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1.
Nurs Health Sci ; 25(3): 341-353, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37431643

RESUMO

Dance programs promote physical and psychosocial well-being. However, studies focusing on the experiences of older adults in dancing are limited. This study aims to develop a community dance program (CDP) for older adults at senior activity centers in Singapore, as well as to explore the older adults' and student instructors' experiences of the CDP. A qualitative inquiry of semi-structured and in-depth focus group discussions was conducted. In total, 20 older adults and 10 student dance instructors participated in the study. Student instructors who were undergraduate students from a dance society were trained in how to provide step-by-step instructions for the older adults. An inductive approach of thematic analysis was undertaken. Three main themes were identified: (i) promotion of physical, cognitive, and psychosocial health with dance; (ii) imagination is power-travel through dance; and (iii) further enhancement of the dance program. The themes highlighted the prominence of CDP in improving memory, physical health, mood, and social interactions-thus mitigating the risk of social isolation. The findings illustrated the benefits of CDP in cultivating intergenerational bonds amongst older adults and student instructors.


Assuntos
Exame Físico , Humanos , Idoso , Singapura , Pesquisa Qualitativa , Grupos Focais
2.
J Transl Med ; 19(1): 71, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33593349

RESUMO

Skeletal muscle aging is associated with a decline in motor function and loss of muscle mass- a condition known as sarcopenia. The underlying mechanisms that drive this pathology are associated with a failure in energy generation in skeletal muscle, either from age-related decline in mitochondrial function, or from disuse. To an extent, lifelong exercise is efficacious in preserving the energetic properties of skeletal muscle and thus may delay the onset of sarcopenia. This review discusses the cellular and molecular changes in skeletal muscle mitochondria during the aging process and how different exercise modalities work to reverse these changes. A key factor that will be described is the efficiency of mitochondrial coupling-ATP production relative to O2 uptake in myocytes and how that efficiency is a main driver for age-associated decline in skeletal muscle function. With that, we postulate the most effective exercise modality and protocol for reversing the molecular hallmarks of skeletal muscle aging and staving off sarcopenia. Two other concepts pertinent to mitochondrial efficiency in exercise-trained skeletal muscle will be integrated in this review, including- mitophagy, the removal of dysfunctional mitochondrial via autophagy, as well as the implications of muscle fiber type changes with sarcopenia on mitochondrial function.


Assuntos
Sarcopenia , Idoso , Envelhecimento , Exercício Físico , Humanos , Mitocôndrias , Músculo Esquelético/patologia , Sarcopenia/metabolismo , Sarcopenia/prevenção & controle
3.
Exp Physiol ; 105(4): 622-631, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31977105

RESUMO

What is the central question of this study? Fibroblast growth factor 21 (FGF21) plays important therapeutic roles in metabolic diseases but is associated with bone loss, through insulin-like growth factor binding protein 1 (IGFBP1), in animals. However, the effect of the FGF21-IGFBP1 axis on age-related bone loss has not been explored in humans. What is the main finding and its importance? Using 'genetically linked' parent and child family pairs, we show that the FGF21 concentration, but not the IGFBP1 concentration, is higher in older than in younger adults. Our results suggest that age-associated decline in bone mineral density is associated with FGF21 and increased bone turnover but not likely to involve IGFBP1 in healthy humans. ABSTRACT: Bone fragility increases with age. The fibroblast growth factor 21 (FGF21)-insulin-like growth factor binding protein 1 (IGFBP1) axis regulates bone loss in animals. However, the role of FGF21 in mediating age-associated bone fragility in humans remains unknown. The purpose of this study was to explore the FGF21-regulatory axis in bone turnover and the age-related decline in bone mineral density (BMD). Twenty 'genetically linked' family (parent and child) pairs were recruited. Younger adults were 22-39 years old and older adults 60-71 years old. The BMD and serum concentrations of FGF21, IGFBP1, receptor activator of nuclear factor-κB ligand (RANKL), tartrate-resistant acid phosphatase 5b (TRAP5b) and bone-specific alkaline phosphatase (BAP) were measured. Older adults had 10-18% lower BMD at the hip and spine (P < 0.008) and a twofold higher FGF21 concentration (P < 0.001). The IGFBP1 concentration was similar in younger and older adults (P = 0.961). The RANKL concentration was 44% lower (P = 0.006), whereas TRAP5b and BAP concentrations were 36 and 31% higher (P = 0.01 and P = 0.004), respectively, in older adults than in younger adults. Adjusting for sex did not affect these results. The FGF21 concentration was negatively correlated with BMD at the spine (r = -0.460, P = 0.003), but not with the IGFBP1 concentration (r = -0.144, P = 0.374). The IGFBP1 concentration was not correlated with BMD at the hip or spine (all P > 0.05). In humans, FGF21 might be involved in the age-associated decline in BMD, especially at the spine, through increased bone turnover. IGFBP1 is unlikely to be the downstream effector of FGF21 in driving the age-associated decline in BMD and in RANKL-associated osteoclast differentiation.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Osteoporose/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ligante RANK/metabolismo , Adulto Jovem
4.
Cytokine ; 110: 222-225, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30041123

