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1.
BMC Med ; 21(1): 488, 2023 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-38066548

RESUMEN

BACKGROUND: Preliminary evidence demonstrates some parameters of metabolic control, including glycaemic control, lipid control and insulin resistance, vary across the menstrual cycle. However, the literature is inconsistent, and the underlying mechanisms remain uncertain. This study aimed to investigate the association between the menstrual cycle phase and metabolites and to explore potential mediators and moderators of these associations. METHODS: We undertook a cross-sectional cohort study using UK Biobank. The outcome variables were glucose; triglyceride; triglyceride to glucose index (TyG index); total, HDL and LDL cholesterol; and total to HDL cholesterol ratio. Generalised additive models (GAM) were used to investigate non-linear associations between the menstrual cycle phase and outcome variables. Anthropometric, lifestyle, fitness and inflammatory markers were explored as potential mediators and moderators of the associations between the menstrual cycle phase and outcome variables. RESULTS: Data from 8694 regularly menstruating women in UK Biobank were analysed. Non-linear associations were observed between the menstrual cycle phase and total (p < 0.001), HDL (p < 0.001), LDL (p = 0.012) and total to HDL cholesterol (p < 0.001), but not glucose (p = 0.072), triglyceride (p = 0.066) or TyG index (p = 0.100). Neither anthropometric, physical fitness, physical activity, nor inflammatory markers mediated the associations between the menstrual cycle phase and metabolites. Moderator analysis demonstrated a greater magnitude of variation for all metabolites across the menstrual cycle in the highest and lowest two quartiles of fat mass and physical activity, respectively. CONCLUSIONS: Cholesterol profiles exhibit a non-linear relationship with the menstrual cycle phase. Physical activity, anthropometric and fitness variables moderate the associations between the menstrual cycle phase and metabolite concentration. These findings indicate the potential importance of physical activity and fat mass as modifiable risk factors of the intra-individual variation in metabolic control across the menstrual cycle in pre-menopausal women.


Asunto(s)
Resistencia a la Insulina , Femenino , Humanos , HDL-Colesterol , Estudios Transversales , Bancos de Muestras Biológicas , Menstruación , Ciclo Menstrual , Factores de Riesgo , Triglicéridos , Glucosa
2.
Physiol Genomics ; 54(1): 1-10, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34796732

RESUMEN

Cyclical changes in hormone profiles across the menstrual cycle are associated with alterations in metabolic control. MicroRNAs (miRNAs) contribute to regulating metabolic control, including adipose tissue metabolism. How fluctuations in hormonal profiles across the menstrual cycle affect adipose tissue miRNA expression remains unknown. Eleven healthy, regularly menstruating females underwent four sampling visits across their menstrual cycle. Subcutaneous abdominal adipose tissue and venous blood samples were collected at each sampling visit. Luteinizing hormone (LH) tests, calendar counting, and serum hormone concentrations were used to determine menstrual cycle phases: early-follicular (EF), late-follicular (LF), postovulatory (PO), and midluteal (ML). Serum follicle-stimulating hormone, LH, estrogen, progesterone, and testosterone were determined using multiplex magnetic bead panels and enzyme-linked immunosorbent assays. Global adipose tissue miRNA expression levels were determined via microarray in a subset of participants (n = 8) and 17 candidate miRNAs were validated by RT-qPCR in the whole cohort (n = 11). Global analysis of adipose tissue miRNA expression identified 33 miRNAs significantly altered across the menstrual cycle; however, no significant differences remained after correcting for multiple testing (P > 0.05). RT-qPCR analysis of candidate miRNAs revealed miR-497-5p expression was significantly altered across the menstrual cycle ([Formula: see text] = 0.18, P = 0.03); however, post hoc tests did not reveal any significant differences between menstrual cycle phases (P > 0.05). miR-30c-5p was associated with testosterone concentration (R2 = 0.13, P = 0.033). These pilot data indicate differences in adipose tissue miRNAs in healthy women across the menstrual cycle and a weak association with ovarian hormones. Further research in larger sample sizes is required to confirm regulation of miRNA expression across the menstrual cycle.


