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1.
J Clin Densitom ; 27(4): 101522, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39288472

RESUMEN

INTRODUCTION: Reliable peripheral quantitative computed tomography (pQCT) assessment is essential to the accurate longitudinal reporting of bone and muscle quality. However, the between-day reliability of pQCT and the influence of age on outcome reliability is currently unknown. OBJECTIVE: To quantify the same- and between-day reliability of morphological pQCT at proximal and distal segments of the forearm, shank, and thigh, and explore the influence of participant body size, age, and sex on outcome reliability. METHODS: Men and women (49 % female, 18-85 years, n=72-86) completed two consecutive-day pQCT testing sessions, where repeat measurements were conducted on day-one for technical error, and between-day for biological error quantification. Testing was undertaken following best practice body composition testing guidance, including standardized presentation and consistent time-of-day. RESULTS: All measurements of bone were classified as having 'good' to 'excellent' reliability [intraclass correlation coefficient (r=0.786- 0.999], as were measurements of muscle area (ICC r=0.991-0.999) and total fat (r=0.996-0.999). However, between- and same-day muscle density measurements at the thigh and forearm were classified as 'poor' (r=0.476) and 'moderate' (r=0.622), respectively. Likewise, intramuscular fat area at the thigh was classified as 'moderate' (r=0.737) for between-day measurement. Biological error was inflated compared to technical error by an average of 0.4 % for most measurements. Error values tended to increase proportionally with the amount of tissue quantified and males had significantly greater biological error for measurement of distal tibial bone (p<0.002) and trabecular area (p<0.002). Biological error was inflated among older adults for measurement of forearm muscle density (p<0.002). CONCLUSIONS: Most pQCT outcomes can be implemented with confidence, especially outcomes that assess bone area and density at any of the radial, tibial, and femoral sites investigated herein. However, it is important to account for the influence of biological measurement error in further studies, especially for muscle and intramuscular fat outcomes derived by pQCT.


Asunto(s)
Densidad Ósea , Músculo Esquelético , Tomografía Computarizada por Rayos X , Humanos , Masculino , Femenino , Anciano , Tomografía Computarizada por Rayos X/métodos , Persona de Mediana Edad , Anciano de 80 o más Años , Reproducibilidad de los Resultados , Adulto , Músculo Esquelético/diagnóstico por imagen , Adolescente , Adulto Joven , Antebrazo/diagnóstico por imagen , Muslo/diagnóstico por imagen , Factores de Edad , Factores Sexuales
2.
J Physiol ; 602(20): 5203-5215, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39303144

RESUMEN

Pre-clinical murine and in vitro models have demonstrated that exercise suppresses tumour and cancer cell growth. These anti-oncogenic effects of exercise were associated with the exercise-mediated release of myokines such as interleukin (IL)-15. However, no study has quantified the acute IL-15 response in human cancer survivors, and whether physiological adaptations to exercise training (i.e. body composition and cardiorespiratory fitness) influence this response. In the present study breast, prostate and colorectal cancer survivors (n = 14) completed a single bout of high-intensity interval exercise (HIIE) [4×4 min at 85-95% heart rate (HR) peak, 3 min at 50-70% HR peak] before and after 7 months of three times weekly high-intensity interval training (HIIT) on a cycle ergometer. At each time point venous blood was sampled before and immediately after HIIE to assess the acute myokine (IL-15, IL-6, IL-10, IL-1ra) responses. Markers of inflammation, cardiorespiratory fitness and measures of body composition were obtained at baseline and 7 months. An acute bout of HIIE resulted in a significant increase in IL-15 concentrations (pre-intervention: 113%; P = 0.013, post-intervention: 102%; P = 0.005). Post-exercise IL-15 concentrations were associated with all other post-exercise myokine concentrations, lean mass (P = 0.031), visceral adipose tissue (P = 0.039) and absolute V ̇ O 2 ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}}}$ peak (P = 0.032). There was no significant effect of 7 months of HIIT on pre- or post-HIIE IL-15 concentrations (P > 0.05). This study demonstrates HIIE is a sufficient stimulus to increase circulating IL-15 and other myokines including IL-6, IL-10 and IL-1ra which may be clinically relevant in the anti-oncogenic effect of exercise and repetitive exposure to these effects may contribute to the positive relationship between exercise and cancer recurrence. KEY POINTS: Exercise has been demonstrated to reduce the risk of cancer recurrence. Pre-clinical murine and in vitro models have demonstrated that exercise suppresses tumour and cancer cell growth, mediated by exercise-induced myokines (IL-6 and IL-15). High-intensity interval exercise significantly increased myokines associated with the anti-oncogenic effect of exercise and the magnitude of response was associated with lean mass, but training did not appear to influence this response. Given IL-15 has been implicated in the anti-oncogenic effect of exercise and is being explored as an immunotherapy agent, high-intensity interval exercise may improve outcomes for people living beyond cancer through IL-15-mediated pathways. Interventions that increase lean mass may also enhance this response.


