Energy metabolism in hypoxic astrocytes : protective mechanism of fructose-1,6-bisphosphate

• Published in: Neurochemical research 1995-07, Vol.20 (7), p.785-792
• Main Authors: KELLEHER, J. A, CHAN, P. H, CHAN, T. Y. Y, GREGORY, G. A
• Format: Article
• Language: English
• Subjects: Animals; Animals, Newborn; Astrocytes - cytology; Astrocytes - drug effects; Astrocytes - metabolism; Biochemistry and metabolism; Biological and medical sciences; Carbon Dioxide - analysis; Cell Hypoxia; Cells, Cultured; Central nervous system; Cerebral Cortex - cytology; Cerebral Cortex - metabolism; Energy Metabolism - drug effects; Fructosediphosphates - metabolism; Fructosediphosphates - pharmacology; Fundamental and applied biological sciences. Psychology; Glucose - metabolism; Glycolysis - drug effects; Iodoacetates - pharmacology; Iodoacetic Acid; Kinetics; L-Lactate Dehydrogenase - analysis; Neuroprotective Agents - pharmacology; Pentose Phosphate Pathway - drug effects; Potassium Cyanide - pharmacology; Rats; Rats, Sprague-Dawley; Vertebrates: nervous system and sense organs
• ISSN: 0364-3190; 1573-6903
• DOI: 10.1007/bf00969690

The protective effects of fructose-1,6-biphosphate (FBP) during hypoxia/ischemia are thought to result from uptake and utilization of FBP as a substrate for glycolysis or from stimulation of glucose metabolism. To test these hypotheses, we measured CO2 and lactate production from [6-14C]glucose, [1-14C]glucose, and [U-14C]FBP in normoxic and hypoxic cultured astrocytes with and without FBP present. FBP had little effect on CO2 production by glycolysis, but increased CO2 production by the pentose phosphate pathway. Labeled FBP produced very small amounts of CO2. Lactate production from [1-, and 6-14C]glucose increased similarly during hypoxic hypoxia; the increase was independent of added FBP. Labeled lactate from [U-14C]FBP was minimal. We conclude that exogenous FBP is not used by astrocytes as a substrate for glycolysis and that FBP alters glucose metabolism.