Asunto(s)
Tejido Adiposo , Ciclo Menstrual , Menstruación , MicroARNs , Estradiol , Femenino , Humanos , MicroARNs/genética , Proyectos Piloto , Progesterona
3.
Br J Sports Med ; 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33441332

RESUMEN

OBJECTIVES: To determine if subpopulations of students benefit equally from school-based physical activity interventions in terms of cardiorespiratory fitness and physical activity. To examine if physical activity intensity mediates improvements in cardiorespiratory fitness. DESIGN: Pooled analysis of individual participant data from controlled trials that assessed the impact of school-based physical activity interventions on cardiorespiratory fitness and device-measured physical activity. PARTICIPANTS: Data for 6621 children and adolescents aged 4-18 years from 20 trials were included. MAIN OUTCOME MEASURES: Peak oxygen consumption (VO2Peak mL/kg/min) and minutes of moderate and vigorous physical activity. RESULTS: Interventions modestly improved students' cardiorespiratory fitness by 0.47 mL/kg/min (95% CI 0.33 to 0.61), but the effects were not distributed equally across subpopulations. Girls and older students benefited less than boys and younger students, respectively. Students with lower levels of initial fitness, and those with higher levels of baseline physical activity benefitted more than those who were initially fitter and less active, respectively. Interventions had a modest positive effect on physical activity with approximately one additional minute per day of both moderate and vigorous physical activity. Changes in vigorous, but not moderate intensity, physical activity explained a small amount (~5%) of the intervention effect on cardiorespiratory fitness. CONCLUSIONS: Future interventions should include targeted strategies to address the needs of girls and older students. Interventions may also be improved by promoting more vigorous intensity physical activity. Interventions could mitigate declining youth cardiorespiratory fitness, increase physical activity and promote cardiovascular health if they can be delivered equitably and their effects sustained at the population level.

4.
BMC Med ; 18(1): 62, 2020 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-32178667

RESUMEN

BACKGROUND: School-based physical activity and running programmes, such as The Daily Mile™, are increasing in popularity globally. The aim of this research was to examine the acute impact of such classroom physical activity breaks on cognition and affective wellbeing. METHODS: A total of 5463 school pupils from 332 schools took part in a citizen science project with a repeated measures design. They completed tasks of cognition (inhibition, verbal, and visuo-spatial working memory) and the Children's Feeling Scale and Felt Arousal Scale before and after three different outdoor activities: a classroom break of 15 min of self-paced activity, a near maximal exhaustion activity (the bleep test), and a no-exercise control group where pupils sat or stood outside. Wellbeing and fitness were examined as mediators of the relationship between outdoor activity and cognition. RESULTS: Fifteen minutes of self-paced outdoor activity was beneficial for pupils' cognition and wellbeing in comparison to both other activities (Cohen's d effect sizes ranging from 0.04 to 0.22; small). The relationship with cognition was not mediated by participants' fitness level and was only partially mediated by wellbeing. Change scores for alertness were higher after the bleep test compared to the control activity but similar for all other outcomes. CONCLUSIONS: Taking a break from the classroom to complete 15 min of self-paced physical activity should be considered a worthwhile activity by class teachers, school management, and policymakers. Additionally, more intense physical activity should not be considered to be detrimental.


Asunto(s)
Ciencia Ciudadana/normas , Cognición/fisiología , Ejercicio Físico/fisiología , Instituciones Académicas/estadística & datos numéricos , Niño , Femenino , Humanos , Masculino , Autocontrol
5.
BMC Med ; 17(1): 97, 2019 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-31113425

RESUMEN

We thank Daly-Smith et al. for taking the time to read the results of our pilot research study, describing it as an important and welcome contribution. Nonetheless, the authors argue six points against our conclusion. We contend that we addressed three of these points in our original discussion and disagree with their remaining points. Overall, their Commentary adds little to the topic of research into the Daily Mile™ that we had not already raised in our discussion. Additionally, they attribute statements to us that we did not make and ignore the raising of key issues in our original article. Given this, we stand by our original peer-reviewed conclusion that introducing the Daily Mile™ to the primary school day appears to be an effective intervention for increasing levels of moderate to vigorous physical activity, reducing sedentary time, increasing physical fitness and improving body composition, and that these findings have relevance for teachers, policy-makers, public health practitioners and health researchers.


