/IV muscle afferent feedback facilitates endurance performance by optimizing locomotor muscle O2 delivery but also limits performance by restricting neural drive to locomotor muscle. To isolate the performance-limiting effect of these sensory neurons, we pharmacologically attenuated their central projection during a cycling time trial while controlling for locomotor muscle O2 delivery. With no difference in leg O2 delivery, afferent blockade attenuated the centrally mediated restriction in motoneuronal output and improved cycling performance.
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Affiliation(s)
- Thomas J Hureau
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Medicine and EA 3072: Mitochondria, Oxidative Stress and Muscular Protection Laboratory, University of Strasbourg, Strasbourg, France
| | - Joshua C Weavil
- Geriatric Research, Education, and Clinical Center, Salt Lake City Department of Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Taylor S Thurston
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Hsuan-Yu Wan
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Jayson R Gifford
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Jacob E Jessop
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Michael J Buys
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Russell S Richardson
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Salt Lake City Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Markus Amann
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Salt Lake City Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah.,Department of Anesthesiology, University of Utah, Salt Lake City, Utah
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Ratchford SM, Clifton HL, Gifford JR, LaSalle DT, Thurston TS, Bunsawat K, Alpenglow JK, Richardson RS, Wright JB, Ryan JJ, Wray DW. Impact of acute antioxidant administration on inflammation and vascular function in heart failure with preserved ejection fraction. Am J Physiol Regul Integr Comp Physiol 2019; 317:R607-R614. [PMID: 31483155 DOI: 10.1152/ajpregu.00184.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Although it is now well established that heart failure with preserved ejection fraction (HFpEF) is associated with marked inflammation and a prooxidant state that is accompanied by vascular dysfunction, whether acute antioxidant (AO) administration can effectively target these disease-related decrements has not been evaluated. Thus, the present study sought to evaluate the efficacy of an acute over-the-counter AO cocktail (600 mg α-lipoic acid, 1,000 mg vitamin C, and 600 IU vitamin E) to mitigate inflammation and oxidative stress, and subsequently improve nitric oxide (NO) bioavailability and vascular function, in patients with HFpEF. Flow-mediated dilation (FMD) and reactive hyperemia (RH) were evaluated to assess conduit vessel and microvascular function, respectively, 90 min after administration of either placebo (PL) or AO in 16 patients with HFpEF (73 ± 10 yr, EF 54-70%) using a double-blind, crossover design. Circulating biomarkers of inflammation (C-reactive protein, CRP), oxidative stress (malondialdehyde and protein carbonyl), free radical concentration (EPR spectroscopy), antioxidant capacity, ascorbate and NO bioavailability (plasma nitrate, [Formula: see text], and nitrite, [Formula: see text]) were also assessed. FMD improved following AO administration (PL: 3.49 ± 0.7%, AO: 5.83 ± 1.0%), whereas RH responses were similar between conditions (PL: 428 ± 51 mL, AO: 425 ± 51 mL). AO administration decreased CRP (PL: 4,429 ± 705 ng/mL, AO: 3,664 ± 520 ng/mL) and increased ascorbate (PL: 30.0 ± 2.9 µg/mL, AO: 45.1 ± 3.7 µg/mL) and [Formula: see text] (PL: 182 ± 21 nM, AO: 213 ± 24 nM) but did not affect other biomarkers. Together, these data suggest that acute AO administration can exert anti-inflammatory effects and improve conduit artery vasodilation, but not microvascular function, in patients with HFpEF.
