| Purpose. The heat shock response is an immediate celluar response to elevated temperature and other types of injury that consists of the synthesis of so-called heat shock proteins (Hsps). This study was designed to investigate the dynamic expression of Hsp70 and Hsp27 in lens epithelial cells (LECs) in contused eyes of rat model, and to study the effects of heat shock and Quercetin on them.
Methods. Eyes were randomized into three groups as contusion group, heat shock group and Quercetin group. Eyes contusion were induced by dropping a steel ball of 20g from the height of 20cm for 100 times. Heat shock was induced by raising the core body temperature to 40.5℃-41.5℃ for 8 minutes, 2-3 hours before eyes contusion. Quercetin， an inhibitor of Hsp expression, was given via gavage (100mg/kg) 2-3 hours before eyes contusion. Experimental eyes of SD rats were enucleated at 0, 1, 3, 6 and 24 hours following each group for the detection of HSP70 and HSP27 expressions in LECs using one-tube RT-PCR. The eyes of normal, contusion group, heat shock group and Quercetin group were studied by immunohistochemistry. The sections of lens were examined after immunostaining with antibodies to HSP70.
Results: There were basic expression of Hsp70 and Hsp27 in LECs. Expression of Hsp70 in LECs was increased after hitting of eyes. Blunt traumatic of eyes induced increasing expression of HSP70 in LECs and time dependent. Preconditioning hyperthemia(45℃, 8min) resulted in significantly increase of HSP70 expression than basic expression. However, HSP70 level of 1h-6h group in Quercetin group was significantly lower than that in contusion group. There was no notable change of expression of HSP27 in each group. Immunostaining of Hsp70 was prominent in LECs of contusion eyes and heat shock eyes compared with those of normal eyes. Immunostaining of Hsp70 was prominent faint in LECs of Quercetin eyes compared with heat shock eyes.
Conclusion：Blunt traumatic of eyes induced increasing expression of HSP70 in LECs and time dependent. Preconditioning hyperthemia resulted in significantly increase of HSP70 expression in LECs. Quercetin via oral preconditioning decrease the expression of HSP70 in LECs of contusion eyes, it possibly occur at cell transcription level. Increasing expression of HSP70 in LECs of contusion eyes may play a protective role against degeneration of lens protein. Thermal preconditioning possibly protect against lens injury induced by contusion by increasing the expression of HSP70. Endogenous protective mechanisms may be important in eyes contusion injury.
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