RESUMO

The "danger" model of immunology states that the immune system detects and responds to danger by releasing endogenous molecules called alarmins. Strenuous exercise perturbs physiological homeostasis, increasing circulating alarmins to drive the inflammatory response. We describe a working concept of exercise-induced High Mobility Group Box (HMGB)1, a prototypical alarmin, in modulating immune responses and adaptations.


Assuntos
Exercício Físico/fisiologia , Proteína HMGB1/imunologia , Sistema Imunitário/imunologia , Adaptação Biológica/imunologia , Alarminas/imunologia , Homeostase/imunologia , Humanos , Inflamação/imunologia , Pessoa de Meia-Idade
5.
Heliyon ; 10(13): e33488, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39035501

RESUMO

Importance: The burgeoning landscape of wearable devices warrants a guide for the selection of devices. Existing guidelines and recommendations provide evaluation frameworks with theoretical principles but tend to lack a pragmatic application and systematic approach for device selection. While fitness trackers exemplify the convenience of wearable technologies, their selection for specific health monitoring purposes demands a nuanced understanding of varying functionalities and user compatibilities. Objective: The objective is to develop and present a practical guide for researchers, healthcare professionals, and device users to systematically select wearable devices for continuous monitoring in community-dwelling adults. Methods & results: Based on diverse sources, such as the United States Food and Drug Administration (FDA), the Clinical Trials Transformation Initiative (CTTI), the Electronic Patient-Reported Outcome (ePRO) Consortium, and comparative analyses of wearable technology performances from feasibility and usability studies, the guide incorporates five core criteria: continuous monitoring capability, device availability and suitability, technical performance (accuracy and precision), feasibility of use, and cost evaluation. The structured criteria can be applied in device selection as well as device evaluation. Conclusions: This practical guide provides a step-by-step solution for researchers, healthcare professionals, and device users to choose suitable wearable devices for continuous monitoring. It provides a comprehensive starting point, outlining how to effectively navigate the selection process for wearable devices amidst a plethora of similar options.

6.
Geroscience ; 46(1): 219-239, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37851316

RESUMO

Functional decline of physiological systems during ageing leads to age-related diseases. Dietary glycine increases healthy lifespan in model organisms and might decrease inflammation in humans, suggesting its geroprotective potential. This review summarises the evidence of glycine administration on the characteristics of eleven physiological systems in adult humans. Databases were searched using key search terms: 'glycine', 'adult', 'supplementation'/ 'administration'/ 'ingestion'/ 'treatment'. Glycine was administered to healthy and diseased populations (18 and 34 studies) for up to 14 days and 4 months, respectively. The nervous system demonstrated the most positive effects, including improved psychiatric symptoms from longer-term glycine administration in psychiatric populations. While longer-term glycine administration improved sleep in healthy populations, these studies had small sample sizes with a high risk of bias. Larger and long-term studies with more robust study designs in healthy populations to examine the effects of glycine administration on preventing, delaying or reversing the ageing process are warranted.


