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1.
JBMR Plus ; 7(5): e10732, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37197320

RESUMEN

C-type natriuretic peptide (CNP) is a paracrine growth factor essential in driving endochondral bone growth in mammals including humans. Despite evidence from animal experiments and tissues that CNP signaling stimulates osteoblast proliferation and osteoclast activity, whether CNP participates in bone remodeling in the mature skeleton is unknown. Using stored plasma samples from a previous randomized controlled clinical trial (RESHAW) of resveratrol supplementation in postmenopausal women exhibiting mild osteopenia, we have studied changes in plasma aminoterminal proCNP (NTproCNP) and concurrent change in bone turnover markers of formation (osteocalcin [OC] and alkaline phosphatase [ALP]) and resorption (C-terminal telopeptide type 1 collagen [CTX]) with bone mineral density (BMD) over a 2-year period of study in 125 subjects. In year one, subjects received placebo or resveratrol, switching to resveratrol or placebo, respectively, in year two. Across all time points, there were no significant associations of NTproCNP with CTX, ALP, or OC. During year one, plasma NTproCNP declined significantly in both groups. In the crossover comparison, analysis of change within individuals showed that, compared with placebo, NTproCNP declined after resveratrol (p = 0.011) and ALP increased (p = 0.008), whereas CTX and OC were unchanged. Inverse association of NTproCNP (r = -0.31; p = 0.025) and positive association of OC (r = 0.32, p = 0.022) with BMD at the lumbar spine were identified after resveratrol but not found after placebo. Decline in NTproCNP was independently associated with resveratrol treatment. This is the first evidence that CNP is modulated during a period of increasing BMD in postmenopausal women. Further study of NTproCNP and associations with drivers of bone formation or resorption can be expected to clarify CNP's role during other interventions directed to bone health in adults. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

2.
J Cereb Blood Flow Metab ; 41(3): 447-470, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32954902

RESUMEN

Derangements in cerebrovascular structure and function can impair cognitive performance throughout ageing and in cardiometabolic disease states, thus increasing dementia risk. Modifiable lifestyle factors that cause a decline in cardiometabolic health, such as physical inactivity, exacerbate these changes beyond those that are associated with normal ageing. The purpose of this review was to examine cerebrovascular, cognitive and neuroanatomical adaptations to ageing and the potential benefits of exercise training on these outcomes in adults 50 years or older. We systematically searched for cross-sectional or intervention studies that included exercise (aerobic, resistance or multimodal) and its effect on cerebrovascular function, cognition and neuroanatomical adaptations in this age demographic. The included studies were tabulated and described narratively. Aerobic exercise training was the predominant focus of the studies identified; there were limited studies exploring the effects of resistance exercise training and multimodal training on cerebrovascular function and cognition. Collectively, the evidence indicated that exercise can improve cerebrovascular function, cognition and neuroplasticity through areas of the brain associated with executive function and memory in adults 50 years or older, irrespective of their health status. However, more research is required to ascertain the mechanisms of action.


Asunto(s)
Envejecimiento , Encéfalo/fisiología , Cognición/fisiología , Ejercicio Físico , Animales , Estudios Transversales , Estado de Salud , Humanos , Consumo de Oxígeno , Entrenamiento de Fuerza
3.
Clin Nutr ; 40(3): 820-829, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32900519

RESUMEN

Ageing and menopause contribute to endothelial dysfunction, causing impaired cerebral perfusion, which is in turn associated with accelerated cognitive decline. In a 14-week pilot study, we showed that supplementation with low-dose resveratrol, a phytoestrogen that can enhance endothelial function, improved cerebrovascular and cognitive functions in postmenopausal women. We sought to confirm these benefits in a larger, longer-term trial. A 24-month randomized, placebo-controlled crossover trial was undertaken in 125 postmenopausal women, aged 45-85 years, who took 75 mg trans-resveratrol or placebo twice-daily for 12 months and then crossover to the alternative treatment for another 12 months. We evaluated within individual differences between each treatment period in measures of cognition (primary outcome), cerebrovascular function in the middle cerebral artery (cerebral blood flow velocity: CBFV, cerebrovascular responsiveness: CVR) and cardio-metabolic markers as secondary outcomes. Subgroup analyses examined effects of resveratrol by life stages. Compared to placebo, resveratrol supplementation resulted a significant 33% improvement in overall cognitive performance (Cohen's d = 0.170, P = 0.005). Women ≥65 years of age showed a relative improvement in verbal memory with resveratrol compared to those younger than 65 years. Furthermore, resveratrol improved secondary outcomes including resting mean CBFV (d = 0.275, P = 0.001), CVR to hypercapnia (d = 0.307, P = 0.027), CVR to cognitive stimuli (d = 0.259, P = 0.032), fasting insulin (d = 0.174, P = 0.025) and insulin resistance index (d = 0.102, P = 0.034). Regular supplementation with low-dose resveratrol can enhance cognition, cerebrovascular function and insulin sensitivity in postmenopausal women. This may translate into a slowing of the accelerated cognitive decline due to ageing and menopause, especially in late-life women. Further studies are warranted to observe whether these cognitive benefits of resveratrol can reduce the risk of dementia.


