铁磁流体联合交变磁场对人肝癌细胞HepG2的影响

Effects of ferromagnetic fluid hyperthermia induced by an alternative magnetic field on hepatoma cell HepG2 in vitro

目的探讨一定的交变磁场不同浓度Fe304磁流体热疗对人肝癌细胞HepG2的影响。方法在肝细胞的培养液中分别加入不同浓度的Fe304磁流体,暴露在交变磁场中30min后,采用MTT法、细胞计数、光镜、荧光显微镜、流式细胞仪等观察经过上述药物处理后,肝癌细胞活细胞数的光密度值、杀伤率、生长曲线、细胞形态变化、细胞周期及凋亡情况。结果随着磁流体中Fe304纳米粒浓度的增加,①细胞培养液的温度分别上升到38.9～47.2℃;Fe304浓度≥4.5mg/mL时,温度>41℃;②细胞增殖抑制增强,肝癌细胞活细胞数的光密度值下降,杀伤率(cytotoxity index,CI)增加;当Fe304浓度≥4.5mg/mL时,CI≥50%,CI最高达85.91%,呈明显的量效关系(P<0.001);③细胞核染色质凝聚、浓缩,有的成半月形或梅花瓣状改变,尤以Fe304浓度≥4.5mg/mL时变化明显;④细胞周期停滞于S期,S期细胞增加,凋亡率增加;Fe3O4浓度从4.5mg/mL增加到6.0mg/mL时,凋亡率分别由27.06%增加到66.05%;Fe3O4浓度为3.0mg/mL时,温度为39.8℃<40℃,凋亡率为14.22%(P<0.001)。结论交变磁场作用下,随Fe3O4浓度增加,温度升高,磁流体对人肝癌细胞HepG2毒性增强,细胞凋亡增加;磁流体中Fe3O4浓度与其成明显的量效依赖关系。

[Objective] To study effects of nano-ferroferrie oxide magnetic fluid with varying concentration hyperthermia induced by an alternating magnetic field on hepatoma cell HepG2 in vitro. [Methods] A human hepatoma cell HepG2 was cultured with vireus concertration of ferroferric oxide （Fe3O4, 68 nm） magnetic fuid （1.5-7.5） mg/mL and exposed to an alternative magnetic field （AMF） with 100 kHz and 15 kA/m for 30 min, meanwhile temperatures were measured by optical fiber transducer thermometer. The optic density （OD） of viable cell, cytotoxity index, growth curve of cells, morphologic changes of cell, cell cycle and aposptosis were assayed by MTT method, cell count, light and fluorescence microscope and flow eytometry. [Result] With the increase of concentration of Fe3O4, the following outcomes occurred, including： ①the temperature of the culture medium was 38.9-47.2℃; above 41℃ was got with the concentration of Fe3O4 〉/ 4.5 mg/mL; ② the proliferation of HepG2 cell was increasingly inhitibited, the OD value of viable cell decreased and eytotoxity index （CI） increased; CI exceeded 50% with the eoneentralion of 4.5 mg/ml Fe3O4; the effect was concentration-dependent （P 〈0.001）. ③the apoptotie HepG2 cell were observed to have cell shrinkage, ehrematin condensation, margination, unclear fragmentation, apoptotic bodies, and intact cell membrane. The typical eytomorpho-logieal features of apoptosis was more obvious when the concentration of Fe3O4 exceeded 4.5 mg/ml. ④the cycle of HepG2 cell was inhibiteded in the stage S, the percentage of cells in the stage S increase; the ratio of apeptosis of HepG2 cell increased and it was up to 27.06-66.05% with the concentraton of Fe3O4 ranging from 4.5 mg/mL to 6.0 mg/mL; the apeptosis rate 14.2% with the 3.0 mg/ml Fe3O4 （P 〈0.001）. [Conclusion] Ferromagnetic fluid hyperthermia induced by AMF could inhibit the proliferation and promote apeptosis of human hepatoma HepG2 cells in a concentration-dependent manner.