Asunto(s)
Composición Corporal , Supervivientes de Cáncer , Entrenamiento de Intervalos de Alta Intensidad , Inflamación , Interleucina-15 , Humanos , Interleucina-15/sangre , Masculino , Femenino , Persona de Mediana Edad , Inflamación/fisiopatología , Inflamación/sangre , Entrenamiento de Intervalos de Alta Intensidad/métodos , Anciano , Capacidad Cardiovascular , Neoplasias de la Mama/sangre , Neoplasias de la Próstata/sangre , Ejercicio Físico/fisiología , Neoplasias
3.
Aging Dis ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-39012673

RESUMEN

Physical exercise may reduce dementia risk in aging, but varying reports on its effectiveness make it challenging to ascribe what level of exercise will have significant longer-term effects on important functions such as hippocampal-based learning and memory. This study compared the effect of three different 6-month exercise regimens on hippocampal-dependent cognition in healthy, elderly individuals. Participants, aged 65-85 with no cognitive deficits, were randomly assigned to one of three exercise interventions (low (LIT), medium (MIT), and High intensity interval training (HIIT), respectively). Each participant attended 72 supervised exercise sessions over a 6-month period. A total of 151 participants completed all sessions. Cognitive testing for hippocampal performance occurred monthly, as did blood collection, and continued for up to 5 years following initiation of the study. Multimodal 7 Tesla MRI scans were taken at commencement, 6 and 12 months. After 6 months, only the HIIT group displayed significant improvement in hippocampal function, as measured by paired associative learning (PAL). MRI from the HIIT group showed abrogation of the age-dependent volumetric decrease within several cortical regions including the hippocampus and improved functional connectivity between multiple neural networks not seen in the other groups. HIIT-mediated changes in the circulating levels of brain-derived neurotrophic factor (BDNF) and cortisol correlated to improved hippocampal-dependent cognitive ability. These findings demonstrate that HIIT significantly improves and prolongs the hippocampal-dependent cognitive health of aged individuals. Importantly, improvement was retained for at least 5 years following initiation of HIIT, suggesting that the changes seen in hippocampal volume and connectivity underpin this long-term maintenance. Sustained improvement in hippocampal function to this extent confirms that such exercise-based interventions can provide significant protection against hippocampal cognitive decline in the aged population. The changes in specific blood factor levels also may provide useful biomarkers for choosing the optimal exercise regimen to promote cognitive improvement.

4.
Support Care Cancer ; 31(12): 724, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38012463

RESUMEN

PURPOSE: Growing recognition of the gut microbiome as an influential modulator of cancer treatment efficacy and toxicity has led to the emergence of clinical interventions targeting the microbiome to enhance cancer and health outcomes. The highly modifiable nature of microbiota to endogenous, exogenous, and environmental inputs enables interventions to promote resilience of the gut microbiome that have rapid effects on host health, or response to cancer treatment. While diet, probiotics, and faecal microbiota transplant are primary avenues of therapy focused on restoring or protecting gut function in people undergoing cancer treatment, the role of physical activity and exercise has scarcely been examined in this population. METHODS: A narrative review was conducted to explore the nexus between cancer care and the gut microbiome in the context of physical activity and exercise as a widely available and clinically effective supportive care strategy used by cancer survivors. RESULTS: Exercise can facilitate a more diverse gut microbiome and functional metabolome in humans; however, most physical activity and exercise studies have been conducted in healthy or athletic populations, primarily using aerobic exercise modalities. A scarcity of exercise and microbiome studies in cancer exists. CONCLUSIONS: Exercise remains an attractive avenue to promote microbiome health in cancer survivors. Future research should elucidate the various influences of exercise modalities, intensities, frequencies, durations, and volumes to explore dose-response relationships between exercise and the gut microbiome among cancer survivors, as well as multifaceted approaches (such as diet and probiotics), and examine the influences of exercise on the gut microbiome and associated symptom burden prior to, during, and following cancer treatment.


