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1.
Nutrients ; 14(19)2022 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-36235628

RESUMEN

This research examined the effects of single-dose molecular hydrogen (H2) supplements on acid-base status and local muscle deoxygenation during rest, high-intensity intermittent training (HIIT) performance, and recovery. Ten healthy, trained subjects in a randomized, double-blind, crossover design received H2-rich calcium powder (HCP) (1500 mg, containing 2.544 µg of H2) or H2-depleted placebo (1500 mg) supplements 1 h pre-exercise. They performed six bouts of 7 s all-out pedaling (HIIT) at 7.5% of body weight separated by 40 s pedaling intervals, followed by a recovery period. Blood gases' pH, PCO2, and HCO3- concentrations were measured at rest. Muscle deoxygenation (deoxy[Hb + Mb]) and tissue O2 saturation (StO2) were determined via time-resolved near-infrared spectroscopy in the vastus lateralis (VL) and rectus femoris (RF) muscles from rest to recovery. At rest, the HCP group had significantly higher PCO2 and HCO3- concentrations and a slight tendency toward acidosis. During exercise, the first HIIT bout's peak power was significantly higher in HCP (839 ± 112 W) vs. Placebo (816 ± 108 W, p = 0.001), and HCP had a notable effect on significantly increased deoxy[Hb + Mb] concentration during HIIT exercise, despite no differences in heart rate response. The HCP group showed significantly greater O2 extraction in VL and microvascular (Hb) volume in RF during HIIT exercise. The HIIT exercise provided significantly improved blood flow and muscle reoxygenation rates in both the RF and VL during passive recovery compared to rest in all groups. The HCP supplement might exert ergogenic effects on high-intensity exercise and prove advantageous for improving anaerobic HIIT exercise performance.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad , Sustancias para Mejorar el Rendimiento , Calcio/metabolismo , Gases/metabolismo , Humanos , Hidrógeno/metabolismo , Músculo Esquelético/metabolismo , Consumo de Oxígeno/fisiología , Sustancias para Mejorar el Rendimiento/metabolismo , Polvos
2.
Nutrients ; 13(2)2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-33573133

RESUMEN

We investigated effects of molecular hydrogen (H2) supplementation on acid-base status, pulmonary gas exchange responses, and local muscle oxygenation during incremental exercise. Eighteen healthy, trained subjects in a randomized, double-blind, crossover design received H2-rich calcium powder (HCP) (1500 mg/day, containing 2.544 µg/day of H2) or H2-depleted placebo (1500 mg/day) for three consecutive days. They performed cycling incremental exercise starting at 20-watt work rate, increasing by 20 watts/2 min until exhaustion. Breath-by-breath pulmonary ventilation (V˙E) and CO2 output (V˙CO2) were measured and muscle deoxygenation (deoxy[Hb + Mb]) was determined via time-resolved near-infrared spectroscopy in the vastus lateralis (VL) and rectus femoris (RF). Blood gases' pH, lactate, and bicarbonate (HCO3-) concentrations were measured at rest and 120-, 200-, and 240-watt work rates. At rest, the HCP group had significantly lower V˙E, V˙CO2, and higher HCO3-, partial pressures of CO2 (PCO2) versus placebo. During exercise, a significant pH decrease and greater HCO3- continued until 240-watt workload in HCP. The V˙E was significantly lower in HCP versus placebo, but HCP did not affect the gas exchange status of V˙CO2 or oxygen uptake (V˙O2). HCP increased absolute values of deoxy[Hb + Mb] at the RF but not VL. Thus, HCP-induced hypoventilation would lead to lower pH and secondarily impaired balance between O2 delivery and utilization in the local RF during exercise, suggesting that HCP supplementation, which increases the at-rest antioxidant potential, affects the lower ventilation and pH status during incremental exercise. HPC induced a significantly lower O2 delivery/utilization ratio in the RF but not the VL, which may be because these regions possess inherently different vascular/metabolic control properties, perhaps related to fiber-type composition.


