BACKGROUND: Interleukin (IL)-6, cyclooxygenase (COX)-2, and monocyte chemoattractant protein (MCP)-1 contribute to renal injury. The promoter regions of these genes contain CCAAT/enhancer-binding protein (C/EBP)-binding sites. In this study, we investigated the role of C/EBP-delta in mesangial cells (MCs). METHODS: In an in vivo study, anti-Thy 1.1 glomerulonephritis rats were generated and C/EBP-delta, IL-6, COX-2, and MCP-1 expressions were assessed by immunohistochemistry. In an in vitro study, cultured MCs were transfected with non-silencing (NS) short interfering RNA (siRNA) or C/EBP-delta siRNA. Subsequently, after stimulation with IL-1beta, C/EBP-delta, IL-6, COX-2, and MCP-1 mRNA expression levels were evaluated using real-time polymerase chain reaction (PCR). IL-6 concentration in the culture medium was determined by enzyme-linked immunosorbent assay. In addition, cell proliferative activity against IL-1beta or platelet-derived growth factor-BB was assessed by bromodeoxyuridine incorporation. RESULTS: In the in vivo study, C/EBP-delta, IL-6, COX-2, and MCP-1 were expressed in the mesangial region of anti-Thy 1.1 glomerulonephritis rats on day 1. In the in vitro study, IL-1beta increased C/EBP-delta mRNA levels in NS siRNA-transfected MCs (7.3-fold), but no increase was evident in C/EBP-delta siRNA-transfected MCs. IL-6, COX-2, and MCP-1 mRNA levels in C/EBP-delta siRNA-transfected MCs were all lower than those in NS siRNA-transfected MCs (decreases of 57.7%, 85.7%, and 69.3%, respectively). The IL-6 concentration in the culture medium from C/EBP-delta siRNA transfected MCs (7.37 +/- 4.3 pg/ml) was also lower than that in the culture medium from NS siRNA-transfected MCs (25.2 +/- 3.4 pg/ml). Cell proliferative activity in C/EBP-delta siRNA-transfected MCs was lower than that in NS siRNA transfected MCs. CONCLUSIONS: C/EBP-delta was induced in the mesangial region during the early stages of anti-Thy1.1 glomerulonephritis. C/EBP-delta contributes to inflammatory gene expression and MC proliferation.
BACKGROUND: Interleukin (IL)-6, cyclooxygenase (COX)-2, and monocyte chemoattractant protein (MCP)-1 contribute to renal injury. The promoter regions of these genes contain CCAAT/enhancer-binding protein (C/EBP)-binding sites. In this study, we investigated the role of C/EBP-delta in mesangial cells (MCs). METHODS: In an in vivo study, anti-Thy 1.1 glomerulonephritisrats were generated and C/EBP-delta, IL-6, COX-2, and MCP-1 expressions were assessed by immunohistochemistry. In an in vitro study, cultured MCs were transfected with non-silencing (NS) short interfering RNA (siRNA) or C/EBP-delta siRNA. Subsequently, after stimulation with IL-1beta, C/EBP-delta, IL-6, COX-2, and MCP-1 mRNA expression levels were evaluated using real-time polymerase chain reaction (PCR). IL-6 concentration in the culture medium was determined by enzyme-linked immunosorbent assay. In addition, cell proliferative activity against IL-1beta or platelet-derived growth factor-BB was assessed by bromodeoxyuridine incorporation. RESULTS: In the in vivo study, C/EBP-delta, IL-6, COX-2, and MCP-1 were expressed in the mesangial region of anti-Thy 1.1 glomerulonephritisrats on day 1. In the in vitro study, IL-1beta increased C/EBP-delta mRNA levels in NS siRNA-transfected MCs (7.3-fold), but no increase was evident in C/EBP-delta siRNA-transfected MCs. IL-6, COX-2, and MCP-1 mRNA levels in C/EBP-delta siRNA-transfected MCs were all lower than those in NS siRNA-transfected MCs (decreases of 57.7%, 85.7%, and 69.3%, respectively). The IL-6 concentration in the culture medium from C/EBP-delta siRNA transfected MCs (7.37 +/- 4.3 pg/ml) was also lower than that in the culture medium from NS siRNA-transfected MCs (25.2 +/- 3.4 pg/ml). Cell proliferative activity in C/EBP-delta siRNA-transfected MCs was lower than that in NS siRNA transfected MCs. CONCLUSIONS:C/EBP-delta was induced in the mesangial region during the early stages of anti-Thy1.1 glomerulonephritis. C/EBP-delta contributes to inflammatory gene expression and MC proliferation.
Authors: Y Horii; A Muraguchi; M Iwano; T Matsuda; T Hirayama; H Yamada; Y Fujii; K Dohi; H Ishikawa; Y Ohmoto Journal: J Immunol Date: 1989-12-15 Impact factor: 5.422