Multisite control of the Crabtree effect in ascites hepatoma cells

Eur J Biochem. 2001 Apr;268(8):2512-9. doi: 10.1046/j.1432-1327.2001.02140.x.

Abstract

AS-30D hepatoma cells, a highly oxidative and fast-growing tumor line, showed glucose-induced and fructose-induced inhibition of oxidative phosphorylation (the Crabtree effect) of 54% and 34%, respectively. To advance the understanding of the underlying mechanism of this process, the effect of 5 mM glucose or 10 mM fructose on the intracellular concentration of several metabolites was determined. The addition of glucose or fructose lowered intracellular Pi (40%), and ATP (53%) concentrations, and decreased cytosolic pH (from 7.2 to 6.8). Glucose and fructose increased the content of AMP (30%), glucose 6-phosphate, fructose 6-phosphate and fructose 1,6-bisphosphate (15, 13 and 50 times, respectively). The cytosolic concentrations of Ca2+ and Mg2+ were not modified. The addition of galactose or glycerol did not modify the concentrations of the metabolites. Mitochondria isolated from AS-30D cells, incubated in media with low Pi (0.6 mM) at pH 6.8, exhibited a 40% inhibition of oxidative phosphorylation. The data suggest that the Crabtree effect is the result of several small metabolic changes promoted by addition of exogenous glucose or fructose.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Monophosphate / metabolism
  • Adenosine Triphosphate / metabolism
  • Animals
  • Ascites / metabolism*
  • Calcium / metabolism
  • Carcinoma, Hepatocellular / metabolism*
  • Cytosol / metabolism
  • Female
  • Fructose / pharmacology
  • Fructosediphosphates / metabolism
  • Fructosephosphates / metabolism
  • Glucose / metabolism
  • Glucose / pharmacology
  • Glucose-6-Phosphate / metabolism
  • Hexoses / metabolism
  • Hydrogen-Ion Concentration
  • Kinetics
  • Liver Neoplasms / metabolism*
  • Magnesium / metabolism
  • Mitochondria / metabolism
  • Oxygen / metabolism
  • Oxygen Consumption
  • Phosphorylation
  • Rats
  • Rats, Wistar
  • Saccharomyces cerevisiae / metabolism
  • Tumor Cells, Cultured

Substances

  • Fructosediphosphates
  • Fructosephosphates
  • Hexoses
  • Fructose
  • Adenosine Monophosphate
  • Glucose-6-Phosphate
  • fructose-6-phosphate
  • Adenosine Triphosphate
  • Magnesium
  • Glucose
  • fructose-1,6-diphosphate
  • Oxygen
  • Calcium