Shuttling of intermediary metabolites, such as pyruvate, contributes to the dynamic energy and biosynthetic needs of tissues. Tracer kinetic studies offer a powerful tool to measure the metabolism of substrates like pyruvate that are simultaneously taken up from and released into the circulation by organs. However, we understood that during each circulatory passage, the entire cardiac output tr...

Introduction: Metabolic imaging with hyperpolarized [1-C]pyruvate enables the real-time in-vivo observation of metabolism [1]. The typical injected pyruvate dose is a multiple of physiological concentration levels, which may lead to saturation effects in pyruvate metabolism. Under this condition the observed conversion rates between pyruvate and its metabolic products are not only dependent on ...

Pyruvate dehydrogenase complex is associated with intact chloroplasts and mitochondria of 9-day-old Pisum sativum L. seedlings. The ratio of the mitochondrial complex to the chloroplast complex activities is about 3 to 1. Maximal rates observed for chloroplast pyruvate dehydrogenase complex activity ranged from 6 to 9 micromoles of NADH produced per milligram of chlorophyll per hour. Osmotic ru...

background: there are many reports regarding to effects of granulocyte colony-stimulating factor (g-csf) and stem cell factor (scf)alone in liver repair .but conflicting data have been reported regarding the role of growth factors such as g-csf and scf in the liver regeneration system. also, there is not such data regarding to effects of co-administration both of g-csf and scf in the liver dama...

Cells in culture are exposed to marked oxidative stress, H2O2 being one of the predominant agents. Pyruvate and other alpha-ketoacids reacted rapidly, stoichiometrically, and nonenzymatically with H2O2, and they protected cells from its cytolytic effects. All five human and murine cell types studied, both malignant and nonmalignant, released pyruvate at an initial rate of 35-60 microM/h/2.5 X 1...

Extracorporeal membrane oxygenation (ECMO) provides mechanical circulatory support for infants and children with postoperative cardiopulmonary failure. Nutritional support is mandatory during ECMO although specific actions for substrates on the heart have not been delineated. Prior work shows that enhancing pyruvate oxidation promotes successful weaning from ECMO. Accordingly, we tested the hyp...

A method is described to measure the intracellular content of pyruvate and lactate in epididymal adipose tissue of the rat. The intracellular pyruvate concentration was approx. 330M. Intracellular pyruvate contents and the rates of pyruvate output were increased when NNN'N'-tetramethyl-p-phenylenediamine was added, and decreased in the presence of alanine. Insulin addition caused an increase in...

1. In isolated pancreatic islets, pyruvate causes a shift to the left of the sigmoidal curve relating the rate of insulin release to the ambient glucose concentration. The magnitude of this effect is related to the concentration of pyruvate (5--90 mM) and, at a 30 mM concentration, is equivalent to that evoked by 2 mM-glucose. Pyruvate also enhances insulin release in the presence of fructose, ...