Vanadate reduces sodium-dependent glucose transport and increases glycolytic activity in LLC-PK1 epithelia

J Cell Physiol. 1994 Mar;158(3):459-66. doi: 10.1002/jcp.1041580310.

Abstract

The effect of vanadate pentoxide on apical sodium-dependent glucose transport in LLC-PK1 epithelia was examined. Epithelia grown in the presence or absence of 1 microM vanadate formed confluent monolayers and exhibited no differences in DNA, protein, or ultrastructure. Vanadate-supplemented epithelia demonstrated a lower steady-state alpha-methyl-D-glucopyranoside (AMG) concentrating capacity and a twofold reduction in apical AMG uptake Jmax. This decreased AMG transport occurred as a consequence of a reduction in the number of transport carriers and was not associated with a change in the sodium electrochemical gradient. The vanadate-induced reduction in apical glucose carrier functional activity and expression was accompanied by a stimulation of intracellular glycolytic flux activity, as evidenced by increased glucose consumption, lactate production, PFK-1 activity, and intracellular ATP. There was no difference in intracellular cAMP levels between vanadate-supplemented and non-supplemented epithelia. These results demonstrate an association between stimulation of glycolytic pathway activity and an adaptive response in the form of a reduction in the function and expression of the sodium-dependent apical glucose transporter in LLC-PK1 epithelia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Animals
  • Cell Line
  • Cyclic AMP / analysis
  • Cyclic AMP / metabolism
  • Epithelial Cells
  • Epithelium / metabolism
  • Epithelium / physiology
  • Glucose / metabolism
  • Glycolysis / drug effects
  • Glycolysis / physiology*
  • Hexoses / metabolism
  • Kidney / cytology*
  • Kidney / metabolism*
  • Kidney / physiology
  • Lactates / metabolism
  • Methylglucosides / metabolism
  • Methylglucosides / pharmacokinetics
  • Monosaccharide Transport Proteins / analysis
  • Monosaccharide Transport Proteins / physiology*
  • Phlorhizin / metabolism
  • Rubidium Radioisotopes
  • Sodium-Potassium-Exchanging ATPase / metabolism
  • Sodium-Potassium-Exchanging ATPase / physiology
  • Swine
  • Vanadates / pharmacology*

Substances

  • Hexoses
  • Lactates
  • Methylglucosides
  • Monosaccharide Transport Proteins
  • Rubidium Radioisotopes
  • Vanadates
  • Adenosine Triphosphate
  • Phlorhizin
  • Cyclic AMP
  • Sodium-Potassium-Exchanging ATPase
  • Glucose