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1.
J Interprof Care ; 38(5): 893-906, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39045867

RESUMO

Increasing chronic disease rates in regional Australian communities necessitates innovative models of healthcare. We evaluated the efficacy of an interprofessional chronic disease program, delivered within a regional student-led nursing and allied health clinic in Southern Queensland, Australia. Changes to anthropometric, aerobic fitness and strength, and quality of life outcomes were examined at four time points spanning 16 months: intake, program transition (4 months), 6 and 12 months (post-transition). Our primary aim was to investigate whether the health improvements achieved during the program were sustained at 12 months in a subset of participants who provided complete data. Significant improvements were found in 6 of 11 measures, including the 6-minute walk test, grip strength, and self-reported quality of life across physical and psychosocial dimensions, with these improvements maintained to final review. No significant changes were found in body mass index (BMI), waist circumference, fat mass, or muscle mass. This is the first health clinic in regional Australia to deliver a student-led model of interprofessional and collaborative service to tackle the increasing burden of chronic disease in the community. The cost-effectiveness of this service and other potential clinical and social benefits remain to be investigated.


Assuntos
Qualidade de Vida , Humanos , Doença Crônica/prevenção & controle , Doença Crônica/terapia , Feminino , Masculino , Pessoa de Meia-Idade , Queensland , Adulto , Relações Interprofissionais , Idoso , Comportamento Cooperativo , Equipe de Assistência ao Paciente/organização & administração , Índice de Massa Corporal , Aptidão Física
2.
Int J Sports Med ; 44(7): 484-495, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37084758

RESUMO

Traditional continuous training and high-intensity interval training (HIIT) can increase maximal oxygen uptake (V̇O2max). However, there is conflicting evidence regarding which form of training demonstrates the greatest improvements to V̇O2max, and data in women is sparse. We conducted a systematic review and meta-analyses to assess whether moderate to vigorous-intensity continuous training (MVICT) or HIIT was superior at improving V̇O2max in women. Randomised controlled and parallel studies examined the influence of MVICT and/or HIIT on V̇O2max in women. There was no statistical difference in V̇O2max improvements after training between women in the MVICT and HIIT cohorts (mean difference [MD]: -0.42, 95%CI: -1.43 to 0.60, p>0.05). Both MVICT and HIIT increased V̇O2max from baseline (MD: 3.20, 95% CI: 2.73 to 3.67 and MD: 3.16, 95% CI 2.09 to 4.24, respectively, p<0.001). Greater improvements in V̇O2max were observed in women who participated in more training sessions in both training formats. Long-HIIT was superior to short-HIIT protocols at increasing V̇O2max. Although MVICT and long-HIIT sessions elicited greater increases in V̇O2max in younger women compared to short-HIIT protocols, these differences were negligible in older women. Our findings suggest MVICT and HIIT are equally effective strategies for improving V̇O2max and indicate an effect of age on its response to training in women.


Assuntos
Treinamento Intervalado de Alta Intensidade , Consumo de Oxigênio , Humanos , Feminino , Idoso , Consumo de Oxigênio/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos
3.
Pflugers Arch ; 474(11): 1159-1169, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36085194

RESUMO

Ageing causes a gradual deterioration of bodily functions and telomere degradation. Excessive telomere shortening leads to cellular senescence and decreases tissue vitality. Six proteins, called shelterin, protect telomere integrity and control telomere length through telomerase-dependent mechanisms. Exercise training appears to maintain telomeres in certain somatic cells, although the underlying molecular mechanisms are incompletely understood. Here, we examined the influence of a single bout of vigorous exercise training on leukocyte telomerase reverse transcriptase (TERT) and shelterin gene expression, and the abundance of three microRNAs (miRNAs) implicated in biological ageing (miRNA-143, -223 and -486-5p) in an elite athlete and large animal model, Thoroughbred horses. Gene and miRNA expression were analysed using primer-based and TaqMan Assay qPCR. Leukocyte TRF1, TRF2 and POT1 expression were all significantly increased whilst miR-223 and miR-486-5p were decreased immediately after vigorous exercise (all p < 0.05), and tended to return to baseline levels 24 h after training. Relative to the young horses (~ 3.9 years old), middle-aged horses (~ 14.8 years old) exhibited reduced leukocyte TERT gene expression, and increased POT1 and miR-223 abundance (all p < 0.05). These data demonstrate that genes transcribing key components of the shelterin-telomere complex are influenced by ageing and dynamically regulated by a single bout of vigorous exercise in a large, athletic mammal - Thoroughbred horses. Our findings also implicate TERT and shelterin gene transcripts as potential targets of miR-223 and miR-486-5p, which are modulated by exercise and may have a role in the telomere maintenance and genomic stability associated with long-term aerobic training.


