The role of high mobility group protein 1 mediated the endoplasmic reticulum stress in cerebral ischemia/reperfusion injury
10.3760/cma.j.issn.2095-4352.2016.04.015
- VernacularTitle:高迁移率族蛋白B1介导内质网应激在脑缺血/再灌注损伤中的作用
- Author:
Jing ZHAO
;
Wenjing GENG
;
Bozhi ZHAI
;
Yijun SONG
- Publication Type:Journal Article
- Keywords:
High mobility group protein 1;
Endoplasmic reticulum stress;
Hypoxia/reoxygenation;
Brain ischemia/reperfusion injury
- From:
Chinese Critical Care Medicine
2016;28(4):364-368
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the mechanism of high mobility group protein 1 (HMGB1) involved in endoplasmic reticulum stress (ERS) induced by brain ischemia/reperfusion (I/R),based on I/R-HMGB1-ERS as the breakthrough point.Methods The brain of rats birthed 1-3 days was harvested,and the brain cells were cultured in vitro,which were used in the experiment when the cells were in the third passage.The cells were divided into two groups:cells in blank control group were cultured under the normal conditions without any treatment,and the cells in hypoxia/reoxygenation group were cultured with 99.9％ nitrogen for 60 minutes (hypoxia) followed by opening the bottle neck for reoxygenation 120 minutes to simulate I/R model.The HMGB1 gene was silenced by using small interfering RNA (siRNA,siRNA and transfection reagent Lipofectamine 2000 mixture gradient was transfected into the cultured cells) as HMGB1-siRNA transfection group,and blank control (without any treatment) and negative control group (transfected with control siRNA) served as controls.The mRNA and protein expressions of HMGB1 and ERS related molecules were determined by real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western Blot.Results ① In cells of hypoxia/reoxygenation group,the mRNA and protein expressions of HMGB1 and ESR related proteins,including glucose regulating protein 78 (GRP78),C/EBP homologous protein (CHOP) and caspase-12,were significantly higher than those of blank control group with statistical difference (the value in blank control group was served as baseline 1,HMGB1 mRNA:3.19±0.48 vs.1,t =2.183,P =0.008;GRP78 mRNA:2.07±0.33 vs.1,t =3.292,P =0.016;CHOP mRNA:1.93±0.28 vs.1,t =2.573,P =0.021;caspase-12 mRNA:2.42±0.42 vs.1,t =2.261,P =0.027:HMGB1 protein:2.28±0.36 vs.1,t =2.042,P =0.009;GRP78 protein:1.33±0.24 vs.1,t =2.781,P =0.016;CHOP protein:1.67±0.34 vs.1,t =2.174,P =0.021;easpase-12 protein:1.36±0.44 vs.1,t =3.192,P =0.008).It was indicated that ERS related molecules involved in cell hypoxia/reoxygenation process.2② After HMGB1 gene was silenced by siRNA,the cells after hypoxia/reoxygenation showed a decrease in the mRNA and protein expressions of HMGB1 and ERS related moleculars as compared with those of blank control group and negative control group (served the value in blank control group as baseline 1,HMGB1 mRNA:0.27±0.12 vs.1,1.02 ± 0.04;GRP78 mRNA:0.16 ± 0.13 vs.1,0.96 ± 0.04;CHOP mRNA:0.47 ± 0.09 vs.1,0.98 ± 0.07;caspase-12 mRNA:0.31 ±0.11 vs.1,1.05±0.02;HMGBI protein:0.23±0.04 vs.1,1.08±0.01;GRP78 protein:0.14±0.09 vs.1,1.35±0.03;CHOP protein:0.32±0.10 vs.1,0.93±0.06;caspase-12 protein:0.27±0.09 vs.1,0.97±0.08;P ＜ 0.05 or P ＜ 0.01).It was indicated that HMGB1 involved in ERS related with GPR7,CHOP,caspase-12.Conclusion Hypoxia/reoxygenation brain intracellular HMGB1 and ERS related molecules expression levels were significantly up-regulated,and silencing HMGB1 gene can significantly inhibit the expression levels of these molecules,and I/R-HMGB 1-ERS pathway may participate in the mechanism of brain I/R injury.
