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1.
Food Funct ; 12(24): 12526-12534, 2021 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-34812466

RESUMEN

Postmenopausal women experience an increase in bone remodeling with the rate of bone resorption superseding the rate of bone formation. This results in a net bone loss with a subsequent increased risk for osteoporosis and fractures. High blood pressure (BP) has been associated with loss of bone mineral density and increased propensity to fractures. Strawberries are rich in polyphenols, which have been shown to have anti-hypertensive and bone-protective properties. Thus, we examined whether daily intake of strawberries would positively affect biomarkers of bone metabolism in postmenopausal women with pre- and stage 1-hypertension. Participants (age: 59 ± 6 years; body mass index: 31.5 ± 4.1 kg m-2; systolic BP: 140 ± 13 mmHg) were randomly assigned to consume (1) 50 g of freeze-dried strawberry powder (FDSP), (2) 25 g FDSP + 25 g of placebo powder, or (3) 50 g placebo powder for eight weeks. Results indicate a significant time-by-treatment interaction (P = 0.04) for serum insulin-like growth factor (IGF)-1, a hormone that plays a major role in bone formation. Serum concentrations of bone-specific alkaline phosphatase, a marker of bone formation, and tartrate-resistant acid phosphatase-5b, a specific marker of bone resorption, were not affected by FDSP compared to placebo. Although not statistically significant, after eight weeks, osteocalcin increased in the 50 g FDSP group with a large effect size (d = 0.6) when compared to the placebo-control group. Adiponectin increased by 5% and 6% in the 25 g and 50 g FDSP groups, respectively, while it declined in the placebo-control group by 25% (P = 0.03 for time-by-treatment interaction). Our findings suggest that consumption of 25 g FDSP increases IGF-1 in postmenopausal women with pre- and stage 1-hypertension. However, further studies are needed to assert the effectiveness of a strawberry intervention for bone health.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Fragaria , Hipertensión/tratamiento farmacológico , Osteoporosis Posmenopáusica/prevención & control , Extractos Vegetales/farmacología , Polifenoles/farmacología , Anciano , Biomarcadores/sangre , Resorción Ósea/sangre , Resorción Ósea/tratamiento farmacológico , Femenino , Humanos , Hipertensión/sangre , Hipertensión/complicaciones , Persona de Mediana Edad , Osteoporosis Posmenopáusica/sangre , Osteoporosis Posmenopáusica/complicaciones , Extractos Vegetales/sangre , Polifenoles/sangre , Posmenopausia
2.
J Med Food ; 23(12): 1238-1247, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32429737

RESUMEN

Greater than one-third of adults in the United States have metabolic syndrome (MetS), a cluster of risk factors highly associated with the development of cardiovascular diseases. Premature vascular dysfunction in MetS may lead to accelerated age-related atherogenesis and arterial stiffening, thereby increasing cardiovascular risk. Montmorency tart cherries (Prunus cerasus L.) are rich in bioactive compounds, such as anthocyanins, known to exert cardiovascular protective effects. Previous research suggests that tart cherry juice consumption may improve cardiovascular health. The objective of this study was to evaluate the effects of daily consumption of tart cherry juice on hemodynamics, arterial stiffness, and blood biomarkers of cardiovascular and metabolic health in men and women with MetS. In a randomized, single-blind, placebo-controlled, parallel-arm pilot clinical trial, 19 men and women 20 to 60 years of age with MetS consumed 240 mL of tart cherry juice (Tart Cherry; n = 5 males, 4 females) or an isocaloric placebo-control drink (Control; n = 5 males, 5 females) twice daily for 12 weeks. Arterial stiffness (pulse wave velocity), brachial and aortic blood pressures, wave reflection (augmentation index), and blood biomarkers of cardiovascular and metabolic health were assessed at baseline and 6 and 12 weeks. Oxidized low-density lipoprotein and soluble vascular cell adhesion molecule-1 were significantly lower (P = .047 and P = .036, respectively) in Tart Cherry than Control at 12 weeks, but were not significantly lower than baseline values. There was a trend for total cholesterol to be lower (P = .08) in Tart Cherry than Control at 12 weeks. No significant changes were observed in hemodynamics, arterial stiffness, or other blood biomarkers assessed. These results suggest that daily tart cherry consumption may attenuate processes involved in accelerated atherogenesis without affecting hemodynamics or arterial stiffness parameters in this population. The pilot nature of this study warrants interpreting these findings with caution, and future clinical trials with a larger sample size are needed to confirm these findings.


Asunto(s)
Biomarcadores/sangre , Jugos de Frutas y Vegetales , Síndrome Metabólico/dietoterapia , Prunus/química , Adulto , Células Endoteliales , Femenino , Humanos , Masculino , Síndrome Metabólico/sangre , Persona de Mediana Edad , Proyectos Piloto , Análisis de la Onda del Pulso , Método Simple Ciego , Adulto Joven
3.
Sports (Basel) ; 7(6)2019 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-31242635

