Sivelestat sodium (SIV), a neutrophil elastase inhibitor, is mainly used for the clinical treatment of acute respiratory distress syndrome (ARDS) or acute lung injury (ALI). However, studies investigating the effects of SIV treatment of ALI are limited. Therefore, this study investigated the potential molecular mechanism of the protective effects of SIV against ALI. Human pulmonary microvascular endothelial cells (HPMECs) were stimulated with tumor necrosis factor α (TNF-α), and male Sprague-Dawley rats were intratracheally injected with Klebsiella pneumoniae (KP) and treated with SIV, ML385, and anisomycin (ANI) to mimic the pathogenetic process of ALI in vitro and in vivo, respectively. The levels of inflammatory cytokines and indicators of oxidative stress were assessed in vitro and in vivo. The wet/dry (W/D) ratio of lung tissues, histopathological changes, inflammatory cells levels in bronchoalveolar lavage fluid (BALF), and survival rates of rats were analyzed. The JNK/NF-κB (p65) and Nrf2/HO-1 levels in the HPMECs and lung tissues were analyzed by western blot and immunofluorescence analyses. Administration of SIV reduced the inflammatory factors levels, intracellular reactive oxygen species (ROS) production, and malondialdehyde (MDA) levels and increased the levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in lung tissues. Meanwhile, SIV alleviated pathological injuries, decreased the W/D ratio, and inflammatory cell infiltration in lung tissue. In addition, SIV also inhibited the activation of JNK/NF-κB signaling pathway, promoted nuclear translocation of Nrf2, and upregulated the expression of heme oxygenase 1 (HO-1). However, ANI or ML385 significantly reversed these changes. SIV effectively attenuated the inflammatory response and oxidative stress. Its potential molecular mechanism was related to the JNK/NF-κB activation and Nrf2/HO-1 signaling pathway inhibition. This further deepened the understanding of the protective effects of SIV against ALI.
突发急性传染病是指在短时间内突然发生,重症和死亡比例高,早期识别困难,缺乏特异和有效的防治手段,易导致大规模暴发流行、构成突发公共卫生事件,造成或可能造成严重的社会、经济和政治影响,须采取紧急措施应对的传染病。随着经济贸易的全球化和人口流动的加剧,传染病呈现出全球性流行和蔓延的趋势,特別是一些突发急性传染病如鼠疫、高致病性禽流感、埃博拉、新冠肺炎等在世界各地的传播流行,预示着传染病已成为全球性危机。在当前新冠肺炎疫情防控形势下,国内外各级医疗机构应对突发急性传染病能力有了极大提高,建立了系统的防控流程和工作机制。院前转运作为救治的首要环节,对于传染病的控制至关重要,但我国幅员辽阔,各地医疗应急机构的建设水平不一,传染患者转运能力有一定的差别,提示我们在今后相当长的时间里传染病患者院前转运体系的进一步完善仍然是疾病预防控制工作的重点之一。在回顾分析2003年SARS、2005年四川人感染猪链球菌病、2009年甲型H1N1流感大流行、2013年人感染H7N9禽流感、2014年西非埃博拉疫情、2015年中东呼吸综合征和2019年至今的新冠肺炎防治经验的基础上,结合国内外针对突发急性传染病院前转运相关研究进展做一梳理。
Background: Reduning (RDN) is a common Chinese medicine preparation with antibacterial, antiinflammatory, antiviral and immunomodulatory effects in respiratory infectious diseases. Clinically, it is used in combination with antibiotics, but its synergistic effect and mechanism in treating severe pneumonia remain unclear. Methods: A rat model of severe pneumonia and an in vitro coculture model consisting of A549 and THP-1 cells were used to observe the synergistic effect of RDN on severe pneumonia. The inflammatory cytokines were tested by enzyme-linked immunosorbent assay (ELISA). The localization of Aryl hydrocarbon receptor (AhR) in A549 cells was observed by immunofluorescence, and the interaction of AhR and signal transducer and activator of transcription 3 (STAT3) proteins was observed by co-immunoprecipitation. AhR-Src tyrosine kinase (Src)-STAT3 pathway in rats and A549 cells were examined by Western Blot. Histopathological changes were observed by Hematoxylin-eosin (HE) staining, X-ray and survival rates were used to evaluate the effects of paclitaxel on severe pneumonia rats. Results: RDN regulation of Src-STAT3-interleukin 10 (IL-10) signaling pathway activation and macrophage polarization were mediated through the nuclear receptor AhR. The expression of AhR was significantly increased after RDN treatment, and this effect was accompanied by STAT3 expression increasing. Coimmunoprecipitation confirmed an interaction between AhR and STAT3 and upregulated IL-10 expression. Silencing AhR decreased Src, STAT3, and IL-10 expression. RDN activated AhR and increased Src, STAT3, and IL-10 expression. In addition, RDN regulated the polarization of macrophages RDN combined with cefmetazole sodium significantly reduced the pulmonary bacterial load, alleviated lung injury, and reduced o inflammatory factors expression, improving their survival. Conclusions: RDN can synergistically enhance the effect of cefmetazole sodium treatment in severe pneumonia, and the mechanism may involve increasing the expression level of IL-10 mediated through the AhR-Src-STAT3 pathway, driving the polarization of macrophages, and attenuating the cytokine storm to control inflammation in severe pneumonia.
Background:Acute liver injury can occur at any stage of sepsis and is an important sign of multiple organ dysfunction syndrome (MODS). Studies have shown that agmatine (AGM) can effectively improve liver injury caused by sepsis. However, due to the numerous metabolites and metabolic pathways of AGM in the human body, its mechanism in treating septic liver injury is unclear.Methods:In this study, a liver injury model of septic Sprague-Dawley rats was established by cecal ligation and perforation (CLP). After AGM treatment, transcriptomics combined with metabolomics was employed to analyze the gene expression levels and metabolite changes.Results:The results showed that AGM decreased the expression levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), procalcitonin (PCT), and inflammatory factors [interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β)] in the serum of septic rats. It also reduced liver inflammatory cell infiltration and abnormal lipid metabolism, and promoted the survival rate of septic rats. In addition, 17 differentially-expressed genes were identified by transcriptomics, mainly in arginine and proline metabolism, the arachidonic acid metabolism pathway, as well as the nuclear factor kappa B (NF-κB) and AMP-activated protein kinase (AMPK)-peroxisome proliferator-activated receptor α (PPARα) signal transduction pathways. Metabolomics analysis was carried out to study the potential liver metabolism spectrum changes induced by AGM treatment. The results showed significant changes in 26 metabolites in the rat liver samples, mainly involved in arginine and proline metabolism, arachidonic acid metabolism, linoleic acid metabolism, and fatty acid metabolism.Conclusions:The integrated transcriptomics and metabolomics analysis demonstrated that AGM improved septic liver injury by regulating lipid metabolism, and reduced the inflammatory reaction by affecting fatty acid metabolism, amino acid metabolism, and the arachidonic acid metabolism pathway. The integration of transcriptomics and metabolomics provides an effective means to elucidate AGM's therapeutic pathways and biomarkers.