Assuntos
MicroRNAs , Telomerase , Envelhecimento/genética , Animais , Cavalos/genética , Mamíferos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Complexo Shelterina , Telomerase/genética , Telomerase/metabolismo , Telômero/genética , Telômero/metabolismo
4.
Am J Physiol Endocrinol Metab ; 319(2): E320-E329, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32603601

RESUMO

Complex organisms rely heavily on intercellular communication. The rapidly expanding field of extracellular vesicle biology has made it clear that the necessary intercellular communication occurs partly through their paracrine and endocrine actions. Extracellular vesicles are nanoscale lipid membranes (30-2,000 nm in diameter) that shuttle functional biological material between cells. They are released from numerous tissues and are isolated from nearly all biofluids and cell cultures. Although their biogenesis, cell targeting, and functional roles are incompletely understood, they appear to have crucial roles in physiological and disease processes. Their enormous potential to serve as sensitive biomarkers of disease and also new therapeutic interventions for diseases have gained them considerable attention in recent years. Regular physical exercise training confers systemic health benefits and consequently prevents many age-related degenerative diseases. Many of the molecular mechanisms responsible for the salubrious effects of exercise are known, yet a common underlying mechanism potentially responsible for the holistic health benefits of exercise has only recently been explored (i.e., via extracellular vesicle transport of biological material). Here, we provide an overview of extracellular vesicle biology before outlining the current evidence on the capacity for a single bout and chronic exercise to elicit changes in extracellular vesicle content and modulate their molecular cargo (e.g., small RNAs). We highlight areas for future research and emphasize their potential utility as biomarkers and therapeutic strategies of disease and its prevention.


Assuntos
Comunicação Celular/fisiologia , Exercício Físico/fisiologia , Espaço Extracelular/fisiologia , Vesículas Extracelulares/fisiologia , Animais , Vesículas Extracelulares/química , Promoção da Saúde , Cardiopatias/prevenção & controle , Humanos , MicroRNAs/fisiologia , Condicionamento Físico Animal/fisiologia , Prevenção Primária/métodos
5.
J Strength Cond Res ; 34(12): 3489-3497, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28930880

RESUMO

Denham, J, Scott-Hamilton, J, Hagstrom, AD, and Gray, AJ. Cycling power outputs predict functional threshold power and maximum oxygen uptake. J Strength Cond Res 34(12): 3489-3497, 2020-Functional threshold power (FTP) has emerged as a correlate of lactate threshold and is commonly assessed by recreational and professional cyclists for tailored exercise programing. To identify whether results from traditional aerobic and anaerobic cycling tests could predict FTP and V[Combining Dot Above]O2max, we analyzed the association between estimated FTP, maximum oxygen uptake (V[Combining Dot Above]O2max [ml·kg·min]) and power outputs obtained from a maximal cycle ergometry cardiopulmonary exercise test (CPET), and a 30-second Wingate test in a heterogeneous cohort of cycle-trained and untrained individuals (N = 40, mean ± SD; age: 32.6 ± 10.6 years; relative V[Combining Dot Above]O2max: 46.8 ± 9.1 ml·kg·min). The accuracy and sensitivity of the prediction equations were also assessed in young men (N = 11) before and after a 6-week sprint interval training intervention. Moderate-to-strong positive correlations were observed between FTP, relative V[Combining Dot Above]O2max, and power outputs achieved during incremental and 30-second Wingate cycling tests (r = 0.39-0.965, all p ≤ .05). Whilst maximum power achieved during incremental cycle testing (Pmax) and relative V[Combining Dot Above]O2max were predictors of FTP (r = 0.93), age and FTP (W·kg) estimated relative V[Combining Dot Above]O2max (r = 0.80). Our findings confirm that FTP predominantly relies on aerobic metabolism and indicate that both prediction models are sensitive enough to detect meaningful exercise-induced changes in FTP and V[Combining Dot Above]O2max. Thus, coaches should consider limiting the time and load demands placed on athletes by conducting a maximal cycle ergometry CPET to estimate FTP. In addition, a 20-minute FTP test is a convenient method to assess V[Combining Dot Above]O2max and is particularly relevant for exercise professionals without access to expensive CPET equipment.