RESUMEN

The effects of a multi-ingredient performance supplement (MIPS) incorporating a mixture of branched chain amino acids, beta-alanine, glutamine, creatine, and piperine on resistance training (RT)-induced adaptations remains unclear. Therefore, the purpose of this study was to investigate the effects of this investigational MIPS during six weeks of RT on performance and body composition. Thirty recreationally trained males and females were recruited for this pair-matched, double-blind, placebo-controlled investigation. Subjects were assigned to consume either an experimental MIPS (MIPS) (n = 15) or a placebo (PLA) (n = 15) concurrently with a six-week periodized RT program. Body composition, one-repetition maximum (1RM), and muscular power were assessed at pre- and post-training. Weekly relative volume load was compared between groups. The MIPS and PLA groups demonstrated a significant increase in total body mass (MIPS = +2.9 ± 1.3%; PLA = +2.5 ± 1.7%) and lean mass (MIPS = +5.0 ± 2.1%; PLA = +3.1 ± 1.9%) (p < 0.001) with no changes in fat mass. There were no group × time interactions for any of the body composition measures. Both groups demonstrated similar improvements in maximum strength for the back squat, bench press, and deadlift as well as lower body power from pre- to post-training (p < 0.001). Within the limitations of the current investigation, results failed to demonstrate the benefits of the experimental MIPS for muscular strength and body composition across six weeks of RT compared to PLA.

4.
Int J Sports Physiol Perform ; 14(8): 1081-1088, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31172828

RESUMEN

CONTEXT: Of the 3 branched-chain amino acids (BCAA), leucine has arguably received the most attribution for the role of BCAA supplementation in alleviating symptoms of exercise-induced muscle damage and facilitation of acute performance recovery. PURPOSE: To examine whether enrichment of a standard BCAA supplement with additional leucine or a standalone leucine (LEU) supplement differentially affects exercise-induced muscle damage and performance recovery compared with a standard BCAA supplement. METHODS: A total of 22 recreationally active male and female subjects were recruited and assigned to consume a BCAA, leucine-enriched BCAA (LBCAA), or LEU supplement for 11 d. On the eighth day, subjects performed eccentric-based resistance exercise (ECRE). Lower-body mean average and peak power, plasma creatine kinase, soreness, and pain threshold were measured before and 24, 48, and 72 h after ECRE. RESULTS: LEU showed decreased mean average power (P = .02) and mean peak power (P = .01) from baseline to 48 h post-ECRE, whereas LBCAA and BCAA only trended toward a reduction at 24 hours post-ECRE. At 48 h post-ECRE, BCAA showed greater recovery of mean peak power than LEU (P = .04). At 24 h post-ECRE, LEU demonstrated a greater increase in plasma creatine kinase from baseline than BCAA (P = .04). Area under the curve for creatine kinase was greater in LEU than BCAA (P = .02), whereas BCAA and LBCAA did not differ. Only LEU demonstrated increased soreness during rest and under muscular tension at 24 and 48 h post-ECRE (P < .05). CONCLUSIONS: LBCAA failed to afford any advantages over a standard BCAA supplement for postexercise muscle recovery, whereas a LEU supplement was comparatively ineffective.


Asunto(s)
Aminoácidos de Cadena Ramificada/administración & dosificación , Suplementos Dietéticos , Leucina/administración & dosificación , Mialgia , Entrenamiento de Fuerza , Fenómenos Fisiológicos en la Nutrición Deportiva , Adulto , Creatina Quinasa/sangre , Método Doble Ciego , Femenino , Humanos , Masculino , Músculo Esquelético/fisiología , Descanso , Adulto Joven
5.
Food Funct ; 10(2): 1062-1072, 2019 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-30720034

RESUMEN

Previous research suggests potential for fresh pears as a functional food for promoting cardiometabolic health. The purpose of this randomized, open-label, placebo-controlled, crossover clinical trial was to evaluate the influence of daily fresh pear consumption on blood pressure (primary outcome) and other biomarkers of cardiometabolic health in middle-aged/older adults with metabolic syndrome (MetS). Forty men and women aged 45-65 years with MetS were included and randomly assigned to receive either two medium-sized fresh pears (Pear) or a calorie-matched control drink (Control) per day for each 12-week treatment period, each separated by a 4-week washout period. After 12 weeks of daily fresh pear consumption, systolic blood pressure tended to be reduced (130 ± 2 mmHg vs. 134 ± 2 mmHg at baseline, P = 0.07) and pulse pressure was significantly reduced (51 ± 1 vs. 54 ± 1 at baseline, P < 0.05). At 12 weeks, leptin concentrations were lower in the Pear group than Control (52.5 [7.6, 120.5] ng dL-1vs. 53.4 [5.0, 120.5] ng dL-1, respectively, P < 0.05), and there was a significant group by time interaction (P < 0.05). Leptin concentrations were significantly reduced at 12 weeks compared to baseline in the Pear group (52.5 [7.6, 120.5] ng dL-1vs. 54.8 [6.4, 120.5] ng dL-1 at baseline, P < 0.05) but not in the Control group. Waist circumference was significantly reduced at 12 weeks in the Pear group (107.7 ± 2.0 cm vs. 108.4 ± 2 cm at baseline, P < 0.05) with a trend for a group by time interaction (P < 0.1), and significantly lower in the Pear group than Control (108.1 ± 2.0 cm vs. 108.8 ± 2 cm, P < 0.05) at 6 weeks with a significant group by time interaction (P < 0.05). Conversely, values were significantly increased at 6 weeks (108.8 ± 2 cm vs. 108.3 ± 2.0 cm at baseline, P < 0.05) in the Control group and sustained at 12 weeks. Waist-to-hip ratio was significantly reduced (0.92 ± 0.01 vs. 0.93 ± 0.01 at baseline, P < 0.05) at 12 weeks in the Pear group, and significantly lower than Control at 6 weeks (0.93 ± 0.01 vs. 0.93 ± 0.01, respectively, P < 0.05) and 12 weeks (0.92 ± 0.01 vs. 0.93 ± 0.01, P < 0.05). These findings suggest that daily fresh pear consumption may promote modest improvements in cardiometabolic health in middle-aged/older adults with MetS. This trial was registered at clinicaltrials.gov as NCT02228837.


