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Previous studies demonstrated that resveratrol (RES) is able to enhance antioxidant, anti-inflammatory and insulin actions in humans. It is unclear whether RES can be used as ergogenic aids to enhance high-intensity cycling exercise performance and attenuate the high-intensity exercise-induced oxidative stress and inflammation. This study investigated the effect of RES supplementation on oxidative stress, inflammation, exercise-induced fatigue, and endurance performance. Eight male athletes participated in this single-blind crossover designed study and randomly instructed to receive four days of either oral RES (480 mg per day, totally 1920mg) or placebo supplementation. The cycling exercise challenge at 80% maximal oxygen consumption with 60 rpm was performed following 4 days of either RES or placebo supplementation. The total cycling performance time was recorded. In addition, blood samples were obtained to analyze the changes in blood glucose, plasma non-esterified fatty acid, serum lactate dehydrogenase, creatine kinase, uric acid, total antioxidant capacity, malondialdehyde, tumor necrosis factor-α, and interleukin-6. The exhausting time of cycling exercise challenge was not significantly increased in RES compared to that in placebo. However, IL-6 response was significantly decreased during exercise challenge in RES trial, and there were no differences in blood biomarkers, fatigue factors, and antioxidative response. Oral RES supplementation can attenuate exercise-induced IL-6 response but not fatigue and oxidative stress, inflammation response. However, we infer that 4-day oral RES supplementation has no ergogenic property on enhancing the high-intensity cycling exercise performance.
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Ciclismo/fisiología , Fatiga/diagnóstico , Interleucina-6/sangre , Sustancias para Mejorar el Rendimiento/administración & dosificación , Resveratrol/administración & dosificación , Administración Oral , Adolescente , Atletas , Rendimiento Atlético/fisiología , Estudios Cruzados , Fatiga/sangre , Fatiga/inmunología , Fatiga/prevención & control , Humanos , Inflamación/sangre , Inflamación/inmunología , Inflamación/prevención & control , Interleucina-6/metabolismo , Masculino , Estrés Oxidativo/efectos de los fármacos , Método Simple Ciego , Resultado del Tratamiento , Adulto JovenRESUMEN
The purpose of this study was to investigate the effects of 8-week green tea extract (GTE) supplementation on promoting postexercise muscle glycogen resynthesis and systemic energy substrate utilisation in young college students. A total of eight healthy male participants (age: 22·0 (se 1·0) years, BMI: 24·2 (se 0·7) kg/m2, VO2max: 43·2 (se 2·4) ml/kg per min) participated in this study. GTE (500 mg/d for 8 weeks) was compared with placebo in participants in a double-blind/placebo-controlled and crossover study design with an 8-week washout period. Thereafter, all participants performed a 60-min cycling exercise (75 % VO2max) and consumed a carbohydrate-enriched meal immediately after exercise. Vastus lateralis muscle samples were collected immediately (0 h) and 3 h after exercise, and blood and gaseous samples were collected during the 3-h postexercise recovery period. An 8-week oral GTE supplementation had no effects on further promoting muscle glycogen resynthesis in exercised human skeletal muscle, but the exercise-induced muscle GLUT type 4 (GLUT4) protein content was greater in the GTE supplementation trial (P<0·05). We observed that, during the postexercise recovery period, GTE supplementation elicited an increase in energy reliance on fat oxidation compared with the placebo trial (P<0·05), although there were no differences in blood glucose and insulin responses between the two trials. In summary, 8-week oral GTE supplementation increases postexercise systemic fat oxidation and exercise-induced muscle GLUT4 protein content in response to an acute bout of endurance exercise. However, GTE supplementation has no further benefit on promoting muscle glycogen resynthesis during the postexercise period.
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Ejercicio Físico/fisiología , Glucógeno/metabolismo , Músculo Esquelético/fisiología , Extractos Vegetales/farmacología , Té/química , Área Bajo la Curva , Glucemia , Humanos , Insulina/sangre , Masculino , Extractos Vegetales/química , Adulto JovenRESUMEN
The central nervous system plays a crucial role in fatigue during endurance exercise. Branched-chain amino acids (BCAA) could reduce cerebral serotonin synthesis by competing with its precursor tryptophan for crossing the blood brain barrier. Arginine and citrulline could prevent excess hyperammonemia accompanied by BCAA supplementation. This study investigated the combination of BCAA, arginine, and citrulline on endurance performance in two consecutive days. Seven male and three female endurance runners ingested 0.17 g·kg-1 BCAA, 0.05 g·kg-1 arginine and 0.05 g·kg-1 citrulline (AA trial) or placebo (PL trial) in a randomized cross-over design. Each trial contained a 5000 m time trial on the first day, and a 10000 m time trial on the second day. The AA trial had significantly better performance in 5000 m (AA: 1065.7 ± 33.9 s; PL: 1100.5 ± 40.4 s) and 10000 m (AA: 2292.0 ± 211.3 s; PL: 2375.6 ± 244.2 s). The two trials reported similar ratings of perceived exertion. After exercise, the AA trial had significantly lower tryptophan/BCAA ratio, similar NH3, and significantly higher urea concentrations. In conclusion, the supplementation could enhance time-trial performance in two consecutive days in endurance runners, possibly through the inhibition of cerebral serotonin synthesis by BCAA and the prevention of excess hyperammonemia by increased urea genesis.
