Journal of applied physiology最新文献

{"title":"Modulation of Motor Unit Recruitment Threshold and Common Synaptic Inputs in Triceps Surae Muscles: Effects of Ankle Position.","authors":"Xin Sienna Yu, Jackson T Levine, José L Pons","doi":"10.1152/japplphysiol.00029.2025","DOIUrl":"https://doi.org/10.1152/japplphysiol.00029.2025","url":null,"abstract":"<p><p>The objective of this study was to investigate how altering muscle length by changing ankle position affects force control, motor unit recruitment threshold, and motor unit coherence within and across triceps surae muscles. Sixteen healthy young adults performed isometric plantarflexion (PF) at three ankle positions with the ankle plantarflexed at 20° (PF20°), at the neural position (PF0°) and dorsiflexed at 20° (DF20°). High-density surface electromyography was used to record the medial and lateral heads of the gastrocnemius muscle (GM and GL), and the medial and lateral portions of the soleus muscle (SL and SM). Motor unit cumulative spike trains (MUCST) were used to calculate intramuscular, intermuscular, and Force-MUCST coherence in the delta (0-5 Hz), alpha (5-15 Hz), and beta (15-35 Hz) frequency bands. Recruitment thresholds of motor units matched across positions decreased when shifting the ankle from a shortened to lengthened position in GM, SL, and SM, while remaining unchanged and highest in GL. This change in ankle position also led to increased GM-SM coherence and intramuscular coherence in SM and SL in the delta band, and improvements in force steadiness. In contrast, alpha band intramuscular coherence and Force-MUCST coherence decreased. Minimal changes were observed in beta band coherence across positions. This study reveals a neuromuscular control strategy that modulates motor unit recruitment and common synaptic inputs of triceps surae to maintain force output during isometric plantarflexions at varying muscle lengths.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144149452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A data-driven model to estimate breathing-induced intra-trunk blood shifts during exercise.","authors":"Gabriele Corigliano, Barbara Uva, Bengt Kayser, Andrea Aliverti, Frédéric Stucky","doi":"10.1152/japplphysiol.00749.2024","DOIUrl":"https://doi.org/10.1152/japplphysiol.00749.2024","url":null,"abstract":"<p><p>The pressure swings generated by the respiratory muscles induce blood shifts (Vbs) between the trunk and the extremities. Vbs varies with swing amplitude and breathing pattern and can reach sizable volumes. While Vbs was successfully explored using double-body plethysmography the extent of intra-trunk blood shifting (between abdomen and thorax, Vbs_IT) remains to be quantified. We here present an electrical model of the cardiovascular system which allows to derive quantitative estimates of breath-by-breath Vbs_IT. We first validated the model with experimental data collected from healthy participants performing exercise with various breathing patterns including spontaneous (CTRL), abdominal (AB) and rib cage breathing (RC), and with external expiratory flow limitation (EFLe). We then fed the model with other experimental data to derive Vbs_IT in a proof-of-concept fashion. Breath-by-breath fluctuations in Vbs derived from the model matched experimental data. Computations of Vbs_IT were in line with expectations, showing small fluctuations with spontaneous breathing and substantial increases during AB, RC and EFLe. Intra-breath Vbs_IT showed a close relationship with intra-breath transdiaphragmatic pressure during inspiration in all conditions, and during expiration in AB and RC, reflecting the net effect of hydraulic pressure fluctuations on blood displacement between the two compartments. This model may benefit further work investigating (patho)physiological mechanisms of various conditions affecting cardiorespiratory function, both at rest and during exercise.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144150562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pulmonary adaptations to 12 weeks of supervised high intensity interval training in COPD: A non-randomized controlled pilot study.","authors":"Jacob Peter Hartmann, Stine Buus Nymand, Helene Louise Hartmeyer, Amalie Bach Andersen, Milan Mohammad, Cody Garett Durrer, Iben Elmerdahl Rasmussen, Camilla Koch Ryrsø, Rie Skovly Thomsen, Sofie Lindskov Hansen, Felix Christoph Müller, Michael Perch, Thomas Kromann Lund, Kristine Jensen, Torgny Wilcke, Susan Al-Atabi, Birgitte Hanel, Regitse Højgaard Christensen, Ulrik Winning Iepsen, Jann Mortensen, Ronan M G Berg","doi":"10.1152/japplphysiol.00037.2025","DOIUrl":"https://doi.org/10.1152/japplphysiol.00037.2025","url":null,"abstract":"<p><p><i>Objective.