A high glucose concentration stimulates the expression of monocyte chemotactic peptide 1 in human mesangial cells.
The mechanism of glomerular infiltration of monocytes remains unknown in diabetic nephropathy. We examined the effect of a high glucose concentration on monocyte chemotactic peptide 1 (MCP-1) expression in human mesangial cells (MCs) by using enzyme-linked immunosorbent assay and reverse transcription coupled with polymerase chain reaction (PCR). More than a 50% increase in the MCP-1 protein production was observed in MCs cultured in high-glucose medium (450 mg/dl) as compared to normal glucose (100 mg/dl; 1,496 +/- 75 vs. 966 +/- 15 pg/ml after 24 h, 1,910 +/- 93 vs. 1,250 +/- 55 pg/ml after 48 h). Semiquantitative PCR showed that phorbol myristate acetate (100 nM) increased the ratio of PCR products for MCP-1 to housekeeping gene glyceraldehyde-3-phosphate dehydrogenase on densitometric results at 24 h by 2.7-fold, which was prevented by calphostin C (200 nM) pretreatment. High glucose increased the ratio by 3-fold as compared to normal glucose at 24 h (0.72 +/- 0.11 vs. 0.24 +/- 0.01). This was also suppressed by calphostin C pretreatment. These findings demonstrate that high glucose can directly increase MCP-1 expression in MCs, which may contribute to monocyte infiltration in diabetic nephropathy, and this is regulated by protein kinase C.
Ihm
C G
CG
Department of Internal Medicine, College of Medicine, Kyung Hee University, Seoul, Korea.
Park
J K
JK
Hong
S P
SP
Lee
T W
TW
Cho
B S
BS
Kim
M J
MJ
Cha
D R
DR
Ha
H
H
D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000378:metabolism*; D003929:Diabetic Neuropathies / Q000503:physiopathology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects*; D005920:Glomerular Mesangium / Q000378:metabolism*; D005947:Glucose / Q000494:pharmacology*; D006801:Humans; D009000:Monocytes / Q000378:metabolism*; D009281:Naphthalenes / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D012333:RNA, Messenger / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D018932:Chemokine CCL2; D004791:Enzyme Inhibitors; D009281:Naphthalenes; D012333:RNA, Messenger; D011493:Protein Kinase C; C058819:calphostin C; D005947:Glucose; D013755:Tetradecanoylphorbol Acetate