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1.
JCI Insight ; 8(10)2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-37129980

RESUMEN

Elevated blood glucose levels, or hyperglycemia, can increase brain excitability and amyloid-ß (Aß) release, offering a mechanistic link between type 2 diabetes and Alzheimer's disease (AD). Since the cellular mechanisms governing this relationship are poorly understood, we explored whether ATP-sensitive potassium (KATP) channels, which couple changes in energy availability with cellular excitability, play a role in AD pathogenesis. First, we demonstrate that KATP channel subunits Kir6.2/KCNJ11 and SUR1/ABCC8 were expressed on excitatory and inhibitory neurons in the human brain, and cortical expression of KCNJ11 and ABCC8 changed with AD pathology in humans and mice. Next, we explored whether eliminating neuronal KATP channel activity uncoupled the relationship between metabolism, excitability, and Aß pathology in a potentially novel mouse model of cerebral amyloidosis and neuronal KATP channel ablation (i.e., amyloid precursor protein [APP]/PS1 Kir6.2-/- mouse). Using both acute and chronic paradigms, we demonstrate that Kir6.2-KATP channels are metabolic sensors that regulate hyperglycemia-dependent increases in interstitial fluid levels of Aß, amyloidogenic processing of APP, and amyloid plaque formation, which may be dependent on lactate release. These studies identify a potentially new role for Kir6.2-KATP channels in AD and suggest that pharmacological manipulation of Kir6.2-KATP channels holds therapeutic promise in reducing Aß pathology in patients with diabetes or prediabetes.


Asunto(s)
Enfermedad de Alzheimer , Diabetes Mellitus Tipo 2 , Hiperglucemia , Humanos , Ratones , Animales , Canales KATP/metabolismo , Enfermedad de Alzheimer/patología , Diabetes Mellitus Tipo 2/complicaciones , Glucosa , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo
2.
J Sports Sci ; 41(1): 56-62, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37012221

RESUMEN

Success in long-distance running relies on multiple factors including oxygen utilisation and lactate metabolism, and genetic associations with athlete status suggest elite competitors are heritably predisposed to superior performance. The Gly allele of the PPARGC1A Gly482Ser rs8192678 polymorphism has been associated with endurance athlete status and favourable aerobic training adaptations. However, the association of this polymorphism with performance amongst long-distance runners remains unclear. Accordingly, this study investigated whether rs8192678 was associated with elite status and competitive performance of long-distance runners. Genomic DNA from 656 Caucasian participants including 288 long-distance runners (201 men, 87 women) and 368 non-athletes (285 men, 83 women) was analysed. Medians of the 10 best UK times (Top10) for 10 km, half-marathon and marathon races were calculated, with all included athletes having personal best (PB) performances within 20% of Top10 (this study's definition of "elite"). Genotype and allele frequencies were compared between athletes and non-athletes, and athlete PB compared between genotypes. There were no differences in genotype frequency between athletes and non-athletes, but athlete Ser allele carriers were 2.5% faster than Gly/Gly homozygotes (p = 0.030). This study demonstrates that performance differences between elite long-distance runners are associated with rs8192678 genotype, with the Ser allele appearing to enhance performance.


Asunto(s)
Resistencia Física , Carrera , Masculino , Humanos , Femenino , Resistencia Física/genética , Polimorfismo Genético , Frecuencia de los Genes , Genotipo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética
3.
J Strength Cond Res ; 37(4): 799-805, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36763468

RESUMEN

ABSTRACT: Dines, HR, Nixon, J, Lockey, SJ, Herbert, AJ, Kipps, C, Pedlar, CR, Day, SH, Heffernan, SM, Antrobus, MR, Brazier, J, Erskine, RM, Stebbings, GK, Hall, ECR, and Williams, AG. Collagen gene polymorphisms previously associated with resistance to soft-tissue injury are more common in competitive runners than nonathletes. J Strength Cond Res 37(4): 799-805, 2023-Single-nucleotide polymorphisms (SNPs) of collagen genes have been associated with soft-tissue injury and running performance. However, their combined contribution to running performance is unknown. We investigated the association of 2 collagen gene SNPs with athlete status and performance in 1,429 Caucasian subjects, including 597 competitive runners (354 men and 243 women) and 832 nonathletes (490 men and 342 women). Genotyping for COL1A1 rs1800012 (C > A) and COL5A1 rs12722 (C > T) SNPs was performed by a real-time polymerase chain reaction. The numbers of "injury-resistant" alleles from each SNP, based on previous literature (rs1800012 A allele and rs12722 C allele), were combined as an injury-resistance score (RScore, 0-4; higher scores indicate injury resistance). Genotype frequencies, individually and combined as an RScore, were compared between cohorts and investigated for associations with performance using official race times. Runners had 1.34 times greater odds of being rs12722 CC homozygotes than nonathletes (19.7% vs. 15.5%, p = 0.020) with no difference in the rs1800012 genotype distribution ( p = 0.659). Fewer runners had an RScore 0 of (18.5% vs. 24.7%) and more had an RScore of 4 (0.6% vs. 0.3%) than nonathletes ( p < 0.001). Competitive performance was not associated with the COL1A1 genotype ( p = 0.933), COL5A1 genotype ( p = 0.613), or RScore ( p = 0.477). Although not associated directly with running performance among competitive runners, a higher combined frequency of injury-resistant COL1A1 rs1800012 A and COL5A1 rs12722 C alleles in competitive runners than nonathletes suggests these SNPs may be advantageous through a mechanism that supports, but does not directly enhance, running performance.