Asunto(s)
Microbioma Gastrointestinal , Neoplasias , Probióticos , Deportes , Humanos , Microbioma Gastrointestinal/fisiología , Ejercicio Físico/fisiología , Neoplasias/terapia , Dieta , Probióticos/uso terapéutico
5.
J Physiol ; 601(21): 4691-4697, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37732418

RESUMEN

High intensity interval training (HIIT) has been shown to consistently elicit rapid and significant adaptations in a number of physiological systems, across many different healthy and clinical populations. In addition, there is increasing interest in how some acute, yet transient responses to high intensity exercise potentially reduce the risks of particular diseases. Recent work has shown that discrete, brief bouts of high intensity exercise (termed 'exercise snacks') can improve glucose control and vascular health and thus counter the negative cardiometabolic consequences of prolonged, uninterrupted periods of inactivity. In this brief review, we advance the case, using evidence available from pre-clinical studies in the exercise oncology literature, that brief, frequently completed bouts of high intensity exercise embedded within an individual's overall daily and weekly physical activity schedule, may transiently impact the tumour microenvironment and improve the health outcomes for those who have been diagnosed and treated for cancer.


Asunto(s)
Enfermedades Cardiovasculares , Neoplasias , Humanos , Bocadillos , Ejercicio Físico/fisiología , Enfermedades Cardiovasculares/prevención & control , Neoplasias/terapia , Microambiente Tumoral
6.
Med Sci Sports Exerc ; 55(12): 2214-2227, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37535331

RESUMEN

INTRODUCTION: High rates of disease- and treatment-related symptoms, such as bone lesions, in people with multiple myeloma (MM) create uncertainty on the safety and feasibility of exercise. This study determined the safety, feasibility, and acceptability of an individualized exercise medicine program for people with MM at any disease stage. METHODS: A multisite, randomized waitlist-controlled trial was conducted of an individualized, high-intensity aerobic, resistance, and impact-loading exercise program. The exercise sessions were supervised twice weekly by accredited exercise physiologists, with one additional unsupervised session per week, for 12 wk. Safety was determined by number of adverse and serious adverse events. Feasibility outcome measures were study eligibility, recruitment, adherence, and attrition. Acceptability was determined by qualitative interviews and subjective levels of enjoyment. RESULTS: Of 203 people with MM screened, 88% were eligible, with 34% accepting participation (60 people) and 20% attrition for the between-group analysis, meeting a priori criteria (≥25% and <25%, respectively). No adverse or serious adverse events attributed to testing and/or exercise training were reported. Attendance at supervised exercise sessions was 98%, with 45% completion of the home-based exercise sessions. Adherence rates were 35%, 63%, and 34% for the aerobic, resistance, and impact-loading protocols, with 55%, 80%, and 37% of participants meeting a priori criteria (75% of protocol). Acceptability of the exercise program was high (mean, 82%; 95% confidence interval, 78%-87%) and highly supported by qualitative responses. CONCLUSIONS: An individualized, high-intensity aerobic, resistance, and impact-loading exercise medicine program is safe and acceptable, and feasible by some measures for people with MM. Adherence to the prescribed exercise protocols was limited by comorbidities and disease symptoms. Strategies to improve unsupervised exercise completion are warranted in this population.


Asunto(s)
Mieloma Múltiple , Humanos , Mieloma Múltiple/terapia , Estudios de Factibilidad , Ejercicio Físico , Terapia por Ejercicio/métodos , Comorbilidad
7.
J Cancer Surviv ; 17(3): 569-594, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37074621

