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1.
Am J Physiol Heart Circ Physiol ; 326(1): H123-H137, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37921669

RESUMEN

Vascular aging, featuring endothelial dysfunction and large elastic artery stiffening, is a major risk factor for the development of age-associated cardiovascular diseases (CVDs). Vascular aging is largely mediated by an excessive production of reactive oxygen species (ROS) and increased inflammation leading to reduced bioavailability of the vasodilatory molecule nitric oxide and remodeling of the arterial wall. Other cellular mechanisms (i.e., mitochondrial dysfunction, impaired stress response, deregulated nutrient sensing, cellular senescence), termed "hallmarks" or "pillars" of aging, may also contribute to vascular aging. Gonadal aging, which largely impacts women but also impacts some men, modulates the vascular aging process. Regular physical activity, including both aerobic and resistance exercise, is a first-line strategy for reducing CVD risk with aging. Although exercise is an effective intervention to counter vascular aging, there is considerable variation in the vascular response to exercise training with aging. Aerobic exercise improves large elastic artery stiffening in both middle-aged/older men and women and enhances endothelial function in middle-aged/older men by reducing oxidative stress and inflammation and preserving nitric oxide bioavailability; however, similar aerobic exercise training improvements are not consistently observed in estrogen-deficient postmenopausal women. Sex differences in adaptations to exercise may be related to gonadal aging and declines in estrogen in women that influence cellular-molecular mechanisms, disconnecting favorable signaling in the vasculature induced by exercise training. The present review will summarize the current state of knowledge on vascular adaptations to regular aerobic and resistance exercise with aging, the underlying mechanisms involved, and the moderating role of biological sex.


Asunto(s)
Enfermedades Cardiovasculares , Rigidez Vascular , Persona de Mediana Edad , Femenino , Humanos , Masculino , Anciano , Óxido Nítrico , Endotelio Vascular , Envejecimiento/fisiología , Ejercicio Físico/fisiología , Enfermedades Cardiovasculares/prevención & control , Inflamación , Estrógenos , Rigidez Vascular/fisiología
2.
Am J Physiol Heart Circ Physiol ; 327(3): H660-H665, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39058431

RESUMEN

Endothelial function declines with aging and independently predicts future cardiovascular disease (CVD) events. Diving also impairs endothelial function in humans. Yet, dolphins, being long-lived mammals adapted to diving, undergo repetitive cycles of tissue hypoxia-reoxygenation and disturbed shear stress without manifesting any apparent detrimental effects, as CVD is essentially nonexistent in these animals. Thus, dolphins may be a unique model of healthy arterial aging and may provide insights into strategies for clinical medicine. Emerging evidence shows that the circulating milieu (bioactive factors in the blood) is at least partially responsible for transducing reductions in age-related endothelial function. To assess whether dolphins have preserved endothelial function with aging because of a protected circulating milieu, we tested if the serum (pool of the circulating milieu) of bottlenose dolphins (Tursiops truncatus) induces the same arterial aging phenotype as the serum of age-equivalent humans. We incubated conduit arteries from young and old mice with dolphin and human serum and measured endothelial function ex vivo via endothelium-dependent dilation to acetylcholine. Although young arteries incubated with serum from midlife/older adult human serum had lower endothelial function, those incubated with dolphin serum consistently maintained high endothelial function regardless of the age of the donor. Thus, studying the arterial health of dolphins could lead to potential novel therapeutic strategies to improve age-related endothelial dysfunction in humans.NEW & NOTEWORTHY We demonstrate that, unlike serum of midlife/older adult humans, age-matched dolphin serum elicits higher endothelial function ex vivo in young mouse carotid arteries, suggesting that the circulating milieu of bottlenose dolphins may be geroprotective. We propose that dolphins are a novel model to investigate potential novel therapeutic strategies to mitigate age-related endothelial dysfunction in humans.