Asunto(s)
Carrera , Traumatismos de los Tejidos Blandos , Masculino , Humanos , Femenino , Colágeno Tipo V/genética , Genotipo , Colágeno/genética , Polimorfismo de Nucleótido Simple
4.
Eur J Sport Sci ; 23(5): 726-735, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35293840

RESUMEN

There is growing evidence of genetic contributions to tendon and ligament pathologies. Given the high incidence and severity of tendon and ligament injuries in elite rugby, we studied whether 13 gene polymorphisms previously associated with tendon/ligament injury were associated with elite athlete status. Participants from the RugbyGene project were 663 elite Caucasian male rugby athletes (RA) (mean (standard deviation) height 1.85 (0.07) m, mass 101 (12) kg, age 29 (7) yr), including 558 rugby union athletes (RU) and 105 rugby league athletes. Non-athletes (NA) were 909 Caucasian men and women (56% female; height 1.70 (0.10) m, mass 72 (13) kg, age 41 (23) yr). Genotypes were determined using TaqMan probes and groups compared using Χ2 and odds ratio (OR). COLGALT1 rs8090 AA genotype was more frequent in RA (27%) than NA (23%; P = 0.006). COL3A1 rs1800255 A allele was more frequent in RA (26%) than NA (23%) due to a greater frequency of GA genotype (39% vs 33%). For MIR608 rs4919510, RA had 1.7 times the odds of carrying the CC genotype compared to NA. MMP3 rs591058 TT genotype was less common in RA (25.1%) than NA (31.2%; P < 0.04). For NID1 rs4660148, RA had 1.6 times the odds of carrying the TT genotype compared to NA. It appears that elite rugby athletes have an inherited advantage that contributes to their elite status, possibly via resistance to soft tissue injury. These data may, in future, assist personalised management of injury risk amongst athletes.Highlights The elite rugby athletes we studied had differing genetic characteristics to non-athletes regarding genetic variants previously associated with soft-tissue injury risk.COLGALT1 rs8090, COL3A1 rs1800255, MIR608 rs4919510, MMP3 rs591058 and NID1 rs4660148 were all associated with elite status in rugby.We propose that elite rugby athletes might possess an inherited resistance to soft tissue injury, which has enabled them to achieve elite status despite exposure to the high-risk environment of elite rugby.


Asunto(s)
Fútbol Americano , MicroARNs , Traumatismos de los Tejidos Blandos , Humanos , Masculino , Femenino , Adulto , Metaloproteinasa 3 de la Matriz , Rugby , Alelos , Traumatismos de los Tejidos Blandos/genética
5.
Clin J Sport Med ; 33(5): e145-e151, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35350037

RESUMEN

OBJECTIVE: Concussions are common match injuries in elite rugby, and reports exist of reduced cognitive function and long-term health consequences that can interrupt or end a playing career and produce continued ill health. The aim of this study was to investigate the association between elite rugby status and 8 concussion-associated risk polymorphisms. We hypothesized that concussion-associated risk genotypes and alleles would be underrepresented in elite rugby athletes compared with nonathletes. DESIGN: A case-control genetic association study. SETTING: Institutional (university). PARTICIPANTS: Elite White male rugby athletes [n = 668, mean (SD) height 1.85 (0.07) m, mass 102 (12) kg, and age 29 (7) years] and 1015 nonathlete White men and women (48% men). INTERVENTIONS: Genotype was the independent variable, obtained by PCR of genomic DNA using TaqMan probes. MAIN OUTCOME MEASURE: Elite athlete status with groups compared using χ 2 and odds ratio (OR). RESULTS: The COMT rs4680 Met/Met (AA) genotype, Met allele possession, and Met allele frequency were lower in rugby athletes (24.8%, 74.6%, and 49.7%, respectively) than nonathletes (30.2%, 77.6%, and 54.0%; P < 0.05). The Val/Val (GG) genotype was more common in elite rugby athletes than nonathletes (OR 1.39, 95% confidence interval 1.04-1.86). No other polymorphism was associated with elite athlete status. CONCLUSIONS: Elite rugby athlete status is associated with COMT rs4680 genotype that, acting pleiotropically, could affect stress resilience and behavioral traits during competition, concussion risk, and/or recovery from concussion. Consequently, assessing COMT rs4680 genotype might aid future individualized management of concussion risk among athletes.


