纳米银对肝细胞体外增殖作用的实验研究

Effect of silver nanoparticles on proliferation of hepatic cells: an experimental study in vitro

目的探讨纳米银及其释放的银离子对人肝癌（HepG2）细胞株及人正常肝（L02）细胞株体外增殖的影响。方法采用CCK-8法检测纳米银（20-640μg/ml）染毒24、48 h对Hep G2细胞及L02细胞两株细胞体外增殖的影响,并以纳米银释放的银离子作为平行对照,以相同银含量的硝酸银溶液及相同包被含量的聚乙烯基吡咯烷酮（polyvinyl pyrrolidone,PVP）溶液分别作为阳性对照和阴性对照。采用LDH法测定纳米银（20-160μg/ml）染毒24、48 h对两株细胞膜渗透性的影响。结果纳米银暴露24 h后,HepG2细胞各剂量组和L02细胞160μg/ml以上剂量组细胞存活率均低于对照组;暴露48 h后,两株细胞各剂量组（除L02细胞染毒20μg/ml以外）细胞存活率均低于对照组,且均低于相同浓度暴露24 h组（P〈0.05或P〈0.01）。纳米银溶液经超速离心法获得的银离子对两株细胞存活率无明显影响,而对应剂量硝酸银溶液的细胞毒性远高于纳米银。两株细胞各剂量组细胞外液LDH活性均高于对照组,且在相同条件下,HepG2细胞外液LDH活性明显高于L02细胞,差异均有统计学意义（P〈0.05或P〈0.01）。结论纳米银对HepG2和L02细胞均具有增殖抑制效应,其作用主要由纳米银单体引起,且对HepG2细胞影响更明显。

Objective To explore the influence of silver nanoparticles（AgNPs） and silver ions released from AgNPs on the proliferation of human hepatoma cell line（HepG2） cells and human normal liver cell line（L02） cells in vitro. Methods HepG2 and L02 cells were exposed to AgNPs（20-640 μg/ml） for 24,48 h. Cell viability was examined by CCK-8 assay. Toxicity of silver ions released from Ag NPs was investigated simultaneously. Silver nitrate solution with the same silver content and polyvinyl pyrrolidone（PVP） solution with the same content of coated material were used as positive and negative controls respectively. Cell membrane damage was examined by lactate hydrogenase（LDH） assay. Results After 24 hours of treatment with Ag NP solution, the survival rates of HepG2 cells in all treatment groups and the survival rates of L02 cells in higher dosage groups（160,320,640 μg/ml） were significantly lower than the control group（P〈0.05,P〈0.01）. After 48 hours of the treatment,the survival rates of two cell lines in all treatment groups,except for the L02 cells at 20 μg/ml,were significantly lower than the control group and the 24 h treatment groups（P 0.05,P 0.01）. Silver ion released from Ag NP solution by ultracentrifugation had little effect on cell vitality. It was found that the cytotoxicity of silver nitrate was much higher than that of Ag NPs. Furthermore,the cell membrane permeability assay showed LDH activity in culture medium of two cell lines were higher than the control group（P〈0.05,P〈0.01）. Under the same exposure condition,LDH activity in culture medium of HepG2 cells was much more higher than L02 cells（P〈0.01）. Conclusion Ag NPs has a proliferation inhibition effect on HepG2 and L02 cell lines,which is mainly caused by nanosilver monomer. HepG2 cells is more sensitive to Ag NPs than L02 cells.