Asunto(s)
Delfín Mular , Endotelio Vascular , Vasodilatación , Animales , Masculino , Humanos , Endotelio Vascular/fisiopatología , Envejecimiento/fisiología , Modelos Animales , Femenino , Envejecimiento Saludable , Factores de Edad , Ratones Endogámicos C57BL , Vasodilatadores/farmacología , Arterias/fisiopatología
3.
Am J Physiol Heart Circ Physiol ; 326(5): H1279-H1290, 2024 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-38517225

RESUMEN

The circulating milieu, bioactive molecules in the bloodstream, is altered with aging and interfaces constantly with the vasculature. This anatomic juxtaposition suggests that circulating factors may actively modulate arterial function. Here, we developed a novel, translational experimental model that allows for direct interrogation of the influence of the circulating milieu on age-related arterial dysfunction (aortic stiffening and endothelial dysfunction). To do so, we exposed young and old mouse arteries to serum from young and old mice and young and midlife/older (ML/O) adult humans. We found that old mouse and ML/O adult human, but not young, serum stiffened young mouse aortic rings, assessed via elastic modulus (mouse and human serum, P = 0.003 vs. young serum control), and impaired carotid artery endothelial function, assessed by endothelium-dependent dilation (EDD) (mouse serum, P < 0.001; human serum, P = 0.006 vs. young serum control). Furthermore, young mouse and human, but not old, serum reduced aortic elastic modulus (mouse serum, P = 0.009; human serum, P < 0.001 vs. old/MLO serum control) and improved EDD (mouse and human serum, P = 0.015 vs. old/MLO serum control) in old arteries. In human serum-exposed arteries, in vivo arterial function assessed in the human donors correlated with circulating milieu-modulated arterial function in young mouse arteries (aortic stiffness, r = 0.634, P = 0.005; endothelial function, r = 0.609, P = 0.004) and old mouse arteries (aortic stiffness, r = 0.664, P = 0.001; endothelial function, r = 0.637, P = 0.003). This study establishes novel experimental approaches for directly assessing the effects of the circulating milieu on arterial function and implicates changes in the circulating milieu as a mechanism of in vivo arterial aging.NEW & NOTEWORTHY Changes in the circulating milieu with advancing age may be a mechanism underlying age-related arterial dysfunction. Ex vivo exposure of young mouse arteries to the circulating milieu from old mice or midlife/older adults impairs arterial function whereas exposure of old mouse arteries to the circulating milieu from young mice or young adults improves arterial function. These findings establish that the circulating milieu directly influences arterial function with aging.


Asunto(s)
Envejecimiento , Endotelio Vascular , Ratones Endogámicos C57BL , Rigidez Vascular , Vasodilatación , Animales , Humanos , Masculino , Adulto , Persona de Mediana Edad , Femenino , Endotelio Vascular/fisiopatología , Anciano , Factores de Edad , Ratones , Aorta/fisiopatología , Arterias Carótidas/fisiopatología , Adulto Joven , Módulo de Elasticidad
4.
Am J Physiol Heart Circ Physiol ; 324(6): H893-H904, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37115626

RESUMEN

The aorta stiffens with aging in both men and women, which predicts cardiovascular mortality. Aortic wall structural and extracellular matrix (ECM) remodeling, induced in part by chronic low-grade inflammation, contribute to aortic stiffening. Male mice are an established model of aortic aging. However, there is little information regarding whether female mice are an appropriate model of aortic aging in women, which we aimed to elucidate in the present study. We assessed two strains of mice and found that in C57BL/6N mice, in vivo aortic stiffness (pulse wave velocity, PWV) was higher with aging in both sexes, whereas in B6D2F1 mice, PWV was higher in old versus young male mice, but not in old versus young female mice. Because the age-related stiffening that occurs in men and women was reflected in male and female C57BL/6N mice, we examined the mechanisms of stiffening in this strain. In both sexes, aortic modulus of elasticity (pin myography) was lower in old mice, occurred in conjunction with and was related to higher plasma levels of the elastin-degrading enzyme matrix metalloproteinase-9 (MMP-9), and was accompanied by higher numbers of aortic elastin breaks and higher abundance of adventitial collagen-1. Plasma levels of the inflammatory cytokines interferon-γ, interleukin 6, and monocyte chemoattractant protein-1 were higher in both sexes of old mice. In conclusion, female C57BL/6N mice exhibit aortic stiffening, reduced modulus of elasticity and structural/ECM remodeling, and associated increases in MMP-9 and systemic inflammation with aging, and thus are an appropriate model of aortic aging in women.NEW & NOTEWORTHY Our study demonstrates that with aging, female C57BL/6N mice exhibit higher in vivo aortic stiffness, reduced modulus of elasticity, aortic wall structural and extracellular matrix remodeling, and elevations in systemic inflammation. These changes are largely reflective of those that occur with aging in women. Thus, female C57BL/6N mice are a viable model of human aortic aging and the utility of these animals should be considered in future biomedical investigations.