Asunto(s)
Dieta , Frutas , Síndrome Metabólico/dietoterapia , Pyrus , Anciano , Biomarcadores , Composición Corporal , Metabolismo Energético , Ejercicio Físico , Femenino , Humanos , Masculino , Persona de Mediana Edad
6.
Clin Nutr ; 38(1): 372-382, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29352654

RESUMEN

BACKGROUND: This investigation evaluated the efficacy by which resistance training enhances body composition, metabolic, and functional outcomes for obese patients undergoing a 12-week medically supervised hypocaloric treatment. METHODS: This was a single-blind, randomized, parallel-group prospective trial. Morbidly obese patients were prescribed a 12-week proprietary very low calorie diet (VLCD) treatment (Optifast®) with supplemental protein (1120 kcals/day) and were placed in one of two groups for 14 weeks: 1) Standard Treatment Control (CON) (n = 5) or 2) Resistance Training (RT) (n = 6). Both groups underwent a pedometer-based walking program; however only RT performed resistance training 3 days/week for 12 weeks. Body composition, resting energy expenditure (REE), neuromuscular function, and serum biomarkers were measured at weeks 0, 6, and 13. RESULTS: Both groups exhibited a significant loss of total body mass (TBM) (CON: -19.4 ± 2.3 kg, p = 0.0009 vs. RT: -15.8 ± 1.5 kg, p = 0.0002) and fat mass (FM) (CON: -14.7 ± 1.8 kg, p = 0.0002 vs. RT: -15.1 ± 2.1 kg, p = 0.0002) with no group differences. CON lost 4.6 ± 0.8 kg (p = 0.004) of lean mass (LM) while RT demonstrated no changes. Group differences were found for the relative proportion of total weight-loss due to FM-loss (CON: 75.6 ± 3.4% vs. RT: 96.0 ± 6.0%, p = 0.03) and LM-loss (CON: 24.4 ± 3.2% vs. RT: 4.0 ± 6.5%, p = 0.03). CON demonstrated a 328.6 ± 72.7 kcal/day (-14.3 ± 2.4%) (p = 0.02) decrease in REE while RT exhibited a non-significant decrease of 4.6 ± 1.6% (p = 0.78). RT demonstrated greater improvements in all measures of contractile function and strength when compared to CON (p < 0.05). At post-treatment, RT exhibited greater serum free fatty acids (p = 0.01), glycerol (p = 0.003), and ß-hydroxybutyrate (p = 0.005) than CON. CONCLUSION: Resistance training was advantageous for weight-loss composition by preservation of LM without compromising overall weight- or fat-loss in morbidly obese men and women undergoing a protein supplemented VLCD. These changes accompanied positive adaptations for resting metabolism and muscular function.


Asunto(s)
Dieta Reductora/métodos , Proteínas en la Dieta/administración & dosificación , Suplementos Dietéticos , Obesidad Mórbida/terapia , Entrenamiento de Fuerza/métodos , Pérdida de Peso , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Método Simple Ciego , Terapéutica
7.
Healthcare (Basel) ; 6(3)2018 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-29973574

RESUMEN

Patients with knee osteoarthritis (OA) suffer from immobility and pain. The objective of this cross-sectional study was to investigate the relationship between pain and functionality in middle-aged and older overweight and obese individuals with mild-to-moderate knee OA. Overall pattern, physical activity, and total energy expenditure (TEE) were assessed in 83 participants. The Western Ontario McMaster Universities Arthritis Index (WOMAC) was used to assess lower extremity pain and function. The six-minute walk test (6-MWT) and range of motion (ROM) were also assessed. Results indicated that age was inversely associated with body mass index (BMI) (r = 0.349) and total WOMAC scores (r = 0.247). BMI was positively associated with TEE (r = 0.430) and WOMAC scores (r = 0.268), while ROM was positively associated with the 6-MWT (r = 0.561) and negatively associated with WOMAC (r = 0.338) and pain scores (r = 0.222). Furthermore, women had significantly greater WOMAC scores (p = 0.046) than men. Older participants (≥65 years old) had significantly lower BMI (p = 0.002), and distance traveled during the 6-MWT (p = 0.013). Our findings indicate that older individuals in this population with knee OA had lower BMI, greater ROM, and less pain and stiffness and walked slower than middle-aged individuals. Women reported greater pain, stiffness, and reduced functionality, indicating that the manifestation of OA may vary due to gender.