Assuntos
Consumo de Oxigênio , Oxigênio , Adulto , Ergometria , Exercício Físico , Teste de Esforço , Humanos , Masculino , Adulto Jovem
6.
Int J Sports Med ; 39(6): 482-489, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29698983

RESUMO

Accounting for one in three cancer diagnoses, breast cancer is the second most commonly diagnosed cancer in women. Exercise has a well-accepted role in the multi-disciplinary approach to rehabilitating breast cancer survivors. Despite the many known benefits of resistance training on women recovering from breast cancer, the molecular mechanisms are poorly understood. MicroRNAs are small non-coding RNAs that have crucial roles in growth and development. Here, we analysed the abundance of 9 miRNAs, with known roles in muscle physiology and some linked to cancer, in serum samples from 24 breast cancer survivors before and after a 16-week resistance training or usual care intervention. The resistance training group completed supervised thrice-weekly training. miRNA abundance was assessed before and after the intervention period using qPCR. There were no statistically significant changes in any of the miRNAs between groups after the intervention period (all p>0.05). After assessing miRNA abundance in context with high and low responders to resistance training, we observed that relative to low responders, high responders exhibited increased miR-133a-3p and a borderline statistically significant increase in miR-370-3p. Findings from our controlled study indicate the diverse interindividual miRNA responses to resistance training and reveal a discordant regulation between high and low responders.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , MicroRNAs/sangue , Treinamento Resistido , Feminino , Humanos , Pessoa de Meia-Idade , Força Muscular/fisiologia , Treinamento Resistido/métodos
7.
Int J Sports Med ; 39(1): 67-72, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29126336

RESUMO

Small non-coding RNAs, such as microRNAs (miRNAs), have emerged as powerful post-transcriptional regulators of gene expression that play important roles in many developmental and biological processes. In this study, we assessed the abundance of circulating microRNAs important for skeletal muscle and heart adaptations to exercise (miR-1, miR-133a, miR-133b and miR-486), following acute exercise and short-term sprint interval training (SIT). Twenty-eight individuals completed four all-out efforts on a cycle ergometer, and donated blood before and 30 min after the cessation of exercise. A subset of 10 untrained men completed 4-6 efforts of SIT, three times a week for 6 weeks, and donated resting blood samples before and after the intervention. MiRNA TaqMan qPCR was performed and whilst no changes were observed after a single session of SIT (all p>0.05), the 6-wk SIT intervention significantly reduced the whole blood content of all four miRNAs (mean fold-changes: 0.37-0.48, all p<0.01). Our data suggests that circulating miRNAs are responsive to short-term SIT and could have roles in SIT-induced health and performance adaptations. Further work is required to establish whether circulating miRNAs could serve as biomarkers for predicting exercise training responses and monitoring exercise interventions.


Assuntos
MicroRNA Circulante/sangue , Treinamento Intervalado de Alta Intensidade/métodos , Desenvolvimento Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto , Biomarcadores/sangue , Humanos , Masculino , Consumo de Oxigênio/fisiologia
8.
Eur J Appl Physiol ; 116(6): 1245-53, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27155847

