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1.
Int J Mol Sci ; 20(19)2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31590233

RESUMO

A hollow-type spherical bacterial cellulose (HSBC) gel prepared using conventional methods cannot load particles larger than the pore size of the cellulose nanofiber network of bacterial cellulose (BC) gelatinous membranes. In this study, we prepared a HSBC gel encapsulating target substances larger than the pore size of the BC gelatinous membranes using two encapsulating methods. The first method involved producing the BC gelatinous membrane on the surface of the core that was a spherical alginate gel with a diameter of 2 to 3 mm containing the target substances. With this method, the BC gelatinous membrane was biosynthesized using Gluconacetobacter xylinus at the interface between the cell suspension attached onto the alginate gel and the silicone oil. The second method involved producing the BC gel membrane on the interface between the silicone oil and cell suspension, as well as the spherical alginate gel with a diameter of about 1 mm containing target substances. After the BC gelatinous membrane was biosynthesized, an alginate gel was dissolved in a phosphate buffer to prepare an HSBC gel with the target substances. These encapsulated substances could neither pass through the BC gelatinous membrane of the HSBC gel nor leak from the interior space of the HSBC gel. These results suggest that the HSBC gel had a molecular sieving function. The HSBC gel walls prepared using these methods were observed to be uniform and would be useful for encapsulating bioactive molecules, such as immobilized enzymes in HSBC gel, which is expected to be used as a drug carrier.


Assuntos
Cápsulas/química , Celulose/análogos & derivados , Gluconacetobacter xylinus/química , Microgéis/química , Alginatos/química , Membranas Artificiais , Silicones/química
2.
Gels ; 10(7)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-39057441

RESUMO

To reduce the risk of the adsorption of granular activated carbon in the gastrointestinal tract, we successfully produced a hollow-type spherical bacterial cellulose (HSBC) gel containing activated carbon with a particle size of 6 µm. In this study, the aim of which was to develop an effective formulation, we evaluated the stability of activated-carbon-encapsulating HSBC gels under various pH conditions. Activated-carbon-encapsulating HSBC gels (ACEGs) retained the activated carbon without leaking when subjected to agitation in acidic or basic environments. The saturated adsorption amount, calculated using the Langmuir adsorption isotherm, was affected by the target adsorbate and pH conditions. These results indicate that ACEGs can adsorb uremic toxins and their precursors similarly to conventional uremic toxin adsorbents while preventing direct contact between the encapsulated activated carbon and the gastrointestinal tract. Compared to powdered activated carbon, the ACEG is less likely to be adsorbed in the gastrointestinal tract. Therefore, the proposed ACEG is a promising new formulation that will contribute to the treatment of renal failure and improve patients' compliance with medication.

3.
Pharmaceutics ; 12(11)2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33187079

RESUMO

For reducing side effects and improvement of swallowing, we studied the encapsulation of activated carbon formulations with a hollow-type spherical bacterial cellulose (HSBC) gel using two kinds of encapsulating methods: Methods A and B. In Method A, the BC gelatinous membrane was biosynthesized using Komagataeibacter xylinus (K. xylinus) at the interface between the silicone oil and cell suspension containing activated carbon. In Method B, the bacterial cellulose (BC) gelatinous membrane was formed at the interface between the cell suspension attached to the alginate gel containing activated carbon and the silicone oil. After the BC gelatinous membrane was biosynthesized by K. xylnus, alginate gel was removed by soaking in a phosphate buffer. The activated carbon encapsulated these methods could neither pass through the BC gelatinous membrane of the HSBC gel nor leak from the interior cavity of the HSBC gel. The adsorption ability was evaluated using indole, which is a precursor of the uremic causative agent. From curve-fitting, the adsorption process followed the pseudo-first-order and intra-particle diffusion models, and the diffusion of the indole molecules at the surface of the encapsulated activated carbon within the HSBC gel was dominant at the initial stage of adsorption. It was observed that the adsorption of the encapsulated activated carbon by the intraparticle diffusion process became dominant with longer adsorption times.