8.
J Physiol ; 596(10): 1903-1917, 2018 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-29623692

RESUMEN

KEY POINTS: In aged rats, daily muscle stretching increases blood flow to skeletal muscle during exercise. Daily muscle stretching enhanced endothelium-dependent vasodilatation of skeletal muscle resistance arterioles of aged rats. Angiogenic markers and capillarity increased in response to daily stretching in muscles of aged rats. Muscle stretching performed with a splint could provide a feasible means of improving muscle blood flow and function in elderly patients who cannot perform regular aerobic exercise. ABSTRACT: Mechanical stretch stimuli alter the morphology and function of cultured endothelial cells; however, little is known about the effects of daily muscle stretching on adaptations of endothelial function and muscle blood flow. The present study aimed to determine the effects of daily muscle stretching on endothelium-dependent vasodilatation and muscle blood flow in aged rats. The lower hindlimb muscles of aged Fischer rats were passively stretched by placing an ankle dorsiflexion splint for 30 min day-1 , 5 days week-1 , for 4 weeks. Blood flow to the stretched limb and the non-stretched contralateral limb was determined at rest and during treadmill exercise. Endothelium-dependent/independent vasodilatation was evaluated in soleus muscle arterioles. Levels of hypoxia-induced factor-1α, vascular endothelial growth factor A and neuronal nitric oxide synthase were determined in soleus muscle fibres. Levels of endothelial nitric oxide synthase and superoxide dismutase were determined in soleus muscle arterioles, and microvascular volume and capillarity were evaluated by microcomputed tomography and lectin staining, respectively. During exercise, blood flow to plantar flexor muscles was significantly higher in the stretched limb. Endothelium-dependent vasodilatation was enhanced in arterioles from the soleus muscle from the stretched limb. Microvascular volume, number of capillaries per muscle fibre, and levels of hypoxia-induced factor-1α, vascular endothelial growth factor and endothelial nitric oxide synthase were significantly higher in the stretched limb. These results indicate that daily passive stretching of muscle enhances endothelium-dependent vasodilatation and induces angiogenesis. These microvascular adaptations may contribute to increased muscle blood flow during exercise in muscles that have undergone daily passive stretch.


Asunto(s)
Envejecimiento , Volumen Sanguíneo , Endotelio Vascular/fisiología , Hemodinámica , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/fisiología , Condicionamiento Físico Animal , Animales , Acción Capilar , Endotelio Vascular/citología , Masculino , Ejercicios de Estiramiento Muscular , Ratas , Ratas Endogámicas F344
9.
Food Funct ; 8(11): 4139-4149, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29099521

RESUMEN

Growing evidence indicates that strawberries are cardioprotective. We conducted an eight-week randomized, double-blind, placebo-controlled, parallel arm clinical trial to investigate the effects of daily consumption of freeze-dried strawberry powder (FDSP) on blood pressure (BP) and arterial stiffness in pre- and stage 1-hypertensive postmenopausal women. Sixty postmenopausal women were randomly assigned to one of three groups: (1) control, (2) 25 g FDSP and (3) 50 g FDSP (n = 20 per group). Assessments of body weight, BP, arterial stiffness as measured by pulse wave velocity (PWV), and collection of blood samples for analyses of vasoactive and antioxidant molecules were performed at baseline, four and eight weeks. After eight weeks, systolic BP, as well as brachial- and femoral-ankle PWV were lower than baseline in the 25 g FDSP group (141 ± 3 to 135 ± 3 mmHg, P = 0.02; 15.5 ± 0.5 to 14.8 ± 0.4 m s-1, P = 0.03, and 11.0 ± 0.2 to 10.4 ± 0.2 m s-1, P = 0.02, respectively), whereas no statistically significant changes were observed in the control or 50 g FDSP groups. Plasma nitric oxide metabolite levels increased at four and eight weeks in the 50 g FDSP group compared to baseline (8.5 ± 1.2 to 13.6 ± 1.3 and 13.3 ± 1.5, respectively, P = 0.01), whereas no significant changes were observed in the control or 25 g FDSP groups. Serum levels of superoxide dismutase increased at four weeks returning to baseline levels at eight weeks in all three groups. Significant differences among groups were not detected for any of the parameters. Although BP and arterial stiffness improved in the 25 g FDSP group over time, a treatment effect was not observed. Thus, it would be premature to affirm that daily consumption of FDSP improves BP or vascular function in pre- and stage 1-hypertensive postmenopausal women. This trial was registered at as NCT02099578.


Asunto(s)
Presión Sanguínea , Fragaria/metabolismo , Hipertensión/dietoterapia , Posmenopausia/metabolismo , Rigidez Vascular , Anciano , Método Doble Ciego , Femenino , Fragaria/química , Frutas/química , Frutas/metabolismo , Humanos , Hipertensión/metabolismo , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad
10.
Food Funct ; 8(1): 372-380, 2017 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-28059417

RESUMEN

Oxidative stress and inflammation are central to the development of a number of chronic diseases including cardiovascular disease and previous research suggests that blueberry consumption may attenuate these processes. The present study investigated the effects of blueberries on blood biomarkers of oxidative stress, inflammation, and antioxidant defense in postmenopausal women with pre- and stage 1-hypertension. In a randomized, parallel-arm, double-blind, placebo-controlled clinical trial, 40 pre- and stage 1-hypertensive postmenopausal women aged 45 to 65 years were randomly assigned to receive 22 g freeze-dried highbush blueberry powder per day (Blueberry) or 22 g placebo powder per day (Control) for 8 weeks. A blood biomarker of oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine (8-OHdG), as well as blood biomarkers of oxidative stress, inflammation, and antioxidant defense were assessed at baseline, 4 and 8 weeks. 8-OHdG levels were significantly (P = 0.008) lower in Blueberry compared to Control at 4 weeks with a significant time-by-treatment interaction (P = 0.04). Levels were not different between groups at 8 weeks. Other biomarkers measured were not affected by blueberry consumption. Daily consumption of blueberries for 4 weeks, but not 8 weeks, attenuated a biomarker of oxidative DNA damage in pre- and stage 1-hypertensive postmenopausal women. Future clinical studies should directly evaluate the effects of blueberry consumption on oxidative stress, inflammation, and antioxidant defense at the cellular level and in the vasculature in this population.