Asunto(s)
Conmoción Encefálica , Fútbol Americano , Humanos , Masculino , Femenino , Adulto , Rugby , Fútbol Americano/lesiones , Conmoción Encefálica/genética , Conmoción Encefálica/psicología , Polimorfismo Genético , Atletas , Catecol O-Metiltransferasa/genética
6.
Eur J Sport Sci ; 23(8): 1779-1788, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36503489

RESUMEN

Part 1 of this genetic association series highlighted several genetic variants independently associated with elite status in rugby. However, it is highly likely that the genetic influence on elite status is polygenic due to the interaction of multiple genes. Therefore, the aim of the present study was to investigate whether polygenic profiles of elite rugby athletes differed from non-athletes utilising 13 genetic polymorphisms previously associated with tendon/ligament injury. Total genotype score (TGS) was calculated and multifactor dimensionality reduction (MDR) was used to calculate SNP-SNP epistasis interactions. Based on our elite rugby data from Part 1, mean TGS was significantly higher in elite rugby athletes (52.1 ± 10.7) than non-athletes (48.7 ± 10.8). There were more elite rugby athletes (54%) within the upper TGS quartile, and fewer (46%) within the lower quartile, compared to non-athletes (31% and 69%, respectively; P = 5·10-5), and the TGS was able to distinguish between elite rugby athletes and non-athletes (area under the curve = 0.59; 95% confidence interval 0.55-0.63; P = 9·10-7). Furthermore, MDR identified a three-SNP model of COL5A1 rs12722, COL5A1 rs3196378 and MIR608 rs4919510 that was best able to predict elite athlete status, with a greater frequency of the CC-CC-CC genotype combination in elite rugby athletes (9.8%) than non-athletes (5.3%). We propose that elite rugby athletes possess "preferable" musculoskeletal soft-tissue injury-associated polygenic profiles that have helped them achieve success in the high injury risk environment of rugby. These data may, in future, have implications for the individual management of musculoskeletal soft-tissue injury.HighlightsElite rugby athletes have preferable polygenic profiles to non-athletes in terms of genetic variants previously associated with musculoskeletal soft-tissue injury.The total genotype score was able to distinguish between elite rugby athletes and non-athletes.COL5A1 rs12722, COL5A1 rs3196378 and MIR608 rs4919510 produced the best model for predicting elite athlete status.We propose that elite rugby athletes may have an inherited advantage to achieving elite status due to an increased resistance to soft-tissue injury.


Asunto(s)
MicroARNs , Rugby , Humanos , Genotipo , Atletas
7.
Neurobiol Dis ; 177: 105967, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36535550

RESUMEN

Epidemiological studies identified alcohol use disorder (AUD) as a risk factor for Alzheimer's disease (AD), yet there is conflicting evidence on how alcohol use promotes AD pathology. In this study, a 10-week moderate two-bottle choice drinking paradigm was used to identify how chronic ethanol exposure alters amyloid-ß (Aß)-related pathology, metabolism, and behavior. Ethanol-exposed APPswe/PSEN1dE9 (APP/PS1) mice showed increased brain atrophy and an increased number of amyloid plaques. Further analysis revealed that ethanol exposure led to a shift in the distribution of plaque size in the cortex and hippocampus. Ethanol-exposed mice developed a greater number of smaller plaques, potentially setting the stage for increased plaque proliferation in later life. Ethanol drinking APP/PS1 mice also exhibited deficits in nest building, a metric of self-care, as well as increased locomotor activity and central zone exploration in an open field test. Ethanol exposure also led to a diurnal shift in feeding behavior which was associated with changes in glucose homeostasis and glucose intolerance. Complementary in vivo microdialysis experiments were used to measure how acute ethanol directly modulates Aß in the hippocampal interstitial fluid (ISF). Acute ethanol transiently increased hippocampal ISF glucose levels, suggesting that ethanol directly affects cerebral metabolism. Acute ethanol also selectively increased ISF Aß40, but not ISF Aß42, levels during withdrawal. Lastly, chronic ethanol drinking increased N-methyl-d-aspartate receptor (NMDAR) and decreased γ-aminobutyric acid type-A receptor (GABAAR) mRNA levels, indicating a potential hyperexcitable shift in the brain's excitatory/inhibitory (E/I) balance. Collectively, these experiments suggest that ethanol may increase Aß deposition by disrupting metabolism and the brain's E/I balance. Furthermore, this study provides evidence that a moderate drinking paradigm culminates in an interaction between alcohol use and AD-related phenotypes with a potentiation of AD-related pathology, behavioral dysfunction, and metabolic impairment.