4.
Med Sci Sports Exerc ; 40(7): 1271-6, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18580407

RESUMO

INTRODUCTION: Few studies have reported the response of high-molecular-weight (HMW) adiponectin to acute aerobic exercise. PURPOSE: The purpose of this study was to investigate the influence of acute aerobic exercise on HMW adiponectin in healthy men. METHODS: Eight healthy men (age, 24.9 +/- 1.8 yr; BMI, 21.9 +/- 0.5 kg x m) participated in this study. They performed two trials. Trial 1 [exercise trial (EX)] consisted of 60-min stationary cycle exercise (50% peak oxygen uptake) followed by 30-min rest. Trial 2 [control trial (CON)] was 90-min rest. Blood samples were drawn to assess hormones (catecholamine and insulin), metabolites (free fatty acid [FFA], glycerol, and glucose), and total and HMW adiponectin concentration. RESULTS: There were significant trial x group interactions in serum FFA and glycerol concentrations (P < 0.05). Serum FFA and glycerol concentrations were higher in EX than in CON (P < 0.05). There were significant trial x group interactions in plasma insulin and glucose concentration (P < 0.05). Plasma insulin and glucose concentrations were lower in EX than in CON (P < 0.05). Total adiponectin, HMW adiponectin concentration, and the ratio of HMW to total adiponectin concentration, however, were unchanged during aerobic exercise and postexercise. Also, those changes did not differ between EX and CON. CONCLUSION: Our results indicate that total adiponectin and HMW adiponectin concentrations are not regulated by the change of hormones or metabolites during acute moderate-intensity aerobic exercise and postexercise in healthy young men.


Assuntos
Adiponectina/fisiologia , Catecolaminas/sangue , Exercício Físico/fisiologia , Resistência à Insulina/fisiologia , Insulina/sangue , Adaptação Fisiológica , Adiponectina/química , Análise de Variância , Glicemia/análise , Estudos Cross-Over , Metabolismo Energético , Ácidos Graxos não Esterificados/sangue , Glicerol/sangue , Humanos , Masculino , Consumo de Oxigênio , Estresse Fisiológico , Fatores de Tempo , Adulto Jovem
5.
Life Sci ; 78(11): 1149-54, 2006 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-16442127

RESUMO

A previous study of ours demonstrated that a high-fat diet (FAT) causes body fat accumulation, as well as elevation of plasma leptin level, renal sympathetic nerve activity (RSNA), and blood pressure (BP). In the study reported here, we analyzed the role of leptin in these elevations of the RSNA and BP due to FAT feeding by assessing sympathetic and cardiovascular responses to intravenous (IV) administration of leptin in rats fed either a FAT or a high-carbohydrate diet (CHO). The results showed that baseline body fat, plasma leptin level, RSNA and BP were significantly higher in the FAT group than in the CHO group, and that IV administration of leptin elevated RSNA and plasma leptin levels but lowered BP in the CHO group. However, these effects of leptin were eliminated in the FAT group. These findings suggest that FAT-fed rats which expose basal elevation of plasma leptin levels, RSNA and BP might be hyposensitive to endogenous leptin. Therefore, leptin resistance appeared obviously in FAT-induced hypertension might indicate that leptin is implicated in generating the elevation of RSNA and BP induced by long-term FAT feeding.


Assuntos
Gorduras na Dieta/efeitos adversos , Hipertensão/fisiopatologia , Rim/inervação , Leptina/farmacologia , Sistema Nervoso Simpático/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/efeitos adversos , Gorduras na Dieta/administração & dosagem , Hipertensão/sangue , Hipertensão/etiologia , Infusões Intravenosas , Leptina/administração & dosagem , Leptina/sangue , Masculino , Ratos , Ratos Sprague-Dawley , Sistema Nervoso Simpático/fisiologia
6.
J Bone Miner Res ; 18(1): 140-9, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12510816

