全反式维甲酸对亚砷酸钠致人肝细胞损伤保护性作用的研究

Protective effect of all-trans retinoic acid on injury of human immortalized hepatocytes induced by sodium arsenite

目的观察全反式维甲酸（ATRA）对亚砷酸钠致人肝细胞系（HHL）-5细胞损伤的保护性作用。探讨可能机制。方法采用细胞培养方法，体外培养HHL-5细胞48h后进行实验，实验分为4组：正常组、ATRA组、亚砷酸钠组、ATRA＋亚砷酸钠组。用细胞增殖实验（WST）观察HHL-5细胞的活力；生物化学方法测定各组HHL-5细胞内超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH—Px）的活力及丙二醛（MDA）的含量和细胞培养液中谷草转氨酶（AST）的活力；透射电镜观察各组细胞超微结构的变化。结果亚砷酸钠组HHL-5细胞活力（0．57±0．02）与正常组（0．70±0．01）比较，差异有统计学意义（P〈0．05）：SOD、GSH-Px、MDA、AST[（153．84±2．35）U／mgProt、（0．08±0．02）U／mgProt、（4．15±0．50）nmol／mgProt、（265．43±4．62）×10 -3U／L]与正常组[（237．41±18．30）U／mgProt、（0．93±0．02）U／mg Prot、（2．26±0．40）nmoL／mgProt、（177±9．85）×103U／L]比较，差异有统计学意义（P均J〈0．05）。ATRA＋亚砷酸钠组HHL-5细胞活力（0．65±0．04）与亚砷酸钠组比较，差异有统计学意义P〈0．05）；SOD、GSH—Px、MDA、AST[（286．85±3．39）U／mgProt、（0．56±0．09）U／mgProt、（3．36±0．37）nmol／mgProt、（220．02±1．07）×10 3U／L]与亚砷酸钠组比较，差异有统计学意义（P均〈0．05）。电镜结果显示，亚砷酸钠组同正常组及ATRA组比较，细胞表面微绒毛减少，双层核膜结构不清，胞质内可见空泡样变，肝糖原凝集；ATRA＋亚砷酸钠组上述损伤程度减轻。结论ATRA通过提高HHL-5细胞内抗氧化酶的活力。清除或者减少氧自由基对细胞的损伤，从而发挥保护作用。

Objective To investigate the protective effect of all-trans retinoic acid （ATRA） on injury of human immortalized hepatoeytes （HHL-5 cells ） induced by sodium axsenite and possible mechanisms. Methods After cultured for 48 h, HHL-5 cells were divided into four groups ： normal group, ATRA group, sodium arsenite group and ATRA ± sodium arsenite group. HHL-5 cell viability was tested by using cell proliferation experiment （WST）. Superoxide dismutase（SOD）, glutathione peroxidase（GSH-Px） activity, malondialdehyde（MDA） content, and aspartate aminotransferase （AST） activity in each group were determined by biochemical method. The microstructure of HHL-5 cells in each group was observed under transmission electron microscopy. Results HHL- 5 cell viability（0.57 ± 0.02） of sodium arsenite group was compared with that of normal group（0.70 ± 0.01 ）, the difference was statistically significant（P 〈 0.05）. Levels of SOD, GSH-Px, MDA and AST[ （153.84 ± 2.35）, （0.08 ±0.02）U/mg Prot, （4.15 ± 0.50）nmol/mg Prot, （265.43 ± 4.62） × 10 3 U/L] of sodium arsenite group were compared with that of normal group[ （237.41 ± 18.30）, （0.93 ± 0.02）U/mg Prot, （2.26 ± 0.40）nmol/mg Prot, （177 ± 9.85） × 10 3 U/L], and the difference was statistically significant （all P 〈 0.05）. HHL-5 cell viability （0.65 ± 0.04） of ATRA ± sodium arsenite group was compared with that of sodium arsenite group; and the difference was statistically significant （P 〈 0.05）. Levels of SOD, GSH-Px, MDA and AST[ （286.85 ± 3.39）, （0.56 ± 0.09）U/mg Prot, （3.36 ± 0.37）nmol/mg Prot, （220.02 ± 1.07） × 10 3 U/L] of ATRA＋ sodium arsenite group were compared with that of sodium arsenite group, the difference was statistically significant（all P 〈 0.05）. Compared with normal group and ATRA group, the surface microvilli of HHL-5 cells of sodium arsenite group decreased, double-membrane structure was unclear, vacuolar degeneration was seen in the cytoplasm, and glycogen was aggregated. The damage level of ATRA ＋ sodium arsenite group was deereased. Conclusions ATRA plays a protective role through increasing intraeellular antiondant enzyme activity of HHL-5 cells, removal or reduction of oxygen free radicals produced by sodium arsenite.