Assuntos
Suplementos Nutricionais , Glicina , Nível de Saúde , Humanos , Glicina/administração & dosagem
7.
Geroscience ; 46(6): 6029-6038, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38546907

RESUMO

Breast cancer (BC) is the most prominent cancer amongst women, but fortunately, early diagnosis and advances in multimodality treatments have improved patient survivability. Cancer survivors, however, experience increased biological ageing which may accelerate other co-morbidities. Exercise intervention is a promising clinical adjuvant approach to improve BC patients' physiological function, recovery from treatment, and quality of life. However, the effects of combined aerobic and strength exercise training on biological ageing in BC patients have not been studied. The Breast Cancer Exercise Intervention (BREXINT) Pilot Study will evaluate the effects of a 24-week combined aerobic and strength exercise intervention against usual care in 50 BC patients' post-treatment randomised to either group. The primary outcomes include changes in cardiorespiratory fitness, muscle strength, cancer-related symptoms, and rate of biological ageing following exercise intervention period. The secondary outcomes include habitual physical activity measured with tri-axial accelerometery and supporting questionnaires, including physical activity, food diary, and quality of life questionnaires. This study will identify the effects of combined aerobic exercise strength training on biological ageing in BC patients from Singapore. Results from this study could further support the implementation of regular exercise programmes as routine care for cancer patients.


Assuntos
Neoplasias da Mama , Exercício Físico , Qualidade de Vida , Treinamento Resistido , Humanos , Feminino , Neoplasias da Mama/reabilitação , Neoplasias da Mama/terapia , Projetos Piloto , Singapura , Treinamento Resistido/métodos , Exercício Físico/fisiologia , Envelhecimento/fisiologia , Força Muscular/fisiologia , Terapia por Exercício/métodos , Pessoa de Meia-Idade , Idoso , Aptidão Cardiorrespiratória/fisiologia , Adulto
8.
Geroscience ; 46(5): 4505-4515, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38589672

RESUMO

Geriatric rehabilitation inpatients have high levels of sedentary behaviour (SB) and low levels of physical activity (PA). Biological age predicted by blood biomarkers is indicative of adverse outcomes. The objective was to determine the association between blood biological age at rehabilitation admission and levels of SB and PA during rehabilitation in geriatric inpatients. Inpatients admitted to geriatric rehabilitation wards at the Royal Melbourne Hospital (Melbourne, Australia) from October 22, 2019, to March 29, 2020, in the REStORing health of acute unwell adulTs (RESORT) observational cohort were included. Blood biological age was predicted using SenoClock-BloodAge, a hematological ageing clock. Patients wore an inertial sensor to measure SB and PA. Logistic regression analyses were conducted. A total of 111 patients (57.7% female) with mean age 83.3 ± 7.5 years were included in the analysis. The mean blood biological age was 82.7 ± 8.4 years. Patients with 1-year higher blood biological age had higher odds of having high SB measured as non-upright time greater than 23 h/day (odds ratio (OR): 1.050, 95% confidence interval (CI): 1.000-1.102). Individuals having 1-year higher age deviation trended towards lower odds of having high levels of PA measured as stepping time greater than 7.4 min/day (OR: 0.916, CI: 0.836-1.005) and as greater than 19.5 sit-to-stand transitions/day (OR: 0.915, CI: 0.836-1.002). In conclusion, higher biological age was associated with higher levels of SB and trended towards lower PA. Incorporating blood biological age could facilitate resource allocation and the development of more tailored rehabilitation plans.


Assuntos
Exercício Físico , Humanos , Feminino , Masculino , Idoso de 80 Anos ou mais , Exercício Físico/fisiologia , Idoso , Comportamento Sedentário , Pacientes Internados , Avaliação Geriátrica/métodos , Austrália , Hospitalização
9.
Sports Health ; : 19417381241271547, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39233399