RESUMO

To determine both the preventive and recovery effects of tower climbing exercise on mass, strength, and local turnover of bone in ovariectomized (OVX) rats, we carried out two experiments. In experiment I, 60 Sprague-Dawley rats, 12 months of age, were assigned to four groups: a Baseline Control, Sham-Operated Sedentary, OVX-Sedentary and OVX-Exercise rats. Rats voluntarily climbed a 200-cm tower to drink water from a bottle set at the top. At 3 months, OVX elevated both the femoral cortex and lumbar trabecular turnover, leading to a reduction in bone mass and strength. However, in OVX-Exercise rats, those values were maintained at the same level as in the Sham-Sedentary rats. Thus, the climbing exercise, started after 3 days of OVX, prevented OVX-induced cortical and trabecular bone loss by depressing turnover elevation. After confirming the preventive effect, we evaluated the recovery effect of exercise. In experiment II, 90 Sprague-Dawley rats, 12 months of age, were assigned to six groups: a Baseline control, two groups of Sham-Operated Sedentary and OVX-Sedentary, and OVX-Exercise rats. The exercise started 3 months after the OVX operation. At 3 months, OVX increased the trabecular bone formation rate and osteoclast surface, leading to a decrease in compressive strength. In the midfemur, the cross-sectional area, moment of inertia, and bending load values decreased. At 6 months, in the OVX-Exercise rats, the parameters of breaking load in both the lumbar and midfemur, lumbar bone mass, and the total cross-sectional area recovered to the same levels as those in the Sham-Sedentary rats. However, the cortical bone area did not recover. Periosteal bone formation increased, while endosteal bone formation decreased. These results showed that the climbing exercise had both a preventive and recovery effect on bone strength in OVX rats. In the mid-femur, effects on bone formation were site-specific, and the cross-sectional morphology was improved without an increase in cortical bone area, supporting cortical drift by mechanical stimulation.


Assuntos
Doenças Ósseas Metabólicas/terapia , Animais , Fenômenos Biomecânicos , Densidade Óssea , Doenças Ósseas Metabólicas/etiologia , Doenças Ósseas Metabólicas/fisiopatologia , Feminino , Fêmur/fisiopatologia , Vértebras Lombares/fisiopatologia , Osteogênese , Ovariectomia , Condicionamento Físico Animal , Ratos , Ratos Sprague-Dawley , Estresse Mecânico , Fatores de Tempo
7.
Nutr Rev ; 61(5 Pt 2): S88-94, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12828198

RESUMO

This review shows the importance of high-glycemic carbohydrates consumed together with protein in enhancing the exercise-induced muscle formation relative to timing of intake. Insulin, which increases in blood after glycemic carbohydrate ingestion, seems to effectively stimulate protein synthesis and inhibit protein degradation right after exercise rather than later. This presents a new aspect in nutrition: the importance of intake timing in addition to the composition and amount of nutrients.


Assuntos
Aminoácidos/administração & dosagem , Glicemia , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Exercício Físico , Músculo Esquelético/crescimento & desenvolvimento , Tecido Adiposo , Idoso , Envelhecimento , Animais , Composição Corporal , Índice Glicêmico , Humanos , Proteínas Musculares/metabolismo , Esforço Físico
8.
J Appl Physiol (1985) ; 93(3): 1152-8, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12183513

RESUMO

To determine the effects of a tower climbing exercise on mass, strength, and local turnover of bone, 70 9-wk-old Sprague-Dawley rats were assigned to seven groups: a baseline control and three groups of sham-operated sedentary, orchidectomized (ORX)-sedentary and ORX-exercise rats. Rats voluntarily climbed a 200-cm tower to drink water from a bottle set at the top. At 4 wk, the periosteal bone formation rate (BFR), moment of inertia, bone mineral content, bone mineral density, and bending load at the midfemur were maintained in ORX-exercise rats, whereas these parameters were reduced in ORX-sedentary rats. At 8 wk, the periosteal mineral apposition rate and BFR in ORX-exercise rats were significantly higher, whereas the parameters in ORX-sedentary rats did not differ compared with sham-sedentary rats. In ORX-exercise rats, the trabecular mineralizing surface, BFR, and bone volume of the lumbar vertebrae were maintained at the same levels as those in the sham-sedentary group, whereas the osteoclast surface decreased compared with the ORX-sedentary group. However, the climbing exercise did not affect bone mineral content, bone mineral density, or the compression load of the lumbar vertebrae. These results show that, in the midfemur, the voluntary climbing exercise maintained cortical bone mass and strength by stimulating periosteal bone formation and partially prevented ORX-induced trabecular bone loss, depressing the elevation of turnover. Interestingly, in ORX rats, the climbing exercise had the opposite effect on bone formation at the periosteal femoral cortical bone, where the exercise increased the bone formation compared with vertebral trabecular bone, where the exercise decreased it.


