Abstract:
We investigated the relationship between neutrophil apoptosis and endoplasmic reticulum stress (ERS) in sepsis and its mechanism. A prospective cohort study was conducted by recruiting a total of 58 patients with sepsis. Peripheral blood samples were collected on 1, 3, 5 and 7 days after admission to the ICU. The expressions of endoplasmic reticulum specific glucose regulatory protein 78 (GRP78), C/EBP homologous protein (CHOP), apoptosis signal-regulating kinase 1 (ASK1), Bcl-2-like 11 (BIM), death receptor 5 (DR5), c-Jun N-terminal kinases (JNK) and p38 were detected by Western blot and PCR. The subcellular location of CHOP and GRP78 was observed by immunofluorescence analysis. Spearman correlation was used to analyze the correlation between the expression of chop protein and the apoptosis rate of peripheral blood neutrophils. Healthy volunteers in the same period were selected as the healthy control group. The expression of GRP78 protein was significantly elevated on the first day of ICU admission and showed a decreasing trend on the third, fifth and seventh day, but was significantly higher than the corresponding healthy control group. The expression of CHOP protein reached the highest level on the third day. The expression of chop protein in each group was significantly higher than that in the corresponding healthy control group. Immunofluorescence staining clearly showed that the CHOP protein accumulated in the nucleus, with an elevation in the intensity of GRP78. The neutrophil apoptosis rate of sepsis patients on the 1st, 3rd, 5th and 7th day of ICU stay was significantly higher than that of the healthy control group, with the highest apoptosis rate on the 3rd day, and then decreased gradually. CHOP protein expression level was significantly positively correlated with neutrophil apoptosis rate in sepsis patients. Endoplasmic reticulum stress occurs in neutrophils during the development of sepsis. GRP78 protein and CHOP protein may be involved in the pathological process of neutrophil apoptosis in sepsis.
摘要:
我们研究了脓毒症中性粒细胞凋亡与内质网应激(ERS)的关系及其机制。通过招募总共58名脓毒症患者进行了前瞻性队列研究。在入住ICU后1、3、5和7天收集外周血样本。内质网特异性葡萄糖调节蛋白78(GRP78)的表达,C/EBP同源蛋白(CHOP),凋亡信号调节激酶1(ASK1),Bcl-2-like11(BIM),死亡受体5(DR5),通过蛋白质印迹和PCR检测c-JunN末端激酶(JNK)和p38。通过免疫荧光分析观察CHOP和GRP78的亚细胞定位。采用Spearman相关分析CHOP蛋白表达与外周血中性粒细胞凋亡率的相关性。选取同期健康志愿者作为健康对照组。GRP78蛋白的表达在入住ICU的第1天显著升高,第3天呈下降趋势,第五天和第七天,但明显高于相应的健康对照组。第3天CHOP卵白的表达到达最高程度。各组CHOP蛋白的表达均明显高于相应的健康对照组。免疫荧光染色清楚显示CHOP蛋白在细胞核中积累,GRP78的强度升高。脓毒症患者1日中性粒细胞凋亡率,3rd,第5天和第7天ICU住院时间明显高于健康对照组,第3天凋亡率最高,然后逐渐减少。脓毒症患者CHOP蛋白表达水平与中性粒细胞凋亡率呈显著正相关。在脓毒症的发展过程中,中性粒细胞会发生内质网应激。GRP78蛋白和CHOP蛋白可能参与了脓毒症中性粒细胞凋亡的病理过程。