Asunto(s)
Enfermedad de Alzheimer , Animales , Ratones , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Modelos Animales de Enfermedad , Etanol/toxicidad , Glucosa/metabolismo , Hipocampo/metabolismo , Ratones Transgénicos , Placa Amiloide/metabolismo , Presenilina-1/genética , Presenilina-1/metabolismo
8.
Faraday Discuss ; 241(0): 341-356, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36254834

RESUMEN

Mechanochemical synthesis routes offer a sustainable, simple method for preparing materials. In this work, NiAl2O4 was synthesised by a mechanically activated method using a high-energy planetary mill and a calcination step. This study aims to identify the effect of different milling energies on the phases, chemical environments and surface composition of the material. In addition, it explores the thermal impact on the decomposition and structure of the materials. The materials were characterised by X-ray phosphorescence (XPS), solid-state UV-VIS (SS-UV-VIS), X-ray diffraction (XRD), nuclear magnetic resonance (NMR), high-resolution transmission electron microscopy (HR-TEM) and thermal gravimetry differential scanning calorimetry (TGA-DSC). A co-precipitated material is used as a reference along with the ground reagents which were used as a baseline. From this in-depth analysis of the material, a good understanding of the disordered partially inverse spinel structure is provided. This study has found that with calcination temperatures of 750 °C and 900 °C a mixed NiAl2O4 : NiO phase is produced with a Ni enriched surface. The surface is found to be relatively stable with the increase from 750 °C to 900 °C.

9.
Genes (Basel) ; 13(5)2022 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-35627205

RESUMEN

Due to the high-velocity collision-based nature of elite rugby league and union, the risk of sustaining a concussion is high. Occurrence of and outcomes following a concussion are probably affected by the interaction of multiple genes in a polygenic manner. This study investigated whether suspected concussion-associated polygenic profiles of elite rugby athletes differed from non-athletes and between rugby union forwards and backs. We hypothesised that a total genotype score (TGS) using eight concussion-associated polymorphisms would be higher in elite rugby athletes than non-athletes, indicating selection for protection against incurring or suffering prolonged effects of, concussion in the relatively high-risk environment of competitive rugby. In addition, multifactor dimensionality reduction was used to identify genetic interactions. Contrary to our hypothesis, TGS did not differ between elite rugby athletes and non-athletes (p ≥ 0.065), nor between rugby union forwards and backs (p = 0.668). Accordingly, the TGS could not discriminate between elite rugby athletes and non-athletes (AUC ~0.5), suggesting that, for the eight polymorphisms investigated, elite rugby athletes do not have a more 'preferable' concussion-associated polygenic profile than non-athletes. However, the COMT (rs4680) and MAPT (rs10445337) GC allele combination was more common in rugby athletes (31.7%; p < 0.001) and rugby union athletes (31.8%; p < 0.001) than non-athletes (24.5%). Our results thus suggest a genetic interaction between COMT (rs4680) and MAPT (rs10445337) assists rugby athletes in achieving elite status. These findings need exploration vis-à-vis sport-related concussion injury data and could have implications for the management of inter-individual differences in concussion risk.


Asunto(s)
Traumatismos en Atletas , Conmoción Encefálica , Herencia Multifactorial , Rugby , Atletas , Traumatismos en Atletas/genética , Conmoción Encefálica/genética , Humanos , Masculino , Rugby/lesiones
10.
Neuropsychopharmacology ; 47(6): 1256-1262, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-33854202

