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1.
J Int Soc Sports Nutr ; 14: 47, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29296106

RESUMO

BACKGROUND: Skeletal muscle adenosine triphosphate (ATP) levels are severely depleted during and following prolonged high intensity exercise. Recovery from these lower ATP levels can take days, which can affect performance on subsequent days of exercise. Untrained individuals often suffer the stress and consequences of acute, repeated bouts of exercise by not having the ability to perform or recovery sufficiently to exercise on subsequent days. Conversely, trained individuals may be able to recover more quickly due to their enhanced metabolic systems. D-Ribose (DR) has been shown to enhance the recovery in ATP; however, it is not known if recovery and performance can be benefitted with DR ingestion. Therefore, this study was designed to determine what influence DR might have on muscular performance, recovery, and metabolism during and following a multi-day exercise regimen. METHODS: The study was a double blind, crossover study in 26 healthy subjects compared 10 g/day of DR to 10 g/day of dextrose (DEX, control). All subjects completed 2 days of loading with either DR or DEX, followed by 3 additional days of supplementation and during these 3 days of supplementation, each subject underwent 60 min of high intensity interval exercise in separate daily sessions, which involved cycling (8 min of exercise at 60% and 2 min at 80% VO2max), followed by a 2 min power output (PO) test. Subjects were divided into two groups based on peak VO2 results, lower VO2 (LVO2) and higher peak VO2 (HVO2). RESULTS: Mean and peak PO increased significantly from day 1 to day 3 for the DR trial compared to DEX in the LVO2 group. Rate of perceived exertion (RPE) and creatine kinase (CK) were significantly lower for DR than DEX in the LVO2 group. No differences in PO, RPE, heart rate, CK, blood urea nitrogen, or glucose were found between either supplement for the HVO2 group. CONCLUSION: DR supplementation in the lower VO2 max group resulted in maintenance in exercise performance, as well as lower levels of RPE and CK. Unlike no observed benefits with DEX supplementation.


Assuntos
Trifosfato de Adenosina/metabolismo , Limiar Anaeróbio/efeitos dos fármacos , Desempenho Atlético/fisiologia , Suplementos Nutricionais , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Aptidão Física/fisiologia , Ribose/farmacologia , Adulto , Limiar Anaeróbio/fisiologia , Estudos Cross-Over , Método Duplo-Cego , Metabolismo Energético/efeitos dos fármacos , Feminino , Humanos , Masculino , Fenômenos Fisiológicos da Nutrição Esportiva
2.
J Diet Suppl ; 9(3): 178-82, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22891990

RESUMO

A healthy cellular system involves the maintenance of an intracellular metabolic balance. Reactive oxygen species (ROS) are constantly produced as a normal product of cellular metabolism; however, during situations of cellular stress, these levels can increase dramatically with the potential to cause deleterious cellular structural and/or functional consequences. There is a significant elevation in these ROS following stressful situations, such as ischemia, hypoxia, high-intensity exercise, and in many diseases. To combat these ROS, neutralizing endogenous enzymes, as well as exogenous antioxidants, can aid in minimizing their potential untoward cellular effects. Exogenous reducing antioxidant agents, such as vitamin C and/or E, play a role in addressing these formed species; however, recent research has suggested that fruit seed extracts may provide additional cellular benefits beyond their antioxidant features. Furthermore, supplemental D-ribose enhances the recovery of high-energy phosphates following stress and appears to potentially offer additional benefits by reducing radical formation. Specifically, during periods of hypoxia/ischemia, supplemental D-ribose may play an inhibitory role in the breakdown of adenine nucleotides, influencing the subsequent formation of xanthine and uric acid compounds; and thereby affecting the release of superoxide anion radicals. The combination of D-ribose with reducing antioxidants may provide a more optimal state of cellular protection during and following times of oxidative stress.