Asunto(s)
Antioxidantes/uso terapéutico , Ejercicio Físico/fisiología , Hidrógeno/uso terapéutico , Administración Oral , Antioxidantes/administración & dosificación , Bicarbonatos/sangre , Análisis de los Gases de la Sangre , Pruebas Respiratorias , Dióxido de Carbono/análisis , Estudios Cruzados , Método Doble Ciego , Humanos , Hidrógeno/administración & dosificación , Masculino , Músculo Esquelético/química , Oxígeno/análisis , Presión Parcial , Polvos , Espectroscopía Infrarroja Corta , Adulto Joven
3.
J Nutr Biochem ; 19(4): 229-36, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17601722

RESUMEN

OBJECTIVE: The aim of this study was to investigate the cholesterol-lowering mechanisms of corn fiber oil (CFO), ferulate phytostanyl esters (FPEs) and parent compounds of FPE, including sitostanol and ferulic acid, in hamsters. METHOD: Seventy male Golden Syrian hamsters were randomly assigned to six experimental diets for 4 weeks: (1) cornstarch-casein-sucrose-based control diet (control); and (2) control diet plus 0.1% (wt/wt) cholesterol (cholesterol-control). The remaining four groups were given cholesterol-control diet with: (3) 10% (wt/wt) CFO; (4) 0.5% (wt/wt) sitostanol; (5) 0.23% (wt/wt) ferulic acid; and (6) 0.73% (wt/wt) FPE. At the end of dietary intervention, total plasma cholesterol, high-density lipoprotein cholesterol and triglyceride concentrations were determined. Parameters of cholesterol kinetics, including cholesterol absorption and synthesis, as well as mRNA expression of sterol transporters such as Niemann-Pick C1 like 1 (NPC1L1), ATP-binding cassette G5 (ABCG5) and ABCG8, were assessed. RESULTS: Supplementation with CFO decreased (P<.0001) plasma total cholesterol levels by 29% as compared with the cholesterol-control group, while FPE and sitostanol reduced (P<.02) cholesterolemia by 15% and 14%, respectively. CFO and sitostanol decreased (P<.05) cholesterol absorption by 24% compared to the cholesterol-control group. Dietary intervention did not alter the intestinal gene expression of ABCG5, ABCG8 and NPC1L1. CONCLUSION: The present results show that the CFO-induced and sitostanol-induced decrease in cholesterol absorption is independent of intestinal enterocyte sterol transporters such as ABCG5, ABCG8 and NPC1L1 in hamsters.


Asunto(s)
Anticolesterolemiantes/farmacología , Colesterol/metabolismo , Aceite de Maíz/farmacología , Mucosa Intestinal/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Sitoesteroles/farmacología , Esteroles/metabolismo , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Animales , Anticolesterolemiantes/administración & dosificación , Aceite de Maíz/administración & dosificación , Ácidos Cumáricos/farmacología , Cricetinae , Absorción Intestinal , Masculino , Proteínas de Transporte de Membrana/genética , Fitosteroles/farmacología , Sitoesteroles/administración & dosificación
4.
Br J Nutr ; 98(3): 550-5, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17459188

RESUMEN

The hypolipidaemic effects of plant sterols are well established. However, mechanisms by which plant sterols lower plasma cholesterol levels, particularly at the molecular level, have not been clearly elucidated. The objective of the present study was to determine whether different plant sterol analogues reduce plasma cholesterol levels by up regulating the sterol transporters ABCG5 and ABCG8 in the liver and/or small intestine. Male Golden Syrian hamsters were divided into eight groups. Groups 1 and 2 were fed a maize starch-casein-sucrose-based diet that did not contain cholesterol (control; Con) or the Con diet with the addition of 0.25 % cholesterol (Ch-Con). Groups 3-8 were fed the Ch-Con diet supplemented with 1 % plant sterols, 1 % plant stanols, 1 % of a plant sterol and stanol mixture (50:50), 1.76 % plant sterol-fish oil esters, or 0.71 or 1.43 % stanol-ascorbic acid esters, respectively. After 5 weeks, the Ch-Con diet up regulated the ABCG5 mRNA expression and tended (P = 0.083) to increase ABCG8 mRNA expression in the liver, but did not affect both genes' expression in the small intestine compared with the Con diet. Hamsters fed 0.7 % stanol esters showed lower plasma cholesterol levels (P < 0.001) and also lower liver ABCG5 mRNA expression (P < 0.05) compared with the Ch-Con diet. Plant stanols, stanol esters, and sterol esters did not affect the ABCG5 or ABCG8 mRNA expressions in the liver and intestine although they reduced plasma cholesterol levels. These results suggest that plant sterols and their derivatives reduce plasma cholesterol levels independently from the mRNA expression of ABCG5 and ABCG8 transporters.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Hipercolesterolemia/genética , Fitosteroles , Animales , Peso Corporal/genética , Colesterol/sangre , HDL-Colesterol/sangre , Cricetinae , Dieta , Ingestión de Alimentos , Hipercolesterolemia/sangre , Intestino Delgado/química , Hígado/química , Masculino , Mesocricetus , Regulación hacia Arriba/genética
5.
Br J Nutr ; 97(2): 381-8, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17298709

