Abstract:

To evaluate the effect of small interference RNA(siRNA) on Cystatin C in human vascular smooth muscle cells and its effect on expression of Cathepsin S. MethodssiRNA targeting Cystatin C was constructed by an online design of Ambion company and transfected into human vascular smooth muscle cells. The nontransfected cells and cells treated with the control siRNA served as controls. mRNA and protein expressions of Cystatin C were detected by RTPCR and Western blot respectively. Compared with the nontransfected cells, cells treated with control siRNA and cells highly expressing Cystatin C,  the mRNA and protein expressions of Cathepsin S in cells treated with control siRNA whose interfering rate was the highest were detected by RTPCR and Western blot respectively. ResultsAt 24hour posttransfection,  mRNA and protein expressions of Cystatin C were efficiently inhibited in siRNA treated cells compared with the control cells(P<0.01), especially in siRNA2 treated cells. mRNA and protein expressions of Cathepsin S were significantly increased in the siRNA treated group compared with the other three groups (P<0.01). ConclutionsiRNA in vitro transcription can inhibit Cystatin C gene expression in human vascular smooth muscle cells, which may effect expression of Cathepsin S.

Key words: Gene expression; Cystatin C; Cathepsin S; Vascular smooth muscle cell