Assuntos
Envelhecimento/fisiologia , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Osso e Ossos/fisiologia , Atividade Motora/fisiologia , Orquiectomia , Abdome , Tecido Adiposo/anatomia & histologia , Animais , Biomarcadores , Peso Corporal , Reabsorção Óssea/fisiopatologia , Fêmur/anatomia & histologia , Fêmur/fisiologia , Membro Posterior , Vértebras Lombares/fisiologia , Masculino , Músculo Esquelético/fisiologia , Ratos , Ratos Sprague-Dawley , Resistência à Tração , Fatores de Tempo
9.
J Nutr Biochem ; 15(11): 651-6, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15590268

RESUMO

UNLABELLED: In addition to a signal arising from the physical "stretching" of the adipocytes, metabolic and endocrine regulation of leptin production seems to operate in adipocytes. There is however a paucity of literature examining direct role of fatty acid synthesis in regulating adipocytes leptin production. To clarify the relation between fatty acid synthesis and leptin release in adipocytes, we examined leptin release from primary cultured rat epididymal adipocytes with several substances relevance to de novo fatty acid syntyhesis. Bezafibrate (0.5 or 1.0 mM), known to inhibit acetyl-CoA carboxylase, decreased leptin release to 60.3 +/- 7.2 or 47.3 +/- 11.9%, while cerulenin (15, 30, or 75 mM), an inhibitor of fatty acid synthase, increased it by 20.5 +/- 7.7, 58.5 +/- 12.1 or 105.0 +/- 35.0% of the control. Exogenous pyruvate (2.5, 5.0, or 10.0 mM) and malonyl-CoA (10, 20, or 40 mM), substrates and intermediate of fatty acid synthesis, increased leptin release by 11.0 +/- 3.3, 21.5 +/- 5.4, or 61.0 +/- 10.7%, and 11.1 +/- 3.0, 41.1 +/- 9.7 or 56.7 +/- 7.9% of the control, respectively. Considering difference in the site of action of bezafibrate and cerulenin along fatty acid synthesis pathway, one plausible explanation is that malonyl-CoA levels act as a signal of fuel availability to trigger leptin synthesis and/or secretion in adipocytes. KEYWORDS: Leptin secretion; Fatty acid synthesis; Malonyl-CoA; Rat adipocytes.


Assuntos
Adipócitos/metabolismo , Leptina/biossíntese , Adipócitos/efeitos dos fármacos , Animais , Bezafibrato/farmacologia , Cerulenina/farmacologia , Epididimo/citologia , Ácidos Graxos/biossíntese , Técnicas In Vitro , Ácido Láctico/farmacologia , Masculino , Malonil Coenzima A/metabolismo , Malonil Coenzima A/farmacologia , Ácido Pirúvico/farmacologia , Ratos
10.
Life Sci ; 71(5): 537-46, 2002 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-12052438

RESUMO

The elevation of renal sympathetic nervous activity (SNA) is a possible cause of blood pressure (BP) elevation. Although a high-fat diet (FAT) often induces BP elevation in animals, the effect of FAT on renal SNA in animals is not consistent between studies. Thus, we compared the basal levels of efferent renal SNA and BP in FAT- or high-carbohydrate diet (CHO)-fed rats. Twenty-four male Sprague-Dawley rats were fed FAT (P/F/C=20/45/35% cal) or CHO (20/5/75) from 5 weeks of age. After 20-21 weeks of feeding, a 24-h urine sample was collected to measure sodium excretion. The next day, blood (0.2 ml) was withdrawn from a femoral artery, and basal efferent renal nerve discharges and mean arterial pressure (MAP) were recorded under anesthesia. Immediately after the experiment, abdominal (epididymal, perirenal and mesenteric) adipose tissues were dissected. Total abdominal fat weight was significantly greater in the FAT group than in the CHO group. The plasma level of leptin was significantly higher in the FAT group, but blood glucose and plasma insulin levels did not differ between the two groups. MAP and renal SNA were significantly higher in the FAT group. In addition, the ratio of urinary sodium excretion to dietary sodium intake was significantly lower in the FAT group than in the CHO group. The data suggest that the increased renal SNA may contribute to BP elevation in FAT-fed rats. The present study firstly demonstrated that renal SNA was elevated with FAT-related BP elevation.


