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Grotle AK, Langlo JV, Holsbrekken E, Stone AJ, Tanaka H, Fadel PJ. Age-related alterations in the cardiovascular responses to acute exercise in males and females: role of the exercise pressor reflex. Front Physiol 2023; 14:1287392. [PMID: 38028783 PMCID: PMC10652405 DOI: 10.3389/fphys.2023.1287392] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 10/09/2023] [Indexed: 12/01/2023] Open
Abstract
Autonomic adjustments of the cardiovascular system are critical for initiating and sustaining exercise by facilitating the redistribution of blood flow and oxygen delivery to meet the metabolic demands of the active skeletal muscle. Afferent feedback from active skeletal muscles evokes reflex increases in sympathetic nerve activity and blood pressure (BP) (i.e., exercise pressor reflex) and contributes importantly to these primary neurovascular adjustments to exercise. When altered, this reflex contributes significantly to the exaggerated sympathetic and BP response to exercise observed in many cardiovascular-related diseases, highlighting the importance of examining the reflex and its underlying mechanism(s). A leading risk factor for the pathogenesis of cardiovascular disease in both males and females is aging. Although regular exercise is an effective strategy for mitigating the health burden of aging, older adults face a greater risk of experiencing an exaggerated cardiovascular response to exercise. However, the role of aging in mediating the exercise pressor reflex remains highly controversial, as conflicting findings have been reported. This review aims to provide a brief overview of the current understanding of the influence of aging on cardiovascular responses to exercise, focusing on the role of the exercise pressor reflex and proposing future directions for research. We reason that this review will serve as a resource for health professionals and researchers to stimulate a renewed interest in this critical area.
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Affiliation(s)
- A. K. Grotle
- Department of Sports, Food and Natural Science, Western Norway University of Applied Sciences, Bergen, Norway
| | - J. V. Langlo
- Department of Sports, Food and Natural Science, Western Norway University of Applied Sciences, Bergen, Norway
| | - E. Holsbrekken
- Department of Sports, Food and Natural Science, Western Norway University of Applied Sciences, Bergen, Norway
| | - A. J. Stone
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, United States
| | - H. Tanaka
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, United States
| | - P. J. Fadel
- Department of Kinesiology, The University of Texas at Arlington, Arlington, TX, United States
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de Bengy AF, Lamartine J, Sigaudo-Roussel D, Fromy B. Newborn and elderly skin: two fragile skins at higher risk of pressure injury. Biol Rev Camb Philos Soc 2022; 97:874-895. [PMID: 34913582 DOI: 10.1111/brv.12827] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 12/02/2021] [Accepted: 12/06/2021] [Indexed: 02/03/2023]
Abstract
Skin is a key organ maintaining internal homeostasis by performing many functions such as water loss prevention, body temperature regulation and protection from noxious substance absorption, microorganism intrusion and physical trauma. Skin ageing has been well studied and it is well known that physiological changes in the elderly result in higher skin fragility favouring the onset of skin diseases. For example, prolonged and/or high-intensity pressure may suppress local blood flow more easily, disturbing cell metabolism and inducing pressure injury (PI) formation. Pressure injuries (PIs) represent a significant problem worldwide and their prevalence remains too high. A higher PI prevalence is correlated with an elderly population. Newborn skin evolution has been less studied, but some data also report a higher PI prevalence in this population compared to older children, and several authors also consider this skin as physiologically fragile. In this review, we compare the characteristics of newborn and elderly skin in order to determine common features that may explain their fragility, especially regarding PI risk. We show that, despite differences in appearance, they share many common features leading to higher fragility to shear and pressure forces, not only at the structural level but also at the cellular and molecular level and in terms of physiology. Both newborn and elderly skin have: (i) a thinner epidermis; (ii) a thinner dermis containing a less-resistant collagen network, a higher collagen III:collagen I ratio and less elastin; (iii) a flatter dermal-epidermal junction (DEJ) with lower anchoring systems; and (iv) a thinner hypodermis, resulting in lower mechanical resistance to skin damage when pressure or shear forces are applied. At the molecular level, reduced expression of transforming growth factor β (TGFβ) and its receptor TGFβ receptor II (TβRII) is involved in the decreased production and/or increased degradation of various dermal extracellular matrix (ECM) components. Epidermal fragility also involves a higher skin pH which decreases the activity of key enzymes inducing ceramide deficiency and reduced barrier protection. This seems to be correlated with higher PI prevalence in some situations. Some data also suggest that stratum corneum (SC) dryness, which may disturb cell metabolism, also increases the risk of PI formation. Besides this structural fragility, several skin functions are also less efficient. Low applied pressures induce skin vessel vasodilation via a mechanism called pressure-induced vasodilation (PIV). Individuals lacking a normal PIV response show an early decrease in cutaneous blood flow in response to the application of very low pressures, reflecting vascular fragility of the skin that increases the risk of ulceration. Due to changes in endothelial function, skin PIV ability decreases during skin ageing, putting it at higher risk of PI formation. In newborns, some data lead us to hypothesize that the nitric oxide (NO) pathway is not fully functional at birth, which may partly explain the higher risk of PI formation in newborns. In the elderly, a lower PIV ability results from impaired functionality of skin innervation, in particular that of C-fibres which are involved in both touch and pain sensation and the PIV mechanism. In newborns, skin sensitivity differs from adults due to nerve system immaturity, but the role of this in PIV remains to be determined.