</i> To investigate the change in diffusing capacity from rest to submaximal exercise in patients with mild to severe COPD compared to a healthy, age- and sex matched control group, and to investigate if the diffusing capacity can be altered by high-intensity interval training (HIIT). <i>Methods.</i> 35 patients with COPD and 15 healthy age- and sex matched controls were included. Pulmonary diffusing capacity was measured using the combined single-breath method using carbon monoxide and nitric oxide (D_L,CO,NO), which were measured at rest and during 60% of peak workload (W_Lpeak) to estimate the alveolar-capillary reserve (change from rest to exercise). A subgroup of 12 patients with COPD and 12 control participants completed a 12-week supervised HIIT intervention with measurements of D_L,CO,NO, computed tomography-based lung tissue mass, and single-photon emission computed tomography to assess the pulmonary perfusion distribution pre and post the HIIT intervention. <i>Results.</i> The alveolar-capillary reserve was reduced in COPD patients in a severity-dependent manner compared to the healthy control group and this was unaltered following the HIIT intervention, despite an increase in exercise capacity. HIIT did not increase lung tissue mass, nor did it improve the pulmonary perfusion distribution during exercise in either group. <i>Conclusion:</i> Alveolar-capillary reserve is reduced in a severity-dependent manner in COPD, and a 12-week supervised HIIT intervention did not induce any changes in either the alveolar-capillary reserve or lung tissue mass, suggesting that the concomitant increase in exercise capacity is likely due to extrapulmonary adaptations.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144136282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural and Functional Characteristics of Healthy and Injured Porcine Lungs During Deflation: A Quantitative CT Imaging Analysis.","authors":"Emmanuel A Akor, Jian Gao, Junfeng Guo, Bing Han, Andrea F Cruz, Jacob Herrmann, Sarah E Gerard, Monica L Hawley, Gary E Christensen, Joseph M Reinhardt, Eric A Hoffman, David W Kaczka","doi":"10.1152/japplphysiol.00443.2024","DOIUrl":"https://doi.org/10.1152/japplphysiol.00443.2024","url":null,"abstract":"<p><p>The acute respiratory distress syndrome (ARDS) is characterized by pathologic and heterogeneous alterations in the mechanical properties of lung tissue. While several techniques exist that allow for assessment of global lung mechanics in health and disease, few techniques allow for quantitative assessment of regional mechanics, which is important for understanding the impact of therapeutic interventions on local structure-function relationships. X-ray computed tomography (CT) is a widely available imaging modality for assessment of regional lung structure, given its high spatial resolution, as well as its ability to provide detailed information on regional anatomic and pathologic features. Quantitative computed tomography (qCT) has evolved into an important tool for assessment of regional and global mechanical changes associated with deranged structure-function relationships in many lung diseases, especially ARDS. The purpose of this study was to determine how specific structural and functional characteristics of the acutely injured lung may be altered, as assessed with various qCT imaging metrics. Such alterations may serve as a template for characterizing the severity of ARDS in patients. We evaluated and compared pressure-volume relationships, distensibility, aeration, tissue texture, and parenchymal deformation in healthy and injured lungs of anesthetized pigs, using volumetric CT images obtained during static breath holds from 30 to 0 cmH₂O airway pressure. We demonstrate how qCT imaging provides unique insight into structure-function changes associated with acute lung injury, and how such techniques may enhance our understanding of regional and global parenchymal mechanics in patients with ARDS or other forms of lung injury.