RESUMO

PURPOSE: Regular engagement in resistance exercise training elicits many health benefits including improvement to muscular strength, hypertrophy and insulin sensitivity, though the underpinning molecular mechanisms are poorly understood. The purpose of this study was to determine the influence 8 weeks of resistance exercise training has on leukocyte genome-wide DNA methylation and gene expression in healthy young men. METHODS: Eight young (21.1 ± 2.2 years) men completed one repetition maximum (1RM) testing before completing 8 weeks of supervised, thrice-weekly resistance exercise training comprising three sets of 8-12 repetitions with a load equivalent to 80 % of 1RM. Blood samples were collected at rest before and after the 8-week training intervention. Genome-wide DNA methylation and gene expression were assessed on isolated leukocyte DNA and RNA using the 450K BeadChip and HumanHT-12 v4 Expression BeadChip (Illumina), respectively. RESULTS: Resistance exercise training significantly improved upper and lower body strength concurrently with diverse genome-wide DNA methylation and gene expression changes (p ≤ 0. 01). DNA methylation changes occurred at multiple regions throughout the genome in context with genes and CpG islands, and in genes relating to axon guidance, diabetes and immune pathways. There were multiple genes with increased expression that were enriched for RNA processing and developmental proteins. Growth factor genes-GHRH and FGF1-showed differential methylation and mRNA expression changes after resistance training. CONCLUSIONS: Our findings indicate that resistance exercise training improves muscular strength and is associated with reprogramming of the leukocyte DNA methylome and transcriptome.


Assuntos
DNA/genética , Epigênese Genética/fisiologia , Leucócitos/fisiologia , Força Muscular/genética , Treinamento Resistido/métodos , Transcriptoma/genética , Adaptação Fisiológica/genética , Metilação de DNA/genética , Regulação da Expressão Gênica/genética , Humanos , Masculino , Adulto Jovem
9.
Eur J Appl Physiol ; 116(8): 1537-44, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27278522

RESUMO

PURPOSE: Endurance exercise improves cardiovascular health and reduces mortality risk. Augmentation index (AIx) reflects adverse loading exerted on the heart and large arteries and predicts future cardiovascular disease. The purpose of this study was to establish whether endurance athletes possess lower AIx and aortic blood pressure compared to healthy controls, and to determine the association between AIx and cardiorespiratory fitness. METHODS: Forty-six endurance athletes and 43 healthy controls underwent central BP and AIx measurements by non-invasive applanation tonometry before a maximal exercise test. Peak oxygen uptake ([Formula: see text]) was assessed by pulmonary analysis. RESULTS: Relative to controls, athletes had significantly lower brachial diastolic blood pressure (BP, -4.8 mmHg, p < 0.01), central systolic BP (-3.5 mmHg, p = 0.07), and AIx at a heart rate of 75 beats min(-1) (AIx@75, -11.9 %, p < 0.001). No AIx@75 differences were observed between athletes and controls when adjusted for age and [Formula: see text] [athletes vs controls mean (%) ± SE: -6.9 ± 2.2 vs -5.7 ± 2.3, p = 0.76]. Relative to men with low [Formula: see text], those with moderate and high [Formula: see text] had lower age-adjusted AIx@75 (p < 0.001). In women, those with high [Formula: see text] had lower AIx@75 than those with low and moderate [Formula: see text] (p < 0.01). CONCLUSIONS: The lower AIx@75 in endurance athletes is partly mediated by [Formula: see text]. While an inverse relationship between AIx@75 and [Formula: see text] was found in men, women with the highest [Formula: see text] possessed lowest AIx@75 compared to females with moderate or poor cardiorespiratory fitness. We recommend aerobic training aimed at achieving a minimum [Formula: see text] of 45 ml kg(-1) min(-1) to decrease the risk of future cardiovascular events and all-cause mortality.


Assuntos
Aorta/fisiologia , Pressão Arterial/fisiologia , Aptidão Cardiorrespiratória/fisiologia , Resistência Física/fisiologia , Esportes/fisiologia , Rigidez Vascular/fisiologia , Adolescente , Adulto , Desempenho Atlético/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
10.
J Strength Cond Res ; 29(8): 2137-41, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25647646

RESUMO

Sprint interval training (SIT) rapidly improves cardiorespiratory fitness but demands less training time and volume than traditional endurance training. Although the health and fitness benefits caused by SIT have received considerable research focus, the effect of short-term SIT on 5-km run performance is unknown. Thirty healthy untrained participants (aged 18-25 years) were allocated to a control (n = 10) or a SIT (n = 20) group. Sprint interval training involved 3-8 sprints at maximal intensity, 3 times a week for 4 weeks. Sprints were progressed to 8 by the 12th session. All participants completed a 5-km time trial on a public running track and an incremental treadmill test in an exercise physiology laboratory to determine 5-km run performance and maximum oxygen uptake, respectively, before and after the 4-week intervention. Relative to the controls, sprint interval-trained participants improved 5-km run performance by 4.5% (p < 0.001), and this was accompanied by improvements in absolute and relative maximum oxygen uptake (4.9%, p = 0.04 and 4.5%, p = 0.045, respectively). Therefore, short-term SIT significantly improves 5-km run performance in untrained young men. We believe that SIT is a time-efficient means of improving cardiorespiratory fitness and 5-km endurance performance.