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Affiliation(s)
| | - Jérôme Lamartine
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, LBTI UMR5305, 7 Passage du Vercors, Lyon Cedex 7, F- 69367, France
| | - Dominique Sigaudo-Roussel
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, LBTI UMR5305, 7 Passage du Vercors, Lyon Cedex 7, F- 69367, France
| | - Bérengère Fromy
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, LBTI UMR5305, 7 Passage du Vercors, Lyon Cedex 7, F- 69367, France
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Oto T, Urata K, Hayashi Y, Hitomi S, Shibuta I, Iwata K, Iinuma T, Shinoda M. Age-Related Differences in Transient Receptor Potential Vanilloid 1 and 2 Expression Patterns in the Trigeminal Ganglion Neurons Contribute to Changes in the Palatal Mucosal Heat Pain Sensitivity. TOHOKU J EXP MED 2022; 256:283-290. [PMID: 35296569 DOI: 10.1620/tjem.2022.j004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Tatsuki Oto
- Department of Complete Denture Prosthodontics, Nihon University School of Dentistry
| | - Kentaro Urata
- Department of Complete Denture Prosthodontics, Nihon University School of Dentistry
| | | | - Suzuro Hitomi
- Department of Physiology, Nihon University School of Dentistry
| | - Ikuko Shibuta
- Department of Physiology, Nihon University School of Dentistry
| | - Koichi Iwata
- Department of Physiology, Nihon University School of Dentistry
| | - Toshimitsu Iinuma
- Department of Complete Denture Prosthodontics, Nihon University School of Dentistry
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Roh YS, Choi J, Sutaria N, Kwatra SG. Itch: Epidemiology, clinical presentation, and diagnostic workup. J Am Acad Dermatol 2022; 86:1-14. [PMID: 34428534 PMCID: PMC8678917 DOI: 10.1016/j.jaad.2021.07.076] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 07/24/2021] [Accepted: 07/28/2021] [Indexed: 01/03/2023]
Abstract
Itch, or pruritus, is the uncomfortable sensation underlying the desire to scratch. Itch is a very common complaint in the general population that can result from dermatologic, systemic (eg, renal, hepatobiliary, endocrine), paraneoplastic, neuropathic, and psychogenic etiologies. Chronic itch is associated with significant sleep disturbances and profoundly reduces overall quality of life. Certain populations, including elderly and African Americans, are at increased risk of experiencing heightened burden of itch. Because of the variable clinical presentation and wide-ranging etiologies, itch presents a challenge for clinicians. The initial evaluation should include a complete blood count, with differential, hepatic, renal, and thyroid function testing along with diabetes screening. Further testing should be guided by history and physical examination findings. There should be a heightened concern for underlying malignancy in individuals older than 60 years of age who have a history of liver disease and diffuse itch less than 12 months of duration. For individuals with chronic pruritus of unknown origin, increased blood eosinophils may serve as a biomarker of T helper cell type 2 polarization and response to immunomodulator therapies. In this first part of a 2-part continuing medical education series, we describe the broader epidemiology and specific conditions associated with itch and the clinical presentation and diagnostic workup for patients with itch.
