RESUMO
Objective :To explore influence of oxidized low density lipoprotein (ox-LDL ) on migration function of THP-1 macrophages ,expression of microRNA 21 (miR-21) and mitogen-activated protein kinase (MAPK) path-way.Methods :Phorbol myristate acetate (PMA) of 160nmol/L was used to induce THP-1 cells to differentiate into macrophages.According to application of ox-LDL treatment and liposomes-mediated miR-21 inhibitor transfecting THP-1 macrophages (transfection for short) or not ,THP-1 macrophages were divided into blank control group (re-ceived neither ox-LDL treatment nor transfection ) ,ox-LDL group (received 50mg/L ox-LDL treatment without transfection) ,miR-21 inhibitor group (received 50mg/L ox-LDL treatment after transfection ) and miR-21 inhibitor negative-control group (received 50mg/L ox-LDL treatment after negative-control transfection ).THP-1 macro-phage migration number was measured by transwell method ,miR-21 expression was measured by real-time quantita-tive PCR ,and expression of dual specific phosphate 8 (DUSP-8) and phosphorylation level of MAPK pathway were measured by Western-blot method .Results :Compared with blank control group ,there were significant rise in mi-gration number of THP-1 macrophages [(74.10 ± 15.10) vs.(184.10 ± 26.28)] ,miR-21 expression [(1.00 ± 0.21) vs.(2.02 ± 0.27)] and phosphorylation levels of JNK and P38 protein ,and significant reduction in expression of DUSP-8 protein in ox-LDL group ,P＜0.01 all.Compared with ox-LDL group ,there were significant reductions in migration number of THP-1 macrophages [ (184.10 ± 26.28) vs.(58.50 ± 10.24)] ,miR-21 expression [ (2.02 ± 0.27) vs.(0.66 ± 0.16)] and phosphorylation levels of JNK and P38 protein ,and significant rise in expression of DUSP-8 protein in ox-LDL group , P＜0. 01 all .Conclusion : Ox-LDL enhances migration function of macrophages , which may be related to its effects of upregulating miR-21 expression ,enhancing phosphorylation of JNK and P38 protein of MAPK pathway and reducing DUSP-8 expression .