Objective: To study the effect of inflammatory factors on cell proliferation and apoptosis in insulin-like grown factor 1 (IGF1)-slienced human coronary artery smooth muscle cells (hCASMCs).
Methods: We silenced the expression of IGF1 in hCASMCs using the lentivirus-mediated RNA interference technology. Blank control group and negative control group were set using the hCASMCs without the infection of a virus vector and the hCASMCs with the infection of a negative control virus vector, respectively. After the treatment of these cells with both tumor necrosis factor-α 50 ng/ml and interleukin-1β 40 ng/ml, the concentration of IGF1 in cell-culture medium was detected by enzyme-linked immunosorbent assay, and the proliferation and apoptosis were evaluated by MTT assay and flow cytometry.
Results: After the simulation with inflammatory factors, the concentration of IGF1 in the supernatant fluid of cultured IGF1-slienced hCASMCs was significantly lower than those in the blank control group and negative control group [(426.35±120.96) vs. (1 030.69±54.69) and (992.82±26.90)pg/ml, P=0.000). The proliferation of IGF1-slienced hCASMCs was substantially much less than the two control groups (0.302±0.011 vs. 0.401±0.028 and 0.302±0.011, F=37.628, P=0.000), and the apoptosis rate of IGF1-slienced hCASMCs was significant increased compared with the other two groups [(10.57±0.99)% vs. (0.19±0.13)% and (1.31±0.30)%, P=0.001].
Conclusion: Inflammatory factors can inhibit the cell proliferation and promote apoptosis after the knock-down of IGF1 in hCASMCs.