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Present study examined the effects of conjugated linoleic acid (CLA) supplementation on glycogen resynthesis in exercised human skeletal muscle. Twelve male participants completed a cross-over trial with CLA (3.8 g/day for 8 week) or placebo supplements by separation of 8 weeks. CLA is a mixture of trans-10 cis-12 and cis-9 trans-11 isomers (50:50). On experiment day, all participants performed 60-min cycling exercise at 75% VO2 max, then consumed a carbohydrate meal immediately after exercise and recovered for 3 h. Biopsied muscle samples from vastus lateralis were obtained immediately (0 h) and 3 h following exercise. Simultaneously, blood and gaseous samples were collected for every 30 min during 3-h recovery. Results showed significantly increased muscle glycogen content with CLA after a single bout of exercise (P < 0.05). Muscle glucose transporter type 4 expression was significantly elevated immediately after exercise, and this elevation was continued until 3 h after exercise in CLA trial. However, P-Akt/Akt ratio was not significantly altered, while glucose tolerance was impaired with CLA. Gaseous exchange data showed no beneficial effect of CLA on fat oxidation, instead lower non-esterified fatty acid and glycerol levels were found at 0 h. Our findings conclude that CLA supplementation can enhance the glycogen resynthesis rate in exercised human skeletal muscle.
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Suplementos Dietéticos , Ejercicio Físico/fisiología , Glucógeno/biosíntesis , Ácidos Linoleicos Conjugados/administración & dosificación , Músculo Esquelético/metabolismo , Glucemia/metabolismo , Estudios Cruzados , Ácidos Grasos no Esterificados/metabolismo , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Transportador de Glucosa de Tipo 4/metabolismo , Homeostasis , Humanos , Insulina/sangre , Masculino , Proteínas Serina-Treonina Quinasas/metabolismo , Ventilación Pulmonar , Adulto JovenRESUMEN
PURPOSE: Garlic extract (GA) is purported to enhance antioxidant and anti-inflammatory activity and glucose regulation in humans. The present study investigated the effects of post-exercise GA supplementation on GLUT4 expression, glycogen replenishment, and the transcript factors involved with mitochondrial biosynthesis in exercised human skeletal muscle. METHODS: The single-blinded crossover counterbalanced study was completed by 12 participants. Participants were randomly divided into either GA (2000 mg of GA) or placebo trials immediately after completing a single bout of cycling exercise at 75% Maximal oxygen uptake (VO2max) for 60 minutes. Participants consumed either GA (2000 mg) or placebo capsules with a high glycemic index carbohydrate meal (2 g carb/body weight) immediately after exercise. Muscle samples were collected at 0-h and 3-h post-exercise. Muscle samples were used to measure glycogen levels, GLUT4 protein expression, as well as transcription factors for glucose uptake, and mitochondria biogenesis. Plasma glucose, insulin, glycerol, non-esterified fatty acid (NEFA) concentrations, and respiratory exchange ratio (RER) were also analyzed during the post-exercise recovery periods. RESULTS: Skeletal muscle glycogen replenishment was significantly elevated during the 3-h recovery period for GA concurrent with no difference in GLUT4 protein expression between the garlic and placebo trials. PGC1-α gene expression was up-regulated for both GA and placebo after exercise (p < 0.05). Transcript factors corresponding to muscle mitochondrial biosynthesis were significantly enhanced under acute garlic supplementation as demonstrated by TFAM and FIS1. However, the gene expression of SIRT1, ERRα, NFR1, NFR2, MFN1, MFN2, OPA1, Beclin-1, DRP1 were not enhanced, nor were there any improvements in GLUT4 expression, following post-exercise garlic supplementation. CONCLUSION: Acute post-exercise garlic supplementation may improve the replenishment of muscle glycogen, but this appears to be unrelated to the gene expression for glucose uptake and mitochondrial biosynthesis in exercised human skeletal muscle.
