Korean J Nephrol.  2001 Jul;20(4):613-623.

High Glucose Induces MCP-1 Expression in Cultured Human Mesangial Cells Partly Via Tyrosine Kinase-AP-1 Pathway

• Chang SP
• Kim CS
• Kim MJ
• Kim SB
• Lee SK
• Park JS

Abstract

Infiltration of circulating monocytes into glomeruli has been implicated in the pathogenesis of glomerular injury in many human and experimental forms of glomerulonephritis. Monocyte chemoattractant protein-1(MCP-1), a potent chemokine with considerable specificity for monocytes, can be up-regulated by various cytokines and growth factors in mesangial cells. Glomerular infiltration of monocytes has been reported in diabetic nephropathy as well. However, effect of high glucose on MCP-1 expression in human mesangial cells has not been known well. We investigated the effect of high glucose on MCP-1 expression and its signal transduction pathway. Human mesangial cells were conditioned with glucose(5-60 mM) or mannitol chronically for up to 5 days. Expression of MCP-1 mRNA and protein was measured by Northern blot analysis and ELISA respectively. To examine the role of transcription factor AP-1 or NF-KB, electrophoretic mobility shift assay(EMSA) was performed. Glucose induced MCP-1 mRNA expression in a time and dose dependent manner. MCP-1 protein in cell culture supernant was also increased. Equivalent concentrations of mannitol had no significant effect. EMSA revealed that glucose increased the AP-1 binding activity in a time and dose dependent manner but not NF-B. Inhibitor of AP-1, curcumin(7.5- 15 muM) dose dependently suppressed the induction of MCP-1 mRNA by high glucose. Tyrosine kinase inhibitors such as genistein(12.5-50 muM) and herbimycin A(0.1-1 muM) inhibited the high glucose-induced MCP-1 mRNA expression in a dose dependent manner and also suppressed the high glucose-induced AP-1 binding activity. In summary, high glucose induces mesangial MCP-1 expression partly via tyrosine kinase-AP-1 pathway.

Keyword

Glucose; MCP-1; AP-1; Protein tyrosine kinase; Mesangial cells

MeSH Terms

Blotting, Northern
Cell Culture Techniques
Cytokines
Diabetic Nephropathies
Enzyme-Linked Immunosorbent Assay
Glomerulonephritis
Glucose*
Humans*
Intercellular Signaling Peptides and Proteins
Mannitol
Mesangial Cells*
Monocytes
NF-kappa B
Protein-Tyrosine Kinases
RNA, Messenger
Sensitivity and Specificity
Signal Transduction
Transcription Factor AP-1
Tyrosine*
Cytokines
Glucose
Intercellular Signaling Peptides and Proteins
Mannitol
NF-kappa B
Protein-Tyrosine Kinases
RNA, Messenger
Transcription Factor AP-1
Tyrosine