RESUMEN

While non-suicidal self-injury (NSSI) occurs in the general population at a surprisingly high rate, with higher rates among certain clinical  populations, its etiology is not well-understood. Consequently, the DSM-5 lists NSSI as requiring further research. This study utilizes a translational model of naturally-occurring NSSI to assess the role of early parental neglect and variation in the serotonin transporter genotype (5-HTT) in the etiology of NSSI. Subjects (N = 161) were rhesus macaques (Macaca mulatta) reared in one of three conditions (mother-reared (MR), peer-reared (PR), or surrogate peer-reared (SPR)), and classified as NSSI (n = 18) or non-NSSI (n = 143). Subjects were genotyped for 5-HTT and their behaviors were recorded during an ecologically-meaningful, stress-evoking, intruder paradigm. Two weeks prior to testing, blood samples were obtained and assayed for plasma cortisol and adrenocorticotropic hormone (ACTH) concentrations. NSSI subjects were more likely to be SPR, paralleling human studies showing that individuals that exhibit NSSI tend to have experienced abuse or neglect early in life. Results also indicated that variation in the 5-HTT genotype differentiated the NSSI subjects. NSSI subjects that were homozygous for the L allele exhibited high plasma ACTH and high rates of stress-induced stereotypies; whereas NSSI subjects with the s allele exhibited impulsive behaviors, including frequently approaching the potentially dangerous intruder, high rates of aggressive vocal threats, and more activity. These results suggest that there may be different 5-HTT genotype-mediated NSSI typologies and that both early experiences and variation in the 5-HTT genotype may be important factors in understanding the etiology of NSSI.


Asunto(s)
Conducta Autodestructiva , Proteínas de Transporte de Serotonina en la Membrana Plasmática , Hormona Adrenocorticotrópica , Animales , Genotipo , Humanos , Macaca mulatta/genética , Conducta Autodestructiva/genética , Serotonina , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética
11.
Angew Chem Int Ed Engl ; 60(44): 23878-23884, 2021 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-34464506

RESUMEN

A combination of charge density studies and solid state nuclear magnetic resonance (NMR) 1 JNC coupling measurements supported by periodic density functional theory (DFT) calculations is used to characterise the transition from an n-π* interaction to bond formation between a nucleophilic nitrogen atom and an electrophilic sp2 carbon atom in a series of crystalline peri-substituted naphthalenes. As the N⋅⋅⋅C distance reduces there is a sharp decrease in the Laplacian derived from increasing charge density between the two groups at ca. N⋅⋅⋅C = 1.8 Å, with the periodic DFT calculations predicting, and heteronuclear spin-echo NMR measurements confirming, the 1 JNC couplings of ≈3-6 Hz for long C-N bonds (1.60-1.65 Å), and 1 JNC couplings of <1 Hz for N⋅⋅⋅C >2.1 Å.

12.
Int J Sports Physiol Perform ; 16(12): 1858-1864, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34088882

RESUMEN

PURPOSE: Genetic polymorphisms have been associated with the adaptation to training in maximal oxygen uptake (V˙O2max). However, the genotype distribution of selected polymorphisms in athletic cohorts is unknown, with their influence on performance characteristics also undetermined. This study investigated whether the genotype distributions of 3 polymorphisms previously associated with V˙O2max training adaptation are associated with elite athlete status and performance characteristics in runners and rugby athletes, competitors for whom aerobic metabolism is important. METHODS: Genomic DNA was collected from 732 men including 165 long-distance runners, 212 elite rugby union athletes, and 355 nonathletes. Genotype and allele frequencies of PRDM1 rs10499043 C/T, GRIN3A rs1535628 G/A, and KCNH8 rs4973706 T/C were compared between athletes and nonathletes. Personal-best marathon times in runners, as well as in-game performance variables and playing position, of rugby athletes were analyzed according to genotype. RESULTS: Runners with PRDM1 T alleles recorded marathon times ∼3 minutes faster than CC homozygotes (02:27:55 [00:07:32] h vs 02:31:03 [00:08:24] h, P = .023). Rugby athletes had 1.57 times greater odds of possessing the KCNH8 TT genotype than nonathletes (65.5% vs 54.7%, χ2 = 6.494, P = .013). No other associations were identified. CONCLUSIONS: This study is the first to demonstrate that polymorphisms previously associated with V˙O2max training adaptations in nonathletes are also associated with marathon performance (PRDM1) and elite rugby union status (KCNH8). The genotypes and alleles previously associated with superior endurance-training adaptation appear to be advantageous in long-distance running and achieving elite status in rugby union.


Asunto(s)
Rendimiento Atlético , Carrera , Atletas , Humanos , Masculino , Carrera de Maratón , Consumo de Oxígeno/genética , Polimorfismo Genético , Rugby
13.
Sports (Basel) ; 9(2)2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33499151

RESUMEN

Elite rugby league and union have some of the highest reported rates of concussion (mild traumatic brain injury) in professional sport due in part to their full-contact high-velocity collision-based nature. Currently, concussions are the most commonly reported match injury during the tackle for both the ball carrier and the tackler (8-28 concussions per 1000 player match hours) and reports exist of reduced cognitive function and long-term health consequences that can end a playing career and produce continued ill health. Concussion is a complex phenotype, influenced by environmental factors and an individual's genetic predisposition. This article reviews concussion incidence within elite rugby and addresses the biomechanics and pathophysiology of concussion and how genetic predisposition may influence incidence, severity and outcome. Associations have been reported between a variety of genetic variants and traumatic brain injury. However, little effort has been devoted to the study of genetic associations with concussion within elite rugby players. Due to a growing understanding of the molecular characteristics underpinning the pathophysiology of concussion, investigating genetic variation within elite rugby is a viable and worthy proposition. Therefore, we propose from this review that several genetic variants within or near candidate genes of interest, namely APOE, MAPT, IL6R, COMT, SLC6A4, 5-HTTLPR, DRD2, DRD4, ANKK1, BDNF and GRIN2A, warrant further study within elite rugby and other sports involving high-velocity collisions.

