远志抽提物DX-1对神经母细胞瘤分化的诱导作用

目的观察神经母细胞瘤细胞分化诱导后形态学改变和端粒酶活性的变化.方法用中药远志抽提物1,7-二羟夹氧蒽酮(DX-1)诱导神经母细胞系Neuro-2A细胞分化,观察分化后瘤细胞的存活率、细胞倍增时间,以及细胞轴突树状突形成、长短和数目,并用TRAP银染法检测分化前后瘤细胞端粒酶活性的改变.结果用DX-1处理后,Neuro-2A细胞生长受明显抑制,其倍增时间延长1.1～13.0倍.在高剂量组(0.1mmol/L)大部分细胞死亡,仅存少量细胞分化成熟.各处理组的瘤细胞呈现神经细胞分化,胞浆具有轴突和树状突样突起,一些突起互相对接,或交织成网状结构.然而,经中、低剂量DX-1作用后,瘤细胞端粒酶活性未见明显的差异,仅在高剂量时端粒酶活性明显下降,甚至完全消失.结论DX-1可诱导体外培养的Neuro-2A细胞分化.在中、低剂量时,瘤细胞出现轴突和树状突突起.在高剂量时,DX-1对瘤细胞有一定的抑制和杀灭作用.在瘤细胞分化过程中,端粒酶活性并不出现明显的变化.

Study on telomerase activity during induction of axon-like and dendrite-like processes in neuroblastoma cells.

Objective To observe telomerase activity change during differentiation induction of neuroblastoma cells. Methods Differentiation of neurobalstoma cells was induced by 1,7-dihydroxanthone (DX-1) extracted from polygala caudata, doubling time, length and number of axon-like and dendrite-like processes induced were observed during the differentiation of the cells. Telomerase activity was detected by TRAP-silver staining method. Results After treatment with DX-1, proliferation of neuroblastoma cells was inhibited significantly. The population doubling time of the cells prolonged 1.1 - 13.0 times. Most of cells died but some differentiated into mature neuron-like cells in high dose of DX-1 treatment. Exposure to DX-1 induced axon-like and dentrite-like process outgrowth along with cell body which crossed as a net or contacted end to end. However, telomerase activity did not changed markedly in the cells after treated with middle or low dose of DX-1. Only in high dose group telomerase activity decreased and eventually disappeared. Conclusions DX-1 may induce in vitro differentiation of neuroblastoma cells and give rise to neuriles with axon-like and dendrite-like characteristics in the cells. High dose of DX-1 inhibits proliferation and affects survival of neuroblastoma cells. Telomerase activity of the cells, however, does not change remarkably during the differentiation of the cells.