神经生长因子对大鼠肝星状细胞转化生长因子-β_1及Smad蛋白通路的影响

Influence of nerve growth factor on transforming growth factor-β_1 and Smad protein pathway in rat hepatic stellate cell

目的研究神经生长因子(NGF)对大鼠肝星状细胞-T6(HSC-T6)增殖、凋亡的影响以及大鼠HSC-T6中转化生长因子-β_1(TGF-β_1)/Smad蛋白通路的变化,探讨NGF影响HSC-T6增殖及凋亡的可能作用机制。方法体外培养大鼠HSC-T6,将HSC-T6与不同浓度的NGF孵育,分为对照组(0 ng/ml NGF)、实验组(100 ng/ml NGF),应用流式细胞术检测HSC-T6凋亡情况,通过XTT法了解NGF对HSC-T6增殖的影响;免疫细胞化学法观察NGF对HSC作用后TGF-β_1、Smad3、Smad7表达的变化。结果实验组(OD值为0.65±0.03)对HSC-T6的增殖抑制作用与对照组(OD值为0.73±0.01)比较,差异有统计学意义(P<0.05)。实验组的凋亡率高于对照组,差异有统计学意义(P<0.05)。与对照组比较,实验组的TGF-β_1、Smad3表达明显降低,Smad7表达明显升高(P<0.05)。结论 NGF可抑制HSC-T6增殖、促进其凋亡,其机制可能与调节TGF-β_1/Smad蛋白通路有关。

Objective To study the influence of nerve growth factor（NGF） on the proliferation and apoptosis of hepatic stellate cell-T6（HSC-T6） and transforming growth factor-β1（TGF-β1）/Smad protein pathway change in HSC-T6 of rat,and explore the possible mechanism of NGF influencing HSC-T6 proliferation and apoptosis. Methods HSC-T6 of rat was cultured in vitro. HSC-T6 was incubated with different concentrations of NGF and divided into the control group（0 ng/ml NGF） and experimental group（100 ng/ml NGF）. The flow cytometry was used for detection of HSC-T6 apoptosis.By XTT, the influence of NGF on the proliferation of HSC-T6 was understood. The expression of TGF-β1, Smad3 and Smad7 after NGF affecting on HSC was observed by immunocytochemistry. Results The inhibition of HSC-T6 proliferation in the experimental group（OD value was 0.65±0.03） was significantly different from that in the control group（OD value was 0.73±0.01）（P〈0.05）. The apoptosis rate of the experimental group was higher than that of the control group with a statistical difference（P〈0.05）. The expression of TGF-β1 and Smad3 in the experimental group was down-regulated significantly, while the expression of Smad7 was greatly up-regulated compared with those in the control group（P〈0.05）. Conclusion NGF can inhibit the proliferation of HSC-T6 and promote its apoptosis. The mechanism may be related to the regulation of TGF-β1/Smad protein pathway.