Abstract:Aim To investigate the effect of oxidized low density lipoprotein (ox-LDL) on activation of PPARγ-LXRα-ABCA1 pathway via lectin-like oxidized low density lipoprotein receptor-1 (LOX-1) receptor. Methods The expression of liver X receptor α (LXRα) and ABCA1 was detected by stimulating J774A.1 macrophages with concentration gradient ox-LDL (0~40 mg/L, 12 h), the expression of LOX-1 was detected by laser confocal microscopy and Western blot, the transcriptional activation of peroxisome proliferators-activated receptor γ (PPARγ) was detected by double luciferase reporter gene, the expression of LXRα and ATP-binding cassette transporter A1 (ABCA1) protein was detected after incubation with J774A.1 macrophages by LOX-1 siRNA and PPARγ siRNA silencing, ox-LDL (30 mg/L,12 h). Results Ox-LDL significantly up-regulated the expression of LXRα and ABCA1 in J774A.1 cells (significantly different from the cell untreated by ox-LDL as control, P<0.01, n=3). LOX-1 overexpression of PPARγ double luciferase reporter gene system showed that ox-LDL increased the transcriptional activity of PPARγ by LOX-1. LOX-1 siRNA and PPARγ siRNA were treated with J774A.1 macrophages, respectively, and LXRα and ABCA1 were expressed (significantly different from the cell untreated by siRNA as control, P<0.01, n=3). Conclusion Ox-LDL activates PPARγ transcriptional activity by LOX-1 receptor, thereby upregulating LXRα and ABCA1 protein expression and activating PPARγ-LXRα-ABCA1 signal pathway.