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Ajo , Glucógeno , Humanos , Glucógeno/metabolismo , Antioxidantes/metabolismo , Ajo/metabolismo , Transportador de Glucosa de Tipo 4/genética , Transportador de Glucosa de Tipo 4/metabolismo , Glucosa/metabolismo , Músculo Esquelético , Suplementos Dietéticos , ARN Mensajero/metabolismo , Mitocondrias/metabolismo , Glucemia/metabolismoRESUMEN
BACKGROUND: Garlic extract has been shown to enhance antioxidant and anti-inflammation activities in humans. The present study investigated the effects of garlic supplementation on 40-km cycling time trial performance, exercise-induced oxidative stress, and inflammatory responses in healthy adults. METHODS: Eleven healthy males were recruited to perform this single-blind crossover study. Participants were randomly assigned to either garlic (garlic extracts 1000 mg/d for 4 weeks) or placebo trials. Following 4-wks of supplementation, participants performed a 40-km cycling challenge. Total cycling performance time and respiratory exchange ratio (RER) were recorded. Blood samples were collected every 10 km to determine exercise-induced oxidative stress, inflammation, and muscle damage. RESULTS: The 40-km cycling time trial performance was not improved following 4 weeks of garlic supplementation. However, 4-wk garlic supplementation significantly increased whole-body antioxidant capacity (total antioxidant capacity, TAC), and subsequently attenuated MDA, TNF-α, and LDH during the 40-km cycling exercise period (p < 0.05). There were no significant differences among the blood biomarkers glucose, NEFA, IL-6, UA, and CK respectively. The respiratory exchange ratio was similar between garlic and placebo trials. CONCLUSION: Four-week oral garlic supplementation attenuates exercise-induced oxidative inflammation and muscle damage during a 40-km bout of cycling. However, it appeared that 4-wk oral garlic had no ergogenic effect on cycling performance in healthy males.
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Antioxidantes , Ajo , Masculino , Humanos , Adulto , Antioxidantes/farmacología , Suplementos Dietéticos , Estudios Cruzados , Método Simple Ciego , Estrés Oxidativo , Inflamación , Método Doble CiegoRESUMEN
Glycogen stored in skeletal muscle is the main fuel for endurance exercise. The present study examined the effects of oral hydroxycitrate (HCA) supplementation on post-meal glycogen synthesis in exercised human skeletal muscle. Eight healthy male volunteers (aged 22·0 (se 0·3) years) completed a 60-min cycling exercise at 70-75 % VO2max and received HCA or placebo in a crossover design repeated after a 7 d washout period. They consumed 500 mg HCA or placebo with a high-carbohydrate meal (2 g carbohydrate/kg body weight, 80 % carbohydrate, 8 % fat, 12 % protein) for a 3-h post-exercise recovery. Muscle biopsy samples were obtained from vastus lateralis immediately and 3 h after the exercise. We found that HCA supplementation significantly lowered post-meal insulin response with similar glucose level compared to placebo. The rate of glycogen synthesis with the HCA meal was approximately onefold higher than that with the placebo meal. In contrast, GLUT4 protein level after HCA supplementation was significantly decreased below the placebo level, whereas expression of fatty acid translocase (FAT)/CD36 mRNA was significantly increased above the placebo level. Furthermore, HCA supplementation significantly increased energy reliance on fat oxidation, estimated by the gaseous exchange method. However, no differences were found in circulating NEFA and glycerol levels with the HCA meal compared with the placebo meal. The present study reports the first evidence that HCA supplementation enhanced glycogen synthesis rate in exercised human skeletal muscle and improved post-meal insulin sensitivity.