Assuntos
Desempenho Atlético/fisiologia , Condicionamento Físico Humano/métodos , Condicionamento Físico Humano/fisiologia , Corrida/fisiologia , Adolescente , Adulto , Teste de Esforço , Humanos , Masculino , Consumo de Oxigênio , Aptidão Física/fisiologia , Adulto Jovem
11.
J Hypertens ; 42(2): 197-204, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37851002

RESUMO

The acute and long-term benefits of exercise on cardiovascular health are well established, yet the optimal mode of exercise training that improves arterial stiffness in women with high blood pressure remains unclear. The aim of this systematic review and meta-analysis was to assess the influence of aerobic and resistance training on arterial stiffness in women with high blood pressure. After an extensive search of four online databases, six randomized controlled trials met the inclusion criteria and were included in meta-analyses. Data were extracted from six studies examining the influence of exercise on arterial stiffness assessed by pulse wave velocity (PWV) and were expressed as standardized mean difference (SMD). Whereas aerobic exercise significantly reduced arterial PWV in women with high blood pressure after long-term training [SMD -1.87, 95% confidence interval (CI) -2.34 to -1.40], resistance training had a more modest effect that was borderline statistically significant (SMD -0.31, 95% CI -0.65 to 0.03). These findings suggest regular long-term aerobic exercise training (i.e. 12-20 week interventions) reduces arterial stiffness in women with high blood pressure. Although not statistically significant, the modest number of included trials and lack of publication bias encourages further assessments on the efficacy of resistance exercise for improving arterial stiffness in women with high blood pressure. Given the unique benefits of aerobic and resistance training, particularly for postmenopausal women (e.g. bone health and muscular strength), both modes of training should be encouraged for women with high blood pressure to enhance arterial function and support favorable cardiovascular outcomes.


Assuntos
Hipertensão , Treinamento Resistido , Rigidez Vascular , Humanos , Feminino , Rigidez Vascular/fisiologia , Análise de Onda de Pulso , Exercício Físico/fisiologia , Pressão Sanguínea
12.
Aging Cell ; 22(6): e13836, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37041671

RESUMO

Telomerase preserves genomic integrity by maintaining and protecting the telomeres. Seminal findings from 1985 revealed the canonical role of telomerase and motivated investigations into potential therapeutic strategies to combat one of the hallmarks of ageing-telomere attrition. Since then, the field of telomere biology has rapidly expanded, with telomerase serving essential roles in cancer and cell development through its canonical function. However, telomerase also exerts critical extra-telomeric functions through its protein (telomerase reverse transcriptase, TERT) and RNA components (telomerase RNA component, TERC). Telomerase re-activation or ectopic expression promotes survival and permits unlimited proliferation in tumours and healthy non-malignant cells. TERT gene therapies improve health and lifespan in ageing mice and mouse models of age-related diseases. The extra-telomeric functions of telomerase are critical to ageing. These include protection against oxidative stress, orchestration of chromatin modifications and transcription, and regulation of angiogenesis and metabolism (e.g. mitochondrial function and glucose control). Given these biological functions are key adaptations to endurance training and the recent meta-analytical findings that indicate exercise up-regulates TERT and telomerase, a comprehensive discussion on the implications of the canonical and extra-telomeric roles of telomerase is warranted. This review highlights the therapeutic benefits of telomerase-based treatments for idiopathic and chronic diseases that are linked to ageing. Discussion on the canonical and extra-telomeric roles of telomerase are presented, followed by a detailed summary of the evidence on how exercise influences telomerase. Finally, the potential cell signalling underpinning the exercise-induced modulation of telomerase are discussed with directions for future research.


