Study of mechanism and inhibition of botulinum toxin type A on hypertrohic scar fibroblasts / 重庆医学

ABSTRACT

Objective To explore the mechanism and inhibition of botulinum toxin type A (BTXA) on hypertrohic scar fibroblasts.Methods The cells were treated by 0 (control),0.2,0.4,0.8 U/ml BTXA for 48 h.Cell viability was detected by MTT assay.Cell apoptosis was detected by Hoechst staining.Cell cycle was detected by flow cytometry.The level of cell cycle related protein D1 (Cyclin D1),proliferation nuclear antigen (PCNA) and activation of phosphatidylinositol 3 kinase (PI3K) / protein kinase B (AKT) signaling pathway were assayed by western blot.Results Compared with control group(0.75±0.07),0.2,0.4,0.8 U/mL BTXA(0.59 ± 0.06,0.43 ± 0.04,0.34± 0.03) inhibited hypertrohic scar fibroblasts cell viability,increased cell apoptotic rate[control group(2.38±0.24)％;BTXA(15.79±1.54)％,(27.32±2.69)％,(38.46±3.90)％],down-regulated the expression of Cyclin D1(control group 1.57±0.18;BTXA 0.93±0.07,0.42±0.04,0.35±0.03) and PCNA(control group 1.46±0.16;BTXA 0.50±0.05,0.59±0.05,0.37±0.03),inhibited the expression of PI3K(control group 0.98±0.06;BTXA 0.49±0.04,0.50±0.04,0.39±0.03) and the phosphorylation of AKT(control group 1.38±0.08;BTXA 0.97±0.06,0.60±0.04,0.29± 0.02),made cell cycle arrested in G1 phase,The difference was statistically significant (P＜0.05).Conclusion These results suggested BTXA inhibit proliferation via blocking the activation of PI3K/AKT signal pathway and down-stream related cell cycle related protein.