Antiapoptotic Effect Of Probucol On THP-1 Macrophages Apoptosis Induced By Ox-LDL

Aim The study was undertaked to investigate the effects of probucol on theexpression of Daxx, CD36,Caveolin-1,ABCA1,Caspase3 induced by ox-LDL and explore the underling molecular mechanism of probucol protecting THP-1 macrophages against apoptosis induced by ox-LDL.Methods Apoptosis of THP-1 macrophages was determined by flow cytometryanalysis and nucleic acid-binding dye acridin orange. RT-PCR or indirect immunofluorescence was used to detect Daxx, CD36,Caveolin-1,ABCA1,Caspase3 mRNA or protein expression respectively. Western blot was performed to detect Daxx protein expression. Lipids peroxide levels were assessed by measuring intracellular TBARS content.Results Apoptotic rate of THP-1 macrophages induced by 100μ g/mL ox-LDLincreased by time-dependent. After 48 hours of 100μ g/mL ox-LDL treatment, the morphological features typical for apoptosis were apparent in THP-1 macrophages, with the expression of Daxx,CD36,Caveolin-1,ABCA1 upregulated. When the cells were preincubated for 4 hours with 50μmol/L probucol, apoptotic rate of THP-1 macrophages treated by 100 μg/mL ox-LDL for 48 hours decreased from 8.56 + 0.23% to 3.86 ±1.14%, meanwhile, Daxx,Caspase3 mRNA and protein were downregulated. Probucol attenuated Caveolin-1,ABCA1 protein but not mRNA level. However, probucol had no effect on CD36 expression. Intracellular TBARS content reduced from 9.37 + 0.21 to 4.16 + 0.13 nmol/mg protein after the pretreatment with probucol.