14.
J Sports Med Phys Fitness ; 61(11): 1490-1498, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33480513

RESUMEN

BACKGROUND: The aim of the study was to establish the bone and body composition characteristics of high-level athletes with and without a history of stress fracture injury. METHODS: Overall, 279 high-level athletes (212 men, 67 women) (age 28.0±9.2 years; body mass 75.0±17.4 kg; height 1.78±0.10 m) and 112 non-athletic controls (60 women, 52 men) 36.2±15.0 years; 70.9±12.9 kg; 1.71±0.10 m) were assessed by DXA to establish their bone mineral density and content, body fat and lean mass. Athletes completed a questionnaire detailing their stress fracture history. RESULTS: There were no differences in whole-body bone mineral density (men 1.41±0.12 g/cm2, women 1.19±0.09 g/cm2), bone mineral content (men 3709±626 g, women 2263±290 g), body fat (men 16.3±5.0%,women 23.0±4.6%) and lean mass (men 65.4±9.9 kg, women 38.7±3.6 kg) between athletes with a history of stress fracture (34 men, 16 women) and those without (176 men, 40 women). CONCLUSIONS: DXA derived bone and body composition characteristics were not independent risk factors for stress fracture injury in high-level athletes. This study in a large cohort of high-level athletes provides normative bone and body composition values that can be used as a benchmark for researchers and applied practitioners.


Asunto(s)
Fracturas por Estrés , Absorciometría de Fotón , Adolescente , Adulto , Atletas , Composición Corporal , Densidad Ósea , Femenino , Fracturas por Estrés/diagnóstico por imagen , Humanos , Masculino , Adulto Joven
15.
Neurobiol Stress ; 13: 100254, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33344709

RESUMEN

Persistent psychological stress increases the risk of many chronic diseases of aging. Little progress has been made to effectively reduce stress responses or mitigate stress effects suggesting a need for better understanding of factors that influence stress responses. Limited evidence suggests that diet may be a factor in modifying the effects of stress. However, long-term studies of diet effects on stress reactive systems are not available, and controlled randomized clinical trials are difficult and costly. Here we report the outcomes of a controlled, randomized preclinical trial of the effects of long-term consumption (31 months, ~ equivalent to 9 human years) of Western versus Mediterranean - like diets on behavioral and physiological responses to acute (brief social separation) and chronic (social subordination) psychosocial stress in 38 adult, socially-housed, female cynomolgus macaques. Compared to animals fed a Western diet, those fed the Mediterranean diet exhibited enhanced stress resilience as indicated by lower sympathetic activity, brisker and more overt heart rate responses to acute stress, more rapid recovery, and lower cortisol responses to acute psychological stress and adrenocorticotropin (ACTH) challenge. Furthermore, age-related increases in sympathetic activity and cortisol responses to stress were delayed by the Mediterranean diet. Population level diet modification in humans has been shown to be feasible. Our findings suggest that population-wide adoption of a Mediterranean-like diet pattern may provide a cost-effective intervention on psychological stress and promote healthy aging with the potential for widespread efficacy.