Asunto(s)
Ejercicio Físico , Instituciones Académicas , Composición Corporal , Niño , Humanos , Aptitud Física , Proyectos Piloto
6.
BMC Med ; 16(1): 64, 2018 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-29743076

RESUMEN

BACKGROUND: The Daily Mile is a physical activity programme made popular by a school in Stirling, Scotland. It is promoted by the Scottish Government and is growing in popularity nationally and internationally. The aim is that each day, during class time, pupils run or walk outside for 15 min (~1 mile) at a self-selected pace. It is anecdotally reported to have a number of physiological benefits including increased physical activity, reduced sedentary behaviour, increased fitness and improved body composition. This study aimed to investigate these reports. METHODS: We conducted a quasi-experimental repeated measures pilot study in two primary schools in the Stirling Council area: one school with, and one without, intention to introduce the Daily Mile. Pupils at the control school followed their usual curriculum. Of the 504 children attending the schools, 391 children in primary classes 1-7 (age 4-12 years) at the baseline assessment took part. The follow-up assessment was in the same academic year. Outcomes were accelerometer-assessed average daily moderate to vigorous intensity physical activity (MVPA) and average daily sedentary behaviour, 20-m shuttle run fitness test performance and adiposity assessed by the sum of skinfolds at four sites. Valid data at both time points were collected for 118, 118, 357 and 327 children, respectively, for each outcome. RESULTS: After correction for age and gender, significant improvements were observed in the intervention school relative to the control school for MVPA, sedentary time, fitness and body composition. For MVPA, a relative increase of 9.1 min per day (95% confidence interval or 95%CI 5.1-13.2 min, standardised mean difference SMD = 0.407, p = 0.027) was observed. For sedentary time, there was a relative decrease of 18.2 min per day (10.7-25.7 min, SMD = 0.437, p = 0.017). For the shuttle run, there was a relative increase of 39.1 m (21.9-56.3, SMD = 0.236, p = 0.037). For the skinfolds, there was a relative decrease of 1.4 mm (0.8-2.0 mm, SMD = 0.246, p = 0.036). Similar results were obtained when a correction for socioeconomic groupings was included. CONCLUSIONS: The findings show that in primary school children, the Daily Mile intervention is effective at increasing levels of MVPA, reducing sedentary time, increasing physical fitness and improving body composition. These findings have relevance for teachers, policymakers, public health practitioners, and health researchers.


Asunto(s)
Composición Corporal/fisiología , Ejercicio Físico/fisiología , Aptitud Física/fisiología , Conducta Sedentaria , Niño , Preescolar , Femenino , Humanos , Masculino , Proyectos Piloto , Instituciones Académicas
7.
J Sports Sci ; 35(14): 1411-1419, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27498724

RESUMEN

Cyclists in the Tour de France are endurance specialists. Twin and family studies have shown that approximately 50% of the variance in a number of performance-related phenotypes (whether measured at baseline, i.e., natural talent, or in response to training) including those important to cycling can be explained by genetic variation. Research into the specific genetic variants that are responsible has identified over 200 genes containing common genetic variants involved in the genetic predisposition to physical performance. However, typically these explain only a small portion of the variance, perhaps 1-2% and collectively they rarely explain anything approaching the 50% of the variance identified in the twin and family studies. Thus, there is a gap in our understanding of the relationship between heritability and performance. This gap may be bridged by investigation of rare variants or epigenetic variation or by altering study designs through increased collaborations to pool existing cohorts together. Initial findings from such efforts show promising results. This mini-review will touch on the genetics and epigenetics of sporting performance, how they relate to cyclists in the Tour de France and where best future efforts may be directed as well as discuss some preliminary research findings.