RESUMO

CONTEXT: Ketogenic diets and ketone supplements have gained popularity among endurance runners given their purported effects: potentially delaying the onset of fatigue by enabling the increased utilization of the body's fat reserve or external ketone bodies during prolonged running. OBJECTIVE: This systematic review was conducted to evaluate the effects of ketogenic diets (>60% fat and <10% carbohydrates/<50 g carbohydrates per day) or ketone supplements (ketone esters or ketone salts, medium-chain triglycerides or 1,3-butadiol) on the aerobic performance of endurance runners. DATA SOURCES: A systematic search was conducted in PubMed, Web of Science, Pro Quest, and Science Direct for publications up to October 2023. STUDY SELECTION: Human studies on the effects of ketogenic diets or ketone supplements on the aerobic performance of adult endurance runners were included after independent screening by 2 reviewers. STUDY DESIGN: Systematic review. LEVEL OF EVIDENCE: Level 3. DATA EXTRACTION: Primary outcomes were markers of aerobic performance (maximal oxygen uptake [VO2max], race time, time to exhaustion and rate of perceived exertion). RESULTS: VO2max was assessed by incremental test to exhaustion. Endurance performance was assessed by time trials, 180-minute running trials, or run-to-exhaustion trials; 5 studies on ketogenic diets and 7 studies on ketone supplements involving a total of 132 endurance runners were included. Despite the heterogeneity in study design and protocol, none reported benefits of ketogenic diets or ketone supplements on selected markers of aerobic performance compared with controls. Reduction in bodyweight and fat while preserving lean mass and improved glycemic control were reported in some included studies on ketogenic diets. CONCLUSION: This review did not identify any significant advantages or disadvantages of ketogenic diets or ketone supplements for the aerobic performance of endurance runners. Further trials with larger sample sizes, more gender-balanced participants, longer ketogenic diet interventions, and follow-up on metabolic health are warranted.

10.
BMC Sports Sci Med Rehabil ; 15(1): 68, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37127789

RESUMO

Cardiopulmonary exercise testing (CPET) is an important tool to measure the cardiopulmonary fitness of an individual and has been widely used in athletic, clinical and research settings. Most CPET focus on analyzing physiological responses during exercise. We contend that the post-CPET recovery physiological responses offer further diagnostic and prognostic information about the health of the cardiopulmonary and metabolic systems, especially when testing apparently healthy middle-aged and older adults. However, there are limited studies that investigate physiological responses during the post-CPET recovery, and even less so in middle-aged and older adults. Therefore, this current review is aimed at discussing the contribution of post-CPET recovery parameters to cardiopulmonary health and their potential applications in aging populations. In addition to the existing methods, we propose to examine the aerobic and anaerobic recovery threshold post-CPET as novel potential diagnostic and/or prognostic tools.

11.
FEBS J ; 290(3): 649-668, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34968001

RESUMO

Biological aging is the main driver of age-associated chronic diseases. In 2014, the United States National Institute of Aging (NIA) sponsored a meeting between several investigators in the field of aging biology, who identified seven biological pillars of aging and a consensus review, "Geroscience: Linking Aging to Chronic Disease," was published. The pillars of aging demonstrated the conservation of aging pathways in diverse model organisms and thus represent a useful framework with which to study human aging. In this present review, we revisit the seven pillars of aging from the perspective of exercise and discuss how regular physical exercise can modulate these pillars to stave off age-related chronic diseases and maintain functional capacity.


Assuntos
Envelhecimento , Exercício Físico , Humanos , Estados Unidos , Envelhecimento/genética , Envelhecimento/metabolismo , Doença Crônica
12.
Geroscience ; 45(5): 2939-2950, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37204639

RESUMO

Remote monitoring technologies (RMTs) allow continuous, unobtrusive, and real-time monitoring of the cardiovascular system. An overview of existing RMTs measuring cardiovascular physiological variables is lacking. This systematic review aimed to describe RMTs measuring cardiovascular functions in community-dwelling adults. An electronic search was conducted via PubMed, EMBASE, and Cochrane Library from January 1, 2020, to April 7, 2022. Articles reporting on non-invasive RMTs used unsupervised in community-dwelling adults were included. Reviews and studies in institutionalized populations were excluded. Two reviewers independently assessed the studies and extracted the technologies used, cardiovascular variables measured, and wearing locations of RMTs. Validation of the RMTs was examined based on the COSMIN tool, and accuracy and precision were presented. This systematic review was registered with PROSPERO (CRD42022320082). A total of 272 articles were included representing 322,886 individuals with a mean or median age from 19.0 to 88.9 years (48.7% female). Of all 335 reported RMTs containing 216 distinct devices, photoplethysmography was used in 50.3% of RMTs. Heart rate was measured in 47.0% of measurements, and the RMT was worn on the wrist in 41.8% of devices. Nine devices were reported in more than three articles, of which all were sufficiently accurate, six were sufficiently precise, and four were commercially available in December 2022. The top four most reported technologies were AliveCor KardiaMobile®, Fitbit Charge 2, and Polar H7 and H10 Heart Rate Sensors. With over 200 distinct RMTs reported, this review provides healthcare professionals and researchers an overview of available RMTs for monitoring the cardiovascular system.