16.
Phys Chem Chem Phys ; 22(6): 3400-3413, 2020 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-31984388

RESUMEN

A combined multinuclear solid state NMR and gauge included projected augmented wave, density functional theory (GIPAW DFT) computational approach is evaluated to determine the four heteronuclear 1J(13C,17O) couplings in solid 17O enriched naphthalaldehydic acid. Direct multi-field 17O magic angle spinning (MAS), triple quantum MAS (3QMAS) and double rotation (DOR) experiments are initially utilised to evaluate the accuracy of the DFT approximations used in the calculation of the isotropic chemical shifts (δiso), quadrupole coupling constants (CQ) and asymmetry (ηQ) parameters. These combined approaches give δiso values of 313, 200 and 66 ppm for the carbonyl (C[double bond, length as m-dash]O), ether (-O-) and hydroxyl (-OH) environments, respectively, with the corresponding measured quadrupole products (PQ) being 8.2, 9.0 and 10.6 MHz. The geometry optimised DFT structure derived using the CASTEP code gives firm agreement with the shifts observed for the ether (δiso = 223, PQ = 9.4 MHz) and hydroxyl (δiso = 62, PQ = 10.5 MHz) environments but the unoptimised experimental XRD structure has better agreement for the carbonyl group (δiso = 320, PQ = 8.3 MHz). The determined δiso and ηQ values are shown to be consistent with bond lengths closer to 1.222 Å (experimental length) rather than the geometry optimised length of 1.238 Å. The geometry optimised DFT 1J(13C,17O) coupling to the hydroxyl is calculated as 20 Hz and the couplings to the ether were calculated to be 37 (O-C[double bond, length as m-dash]O) and 32 (O-C-OH) Hz. The scalar coupling parameters for the unoptimised experimental carbonyl group predict a 1J(13C,17O) value of 28 Hz, whilst optimisation gives a value of 27 Hz. These calculated 1J(13C,17O) couplings, together with estimations of the probability of each O environment being isotopically labelled (determined by electrospray ionisation mass spectrometry) and the measured refocussable transverse dephasing (T2') behaviour, are combined to simulate the experimental decay behaviour. Good agreement between the measured and calculated decay behaviour is observed.

17.
J Strength Cond Res ; 34(6): 1790-1801, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30138238

RESUMEN

Brazier, J, Antrobus, M, Stebbings, GK, Day, SH, Callus, P, Erskine, RM, Bennett, MA, Kilduff, LP, and Williams, AG. Anthropometric and physiological characteristics of elite male rugby athletes. J Strength Cond Res 34(6): 1790-1801, 2020-This is the first article to review the anthropometric and physiological characteristics required for elite rugby performance within both rugby union (RU) and rugby league (RL). Anthropometric characteristics such as height and body mass, and physiological characteristics such as speed and muscular strength, have previously been advocated as key discriminators of playing level within rugby. This review aimed to identify the key anthropometric and physiological properties required for elite performance in rugby, distinguishing between RU and RL, forwards and backs and competitive levels. There are differences between competitive standards such that, at the elite level, athletes are heaviest (RU forwards ∼111 kg, backs ∼93 kg; RL forwards ∼103 kg, backs ∼90 kg) with lowest % body fat (RU forwards ∼15%, backs ∼12%; RL forwards ∼14%, backs ∼11%), they have most fat-free mass and are strongest (back squat: RU forwards ∼176 kg, backs ∼157 kg; RL forwards ∼188 kg, backs ∼168 kg; bench press: RU forwards ∼131 kg, backs ∼118 kg; RL forwards ∼122 kg, backs ∼113 kg) and fastest (10 m: RU forwards ∼1.87 seconds, backs ∼1.77 seconds; 10 m: RL forwards ∼1.9 seconds, backs ∼1.83 seconds). We also have unpublished data that indicate contemporary RU athletes have less body fat and are stronger and faster than the published data suggest. Regardless, well-developed speed, agility, lower-body power, and strength characteristics are vital for elite performance, probably reflect both environmental (training, diet, etc.) and genetic factors, distinguish between competitive levels, and are therefore important determinants of elite status in rugby.


Asunto(s)
Pesos y Medidas Corporales , Fútbol Americano/fisiología , Aptitud Física/fisiología , Atletas , Rendimiento Atlético/fisiología , Humanos , Masculino , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología
18.
Front Neurosci ; 13: 843, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31555072

RESUMEN

Epidemiological studies suggest that individuals with type 2 diabetes (T2D) have a twofold to fourfold increased risk for developing Alzheimer's disease (AD), however, the exact mechanisms linking the two diseases are unknown. In both conditions, the majority of pathophysiological changes, including glucose and insulin dysregulation, insulin resistance, and AD-related changes in Aß and tau, occur decades before the onset of clinical symptoms and diagnosis. In this study, we investigated the relationship between metabolic biomarkers associated with T2D and amyloid pathology including Aß levels, from cerebrospinal fluid (CSF) and fasting plasma of healthy, pre-diabetic (PreD), and T2D vervet monkeys (Chlorocebus aethiops sabaeus). Consistent with the human disease, T2D monkeys have increased plasma and CSF glucose levels as they transition from normoglycemia to PreD and diabetic states. Although plasma levels of acylcarnitines and amino acids remained largely unchanged, peripheral hyperglycemia correlated with decreased CSF acylcarnitines and CSF amino acids, including branched chain amino acid (BCAA) concentrations, suggesting profound changes in cerebral metabolism coincident with systemic glucose dysregulation. Moreover, CSF Aß 40 and CSF Aß 42 levels decreased in T2D monkeys, a phenomenon observed in the human course of AD which coincides with increased amyloid deposition within the brain. In agreement with previous studies in mice, CSF Aß 40 and CSF Aß 42 were highly correlated with CSF glucose levels, suggesting that glucose levels in the brain are associated with changes in Aß metabolism. Interestingly, CSF Aß 40 and CSF Aß 42 levels were also highly correlated with plasma but not CSF lactate levels, suggesting that plasma lactate might serve as a potential biomarker of disease progression in AD. Moreover, CSF glucose and plasma lactate levels were correlated with CSF amino acid and acylcarnitine levels, demonstrating alterations in cerebral metabolism occurring with the onset of T2D. Together, these data suggest that peripheral metabolic changes associated with the development of T2D produce alterations in brain metabolism that lead to early changes in the amyloid cascade, similar to those observed in pre-symptomatic AD.