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Citratos/administración & dosificación , Suplementos Dietéticos , Ejercicio Físico/fisiología , Glucógeno/biosíntesis , Músculo Esquelético/metabolismo , Secuencia de Bases , Ciclismo/fisiología , Antígenos CD36/genética , Antígenos CD36/metabolismo , Estudios Cruzados , Garcinia cambogia , Glucosa/metabolismo , Transportador de Glucosa de Tipo 4/genética , Transportador de Glucosa de Tipo 4/metabolismo , Humanos , Resistencia a la Insulina/fisiología , Masculino , Medicina Tradicional de Asia Oriental , Periodo Posprandial , ARN Mensajero/genética , ARN Mensajero/metabolismo , Adulto JovenRESUMEN
Aim: Quercetin has been reported to have antioxidant and anti-inflammatory properties on health promotion in human studies. The main purpose of this study was to investigate the effect of short-term oral quercetin supplementation on post-exercise whole-body energy metabolism. This study also aimed to determine the effects of supplementation on oxygen stress, inflammation, muscle damage, and high-intensity cycling exercise performance. Method: Twelve healthy participants, physically active students, were recruited to perform a randomized, single-blind crossover study. All subjects completed 7-days of quercetin (quercetin:1,000 mg per day for 7-days) and placebo supplementation in a randomized order. Supplement/placebo was combined with exercise consisting of 70% VÌO2max cycling for 60-min, followed by 3-h of recovery, then a subsequent single bout of cycling exercise with 75% VÌO2max to exhaustion. Time to exhaustion, indicators of muscle damage, as well as blood and gaseous parameters relating to energy metabolism, oxidative stress, inflammatory response, respectively, were determined. Results: The results showed that 7-day quercetin supplementation significantly attenuated the post-exercise glucose-induced insulin response, increased total antioxidant capacity (TAC) and superoxidase dismutase (SOD) activities, and mitigated malondialdehyde (MDA) levels during the recovery period (p < 0.05). While subsequent 75% VÌO2max cycling performance was significantly improved after quercetin treatment and accompanied by lower responses of interleukin 6 and creatine kinase at 24-h. However, it's noted that there were no significant responses in glucose, respiratory exchange rate, tumor necrosis factor-α (TNF-α), myoglobin, and high sensitivity C-reactive protein between quercetin and placebo trials. Conclusion: Our findings concluded that 7-day oral quercetin supplementation enhances high-intensity cycling time to exhaustion, which may be due in part to the increase in whole-body insulin-stimulated glucose uptake and attenuation of exercise-induced oxygen stress and pro-inflammation. Therefore, quercetin may be considered an effective ergogenic aid for enhancing high-intensity cycling performance among young adults.
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Diabetes is characterized by elevated blood glucose levels and disturbed homeostasis of metabolic enzymes in whole-body. This study aimed to investigate the effect of ginger administration on altered blood glucose levels, intra- and extra-mitochondrial enzymes and tissue injuries in streptozotocin (STZ)-induced diabetic rats. Wistar strain rats (n = 30) were equally divided into 5 groups: normal control (NC), ginger treated (Gt, 200 mg/kg b.w. orally/30 days), diabetic control (DC, 50 mg/kg b.w.), diabetic plus ginger treated (D + Gt) and diabetic plus glibenclamide treated (D + Gli) groups. We found highly elevated blood glucose levels in the diabetic group, and the glucose levels were significantly (P < 0.001) lowered by ginger administration. Activities of intra- and extra-mitochondrial enzymes such as glucose-6-phosphate dehydrogenase (G6PD), succinate dehydrogenase (SDH), malate dehydrogenase (MDH) and glutamate dehydrogenase (GDH) were significantly (P < 0.01) decreased in the kidneys of the diabetic rats, while this was significantly reversed by 30 days of ginger treatment. We also observed consistent renal tissue damages in the diabetic rats; however, these injuries recovered in the ginger-treated diabetic rats as shown in histopathological studies. In this study, we demonstrated that an ethanolic extract of ginger could lower the blood glucose levels as well as improve activities of intra- and extra-mitochondrial enzymes in diabetic rats. Our results suggest that ginger extracts could be used as a nephro-protective supplement particularly to reverse diabetic-induced complications.
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Diabetes Mellitus Experimental/tratamiento farmacológico , Nefropatías Diabéticas/prevención & control , Riñón/efectos de los fármacos , Extractos Vegetales/farmacología , Zingiber officinale , Animales , Glucemia/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Citosol/efectos de los fármacos , Citosol/enzimología , Diabetes Mellitus Experimental/metabolismo , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Modelos Animales de Enfermedad , Riñón/metabolismo , Riñón/patología , Masculino , Mitocondrias/efectos de los fármacos , Mitocondrias/enzimología , Ratas , Ratas WistarRESUMEN
BACKGROUND: Capsinoids (CSN), the novel non-pungent capsaicin analogs have been reported to promote metabolic health and exercise tolerance. However, the effect of CSN on fat oxidation and changes in skeletal muscle glycogen levels during post-exercise recovery has not been investigated in humans. PURPOSE: We examined the effect of CSN supplementation on energy reliance, glycogen resynthesis and molecular proteins in the skeletal muscle of young adults during post-exercise recovery. METHODS: In this crossover-designed study, nine healthy adult male volunteers (aged 21.4±0.2 years, BMI 21.9±1.3 kg/m2) completed a 60-min cycling exercise at 70% VO2max. Participants consumed either CSN (12 mg, single dosage) or placebo capsules with a high-carbohydrate meal (2 g carb/kg bodyweight) immediately after exercise. Biopsied muscle samples (vastus lateralis), blood, and gaseous samples were obtained during 3h postexercise recovery period. RESULTS: We found that oral CSN supplementation right after exercise significantly altered the energy reliance on fat oxidation during recovery. This was evidenced by lower respiratory exchange ratio (RER) and higher fat oxidation rate in CSN trial. Despite this, acute CSN dosage does not contribute in enhancing the glycogen replenishment in skeletal muscle during 3h recovery. We identified no significant differences in postprandial glucose and insulin area under the curve in both trials. Western blot data showed an increased muscle GLUT4 expression, but no significant response of p-Akt/Akt ratio with CSN during post-exercise recovery. CONCLUSION: Our findings conclude that acute CSN intake could change energy reliance on fat oxidation but is unable to enhance muscle glycogen resynthesis during post-exercise recovery. Thus, ergogenic properties of CSN in relevance to muscle glycogen restoration following exercise needs to be further investigated in young adults.