Assuntos
Gorduras na Dieta/administração & dosagem , Hipertensão/fisiopatologia , Rim/inervação , Sistema Nervoso Simpático/fisiologia , Animais , Pressão Sanguínea/fisiologia , Peso Corporal , Carboidratos da Dieta/administração & dosagem , Frequência Cardíaca/fisiologia , Leptina/sangue , Masculino , Ratos , Ratos Sprague-Dawley , Sódio/urina
11.
J Nutr Sci Vitaminol (Tokyo) ; 48(2): 109-14, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12171430

RESUMO

Triacylglycerols containing medium- and long-chain fatty acids (TML) have medium- and long-chain fatty acids in the same molecule. The effects of dietary TML on serum lipid levels and body fat were studied in six young men belonging to a university rowing club. A double-blind crossover study was performed in which for 3 wk the subjects ingested a liquid diet containing 20 g/d of soybean oil or TML in addition to their regular diets. Throughout the study, they were asked to keep their usual lifestyle, including diet and physical activity. The body composition of the subjects was measured weekly. Blood samples were taken at 0, 2, and 3 wk of each treatment period. There was no significant difference in energy intake between the soybean oil diet period and the TML diet period. The rate of variation of serum triacylglycerol concentration was significantly lower after a consumption of the TML liquid diet for 3 wk compared with the soybean oil liquid diet. The rate of variation of body fat mass was also significantly lower after a consumption of the TML liquid diet for 3 wk compared with the soybean oil liquid diet. However, the serum cholesterol concentration did not change significantly during either dietary treatment. These results suggest that TML, compared with soybean oil, may have the potential to prevent hypertriglyceridemia and obesity caused by consumption of a high-fat diet.


Assuntos
Tecido Adiposo/metabolismo , Composição Corporal/efeitos dos fármacos , Gorduras na Dieta/farmacologia , Esportes/fisiologia , Triglicerídeos/sangue , Triglicerídeos/farmacologia , Adolescente , Adulto , Colesterol/sangue , Estudos Cross-Over , Método Duplo-Cego , Humanos , Masculino , Óleo de Soja/química , Óleo de Soja/farmacologia , Triglicerídeos/química
12.
J Nutr Sci Vitaminol (Tokyo) ; 48(2): 161-4, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12171438

RESUMO

To evaluate the effects of long-term voluntary resistance exercise (climbing) compared with aerobic exercise (swimming) on iron status in severely (4 mg Fe/kg diet) and mildly (18-29 mg Fe/kg diet) iron-deficient rats, we trained male Wistar rats for 8 wk to climb a wire-mesh tower (phi20 cm x 200 cm, CLIMB) and to swim in a plastic pool (phi50 cm x 50 cm, SWIM). These rats were compared with sedentary (SED) rats. After the experimental period, blood hemoglobin level, plasma iron concentration, and transferrin saturation were significantly lower in the 4 mg Fe/kg diet rats than in the 18, 29, and 40 mg Fe/kg diet rats. In 4 mg Fe/kg diet rats, the hemoglobin level was significantly higher in the CLIMB group than in the SED and SWIM groups. On the other hand, neither exercise affected iron status in mildly iron-deficient rats. Bone marrow delta-aminolevulinic acid dehydratase activity was significantly higher in the CLIMB group than in the SWIM and SED groups. These results suggest that long-term resistance exercise is more effective than aerobic exercise in improving blood hemoglobin concentration in severely iron-deficient rats, probably because of an increase in heme biosynthesis. Resistance exercise may be a useful therapy for iron-deficient anemia.


Assuntos
Heme/biossíntese , Hemoglobinas/metabolismo , Deficiências de Ferro , Ferro da Dieta/administração & dosagem , Condicionamento Físico Animal/fisiologia , Animais , Medula Óssea/enzimologia , Relação Dose-Resposta a Droga , Ferro/sangue , Ferro/metabolismo , Masculino , Sintase do Porfobilinogênio/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Natação/fisiologia , Fatores de Tempo , Transferrina/metabolismo
13.
Bone ; 65: 42-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24815919

RESUMO

Maximizing peak bone mass is an important factor in osteoporosis prevention. Resistance exercise increases bone mass and strength, while nutritional supplements have beneficial effects on bone loss reduction. We have previously shown that the combined intake of sucrose and amino acids (AA), which is strongly insulinogenic, efficiently increased muscle protein synthesis. To investigate the effects of sugar and an AA solution immediately after resistance exercise, we compared insulinogenic sucrose and non-insulinogenic fructose combined with an AA solution with or without resistance exercise. Sucrose intake immediately after resistance exercise increased the trabecular bone mass and compressive maximum load compared with fructose+AA intake after exercise. Additionally, combined sucrose+AA and exercise increased trabecular bone formation and decreased bone resorption more than combined fructose and exercise. Serum insulin levels were greatly increased by sucrose+AA intake with exercise. In culture experiments, neither sugar+AA affected osteoblast and osteoclast differentiation. In a gene expression study, sucrose+AA intake after resistance exercise was shown to upregulate the Runx2 expression level and decrease RANKL/OPG ratio. These results suggest that the combined intake of sucrose and an AA solution immediately after resistance exercise exerts anabolic effects on bone by altering gene expression related to bone remodeling. Although translation of our bone remodeling findings from animal to human studies has been challenging, our findings suggest that exercise with sugar+AA intake may contribute to improved bone health.