RESUMEN

PURPOSE: Exercise interventions can increase physical activity and wellbeing of people living with/beyond cancer. However, little is known about maintenance of physical activity in this population ≥ 6 months post-exercise intervention, when theoretical evidence suggests behaviour maintenance occurs. Study aims are to (i) systematically review maintenance of physical activity ≥ 6-month post-exercise intervention, and (ii) investigate the influence of behaviour change techniques (BCTs) on physical activity maintenance in people living with/beyond cancer. METHODS: CINAHL, CENTRAL, EMBASE and PubMed databases were searched for randomised controlled trials up to August 2021. Trials including adults diagnosed with cancer that assessed physical activity ≥ 6 months post-exercise intervention were included. RESULTS: Of 142 articles assessed, 21 reporting on 18 trials involving 3538 participants were eligible. Five (21%) reported significantly higher physical activity ≥ 6 months post-exercise intervention versus a control/comparison group. Total number of BCTs (M = 8, range 2-13) did not influence intervention effectiveness. The BCTs Social support, Goal setting (behaviour), and Action planning, alongside supervised exercise, were important, but not sufficient, components for long-term physical activity maintenance. CONCLUSIONS: Evidence for long-term physical activity maintenance post-exercise intervention for people living with/beyond cancer is limited and inconclusive. Further research is required to ensure the physical activity and health benefits of exercise interventions do not quickly become obsolete. IMPLICATIONS FOR CANCER SURVIVORS: Implementation of the BCTs Social support, Goal setting (behaviour), and Action planning, alongside supervised exercise, may enhance physical activity maintenance and subsequent health outcomes in people living with/beyond cancer.


Asunto(s)
Terapia Conductista , Ejercicio Físico , Neoplasias , Humanos , Terapia por Ejercicio , Neoplasias/terapia , Supervivientes de Cáncer
8.
J Cancer Surviv ; 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37079184

RESUMEN

PURPOSE: Cancer treatments exert vascular toxic effects that can lead to the development of cardiovascular disease. Exercise training has the potential to prevent or reduce cancer treatment-induced damage to vascular structure and function. This systematic review with meta-analyses aimed to determine the isolated effects of exercise training on vascular outcomes in people with cancer. METHODS: Seven electronic databases were searched on 20 September 2021 to identify randomised controlled trials, quasi-randomised trials, pilot and cohort studies. Included studies implemented a structured exercise intervention and assessed vascular structure and/or function in people during or following cancer treatment. Meta-analyses examined the effects of exercise training on endothelial function (via brachial artery flow-mediated dilation) and arterial stiffness (via pulse wave velocity). Methodological quality was assessed using the Cochrane Quality Assessment tool and modified Newcastle-Ottawa Quality Appraisal tool. Grading of Recommendations, Assessment, Development and Evaluations framework was used to assess the certainty of evidence. RESULTS: Ten studies (discussed across 11 articles) met the inclusion criteria. Methodological quality of the included studies was moderate (71% average). Exercise improved vascular function when compared to control (standardised mean difference = 0.34, 95% CI (0.01, 0.67); p = 0.044: studies = 5, participants = 171), but not pulse wave velocity (standardised mean difference = - 0.64, 95% CI (- 1.29, 0.02); p = 0.056: studies = 4, participants = 333). The certainty of evidence was moderate for flow-mediated dilation and low for pulse wave velocity. CONCLUSIONS: Compared to usual care, exercise training significantly improves flow-mediated dilation (endothelial function) but not pulse wave analysis, in people treated for cancer. IMPLICATIONS FOR CANCER SURVIVORS: Exercise may improve vascular health in individuals during and following cancer treatment.

9.
Nutrients ; 15(6)2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36986264

RESUMEN

This study systematically reviewed all human longitudinal exercise interventions that reported changes in the gut microbiota; frequency, intensity, duration and type of exercise were assessed to determine the influence of these variables on changes to the gut microbiota in both healthy individuals and clinical populations (PROPERO registration: CRD42022309854). Using PRISMA guidelines, trials analysing gut microbiota change with exercise interventions were included independent of trial randomisation, population, trial duration or analysis technique. Studies were excluded when microbiota abundance was not reported or when exercise was combined with other interventions. Twenty-eight trials were included, of which twelve involved healthy populations only and sixteen involved mixed or clinical-only populations. The findings show that participation in exercise of moderate to high-intensity for 30-90 min ≥3 times per week (or between 150-270 min per week) for ≥8 weeks is likely to produce changes in the gut microbiota. Exercise appears to be effective in modifying the gut microbiota in both clinical and healthy populations. A more robust methodology is needed in future studies to improve the certainty of the evidence.