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Ejercicio Físico , Glucógeno , Adulto , Glucemia , Estudios Cruzados , Suplementos Dietéticos , Transportador de Glucosa de Tipo 4 , Glucógeno/metabolismo , Humanos , Insulina , Masculino , Músculo Esquelético/metabolismo , Adulto JovenRESUMEN
The aim of this study was to examine the effects of Eleutherococcus senticosus (ES) supplementation on endurance capacity, cardiovascular functions and metabolism of recreationally trained males for 8 weeks. Nine recreationally trained males in college consumed 800 mg/d of ES or starch placebo (P) for 8 weeks according to a double-blind, randomized, placebo controlled and crossover design with a washout period of 4 weeks between the cycling trials. Subjects cycled at 75% VO2 peak until exhaustion. The examined physiological variables included endurance time, maximal heart rate during exhaustion exercise, VO2, rating of perceived exertion and respiratory exchange ratio. The biochemical variables including the plasma free fatty acid (FFA) and glucose were measured at rest, 15 min, 30 min and exhaustion. The major finding of this study was the VO2 peak of the subjects elevated 12% (P < 0.05), endurance time improved 23% (P < 0.05) and the highest heart rate increased 4% (P < 0.05) significantly. The second finding was at 30 min of 75% VO2 peak cycling, the production of plasma FFA was increased and the glucose level was decreased both significantly (P < 0.05) over 8-week ES supplementation. This is the first well-conducted study that shows that 8-week ES supplementation enhances endurance capacity, elevates cardiovascular functions and alters the metabolism for sparing glycogen in recreationally trained males.
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Suplementos Dietéticos , Medicamentos Herbarios Chinos/farmacología , Eleutherococcus , Metabolismo/efectos de los fármacos , Resistencia Física/efectos de los fármacos , Adolescente , Glucemia/metabolismo , Estudios Cruzados , Método Doble Ciego , Medicamentos Herbarios Chinos/administración & dosificación , Ácidos Grasos no Esterificados/sangre , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Metabolismo/fisiología , Consumo de Oxígeno/efectos de los fármacos , Consumo de Oxígeno/fisiología , Resistencia Física/fisiología , Factores de Tiempo , Adulto JovenRESUMEN
The present study aimed to investigate the effect of oral resveratrol supplementation on the key molecular gene expressions involved in mitochondria biogenesis and glycogen resynthesis in human skeletal muscle. Nine young male athletes participated in the single-blind and crossover designed study. All subjects completed a 4-day resveratrol and placebo supplement in a randomized order while performing a single bout of cycling exercise. Immediately after the exercise challenge, the subjects consumed a carbohydrate (CHO) meal (2 g CHO/Kg body mass) with either resveratrol or placebo capsules. Biopsied muscle samples, blood samples and expired gas samples were obtained at 0 h and 3 h after exercise. The muscle samples were measured for gene transcription factor expression by real-time PCR for glucose uptake and mitochondria biogenesis. Plasma glucose, insulin, glycerol, non-esterified fatty acid concentrations and respiratory exchange ratio were analyzed during post-exercise recovery periods. The results showed that the muscle glycogen concentrations were higher at 3 h than at 0 h; however, there were no difference between resveratrol trial and placebo trial. There were no significantly different concentrations in plasma parameters between the two trials. Similarly, no measured gene expressions were significant between the two trials. The evidence concluded that the 4-day oral resveratrol supplementation did not improve post-exercise muscle glycogen resynthesis and related glucose uptake and mitochondrial biosynthesis gene expression in men.