Asunto(s)
Elastina , Rigidez Vascular , Humanos , Animales , Ratones , Femenino , Masculino , Metaloproteinasa 9 de la Matriz , Análisis de la Onda del Pulso , Ratones Endogámicos C57BL , Aorta , Envejecimiento , Inflamación
5.
J Physiol ; 600(21): 4633-4651, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36111692

RESUMEN

Vascular dysfunction: develops progressively with ageing; increases the risk of cardiovascular diseases (CVD); and is characterized by endothelial dysfunction and arterial stiffening, which are primarily mediated by superoxide-driven oxidative stress and consequently reduced nitric oxide (NO) bioavailability and arterial structural changes. Interventions initiated before vascular dysfunction manifests may have more promise for reducing CVD risk than interventions targeting established dysfunction. Gut microbiome-derived trimethylamine N-oxide (TMAO) induces vascular dysfunction, is associated with higher CV risk, and can be suppressed by 3,3-dimethyl-1-butanol (DMB). We investigated whether DMB supplementation could prevent age-related vascular dysfunction in C57BL/6N mice when initiated prior to development of dysfunction. Mice received drinking water with 1% DMB or normal drinking water (control) from midlife (18 months) until being studied at 21, 24 or 27 months of age, and were compared to young adult (5 month) mice. Endothelial function [carotid artery endothelium-dependent dilatation (EDD) to acetylcholine; pressure myography] progressively declined with age in control mice, which was fully prevented by DMB via higher NO-mediated EDD and lower superoxide-related suppression of EDD (normalization of EDD with the superoxide dismutase mimetic TEMPOL). In vivo aortic stiffness (pulse wave velocity) increased progressively with age in controls, but DMB attenuated stiffening by ∼ 70%, probably due to preservation of endothelial function, as DMB did not affect aortic intrinsic mechanical (structural) stiffness (stress-strain testing) nor adventitial abundance of the arterial structural protein collagen. Our findings indicate that long-term DMB supplementation prevents/attenuates age-related vascular dysfunction, and therefore has potential for translation to humans for reducing CV risk with ageing. KEY POINTS: Vascular dysfunction, characterized by endothelial dysfunction and arterial stiffening, develops progressively with ageing and increases the risk of cardiovascular diseases (CVD). Interventions aimed at preventing the development of CV risk factors have more potential for preventing CVD relative to those aimed at reversing established dysfunction. The gut microbiome-derived metabolite trimethylamine N-oxide (TMAO) induces vascular dysfunction, is associated with higher CV risk and can be suppressed by supplementation with 3,3-dimethyl-1-butanol (DMB). In mice, DMB prevented the development of endothelial dysfunction and delayed and attenuated in vivo arterial stiffening with ageing when supplementation was initiated in midlife, prior to the development of dysfunction. DMB supplementation or other TMAO-suppressing interventions have potential for translation to humans for reducing CV risk with ageing.


Asunto(s)
Enfermedades Cardiovasculares , Agua Potable , Enfermedades Vasculares , Rigidez Vascular , Ratones , Humanos , Animales , Superóxidos/metabolismo , Vasodilatación , Análisis de la Onda del Pulso , Endotelio Vascular/metabolismo , Butanoles/metabolismo , Agua Potable/metabolismo , Ratones Endogámicos C57BL , Envejecimiento/metabolismo , Enfermedades Vasculares/metabolismo , Óxido Nítrico/metabolismo
6.
J Strength Cond Res ; 36(2): 386-391, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31868814