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Affiliation(s)
- Stephen M Ratchford
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
| | - Heather L Clifton
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
| | - Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, Utah
| | - D Taylor LaSalle
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Taylor S Thurston
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Kanokwan Bunsawat
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
| | - Jeremy K Alpenglow
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Josephine B Wright
- Department of Internal Medicine, Division of Cardiovascular Medicine, University of Utah, Salt Lake City, Utah
| | - John J Ryan
- Department of Internal Medicine, Division of Cardiovascular Medicine, University of Utah, Salt Lake City, Utah
| | - D Walter Wray
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
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40
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Layec G, Blain GM, Rossman MJ, Park SY, Hart CR, Trinity JD, Gifford JR, Sidhu SK, Weavil JC, Hureau TJ, Amann M, Richardson RS. Acute High-Intensity Exercise Impairs Skeletal Muscle Respiratory Capacity. Med Sci Sports Exerc 2019; 50:2409-2417. [PMID: 30102675 DOI: 10.1249/mss.0000000000001735] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
PURPOSE The effect of an acute bout of exercise, especially high-intensity exercise, on the function of mitochondrial respiratory complexes is not well understood, with potential implications for both the healthy population and patients undergoing exercise-based rehabilitation. Therefore, this study sought to comprehensively examine respiratory flux through the different complexes of the electron transport chain in skeletal muscle mitochondria before and immediately after high-intensity aerobic exercise. METHODS Muscle biopsies of the vastus lateralis were obtained at baseline and immediately after a 5-km time trial performed on a cycle ergometer. Mitochondrial respiratory flux through the complexes of the electron transport chain was measured in permeabilized skeletal muscle fibers by high-resolution respirometry. RESULTS Complex I + II state 3 (state 3CI + CII) respiration, a measure of oxidative phosphorylation capacity, was diminished immediately after the exercise (pre, 27 ± 3 ρm·mg·s; post, 17 ± 2 ρm·mg·s; P < 0.05). This decreased oxidative phosphorylation capacity was predominantly the consequence of attenuated complex II-driven state 3 (state 3CII) respiration (pre, 17 ± 1 ρm·mg·s; post, 9 ± 2 ρm·mg·s; P < 0.05). Although complex I-driven state 3 (3CI) respiration was also lower (pre, 20 ± 2 ρm·mg·s; post, 14 ± 4 ρm·mg·s), this did not reach statistical significance (P = 0.27). In contrast, citrate synthase activity, proton leak (state 2 respiration), and complex IV capacity were not significantly altered immediately after the exercise. CONCLUSIONS These findings reveal that acute high-intensity aerobic exercise significantly inhibits skeletal muscle state 3CII and oxidative phosphorylation capacity. This, likely transient, mitochondrial defect might amplify the exercise-induced development of fatigue and play an important role in initiating exercise-induced mitochondrial adaptations.
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Affiliation(s)
- Gwenael Layec
- Department of Medicine, University of Utah, Salt Lake City, UT.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT.,Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT
| | | | - Matthew J Rossman
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT
| | - Song Y Park
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT
| | - Corey R Hart
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT
| | - Joel D Trinity
- Department of Medicine, University of Utah, Salt Lake City, UT.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT.,Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT
| | - Jayson R Gifford
- Department of Medicine, University of Utah, Salt Lake City, UT.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT.,Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT
| | - Simranjit K Sidhu
- Department of Medicine, University of Utah, Salt Lake City, UT.,Discipline of Physiology, Adelaide Medical School, The University of Adelaide, Adelaide, AUSTRALIA
| | - Joshua C Weavil
- Department of Medicine, University of Utah, Salt Lake City, UT
| | - Thomas J Hureau
- Department of Medicine, University of Utah, Salt Lake City, UT.,Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT.,Mitochondria, Oxidative Stress and Muscular Protection Laboratory, EA 3072, University of Strasbourg, Strasbourg, FRANCE
