Hao Yuewei, Wang Zheng, Wang Xinfang, Zhan Wenming, Wu Dianshui
Department of Emergency, Shandong Second Provincial General Hospital, Jinan, China.
Prehospital Emergency, Shandong Second Provincial General Hospital, Jinan, China.
J Thorac Dis. 2021 Aug;13(8):5042-5054. doi: 10.21037/jtd-21-948.
Acute lung injury (ALI) induced by sepsis is a common cause of death in clinical practice, and there remains a lack of clinical effective treatment. Cecal ligation and puncture (CLP) is a classic animal model of sepsis, which can induce ALI. Studies have shown that in the lung injury cell model, OGDH (oxoglutarate dehydrogenase) transcription is up-regulated, which is a potential therapeutic target for acute pneumonia. The purpose of this study was to confirm the effects of OGDH on lung injury and inflammation in animal and cell models, and to explore its mechanism.
By analyzing the GSE16650 gene set, the upregulated OGDH gene was detected in the lung injury cell model. In a sepsis animal model established by CLP and a lung injury cell model, RT-PCR, immunohistochemistry, WB, and other techniques were used to verify the upregulation of OGDH expression, which was then was down-regulated with shRNA to confirm its relationship with ALI. Further, ELISA, RT-PCR, and WB were used to detect the effect of OGDH on the expression of pro-inflammatory factors including IL-1β, IL-6, IL-18, and TNF-α. The downstream pathway of OGDH was predicted using KEGG and GSEA tools and verified by WB and immunofluorescence.
The results showed OGDH was highly expressed in a lung injury cell model and the lung tissue of ALI mice induced by CLP, and downregulation of OGDH alleviated sepsis induced ALI. In animal models and cell models, the expression of OGDH was positively correlated with the expression of pro-inflammatory factors. OGDH may act through the MAPK pathway.
Under the pathological condition of sepsis, OGDH amplifies the inflammatory response through the MAPK pathway, releases pro-inflammatory factors, and induces ALI.
脓毒症诱导的急性肺损伤（ALI）是临床实践中常见的死亡原因，目前仍缺乏临床有效的治疗方法。盲肠结扎穿孔术（CLP）是一种经典的脓毒症动物模型，可诱发ALI。研究表明，在肺损伤细胞模型中，氧代戊二酸脱氢酶（OGDH）转录上调，这是急性肺炎的一个潜在治疗靶点。本研究旨在证实OGDH在动物和细胞模型中对肺损伤和炎症的影响，并探讨其机制。
通过分析GSE16650基因集，在肺损伤细胞模型中检测到上调的OGDH基因。在通过CLP建立的脓毒症动物模型和肺损伤细胞模型中，采用逆转录-聚合酶链反应（RT-PCR）、免疫组织化学、蛋白质免疫印迹（WB）等技术验证OGDH表达上调，然后用短发夹RNA（shRNA）下调其表达以证实其与ALI的关系。此外，采用酶联免疫吸附测定（ELISA）、RT-PCR和WB检测OGDH对包括白细胞介素-1β（IL-1β）、白细胞介素-6（IL-6）、白细胞介素-18（IL-18）和肿瘤坏死因子-α（TNF-α）在内的促炎因子表达的影响。使用京都基因与基因组百科全书（KEGG）和基因集富集分析（GSEA）工具预测OGDH的下游通路，并通过WB和免疫荧光进行验证。
结果显示，OGDH在肺损伤细胞模型和CLP诱导的ALI小鼠肺组织中高表达，下调OGDH可减轻脓毒症诱导的ALI。在动物模型和细胞模型中，OGDH的表达与促炎因子的表达呈正相关。OGDH可能通过丝裂原活化蛋白激酶（MAPK）途径发挥作用。
在脓毒症的病理条件下，OGDH通过MAPK途径放大炎症反应，释放促炎因子，诱导ALI。