RESUMEN

ABSTRACT: Burnsed-Torres, ML, Wichmann, TK, Clayton, ZS, and Hahn, ME. Comparison of the Gauntlet test with standard laboratory measures of aerobic fitness. J Strength Cond Res 36(2): 386-391, 2022-The purpose of this study was to validate whether the Gauntlet test (GT) can accurately estimate individual aerobic endurance performance compared with standard laboratory-based physiological tests. The GT required athletes to complete 5 maximal effort running stages, with a 1-minute break between each stage, with the goal of achieving the best overall time. Eighteen men (n = 9) and women (n = 9) (age, 23.5 ± 4.13 years; body mass index, 23.1 ± 7.62 kg·m-2; 5k time, 22 ± 7 minutes; 10k time, 47 ± 15 minutes; V̇o2max, 52.3 ± 8 ml·kg-1·min-1) completed a lactate threshold test and V̇o2max test (laboratory measures). Four to 14 days later, subjects completed the GT on an outdoor track. Blood lactate (bLa), V̇o2max, and heart rate (HR) were recorded during the laboratory session. Blood lactate, HR, stage completion time, and overall completion time were recorded during the GT. Linear regression correlation analyses revealed a significant inverse association between V̇o2max (mL·kg-1·min-1) and GT completion time (r = -0.88, P < 0.0001). In addition, there were significant correlations between V̇o2max maximum HR and GT maximum HR (r = 0.89, P < 0.0001) and V̇o2max 3-minute post bLa and GT 3-minute post bLa (r = 0.63, P = 0.0029). Sex-specific analysis showed significant inverse associations between female and male GT completion time and V̇o2max (r = -0.70, P = 0.0352; r = -0.94, P < 0.0002). Bland-Altman plots were used to evaluate concordance between GT completion time, V̇o2max, maximum HR, and 3-minute post bLa. Results suggest the GT is a valid assessment to accurately estimate aerobic endurance performance similar to standard laboratory methods.


Asunto(s)
Laboratorios , Carrera , Adulto , Ejercicio Físico , Prueba de Esfuerzo , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Consumo de Oxígeno , Adulto Joven
7.
Nurs Crit Care ; 27(6): 838-848, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-34323346

RESUMEN

BACKGROUND: Enteral immunomodulatory nutrition is recommended as an adjuvant therapy for patients in intensive care units (ICU), but its effectiveness is incompletely understood. AIM: The aim of this review was to examine the effect of a commonly used immunomodulatory formula-omega-3 fatty acids, γ-linolenic acid, and antioxidants-on clinical outcomes and mortality risk in critically ill patients. DESIGN: Systematic review and meta-analysis of randomized controlled trials (RCTs). METHOD: PubMed, Scopus, and Institute for Scientific Information (ISI) Web of Knowledge databases were searched until 18 February 2021. RCTs that used the immunomodulatory formula in the ICU were included. RESULTS: Ten RCTs (1166 participants) were included in the meta-analysis. The immunomodulatory formula reduced the duration of ICU stay weighted mean difference [(WMD): -2.97 days; 95%CI: -5.59, -0.35)], mechanical ventilation (WMD = -2.20 days, 95%CI: -4.29, -0.10), sequential organ failure assessment and multiple organ dysfunction scores (Hedge's g: -0.42 U/L; 95% CI: -0.74, -0.11), decreased 8-day overall mortality risk (RR = 0.74, 95% CI: 0.58, 0.91), and extended the ICU-free days (WMD: 4.06 days, 95% CI: 0.02, 8.09). The improvement in respiratory function and reduction in mortality risk was more in patients with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). Furthermore, the reduction in mechanical ventilation and mortality risk was more evident in older (>60 years) vs young adults. CONCLUSION AND RELEVANCE TO CLINICAL PRACTICE: Taken together, the immunomodulatory formula may enhance clinical practice for critical care nurses, such that the prevalence and/or susceptibility to secondary conditions commonly encountered in the ICU (ie, ALI and ARDS) could be attenuated, ultimately allowing critical care nurses to focus their care on the primary reason for which a patient is in the ICU. The study protocol was registered in PROSPERO.


Asunto(s)
Enfermedad Crítica , Síndrome de Dificultad Respiratoria , Humanos , Anciano , Enfermedad Crítica/terapia , Cuidados Críticos , Nutrición Enteral/métodos , Respiración Artificial , Síndrome de Dificultad Respiratoria/terapia , Unidades de Cuidados Intensivos , Tiempo de Internación
8.
J Physiol ; 599(3): 911-925, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33103241

