HDL2 can inhibit further oxidative modification of partially oxidized LDL

Aim: to investigate whether hdl2 can inhibit further oxidative modification of partially oxidized ldl (ox-ldl) by interrupting the chain oxidation reaction after lipid hydroperoxides (looh) formation. methods: following incubation of ldl 400 μg protein/ml phosphate-buffered saline with cu2+ for 1.75 h (defined as 0 min),incubation was continued after adding hdl2 200 μg protein/ml or hdl2 800 μg protein/ml to give both ox-ldl + hdl2 200 μg protein/ml or ox-ldl + hdl2 800 μg protein/ml. as a control,ox-ldl 200 μg protein/ml and native ldl were prepared. each sample was subjected to agarose gel electrophoresis and the looh in each sample was measured. results: when the electrophoretic mobility of native ldl was designated 1,the relative electrophoretic mobility (rem) of ox-ldl increased significantly over time.the rems of ox-ldl + hdl2 800 μg protein/ml from 10 min to 9 h were significantly lower than the rem of ox-ldl at the respective times (p<0.01). looh of ox-ldl + hdl2 800 μg protein/ml at 1,3,6 and 9 h was significantly higher than looh in ox-ldl at the respective times (p < 0.01). the results of ox-ldl + hdl2 200 μg protein/ml were almost the same but to a lesser extent than the results of ox-ldl + hdl2 800 μg protein/ml. conclusion:the present findings suggest that hdl2 can inhibit further oxidative modification of partially oxidized ldl by interrupting the chain oxidation reaction after looh formation in a concentration-dependent manner.