Inhibition of taurine transport by high concentration of glucose in cultured rat cardiomyocytes

Metabolism. 2003 Jul;52(7):827-33. doi: 10.1016/s0026-0495(03)00067-2.

Abstract

Cultured rat cardiomyocytes were treated with 10, 20, and 30 mmol/L glucose and 30 mmol/L glucose plus protein kinase C (PKC) inhibitor, Chelerythrine. In the 20 and 30 mmol/L glucose-treated cells, taurine contents reduced by 15% and 27% (P<.05), respectively, taurine transporter (TAUT) mRNA levels reduced by 47% and 64% (P<.05), respectively, and cysteine sulfinate decarboxylase (CSD) mRNA reduced slightly, but not significantly. Time-dependent taurine uptakes reduced in the 10, 20, and 30 mmol/L glucose-treated cells, and time-dependent taurine release reduced in the 30 mmol/L glucose-treated cells. The Vmax of taurine transport decreased by 18%, 30%, and 35% (P<.05) in the 10, 20, and 30 mmol/L glucose-treated cells, respectively, while Km of taurine transport remained unchanged. When PKC inhibitor, Chelerythrine, combined with 30 mmol/L glucose was treated with the cells, the lowered taurine content, taurine uptake, taurine release, and Vmax of taurine transport caused by 30 mmol/L glucose were eliminated. These results demonstrate that high glucose considerably and specifically decreases intracellular taurine content, taurine transport activity, and TAUT mRNA, possibly through PKC-mediated transcriptional and posttranslational pathways.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaloids
  • Animals
  • Benzophenanthridines
  • Biological Transport / drug effects
  • Carboxy-Lyases / genetics
  • Carrier Proteins / genetics
  • Cells, Cultured
  • Enzyme Inhibitors / pharmacology
  • Glucose / pharmacology*
  • Kinetics
  • Membrane Glycoproteins / genetics
  • Membrane Transport Proteins*
  • Myocytes, Cardiac / drug effects
  • Myocytes, Cardiac / metabolism*
  • Phenanthridines / pharmacology
  • Protein Kinase C / antagonists & inhibitors
  • RNA, Messenger / analysis
  • Rats
  • Rats, Wistar
  • Reverse Transcriptase Polymerase Chain Reaction
  • Taurine / metabolism*

Substances

  • Alkaloids
  • Benzophenanthridines
  • Carrier Proteins
  • Enzyme Inhibitors
  • Membrane Glycoproteins
  • Membrane Transport Proteins
  • Phenanthridines
  • RNA, Messenger
  • taurine transporter
  • Taurine
  • chelerythrine
  • Protein Kinase C
  • Carboxy-Lyases
  • sulfoalanine decarboxylase
  • Glucose