Assuntos
Sistema Cardiovascular , Tecnologia de Sensoriamento Remoto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Vida Independente , Adulto Jovem , Adulto , Pessoa de Meia-Idade
13.
Aging (Albany NY) ; 15(6): 1768-1790, 2023 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-36934330

RESUMO

Brief (10 min) weekly exposure to low energy pulsed electromagnetic fields (PEMFs) has been shown to improve human muscle mitochondrial bioenergetics and attenuate systemic lipotoxicity following anterior cruciate ligament surgical reconstruction. Here we present data generated from 101 participants, 62% female, aged 38-91 years, recruited from the QuantumTx Demo Centre in Singapore, wherein 87% of participants (n = 88) presented with pre-existing mobility dysfunction and 13% (n = 13) were healthy volunteers. Participants were recruited if: (i) not pregnant; (ii) above 35 years of age and; (iii) without surgical implants. All participants completed mobility testing, pre- and post- PEMF intervention for 12 weeks, whereas bioelectrical impedance analysis was conducted in a subgroup of 42 and 33 participants at weeks 4 and 8, respectively. Weekly PEMF exposure was associated with significant improvements in mobility (Timed Up and Go, 5 times Sit-to-Stand, and 4m Normal Gait Speed) and body composition (increased skeletal muscle mass and reduced total and visceral fat mass), particularly in the older participants. Perception of pain was also significantly reduced. PEMF therapy may provide a manner to counteract age-associated mobility and metabolic disruptions and merits future investigation in randomized controlled trials to elucidate its clinical benefits in the frail and older adult populations.


Assuntos
Reconstrução do Ligamento Cruzado Anterior , Magnetoterapia , Músculo Esquelético , Idoso , Feminino , Humanos , Masculino , Sudeste Asiático , Composição Corporal , Fenômenos Magnéticos , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais
14.
Geroscience ; 45(5): 2897-2907, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37217632

RESUMO

Targeting molecular processes of aging will enable people to live healthier and longer lives by preventing age-related diseases. Geroprotectors are compounds with the potential to increase healthspan and lifespan. Even though many of them have been tested in animal models, the translation to humans is limited. Alpha-Ketoglutarate (AKG) has been studied widely in model animals, but there are few studies testing its geroprotective properties in humans. ABLE is a double blinded placebo-controlled randomized trial (RCT) of 1 g sustained release Ca-AKG versus placebo for 6 months of intervention and 3 months follow up including 120 40-60-year-old healthy individuals with a higher DNA methylation age compared to their chronological age. The primary outcome is the decrease in DNA methylation age from baseline to the end of the intervention. A total of 120 participants will be randomized to receive either sustained release Ca-AKG or placebo. Secondary outcomes include changes in the inflammatory and metabolic parameters in blood, handgrip strength and leg extension strength, arterial stiffness, skin autofluorescence, and aerobic capacity from baseline to 3 months, 6 months, and 9 months. This study will recruit middle-aged participants with an older DNA methylation age compared to their chronological age, and test whether supplementation with Ca-AKG can reduce DNA methylation age. This study is unique in its inclusion of biologically older participants.