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Suplementos Dietéticos , Ejercicio Físico/fisiología , Glucógeno/metabolismo , Mitocondrias/metabolismo , Músculo Esquelético/metabolismo , Resveratrol/farmacología , Glucemia/metabolismo , Metabolismo Energético , Humanos , Insulina/sangre , Masculino , ARN Mensajero , Método Simple Ciego , Adulto JovenRESUMEN
This randomized, double-blind, clinical trial was designed to compare the endurance capacity (ergogenic property) in healthy athletes after consumption of apple cider vinegar (ACV) and a commercial sports drink (CSD) before and during endurance exercise. Fourteen healthy participants were enrolled in this trial and were divided into two groups as ACV and CSD with seven participants in each. Participants were requested to consume 500â¯mL of either commercial ACV or CSD 1â¯h before endurance exercise (bicycle ergometer). Blood samples were collected at baseline, 0, 20, 40, 60â¯min until exhaustion to assess glucose, lactate, ammonia and non-esterified fatty acids (NEFA). Respiratory exchange rate (RER) score was measured every 15â¯min and the heart rate (HR) was measured every 5â¯min. The outcome of the present trial clearly showed that no significant differences were observed between ACV and CSD except in the blood level of ammonia (only at exhaustion time). Thus, these results show that ACV and the CSD both possessing the ergogenic property, enhanced blood glucose, NEFA, and suppress the production of lactate as well as maintains normal RER score, and HR throughout the endurance exercise. Overall this trial showcases that ACV did not significantly improve the ergogenic activity over the CSD.
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Aerobic exercise induces oxidative stress and DNA damage, nevertheless, lowers cancer incidence. It remains unclear how genetic stability is maintained under this condition. Here, we examined the dynamic change of the tumor suppressor p16INK4a in cells of skeletal muscle among young men following 60-min of aerobic cycling at 70% maximal oxygen consumption (VÌO2max). Rg1 (5 mg, an immunostimulant ginsenoside) and placebo (PLA) were supplemented 1 h before exercise. Data from serial muscle biopsies shows unchanged p16INK4a+ cells after exercise followed by a considerable increase (+21-fold) in vastus lateralis muscle 3 h later. This increase was due to the accumulation of endothelial progenitor cells (p16INK4a+/CD34+) surrounding myofibers and other infiltrated nucleated cells (p16INK4a+/CD34-) in necrotic myofibers. During the Rg1 trial, acute increases of p16INK4a+ cells in the muscle occurred immediately after exercise (+3-fold) and reversed near baseline 3 h later. Rg1 also lowered IL-10 mRNA relative to PLA 3 h after exercise. Post-exercise increases in VEGF mRNA and CD163+ macrophages were similar for PLA and Rg1 trials. Conclusion: The marked increases in p16INK4a protein expression of endothelial progenitor cells in skeletal muscle implicates a protective mechanism for maintaining genetic stability against aerobic exercise. Rg1 accelerates resolution of the exercise-induced stress response.
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Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Células Progenitoras Endoteliales/metabolismo , Ejercicio Físico , Contracción Muscular , Músculo Cuádriceps/metabolismo , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Ciclismo , Estudios Cruzados , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Daño del ADN , Regulación hacia Abajo , Células Progenitoras Endoteliales/efectos de los fármacos , Células Progenitoras Endoteliales/patología , Ginsenósidos/administración & dosificación , Humanos , Interleucina-10/genética , Interleucina-10/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Necrosis , Estrés Oxidativo , Consumo de Oxígeno , Músculo Cuádriceps/efectos de los fármacos , Músculo Cuádriceps/patología , Receptores de Superficie Celular/metabolismo , Factores de Tiempo , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Adulto JovenRESUMEN
We investigated the effect of chronic seaweed (Gracilaria asiatica) supplementation on maximal carrying capacity, muscle mass, and oxidative stress in rats following high-intensity resistance exercise (RE). Forty Sprague-Daley rats were equally categorized into control, exercise, seaweed, and exercise plus seaweed (ES) groups. Rats in respective groups performed RE (once per 2 days) or received seaweed (250 mg/kg bodyweight, orally) for 10 weeks. Results showed that seaweed consumption in combination with RE significantly (p < 0.05) increased maximal weight carrying capacity compared to RE alone. FHL muscle mass was significantly higher in both exercise and ES groups. Notably, high-intensity RE-induced lipid peroxidation, as evidenced by elevated thiobarbituric acid reactive substances (TBARS) in muscle, was substantially diminished (p < 0.05) by seaweed treatment. This antioxidative effect of seaweed was further represented by augmented superoxide dismutase activity and glutathione levels in seaweed groups. We noticed increased insulin concentrations and HOMA-IR, while the fasting blood glucose levels remained stable in seaweed and ES groups. Our findings conclude that seaweed in combination with RE enhanced maximal carrying strength and attenuated oxidative stress through improved antioxidant capacity. Seaweed could be a potential nutritional supplement to boost performance and to prevent exercise-induced muscle damage.