Asunto(s)
Ciclismo/fisiología , Resistencia Física/genética , Resistencia Física/fisiología , Aptitud/fisiología , Conducta Competitiva/fisiología , Epigenómica , Francia , Variación Genética , Humanos , Acondicionamiento Físico Humano
8.
Physiol Genomics ; 48(3): 183-90, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26715623

RESUMEN

Despite numerous attempts to discover genetic variants associated with elite athletic performance, injury predisposition, and elite/world-class athletic status, there has been limited progress to date. Past reliance on candidate gene studies predominantly focusing on genotyping a limited number of single nucleotide polymorphisms or the insertion/deletion variants in small, often heterogeneous cohorts (i.e., made up of athletes of quite different sport specialties) have not generated the kind of results that could offer solid opportunities to bridge the gap between basic research in exercise sciences and deliverables in biomedicine. A retrospective view of genetic association studies with complex disease traits indicates that transition to hypothesis-free genome-wide approaches will be more fruitful. In studies of complex disease, it is well recognized that the magnitude of genetic association is often smaller than initially anticipated, and, as such, large sample sizes are required to identify the gene effects robustly. A symposium was held in Athens and on the Greek island of Santorini from 14-17 May 2015 to review the main findings in exercise genetics and genomics and to explore promising trends and possibilities. The symposium also offered a forum for the development of a position stand (the Santorini Declaration). Among the participants, many were involved in ongoing collaborative studies (e.g., ELITE, GAMES, Gene SMART, GENESIS, and POWERGENE). A consensus emerged among participants that it would be advantageous to bring together all current studies and those recently launched into one new large collaborative initiative, which was subsequently named the Athlome Project Consortium.


Asunto(s)
Rendimiento Atlético , Biomarcadores/metabolismo , Genómica/métodos , Animales , Epigénesis Genética , Europa (Continente) , Humanos , Bancos de Tejidos
9.
Br J Sports Med ; 49(23): 1486-91, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26582191

RESUMEN

The general consensus among sport and exercise genetics researchers is that genetic tests have no role to play in talent identification or the individualised prescription of training to maximise performance. Despite the lack of evidence, recent years have witnessed the rise of an emerging market of direct-to-consumer marketing (DTC) tests that claim to be able to identify children's athletic talents. Targeted consumers include mainly coaches and parents. There is concern among the scientific community that the current level of knowledge is being misrepresented for commercial purposes. There remains a lack of universally accepted guidelines and legislation for DTC testing in relation to all forms of genetic testing and not just for talent identification. There is concern over the lack of clarity of information over which specific genes or variants are being tested and the almost universal lack of appropriate genetic counselling for the interpretation of the genetic data to consumers. Furthermore independent studies have identified issues relating to quality control by DTC laboratories with different results being reported from samples from the same individual. Consequently, in the current state of knowledge, no child or young athlete should be exposed to DTC genetic testing to define or alter training or for talent identification aimed at selecting gifted children or adolescents. Large scale collaborative projects, may help to develop a stronger scientific foundation on these issues in the future.


Asunto(s)
Aptitud/fisiología , Rendimiento Atlético/fisiología , Pruebas Dirigidas al Consumidor/normas , Pruebas Genéticas/normas , Aptitud/ética , Consenso , Decepción , Pruebas Dirigidas al Consumidor/ética , Pruebas Dirigidas al Consumidor/legislación & jurisprudencia , Medicina Basada en la Evidencia , Pruebas Genéticas/ética , Pruebas Genéticas/legislación & jurisprudencia , Genómica , Humanos , Medicina Deportiva/ética , Medicina Deportiva/legislación & jurisprudencia , Medicina Deportiva/normas
10.
Diabetes Metab Syndr Obes ; 16: 2875-2883, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37753482

RESUMEN

Purpose: Type 2 Diabetes mellitus (T2DM) has become a life-threatening health problem around the world. Studies have confirmed that aerobic exercise can prevent the risk of T2DM. Furthermore, recent research showed that salivary amylase gene (AMY1) copy number variation (CNV) could be one of the genetic factors that increased the risk of T2DM. To provide more evidence on how AMY1 CNV and exercise is correlated with the risk of T2DM, we designed this study to show the differences in postprandial carbohydrate metabolism between people with different AMY1 copy numbers, and how aerobic exercise can influence this process. Participants and Methods: Sixteen participants without cardiovascular disease were chosen, 8 with AMY1 CNV≥6 (High CNV group, HCNV), and 8 with AMY1 CNV ≤ 2 (Low CNV group, LCNV). All participants were Chinese, Han nationality, 18 to 40 years old, with fasting blood glucose lower than 6.1 mmol/L and normal blood pressure levels. They were asked to visit the laboratory in fasting state and drink a cup of solution with 75 grams of edible carbohydrate (glucose or starch). After carbohydrate intake, blood samples were taken at certain times at rest or after aerobic exercise. Blood glucose levels were tested with a portable blood glucose monitor, and insulin levels were tested with the enzyme-linked immunosorbent assay (ELISA). Results: The LCNV group had significantly higher resting insulin levels and homeostatic model assessment of insulin resistance (HOMA-IR) than the HCNV group. Compared to the HCNV group, postprandial blood glucose levels and insulin levels were insensitive to starch intake in the LCNV group. However, this difference disappeared after aerobic exercise was added as an intervention. Conclusion: Lower AMY1 CNV could be associated with higher risk of T2DM and complex carbohydrate metabolism disorder, while aerobic exercise can reduce the risk by increasing the carbohydrate utilization rate.