Assuntos
Nucleotídeos de Adenina/metabolismo , Antioxidantes/uso terapêutico , Citoproteção/efeitos dos fármacos , Suplementos Nutricionais , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Ribose/uso terapêutico , Antioxidantes/farmacologia , Hipóxia Celular/efeitos dos fármacos , Humanos , Ribose/farmacologia , Sementes , Superóxidos/metabolismo , Ácido Úrico/metabolismo , Xantina/metabolismo
5.
Recent Pat Cardiovasc Drug Discov ; 5(2): 138-42, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20236088

RESUMO

Cardiovascular diseases account for more deaths worldwide than any other illness. Myocardial ischemia, a common finding in cardiovascular diseases, lowers cellular energy levels, which affects a cell's integrity and function. Pre-clinical animal studies have reported lower cellular energy levels with an associated decreased function following myocardial ischemia. Recently, scientists have reported that the failing heart is energy starved and yet no pharmaceuticals have been able to address this issue with satisfactory results. Over decades, researchers have explored the use of various metabolites to replenish deficient cellular energy levels following induced ischemia with mixed results. However, D-ribose, a natural occurring carbohydrate, has demonstrated significant enhancing abilities in replenishing deficient cellular energy levels following myocardial ischemia, as well as improving depressed function in numerous animal investigations. Subsequent clinical trials have further substantiated these benefits of D-ribose in patients afflicted with ischemic cardiovascular disease and those carrying the diagnosis of congestive heart failure. The future of effective therapies for ischemic heart disease and congestive heart failure must strongly consider novel pharmaceuticals directed at replenishing cellular energy levels. Intellectual property and the represented patents in this paper emphasize the use of D-ribose for its cellular energy enhancing potential, reflected in both objective and subjective clinical improvements; therefore, substantiating its value in patients with ischemic cardiovascular diseases.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Insuficiência Cardíaca/tratamento farmacológico , Isquemia Miocárdica/tratamento farmacológico , Ribose/uso terapêutico , Trifosfato de Adenosina/análise , Animais , Ensaios Clínicos como Assunto , Suplementos Nutricionais , Avaliação Pré-Clínica de Medicamentos , Metabolismo Energético , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Isquemia Miocárdica/complicações , Isquemia Miocárdica/fisiopatologia , Miocárdio/metabolismo , Patentes como Assunto , Ribose/metabolismo
6.
J Altern Complement Med ; 16(3): 323-5, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20156124

RESUMO

BACKGROUND: Cardiomyopathy is reflected in a deterioration of heart function, increased risk of developing arrhythmias, and the potential for sudden cardiac death. The use of enhanced external counterpulsation has been recommended for treating chronic stable angina in high-risk surgical patients. Furthermore, cells require adequate levels of adenosine triphosphate for the maintenance of integrity and function. Lower myocardial levels of adenosine triphosphate are commonly found with ischemia and heart failure. d-Ribose, a natural occurring carbohydrate, enhances the regeneration of adenosine triphosphate levels and improves diastolic function following ischemia. SUBJECT: We present a patient with cardiomyopathy and marked reduced cardiac function. CONCLUSIONS: This patient underwent enhanced external counterpulsation and metabolic supplementation, including d-ribose, and achieved a significant functional improvement.


Assuntos
Cardiomiopatias/terapia , Contrapulsação/métodos , Suplementos Nutricionais , Ribose/administração & dosagem , Ubiquinona/análogos & derivados , Vitaminas/administração & dosagem , Idoso , Cardiomiopatias/prevenção & controle , Terapia Combinada , Ecocardiografia , Insuficiência Cardíaca/prevenção & controle , Humanos , Masculino , Contração Miocárdica , Qualidade de Vida , Resultado do Tratamento , Ubiquinona/administração & dosagem
7.
J Med Food ; 12(3): 690-3, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19627222

RESUMO

Oxygen free radicals are produced during stress, are unstable, and potentially interact with other cellular components or molecules. This reactivity can influence cellular function, including a prolongation in tissue recovery following exercise. We tested the effect of ribose (d-ribose), a pentose carbohydrate, in a double-blinded, crossover study on markers of free radical production during hypoxic exercise. Seven healthy volunteers cycled at their lactate threshold for 25 minutes while inhaling 16% O(2) with a subsequent 60-minute resting period at room air. Subjects ingested either placebo or 7 g of ribose in 250 mL of water before and after the exercise session. Urinary malondialdehyde (MDA) and plasma reduced glutathione levels increased significantly during placebo ingestion (0.2 +/- 0.03 nM/mg and 0.26 +/- 0.29 microM, respectively) but were lower with ribose supplementation (0.04 +/- 0.03 nM/mg and 0.38 +/- 0.29 microM, respectively; P < .05). Uric acid levels were similar between groups (ribose vs. placebo, 4.55 +/- 0.06 mg/dL vs. 4.67 +/- 0.06 mg/dL). Ribose demonstrated a beneficial trend in lower MDA and reduced glutathione levels during hypoxic stress.