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144136285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combination of running and energy restriction impairs bone parameters but does not inhibit endurance adaptations in fast-twitch muscle in young female rats.","authors":"Yuki Aikawa, Yusuke Wakasugi, Tomoya Fukuyasu, Nobuaki Sasai, Takenori Yamashita, Makoto Ohtsuki, Amane Hori, Kazuki Kioka, Naomi Omi, Naoya Nakai, Kazuhiko Higashida","doi":"10.1152/japplphysiol.00978.2024","DOIUrl":"https://doi.org/10.1152/japplphysiol.00978.2024","url":null,"abstract":"<p><p>Low energy availability refers to a state where the body cannot provide sufficient energy to maintain essential physiological functions due to excessive exercise and inadequate energy intake. In athletes, low energy availability impairs bone parameters but may assist muscle adaptation from endurance training. This study was conducted to explore the effect of the combination of running and energy restriction (ER) on bone parameters and muscular endurance adaptations in young female rats. Seven-weeks-old female rats were divided into four groups: sedentary and <i>ad libitum</i> feeding (AL); voluntary wheel running and AL; sedentary and ER; and voluntary wheel running and ER. The experimental period was 11.5 weeks. The ER groups were fed a 28% restricted diet compared with the sedentary and AL group. Our results demonstrated that the combination of running and ER decreased the body weight, uterus weight, plantaris and soleus muscle weight, bone mineral density of femur, tibia, and lumbar, and trabecular number of tibia. However, running increased the cross-sectional area (CSA) of type I and IIA fibers and the mitochondrial proteins levels in plantaris muscle under both AL and ER conditions. In the soleus muscle, running exerted no significant main effects on the transition to the myofiber type. ER did not affect the transition to the myofiber type and the mitochondrial protein levels in plantaris and soleus muscles. Our study reveals that the combination of running and ER impairs bone parameters; however, running induces endurance adaptations of plantaris muscle under both AL and ER conditions in young female rats.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144127739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"No effect of either heat therapy or aerobic exercise training on blood pressure in adults with untreated hypertension: a randomized clinical trial.","authors":"Brendan W Kaiser, Lindan N Comrada, Brandon M Gibson, Emma L Reed, Kieran S S Abbotts, Emily A Larson, Madison I Serrano, Karen Wiedenfeld Needham, Christopher L Chapman, John R Halliwill, Christopher T Minson","doi":"10.1152/japplphysiol.00959.2024","DOIUrl":"https://doi.org/10.1152/japplphysiol.00959.2024","url":null,"abstract":"<p><p>Hypertension, a primary and preventable risk factor for cardiovascular and kidney disease, may be ameliorated by non-pharmacological lifestyle interventions such as aerobic exercise and heat therapy. While both interventions have been demonstrated to reduce blood pressure in a variety of populations, there are no studies that have directly compared these methods for lowering blood pressure in adults with untreated hypertension. Forty-one adults (48 [35, 56] y) were randomized to complete either 30 sessions of aerobic exercise training (<i>n=</i>20) or heat therapy (<i>n=</i>21) over 8-10 weeks. Ambulatory and in-clinic blood pressure and markers of cardiorespiratory fitness, arterial stiffness, and renal function were measured at baseline (PRE) and after 30 heat therapy or exercise training sessions (POST). 24-h ambulatory systolic blood pressure was not different following either aerobic exercise (PRE: 139 [134, 144] vs POST: 140 [134, 145] mmHg; <i>p=</i>0.65) or heat therapy (134 [128, 139] vs 134 [128, 139]; <i>p=</i>0.81) nor was 24-h ambulatory diastolic blood pressure after aerobic exercise (PRE: 85 [81, 89] vs POST: 86 [83, 90] mmHg; <i>p=</i>0.28) or heat therapy (81 [78, 85] vs 81 [77, 85]; <i>p=</i>0.44). In-clinic blood pressure was similarly unchanged following both aerobic exercise and heat therapy. These pressure responses, along with arterial stiffness and kidney function biomarkers, did not differ between treatment groups (all <i>p></i>0.05). These data suggest that, during an 8- to 10-week intervention, exercise training and heat therapy have similar and limited impacts on blood pressure, arterial stiffness, and biomarkers of kidney function among adults with untreated hypertension.