Asunto(s)
Antioxidantes/metabolismo , Arándanos Azules (Planta)/metabolismo , Hipertensión/dietoterapia , Estrés Oxidativo , Posmenopausia/metabolismo , Anciano , Biomarcadores/sangre , Daño del ADN , Método Doble Ciego , Femenino , Frutas/metabolismo , Humanos , Hipertensión/sangre , Hipertensión/genética , Hipertensión/inmunología , Persona de Mediana Edad , Posmenopausia/inmunología
11.
Appl. cancer res ; 37: 1-10, 2017. ilus
Artículo en Inglés | LILACS, Inca | ID: biblio-915427

RESUMEN

Background: Cancer cachexia is a debilitating paraneoplastic syndrome featuring unintended weight loss and skeletal muscle atrophy. Evidence suggests that bone health may also be compromised, further limiting mobility and quality of life. Aerobic and resistance training was recently reported to differentially affect skeletal muscle adaptations in cancer cachectic mice. The purpose of this investigation was to assess the effects of aerobic and resistance training on bone mineral density (BMD) and bone mineral content (BMC) in mice with colon-26 (C26) tumor-induced cachexia. Methods: Twelve-month old Balb/c mice were aerobic-trained (wheel running 5 days/week) or resistance-trained (weighted ladder climbing 3days/week) for 8 weeks prior to C26 cell injection, followed by an additional three weeks of exercise. BMD and BMC were assessed pre- and post-training by dual-energy x-ray absorptiometry. Results: Resistance-trained C26 mice lost total BMD by 7% (p = 0.06), which did not occur in aerobic-trained C26 mice. In terms of pelvic bone, both resistance- and aerobic-trained C26 mice had significantly lower BMD values (−12%, p = 0.01 and −6%, p = 0.04, respectively), albeit to a lesser degree in aerobic-trained C26 mice. Furthermore, resistance-trained C26 mice tended to lose total BMC (−12%), whereas aerobic-trained C26 mice maintained total BMC. In mice without C26 tumors, resistance training significantly increased total BMD (+13%, p = 0.001). Conclusions: Aerobic and resistance training may differentially affect bone status in C26 cancer cachexia, with high resistance loading possibly being detrimental to total and pelvis BMD, a region expected to bear significant loading stress and contribute substantially to overall mobility. Because resistance training improved BMD in tumor-free mice, the C26 tumor burden appeared to impair the beneficial effect of resistance training on bone mass (AU)


Asunto(s)
Animales , Composición Corporal , Caquexia , Ejercicio Físico , Absorciometría de Fotón , Ratones , Neoplasias , Apoyo Nutricional
12.
Clin Exp Pharmacol Physiol ; 43(12): 1243-1246, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27558210

RESUMEN

Sarcopenia, defined by reduced appendicular skeletal muscle mass (ASM)/height2 (ASMI), is associated with increased arterial stiffness (brachial-ankle pulse wave velocity, baPWV) and wave reflection (augmentation index, AIx). Blood pressure (BP) responses to metaboreflex activation (post-exercise muscle ischemia, PEMI) are exaggerated in older prehypertensives and hypertensives. We examined peripheral and aortic haemodynamics at rest and during PEMI in postmenopausal women with low-ASMI and normal-ASMI. Resting radial AIx and baPWV as well as brachial and aortic systolic BP, pulse pressure, systolic time index, and subendocardial viability ratio (SEVR) responses to PEMI were greater in women with low-ASMI than normal-ASMI. Increased baPWV associated with low-ASMI may play a major role in the exaggerated pulse pressure and SEVR responses to PEMI in postmenopausal women.


Asunto(s)
Presión Sanguínea/fisiología , Músculo Esquelético/metabolismo , Posmenopausia/metabolismo , Análisis de la Onda del Pulso , Índice Tobillo Braquial/métodos , Femenino , Humanos , Persona de Mediana Edad , Análisis de la Onda del Pulso/métodos , Sarcopenia/diagnóstico , Sarcopenia/metabolismo , Rigidez Vascular/fisiología
13.
Metabolism ; 65(5): 685-698, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27085776