Assuntos
Aminoácidos/administração & dosagem , Osso e Ossos/fisiologia , Frutose/administração & dosagem , Insulina/biossíntese , Condicionamento Físico Animal , Sacarose/administração & dosagem , Células 3T3 , Absorciometria de Fóton , Animais , Sequência de Bases , Densidade Óssea , Primers do DNA , Camundongos , Ratos , Reação em Cadeia da Polimerase em Tempo Real
14.
J Nutr Sci Vitaminol (Tokyo) ; 57(3): 233-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21908946

RESUMO

We have previously reported on the possibility that light resistance exercise performed with a high plasma amino acid concentration resulting from the ingestion of a high-protein snack (HPS; 15 g protein, 18 g sugar) 3 h after a basal meal promotes the utilization of amino acids in peripheral tissues such as muscle in both rats and humans. In the present study, we further examined the effectiveness of a daily routine involving ingestion of HPS 3 h after a basal meal and subsequent light resistance exercise (dumbbell exercise) in increasing the mass and strength of human muscle. Ten young adult males were subject to the following 3 conditions for 5 wk each, with sufficient recovery period between each condition: (1) Snack-Exercise (SE), (2) Snack-Sedentary (SS), and (3) No snack-Exercise (NE). The SE group showed a significant increase in lean body mass and total cross-sectional area (CSA) of the right forearm muscles along with a significant decrease in body fat mass. The SS group showed no change in body composition. Furthermore, the SE group showed significant increase in grip strength and isometric knee extensor muscle strength, while the SS group showed no increase in muscle strength. The NE group showed significant increase in grip strength. In conclusion, daily routine ingestion of HPS 3 h after a basal meal and subsequent light resistance exercise is effective in increasing the mass and strength of human muscle.


Assuntos
Composição Corporal , Dieta , Proteínas Alimentares/farmacologia , Exercício Físico/fisiologia , Força Muscular , Músculo Esquelético/fisiologia , Treinamento Resistido , Tecido Adiposo , Adulto , Compartimentos de Líquidos Corporais , Força da Mão , Humanos , Joelho , Articulação do Joelho , Masculino , Tamanho do Órgão , Adulto Jovem
15.
J Nutr Sci Vitaminol (Tokyo) ; 56(4): 255-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20924148

RESUMO

The study investigated exercise patterns resulting in the more efficient promotion of amino acid utilization. High-protein snacks (HPS; 15 g protein, 18 g sugar) were ingested by 8 young adult subjects 3 h after the basal meal ingestion. Sixty minutes after the HPS ingestion, the subjects performed arm flex/extend exercises for 15 min. The difference between 2 exercise patterns was compared. Pattern 1: High-number long-interval (HL) arm flex/extend (3+3 s) exercise; the HL group performed 9 sets of 15 exercises with a 10 s interval between sets. Pattern 2: Low-number short-interval (LS) arm flex/extend (3+3 s) exercise; the LS group performed 27 sets of 5 exercises with a 3-4 s interval between sets (135 exercises during 15 min, respectively). The plasma branched-chain amino acid (BCAA) concentrations were measured before the HPS ingestion, before the exercise, and 60 and 90 min after the HPS ingestion. The plasma BCAA concentrations increased significantly after the HPS ingestion. In the HL group, BCAA concentration increased consistently during the period and 60 to 90 min after the HPS ingestion. During the same period in the LS group the BCAA concentration stopped increasing. After HPS ingestion, a significantly greater suppressive effect on plasma BCAA concentration was seen in the LS group compared to the HL group. Results confirmed that the intermittent blood volume fluctuation in muscle tissue during the exercise pattern performed by the LS group had an effect on the utilization of nutritional components (BCAA, glucose) from the blood, and showed the possibility that the group where the blood volume in the muscle tissue increased/lowered with higher frequency was a more effective exercise pattern for nutrient utilization.


