Table_3_Nrf2 functions as a pyroptosis-related mediator in traumatic brain injury and is correlated with cytokines and disease severity: a bioinformatics analysis and retrospective clinical study.docx

BackgroundTraumatic brain injury (TBI) is a serious hazard to human health. Evidence has accumulated that pyroptosis plays an important role in brain trauma. The aim of this study is to screen potential key molecules between TBI and pyroptosis, and further explore their relationships with disease severity and cytokines.
MethodsTo acquire differentially expressed genes (DEGs) before and after brain injury, the GSE89866 dataset was downloaded from the Gene Expression Omnibus (GEO) database. Meanwhile, pyroptosis-related genes were obtained from the GeneCards database, and the intersected genes were identified as differentially expressed pyroptosis-related genes (DEPGs). Moreover, the hub genes were screened via four algorithms (namely Maximum Clique Centrality, Edge Percolated Component, BottleNeck and EcCentricity) in Cytoscape software. Blood levels of Nrf2 were measured by ELISA using a commercially available kit. Finally, we further investigated the correlation between Nrf2 levels and medical indicators in TBI such as clinical characteristics, inflammatory cytokines, and severity.
ResultsAltogether, we found 1,795 DEGs in GSE89866 and 98 pyroptosis-related genes in the GeneCards database. Subsequently, four hub genes were obtained, and NFE2L2 was adopted for further clinical study. By using Kruskal-Wallis test and Spearman correlation test, we found that the serum Nrf2 levels in severe TBI patients were negatively correlated with GCS scores. On the contrary, there was a positive correlation between serum Nrf2 levels and pupil parameters, Helsinki CT scores, IL-1 β and IL-18.
ConclusionsIn summary, bioinformatic analyses showed NFE2L2 plays a significant role in the pathology of TBI. The clinical research indicated the increase in serum Nrf2 levels was closely related to the severity of trauma and cytokines. We speculate that serum Nrf2 may serve as a promising biochemical marker for the assessment of TBI in clinical practice.

【背景】创伤性脑损伤（Traumatic brain injury, TBI）是严重危害人类健康的疾病。现有研究证据表明，焦亡（pyroptosis）在脑创伤病理过程中发挥重要作用。本研究旨在筛选创伤性脑损伤与焦亡相关的潜在关键分子，并进一步探讨其与疾病严重程度及细胞因子的关联。
【方法】为获取脑损伤前后的差异表达基因（differentially expressed genes, DEGs），本研究从基因表达综合数据库（Gene Expression Omnibus, GEO）下载GSE89866数据集。同时，从GeneCards数据库获取焦亡相关基因，取二者交集得到差异表达焦亡相关基因（differentially expressed pyroptosis-related genes, DEPGs）。此外，借助Cytoscape软件中的四种算法（即最大clique中心性、边缘渗滤分量、瓶颈算法和离心度算法）筛选核心基因。采用商业化试剂盒通过酶联免疫吸附试验（ELISA）检测血清Nrf2水平。最后，本研究进一步分析了TBI患者血清Nrf2水平与各项临床指标的相关性，包括临床特征、炎症细胞因子及疾病严重程度。
【结果】本研究从GSE89866数据集中共筛选得到1795个DEGs，从GeneCards数据库获取98个焦亡相关基因。经交集分析后得到4个核心基因，选取NFE2L2开展后续临床研究。通过Kruskal-Wallis检验与Spearman相关性分析发现，重度TBI患者的血清Nrf2水平与格拉斯哥昏迷量表（GCS）评分呈负相关；反之，血清Nrf2水平与瞳孔参数、赫尔辛基CT评分、IL-1β及IL-18水平呈正相关。
【结论】综上，生物信息学分析显示NFE2L2在TBI的病理进程中发挥重要作用。临床研究表明，血清Nrf2水平升高与创伤严重程度及细胞因子水平密切相关。本研究推测，血清Nrf2或可作为临床实践中评估TBI的潜在生化标志物。