Assuntos
Treino Aeróbico , Envelhecimento Saudável , Telomerase , Humanos , Animais , Camundongos , Telomerase/genética , Telomerase/metabolismo , Envelhecimento Saudável/genética , Envelhecimento/genética , Envelhecimento/metabolismo , Telômero/metabolismo
13.
Animals (Basel) ; 13(17)2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37685063

RESUMO

This paper provides a comprehensive discussion on the physiological impacts of hypoxic training, its benefits to endurance performance, and a rationale for utilizing it to improve performance in the equine athlete. All exercise-induced training adaptations are governed by genetics. Exercise prescriptions can be tailored to elicit the desired physiological adaptations. Although the application of hypoxic stimuli on its own is not ideal to promote favorable molecular responses, exercise training under hypoxic conditions provides an optimal environment for maximizing physiological adaptations to enhance endurance performance. The combination of exercise training and hypoxia increases the activity of the hypoxia-inducible factor (HIF) pathway compared to training under normoxic conditions. Hypoxia-inducible factor-1 alpha (HIF-1α) is known as a master regulator of the expression of genes since over 100 genes are responsive to HIF-1α. For instance, HIF-1-inducible genes include those critical to erythropoiesis, angiogenesis, glucose metabolism, mitochondrial biogenesis, and glucose transport, all of which are intergral in physiological adaptations for endurance performance. Further, hypoxic training could conceivably have a role in equine rehabilitation when high-impact training is contraindicated but a quality training stimulus is desired. This is achievable through purpose-built equine motorized treadmills inside commercial hypoxic chambers.

14.
Sports (Basel) ; 11(9)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37755860

RESUMO

Coconut water is used as an alternative to conventional sports drinks for hydration during endurance cycling; however, evidence supporting its use is limited. This study determined if drinking coconut water compared to a sports drink altered cycling performance and physiology. In a randomized crossover trial, 19 experienced male (n = 15) and female (n = 4) cyclists (age 30 ± 9 years, body mass 79 ± 11 kg, V̇O2 peak 55 ± 8 mL·kg-1·min-1) completed two experimental trials, consuming either a commercially available sports drink or iso-calorific coconut water during 90 min of sub-maximal cycling at 70% of their peak power output, followed by a simulated, variable gradient, 20 km time trial. Blood glucose, lactate, sweat loss, and heart rate were monitored throughout the 90 min of sub-maximal cycling, as well as the time trial performance (seconds) and average power (watts). A repeated measures analysis of variance and effect sizes (Cohen's d) analysis were applied. There were no significant differences (p ≥ 0.05) between the treatments for any of the measured physiological or performance variables. Additionally, the effect size analysis showed only trivial (d ≤ 0.2) differences between the treatments for all the measured variables, except blood glucose, which was lower in the coconut water trial compared to the sports drink trial (d = 0.31). Consuming coconut water had a similar effect on the cycling time trial performance and the physiological responses to consuming a commercially available sports drink.

15.
Ageing Res Rev ; 70: 101411, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34284150

RESUMO

Telomeres protect genomic stability and shortening is one of the hallmarks of ageing. Telomerase reverse transcriptase (TERT) is the major protein component of telomerase, which elongates telomeres. Given that short telomeres are linked to a host of chronic diseases and the therapeutic potential of telomerase-based therapies as treatments and a strategy to extend lifespan, lifestyle factors that increase TERT gene expression and telomerase activity could attenuate telomere attrition and contribute to healthy biological ageing. Physical activity and maximal aerobic fitness are associated with telomere maintenance, yet the molecular mechanisms remain unclear. Therefore, the purpose of this systematic review and meta-analysis was to identify the influence of a single bout of exercise and long-term exercise training on TERT expression and telomerase activity. A search of human and rodent trials using the PubMed, Scopus, Science Direct and Embase databases was performed. Based on findings from the identified and eligible trials, both a single bout of exercise (n; standardised mean difference [95%CI]: 5; SMD: 1.19 [0.41-1.97], p = 0.003) and long-term exercise training (10; 0.31 [0.03-0.60], p = 0.03) up-regulates TERT and telomerase activity in non-cancerous somatic cells. As human and rodent studies were included in the meta-analyses both exhibited heterogeneity (I2 = 55-87%, p < 0.05). Endurance athletes also exhibited increased leukocyte TERT and telomerase activity compared to their inactive counterparts. These findings suggest exercise training as an inexpensive lifestyle factor that increases TERT expression and telomerase activity. Regular exercise training could attenuate telomere attrition through a telomerase-dependent mechanism and ultimately extend health-span and longevity.