11.
Genes Genomics ; 45(7): 935-943, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37043131

RESUMEN

BACKGROUND: According to the WHO, about 39% of the global adult population were overweight or obese in 2016. Obesity has high heritability, with more than 1000 variants so far identified. There have been reports indicating that salivary amylase gene (AMY1) copy number was one of these variants, yet its association with obesity remains controversial. OBJECTIVE: Our research aimed to provide more evidence on the relationship of AMY1 copy number variation (CNV) with body mass index (BMI) and body composition. METHODS: We recruited 133 Chinese adults (65 males, 68 females, 18-25 years old) with normal fasting blood glucose and blood pressure levels. 19 males were selected for a 10-week intervention to change body composition. After anthropometric measurements, BMI was calculated, and body composition was measured using dual energy X-ray absorptiometry (DEXA). For the 19 selected participants, we collected their height, weight, and body composition data one more time after intervention. All participants were required to leave their saliva samples and their AMY1 copy number was determined by real-time fluorescence quantitative PCR. RESULTS: We failed to find any significant difference in BMI and body composition between different copy number groups. Only a weak correlation was found between body muscle mass and body fat mass. After adjusted for height and weight, AMY1 CNV explained 4.83% of the variance and one single increase in AMY1 CNV can increase 0.214 kg of the body muscle mass, while one single increase in AMY1 CNV can decrease 0.217 kg of the body fat mass and explained 4.69% of the variance. CONCLUSIONS: As a genetic factor, the AMY1 gene copy number variation has only a minor correlation with BMI and body composition, and its effect can easily be hidden by other factors such as individual diet and exercise habit.


Asunto(s)
Composición Corporal , Variaciones en el Número de Copia de ADN , alfa-Amilasas Salivales , Adolescente , Adulto , Femenino , Humanos , Masculino , Adulto Joven , Composición Corporal/genética , Pueblos del Este de Asia , Obesidad/genética , alfa-Amilasas Salivales/genética
12.
Birth Defects Res A Clin Mol Teratol ; 94(8): 626-50, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22851372

RESUMEN

BACKGROUND: Cancer is the second leading cause of death among women of reproductive age. Although the coincidence of pregnancy and cancer is rare and treatment may sometimes be safely delayed, the use of chemotherapeutic agents in pregnancy is sometimes unavoidable or inadvertent. METHODS: We review the literature for the use of antineoplastic agents in single-agent and combination therapy from 1951 through June 2012. We also summarize the evidence relating to teratogenicity of disorder-specific combination chemotherapy treatments for those malignancies frequently encountered in women of childbearing age. Major endpoints were called "adverse pregnancy outcomes" (APOs), to include structural anomalies (congenital malformations), functional defects, blood or electrolyte abnormalities, stillbirths, spontaneous abortions (miscarriages), and fetal, neonatal, or maternal deaths. RESULTS: The registry totals 863 cases. Rates of APOs (and congenital malformations) after any exposure were 33% (16%), 27% (8%), and 25% (6%), for first, second, and third trimesters. Among the groups of cancer drugs, antimetabolites and alkylating agents have the highest rates of APOs. Mitotic inhibitors and antibiotics seem more benign. Mixed results were observed from single-agent exposure, often because of small numbers of exposures. As a whole, the alkylating agents and antimetabolites are more harmful when given as a single agent rather than as part of a regimen. First-trimester exposure poses a more permanent risk to the fetus. CONCLUSIONS: Systematic ascertainment of women early in pregnancy, preferably in a population base, is needed for assessment of true risks. Long-term follow-up is needed to rule out neurobehavioral effects.