Assuntos
Aminoácidos/sangue , Volume Sanguíneo/fisiologia , Proteínas Alimentares/farmacologia , Contração Muscular/fisiologia , Músculo Esquelético/irrigação sanguínea , Treinamento Resistido , Adulto , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
16.
J Nutr Sci Vitaminol (Tokyo) ; 56(5): 299-304, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21228500

RESUMO

The purpose of this study was to elucidate the fat-loading effect of the classic 1-wk glycogen-loading regimen histologically in rats and physiologically in humans. In the rat and human studies, an exhaustive swimming exercise and cycle ergometer exercise were loaded on day 1 of a 6-d feeding period, respectively. Thereafter, both the rats and humans were divided into a glycogen-loading regimen consisting of a 3-d high-fat diet and a 3-d high-carbohydrate diet or a 6-d high-carbohydrate diet. After the feeding period in the human study, the human subjects performed a test exercise on day 7 using a cycle ergometer. In the rat study, the intramuscular triglyceride (IMTG) content was 69% greater (p<0.05) after the glycogen-loading regimen than after the high-carbohydrate diet feeding on day 7. In the human study, the respiratory exchange ratios (RER) after the glycogen-loading regimen were 4.9-6% lower than those after the high-carbohydrate diet during the test exercise on day 7 (p<0.05). Our findings suggest that the classical 1-wk glycogen-loading regimen maintained the storage and enhanced the utilization of energy sources during exercise in the skeletal muscle, and that it provides a fat-loading effect, in addition to the glycogen-loading effect, to the skeletal muscle.


Assuntos
Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Glicogênio/metabolismo , Músculo Esquelético/metabolismo , Adolescente , Adulto , Animais , Glicemia/análise , Estudos Cross-Over , Carboidratos da Dieta/metabolismo , Gorduras na Dieta/metabolismo , Metabolismo Energético , Teste de Esforço , Humanos , Masculino , Consumo de Oxigênio , Ratos , Ratos Wistar , Triglicerídeos/metabolismo , Adulto Jovem
17.
Arch Oral Biol ; 54(11): 977-85, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19735909

RESUMO

OBJECTIVE: The purpose of the study was to assess the alterations of the autonomic nervous system activities caused by physical exercise training under food restriction using a running wheel in mice based on an analysis of saliva. METHODS: Male ICR mice, weighing 39-50 g, at 32 weeks of age were divided into three groups; an exercise with food restriction (EXP), an exercise without food restriction (EXA) and a control (CTL). The EXP group was fed the same amount of diet as the CTL group (pair-feeding). The EXP and EXA groups used a "voluntary running wheel" for exercise. The pilocarpine stimulated whole saliva was collected from the oral cavity by micropipette over 15 min 4, 8 and 12 weeks after the beginning of the experiment. The salivary flow rate, protein concentration and amylase and kallikrein activities were determined, since amylase and kallikrein release have been shown to be evoked by beta- and alpha-adrenergic receptor stimulation, respectively. RESULTS: There was no significant difference in the sera corticosterone levels among the three experimental groups. The flow rate of saliva per total salivary gland weight in the EXP was significantly lower than that in the CTL and the EXA groups. The total protein secretion and kallikrein activity decreased by 20-30% in the EXP mice between 4 and 12 weeks after the starting of experiments in comparison to the CTL mice, thus suggesting that signal transduction in the alpha-sympathetic nervous system was downregulated. There was no significant difference in the amylase activity between the EXP and the CTL groups. CONCLUSION: Physical exercise under diet control induced alterations in saliva secretion, while exercise training alone did not affect the content of saliva. The results demonstrate the availability of saliva and suggest that the present experimental situation is a suitable experimental model for sports activity performed under diet control.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Restrição Calórica , Condicionamento Físico Animal/fisiologia , Receptores Adrenérgicos alfa/biossíntese , Saliva/metabolismo , Amilases/biossíntese , Animais , Corticosterona/sangue , Calicreínas/biossíntese , Camundongos , Camundongos Endogâmicos ICR , Modelos Animais , Tamanho do Órgão , Saliva/química , Glândulas Salivares/anatomia & histologia , Glândulas Salivares/inervação , Proteínas e Peptídeos Salivares/análise , Taxa Secretória
18.
J Nutr Sci Vitaminol (Tokyo) ; 55(2): 106-11, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19436135

