Ribose administration during exercise: Effects on substrates and products of energy metabolism in healthy subjects and a patient with myoadenylate deaminase deficiency

Abstract

Nine healthy men and a patient with myoadenylate deaminase deficiency were exercised on a bicycle ergometer (30 minutes, 125 Watts) with and without oral ribose administration at a dose of 2 g every 5 minutes of exercise. Plasma or serum levels of glucose, free fatty acids, lactate, ammonia and hypoxanthine and the urinary hypoxanthine excretion were determined. After 30 minutes of exercise without ribose intake the healthy subjects showed significant increases in plasma lactate (p less than 0.05), ammonia (p less than 0.01) and hypoxanthine (p less than 0.05) concentrations and a decrease in serum glucose concentration (p less than 0.05). When ribose was administered, the plasma lactate concentration increased significantly higher (p less than 0.05) and the increase in plasma hypoxanthine concentration was no longer significant. The patient showed the same pattern of changes in serum or plasma concentrations with exercise with the exception of hypoxanthine in plasma which increased higher when ribose was administered.

Ergometer exercise in myoadenylate deaminase deficient patients

“…In the control subjects, the plasma lactate level increased within the first 15rain of exercise to a mean value of 3.5mmol/1 (data from [4]). Only one subject reached plasma lactate levels above 6 mmol/1.…”

“…Three male patients with MAD deficiency aged 60 (number 1), 22 (number 2), and 44 (number 3) years took part in this study (data on patient I were previously published in [4]). These patients were selected from a group of ten patients based on their relatively high muscular performance.…”

“…Immediately prior to and after 15 and 30 min of exercise, blood samples were taken from an antecubital vein. After exercise, the subjects rested on the couch for another 3.5 h. In the experiment with patient i and a control subject, the urine was collected 24 h prior to exercise and for another 5 h after beginning exercise [4].…”

“…Student's t test for unpaired observations was used to calculate the significance of differences between patients and control subjects (data from [4]). …”

Megacell phenotype and its relation to metabolic alterations in transketolase deficient strain of Bacillus pumilus

“…D-Ribose also finds applications in treatment of myocardiac ischemia and certain rare genetic disorders (Gross et al, 1991;Zimmer, 1992;Zimmer et al, 1984). Methods based on chemical or chemo-enzymatic synthesis or fermentation process have been reported for D-ribose production (Bredereck and Rothe, 1938;DeWulf et al, 1997a;Gehrke and Aichner, 1927).…”