Asunto(s)
Antineoplásicos/efectos adversos , Neoplasias/tratamiento farmacológico , Sistema de Registros , Teratógenos/toxicidad , Anomalías Inducidas por Medicamentos/sangre , Anomalías Inducidas por Medicamentos/patología , Aborto Espontáneo/inducido químicamente , Antineoplásicos/administración & dosificación , Antineoplásicos/clasificación , Femenino , Muerte Fetal/inducido químicamente , Feto , Humanos , Muerte Materna , Neoplasias/mortalidad , Embarazo , Trimestres del Embarazo/efectos de los fármacos , Mortinato , Análisis de Supervivencia , Teratógenos/clasificación
13.
Front Psychol ; 13: 812616, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35572274

RESUMEN

Background: School based running programmes, such as The Daily Mile™, positively impact pupils' physical health, however, there is limited evidence on psychological health. Additionally, current evidence is mostly limited to examining the acute impact. The present study examined the longer term impact of running programmes on pupil cognition, wellbeing, and fitness. Method: Data from 6,908 school pupils (mean age 10.2 ± 0.7 years), who were participating in a citizen science project, was examined. Class teachers provided information about participation in school based running programmes. Participants completed computer-based tasks of inhibition, verbal and visual-spatial working memory, as well as the Children's Feeling scale and Felt arousal scale to determine subjective wellbeing. A multistage 20-m shuttle run test was used to estimate fitness. Results: From our total sample of 6,908 school pupils, 474 participants had been taking part in a running programme for <2 months (Shorter term participation); 1,004 participants had Longer Term participation (>3 months); and 5,430 did not take part in a running programme. The Longer Term participation group had higher fitness levels than both other groups and this remained significant when adjusted for age, sex and SES. Moderated regression analysis found that for the Shorter Term participation group, higher shuttle distance was associated with better visual-spatial working memory. Effect sizes were small though. Conclusion: We identified small and selective positive impact of participation in school based running programmes on fitness and cognition. While no long term benefit was identified for cognition or wellbeing, the impact on fitness and short term benefit suggest schools should consider participation.

14.
Hum Mutat ; 32(9): 1008-18, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21542061

RESUMEN

The ACTN3 R577X (rs1815739) genotype has been associated with athletic status and muscle phenotypes, although not consistently. Our objective was to conduct a meta-analysis of the published literature on athletic status and investigate its associations with physical capability in several new population-based studies. Relevant data were extracted from studies in the literature, comparing genotype frequencies between controls and sprint/power and endurance athletes. For life course physical capability, data were used from two studies of adolescents and seven studies in the Healthy Ageing across the Life Course (HALCyon) collaborative research program, involving individuals aged between 53 and 90+ years. We found evidence from the published literature to support the hypothesis that in Europeans the RR genotype is more common among sprint/power athletes compared with their controls. There is currently no evidence that the X allele is advantageous to endurance athleticism. We found no association between R577X and grip strength (P = 0.09, n = 7,672 in males; P = 0.90, n = 7,839 in females), standing balance, timed get up and go, or chair rises in our studies of physical capability. The ACTN3 R577X genotype is associated with sprint/power athletic status in Europeans, but does not appear to be associated with objective measures of physical capability in the general population.


Asunto(s)
Actinina/genética , Atletas , Resistencia Física/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
15.
J Clin Endocrinol Metab ; 106(10): 2979-2990, 2021 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-34111293