RESUMEN

Policosanols (PC) exist as very-long-chain alcohols derived from sugarcane currently used in many countries as a cholesterol-lowering therapy. PC purity and relative percentage composition have been suggested as primary reasons why the original Cuban PC (OPC) supplements possess lipid-lowering efficacy. The purpose of the present study was, first, to compare the relative percentage purity and PC composition of both OPC and alternative sources of PC (APC). A second objective was to feed Syrian hamsters a diet containing 0.275 mg PC/g of either the OPC or an APC product (APC1) and compare subsequent tissue, plasma and faecal PC levels. Five animals from the APC1 dietary group received a diet containing ten times the original amount of PC. Results indicate that the APC formulations have a composition that is highly consistent with the OPC supplement, with octacosanol being present within the cited 60-70 % range. PC were undetectable in the small intestine, liver, adipose or plasma in animals fed either source. Hamsters fed OPC excreted octacosanol (C28) more rapidly (P < 0.05) than hamsters receiving APC1. If the cholesterol-lowering efficacy of PC mixtures is dependent on their purity and composition, then sugarcane-derived APC products should possess similar therapeutic properties as the OPC supplement.


Asunto(s)
Anticolesterolemiantes/química , Alcoholes Grasos/química , Saccharum/química , Absorción , Animales , Anticolesterolemiantes/administración & dosificación , Anticolesterolemiantes/farmacocinética , Cricetinae , Cuba , Suplementos Dietéticos , Alcoholes Grasos/administración & dosificación , Alcoholes Grasos/farmacocinética , Alcoholes Grasos/orina , Heces/química , Mesocricetus , Distribución Tisular
6.
Atherosclerosis ; 194(1): 153-8, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17123537

RESUMEN

Policosanol is a mixture of higher aliphatic alcohols shown to have beneficial effects on plasma lipid levels in animals and humans. Over 50 studies have reported significant reductions in plasma cholesterol using policosanol obtained from Cuban sugar cane (Dalmer, La Havana, Cuba). However, other research groups using policosanol from alternative sources have failed to reproduce the efficacy of these alcohols observed in earlier studies. Therefore, the objective of the present study was to compare the cholesterol-lowering effect of the Dalmer sugar cane policosanol (SCP) product versus an alternative mixture of similar policosanol composition. Forty-eight male Golden Syrian hamsters were randomly assigned to four groups and fed experimental diets ad libitum for a period of 4 weeks: (i) non-cholesterol control, (ii) 0.1% cholesterol control, (iii) 0.1% cholesterol diet supplemented with 275 mg/kg diet of Dalmer Cuban sugar cane policosanol and (iv) 0.1% cholesterol diet supplemented with 275 mg/kg diet of alternative sugar cane policosanol. Hamsters were sacrificed and blood was collected at the end of the feeding period. Body weights and food intakes were similar across study groups. Neither of the two policosanol treatments had any significant effect on plasma lipid levels, as compared to cholesterol control. The outcome of the present study questions the clinical usefulness of policosanol mixtures as cholesterol-lowering nutraceuticals.