Asunto(s)
Microbioma Gastrointestinal , Humanos , Ejercicio Físico , Estado de Salud , Prescripciones
10.
Cancer Epidemiol Biomarkers Prev ; 32(5): 588-596, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36867865

RESUMEN

The protective effect of physical activity on breast cancer incidence may partially be mediated by inflammation. Systematic searches of Medline, EMBASE, and SPORTDiscus were performed to identify intervention studies, Mendelian randomization studies, and prospective cohort studies that examined the effects of physical activity on circulating inflammatory biomarkers in adult women. Meta-analyses were performed to generate effect estimates. Risk of bias was assessed, and the Grading of Recommendations Assessment, Development, and Evaluation system was used to determine the overall quality of the evidence. Thirty-five intervention studies and one observational study met the criteria for inclusion. Meta-analyses of randomized controlled trials (RCT) indicated that, compared with control groups, exercise interventions reduced levels of C-reactive protein (CRP) [standardized mean difference (SMD) = -0.27, 95% confidence interval (CI) = -0.62 to 0.08), tumor necrosis factor alpha (TNFα, SMD = -0.63, 95% CI = -1.04 to -0.22), interleukin-6 (IL6, SMD = -0.55, 95% CI = -0.97 to -0.13) and leptin (SMD = -0.50, 95% CI = -1.10 to 0.09). Owing to heterogeneity in effect estimates and imprecision, evidence strength was graded as low (CRP, leptin) or moderate (TNFα and IL6). High-quality evidence indicated that exercise did not change adiponectin levels (SMD = 0.01, 95% CI = -0.14 to 0.17). These findings provide support for the biological plausibility of the first part of the physical activity-inflammation-breast cancer pathway.


Asunto(s)
Neoplasias de la Mama , Leptina , Femenino , Adulto , Humanos , Factor de Necrosis Tumoral alfa , Interleucina-6 , Calidad de Vida , Ejercicio Físico , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/prevención & control , Proteína C-Reactiva , Inflamación
11.
Cancer Epidemiol Biomarkers Prev ; 32(5): 597-605, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36867866

RESUMEN

This review synthesized and appraised the evidence for an effect of inflammation on breast cancer risk. Systematic searches identified prospective cohort and Mendelian randomization studies relevant to this review. Meta-analysis of 13 biomarkers of inflammation were conducted to appraise the evidence for an effect breast cancer risk; we examined the dose-response of these associations. Risk of bias was evaluated using the ROBINS-E tool and the quality of evidence was appraised with Grading of Recommendations Assessment, Development, and Evaluation. Thirty-four observational studies and three Mendelian randomization studies were included. Meta-analysis suggested that women with the highest levels of C-reactive protein (CRP) had a higher risk of developing breast cancer [risk ratio (RR) = 1.13; 95% confidence interval (CI), 1.01-1.26] compared with women with the lowest levels. Women with highest levels of adipokines, particularly adiponectin (RR = 0.76; 95% CI, 0.61-0.91) had a reduced breast cancer risk, although this finding was not supported by Mendelian randomization analysis. There was little evidence of an effect of cytokines, including TNFα and IL6, on breast cancer risk. The quality of evidence for each biomarker ranged from very low to moderate. Beyond CRP, the published data do not clearly support the role of inflammation in the development of breast cancer.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/etiología , Estudios Prospectivos , Inflamación/complicaciones , Riesgo , Proteína C-Reactiva , Ejercicio Físico
12.
Med Sci Sports Exerc ; 55(3): 558-568, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36730979

RESUMEN

Exercise has been shown to improve physical and psychosocial outcomes for people across the cancer care continuum. A proposed mechanism underpinning the relationship between exercise and cancer outcomes is exercise-induced immunomodulation via secretion of anti-inflammatory myokines from skeletal muscle tissue. Myokines have the potential to impair cancer growth through modulation of natural killer (NK) cells and CD8+ T cells while improving the effectiveness of cancer therapies. Interleukin-15 (IL-15), one of the most abundant myokines found in skeletal muscle, has a key immunoregulatory role in supporting the proliferation and maturation of T cells and NK cells, which have a key role in the host's immune response to cancer. Furthermore, IL-15 is being explored clinically as an immunotherapy agent with doses similar to the IL-15 concentrations released by skeletal muscle during exercise. Here we review the role of IL-15 within the immune system, examine how IL-15 is produced as a myokine during exercise, and how it may improve outcomes for people with cancer, specifically as an adjuvant or neoadjuvant to immunotherapy. We summarize the available evidence showing changes in IL-15 in response to both acute exercise and training, and the results are inconsistent; higher quality research is needed to advance the understanding of how exercise-mediated increases in IL-15 potentially benefit those who are being treated for, or who have had, cancer.