RESUMEN

PURPOSE: The appropriate mode of exercise training for cancer cachexia is not well-established. Using the colon-26 (C26) mouse model of cancer cachexia, we defined and compared the skeletal muscle responses to aerobic and resistance training. METHODS: Twelve-month old Balb/c mice were initially assigned to control, aerobic training (AT; wheel running), or resistance training (RT; ladder climbing) (n=16-17/group). After 8weeks of training, half of each group was injected with C26 tumor cells, followed by 3 additional weeks of training. Body composition and neuromuscular function was evaluated pre- and post-training. Muscles were collected post-training and analyzed for fiber cross-sectional area (CSA), Akt-mTOR signaling, and expression of insulin-like growth factor-I (IGF-I) and myogenic regulatory factors. RESULTS: Total body mass decreased (p<0.05) in C26 (-8%), AT+C26 (-18%), and RT+C26 (-15%) but not control. Sensorimotor function declined (p<0.05) in control (-16%), C26 (-13%), and RT+C26 (-23%) but not AT+C26. Similarly, strength/body weight decreased (p<0.05) in control (-7%), C26 (-21%), and RT+C26 (-10%) but not AT+C26. Gastrocnemius mass/body weight tended to be greater in AT+C26 vs. C26 (+6%, p=0.09). Enlargement of the spleen was partially corrected in AT+C26 (-27% vs. C26, p<0.05). Fiber CSA was lower in all C26 groups vs. control (-32% to 46%, p<0.05); however, the effect size calculated from C26 and AT+C26 was large (+24%, d=1.04). Phosphorylated levels of mTOR in AT+C26 exceeded C26 (+32%, p<0.05). RT+C26 showed greater mRNA expression (p<0.05) of IGF-IEa (+79%) and myogenin (+126%) with a strong tendency for greater IGF-IEb (+127%, p=0.069) vs. CONCLUSIONS: Aerobic or resistance training was unable to prevent tumor-induced body weight loss. However, aerobic training may have preserved function, reduced the inflammatory response of the spleen, and marginally rescued muscle mass possibly through activation of mTOR. Aerobic training may therefore have therapeutic value for patients with cancer cachexia. In contrast, resistance training induced the expression of genes associated with muscle damage and repair. This gene response may be supportive of excessive stress generated by high resistance loading in a tumor-bearing state.


Asunto(s)
Caquexia/prevención & control , Neoplasias del Colon/terapia , Modelos Animales de Enfermedad , Actividad Motora , Desarrollo de Músculos , Músculo Esquelético/patología , Entrenamiento de Fuerza , Animales , Caquexia/etiología , Caquexia/fisiopatología , Línea Celular Tumoral , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Neoplasias del Colon/fisiopatología , Femenino , Regulación Neoplásica de la Expresión Génica , Ratones Endogámicos BALB C , Debilidad Muscular/etiología , Debilidad Muscular/prevención & control , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatología , Trasplante de Neoplasias , Fosforilación , Procesamiento Proteico-Postraduccional , Proteínas Proto-Oncogénicas c-akt/agonistas , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Distribución Aleatoria , Transducción de Señal , Serina-Treonina Quinasas TOR/química , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo
14.
Food Funct ; 7(3): 1628-33, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26923532

RESUMEN

Postmenopausal osteoporosis may be caused, in part, by oxidative stress and inflammation. Vitamin E is a strong antioxidant which has been shown to have anti-inflammatory and bone-protective effects. The objective of this study was to investigate the effects of various doses of supplemental vitamin E on osteoclastogenesis in ovariectomized rats. Sixty 12-month-old female Sprague-Dawley rats were sham-operated (Sham) or ovariectomized (Ovx; 4 groups) and fed a diet containing basal levels of vitamin E (75 mg D-α tocopherol acetate per kg diet) for 220 days. Rats in three of the Ovx groups were given supplemental doses of vitamin E (300, 525, and 750 mg D-α tocopherol acetate per kg diet) for the last 100 days. Femoral bone marrow cells were isolated, cultured, and osteoclasts were counted and normalized to 1000 total bone marrow cells. Blood monocyte and lymphocyte counts were also determined. Osteoclast number was significantly higher in the Ovx control group and was suppressed by all three doses of vitamin E, although more effectively in the Ovx group that received 300 mg per kg diet vitamin E. Additionally, vitamin E suppressed the Ovx-induced increase in monocyte and lymphocyte production. The results of this study suggest that vitamin E supplementation suppresses osteoclastogenesis, possibly by inhibiting monocyte and lymphocyte production.


Asunto(s)
Osteogénesis/efectos de los fármacos , Osteoporosis Posmenopáusica/tratamiento farmacológico , Vitamina E/administración & dosificación , Animales , Densidad Ósea/efectos de los fármacos , Células Cultivadas , Suplementos Dietéticos/análisis , Femenino , Fémur/efectos de los fármacos , Fémur/fisiopatología , Humanos , Osteoclastos/citología , Osteoclastos/efectos de los fármacos , Osteoporosis Posmenopáusica/fisiopatología , Ovariectomía , Ratas , Ratas Sprague-Dawley
15.
Exp Gerontol ; 70: 119-24, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26192974

RESUMEN

Wave reflection (augmentation pressure [AP] and index [AIx]) is greater in older women than men. Resting AP is a better wave reflection index than AIx in older adults. The negative relationship between wave reflection and lean mass (LM) has been inconsistent. We investigated the impact of age and LM on aortic hemodynamic responses to metaboreflex activation in post-menopausal women. Post-menopausal women, younger and older (n=20 per group) than 60 years, performed 2-min isometric handgrip at 30% of maximal force followed by 3-min post-exercise muscle ischemia (PEMI). We measured carotid-femoral pulse wave velocity (cfPWV) and femoral-ankle PWV (faPWV) at rest, and aortic systolic blood pressure (aSBP), pulse pressure (aPP), AP, AIx, and AIx-adjusted for heart rate (AIx@75) at rest and during PEMI using tonometry. Arm and leg LM were measured by DEXA. Resting cfPWV, aSBP, and aPP were higher, while AIx@75 and leg LM were lower in older than younger women. aSBP and aPP increased similarly during PEMI in both groups. Increases in AP (P<0.05), AIx (P<0.05), and AIx@75 (P<0.01) during PEMI were greater in older than younger women. From these responses, only AP during PEMI was correlated (P<0.05) positively with aSBP and aPP responses, and negatively with leg LM. Resting faPWV, but not cfPWV, was correlated (P<0.01) with AP, aSBP, and aPP during PEMI. Therefore, PEMI induces greater wave reflection responses in older than younger post-menopausal women. Our findings suggest that the increased AP response to PEMI is related to leg arterial stiffness and muscle loss in older women.


