Chronic oral ascorbic acid therapy worsens skeletal muscle metabolism in patients with chronic heart failure.
Eur J Heart Fail
; 9(3): 287-91, 2007 Mar.
Article
en En
| MEDLINE
| ID: mdl-17023203
BACKGROUND: Chronic heart failure (CHF) is associated with abnormalities of skeletal muscle metabolism. This may be due to impaired oxygen delivery as a result of endothelial dysfunction. AIMS: We postulated that ascorbic acid would improve oxygen delivery to exercising muscle and improve skeletal muscle metabolism. METHODS: We studied skeletal muscle metabolism using (31)P magnetic resonance spectroscopy in 39 CHF patients. Endothelial function was assessed by changes in pulse wave velocity. Subjects were randomised to receive 4 g ascorbic acid daily for 4 weeks in a placebo-controlled double-blind study. RESULTS: Ascorbic acid significantly increased phosphocreatine utilization during exercise. In addition, glycolytic ATP synthesis increased in the ascorbic acid group (change in rate of ATP synthesis at 1 min -0.21+/-0.76 with placebo, 2.06+/-0.60 following ascorbic acid; p<0.05). Phosphocreatine and ADP recovery after exercise were not changed. The fall in pulse wave velocity during reactive hyperaemia was increased by ascorbic acid from -6.3+/-2.6% to -12.1+/-2.0% (p<0.05). CONCLUSIONS: These findings suggest that ascorbic acid increased both phosphocreatine utilization and glycolytic ATP synthesis during exercise in patients with CHF implying worsened skeletal muscle metabolism despite improvements in endothelial function.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Ácido Ascórbico
/
Endotelio Vascular
/
Músculo Esquelético
/
Insuficiencia Cardíaca
Tipo de estudio:
Clinical_trials
Límite:
Aged
/
Female
/
Humans
/
Male
/
Middle aged
País/Región como asunto:
Europa
Idioma:
En
Revista:
Eur J Heart Fail
Asunto de la revista:
CARDIOLOGIA
Año:
2007
Tipo del documento:
Article
Pais de publicación:
Reino Unido