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144127742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Human skeletal muscle-specific hypertrophy with exercise training and aging: a comprehensive review.","authors":"Caroline S Vincenty, Gilhyeon Yoon, Kaitlyn Rogers, Masatoshi Naruse, Scott Trappe, Todd A Trappe","doi":"10.1152/japplphysiol.00892.2024","DOIUrl":"https://doi.org/10.1152/japplphysiol.00892.2024","url":null,"abstract":"<p><p>Age-related skeletal muscle atrophy is a muscle group-specific process. Therefore, we were interested in understanding exercise-induced hypertrophy across different muscles in older individuals. This review provides a comprehensive summary of the available information on muscle-specific hypertrophy responses to exercise training with aging (≥60y). In total, 6018 peer-reviewed publications were reviewed for inclusion (e.g., supervised resistance (RE) or aerobic (AE) exercise training; MRI, CT, or ultrasound determined muscle size), resulting in 1417 individuals from 68 studies (RE: n=1254; AE: n=163). Data were divided across age (60-69y, 70-79y, 80-89y, ≥90y) and duration (≤9, 10-14, 15-19, 20-24, ≥25wks), with the majority coming from the sexa- and septuagenarians (n=1335, 94%) and 10-14wks of training (n=806, 57%). The number of muscle groups (RE: 7, AE: 8) and subcomponent muscles (RE: 10, AE: 16) were a low representation of the whole-body musculature, with 79% of the data (n=1113) coming from the quadriceps. The 10-14wk responses showed a range of unique muscle-specific hypertrophy and atrophy (RE: 60-69y: 2-14% across six muscles; 70-79y: 1-12% across nine muscles; AE: 70-79y: -6% to +9% across 22 muscles). The large quadriceps-only resistance exercise training dataset (60-79 yrs) showed that no additional hypertrophy was observed with increased training repetitions (i.e., dose), and that men and women elicited an equivalent hypertrophic training response. The optimal exercise training mode(s) and dose(s) for all of the skeletal muscles of sexa-, septa-, octo-, and nonagenarian women and men is far from being elucidated based on the current scientific literature.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144127740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hyperbaric Oxygen Increases Mitochondrial Biogenesis and Function with Oxidative Stress in HL-1 Cardiomyocytes.","authors":"Ha-Yeong Young, Sunchul Lee, Yeo-Eun Choi, Sang-Hoon Nam, Seung-Kuy Cha, Yangsik Jeong, Hyun Kim, Tae-Min Shin, Kyu-Sang Park","doi":"10.1152/japplphysiol.00428.2024","DOIUrl":"https://doi.org/10.1152/japplphysiol.00428.2024","url":null,"abstract":"<p><p>Hyperbaric oxygen (HBO₂) therapy has been used to treat various pathological conditions, including carbon monoxide poisoning and ischemia-reperfusion injury. However, the molecular mechanisms underlying these therapeutic effects remain unclear. We investigated HBO₂-induced changes in mitochondrial function and biogenesis in a clonal cardiomyocyte cell line, HL-1. Cells were exposed to HBO₂ (3 atmospheres, 2218 mmHg O₂, 39 mmHg CO₂) in a cell incubation chamber under controlled temperature and humidity conditions. Levels of reactive oxygen species (ROS), gene transcription and translation, mitochondrial membrane potential (ΔΨm), mitochondrial respiration, cellular ATP content, and spontaneous beating foci of HL-1 cells were measured. Exposure (2 or 6 h) to HBO₂ increased the cytosolic and mitochondrial ROS production, followed by upregulation of stress responses, including growth differentiation factor 15 and fibroblast growth factor 21. HBO₂ augmented antioxidant defence signalling through nuclear factor erythroid-2-related factor 2 and mitochondrial biogenesis through peroxisome proliferator-activated receptor-gamma coactivator-1α. HBO₂ exposure also elevated mitochondrial oxygen consumption, ΔΨm, and ATP production. To assess cardiomyocyte function, live cell imaging was performed, and the findings demonstrated an increase in the number of beating clusters in HL-1 cells following exposure to HBO₂. Notably, in HL-1 cells pre-treated with sublethal doses of mitochondrial electron transport chain inhibitors, further depolarisation of ΔΨm was observed after HBO₂ exposure, implying exacerbation of mitochondrial dysfunction. Collectively, HBO₂-induced oxidative stress enhances mitochondrial biogenesis and function, possibly through a stress-mediated response. However, in the presence of defective mitochondrial function, cells may not be able to overcome the stress caused by HBO₂.