Assuntos
Força da Mão , Ácidos Cetoglutáricos , Animais , Humanos , Pessoa de Meia-Idade , Ácidos Cetoglutáricos/farmacologia , Preparações de Ação Retardada , Envelhecimento , Suplementos Nutricionais , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Exerc Immunol Rev ; 18: 158-76, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22876727

RESUMO

Regular exercise and physical activity provide many health benefits and are encouraged by medical professionals for the primary prevention of and adjuvant treatment of breast cancer Current consensus in the discipline of exercise oncology is that both regular physical activity and exercise training exert some protective effect against breast cancer risk, and may reduce morbidity in some advanced cases. While there is growing interest in the role of exercise and physical activity in breast cancer prevention, it is currently unclear how exercise may modulate tumor behavior. The tumor microenvironment is populated by stromal cells such as fibroblasts and adipocytes, as well as macrophages. Termed tumor-associated macrophages (TAMs), these immune cells are highly plastic and respond to different signals from the cancer microenvironment, causing them to either display tumor-promoting or tumor-suppressing phenotypes. Because of such plasticity, there has been considerable interest by immunologists to develop immunotherapies based on skewing the behavior of TAMs to become cancer-suppressive. Previous studies have indirectly shown the ability of exercise training to induce an anti-tumor effect of macrophages, although the studies did not address this in the tumor microenvironment. Nevertheless, this opens up the possibility that regular exercise training may exert a protective innate immune effect against breast cancer, potentially by inducing a cancer-suppressing phenotype of TAMs. This review will describe potential mechanisms through which exercise may modulate the behavior of TAMs.


Assuntos
Neoplasias da Mama/imunologia , Neoplasias da Mama/prevenção & controle , Exercício Físico/fisiologia , Macrófagos/imunologia , Microambiente Tumoral/imunologia , Feminino , Humanos , Imunidade Inata , Macrófagos/patologia
16.
Eur Rev Aging Phys Act ; 19(1): 15, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35725379

RESUMO

BACKGROUND: Aging leads to a number of structural and physiological deficits such as loss of muscle mass and strength. Strength training at ~ 70% of 1 repetition max (RM) is recommended to prevent age-related loss of muscle mass and strength. However, most older adults may not be able to perform 70% of 1RM or higher intensity. An alternative exercise training program combining low intensity resistance exercise with blood flow restriction (BFR) can result in similar acute and chronic benefits to skeletal muscles in older adults. MAIN BODY AND SHORT CONCLUSION: The potential mechanisms involved are discussed, and include reactive hyperaemia, metabolic stress, and hypoxia. Key issues and safety with the use of BFR in older adults, especially those with chronic conditions are also discussed. Although there has been no reported evidence to suggest that BFR elevates the risk of clinical complications any more than high intensity exercise, it is recommended for individuals to be medically cleared of any cardiovascular risks, prior to engaging in BFR exercise.

17.
J Immunother Cancer ; 10(9)2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36180069

RESUMO

Despite accumulating evidence that supports the beneficial effects of physical exercise in inhibiting cancer progression, whether exercise modulates its effects through systemic and cellular changes in iron metabolism and immune-tumor crosstalk is unknown. Cancer cells have greater metabolic requirements than normal cells, with their survival and proliferation depending largely on iron bioavailability. Although iron is an essential mineral for mitogenesis, it also participates in a form of iron-dependent programmed cell death termed ferroptosis. In this short hypothesis paper, we speculate that modulating iron bioavailability, transport and metabolism with regular exercise can have significant implications for tumor and stromal cells in the tumor microenvironment, by affecting multiple tumor-autonomous and stromal cell responses.


Assuntos
Neoplasias , Microambiente Tumoral , Exercício Físico , Humanos , Imunoterapia , Ferro/metabolismo , Neoplasias/patologia
18.
Trends Endocrinol Metab ; 33(2): 136-146, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34952764

RESUMO

Alpha-ketoglutarate (AKG) is an intermediate in the Krebs cycle involved in various metabolic and cellular pathways. As an antioxidant, AKG interferes in nitrogen and ammonia balance, and affects epigenetic and immune regulation. These pleiotropic functions of AKG suggest it may also extend human healthspan. Recent studies in worms and mice support this concept. A few studies published in the 1980s and 1990s in humans suggested the potential benefits of AKG in muscle growth, wound healing, and in promoting faster recovery after surgery. So far there are no recently published studies demonstrating the role of AKG in treating aging and age-related diseases; hence, further clinical studies are required to better understand the role of AKG in humans. This review will discuss the regulatory role of AKG in aging, as well as its potential therapeutic use in humans to treat age-related diseases.


