对二甲苯及其代谢物对HepG2的细胞毒性效应研究

对二甲苯作为一种重要的苯系物化工原料,生产使用量非常大.进入人体的对二甲苯主要在肝脏中代谢,生成对甲基苄醇和对甲基苯甲酸.目前,关于对二甲苯及其代谢物的肝脏毒性数据仍不够充分.本研究以人肝癌细胞(HepG2)作为实验模型,在细胞层面评价了对二甲苯及其代谢产物(对甲基苄醇和对甲基苯甲酸)的毒性效应,着重探讨了化合物对细胞活力、细胞膜完整性、细胞凋亡的影响.研究结果显示,对二甲苯及其代谢产物对HepG2细胞的急性毒性大小顺序为:对甲基苄醇对甲基苯甲酸对二甲苯.显然,对二甲苯在机体内发生代谢转化后具有毒性增加的趋势.另外,对二甲苯及其代谢产物暴露能够引起细胞膜破损,导致细胞坏死,并诱导一定程度的细胞凋亡现象.该研究发现为对二甲苯作为常见溶剂的生产使用提供了安全性评价的重要科学数据.

The cellular toxicities of p-xylene and its metabolites based on HepG2 cell model

As one of the most important industrial chemicals, p-xylene is widely used in diverse commercial products, including gasoline, paints, glues and thinners. P-xylene is produced in large amount. However, the knowledge on p-xylene and its metabolites'' hepatic toxicity is still far from enough. Based on human hepatocellular carcinoma cell line (HepG2), the cellular toxicities were evaluated for p-xylene and its two main metabolites, 4-methybenzyl alcohol and p-toluic acid. The cellular viability, membrane integrity and apoptosis were investigated upon the treatments of those three chemicals, respectively. The results showed that the toxic potency for these three chemicals was 4-methybenzyl alcohol > p-toluic acid > p-xylene, indicating the metabolism process of p-xylene increased its toxicity. This study provided a new evidence for the risk assessment of p-xylene exposure. Cellular toxicity analysis showed that the integrity of cellular membrane was damaged, which induced the cellular necrosis combined with increased apoptosis by all these 3 chemicals. This study greatly helped to explain the potential risks of p-xylene during its production and usage.