Asunto(s)
Anticolesterolemiantes/farmacología , Colesterol en la Dieta/sangre , Alcoholes Grasos/farmacología , Hipercolesterolemia/tratamiento farmacológico , Saccharum/química , Alimentación Animal , Animales , Peso Corporal/efectos de los fármacos , Colesterol en la Dieta/farmacología , HDL-Colesterol/sangre , Cricetinae , Ingestión de Alimentos/fisiología , Hipercolesterolemia/sangre , Masculino , Mesocricetus , Triglicéridos/sangre
7.
J Nutr ; 136(4): 1012-6, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16549466

RESUMEN

Recommendations for decreasing the risk of developing cardiovascular disease include increasing the intake of plant sterols and fish oil. The cholesterol-lowering action of plant sterols, when provided in a fish-oil fatty acids vehicle, remains to be investigated in humans. A randomized, crossover-feeding, single-blind trial was conducted in 30 subjects with mild-to-moderate hypercholesterolemia to study the effects on plasma lipids of 2 novel forms of plant sterols: those combined with, or esterified to, fish-oil fatty acids. The treatments were margarine (control), free plant sterols, plant sterols esterified to fatty acids from sunflower oil, plant sterols esterified to very long-chained fatty acids from fish oil, and plant sterols combined with the same amount of very long-chained fatty acids from fish oil. Each sterol-containing food (1.0-1.8 g plant sterols/d) was consumed for 29 d as a single dose with breakfast under staff supervision. Compared with the control treatment, none of the plant sterol preparations reduced plasma total cholesterol or LDL cholesterol, triacylglycerol, apolipoprotein A-I, apolipoprotein B, lipoprotein (a), or C-reactive protein concentration. Relative to the control phase, all plant sterols treatment increased the plasma HDL cholesterol concentration (P < 0.05) by approximately 8%. In conclusion, because standard forms of plant sterols did not reduce plasma cholesterol concentrations, the efficacy of the new formulation of plant sterols cannot be confirmed from the present study design, where plant sterols were given as a single morning dose.


Asunto(s)
Dieta , Aceites de Pescado/administración & dosificación , Hipercolesterolemia/tratamiento farmacológico , Lípidos/sangre , Fitosteroles/administración & dosificación , Anciano , Apolipoproteína A-I/sangre , Apolipoproteínas B/sangre , Proteína C-Reactiva/análisis , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Estudios Cruzados , Esterificación , Ácidos Grasos/administración & dosificación , Ácidos Grasos/química , Femenino , Humanos , Hipercolesterolemia/sangre , Lipoproteína(a)/sangre , Masculino , Persona de Mediana Edad , Fitosteroles/química , Aceites de Plantas/química , Aceite de Girasol
8.
Lipids ; 40(2): 175-80, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15884766

RESUMEN

The aim of this study was to assess the efficacy of a novel water-soluble phytostanol analog, disodium ascorbyl phytostanyl phosphates (DAPP), on plasma lipid levels and red blood cell fragility in hamsters fed atherogenic diets. For 5 wk, 50 male Golden Syrian hamsters were fed a semipurified diet without added cholesterol (noncholesterol, group 1), or a semipurified diet with 0.25% cholesterol (cholesterol-control, group 2). Groups 3-5 were fed the cholesterol-control diet with an addition of 1% phytostanols (diet 3), 0.71% DAPP (DAPP 0.7%, diet 4), or 1.43% DAPP (DAPP 1.4%, diet 5). Diets 4 and 5 provided 0.5 and 1% phytostanols, respectively. Supplementation of 0.71 and 1.43% DAPP decreased plasma total cholesterol concentrations by 34 (P < 0.001) and 46% (P< 0.001), respectively, in comparison with the cholesterol-control group, whereas free stanols reduced (P = 0.007) plasma cholesterol concentrations by 14%. Similarly, non-HDL-cholesterol concentrations were reduced by 39 (P < 0.001) and 54% (P < 0.001) in hamsters supplemented with DAPP 0.7% and DAPP 1.4%, respectively, relative to the cholesterol-control group. The hypocholesterolemic effect of DAPP 1.4% was threefold stronger than that of free stanols. In hamsters supplemented with DAPP 1.4%, plasma TG concentrations were 45% lower (P= 0.018) than in cholesterol-control-fed hamsters, whereas no such beneficial effect was observed in the free stanol group. Erythrocyte fragility was unaffected by DAPP or free phytostanols. Results of the current study demonstrate that DAPP lowers cholesterol more efficiently than free stanols, without an adverse effect on erythrocyte fragility in hamsters.


Asunto(s)
Colesterol/sangre , Fitosteroles/uso terapéutico , Sitoesteroles/uso terapéutico , Animales , Peso Corporal , Cricetinae , Masculino , Fragilidad Osmótica/efectos de los fármacos , Solubilidad , Agua/química
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