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Affiliation(s)
- Youkyung S. Roh
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Justin Choi
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Nishadh Sutaria
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Shawn G. Kwatra
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland
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5
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Johnson AJ, Wilson AT, Laffitte Nodarse C, Montesino-Goicolea S, Valdes-Hernandez PA, Somerville J, Peraza JA, Fillingim RB, Bialosky J, Cruz-Almeida Y. Age Differences in Multimodal Quantitative Sensory Testing and Associations With Brain Volume. Innov Aging 2021; 5:igab033. [PMID: 34616958 PMCID: PMC8489433 DOI: 10.1093/geroni/igab033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND OBJECTIVES Somatosensory function is critical for successful aging. Prior studies have shown declines in somatosensory function with age; however, this may be affected by testing site, modality, and biobehavioral factors. While somatosensory function declines are associated with peripheral nervous system degradation, little is known regarding correlates with the central nervous system and brain structure in particular. The objectives of this study were to examine age-related declines in somatosensory function using innocuous and noxious stimuli, across 2 anatomical testing sites, with considerations for affect and cognitive function, and associations between somatosensory function and brain structure in older adults. RESEARCH DESIGN AND METHODS A cross-sectional analysis included 84 "younger" (n = 22, age range: 19-24 years) and "older" (n = 62, age range: 60-94 years) healthy adults who participated in the Neuromodulatory Examination of Pain and Mobility Across the Lifespan study. Participants were assessed on measures of somatosensory function (quantitative sensory testing), at 2 sites (metatarsal and thenar) using standardized procedures, and completed cognitive and psychological function measures and structural magnetic resonance imaging. RESULTS Significant age × test site interaction effects were observed for warmth detection (p = .018,η p 2 = 0.10) and heat pain thresholds (p = .014,η p 2 = 0.12). Main age effects were observed for mechanical, vibratory, cold, and warmth detection thresholds (ps < .05), with older adults displaying a loss of sensory function. Significant associations between somatosensory function and brain gray matter structure emerged in the right occipital region, the right temporal region, and the left pericallosum. DISCUSSION AND IMPLICATIONS Our findings indicate healthy older adults display alterations in sensory responses to innocuous and noxious stimuli compared to younger adults and, furthermore, these alterations are uniquely affected by anatomical site. These findings suggest a nonuniform decline in somatosensation in older adults, which may represent peripheral and central nervous system alterations part of aging processes.
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Affiliation(s)
- Alisa J Johnson
- Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, Florida, USA
- Department of Community Dentistry & Behavioral Sciences, College of Dentistry, University of Florida, Gainesville, Florida, USA
| | - Abigail T Wilson
- Department of Physical Therapy, College of Public Health and Health Professions, University of Florida, Gainesville, Florida, USA
- Brooks Rehabilitation–College of Public Health and Health Professions Research Collaboration, Gainesville, Florida, USA
| | - Chavier Laffitte Nodarse
- Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, Florida, USA
| | - Soamy Montesino-Goicolea
- Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, Florida, USA
| | - Pedro A Valdes-Hernandez
- Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, Florida, USA
- Department of Community Dentistry & Behavioral Sciences, College of Dentistry, University of Florida, Gainesville, Florida, USA
| | - Jessie Somerville
- Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, Florida, USA
| | - Julio A Peraza
- Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, Florida, USA
| | - Roger B Fillingim
- Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, Florida, USA
- Department of Community Dentistry & Behavioral Sciences, College of Dentistry, University of Florida, Gainesville, Florida, USA
| | - Joel Bialosky
- Department of Physical Therapy, College of Public Health and Health Professions, University of Florida, Gainesville, Florida, USA
- Brooks Rehabilitation–College of Public Health and Health Professions Research Collaboration, Gainesville, Florida, USA
| | - Yenisel Cruz-Almeida
- Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, Florida, USA
- Department of Community Dentistry & Behavioral Sciences, College of Dentistry, University of Florida, Gainesville, Florida, USA
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Daguet I, Bergeron-Vezina K, Harvey MP, Martel M, Coulombe-Leveque A, Leonard G. Decreased Initial Peak Pain Sensation with Aging: A Psychophysical Study. J Pain Res 2020; 13:2333-2341. [PMID: 33061548 PMCID: PMC7519834 DOI: 10.2147/jpr.s257791] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Accepted: 06/17/2020] [Indexed: 11/23/2022] Open
Abstract
Background and Purpose Aging is associated with an impairment of diverse physiological functions, including nociception. For example, older adults in comparison to young adults, show an overall increase in pain thresholds, reflecting a decline in pain sensitivity and changes in the nociceptive pathways. These results are, however, debated as they were not always replicated depending on the stimulus modality, duration, and location. The aim of the current study was to determine how the temporal evolution of pain intensity during a continuous tonic heat pain test is influenced by aging. More specifically, we wanted to 1) assess the effect of age on initial peak and late-phase pain and 2) determine whether potential age effects depend on the stimulation site. Participants and Methods 13 young adults (average of 27.9 years old) and 13 older adults (average of 67.5 years old) participated in this study. Experimental heat pain was evoked on an appendicular (forearm) and axial (lower-back) body region, using a thermode (2-minute stimulation at a constant, individually-adjusted temperature). During the nociceptive stimulation, participants used a computerized visual analogue scale to continuously rate their pain. Results We show that initial peak (0-30 seconds) pain sensation was significantly lower in older adults compared to young adults, while late-phase (30-120 seconds) pain sensation was similar across the two age groups. These results hold true for both stimulation sites, suggesting the existence of an age effect on both appendicular and axial body regions. Conclusion The lower magnitude of initial peak pain observed in older adults, which affects both appendicular and axial body regions, could reflect generalized peripheral or central alterations of the nociceptive system in older adults. These alterations in older adults could have significant clinical impacts, such as an increased vulnerability to injury or an underestimation of the severity of their pain condition.