Assuntos
Telomerase , Exercício Físico , Expressão Gênica , Telomerase/genética , Telomerase/metabolismo , Telômero/metabolismo , Encurtamento do Telômero
16.
Front Genet ; 12: 652497, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421981

RESUMO

Exercise training is one of the few therapeutic interventions that improves health span by delaying the onset of age-related diseases and preventing early death. The length of telomeres, the 5'-TTAGGG n -3' tandem repeats at the ends of mammalian chromosomes, is one of the main indicators of biological age. Telomeres undergo shortening with each cellular division. This subsequently leads to alterations in the expression of several genes that encode vital proteins with critical functions in many tissues throughout the body, and ultimately impacts cardiovascular, immune and muscle physiology. The sub-telomeric DNA is comprised of heavily methylated, heterochromatin. Methylation and histone acetylation are two of the most well-studied examples of the epigenetic modifications that occur on histone proteins. DNA methylation is the type of epigenetic modification that alters gene expression without modifying gene sequence. Although diet, genetic predisposition and a healthy lifestyle seem to alter DNA methylation and telomere length (TL), recent evidence suggests that training status or physical fitness are some of the major factors that control DNA structural modifications. In fact, TL is positively associated with cardiorespiratory fitness, physical activity level (sedentary, active, moderately trained, or elite) and training intensity, but is shorter in over-trained athletes. Similarly, somatic cells are vulnerable to exercise-induced epigenetic modification, including DNA methylation. Exercise-training load, however, depends on intensity and volume (duration and frequency). Training load-dependent responses in genomic profiles could underpin the discordant physiological and physical responses to exercise. In the current review, we will discuss the role of various forms of exercise training in the regulation of DNA damage, TL and DNA methylation status in humans, to provide an update on the influence exercise training has on biological aging.

17.
Equine Vet J ; 53(3): 431-450, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32671871

RESUMO

Horses (Equus ferus caballus) have evolved over the past 300 years in response to man-made selection for particular athletic traits. Some of the selected traits were selected based on the size and horses' muscular power (eg Clydesdales), whereas other breeds were bred for peak running performance (eg Thoroughbred and Arabian). Although the physiological changes and some of the cellular adaptations responsible for athletic potential of horses have been identified, the molecular mechanisms are only just beginning to be comprehensively investigated. The purpose of this review was to outline and discuss the current understanding of the molecular mechanisms underpinning the athletic performance and cardiorespiratory fitness in athletic breeds of horses. A brief review of the biology of epigenetics is provided, including discussion on DNA methylation, histone modifications and small RNAs, followed by a summary and critical review of the current work on the exercise-induced epigenetic and transcriptional changes in horses. Important unanswered questions and currently unexplored areas that deserve attention are highlighted. Finally, a rationale for the analysis of epigenetic modifications in the context with exercise-related traits and ailments associated with athletic breeds of horses is outlined in order to help guide future research.


Assuntos
Adaptação Fisiológica , Corrida , Adaptação Fisiológica/genética , Animais , Atletas , Epigênese Genética , Cavalos/genética , Humanos
18.
Mech Ageing Dev ; 199: 111552, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34363832

RESUMO

Exercise training seems to promote healthy biological ageing partly by inducing telomere maintenance, yet the molecular mechanisms are not fully understood. Recent studies have emphasised the importance of microRNAs (miRNAs) in ageing and their ability to mirror pathophysiological alterations associated with age-related diseases. We examined the association between aerobic fitness and leukocyte telomere length before determining the influence of vigorous exercise training on the regulation of leukocyte miRNA networks. Telomere length was positively correlated to aerobic fitness (r = 0.32, p = 0.02). 104 miRNAs were differentially expressed after six weeks of thrice-weekly sprint interval training (SIT) in healthy men (q < 0.05). Gene co-expression analysis (WGCNA) detected biologically meaningful miRNA networks, five of which were significantly correlated with pre-SIT and post-SIT expression profiles (p < 0.001) and telomere length. Enrichment analysis revealed that the immune response, T cell differentiation and lipid metabolism associated miRNAs clusters were significantly down-regulated after SIT. Using data acquired from the Gene Expression Omnibus (GEO), we also identified two co-expressed miRNAs families that were modulated by exercise training in previous investigations. Collectively, our findings highlight the miRNA networks implicated in exercise adaptations and telomere regulation, and suggest that SIT may attenuate biological ageing through the control of the let-7 and miR-320 miRNA families.