RESUMEN

KEY POINTS: The results of the present study establish the temporal pattern of age-related vascular dysfunction across the adult lifespan in sedentary mice consuming a non-Western diet, and the underlying mechanisms The results demonstrate that consuming a Western diet accelerates and exacerbates vascular ageing across the lifespan in sedentary mice They also show that lifelong voluntary aerobic exercise has remarkable protective effects on vascular function throughout the lifespan, in the setting of ageing alone, as well as ageing compounded by Western diet consumption Overall, the results indicate that amelioration of mitochondrial oxidative stress and inflammation are key mechanisms underlying the voluntary aerobic exercise-associated preservation of vascular function across the lifespan in both the presence and absence of a Western dietary pattern ABSTRACT: Advancing age is the major risk factor for cardiovascular diseases, driven largely by vascular endothelial dysfunction (impaired endothelium-dependent dilatation, EDD) and aortic stiffening (increased aortic pulse wave velocity, aPWV). In humans, vascular ageing occurs in the presence of differences in diet and physical activity, but the interactive effects of these factors are unknown. We assessed carotid artery EDD and aPWV across the lifespan in mice consuming standard (normal) low-fat chow (NC) or a high-fat/high-sucrose Western diet (WD) in the absence (sedentary, SED) or presence (voluntary wheel running, VWR) of aerobic exercise. Ageing impaired nitric oxide-mediated EDD (peak EDD 88 ± 12% 6 months P = 0.003 vs. 59 ± 9% 27 months NC-SED), which was accelerated by WD (60 ± 18% 6 months WD-SED). In NC mice, aPWV increased 32% with age (423 ± 13 cm/s at 24 months P < 0.001 vs. 321 ± 12 cm/s at 6 months) and absolute values were an additional ∼10% higher at any age in WD mice (P = 0.042 vs. NC-SED). Increases in aPWV with age in NC and WD mice were associated with 30-65% increases in aortic intrinsic wall stiffness (6 vs. 19-27 months, P = 0.007). Lifelong aerobic exercise prevented age- and WD-related vascular dysfunction across the lifespan, and this protection appeared to be mediated by mitigation of vascular mitochondrial oxidative stress and inflammation. Our results depict the temporal impairment of vascular function over the lifespan in mice, acceleration and exacerbation of that dysfunction with WD consumption, the remarkable protective effects of voluntary aerobic exercise, and the underlying mechanisms.


Asunto(s)
Dieta Occidental , Rigidez Vascular , Animales , Dieta Occidental/efectos adversos , Endotelio Vascular/metabolismo , Inflamación/metabolismo , Ratones , Actividad Motora , Estrés Oxidativo , Análisis de la Onda del Pulso
9.
Am J Physiol Heart Circ Physiol ; 321(1): H185-H196, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34114892

RESUMEN

We assessed the efficacy of oral supplementation with the flavanoid apigenin on arterial function during aging and identified critical mechanisms of action. Young (6 mo) and old (27 mo) C57BL/6N mice (model of arterial aging) consumed drinking water containing vehicle (0.2% carboxymethylcellulose; 10 young and 7 old) or apigenin (0.5 mg/mL in vehicle; 10 young and 9 old) for 6 wk. In vehicle-treated animals, isolated carotid artery endothelium-dependent dilation (EDD), bioassay of endothelial function, was impaired in old versus young (70% ± 9% vs. 92% ± 1%, P < 0.0001) due to reduced nitric oxide (NO) bioavailability. Old mice had greater arterial reactive oxygen species (ROS) production and oxidative stress (higher nitrotyrosine) associated with greater nicotinamide adenine dinucleotide phosphate oxidase (oxidant enzyme) and lower superoxide dismutase 1 and 2 (antioxidant enzymes); ex vivo administration of Tempol (antioxidant) restored EDD to young levels, indicating ROS-mediated suppression of EDD. Old animals also had greater aortic stiffness as indicated by higher aortic pulse wave velocity (PWV, 434 ± 9 vs. 346 ± 5 cm/s, P < 0.0001) due to greater intrinsic aortic wall stiffness associated with lower elastin levels and higher collagen, advanced glycation end products (AGEs), and proinflammatory cytokine abundance. In old mice, apigenin restored EDD (96% ± 2%) by increasing NO bioavailability, normalized arterial ROS, oxidative stress, and antioxidant expression, and abolished ROS inhibition of EDD. Moreover, apigenin prevented foam cell formation in vitro (initiating step in atherosclerosis) and mitigated age-associated aortic stiffening (PWV 373 ± 5 cm/s) by normalizing aortic intrinsic wall stiffness, collagen, elastin, AGEs, and inflammation. Thus, apigenin is a promising therapeutic for arterial aging.NEW & NOTEWORTHY Our study provides novel evidence that oral apigenin supplementation can reverse two clinically important indicators of arterial dysfunction with age, namely, vascular endothelial dysfunction and large elastic artery stiffening, and prevents foam cell formation in an established cell culture model of early atherosclerosis. Importantly, our results provide extensive insight into the biological mechanisms of apigenin action, including increased nitric oxide bioavailability, normalization of age-related increases in arterial ROS production and oxidative stress, reversal of age-associated aortic intrinsic mechanical wall stiffening and adverse remodeling of the extracellular matrix, and suppression of vascular inflammation. Given that apigenin is commercially available as a dietary supplement in humans, these preclinical findings provide the experimental basis for future translational studies assessing the potential of apigenin to treat arterial dysfunction and reduce cardiovascular disease risk with aging.