Assuntos
Antioxidantes/farmacologia , Ciclismo/fisiologia , Exercício Físico/fisiologia , Glutationa/sangue , Hipóxia/tratamento farmacológico , Hipóxia/fisiopatologia , Malondialdeído/urina , Estresse Oxidativo , Ribose/fisiologia , Estudos Cross-Over , Carboidratos da Dieta/metabolismo , Suplementos Nutricionais , Método Duplo-Cego , Radicais Livres/metabolismo , Humanos , Ácido Láctico/metabolismo , Oxigênio/metabolismo , Projetos Piloto , Ribose/metabolismo
8.
Prog Cardiovasc Nurs ; 24(2): 59-60, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19523159

RESUMO

The incidence of congestive heart failure continues to escalate worldwide, taxing health care systems. Current therapies focus on clinical management. Current accepted regimens have provided some success; however, most patients show progression of their disease. Because of this failure, research continues to explore therapies directed at stabilization of their disease and hopefully to improve the downward spiral. Publications have asserted that the failing heart is energy starved. D-ribose, a naturally occurring pentose carbohydrate and a key component in the adenosine triphosphate (ATP) molecule, has demonstrated an ability to replenish ATP levels and improve diastolic dysfunction following myocardial ischemia, which has been shown to improve the clinical state of patients afflicted with congestive heart failure. D-ribose may provide the necessary metabolic substrate to benefit this energy-deficient state found in heart failure.


Assuntos
Suplementos Nutricionais , Insuficiência Cardíaca/terapia , Ribose/uso terapêutico , Trifosfato de Adenosina/biossíntese , Humanos
9.
Am J Physiol Heart Circ Physiol ; 293(3): H1869-76, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17604325

RESUMO

During ischemic heart diseases and when heart failure progresses depletion of myocardial energy stores occurs. D-Ribose (R) has been shown to improve cardiac function and energy status after ischemia. Folic acid (FA) is an essential cofactor in the formation of adenine nucleotides. Therefore, we assessed whether chronic R-FA administration during the development of hypertrophy resulted in an improved cardiac function and energy status. In Wistar rats (n = 40) compensatory right ventricular (RV) hypertrophy was induced by monocrotaline (30 mg/kg; MCT), whereas saline served as control. Both groups received a daily oral dose of either 150 mg.kg(-1).day(-1) dextrose (placebo) or R-FA (150 and 40 mg.kg(-1).day(-1), respectively). In Langendorff-perfused hearts, RV and left ventricular (LV) pressure development and collagen content as well as total RV adenine nucleotides (TAN), creatine content, and RV and LV collagen content were determined. In the control group R-FA had no effect. In the MCT-placebo group, TAN and creatine content were reduced, RV and LV diastolic pressure-volume relations were steeper, RV systolic pressures were elevated, RV and LV collagen content was increased, and RV-LV diastolic interaction was altered compared with controls. In the MCT-R-FA group, TAN, RV and LV diastolic stiffness, RV and LV collagen content, and RV-LV diastolic interaction were normalized to the values in the control group while creatine content remained depressed and RV systolic function remained elevated. In conclusion, the depression of energy status in compensated hypertrophic myocardium observed was partly prevented by chronic R-FA administration and accompanied by a preservation of diastolic function and collagen deposition.


Assuntos
Ácido Fólico/uso terapêutico , Hipertrofia Ventricular Direita/tratamento farmacológico , Hipertrofia Ventricular Direita/fisiopatologia , Função Ventricular Direita/fisiologia , Nucleotídeos de Adenina/metabolismo , Animais , Pressão Sanguínea/fisiologia , Colágeno/metabolismo , Creatina/metabolismo , Suplementos Nutricionais , Ácido Fólico/farmacologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Homocisteína/sangue , Hipertrofia Ventricular Direita/induzido quimicamente , Masculino , Monocrotalina , Contração Miocárdica/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Wistar , Função Ventricular Esquerda/efeitos dos fármacos , Função Ventricular Esquerda/fisiologia , Função Ventricular Direita/efeitos dos fármacos
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