| | - Markus Amann
- Department of Medicine, University of Utah, Salt Lake City, UT.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT.,Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT
| | - Russell S Richardson
- Department of Medicine, University of Utah, Salt Lake City, UT.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT.,Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT
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Gifford JR, Garten R, Weavil J, Broxterman R, Trinity J, Richardson R. Looking Beyond A-vo2 Difference: Peripheral Adaptations And Vo2Max In Trained And Untrained Adults. Med Sci Sports Exerc 2019. [DOI: 10.1249/01.mss.0000560495.44479.62] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Jarrett CL, Shields KL, Broxterman RM, Park SH, Gifford JR, Richardson RS. Imaging Transcranial Doppler: A Novel Approach to Assess Cerebral Blood Flow. Med Sci Sports Exerc 2019. [DOI: 10.1249/01.mss.0000560893.82220.54] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Broxterman RM, Witman MA, Trinity JD, Groot HJ, Rossman MJ, Park SY, Malenfant S, Gifford JR, Kwon OS, Park SH, Jarrett CL, Shields KL, Hydren JR, Bisconti AV, Owan T, Abraham A, Tandar A, Lui CY, Smith BR, Richardson RS. Strong Relationship Between Vascular Function in the Coronary and Brachial Arteries. Hypertension 2019; 74:208-215. [PMID: 31055952 DOI: 10.1161/hypertensionaha.119.12881] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Early detection of coronary artery dysfunction is of paramount cardiovascular clinical importance, but a noninvasive assessment is lacking. Indeed, the brachial artery flow-mediated dilation test only weakly correlated with acetylcholine-induced coronary artery function ( r=0.36). However, brachial artery flow-mediated dilation methodologies have, over time, substantially improved. This study sought to determine if updates to this technique have improved the relationship with coronary artery function and the noninvasive indication of coronary artery dysfunction. Coronary artery and brachial artery function were assessed in 28 patients referred for cardiac catheterization (61±11 years). Coronary artery function was determined by the change in artery diameter with a 1.82 μg/min intracoronary acetylcholine infusion. Based on the change in vessel diameter, patients were characterized as having dysfunctional coronary arteries (>5% vasoconstriction) or relatively functional coronary arteries (<5% vasoconstriction). Brachial artery function was determined by flow-mediated dilation, adhering to current guidelines. The acetylcholine-induced change in vessel diameter was smaller in patients with dysfunctional compared with relatively functional coronary arteries (-11.8±4.6% versus 5.8±9.8%, P<0.001). Consistent with this, brachial artery flow-mediated dilation was attenuated in patients with dysfunctional compared with relatively functional coronaries (2.9±1.9% versus 6.2±4.2%, P=0.007). Brachial artery flow-mediated dilation was strongly correlated with the acetylcholine-induced change in coronary artery diameter ( r=0.77, P<0.0001) and was a strong indicator of coronary artery dysfunction (receiver operator characteristic=78%). The current data support that updates to the brachial artery flow-mediated dilation technique have strengthened the relationship with coronary artery function, which may now provide a clinically meaningful indication of coronary artery dysfunction.
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Affiliation(s)
- Ryan M Broxterman
- From the Department of Internal Medicine (R.M.B., J.D.T., S.M., C.L.J., T.O., A.A., A.T., C.Y.L., B.R.S., R.S.R.), University of Utah, Salt Lake City.,Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC (R.M.B., J.D.T., C.L.J., R.S.R.)
| | - Melissa A Witman
- Kinesiology and Applied Physiology, University of Delaware, Newark (M.A.W.)
| | - Joel D Trinity
- From the Department of Internal Medicine (R.M.B., J.D.T., S.M., C.L.J., T.O., A.A., A.T., C.Y.L., B.R.S., R.S.R.), University of Utah, Salt Lake City.,Department of Nutrition and Integrative Physiology (J.D.T., S.H.P., K.L.S., J.R.H., R.S.R.), University of Utah, Salt Lake City.,Center on Aging (J.D.T., R.S.R.), University of Utah, Salt Lake City.,Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC (R.M.B., J.D.T., C.L.J., R.S.R.)
| | - H Jonathan Groot
- Health-Kinesiology-Recreation (H.J.G.), University of Utah, Salt Lake City
| | | | - Song-Young Park
- School of Health and Kinesiology, University of Nebraska Omaha (S.-Y.P.)