Asunto(s)
Envejecimiento/metabolismo , Endotelio Vascular/efectos de los fármacos , Inflamación/metabolismo , Estrés Oxidativo/efectos de los fármacos , Espirostanos/farmacología , Rigidez Vascular/efectos de los fármacos , Animales , Aorta/efectos de los fármacos , Aorta/metabolismo , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Arterias Carótidas/efectos de los fármacos , Arterias Carótidas/metabolismo , Endotelio Vascular/metabolismo , Ratones , Ratones Endogámicos C57BL , Especies Reactivas de Oxígeno/metabolismo
10.
J Sci Food Agric ; 101(10): 4003-4009, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33491232

RESUMEN

Increasing macular pigment optical density (MPOD) as a result of increased macular concentration of lutein and zeaxanthin may reduce the risk of age-related macular degeneration (AMD). The aim of the present study was to determine whether the consumption of eggs, a rich source of dietary lutein and zeaxanthin, influences MPOD and serum lutein. In this systematic review and meta-analysis we searched PubMed, Scopus, and ISI Web of Science up to July 2020, for relevant randomized clinical trials. Using a random-effects model, pooled weighted mean differences, and standard deviations (SDs) for each outcome were obtained. The quality of the eligible studies was assessed by the Cochrane Collaboration's tool. A meta-analysis of five trials (296 participants) revealed that egg consumption significantly increased MPOD (weighted mean differences (WMD): +0.037; 95% CI: 0.004, 0.069; P = 0.027) and serum lutein (WMD: +0.150 µmol L̂-1; 95% CI: 0.037, 0.263; P = 0.009). Subgroup analyses showed that egg consumption: (a) had a larger effect on MPOD in studies with a parallel design; and (b) increased serum lutein to a greater extent in a healthy population. We did not detect any heterogeneity between studies. Daily egg consumption has beneficial effects on MPOD and serum lutein is inversely associated with reduced AMD progression. Further clinical trials are required to confirm the results of this study. © 2021 Society of Chemical Industry.


Asunto(s)
Huevos/análisis , Pigmento Macular/metabolismo , Visión Ocular , Adulto , Anciano , Animales , Pollos , Femenino , Humanos , Luteína/análisis , Luteína/metabolismo , Pigmento Macular/análisis , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Zeaxantinas/análisis , Zeaxantinas/metabolismo
11.
Clin Sci (Lond) ; 134(12): 1491-1519, 2020 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-32584404

RESUMEN

Cardiovascular diseases (CVD) are the leading cause of death worldwide and aging is the primary risk factor for CVD. The development of vascular dysfunction, including endothelial dysfunction and stiffening of the large elastic arteries (i.e., the aorta and carotid arteries), contribute importantly to the age-related increase in CVD risk. Vascular aging is driven in large part by oxidative stress, which reduces bioavailability of nitric oxide and promotes alterations in the extracellular matrix. A key upstream driver of vascular oxidative stress is age-associated mitochondrial dysfunction. This review will focus on vascular mitochondria, mitochondrial dysregulation and mitochondrial reactive oxygen species (ROS) production and discuss current evidence for prevention and treatment of vascular aging via lifestyle and pharmacological strategies that improve mitochondrial health. We will also identify promising areas and important considerations ('research gaps') for future investigation.