Asunto(s)
Fenómenos Fisiológicos Cardiovasculares , Cognición , Suplementos Dietéticos , Resistencia a la Insulina , Posmenopausia , Resveratrol/administración & dosificación , Anciano , Anciano de 80 o más Años , Circulación Cerebrovascular , Estudios Cruzados , Método Doble Ciego , Femenino , Envejecimiento Saludable , Humanos , Insulina/sangre , Memoria , Persona de Mediana Edad , Resveratrol/efectos adversos
4.
J Cereb Blood Flow Metab ; 41(5): 919-944, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33086920

RESUMEN

Previous studies have investigated whether migraine is a circulatory disorder, as migraineurs are at heightened risk of cerebrovascular disease. However, in most cases, systemic vascular function was evaluated, which may not reflect abnormalities in the cerebral circulation. Therefore, we aimed to determine whether cerebrovascular function differs between migraineurs and controls. A systematic literature search was conducted across three electronic databases to search for studies that compared cerebrovascular function in migraineurs to controls. Where applicable, meta-analyses were used to determine standardised mean differences (SMD) between migraineurs and controls. Seventy articles were identified, 40 of which contained quantitative data. Meta-analyses showed pulsatility index (PI) was higher (SMD = 0.23; 95%CI = 0.05 to 0.42, P = 0.01) and cerebrovascular responsiveness (CVR) to hypercapnia was lower (SMD=-0.34; 95%CI=-0.67 to -0.01, P = 0.04) in the posterior circulation of migraineurs, particularly those without aura. The meta-analyses also indicated that migraineurs have higher resting mean blood flow velocity in both anterior (SMD = 0.14; 95%CI = 0.05 to 0.23, P = 0.003) and posterior circulations (SMD = 0.20; 95%CI = 0.05 to 0.34, P = 0.007). Compared to healthy controls, migraineurs have altered cerebrovascular function, evidenced by elevated PI (representing arterial stiffness) and impaired CVR to hypercapnia (representing cerebral vasodilator function). Future studies should investigate whether improvement of cerebrovascular function is able to alleviate migraine.


Asunto(s)
Encéfalo/irrigación sanguínea , Circulación Cerebrovascular/fisiología , Trastornos Cerebrovasculares/fisiopatología , Trastornos Migrañosos/fisiopatología , Adulto , Velocidad del Flujo Sanguíneo/fisiología , Encéfalo/diagnóstico por imagen , Contencion de la Respiración , Estudios de Casos y Controles , Trastornos Cerebrovasculares/complicaciones , Trastornos Cerebrovasculares/diagnóstico , Femenino , Humanos , Hipercapnia/fisiopatología , Masculino , Trastornos Migrañosos/diagnóstico , Trastornos Migrañosos/prevención & control , Acoplamiento Neurovascular/fisiología , Flujo Pulsátil/fisiología , Ultrasonografía Doppler Transcraneal/métodos , Rigidez Vascular/fisiología , Vasodilatación/fisiología
5.
J Bone Miner Res ; 35(11): 2121-2131, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32564438

RESUMEN

Resveratrol, a naturally occurring polyphenol in red grapes and berries, can act as a phytoestrogen. It has been shown to improve both systemic and cerebral circulatory functions, possibly through activation of endothelial estrogen receptors. in vitro and in vivo studies in rodent models also indicate a bone-protective role for resveratrol, particularly in ovariectomized rat models that mimic postmenopausal osteoporosis caused by estrogen deficiency. Hypothesizing a circulatory benefit of resveratrol in bone tissue, we investigated whether resveratrol supplementation could improve bone health in postmenopausal women. The Resveratrol for Healthy Aging in Women (RESHAW) trial was a 24-month randomized, double-blind, placebo-controlled, two-period crossover intervention conducted to evaluate the effects of resveratrol (75 mg twice daily) on cognition, cerebrovascular function, bone health, cardiometabolic markers, and well-being in postmenopausal women. After 12 months of supplementation with resveratrol versus placebo, there were positive effects on bone density in the lumbar spine (+0.016 ± 0.003 g/cm2 ) and neck of femur (+0.005 ± 0.002 g/cm2 ), which were accompanied by a 7.24% reduction in C-terminal telopeptide type-1 collagen levels, a bone resorption marker, compared with placebo. The increase in bone mineral density in the femoral neck resulted in an improvement in T-score (+0.070 ± 0.018) and a reduction in the 10-year probability of major and hip fracture risk. The magnitude of improvement was higher in women with poor bone health biomarker status. Importantly, the improvement in femoral neck T-score with resveratrol correlated with improvement in perfusion. Our subanalysis also revealed that the bone-protective benefit of resveratrol was greater in participants who supplemented with vitamin D plus calcium. Regular supplementation with 75 mg of resveratrol twice daily has the potential to slow bone loss in the lumbar spine and femoral neck, common fracture sites in postmenopausal women without overt osteoporosis. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.