Assuntos
Envelhecimento/fisiologia , Exercício Físico/genética , Treinamento Intervalado de Alta Intensidade/métodos , Leucócitos/fisiologia , MicroRNAs/fisiologia , Aptidão Física/fisiologia , Homeostase do Telômero/fisiologia , Adulto , Feminino , Perfilação da Expressão Gênica/métodos , Envelhecimento Saudável/genética , Humanos , Masculino , MicroRNAs/genética , Sequências Reguladoras de Ácido Ribonucleico/fisiologia , Transdução de Sinais
19.
Sci Rep ; 11(1): 4056, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33603000

RESUMO

Amongst other immune cells, neutrophils play a key role in systemic inflammation leading to cardiovascular disease and can release inflammatory factors, including lipocalin-2 (LCN2). LCN2 drives cardiac hypertrophy and plays a role in maladaptive remodelling of the heart and has been associated with renal injury. While lifestyle factors such as diet and exercise are known to attenuate low-grade inflammation, their ability to modulate plasma LCN2 levels is unknown. Forty-eight endurance athletes and 52 controls (18-55 years) underwent measurement for various cardiovascular health indicators, along with plasma LCN2 concentration. No significant difference in LCN2 concentration was seen between the two groups. LCN2 was a very weak predictor or absent from models describing blood pressures or predicting athlete status. In another cohort, 57 non-diabetic overweight or obese men and post-menopausal women who fulfilled Adult Treatment Panel III metabolic syndrome criteria were randomly allocated into either a control, modified Dietary Approaches to Stop Hypertension (DASH) diet, or DASH and exercise group. Pre- and post-intervention demographic, cardiovascular health indicators, and plasma LCN2 expression were measured in each individual. While BMI fell in intervention groups, LCN2 levels remained unchanged within and between all groups, as illustrated by strong correlations between LCN2 concentrations pre- and 12 weeks post-intervention (r = 0.743, P < 0.0001). This suggests that circulating LCN2 expression are stable over a period of at least 12 weeks and is not modifiable by diet and exercise.


Assuntos
Dieta Redutora , Exercício Físico/fisiologia , Lipocalina-2/sangue , Adulto , Atletas , Feminino , Humanos , Lipocalina-2/metabolismo , Masculino
20.
J Equine Vet Sci ; 95: 103281, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33276931

RESUMO

Sodium bicarbonate administration in the hours prior to exercise has been used as a performance-enhancing substance in horses since the late 1980s. Although sodium bicarbonate administration to racehorses 24 hours before racing is a banned practice in most racing industries, whether or not it improves running performance in racehorses is currently unclear. The aim of this systematic review and meta-analysis was to establish whether or not acute sodium bicarbonate administration improves running performance in trained Standardbred and Thoroughbred horses. Seven randomized controlled trials, including eight experimental (exercise) trials and 74 horses, were included after a comprehensive search for relevant studies that met the inclusion criteria. Results indicated that sodium bicarbonate administration at 2.5-5 hours prior to a standardized treadmill test to exhaustion or simulated race (time-trial) does not influence running performance (number of horses, the overall effect [95% CI]: 32, -0.13 [-0.64 to 0.37] and 42, 0.01 [-0.42 to 0.44], respectively, both P > .05). The included studies demonstrated minimal heterogeneity (I2 = 0%-2%), low risks of bias according to the Cochrane Risk of Bias Tool and a lack of publication bias. On the basis of these findings, there is high-quality evidence to suggest that sodium bicarbonate administration does not improve running performance in trained Standardbred or Thoroughbred horses.


Assuntos
Doenças dos Cavalos , Condicionamento Físico Animal , Corrida , Animais , Teste de Esforço/veterinária , Cavalos , Bicarbonato de Sódio/farmacologia
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