Asunto(s)
Envejecimiento/fisiología , Vasos Sanguíneos/fisiología , Mitocondrias/metabolismo , Animales , Vasos Sanguíneos/fisiopatología , Humanos , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Rigidez Vascular
12.
Am J Physiol Endocrinol Metab ; 317(1): E172-E182, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31136202

RESUMEN

Polycystic ovary syndrome (PCOS) is associated with high rates of obesity and metabolic dysfunction. Repeated passive heat exposure (termed heat therapy) is a novel lifestyle intervention for improving health in obese women with PCOS. The purpose of this study was to examine changes in metabolic function in obese women with PCOS following heat therapy. Eighteen age- and BMI-matched obese women with PCOS (age: 27 ± 1 yr, BMI: 41.3 ± 1.1 kg/m-2) were assigned to heat therapy (HT) or time control (CON). HT participants underwent 30 one-hour hot tub sessions over 8-10 wk, while CON participants completed all testing but did not undergo heat therapy. Before (Pre), at the mid-point (Mid), and following (Post) 8-10 wk of heat therapy, metabolic health was assessed using a 2-h oral glucose tolerance test, a subcutaneous abdominal fat biopsy (Pre-Post only), and other blood markers relating to metabolic function. HT participants exhibited improved fasting glucose (Pre: 105 ± 3, Post: 89 ± 5mg/dl; P = 0.001), glucose area under the curve (AUC) (Pre: 18,698 ± 1,045, Post: 16,987 ± 1,017 mg·dl-1·min-1; P = 0.028) and insulin AUC (Pre: 126,924 ± 11,730, Post: 91,233 ± 14,429 IU l-1·min-1; P = 0.012). Adipocyte insulin signaling (p-AKT at Ser-473 with 1.2 nM insulin) increased in HT (Pre: 0.29 ± 0.14, Post: 0.93 ± 0.29 AU; P = 0.021). Additionally, serum testosterone declined in HT participants (Pre: 51 ± 7, Post: 34 ± 4 ng/dl; P = 0.033). No parameters changed over time in CON, and no change in BMI was observed in either group. HT substantially improved metabolic risk profile in obese women with PCOS. HT also reduced androgen excess and may improve PCOS symptomology.


Asunto(s)
Tejido Adiposo/metabolismo , Glucemia/metabolismo , Calor/uso terapéutico , Resistencia a la Insulina/fisiología , Insulina/metabolismo , Síndrome del Ovario Poliquístico/terapia , Adulto , Índice de Masa Corporal , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Inmersión , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/metabolismo , Obesidad/terapia , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/metabolismo
13.
Am J Physiol Heart Circ Physiol ; 327(1): H000, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38958689
14.
Am J Physiol Regul Integr Comp Physiol ; 315(4): R627-R637, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29791203

RESUMEN

Systemic insulin resistance and glucose intolerance occur with as little as 3 days of a high-fat diet (HFD) in mice and humans; the mechanisms that initiate acute insulin resistance are unknown. Most laboratories house mice at 22°C, which is below their thermoneutral temperature (~30°C). Cold stress has been shown to increase white adipose tissue (WAT) browning, alter lipid trafficking, and impair immune function, whereas energy intake and expenditure decrease with increasing ambient temperature; importantly, dysregulation of these parameters has been strongly linked to obesity-induced insulin resistance. Therefore, we compared acute changes in glucose metabolism and the metabolic phenotype in lean mice in response to a control diet or HFD housed at standard vivarium (22°C) and thermoneutral (30°C) temperatures. Glucose intolerance occurred following 1 or 5 days of HFD and was independent of housing temperature or adiposity; however, the reduction in tissue-specific glucose clearance with HFD diverged by temperature with reduced brown adipose tissue (BAT) glucose uptake at 22°C but reduced soleus glucose uptake at 30°C. Fasting glucose, food intake, and energy expenditure were significantly lower at 30°C, independent of diet. Additionally, markers of browning in both BAT and inguinal subcutaneous WAT, but not perigonadal epididymal WAT, decreased at 30°C. Together, we find housing temperature has a significant impact on the cellular pathways that regulate glucose tolerance in response to an acute HFD exposure. Thus, even short-term changes in housing temperature should be highly considered in interpretation of metabolic studies in mice.