| | - Simon Malenfant
- From the Department of Internal Medicine (R.M.B., J.D.T., S.M., C.L.J., T.O., A.A., A.T., C.Y.L., B.R.S., R.S.R.), University of Utah, Salt Lake City
| | - Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, UT (J.R.G.)
| | - Oh Sung Kwon
- Department of Kinesiology, University of Connecticut, Storrs (O.S.K.)
| | - Soung Hun Park
- Department of Nutrition and Integrative Physiology (J.D.T., S.H.P., K.L.S., J.R.H., R.S.R.), University of Utah, Salt Lake City
| | - Catherine L Jarrett
- From the Department of Internal Medicine (R.M.B., J.D.T., S.M., C.L.J., T.O., A.A., A.T., C.Y.L., B.R.S., R.S.R.), University of Utah, Salt Lake City.,Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC (R.M.B., J.D.T., C.L.J., R.S.R.)
| | - Katherine L Shields
- Department of Nutrition and Integrative Physiology (J.D.T., S.H.P., K.L.S., J.R.H., R.S.R.), University of Utah, Salt Lake City
| | - Jay R Hydren
- Department of Nutrition and Integrative Physiology (J.D.T., S.H.P., K.L.S., J.R.H., R.S.R.), University of Utah, Salt Lake City
| | - Angela V Bisconti
- Department of Biomedical Sciences for Health, University of Milano, Italy (A.V.B.)
| | - Theophilus Owan
- From the Department of Internal Medicine (R.M.B., J.D.T., S.M., C.L.J., T.O., A.A., A.T., C.Y.L., B.R.S., R.S.R.), University of Utah, Salt Lake City
| | - Anu Abraham
- From the Department of Internal Medicine (R.M.B., J.D.T., S.M., C.L.J., T.O., A.A., A.T., C.Y.L., B.R.S., R.S.R.), University of Utah, Salt Lake City
| | - Anwar Tandar
- From the Department of Internal Medicine (R.M.B., J.D.T., S.M., C.L.J., T.O., A.A., A.T., C.Y.L., B.R.S., R.S.R.), University of Utah, Salt Lake City
| | - Charles Y Lui
- From the Department of Internal Medicine (R.M.B., J.D.T., S.M., C.L.J., T.O., A.A., A.T., C.Y.L., B.R.S., R.S.R.), University of Utah, Salt Lake City
| | - Brigham R Smith
- From the Department of Internal Medicine (R.M.B., J.D.T., S.M., C.L.J., T.O., A.A., A.T., C.Y.L., B.R.S., R.S.R.), University of Utah, Salt Lake City
| | - Russell S Richardson
- From the Department of Internal Medicine (R.M.B., J.D.T., S.M., C.L.J., T.O., A.A., A.T., C.Y.L., B.R.S., R.S.R.), University of Utah, Salt Lake City.,Department of Nutrition and Integrative Physiology (J.D.T., S.H.P., K.L.S., J.R.H., R.S.R.), University of Utah, Salt Lake City.,Center on Aging (J.D.T., R.S.R.), University of Utah, Salt Lake City.,Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC (R.M.B., J.D.T., C.L.J., R.S.R.)