RESUMEN

CONTEXT: There is evidence demonstrating variation in insulin sensitivity across the menstrual cycle. However, to date, research has yielded inconsistent results. OBJECTIVE: This study investigated variation in insulin sensitivity across the menstrual cycle and associations with body mass index (BMI), physical activity, and cardiorespiratory fitness (CRF). METHODS: Data from 1906 premenopausal women in NHANES cycles 1999 to 2006 were analyzed. Menstrual cycle day was assessed using questionnaire responses recording days since last period. Rhythmic variation of plasma glucose, triglycerides, and insulin, homeostatic model of insulin resistance (HOMA-IR), and adipose tissue insulin resistance index (ADIPO-IR) across the menstrual cycle were analyzed using cosinor rhythmometry. Participants were assigned low or high categories of BMI, physical activity, and CRF, and category membership included in cosinor models as covariates. RESULTS: Rhythmicity was demonstrated by a significant cosine fit for glucose (P = .014) but not triglycerides (P = .369), insulin (P = .470), HOMA-IR (P = .461), and ADIPO-IR (P = .335). When covariates were included, rhythmicity was observed when adjusting for: 1) BMI: glucose (P < .001), triglycerides (P < .001), insulin (P < .001), HOMA-IR (P < .001), and ADIPO-IR (P < .001); 2) physical activity: glucose (P < .001), triglycerides (P = .006), and ADIPO-IR (P = .038); and 3) CRF: triglycerides (P = .041), insulin (P = .002), HOMA-IR (P = .004), and ADIPO-IR (P = .004). Triglyceride amplitude, but not acrophase, was greater in the high physical activity category compared to low (P = .018). CONCLUSION: Rhythmicity in insulin sensitivity and associated metabolites across the menstrual cycle are modified by BMI, physical activity, and CRF.


Asunto(s)
Índice de Masa Corporal , Ejercicio Físico/fisiología , Resistencia a la Insulina/fisiología , Ciclo Menstrual/fisiología , Aptitud Física/fisiología , Adulto , Estudios Transversales , Femenino , Humanos , Encuestas Nutricionales , Periodicidad
16.
J Vis Exp ; (175)2021 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-34633374

RESUMEN

Studies on adipose tissue are useful in understanding metabolic and other conditions. Human subcutaneous adipose tissue is accessible. With appropriate training and strict adherence to aseptic technique, subcutaneous adipose samples can be safely and efficiently obtained in a non-clinical setting by researchers. Following the administration of local anesthetic lateral to the umbilicus, a 14 G needle attached to a 5 or 10 mL syringe is inserted through the skin into the subcutaneous tissue. Under suction, the syringe is moved in a reciprocating, slicing motion to isolate fragments of adipose tissue. Withdrawing the plunger is enough to ensure that adipose tissue fragments are aspirated through the needle into the syringe. A single biopsy can collect about 200 mg of tissue. This biopsy technique is very safe for both participants and research staff. Following the biopsy, participants can resume most everyday activities, although they should avoid swimming and overly strenuous activities for 48 h to avoid excessive bleeding. Participants can safely undergo 2 biopsies within a single day, meaning that the technique can be applied in before-after acute intervention studies.


Asunto(s)
Lipectomía , Tejido Adiposo , Ejercicio Físico , Humanos , Grasa Subcutánea , Tejido Subcutáneo
17.
Physiol Rep ; 8(16): e14529, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32845565

RESUMEN

Understanding human physiological responses to high-fat energy excess (HFEE) may help combat the development of metabolic disease. We aimed to investigate the impact of manipulating the n-3PUFA content of HFEE diets on whole-body and skeletal muscle markers of insulin sensitivity. Twenty healthy males were overfed (150% energy, 60% fat, 25% carbohydrate, 15% protein) for 6 d. One group (n = 10) received 10% of fat intake as n-3PUFA rich fish oil (HF-FO), and the other group consumed a mix of fats (HF-C). Oral glucose tolerance tests with stable isotope tracer infusions were conducted before, and following, HFEE, with muscle biopsies obtained in basal and insulin-stimulated states for measurement of membrane phospholipids, ceramides, mitochondrial enzyme activities, and PKB and AMPKα2 activity. Insulin sensitivity and glucose disposal did not change following HFEE, irrespective of group. Skeletal muscle ceramide content increased following HFEE (8.5 ± 1.2 to 12.1 ± 1.7 nmol/mg, p = .03), irrespective of group. No change in mitochondrial enzyme activity was observed following HFEE, but citrate synthase activity was inversely associated with the increase in the ceramide content (r=-0.52, p = .048). A time by group interaction was observed for PKB activity (p = .003), with increased activity following HFEE in HF-C (4.5 ± 13.0mU/mg) and decreased activity in HF-FO (-10.1 ± 20.7 mU/mg) following HFEE. Basal AMPKα2 activity increased in HF-FO (4.1 ± 0.6 to 5.3 ± 0.7mU/mg, p = .049), but did not change in HF-C (4.6 ± 0.7 to 3.8 ± 0.9mU/mg) following HFEE. We conclude that early skeletal muscle signaling responses to HFEE appear to be modified by dietary n-3PUFA content, but the potential impact on future development of metabolic disease needs exploring.