Asunto(s)
Tejido Adiposo Pardo/metabolismo , Glucemia/metabolismo , Regulación de la Temperatura Corporal , Dieta Alta en Grasa , Metabolismo Energético , Intolerancia a la Glucosa/sangre , Vivienda para Animales , Grasa Subcutánea/metabolismo , Temperatura , Tejido Adiposo Pardo/fisiopatología , Animales , Biomarcadores/sangre , Ritmo Circadiano , Fosfatidilinositol 3-Quinasa Clase Ia/deficiencia , Fosfatidilinositol 3-Quinasa Clase Ia/genética , Modelos Animales de Enfermedad , Ingestión de Alimentos , Conducta Alimentaria , Intolerancia a la Glucosa/etiología , Intolerancia a la Glucosa/fisiopatología , Intolerancia a la Glucosa/psicología , Resistencia a la Insulina , Masculino , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Grasa Subcutánea/fisiopatología , Factores de Tiempo
18.
Adv Physiol Educ ; 40(3): 359-64, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27445286

RESUMEN

We investigated how students performed on weekly two-page laboratory reports based on whether the grading rubric was provided to the student electronically or in paper form and the inclusion of one- to two-sentence targeted comments. Subjects were registered for a 289-student, third-year human physiology class with laboratory and were randomized into four groups related to rubric delivery and targeted comments. All students received feedback via the same detailed grading rubric. At the end of the term, subjects provided consent and a self-assessment of their rubric viewing rate and preferences. There were no differences in laboratory report scores between groups (P = 0.86), although scores did improve over time (P < 0.01). Students receiving targeted comments self-reported viewing their rubric more often than students that received no comments (P = 0.02), but the viewing rate was independent of the rubric delivery method (P = 0.15). Subjects with high rubric viewing rates did not have higher laboratory report grades than subjects with low viewing rates (P = 0.64). When asked about their preference for the future, 43% of respondents preferred the same method again (electronic or paper rubric) and 25% had no preference. We conclude that although student laboratory report grades improved over time, the rate and degree of improvement were not related to rubric delivery method or to the inclusion of targeted comments.


Asunto(s)
Competencia Clínica/normas , Evaluación Educacional/métodos , Ciencia del Laboratorio Clínico/educación , Fisiología/educación , Estudiantes del Área de la Salud , Escritura/normas , Humanos , Distribución Aleatoria , Encuestas y Cuestionarios
20.
J Am Coll Nutr ; 34(2): 113-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25785868

RESUMEN

OBJECTIVE: Egg consumption is often discouraged due to cholesterol content; however, recent studies have not demonstrated a clear adverse influence of eggs on blood lipids. Furthermore, exercise training promotes improved lipids and blood pressure. The purpose of the study was to examine the effect of eating an isoenergetic (400 kcal) egg-based (including two eggs per day) versus bagel-based breakfasts, daily, combined with resistance training three times per week, prior to breakfast, on plasma lipids, glucose, insulin, insulin sensitivity and blood pressure in untrained individuals. METHODS: Twenty-five healthy adult men and women (18-35 years of age) participated in the twelve week study following random assignment to study groups. Lipids and blood pressure were examined at baseline and after 6 and 12 weeks. RESULTS: Plasma triglycerides (TG) decreased significantly in the egg- based breakfast (EBB) group from baseline to six weeks (p = 0.011) and from six to twelve weeks (p = 0.045). A significant (p = 0.033) decrease in insulin sensitivity was observed in the bagel-based breakfast (BBB) group from zero to six weeks. No significant effects on systolic blood pressure, diastolic blood pressure, total cholesterol, high density lipoprotein- cholesterol or low density lipoprotein cholesterol were detected. CONCLUSION: Overall, daily breakfasts including two eggs for twelve weeks did not adversely affect lipids during a resistance training program and promoted improvements in plasma TG.


Asunto(s)
Pan , Desayuno/fisiología , Huevos , Acondicionamiento Físico Humano/métodos , Entrenamiento de Fuerza , Adolescente , Adulto , Glucemia/análisis , Presión Sanguínea , Composición Corporal , Colesterol/sangre , Enfermedad Crónica , Dieta , Ingestión de Alimentos , Femenino , Humanos , Resistencia a la Insulina , Lípidos/sangre , Masculino , Distribución Aleatoria , Factores de Riesgo , Factores de Tiempo , Triglicéridos/sangre , Adulto Joven
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