Asunto(s)
Interleucina-15 , Neoplasias , Humanos , Interleucina-15/fisiología , Ejercicio Físico/fisiología , Músculo Esquelético/fisiología , Inmunoterapia , Inmunomodulación , Neoplasias/terapia
13.
Clin Lymphoma Myeloma Leuk ; 23(2): 86-96, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36450625

RESUMEN

Bone lesions and other disease- and treatment-related side effects commonly experienced by people with multiple myeloma (MM) may impede their ability to exercise. This systematic review evaluated the safety, feasibility, and efficacy of exercise program participation on the physiological and/or psychological health of people with MM. Literature searches were conducted through five electronic databases and appraised using the Delphi list of criteria. Controlled trials that assessed the safety and feasibility of an exercise intervention and its effects on disease- or treatment-related symptoms in people with MM were included. Seven studies of varying quality involving 563 participants were included. All studies concluded that exercise was safe, reporting zero serious and 4 adverse events attributable to exercise testing or training. Attendance ranged from 58% to 96%, however no study reported adherence to the exercise prescription. Compared to a control group, exercise did not appear to affect fatigue, depression, anxiety, body composition, quality of life, or sleep. Isolated studies identified between-group differences favoring exercise in lower limb strength (+8.4 kg, 95% CI 0.5, 16.3, P= .04), peak oxygen uptake (+1.2 mL/kg/min, 95% CI 0.3, 3.7, P= .02), physical activity (+6.5MET-hs/wk, P< .001), stem cell collection attempts (1.1 ± 0.2 vs. 1.5 ± 0.9, P< .01), and red blood cell (1.8 ± 2.2 vs. 2.4 ± 2.6, P< .05) and platelet transfusions (2.3 ± 1.6 vs. 3.5 ± 3.4, P < .05) during transplantation. Exercise interventions appear safe and well attended by people with MM. The lack of improvements in disease- and treatment-related symptoms requires further exploration to determine whether exercise is a sufficient stimulus to elicit benefits in this unique population.


Asunto(s)
Mieloma Múltiple , Humanos , Mieloma Múltiple/terapia , Calidad de Vida , Estudios de Factibilidad , Ejercicio Físico , Terapia por Ejercicio/psicología
14.
Cancer Epidemiol Biomarkers Prev ; 31(12): 2116-2125, 2022 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-36464995

RESUMEN

Perturbation of the insulin/insulin-like growth factor (IGF) signaling system is often cited as a mechanism driving breast cancer risk. A systematic review identified prospective cohort studies and Mendelian randomization studies that examined the effects of insulin/IGF signaling (IGF, their binding proteins (IGFBP), and markers of insulin resistance] on breast cancer risk. Meta-analyses generated effect estimates; risk of bias was assessed and the Grading of Recommendations Assessment, Development and Evaluation system applied to evaluate the overall quality of the evidence. Four Mendelian randomization and 19 prospective cohort studies met our inclusion criteria. Meta-analysis of cohort studies confirmed that higher IGF-1 increased risk of breast cancer; this finding was supported by the Mendelian randomization studies. IGFBP-3 did not affect breast cancer. Meta analyses for connecting-peptide and fasting insulin showed small risk increases, but confidence intervals were wide and crossed the null. The quality of evidence obtained ranged from 'very low' to 'moderate'. There were insufficient studies to examine other markers of insulin/IGF signaling. These findings do not strongly support the biological plausibility of the second part of the physical activity-insulin/IGF signaling system-breast cancer pathway. Robust conclusions cannot be drawn due to the dearth of high quality studies. See related article by Swain et al., p. 2106.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Insulina , Estudios Prospectivos , Mama , Ejercicio Físico
15.
Cancer Epidemiol Biomarkers Prev ; 31(12): 2106-2115, 2022 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-36464996

RESUMEN

Physical activity may reduce the risk of developing breast cancer via its effect on the insulin/insulin-like growth factor (IGF) signaling system. A systematic review searched for randomized controlled trials (RCT), Mendelian randomization and prospective cohort studies that examined the effects of physical activity on insulin/IGF signaling [IGFs, their binding proteins (IGFBP), and markers of insulin resistance] in adult women. Meta-analyses were performed to generate effect estimates. Risk of bias was assessed, and the Grading of Recommendations Assessment, Development, and Evaluation system used to determine the overall quality of the evidence. Fifty-eight RCTs met our inclusion criteria, no observational or Mendelian randomization studies met the criteria for inclusion. Meta-analyses indicated that physical activity interventions (vs. control) reduced fasting insulin, the Homeostatic Model Assessment for Insulin Resistance and fasting glucose. Physical activity increased IGF-1, but there was no clear effect on IGFBP-3 or the ratio of IGF-1:IGFBP-3. Strong evidence was only established for fasting insulin and insulin resistance. Further research is needed to examine the effect of physical activity on C-peptide and HBA1c in women. Reductions in fasting insulin and insulin resistance following exercise suggest some biological plausibility of the first part of the physical activity-insulin/IGF signaling-breast cancer pathway. See related article by Drummond et al., p. 2116.