Asunto(s)
Envejecimiento/fisiología , Aorta/fisiología , Músculo Esquelético/metabolismo , Posmenopausia/fisiología , Anciano , Envejecimiento/patología , Presión Sanguínea/fisiología , Composición Corporal/fisiología , Arteria Braquial/fisiología , Ejercicio Físico/fisiología , Femenino , Hemodinámica/fisiología , Humanos , Pierna/patología , Persona de Mediana Edad , Músculo Esquelético/patología , Análisis de la Onda del Pulso , Reflejo/fisiología , Sarcopenia/patología , Sarcopenia/fisiopatología , Rigidez Vascular/fisiología
16.
J Acad Nutr Diet ; 115(3): 369-377, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25578927

RESUMEN

BACKGROUND: Postmenopausal women have a high prevalence of hypertension and often develop arterial stiffness thereby increasing cardiovascular disease risk. Although antihypertensive drug therapies exist, increasing numbers of people prefer natural therapies. In vivo studies and a limited number of clinical studies have demonstrated the antihypertensive and vascular-protective effects of blueberries. OBJECTIVE: To examine the effects of daily blueberry consumption for 8 weeks on blood pressure and arterial stiffness in postmenopausal women with pre- and stage 1-hypertension. DESIGN: This was an 8-week, randomized, double-blind, placebo-controlled clinical trial. PARTICIPANTS/SETTING: Forty-eight postmenopausal women with pre- and stage 1-hypertension recruited from the greater Tallahassee, FL, area participated. INTERVENTION: Participants were randomly assigned to receive either 22 g freeze-dried blueberry powder or 22 g control powder. MAIN OUTCOME MEASURES: Resting brachial systolic and diastolic blood pressures were evaluated and arterial stiffness was assessed using carotid-femoral pulse wave velocity and brachial-ankle pulse wave velocity. C-reactive protein, nitric oxide, and superoxide dismutase were measured at baseline, 4 weeks, and 8 weeks. STATISTICAL ANALYSES PERFORMED: Statistical analysis was performed using a split plot model of repeated measures analysis of variance. RESULTS: After 8 weeks, systolic blood pressure and diastolic blood pressure (131±17 mm Hg [P<0.05] and 75±9 mm Hg [P<0.01], respectively) and brachial-ankle pulse wave velocity (1,401±122 cm/second; P<0.01) were significantly lower than baseline levels (138±14 mm Hg, 80±7 mm Hg, and 1,498±179 cm/second, respectively), with significant (P<0.05) group×time interactions in the blueberry powder group, whereas there were no changes in the group receiving the control powder. Nitric oxide levels were greater (15.35±11.16 µmol/L; P<0.01) in the blueberry powder group at 8 weeks compared with baseline values (9.11±7.95 µmol/L), whereas there were no changes in the control group. CONCLUSIONS: Daily blueberry consumption may reduce blood pressure and arterial stiffness, which may be due, in part, to increased nitric oxide production.


Asunto(s)
Arándanos Azules (Planta) , Frutas , Hipertensión/dietoterapia , Anciano , Índice Tobillo Braquial , Presión Sanguínea/fisiología , Proteína C-Reactiva/metabolismo , Método Doble Ciego , Femenino , Florida , Humanos , Hipertensión/sangre , Hipertensión/fisiopatología , Persona de Mediana Edad , Óxido Nítrico/sangre , Análisis de la Onda del Pulso , Superóxido Dismutasa/sangre , Rigidez Vascular/fisiología
17.
J Med Food ; 18(3): 324-31, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25314004

RESUMEN

Menopause leads to an increased risk for osteoporosis in women. Although drug therapies exist, increasing numbers of people prefer alternative therapies such as dietary supplements, for example, calcium, vitamin D, and collagen hydrolysates for the prevention and treatment of osteoporosis. We have previously shown that a 3-month intervention using a calcium-collagen chelate (CC) dietary supplement was efficacious in improving bone mineral density (BMD) and blood biomarkers of bone turnover in osteopenic postmenopausal women. This study reports the long-term efficacy of CC in reducing bone loss in postmenopausal women with osteopenia. Thirty-nine women were randomly assigned to one of two groups: 5 g of CC containing 500 mg of elemental calcium and 200 IU vitamin D (1,25-dihydroxyvitamin D3) or control (500 mg of calcium and 200 IU vitamin D) daily for 12 months. Total body, lumbar, and hip BMD were evaluated at baseline, 6 and 12 months using dual-energy X-ray absorptiometry. Blood was collected at baseline, 6 and 12 months to assess levels of blood biomarkers of bone turnover. Intent-to-treat (ITT) analysis was performed using repeated measures analysis of variance pairwise comparisons and multivariate analysis to assess time and group interactions. The loss of whole body BMD in women taking CC was substantially lower than that of the control group at 12 months in those who completed the study and the ITT analysis, respectively (CC: -1.33% and -0.33% vs. control: -3.75% and -2.17%; P=.026, P=.035). The CC group had significantly reduced levels of sclerostin and tartrate-resistant acid phosphatase isoform 5b (TRAP5b) (P<.05), and higher bone-specific alkaline phosphatase/TRAP5b ratio (P<.05) than control at 6 months. These results support the use of CC in reducing bone loss in osteopenic postmenopausal women.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Enfermedades Óseas Metabólicas/tratamiento farmacológico , Huesos/efectos de los fármacos , Calcio/uso terapéutico , Colágeno/orina , Suplementos Dietéticos , Osteoporosis Posmenopáusica/prevención & control , Fosfatasa Ácida/sangre , Proteínas Adaptadoras Transductoras de Señales , Fosfatasa Alcalina/sangre , Biomarcadores/sangre , Enfermedades Óseas Metabólicas/metabolismo , Proteínas Morfogenéticas Óseas/sangre , Huesos/metabolismo , Calcio/farmacología , Colágeno/farmacología , Femenino , Marcadores Genéticos , Humanos , Análisis de Intención de Tratar , Persona de Mediana Edad , Osteoporosis Posmenopáusica/metabolismo , Posmenopausia
18.
J Obes ; 2014: 690123, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25309751