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BACKGROUND: Ginsenoside Rg1 has been shown to clear senescence-associated beta-galactosidase (SA-ß-gal) in cultured cells. It remains unknown whether Rg1 can influence SA-ß-gal in exercising human skeletal muscle. METHODS: To examine SA-ß-gal change, 12 young men (age 21 ± 0.2 years) were enrolled in a randomized double-blind placebo controlled crossover study, under two occasions: placebo (PLA) and Rg1 (5 mg) supplementations 1 h prior to a high-intensity cycling (70% VO2max). Muscle samples were collected by multiple biopsies before and after cycling exercise (0 h and 3 h). To avoid potential effect of muscle biopsy on performance assessment, cycling time to exhaustion test (80% VO2max) was conducted on another 12 participants (age 23 ± 0.5 years) with the same experimental design. RESULTS: No changes of SA-ß-gal were observed after cycling in the PLA trial. On the contrary, nine of the 12 participants showed complete elimination of SA-ß-gal in exercised muscle after cycling in the Rg1 trial (p < 0.05). Increases in apoptotic DNA fragmentation (PLA: +87% vs. Rg1: +133%, p < 0.05) and CD68+ (PLA: +78% vs. Rg1: +121%, p = 0.17) occurred immediately after cycling in both trials. During the 3-h recovery, reverses in apoptotic nuclei content (PLA: +5% vs. Rg1: -32%, p < 0.01) and increases in inducible nitrate oxide synthase and interleukin 6 mRNA levels of exercised muscle were observed only in the Rg1 trial (p < 0.01). CONCLUSION: Rg1 supplementation effectively eliminates senescent cells in exercising human skeletal muscle and improves high-intensity endurance performance.
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We previously found that the exercise-induced elevation in GLUT4 mRNA of rat muscle can be rapidly down-regulated when glucose is given immediately following exercise. The purpose of this study was to determine the effect of postexercise carbohydrate diet on GLUT4 and hexokinase (HK) II mRNA levels in the human skeletal muscle. Eight untrained male subjects (age, 20.7+/-3.1 years) exercised for 60 min on a cycle ergometer at a 70-75% maximal oxygen consumption. The postexercise dietary treatment was performed in a crossover design. Immediately after the exercise, a diet with 70% carbohydrate content (1 g per kilogram of body weight; 356+/-19.8 kcal) was given to half of the subjects (eaten in 10 min) followed by a 3-h recovery, while the control subjects remained unfed for 3 h. Biopsies were performed on the deep portion of the vastus lateralis muscle of all subjects immediately after the exercise and 3 h after the carbohydrate ingestion. Blood glucose and serum insulin concentrations were measured every 30 min for 3 h. At the end of the 3-h recovery, blood glucose and serum insulin levels were not different from control levels, indicating that the oral carbohydrate was mostly disposed in the body within 3 h. In addition, GLUT4 and HK II mRNA levels were significantly lowered in the exercised human skeletal muscle in subjects receiving the carbohydrate diet. In conclusion, the present study demonstrates that GLUT4 mRNA and HK II mRNA in the exercised human skeletal muscle were significantly lowered by a high-carbohydrate diet.
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Carbohidratos de la Dieta/farmacología , Ejercicio Físico/fisiología , Regulación de la Expresión Génica/efectos de los fármacos , Glucosa/metabolismo , Proteínas de Transporte de Monosacáridos/biosíntesis , Proteínas Musculares/biosíntesis , Músculo Esquelético/metabolismo , Adolescente , Adulto , Glucemia/metabolismo , Regulación hacia Abajo , Transportador de Glucosa de Tipo 4 , Hexoquinasa/biosíntesis , Humanos , Masculino , Músculo Esquelético/efectos de los fármacosRESUMEN
UNLABELLED: The purpose of the study was to determine the effect of ginseng-based steroid Rg1 on TNF-alpha and IL-10 gene expression in human skeletal muscle against exercise challenge, as well as on its ergogenic outcomes. Randomized double-blind placebo-controlled crossover trials were performed, separated by a 4-week washout. Healthy young men were randomized into two groups and received capsule containing either 5 mg of Rg1 or Placebo one night and one hour before exercise. Muscle biopsies were conducted at baseline, immediately and 3 h after a standardized 60-min cycle ergometer exercise. While treatment differences in glycogen depletion rate of biopsied quadriceps muscle during exercise did not reach statistical significance, Rg1 supplementations enhanced post-exercise glycogen replenishment and increased citrate synthase activity in the skeletal muscle 3 h after exercise, concurrent with improved meal tolerance during recovery (P<0.05). Rg1 suppressed the exercise-induced increases in thiobarbituric acids reactive substance (TBARS) and reversed the increased TNF-alpha and decreased IL-10 mRNA of quadriceps muscle against the exercise challenge. PGC-1 alpha and GLUT4 mRNAs of exercised muscle were not affected by Rg1. Maximal aerobic capacity (VO2max) was not changed by Rg1. However, cycling time to exhaustion at 80% VO2max increased significantly by ~20% (P<0.05). CONCLUSION: Our result suggests that Rg1 is an ergogenic component of ginseng, which can minimize unwanted lipid peroxidation of exercised human skeletal muscle, and attenuate pro-inflammatory shift under exercise challenge.
