Effect Of Overexpressed Daxx On Apoptosis Of Rat Vascular Smooth Muscle Cells Induced By Cholesterol: Model Of β-cyclodextrin

Objective: To investigate the role and mechanism of Daxx on the apoptosis of ratvascular smooth muscle cells(VSMCs) induced by Chol:MβCD.Methods: VSMCs was cultured in vitro.The pcDNA3.1(+), pcDNA3.1(+)-Daxxwere transfected into VSMCs, respectively. And then we detected the expression ofDaxx in gene-transfected VSMCs by RT-PCR and Western blot. After, thegene-transfected VSMCs were incubated with10mg/L Chol:MβCD for48h.Intracellular cholesterol ester content was detected by oil red O staining.The cellvitality was detected by CCK-8assay. The apoptosis rate was detected by flowingcytometry．The expression of ASK1and P-JNK were detected by Western blot．Inorder to further definite the effect of JNK signal transduction pathways in VSMCsapoptosis induced by Chol:MβCD, the specific inhibitor SP600125was used.Results: The RT-PCR and Western blot results showed that the expression of Daxxwas significantly increased in pcDNA3.1(+)-Daxx group. In pcDNA3.1(+)-Daxxgroup, overexpressed Daxx increased obviously the effect of Chol:MβCD onintracellular cholesteryl ester contents, apoptosis and significantly decreased thevitality of VSMCs. Western blot showed ASK1, P-JNK protein level significantlyelevated in pcDNA3.1(+)-Daxx group. SP600125significanfly reduced theexpression of P-JNK and decreased the vitality of VSMCs in pcDNA3.1(+)-Daxx+SP600125group induced by Chol:MβCD.Conclusion: Daxx could promote the apoptosis of VSMCs induced by Chol:MβCD,and its mechanism may relate to the up-regulating of ASK1and JNK expression.