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Hydren JR, Broxterman RM, Trinity JD, Gifford JR, Kwon OS, Kithas AC, Richardson RS. Delineating the age-related attenuation of vascular function: Evidence supporting the efficacy of the single passive leg movement as a screening tool. J Appl Physiol (1985) 2019; 126:1525-1532. [PMID: 30946637 DOI: 10.1152/japplphysiol.01084.2018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Continuous passive leg movement (PLM) is a promising clinical assessment of the age-related decline in peripheral vascular function. To further refine PLM, this study evaluated the efficacy of a single PLM (sPLM), a simplified variant of the more established continuous movement approach, to delineate between healthy young and old men based on vascular function. Twelve young (26 ± 5 yr) and 12 old (70 ± 7 yr) subjects underwent sPLM (a single passive flexion and extension of the knee joint through 90°), with leg blood flow (LBF, common femoral artery with Doppler ultrasound), blood pressure (finger photoplethysmography), and leg vascular conductance (LVC) assessed. A receiver operator characteristic curve analysis was used to determine an age-specific cut score, and a factor analysis was performed to assess covariance. Baseline LBF and LVC were not different between groups (P = 0.6). The high level of covariance and similar predictive value for all PLM-induced LBF and LVC responses indicates LBF, alone, can act as a surrogate variable in this paradigm. The peak sPLM-induced increase in LBF from baseline was attenuated in the old (Young: 717 ± 227, Old: 260 ± 97 ml/min, P < 0.001; cut score: 372 ml/min), as was the total LBF response (Young: 155 ± 67, Old: 26 ± 17 ml, P < 0.001; cut score: 58 ml). sPLM, a simplified version of PLM, exhibits the prerequisite qualities of a valid screening test for peripheral vascular dysfunction, as evidenced by an age-related attenuation in the peripheral hyperemic response and a clearly delineated age-specific cut score. NEW & NOTEWORTHY Single passive leg movement (sPLM) exhibits the prerequisite qualities of a valid screening test for peripheral vascular dysfunction. sPLM displayed an age-related reduction in the peripheral hemodynamic response for amplitude, duration, initial rate of change, and total change with clearly delineated age-specific cut scores. sPLM has a strong candidate variable that is a simple single numeric value, for which to appraise peripheral vascular function, the 45-s hyperemic response (leg blood flow area under the curve: 45 s).
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Affiliation(s)
- Jay R Hydren
- Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
| | - Ryan M Broxterman
- Geriatric Research, Education, and Clinical Center, Salt Lake City Veteran Affairs Medical Center , Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Joel D Trinity
- Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Salt Lake City Veteran Affairs Medical Center , Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Jayson R Gifford
- Department of Internal Medicine, University of Utah , Salt Lake City, Utah.,Department of Exercise Sciences, Brigham Young University, Utah
| | - Oh Sung Kwon
- Department of Internal Medicine, University of Utah , Salt Lake City, Utah.,Department of Kinesiology, University of Connecticut , Storrs, Connecticut
| | - Andrew C Kithas
- Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Russell S Richardson
- Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Salt Lake City Veteran Affairs Medical Center , Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah
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Kwon OS, Layec G, Broxterman RM, Gifford JR, Park SH, Shields KL, Richardson RS. Vascular Dysfunction in Chronic Obstructive Pulmonary Disease (COPD): The Role of Mitochondrial‐derived Oxidative Stress. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.527.10] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Oh Sung Kwon
- KinesiologyUniversity of ConnecticutStorrsCT
- Internal MedicineUniversity of UtahSalt Lake CityUT
| | - Gwenael Layec
- KinesiologyUniversity of Massachusetts AmherstAmherstMA
| | | | | | - Soung Hun Park
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | | | - Russell S Richardson
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
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46
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Hydren JR, Gifford JR, Jarrett CL, Park SH, Shields KL, Ratchford SM, Broxterman RM, Kithas AC, Thurston TS, Selzman CH, Drakos SG, Richardson RS. Vascular Function in Heart Failure Patients Implanted with a Continuous‐Flow Left Ventricular Assist Device: Impact of Increasing Peripheral Vascular Pulsatility. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.532.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jay R. Hydren