RESUMEN

Obesity and osteoporosis are two chronic conditions that have been increasing in prevalence. Despite prior data supporting the positive relationship between body weight and bone mineral density (BMD), recent findings show excess body weight to be detrimental to bone mass, strength, and quality. To evaluate whether obesity would further exacerbate the effects of ovariectomy on bone, we examined the tibiae and fourth lumbar (L4) vertebrae from leptin receptor-deficient female (Lepr(fa/fa)) Zucker rats and their heterozygous lean controls (Lepr(fa/+)) that were either sham-operated or ovariectomized (Ovx). BMD of L4 vertebra was measured using dual-energy X-ray absorptiometry, and microcomputed tomography was used to assess the microstructural properties of the tibiae. Ovariectomy significantly (P < 0.001) decreased the BMD of L4 vertebrae in lean and obese Zucker rats. Lower trabecular number and greater trabecular separation (P < 0.001) were also observed in the tibiae of lean- and obese-Ovx rats when compared to sham rats. However, only the obese-Ovx rats had lower trabecular thickness (Tb.Th) (P < 0.005) than the other groups. These findings demonstrated that ovarian hormone deficiency adversely affected bone mass and quality in lean and obese rats while obesity only affected Tb.Th in Ovx-female Zucker rats.


Asunto(s)
Vértebras Lumbares/patología , Obesidad/patología , Osteocitos/metabolismo , Osteoporosis/patología , Ovariectomía/efectos adversos , Receptores de Leptina/deficiencia , Tibia/patología , Absorciometría de Fotón , Animales , Densidad Ósea , Femenino , Ratas , Ratas Zucker
19.
J Int Soc Sports Nutr ; 11: 37, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25093015

RESUMEN

BACKGROUND: The present study investigated the effects of a multi-ingredient dietary supplement (MIDS) containing caffeine, conjugated linoleic acid (CLA), green tea, and branched-chain amino acids (BCAA) taken for 8 weeks on body composition, blood lipid profile, glucose, insulin, adiponectin, leptin, and high-sensitivity C-reactive protein (hs-CRP) in overweight and obese men and women. METHODS: Twenty-two participants completed the study (PL, n = 11; 7 women, 4 men; age, 34 ± 3.5 years; height, 169.2 ± 3.3 cm; body mass, 96.9 ± 6.8 kg; BMI, 34.1 ± 1.8 kg/m(2); MIDS, n = 11; 9 women, 2 men; age, 36 ± 3.4 years; height, 173.2 ± 2.9 cm; body mass, 91.9 ± 5.6 kg; BMI, 30.0 ± 1.5 kg/m(2)). Participants were randomly assigned and stratified by body fat percentage to two groups: 1) a soybean oil placebo (PL) or 2) MIDS. Each group consumed two pills with breakfast and two pills with lunch. Body composition and android fat, waist and hip circumferences, blood pressure and heart rate were measured at baseline and after 8 weeks of supplementation. RESULTS: There were no significant changes for any of the variables of body composition. Feelings of hunger were significantly higher in MIDS versus PL with no changes observed in satiety or desire to eat. Heart rate and blood pressure were unaltered in MIDS after 8 weeks of supplementation. Furthermore, lipid profile, food intake, mood state variables, fasting blood glucose, and endocrine markers did not significantly change regardless of group. CONCLUSION: MIDS intake does not appear to alter body composition or markers of cardiovascular health versus PL. Moreover, MIDS may actually increase feelings of hunger versus PL.

20.
Food Sci Nutr ; 2(2): 174-80, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24804076

RESUMEN

The effects of guava leaves extracted using solvents of water, ethanol, methanol, and different concentrations of hydroethanolic solvents on phenolic compounds and flavonoids, and antioxidant properties have been investigated. The antioxidant capability was assessed based on 2,2-diphenyl-1-picrylhydrazyl radical and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical-scavenging abilities, reducing power, and nitric oxide-and nitrate-scavenging activities. The results demonstrated that the antioxidant ability of guava leaf extracts has a strong relationship with phenolic compound content rather than flavonoid content. Phenolic compound content of water extracted guava leaves was higher compared to pure ethanol and methanol extracts. However, phenolic compound content extracted using hydroethanolic solvent was higher than water, whereas 50% hydroethanolic was observed to be the most effective solvent showing high antioxidant ability.

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