Asunto(s)
Neoplasias de la Mama , Ejercicio Físico , Resistencia a la Insulina , Adulto , Femenino , Humanos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/prevención & control , Ejercicio Físico/fisiología , Insulina/sangre , Insulina/metabolismo , Resistencia a la Insulina/fisiología , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Transducción de Señal
16.
J Physiol ; 600(24): 5189-5201, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36369926

RESUMEN

Physical activity is associated with reduced risks of colorectal cancer (CRC) incidence, recurrence and mortality. While these findings are consistent, the mechanism/s underlying this association remain unclear. Growing evidence supports the many ways in which differing characteristics of the gut microbiota can be tumourigenic or protective against CRC. CRC is characterised by significant dysbiosis including reduced short chain fatty acid-producing bacteria. Recent findings suggest that exercise can modify the gut microbiota, and these changes are inverse to the changes seen with CRC; however, this exercise-microbiota interaction is currently understudied in CRC. This review summarises parallel areas of research that are rapidly developing: The exercise-gut microbiota research and cancer-gut microbiota research and highlights the salient similarities. Preliminary evidence suggests that these areas are linked, with exercise mediating changes that promote the antitumorigenic characteristics of the gut microbiota. Future mechanistic and population-specific studies are warranted to confirm the physiological mechanism/s by which exercise changes the gut microbiota, and the influence of the exercise-gut interaction on cancer specific outcomes in CRC.


Asunto(s)
Neoplasias Colorrectales , Microbioma Gastrointestinal , Microbiota , Humanos , Microbioma Gastrointestinal/fisiología , Neoplasias Colorrectales/microbiología , Disbiosis/complicaciones , Disbiosis/microbiología , Bacterias
17.
Front Physiol ; 13: 967169, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36072844

RESUMEN

Purpose: This study assessed the biological reliability of peripheral human cytokines and adipokines, and the influence of participant characteristics on total error. This has essential application to interventional cytokine measurement to ensure that reported results are interpreted with confidence. Methods: Participants (49% female, 18-85 years, n = 84) completed two consecutive-day testing sessions. Participants provided a venous blood sample at the same time of day across two consecutive days, under standardized participant presentation, including 24-h rested and 12-h fasted conditions. Multiplex immunoassay was used to assess inflammatory analytes from samples (predominantly plasma). Repeat measurements were conducted between-day for total precision quantification, and technical (technique) error was negated from the total to provide an estimate of biological (attributed to participant presentation) error. Results: Whilst there was no evidence of statistically significant biological error, a small amount of biological error was consistently present across most analytes (∼3.3%/0.07 pg/ml), which was largest for measurement of leptin (7.3%/210 pg/ml). There was also an influence of sex on reliability of leptin and adiponectin (total model explained 6-7% of error variation), where females demonstrated the greatest error. Conclusion: Biological error reported in this study should be applied to any future study or individual with a repeated measurement of cytokine concentrations over time that maintain best practice procedures (12-h fasted, 24-h rested). In most cases, raw error should be used, with exceptions for women for measurement of leptin and adiponectin. This approach will ensure that results are reported with certainty for improved reporting of intervention efficacy.