Asunto(s)
Densidad Ósea , Osteoporosis Posmenopáusica , Animales , Suplementos Dietéticos , Método Doble Ciego , Femenino , Cuello Femoral , Humanos , Posmenopausia , Ratas , Resveratrol/farmacología
7.
J Child Health Care ; 15(4): 299-311, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21828168

RESUMEN

Suboptimal omega-3 polyunsaturated fatty acid (n-3 PUFA) levels may contribute to attention deficit hyperactivity disorder (ADHD) and related developmental problems. Associations between n-3 and omega-6 (n-6) PUFA levels in red blood cells (erythrocytes) and learning and behaviour were investigated in 75 children aged 7-12 with ADHD. Children provided blood samples and underwent cognitive assessments. Parents completed questionnaires and Conners' Rating Scales. Controlling for covariates, higher n-3 PUFA predicted lower anxiety/shyness (ß = -.27), higher docosahexaenoic acid (DHA) better word reading (ß = .22), and higher n-6 PUFA poorer reading (ß = -.34), vocabulary (ß = .-.26), spelling (ß = -.30) and attention (ß = -.30). Thirty-six per cent of the sample with learning difficulties had lower DHA than those without (M = 3.26 ± 0.54 vs M = 3.68 ± 0.76, p = .02). This study is the first to compare erythrocyte PUFAs (a measure of PUFA status) in children who have ADHD with and without learning difficulties, and supports emerging indications that the former may be more likely responders to n-3 PUFAs.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/sangre , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Cognición , Ácidos Grasos Insaturados/sangre , Discapacidades para el Aprendizaje/etiología , Lectura , Niño , Eritrocitos , Femenino , Humanos , Masculino , Australia del Sur , Encuestas y Cuestionarios
8.
Int J Behav Nutr Phys Act ; 5: 53, 2008 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-18954466

RESUMEN

BACKGROUND: Sustainable lifestyle modification strategies are needed to address obesity and cardiovascular risk factors. Intensive, individualised programs have been successful, but are limited by time and resources. We have formulated a group-based lifestyle education program based upon national diet and physical activity (PA) recommendations to manage obesity and cardio-metabolic risk factors. This article describes the content and delivery of this program, with information on compliance and acceptability. METHODS: Overweight/obese adults (n = 153) with metabolic syndrome were recruited from the community and randomly allocated to intervention (INT) or control (CON). Written copies of Australian national dietary and PA guidelines were provided to all participants. INT took part in a 16-week lifestyle program which provided a curriculum and practical strategies on 1) dietary and PA information based on national guidelines, 2) behavioural self-management tools, 3) food-label reading, supermarkets tour and cooking, 4) exercise sessions, and 5) peer-group support. Compliance was assessed using attendance records and weekly food/PA logs. Participants' motivations, perceived benefits and goals were assessed through facilitated discussion. Program acceptability feedback was collected through structured focus groups. RESULTS: Although completion of weekly food/PA records was poor, attendance at information/education sessions (77% overall) and exercise participation (66% overall) was high, and compared with CON, multiple markers of body composition and cardio-metabolic health improved in INT. Participants reported that the most useful program components included food-label reading, cooking sessions, and learning new and different physical exercises, including home-based options. Participants also reported finding self-management techniques helpful, namely problem solving and short-term goal setting. The use of a group setting and supportive 'peer' leaders were found to be supportive. More frequent clinical assessment was suggested for future programs. CONCLUSION: This group-based lifestyle program achieved improvements in body composition and cardio-metabolic and physical fitness similar to individualised interventions which are more resource intensive to deliver. It confirmed that active training in lifestyle modification is more effective than passive provision of guidelines. Such programs should include social support and self-management techniques. Continued clinical follow up may be required for long-term maintenance in individuals attempting lifestyle behaviour change. Program facilitation by peers may help and should be further investigated in a community-based model.

9.
Curr Opin Lipidol ; 18(1): 25-30, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17218828

RESUMEN

PURPOSE OF REVIEW: This review summarizes evidence for metabolic health benefits of tree nuts and groundnuts (peanuts). While a role for nuts in the dietary management of LDL-cholesterol is well established, it is evident that regular consumption of nuts may also help to counteract other cardiovascular and metabolic risk factors. RECENT FINDINGS: Nuts are not only energy dense foods, they are rich sources of monounsaturated and polyunsaturated fatty acids and other bioactive nutrients with important metabolic effects. Contrary to expectations, epidemiological studies indicate that regular consumption of nuts is unlikely to contribute to obesity or increased risk of diabetes. In fact, it may help to regulate body weight by suppressing appetite and fat absorption. Nut consumption counteracts dyslipidemia and has the capacity to improve circulatory function through the actions of multiple constituents (arginine, polyphenols) on endothelial mechanisms. SUMMARY: Nuts are densely packaged nutrients with wide-ranging cardiovascular and metabolic benefits, which can be readily incorporated in healthy diets. Their potential role in counteracting obesity and the metabolic syndrome warrants further investigation.


Asunto(s)
Evaluación Nutricional , Nueces , Peso Corporal , Metabolismo Energético , Análisis de los Alimentos , Humanos , Lípidos/sangre , Nueces/química , Obesidad
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