The Effect Of Tranilast On Proliferation And Apotosis Of Vascular Smooth Musle Cell Of Rat In Vitro Culture And On Secretion Of P57 And C-myc

Objective To observe the effect of Tranilast on proliferation and apoptosis of thoracic aorta vascular smooth musle cell (VSMC) of rat in vitro ,and to study on the potential mechanism.Methods Primary cultures of rat VSMCs were obtained from enzymatically dissociated SD rat thoracic aorta.The experiments were performed using subconfluented cells at passages five through eight. VSMCs were divided into five groups according to different drug concentration.The five groups were 0,12.5,25,50,100mg/L Tranilast group respectively.MTT colorimetry was used for assaying prolixferation of VSMCs after 12,24,48 hours. Apoptosis of cells treated with different concentrations of drugs for 12 hours was observed by flow cytometry and TUNEL Apoptosis Detection Kit.RT-PCR was used for detecting expression of p57 in VSMCs trerted with different concentrations of drugs for 48 hours. expression of c-myc in VSMCs trerted with different concentrations of drugs for 12 hours was detected use RT-PCR too.Result MTT colorimetry found that the cell growth rates in different concentration groups were lower than control. The growth inhibition rate increased with the elevation of Tranilast concentration the prolongation of drug treating time(P〈0.05).This showed Tranilast had a inhibiting effect on VSMC prolifeation in a obvious concentration-depend manner. Gel image showed the p57 expression in VSMC was increased with the elevation of Tranilast concentration after RT-PCR amplification.This suggested that Tranilast may inhibit VSMC proliferation through inducing p57 expression. Apoptosis of VSMC cells detected by flow cytometry and TUNEL Apoptosis Detection Kit showed that apoptotic rate of VSMC was higher than control. And the apoptotic rate was increased with the elevation of Tranilast concentration(P〈0.05). This showed Tranilast had a inductive effect on VSMC apoptosis in a obvious concentration-depend manner. Gel image showed that the c-myc expression in VSMC was decreased with the elevation of Tranilast concentration after RT-PCR amplification. This suggested that Tranilast may induce VSMC apoptosis through inhibit c-myc expression.Conclusion 1 Tranilast had a inhibiting effect on SD rat VSMC prolifeation in a obvious concentration-depend and time- depend manner.Tranilast also had a inductive effect on VSMC apoptosis in a obvious concentration-depend manner.2 Tranilast had a inductive effect on p57 mRNA expression and a inhibiting effect on c-myc expression in SD rat VSMC.And the effect of Tranilast on expression of p57 and c-myc had a obvious concentration-depend manner.3 Tranilast may inhibit VSMC proliferation through inducing p57 expression and induce VSMC apoptosis through inhibit c-myc expression.