细胞焦亡在急性CO中毒迟发性脑病中的作用机制研究

Study on mechanism of pyrolysis in acute CO poisoning and delayed encephalopathy

目的:对细胞焦亡参与的急性一氧化碳(CO)中毒迟发性脑病(DEACMP)的作用机制进行研究。方法:将经过Morris水迷宫筛选后的120只SD大鼠随机分为空气组(K组)、CO中毒组(CO组)、CO+Ac-YVAD-cmk组(cmk组)。各组再按照时间顺序随机分为1 d、3 d、7 d、14 d、21 d 5个亚组。Morris水迷宫实验检测大鼠学习记忆能力损伤情况,Western blot检测NLRP3、cleaved-caspase-1、GSDMD蛋白的动态表达,免疫组化检测caspase-1阳性细胞表达,ELISA检测成熟IL-1β和IL-18表达。结果:染毒后第14天及第21天,CO组及cmk组较K组逃避潜伏期延长、穿越平台次数减少(P<0.05)。中毒后各时间点CO组及cmk组中NLRP3、cleaved-caspase-1及GSDMD蛋白具有相似的表达趋势,均于染毒第3天及第14天出现峰值(P<0.05)。CO组及cmk组caspase-1阳性细胞数在染毒第14天均达到峰值,且两组IL-1β及IL-18蛋白水平均在染毒第14天表达最为显著。结论:细胞焦亡参与了大鼠DEACMP的发生,二者具有时间依赖性,抑制细胞焦亡有利于减轻CO中毒后大鼠认知功能的损伤。

Objective:To study the mechanism of acute carbon monoxide(CO)poisoning and delayed encephalopathy(DEACMP)involved in pyrolysis.Methods:A total of 120 SD rats after being screened by the Morris water maze were randomly divided into air group(K group),CO poisoning group(CO group),CO+Ac-YVAD-cmk group(cmk group).Each group was randomly divided into 5 subgroups of 1,3,7,14,and 21 d in chronological order.The impairment of learning and memory ability of rats were detected by Morris water maze test,Western blot was uesd to detect the dynamic expressions of NLRP3,cleaved-caspase-1,GSDMD protein,immunohistochemistry was uesd to detect the expression of caspase-1 positive cells,ELISA was uesd to detect mature IL-1βand IL-18expressions.Results:On the 14th and 21st day after exposure,the escape latency of CO group and cmk group were longer than that of K group,and the number of crossing platform was less(P<0.05).The expression trends of NLRP3,cleaved caspase-1 and GSDMD proteins in CO group and cmk group were similar at each time point after poisoning,and the peaks appeared on day 3 and day 14 after poisoning(P<0.05).The number of caspase-1 positive cells in CO group and cmk group reached the peak on the 14th day of exposure,and the expressions of IL-1βand IL-18 protein in both groups was the most significant on the 14th day of exposure.Conclusion:Pyrolysis is involved in the occurrence of DEACMP after acute CO poisoning in rats,and both are time-dependent.Inhibition of pyrolysis is benificial to reduce the cognitive function damage of rats after CO poisoning.