Suppression Subtractive Hybridization Identifies High Glucose Levels as a Stimulus for Expression of Connective Tissue Growth Factor and Other Genes in Human Mesangial Cells

J Biol Chem. 1999 Feb 26;274(9):5830-4. doi: 10.1074/jbc.274.9.5830.

Abstract

Accumulation of mesangial matrix is a pivotal event in the pathophysiology of diabetic nephropathy. The molecular triggers for matrix production are still being defined. Here, suppression subtractive hybridization identified 15 genes differentially induced when primary human mesangial cells are exposed to high glucose (30 mM versus 5 mM) in vitro. These genes included (a) known regulators of mesangial cell activation in diabetic nephropathy (fibronectin, caldesmon, thrombospondin, and plasminogen activator inhibitor-1), (b) novel genes, and (c) known genes whose induction by high glucose has not been reported. Prominent among the latter were genes encoding cytoskeleton-associated proteins and connective tissue growth factor (CTGF), a modulator of fibroblast matrix production. In parallel experiments, elevated CTGF mRNA levels were demonstrated in glomeruli of rats with streptozotocin-induced diabetic nephropathy. Mannitol provoked less mesangial cell CTGF expression in vitro than high glucose, excluding hyperosmolality as the key stimulus. The addition of recombinant CTGF to cultured mesangial cells enhanced expression of extracellular matrix proteins. High glucose stimulated expression of transforming growth factor beta1 (TGF-beta1), and addition of TGF-beta1 to mesangial cells triggered CTGF expression. CTGF expression induced by high glucose was partially suppressed by anti-TGF-beta1 antibody and by the protein kinase C inhibitor GF 109203X. Together, these data suggest that 1) high glucose stimulates mesangial CTGF expression by TGFbeta1-dependent and protein kinase C dependent pathways, and 2) CTGF may be a mediator of TGFbeta1-driven matrix production within a diabetic milieu.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cells, Cultured
  • Cloning, Molecular
  • Connective Tissue Growth Factor
  • DNA, Complementary
  • Diabetic Nephropathies / pathology
  • Gene Expression Regulation / drug effects*
  • Glomerular Mesangium / metabolism*
  • Glomerular Mesangium / pathology
  • Glucose / pharmacology*
  • Growth Substances / genetics*
  • Humans
  • Immediate-Early Proteins*
  • Intercellular Signaling Peptides and Proteins*
  • Molecular Sequence Data
  • Nucleic Acid Hybridization
  • Protein Kinase C / metabolism
  • Rats
  • Sequence Homology, Amino Acid
  • Sequence Homology, Nucleic Acid
  • Transforming Growth Factor beta / metabolism

Substances

  • CCN2 protein, human
  • CCN2 protein, rat
  • DNA, Complementary
  • Growth Substances
  • Immediate-Early Proteins
  • Intercellular Signaling Peptides and Proteins
  • Transforming Growth Factor beta
  • Connective Tissue Growth Factor
  • Protein Kinase C
  • Glucose

Associated data

  • GENBANK/AF079531
  • GENBANK/AF110136
  • GENBANK/AF110137