19.
Sports (Basel) ; 7(6)2019 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-31167482

RESUMEN

This article reviews tendon and ligament injury incidence and severity within elite rugby union and rugby league. Furthermore, it discusses the biological makeup of tendons and ligaments and how genetic variation may influence this and predisposition to injury. Elite rugby has one of the highest reported injury incidences of any professional sport. This is likely due to a combination of well-established injury surveillance systems and the characteristics of the game, whereby high-impact body contact frequently occurs, in addition to the high intensity, multispeed and multidirectional nature of play. Some of the most severe of all these injuries are tendon and ligament/joint (non-bone), and therefore, potentially the most debilitating to a player and playing squad across a season or World Cup competition. The aetiology of these injuries is highly multi-factorial, with a growing body of evidence suggesting that some of the inter-individual variability in injury susceptibility may be due to genetic variation. However, little effort has been devoted to the study of genetic injury traits within rugby athletes. Due to a growing understanding of the molecular characteristics underpinning the aetiology of injury, investigating genetic variation within elite rugby is a viable and worthy proposition. Therefore, we propose several single nucleotide polymorphisms within candidate genes of interest; COL1A1, COL3A1, COL5A1, MIR608, MMP3, TIMP2, VEGFA, NID1 and COLGALT1 warrant further study within elite rugby and other invasion sports.

20.
eNeuro ; 6(2)2019.
Artículo en Inglés | MEDLINE | ID: mdl-31040160

RESUMEN

Currently there is no effective therapy available for cognitive impairments in Down syndrome (DS), one of the most prevalent forms of intellectual disability in humans associated with the chromosomes 21 trisomy. Glucagon-like peptide-1 (GLP-1) is an incretin hormone that maintains glucose homeostasis by stimulating insulin secretion. Its natural cleavage product GLP-1 (9-36) lacks insulinotropic effects and has a low binding affinity for GLP-1 receptors; thus, GLP-1 (9-36) has historically been identified as an inactive metabolite. Conversely, recent work has demonstrated interesting physiological properties of GLP-1 (9-36) such as cardioprotection and neuroprotection. We have previously shown that GLP-1 (9-36) administration enhances neuronal plasticity in young WT mice and ameliorates cognitive deficits in a mouse model of Alzheimer's disease. Here, we report that systemic administration of GLP-1 (9-36) in Ts65Dn DS model mice of either sex resulted in decreased mitochondrial oxidative stress in hippocampus and improved dendritic spine morphology, increase of mature spines and reduction of immature spines. Importantly, these molecular alterations translated into functional changes in that long-term potentiation failure and cognitive impairments in TsDn65 DS model mice were rescued with GLP-1 (9-36) treatment. We also show that chronic GLP-1 (9-36) treatment did not alter glucose tolerance in either WT or DS model mice. Our findings suggest that GLP-1 (9-36) treatment may have therapeutic potential for DS and other neurodegenerative diseases associated with increased neuronal oxidative stress.


Asunto(s)
Reacción de Prevención/efectos de los fármacos , Disfunción Cognitiva/tratamiento farmacológico , Espinas Dendríticas/efectos de los fármacos , Síndrome de Down/tratamiento farmacológico , Péptido 1 Similar al Glucagón/análogos & derivados , Hipocampo/efectos de los fármacos , Potenciación a Largo Plazo/efectos de los fármacos , Plasticidad Neuronal/efectos de los fármacos , Nootrópicos/farmacología , Estrés Oxidativo/efectos de los fármacos , Memoria Espacial/efectos de los fármacos , Animales , Conducta Animal/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Péptido 1 Similar al Glucagón/administración & dosificación , Péptido 1 Similar al Glucagón/farmacología , Prueba de Tolerancia a la Glucosa , Masculino , Ratones , Ratones Transgénicos , Nootrópicos/administración & dosificación
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