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Jayson R. Gifford
- Geriatric Research, Education, and Clinical CenterSalt Lake City VA Medical CenterSalt Lake CityUT
| | - Catherine L. Jarrett
- Geriatric Research, Education, and Clinical CenterSalt Lake City VA Medical CenterSalt Lake CityUT
| | - Soung Hun Park
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Katherine L. Shields
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Stephen M. Ratchford
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VA Medical CenterSalt Lake CityUT
| | - Ryan M. Broxterman
- Geriatric Research, Education, and Clinical CenterSalt Lake City VA Medical CenterSalt Lake CityUT
| | - Andrew C. Kithas
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | - Taylor S. Thurston
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | | | - Stavros G. Drakos
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VA Medical CenterSalt Lake CityUT
| | - Russell S. Richardson
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VA Medical CenterSalt Lake CityUT
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47
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Craig JC, Broxterman RM, La Salle DT, Cerbie J, Ratchford SM, Gifford JR, Bunsawat K, Nelson AD, Bledsoe AD, Morgan DE, Wray DW, Richardson RS, Trinity JD. The Role of Endothelin‐1 in Exercising Blood Flow and Blood Pressure Regulation in Patients with Hypertension. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.696.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Ryan M Broxterman
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
| | - D Taylor La Salle
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - James Cerbie
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Stephen M Ratchford
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
| | - Jayson R Gifford
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
| | | | | | | | | | - D Walter Wray
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
| | - Russell S Richardson
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
| | - Joel D Trinity
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
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Hart CR, Layec G, Trinity JD, Le Fur Y, Gifford JR, Clifton HL, Richardson RS. Oxygen availability and skeletal muscle oxidative capacity in patients with peripheral artery disease: implications from in vivo and in vitro assessments. Am J Physiol Heart Circ Physiol 2018; 315:H897-H909. [PMID: 29932772 DOI: 10.1152/ajpheart.00641.2017] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Evidence suggests that the peak skeletal muscle mitochondrial ATP synthesis rate ( Vmax) in patients with peripheral artery disease (PAD) may be attenuated due to disease-related impairments in O2 supply. However, in vitro assessments suggest intrinsic deficits in mitochondrial respiration despite ample O2 availability. To address this conundrum, Doppler ultrasound, near-infrared spectroscopy, phosphorus magnetic resonance spectroscopy, and high-resolution respirometry were combined to assess convective O2 delivery, tissue oxygenation, Vmax, and skeletal muscle mitochondrial capacity (complex I + II, state 3 respiration), respectively, in the gastrocnemius muscle of 10 patients with early stage PAD and 11 physical activity-matched healthy control (HC) subjects. All participants were studied in free-flow control conditions (FF) and with reactive hyperemia (RH) induced by a period of brief ischemia during the last 30 s of submaximal plantar flexion exercise. Patients with PAD repeated the FF and RH trials under hyperoxic conditions (FF + 100% O2 and RH + 100% O2). Compared with HC subjects, patients with PAD exhibited attenuated O2 delivery at the same absolute work rate and attenuated tissue reoxygenation and Vmax after relative intensity-matched exercise. Compared with the FF condition, only RH + 100% O2 significantly increased convective O2 delivery (~44%), tissue reoxygenation (~54%), and Vmax (~60%) in patients with PAD ( P < 0.05), such that Vmax was now not different from HC subjects. Furthermore, there was no evidence of an intrinsic mitochondrial deficit in PAD, as assessed in vitro with adequate O2. Thus, in combination, this comprehensive in vivo and in vitro investigation implicates O2 supply as the predominant factor limiting mitochondrial oxidative capacity in early stage PAD. NEW & NOTEWORTHY Currently, there is little accord as to the role of O2 availability and mitochondrial function in the skeletal muscle dysfunction associated with peripheral artery disease. This is the first study to comprehensively use both in vivo and in vitro approaches to document that the skeletal muscle dysfunction associated with early stage peripheral artery disease is predominantly a consequence of limited O2 supply and not the impact of an intrinsic mitochondrial defect in this pathology.