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144127741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Normal Variation in Brain Volumetrics, CSF Dynamics, and Ocular Structures from Magnetic Resonance Images of Healthy Participants Over Two Years.","authors":"Katrina J Carter, Steven S Laurie, Katherine G Warthen, Stuart H Sater, Bryn A Martin, Ching Mei Feng, Millennia Young, Khader M Hasan, Larry A Kramer, Brandon R Macias","doi":"10.1152/japplphysiol.00596.2024","DOIUrl":"https://doi.org/10.1152/japplphysiol.00596.2024","url":null,"abstract":"<p><p>Changes in ocular and brain structure and cerebral spinal fluid (CSF) dynamics from magnetic resonance imaging (MRI) data have been reported in astronauts following long-duration spaceflight. The purpose of this study was to quantify normal variation in these outcomes over a 2-year period in a healthy cohort similar in age to astronauts, but without spaceflight experience. Variation in MRI acquisition, observer measurement, or normal aging over a 2-year period was used to determine thresholds for interpreting measures following long duration spaceflight. Ten healthy participants (5 male) age 38 ± 8 years (mean ± SD) underwent five MRI sessions at baseline, 2, 6, 12, and 24 months to quantify intracranial volumetry, CSF dynamics, pituitary morphology, and ocular structures. Total within-person variation (σ²_<i>total</i>), modeled as the sum of the variance components for each outcome measure, was used to define a sensitivity threshold of 2.00 x σ²_<i>total</i>. Changes greater than these thresholds can be interpreted as a result of an intervention and have <5% probability of occurring due to expected variability. Thresholds for change due to all sources of variability were: 27 mL for gray matter volume, 16 mL for white matter volume, 0.9 mL for lateral ventricular volume, 26.0 µL for CSF aqueductal stroke volume, 3.2 cm/s for peak-to-peak aqueductal CSF velocity, 0.5 mm for pituitary height, 0.50 mm for optic nerve sheath diameter, and 10.2 mm³ for posterior optic globe volume displacement. Changes on brain MR images after an intervention need to exceed these thresholds to be attributable to that intervention.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144119753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impaired Neurovascular Coupling in Metabolic Syndrome: An fNIRS study.","authors":"Jigar Gosalia, Jocelyn M Delgado Spicuzza, Christine K Bowlus, Andrew W Gardner, Nancy A Dennis, James A Pawelczyk, David N Proctor","doi":"10.1152/japplphysiol.00893.2024","DOIUrl":"https://doi.org/10.1152/japplphysiol.00893.2024","url":null,"abstract":"<p><p><b>Purpose and Aims:</b> The mechanisms underpinning accelerated cognitive decline in metabolic syndrome (MetS) are poorly understood. Neurovascular coupling (NVC) is the coordinated matching of blood flow to neuronal activation and is dependent on endothelial function. NVC may drive blood flow dysregulation that contributes to neuronal damage and cognitive decline. The purpose was to assess NVC, peripheral endothelial function, and cognitive performance in older adults with MetS and healthy controls (CON), and the association of these factors. <b>Methods:</b> Older adults with and without MetS were recruited to complete a neurocognitive battery, assessment of NVC, and endothelial function. NVC was measured in the frontoparietal regions using functional near infrared spectroscopy (fNIRS) while participants completed the n-back task (0-,1-,2-back). Changes in oxyhemoglobin (HbO) and deoxyhemoglobin (HbR) signal reflected NVC during the n-back task. Endothelial function was measured using brachial ultrasound measurements of flow mediated dilation (%FMD). <b>Results:</b> MetS (n=22; age: 66±6) demonstrated poorer NVC during higher cognitive loads, reflected by an attenuated increase in HbO in the premotor cortex during the 2-back task compared to CON (n=26; age: 64±5) (p =0.036). MetS also demonstrated poorer FMD (5.55 ±1.35% vs. 4.42 ±1.71%, p =0.01) and 2-back accuracy compared to CON (MetS: 81.7 ± 6.4%; CON: 86.0 ±6.1%, p =0.027), with a significant positive association between these two factors (r=0.37, p =0.012). <b>Conclusions:</b> Impairments in NVC of the frontal cortex may be an early cerebrovascular mechanism underpinning cognitive decline in MetS and is discernible during higher cognitive loads. Peripheral endothelial dysfunction may be implicated in this mechanism.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144093565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}