[Objective] To study regulation effects of Coenzyme Q10( Co Q 10) on the oxidized low-density lipoprotein( ox-LDL)-induced proliferation of rat vascular smooth muscle cells( VSMCs). [Methods]After incubation of ox-LDL( 0,10,20,30,40,50,60,70,80 mg /L) and Co Q 10( 0,10,20,30,40,50,60,70,80 μmol / L) on logarithmic growth phase vascular smooth muscle cells for 24 hours,respectively,CCK-8 method was used to detect the proliferation index of VSMCs,and screen ox-LDL model concentration and cytotoxicity of Co Q 10.Cell were divided into the control group,model group,Co Q10 low concentration,medium concentration,and high concentration. After drug action for 24 hours,except the normal group,a1 l groups were given culture solution containing screened concentration of ox-LDL to reproduce proliferation model of VSMCs. Mitochondrial protein was extracted,and protein levels of Cytochrome C( Cyto-C) and apoptosis inducing factor( AIF) were detected by Western blotting technique. [Results]Compared with the control group,the model group had higher cell survival rate and protein levels of Cyto-C and AIF,and the difference showed statistical significance( p < 0. 05); compared with the model group,Co Q 10 low,medium,and high concentration groups had low cell survival rate,higher protein levels of Cyto-C and AIF,and the difference showed statistical significance( p < 0. 05). [Conclusion]Co Q 10 can inhibit abnormal proliferation VSMCs through promoting protein expression of Cyto-C and AIF. [Objective] To study regulation effects of Coenzyme Q10 (Co Q 10) on the oxidized low-density lipoprotein (ox-LDL) -induced proliferation of rat vascular smooth muscle cells (VSMCs). [Methods] After incubation of ox- 0, 10, 20, 30, 40, 50, 60, 70, 80 mg / L) and Co Q 10 CCV-8 method was used to detect the proliferation index of VSMCs, and screen ox-LDL model concentration and cytotoxicity of Co Q 10. Cells were divided into the control group, model group, After the drug action for 24 hours, except the normal group, a1 l groups were given culture solution containing screened concentration of ox-LDL to reproduce proliferation model of VSMCs. Mitochondrial protein was extracted, and protein levels of Cytochrome C (Cyto-C) and apoptosis inducing factor (AIF) were detected by Western blotting technique. [Results] Compared with the control group, the model group had higher cell survival rate and protein levels of Cyto-C and AIF, and the difference showed statistical significance (p <0.05); compared with the model group, Co Q 10 low, medium, and high concentration groups had low cell survival rate, higher protein levels of Cyto-C and AIF, and the difference showed statistical significance (p <0.05). [Conclusion] Co Q 10 can inhibit abnormal proliferation VSMCs through promoting protein expression of Cyto-C and AIF.