[Effect of oxidated low-density lipoprotein on early apoptosis of vascular smooth muscle cell]

Abstract

Objective: To investigate the apoptosis in vascular smooth muscle cell (VSMC) induced by oxidated low-density lipoprotein cholesterol (ox-LDL), and to discuss the relative mechanism of the apoptosis of VSMC.

Methods: The growth index of VSMC of Wistar rat was determined. By using trypan blue to count sustaining cells, the proliferative effect of ox-LDL on culturing VSMC was observed. With flow cytometer, the apoptosis of VSMC induced by ox-LDL and the inhibitory effect of cyclooxygenase-2 (COX-2) inhibitor NS-398 on apoptosis were determined.

Results: After VSMC grew normally in culture, ox-LDL in concentrations of 35 mg/L and 50 mg/L could advance the growth period of VSMC to between 12 and 24 hours, and the proliferation of VSMC were obvious. The proliferation of VSMC induced by ox-LDL were inhibited by NS-398. The rate of apoptosis of VSMC in ox-LDL and NS-398 groups were higher than that of normal control.

Conclusion: ox-LDL could induce an obvious proliferation of VSMC in culture. Although NS-398 can decrease the proliferation of VSMC, it could enhance ox-LDL to induce apoptosis.