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Affiliation(s)
- Ines Daguet
- Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada.,Research Centre on Aging, CIUSSS de l'Estrie - CHUS, Sherbrooke, QC, Canada
| | - Kayla Bergeron-Vezina
- Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada.,Research Centre on Aging, CIUSSS de l'Estrie - CHUS, Sherbrooke, QC, Canada
| | - Marie-Philippe Harvey
- Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada.,Research Centre on Aging, CIUSSS de l'Estrie - CHUS, Sherbrooke, QC, Canada
| | - Marylie Martel
- Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada.,Research Centre on Aging, CIUSSS de l'Estrie - CHUS, Sherbrooke, QC, Canada
| | - Alexia Coulombe-Leveque
- Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada.,Research Centre on Aging, CIUSSS de l'Estrie - CHUS, Sherbrooke, QC, Canada.,School of Rehabilitation, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Guillaume Leonard
- Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada.,Research Centre on Aging, CIUSSS de l'Estrie - CHUS, Sherbrooke, QC, Canada.,School of Rehabilitation, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
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7
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García-Piqueras J, García-Mesa Y, Cárcaba L, Feito J, Torres-Parejo I, Martín-Biedma B, Cobo J, García-Suárez O, Vega JA. Ageing of the somatosensory system at the periphery: age-related changes in cutaneous mechanoreceptors. J Anat 2019; 234:839-852. [PMID: 30924930 DOI: 10.1111/joa.12983] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/19/2019] [Indexed: 12/19/2022] Open
Abstract
Decline of tactile sensation associated with ageing depends on modifications in skin and both central and peripheral nervous systems. At present, age-related changes in the periphery of the somatosensory system, particularly concerning the effects on mechanoreceptors, remain unknown. Here we used immunohistochemistry to analyse the age-dependent changes in Meissner's and Pacinian corpuscles as well as in Merkel cell-neurite complexes. Moreover, variations in the neurotrophic TrkB-BDNF system and the mechanoprotein Piezo2 (involved in maintenance of cutaneous mechanoreceptors and light touch, respectively) were evaluated. The number of Meissner's corpuscles and Merkel cells decreased progressively with ageing. Meissner's corpuscles were smaller, rounded in morphology and located deeper in the dermis, and signs of corpuscular denervation were found in the oldest subjects. Pacinian corpuscles generally showed no relevant age-related alterations. Reduced expression of Piezo2 in the axon of Meissner's corpuscles and in Merkel cells was observed in old subjects, as well was a decline in the BDNF-TrkB neurotrophic system. This study demonstrates that cutaneous Meissner's corpuscles and Merkel cell-neurite complexes (and less evidently Pacinian corpuscles) undergo morphological and size changes during the ageing process, as well as a reduction in terms of density. Furthermore, the mechanoprotein Piezo2 and the neurotrophic TrkB-BDNF system are reduced in aged corpuscles. Taken together, these alterations might explain part of the impairment of the somatosensory system associated with ageing.