Assuntos
Antioxidantes , Ácidos Cetoglutáricos , Animais , Antioxidantes/metabolismo , Ciclo do Ácido Cítrico , Suplementos Nutricionais , Humanos , Ácidos Cetoglutáricos/metabolismo , Ácidos Cetoglutáricos/uso terapêutico , Camundongos
19.
Front Med (Lausanne) ; 9: 962101, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35979209

RESUMO

Background: Since the outbreak of COVID-19 pandemic the interindividual variability in the course of the disease has been reported, indicating a wide range of factors influencing it. Factors which were the most often associated with increased COVID-19 severity include higher age, obesity and diabetes. The influence of cytokine storm is complex, reflecting the complexity of the immunological processes triggered by SARS-CoV-2 infection. A modern challenge such as a worldwide pandemic requires modern solutions, which in this case is harnessing the machine learning for the purpose of analysing the differences in the clinical properties of the populations affected by the disease, followed by grading its significance, consequently leading to creation of tool applicable for assessing the individual risk of SARS-CoV-2 infection. Methods: Biochemical and morphological parameters values of 5,000 patients (Curisin Healthcare (India) were gathered and used for calculation of eGFR, SII index and N/L ratio. Spearman's rank correlation coefficient formula was used for assessment of correlations between each of the features in the population and the presence of the SARS-CoV-2 infection. Feature importance was evaluated by fitting a Random Forest machine learning model to the data and examining their predictive value. Its accuracy was measured as the F1 Score. Results: The parameters which showed the highest correlation coefficient were age, random serum glucose, serum urea, gender and serum cholesterol, whereas the highest inverse correlation coefficient was assessed for alanine transaminase, red blood cells count and serum creatinine. The accuracy of created model for differentiating positive from negative SARS-CoV-2 cases was 97%. Features of highest importance were age, alanine transaminase, random serum glucose and red blood cells count. Conclusion: The current analysis indicates a number of parameters available for a routine screening in clinical setting. It also presents a tool created on the basis of these parameters, useful for assessing the individual risk of developing COVID-19 in patients. The limitation of the study is the demographic specificity of the studied population, which might restrict its general applicability.

20.
J Gerontol A Biol Sci Med Sci ; 77(10): 1959-1968, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-35661882

RESUMO

Low skeletal muscle mass is associated with cognitive impairment and dementia in older adults. This review describes the possible underlying pathophysiological mechanisms: systemic inflammation, insulin metabolism, protein metabolism, and mitochondrial function. We hypothesize that the central tenet in this pathophysiology is the dysfunctional myokine secretion consequent to minimal physical activity. Myokines, such as fibronectin type III domain containing 5/irisin and cathepsin B, are released by physically active muscle and cross the blood-brain barrier. These myokines upregulate local neurotrophin expression such as brain-derived neurotrophic factor (BDNF) in the brain microenvironment. BDNF exerts anti-inflammatory effects that may be responsible for neuroprotection. Altered myokine secretion due to physical inactivity exacerbates inflammation and impairs muscle glucose metabolism, potentially affecting the transport of insulin across the blood-brain barrier. Our working model also suggests other underlying mechanisms. A negative systemic protein balance, commonly observed in older adults, contributes to low skeletal muscle mass and may also reflect deficient protein metabolism in brain tissues. As a result of age-related loss in skeletal muscle mass, decrease in the abundance of mitochondria and detriments in their function lead to a decrease in tissue oxidative capacity. Dysfunctional mitochondria in skeletal muscle and brain result in the excessive production of reactive oxygen species, which drives tissue oxidative stress and further perpetuates the dysfunction in mitochondria. Both oxidative stress and accumulation of mitochondrial DNA mutations due to aging drive cellular senescence. A targeted approach in the pathophysiology of low muscle mass and cognition could be to restore myokine balance by physical activity.


Assuntos
Cognição , Músculo Esquelético , Idoso , Anti-Inflamatórios , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Catepsina B/metabolismo , DNA Mitocondrial/metabolismo , Fibronectinas/metabolismo , Glucose/metabolismo , Humanos , Inflamação/metabolismo , Insulinas/metabolismo , Músculo Esquelético/metabolismo , Espécies Reativas de Oxigênio/metabolismo
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