氯苯甲烷铵和噻吗心胺对人晶状体上皮细胞损伤作用的比较

Comparison of damage of benzalkonium chloride and timolol to human lens epithelial cell

目的了解氯苯甲烷铵和噻吗心胺对人晶状体上皮细胞(LECs)的损伤作用。方法将不同质量浓度氯苯甲烷铵和噻吗心胺作用于人LECs,观察细胞形态变化,并用MTT还原法检测细胞活性,ELISA法检测细胞上清液中所含白介素-1α和前列腺素E2的质量浓度。结果氯苯甲烷铵和噻吗心胺在高质量浓度时直接导致细胞死亡,前者随稀释倍数增加细胞存活率升高,但对细胞的作用转为慢性炎性刺激;后者在稀释20倍时对细胞的炎性刺激最强,随稀释倍数的增加对细胞毒害作用减轻。结论氯苯甲烷铵作为噻吗心胺滴眼液的防腐剂,是对人LECs造成损伤并刺激其强烈分泌IL-1α和PGE2等炎性介质的主要原因。

Objective The apostolic of the human lens epithelial cell has been implied to be the reason for occurrence of the cataract. Some clinical trials showed that benzalkonium chlorid, as one of the composition of timolol maleate, brings some adverse effects on human eye tissue. This research was to investigate the effects of benzalkonium chloride and timolol maleate on human lens epithelial cells（LECs）. Methods Human LECs strains（SRA01/04） was cultured in DMEM containing bovine serum. Different concentrations of benzalkonium chloride and timolol was added into medium. The morphological changes were observed under the inverted contrast phase microscope. The activity of cultured LECs were measured by MTT, and cell-free culture supernatants were collected for the detection of prostaglandin E2 （ PEG2 ） and interleukin 1α（ IL-1α ） by ELISA. Results LECs with both benzalkonium chloride and timolol detached from the culture dish and died within 24 hours. LECs could be disintegrated and elongated in 5 × 10^-2mg/mL of timolol and 1 × 10^-4 mg/mL benzalkonium chloride. The activity of cultured cell was enhanced with the increase of diluting times of benzalkonium chloride and timolol. The amounts of PEG2 and IL-lct depended on the dose of the drugs. When timolol was at 5mg/mL,it killed the cells directly and its secretion of PEG2 and IL-lct was almost stopped. But when it was diluted from 5 × 10^-1 to 5× 10^-2 mg/mL, survival cells increased. Although at the dilution of 0. 25 mg/mL, the secretion of PEG2 and IL-1α showed the highest level（ P 〈 0.05 ）. Benzalkonium chloride, on the other hand, showed continuously chronic inflammatory stimulate：the secretion of PEG2 and IL-lct elevated even if it was diluted, and peaked at 1 × 10^-4 mg/mL （ P 〈 0. 05 ）. Conclusion Benzalkonium chloride induces the damage of human LECs, and it strongly stimulates the cultured LECs to secrete the inflammatory mediators.