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Affiliation(s)
- Jorge García-Piqueras
- Departamento de Morfología y Biología Celular, Grupo SINPOS Universidad de Oviedo, Oviedo, Spain
| | - Yolanda García-Mesa
- Departamento de Morfología y Biología Celular, Grupo SINPOS Universidad de Oviedo, Oviedo, Spain
| | - Lucia Cárcaba
- Departamento de Morfología y Biología Celular, Grupo SINPOS Universidad de Oviedo, Oviedo, Spain
| | - Jorge Feito
- Departamento de Morfología y Biología Celular, Grupo SINPOS Universidad de Oviedo, Oviedo, Spain.,Servicio de Anatomía Patológica, Hospital Universitario de Salamanca, Salamanca, Spain
| | - Isidro Torres-Parejo
- Departamento de Morfología y Biología Celular, Grupo SINPOS Universidad de Oviedo, Oviedo, Spain
| | - Benjamín Martín-Biedma
- Departamento de Cirugía y Especialidades Médico-Quirúrgicas, Universidad de Santiago de Compostela, Santiago de Compostela, Spain
| | - Juan Cobo
- Departamento de Cirugía y Especialidades Médico-Quirúrgicas, Universidad de Oviedo, Oviedo, Spain.,Instituto Asturiano de Odontología, Oviedo, Spain
| | - Olivia García-Suárez
- Departamento de Morfología y Biología Celular, Grupo SINPOS Universidad de Oviedo, Oviedo, Spain
| | - Jose A Vega
- Departamento de Morfología y Biología Celular, Grupo SINPOS Universidad de Oviedo, Oviedo, Spain.,Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile
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Caron G, Decherchi P, Marqueste T. Alteration of Metabosensitive Afferent Response With Aging: Exercised versus Non-exercised Rats. Front Aging Neurosci 2018; 10:367. [PMID: 30483115 PMCID: PMC6240616 DOI: 10.3389/fnagi.2018.00367] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 10/23/2018] [Indexed: 01/24/2023] Open
Abstract
This study was designed to evaluate the effect of aging on the activity of metabosensitive afferent fibers (thin muscle afferents from group III and IV) and to determine if physical activity performed at old age may influence the afferent discharge. Afferents from tibialis anterior and soleus muscles were recorded on non-exercised rats aged of 3, 6, 12, and 20 months and on animals aged of 12 and 20 months performing a daily incremental treadmill exercise protocol during the last 8 weeks preceding the recordings. Metabosensitive afferent fibers were activated with potassium chloride (KCl) and lactic acid (LA) injections into the blood stream or by muscle electrically-induced fatigue (EIF). Results indicated that aging is associated to a decrease in the magnitude of the responses to chemical injections and EIF. Unfortunately, physical activity did not allow restoring the metabosensitive afferents responses. These results indicate an alteration of the thin afferent fibers with aging and should be taken into account regarding the management of muscle fatigue and potential alterations of exercise pressor reflex (EPR) occurring with aging.
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Affiliation(s)
- Guillaume Caron
- Aix-Marseille Univ, CNRS, ISM, Equipe Plasticité des Systèmes Nerveux et Musculaire, Faculté des Sciences du Sport, Marseille, France
| | - Patrick Decherchi
- Aix-Marseille Univ, CNRS, ISM, Equipe Plasticité des Systèmes Nerveux et Musculaire, Faculté des Sciences du Sport, Marseille, France
| | - Tanguy Marqueste
- Aix-Marseille Univ, CNRS, ISM, Equipe Plasticité des Systèmes Nerveux et Musculaire, Faculté des Sciences du Sport, Marseille, France
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Abstract
With worldwide expansion of the aging population, research on age-related pathologies is receiving growing interest. In this review, we discuss current knowledge regarding the decline of skin structure and function induced by the passage of time (chronological aging) and chronic exposure to solar UV irradiation (photoaging). Nearly every aspect of skin biology is affected by aging. The self-renewing capability of the epidermis, which provides vital barrier function, is diminished with age. Vital thermoregulation function of eccrine sweat glands is also altered with age. The dermal collagenous extracellular matrix, which comprises the bulk of skin and confers strength and resiliency, undergoes gradual fragmentation, which deleteriously impacts skin mechanical properties and dermal cell functions. Aging also affects wound repair, pigmentation, innervation, immunity, vasculature, and subcutaneous fat homeostasis. Altogether, age-related alterations of skin lead to age-related skin fragility and diseases.
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10
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Kemp J, Després O, Pebayle T, Dufour A. Differences in age-related effects on myelinated and unmyelinated peripheral fibres: A sensitivity and evoked potentials study. Eur J Pain 2013; 18:482-8. [DOI: 10.1002/j.1532-2149.2013.00388.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/22/2013] [Indexed: 11/08/2022]
Affiliation(s)
- J. Kemp
- Laboratoire de Neurosciences Cognitives et Adaptatives; UdS-CNRS; Strasbourg France
| | - O. Després
- Laboratoire de Neurosciences Cognitives et Adaptatives; UdS-CNRS; Strasbourg France
| | - T. Pebayle
- Centre d'Investigations Neurocognitives et Neurophysiologiques; UdS-CNRS; Strasbourg France
| | - A. Dufour
- Laboratoire de Neurosciences Cognitives et Adaptatives; UdS-CNRS; Strasbourg France
- Centre d'Investigations Neurocognitives et Neurophysiologiques; UdS-CNRS; Strasbourg France
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