18.
Artículo en Inglés | MEDLINE | ID: mdl-35565100

RESUMEN

Background: Androgen deprivation therapy (ADT) in prostate cancer has been shown to deteriorate body composition (reduced lean mass and increased body and fat mass) and increase the risk of cardiovascular morbidity. The Mediterranean style dietary pattern (MED-diet) and high intensity interval training (HIIT) may synergistically alleviate these side effects and improve quality of life in men treated with ADT. Methods: Twenty-three men (65.9 ± 7.8 years; body mass index: 29.6 ± 2.7 kg/m2; ADT duration: 33.8 ± 35.6 months) receiving ADT for ≥3 months were randomly assigned (1:1) to 20 weeks of usual care or the MED-diet (10 nutrition consults) with HIIT (4 × 4 min 85−95% heart rate peak, 3× week, starting at 12 weeks). Results: The MED-diet with HIIT significantly improved cardiorespiratory fitness (+4.9 mL·kg−1·min, p < 0.001), and body mass (−3.3 kg, p < 0.001) compared to the usual care group at 20 weeks. Clinically meaningful (≥3 points) improvements were seen in quality of life and cancer-related fatigue after 20 weeks. Conclusions: The MED-diet with HIIT increased cardiorespiratory fitness and reduced body weight in men with prostate cancer treated with ADT. Larger trials determining whether the MED-diet with HIIT translates to cardiovascular benefits are warranted.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad , Neoplasias de la Próstata , Antagonistas de Andrógenos/uso terapéutico , Andrógenos/uso terapéutico , Composición Corporal , Dieta , Humanos , Masculino , Proyectos Piloto , Neoplasias de la Próstata/tratamiento farmacológico , Calidad de Vida
19.
Curr Oncol ; 29(2): 901-923, 2022 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-35200576

RESUMEN

People with multiple myeloma (MM) are second only to people with lung cancer for the poorest reported health-related quality of life (HRQoL) of all cancer types. Whether exercise can improve HRQoL in MM, where bone pain and lesions are common, requires investigation. This trial aims to evaluate the efficacy of an exercise intervention compared with control on HRQoL in people with MM. Following baseline testing, people with MM (n = 60) will be randomized to an exercise (EX) or waitlist control (WT) group. EX will complete 12-weeks of supervised (24 sessions) and unsupervised (12 sessions) individualized, modular multimodal exercise training. From weeks 12-52, EX continue unsupervised training thrice weekly, with one optional supervised group-based session weekly from weeks 12-24. The WT will be asked to maintain their current activity levels for the first 12-weeks, before completing the same protocol as EX for the following 52 weeks. Primary (patient-reported HRQoL) and secondary (bone health and pain, fatigue, cardiorespiratory fitness, muscle strength, body composition, disease response, and blood biomarkers) outcomes will be assessed at baseline, 12-, 24- and 52-weeks. Adverse events, attendance, and adherence will be recorded and cost-effectiveness analysis performed. The findings will inform whether exercise should be included as part of standard myeloma care to improve the health of this unique population.


Asunto(s)
Mieloma Múltiple , Ejercicio Físico , Terapia por Ejercicio , Humanos , Mieloma Múltiple/terapia , Fuerza Muscular/fisiología , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto
20.
Appl Physiol Nutr Metab ; 47(5): 482-494, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35041556

RESUMEN

This study investigated the acceptable accuracy of common body composition techniques compared with the reference 4-compartment (4C-R) model, which has not been investigated in a sample with diverse characteristics, including age and sex. Techniques included components of the 4C-R model [dual-energy X-ray absorptiometry, air displacement plethysmography, deuterium dilution (DD)] and surrogate compartment models, which utilised bioelectrical impedance spectroscopy (BIS) rather than DD. Men and women (sex = 1:1, 18-85 years, n = 90) completed body composition testing under best-practice guidance. For measurement of individuals, only the reference 3-compartment (3C-R) equation met acceptable error limits (<5% error among individuals) within the a priori cut-point (80%) for fat-free mass (FFM; CV = 0.52%) and fat mass (FM; CV = 1.61%). However, all investigated techniques reached equivalency to the 4C-R model for FFM on average (CV = 0.52-4.31%), but for FM only the 3C and 4C equations that included quantification of total body water (TBW) by DD or BIS reached equivalency overall (CV = 1.61-6.68%). Sex and age minimally influenced accuracy. Only the 3C-R or 4C-R equations are supported for acceptable individual accuracy for both FFM and FM. For group estimates any investigated technique could be used with acceptable accuracy for FFM; however, for FM, inclusion of TBW measurement within a compartment model is necessary. Novelty: Only the referent 3C and 4C models (including deuterium dilution) provide accurate body composition results that are acceptable for measurement of individuals in the general population. For group estimates of lean mass in the general population, compartments models that include TBW must be used for accurate measurement.


Asunto(s)
Composición Corporal , Pletismografía , Absorciometría de Fotón/métodos , Agua Corporal , Deuterio , Impedancia Eléctrica , Femenino , Humanos , Masculino , Pletismografía/métodos , Reproducibilidad de los Resultados
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