Nuclear factor-κB activation is involved in MCP-1 expression in human mesangial cells induced by Ox-LDL

AIM: To investigate the role of nuclear factor-κB (NF-κB) in the expression of monocyte chemoatractant protein-1 (MCP-1) in human mesangial cells (HMCs) induced by oxidized low-density lipoprotein (Ox-LDL). METHODS: HMCs were used as target cells. Inhibitory κBα (IκBα) and MCP-1 protein level was measured by cell ELISA. Activities of transcriptional factors NF-κB were determined by electrophoresis mobility shift assay (EMSA). Immunohistochemistry was used to detect the translocation of Rel p65. RESULTS: NF-κB DNA-binding activation in MCs was observed when 10-100 mg/L Ox-LDL was added to the medium, and 50 mg/L Ox-LDL caused the strongest effect (8.50±1.14, P0.01 vs control; P0.05 vs 10, 25 and 100 mg/L Ox-LDL). The most optimal stimulation time was 60 min (11.0±2.11, P0.01 vs control; P0.05 vs 30 min or 240 min). IκBα protein level in MC dropped down most obviously after 60 min incubation with 50 mg/L Ox-LDL (0.050±0.006, n=5, P0.01 vs control), while MCP-1 expression level was the highest (0.331±0.016, n=5, P0.01 vs control). The translocation of Rel p65 from cytoplasm to nucleus was detected too. NF-κB inhibitor pyrroledithiocarbomate (PDTC) could inhibit these effects induced by Ox-LDL. CONCLUSION: Activation of NF-κB regulate the expression of MCP-1 in HMCs induced by Ox-LDL.