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Affiliation(s)
- Corey R Hart
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Exercise and Sport Science, University of Utah , Salt Lake City, Utah
| | - Gwenael Layec
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Medicine, Division of Geriatrics, University of Utah , Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
| | - Joel D Trinity
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Medicine, Division of Geriatrics, University of Utah , Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
| | - Yann Le Fur
- Centre de Résonance Magnétique Biologique et Médicale Unité Mixte de Recherché 7339, Aix-Marseille Université, Centre National de la Recherche Scientifique, Marseille , France
| | - Jayson R Gifford
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center , Salt Lake City, Utah
| | - Heather L Clifton
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Medicine, Division of Geriatrics, University of Utah , Salt Lake City, Utah
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Medicine, Division of Geriatrics, University of Utah , Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
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Hart CR, Layec G, Trinity JD, Kwon OS, Zhao J, Reese VR, Gifford JR, Richardson RS. Increased skeletal muscle mitochondrial free radical production in peripheral arterial disease despite preserved mitochondrial respiratory capacity. Exp Physiol 2018; 103:838-850. [PMID: 29604234 DOI: 10.1113/ep086905] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 03/23/2018] [Indexed: 12/17/2022]
Abstract
NEW FINDINGS What is the central question of this study? What is the degree to which skeletal muscle mitochondria-derived reactive oxygen species (ROS) production is linked to impaired skeletal muscle function in patients with early-stage peripheral arterial disease (PAD) and what is the impact on mitochondrial respiratory capacity? What is the main finding and its importance? This is the first study to document increased mitochondria-derived reactive oxygen species production associated with elevated intramuscular oxidative stress, despite preserved mitochondrial respiratory function, in patients with PAD. Furthermore, systemic inflammation, mitochondria-derived ROS production and skeletal muscle oxidative stress were strongly correlated to disease severity, as indicated by ankle-brachial index, in patients with PAD. ABSTRACT Skeletal muscle mitochondrial dysfunction, which is not fully explained by disease-related arterial occlusion, has been implicated in the pathophysiology of peripheral arterial disease (PAD). Therefore, this study comprehensively assessed mitochondrial respiratory function in biopsies from the gastrocnemius of 10 patients with PAD (Fontaine Stage II) and 12 healthy controls (HC). Intramuscular and systemic inflammation, mitochondria-derived reactive oxygen species (ROS) production, and oxidative stress were also assessed to better understand the mechanisms responsible for the proposed PAD-induced mitochondrial dysfunction. Interestingly, mitochondrial respiratory capacity, assessed as complex I (CI) and complex II (CII)-driven State 3 respiration, measured separately and in combination (State 3 CI+II), revealed no difference between the patients with PAD and the HC. However, mitochondria-derived ROS production was significantly elevated in PAD (HC: 1.0 ± 0.9; PAD: 4.3 ± 1.0 AU (mg tissue)-1 ). Furthermore, patients with PAD exhibited significantly greater concentrations of the pro-inflammatory markers tumour necrosis factor α in plasma (HC: 0.9 ± 0.4; PAD: 2.0 ± 0.3 pg ml-1 ) and interleukin 6 in both plasma (HC: 2.3 ± 0.4; PAD: 4.3 ± 0.5 pg ml-1 ) and muscle (∼75% greater). Intramuscular oxidative stress, assessed by protein carbonyls and 4-hydroxynonenal, was significantly greater in PAD compared to HC. Ankle brachial index was significantly correlated with intramuscular inflammation, oxidative stress and mitochondria-derived ROS production. Thus, elevated intramuscular inflammation, oxidative stress and mitochondria-derived ROS production are likely to contribute to the pathophysiology of the skeletal muscle dysfunction associated with PAD, even in the presence of preserved mitochondrial respiratory function in this population.
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Affiliation(s)
- Corey R Hart
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA
| | - Gwenael Layec
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA.,Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA
| | - Joel D Trinity
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA.,Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA
| | - Oh Sung Kwon
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA.,Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA
| | - Jia Zhao
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA
| | - Van R Reese
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA
| | - Jayson R Gifford
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA.,Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT, USA.,Department of Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
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50
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Gifford JR, Mangum T, Weavil J, Nelson A, Lee JF, Groot HJ, Broxterman R, Rossman M, Richardson R. Particulate Matter Air Pollution and Vascular Function in Older Adults. Med Sci Sports Exerc 2018. [DOI: 10.1249/01.mss.0000535555.94576.c6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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