Asunto(s)
Suplementos Dietéticos , Ejercicio Físico , Ginsenósidos/farmacología , Músculo Esquelético/efectos de los fármacos , Panax/química , Sustancias para Mejorar el Rendimiento/farmacología , Adulto , Método Doble Ciego , Ginsenósidos/química , Ginsenósidos/aislamiento & purificación , Transportador de Glucosa de Tipo 4/metabolismo , Glucógeno/metabolismo , Humanos , Interleucina-10/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Músculo Esquelético/metabolismo , Sustancias para Mejorar el Rendimiento/química , Sustancias para Mejorar el Rendimiento/aislamiento & purificación , Resistencia Física/efectos de los fármacos , ARN Mensajero/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Toona sinensis is one of the most popular vegetarian cuisines in Taiwan and it has been shown to induce apoptosis in cultured human premyelocytic leukemia (HL-60) cells. In the present study, we examined the effects of T. sinensis leaf extracts (TS extracts) on tumor regression using in vitro cell culture and an in vivo athymic nude mice model. We found that TS extracts (10-75 µg/mL) arrested HL-60 cells at the G1-S transition phase through the reductions of Cyclin D1, CDK4, Cyclin E, CDK2, and Cyclin A, and induction of CDK inhibitor p27KIP levels. Furthermore, VEGF expression and release was significantly inhibited by TS extracts. Notably, TS extracts treatment was effective in terms of delaying tumor incidence in the nude mice inoculated with HL-60 cells as well as reducing the tumor burden. Histological analysis confirmed that TS extracts significantly modulated tumor progression in xenograft tumor. Furthermore, a similar pattern of results were observed from gallic acid (5 and 10 µg/mL), a major compound in TS, caused G1 arrest through regulations of cell-cycle regulatory proteins. Our data suggest that T. sinensis exerts antiproliferative effects on HL-60 cells in vitro and in vivo due mainly to the presence of gallic acid.
Asunto(s)
Ácido Gálico/farmacología , Meliaceae/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Animales , Ciclo Celular/efectos de los fármacos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Femenino , Ácido Gálico/química , Células HL-60 , Humanos , Masculino , Ratones , Ratones Desnudos , Neoplasias Experimentales/tratamiento farmacológico , Extractos Vegetales/química , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Athletes frequently adjust their training volume in line with their athletic competition schedule, onset of sport injury, and retirement. Whether maintenance of partial training activity during the detraining period can preserve optimal body composition and insulin sensitivity is currently unknown. Sixteen elite kayak athletes (mean VO2max: 58.5 ml.kg(-1).min(-1), s = 1.77) were randomly assigned to a totally detrained group (age: 20.8 years, s = 0.7; body mass index: 23.74, s = 0.54) or partially detrained group (age: 21.8 years, s = 0.7; body mass index: 23.20, s = 1.02), whereby totally detrained participants terminated their training routine completely and the partially detrained participants preserved approximately 50% of their previous training duration with equivalent intensity for one month. Body mass, waist circumference, oral glucose tolerance test, insulin, leptin, cortisol, and testosterone were measured during the trained state and after detraining. Waist circumferences for both the partially detrained and totally detrained groups were significantly elevated after detraining, with no group difference. However, body mass was reduced in both groups. Significant elevations in the area under the curve for insulin and fasted leptin with detraining were observed. These changes were greater in the totally detrained participants. In conclusion, the present results show that maintaining partial training activity cannot prevent an increase in waist circumference. During the detraining period, the magnitude of increase in plasma insulin and leptin concentrations was regulated in an activity-dependent manner.