RESUMO

We have previously reported the preventive effects of light resistance exercise (voluntary tower climbing exercise) after ingestion of a high-protein snack (HPS) on muscle loss in glucocorticoid-injected rats. However, such studies have not been performed in humans. In this cross-over study, we examined the effect of light resistance exercise after ingestion of HPS on plasma branched-chain amino acid (BCAA) concentrations in humans. Seven healthy young adult females (aged 22.1+/-1.2 y) participated in this study. They were assigned to either an exercise group or a control group. Seven days after the first experiment, they were crossed over to the opposite intervention. The subjects ingested HPS (15 g protein, 18 g sugar) 3 h after breakfast (basal meal). The plasma BCAA concentrations increased at 30 min after HPS ingestion. The subjects in the exercise group performed light resistance exercise (15 min dumbbell exercise using 300 g brown-rice-filled fabric dumbbells) when the plasma BCAA concentrations were increased (60 min after the snack ingestion). The control group maintained a resting position during the experiment. Changes in the plasma BCAA concentrations between 60 and 90 min after HPS ingestion increased continuously in the control group (+27 micromol/L) but decreased in the exercise group (-37 micromol/L). Therefore, light resistance exercise after HPS ingestion may be effective for utilization of plasma BCAA in humans.


Assuntos
Aminoácidos de Cadeia Ramificada/sangue , Proteínas Alimentares/farmacologia , Exercício Físico/fisiologia , Treinamento Resistido , Estudos Cross-Over , Feminino , Humanos , Músculo Esquelético/fisiologia , Adulto Jovem
19.
Biosci Biotechnol Biochem ; 69(10): 1819-23, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16244429

RESUMO

We examined the effects of ingesting a non-sugar chocolate containing polydextrose and lactitol in place of sucrose and lactose on the concentrations of plasma glucose and serum insulin and triglyceride in humans. A regular chocolate was used as the control. A crossover study was employed, and the subjects each ingested 46 g of the control or non-sugar chocolate in the experiments. Alterations in the blood components were monitored for a period of 150 min after ingestion. The control chocolate elevated the concentrations of plasma glucose and serum insulin, with the peak occurring 30 min after ingestion, but the non-sugar chocolate had a very minor effect. The serum triglyceride concentration gradually increased after ingesting the control chocolate, but was only slightly elevated 150 min after ingesting the non-sugar chocolate. An animal study also showed an attenuated response of serum triglyceride to the administration of a fat emulsion containing polydextrose and lactitol, suggesting that the triglyceride transit through the gut was promoted by these compounds. These results suggest that, compared to regular chocolate, fat absorption in the gut was less after ingesting the non-sugar chocolate, presumably resulting in less effect on body fat deposition.


Assuntos
Cacau/química , Glucanos/farmacocinética , Álcoois Açúcares/farmacocinética , Edulcorantes/farmacocinética , Triglicerídeos/sangue , Adulto , Animais , Glicemia , Cacau/metabolismo , Glucanos/administração & dosagem , Glucanos/farmacologia , Humanos , Insulina/sangue , Absorção Intestinal , Intestino Delgado/metabolismo , Masculino , Farmacocinética , Ratos , Álcoois Açúcares/administração & dosagem , Álcoois Açúcares/farmacologia , Edulcorantes/administração & dosagem , Edulcorantes/farmacologia
20.
Asia Pac J Clin Nutr ; 13(3): 242-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15331335

RESUMO

The effects of light resistance exercise using dumbbells and rubber band with mild energy restriction on body composition and physical fitness were studied in 11 mildly obese Korean women aged 38-59 years. The subjects performed dumbbell exercises with pairs of 0.5-1 kg dumbbells and rubber band exercise 3 days per week for approximately 40 min. Subjects were restricted to approximately 80% of energy intake RDA for Korean women for 12 weeks. Subjects were measured for body composition, physical fitness, and blood and serum biochemical data before commencing the experiment and again at 12 weeks while still dieting. During the 12-week experimental period, body weight and body fat decreased significantly without reducing fat free mass. Grip and back strength increased significantly during the experimental period. These results suggest that combination of dumbbell and rubber band exercises decreases body weight and body fat without reducing FFM while increasing physical fitness.


Assuntos
Composição Corporal/fisiologia , Dieta Redutora , Obesidade/terapia , Aptidão Física , Levantamento de Peso/fisiologia , Tecido Adiposo/metabolismo , Adulto , Feminino , Humanos , Coreia (Geográfico) , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Obesidade/dietoterapia
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