Asunto(s)
Dieta Alta en Grasa/efectos adversos , Ácidos Grasos Omega-3/metabolismo , Hiperfagia/metabolismo , Músculo Esquelético/metabolismo , Quinasas de la Proteína-Quinasa Activada por el AMP , Adolescente , Adulto , Ceramidas/metabolismo , Humanos , Masculino , Estrés Oxidativo , Fosfolípidos/metabolismo , Proteínas Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo
18.
Cortex ; 45(1): 18-34, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19054505

RESUMEN

The genetically programmed courtship song of male Drosophila melanogaster has a rhythmic repetitive structure of sound pulses that is a critical component of mate recognition. This study investigates the neuronal basis of courtship song production by using the GAL4 enhancer trap paradigm to drive the expression of UASG-tetanus toxin (TNT) and UASG-transformer (tra) in subsets of cells. Of the 727 enhancer trap lines screened for courtship song defects in this way, 38 produced a phenotype, and these were used to drive the expression of Green Fluorescent Protein (GFP), thereby implicating the corresponding neuronal structures. Twelve of 13 lines which gave vigorous courtship but did not produce song, showed GFP expression in the mushroom bodies (MBs) and the giant descending neuronal tract and/or the larval interhemispheric junction (IJ). Furthermore, the relevant DNA in which the enhancer trap was inserted was isolated and sequenced in 27 of the lines, and a number of candidate genes that have been implicated in Ras and hedgehog signalling were identified. Other candidate genes that could plausibly affect courtship song were involved in mesothoracic or axonal development.


Asunto(s)
Comunicación Animal , Sistema Nervioso Central/fisiología , Conducta Sexual Animal/fisiología , Vocalización Animal/fisiología , Animales , Elementos Transponibles de ADN/genética , Drosophila melanogaster , Genómica , Proteínas Fluorescentes Verdes , Masculino , Mutagénesis Insercional , Fenotipo , Plásmidos/genética
20.
Br J Nutr ; 100(6): 1333-40, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18479585

RESUMEN

The aim of the present study was to investigate the interaction between the angiotensin-converting enzyme 1 (ACE) I/D polymorphism and energy and macronutrient intakes on adiposity-related phenotypes among toddlers and preschoolers. A representative sample of 2374 Greek children aged 1 to 5 years old was examined (Growth, Exercise and Nutrition Epidemiological Study in preSchoolers (GENESIS)). Dietary and anthropometric (i.e. BMI, waist circumference (WC)) assessments were carried out using standard procedures. DNA samples were obtained from 2102 children and were genotyped for the ACE I/D polymorphism. Among the entire population, 17 % were 'at risk of overweight' and a similar percentage were 'overweight'. The frequencies of the II, ID and DD genotypes were 16, 46 and 38 %, respectively. Significant interactions were found between the ACE I/D polymorphism and total energy intake on WC (P = 0.004 for interaction) and the ACE I/D polymorphism and protein intake on BMI and being overweight (P < 0.05 for interaction). Furthermore, it was found that the ACE I/D polymorphism may modify the effect of fat intake on WC and BMI, but this interaction disappeared after adjustment for additional potential confounders. Stratified analyses revealed that total energy is correlated with WC and protein intake is associated with BMI and being overweight only among carriers of the D-allele (i.e. DD or ID genotypes). These results suggest that the ACE I/D polymorphism may act as a modifying factor in the response of adiposity-related phenotypes to diet.


Asunto(s)
Adiposidad/genética , Fenómenos Fisiológicos Nutricionales Infantiles/genética , Ingestión de Energía/fisiología , Peptidil-Dipeptidasa A/genética , Adiposidad/fisiología , Antropometría/métodos , Índice de Masa Corporal , Fenómenos Fisiológicos Nutricionales Infantiles/fisiología , Preescolar , Dieta , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Femenino , Humanos , Lactante , Masculino , Fenotipo , Polimorfismo Genético
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