Dysregulation of iron transport-related biomarkers in blood leukocytes is associated with poor prognosis of early trauma.

Objective: The early targeted and effective diagnosis and treatment of severe trauma are crucial for patients' outcomes. Blood leukocytes act as significant effectors during the initial inflammation and activation of innate immunity in trauma. This study aims to identify hub genes related to patients' prognosis in blood leukocytes at the early stages of trauma. Methods: The expression profiles of Gene Expression Omnibus (GEO) Series (GSE) 36809 and GSE11375 were downloaded from the GEO database. R software, GraphPad Prism 9.3.1 software, STRING database, and Cytoscape software were used to process the data and identify hub genes in blood leukocytes of early trauma. Results: Gene Ontology (GO) analysis showed that the differentially expressed genes (DEGs) of blood leukocytes at the early stages of trauma (0-4 h, 4-8 h, and 8-12 h) were mainly involved in neutrophil activation and neutrophil degranulation, neutrophil activation involved in immune response, neutrophil mediated immunity, lymphocyte differentiation, and cell killing. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the DEGs were mainly involved in Osteoclast differentiation and Hematopoietic cell lineage. Sixty-six down-regulated DEGs and 148 up-regulated DEGs were identified and 37 hub genes were confirmed by Molecular Complex Detection (MCODE) of Cytoscape. Among the hub genes, Lipocalin 2 (LCN2), Lactotransferrin (LTF), Olfactomedin 4 (OLFM4), Resistin (RETN), and Transcobalamin 1 (TCN1) were related to prognosis and connected with iron transport closely. LCN2 and LTF were involved in iron transport and had a moderate predictive value for the poor prognosis of trauma patients, and the AUC of LCN2 and LTF was 0.7777 and 0.7843, respectively. Conclusion: As iron transport-related hub genes in blood leukocytes, LCN2 and LTF can be used for prognostic prediction of early trauma.

ADAR1 Inhibits Macrophage Apoptosis and Alleviates Sepsis-induced Liver Injury Through miR-122/BCL2A1 Signaling.

Background and Aims: As sepsis progresses, immune cell apoptosis plays regulatory roles in the pathogenesis of immunosuppression and organ failure. We previously reported that adenosine deaminases acting on RNA-1 (ADAR1) reduced intestinal and splenic inflammatory damage during sepsis. However, the roles and mechanism of ADAR1 in sepsis-induced liver injury remain unclear. Methods: We performed transcriptome and single-cell RNA sequencing of peripheral blood mononuclear cells (PBMCs) from patients with sepsis to investigate the effects of ADAR1 on immune cell activities. We also employed a cecal ligation and puncture (CLP) sepsis mouse model to evaluate the roles of ADAR1 in sepsis-induced liver injury. Finally, we treated murine RAW 264.7 macrophages with lipopolysaccharide to explore the underlying ADAR1-mediated mechanisms in sepsis. Results: PBMCs from patients with sepsis had obvious apoptotic morphological features. Single-cell RNA sequencing indicated that apoptosis-related pathways were enriched in monocytes, with significantly elevated ADAR1 and BCL2A1 expression in severe sepsis. CLP-induced septic mice had aggravated liver injury and Kupffer cell apoptosis that were largely alleviated by ADAR1 overexpression. ADAR1 directly bound to pre-miR-122 to modulate miR-122 biosynthesis. miR-122 was an upstream regulator of BCL2A1. Furthermore, ADAR1 also reduced macrophage apoptosis in mice with CLP-induced sepsis through the miR-122/BCL2A1 signaling pathway and protected against sepsis-induced liver injury. Conclusions: The findings show that ADAR1 alleviates macrophage apoptosis and sepsis-induced liver damage through the miR-122/BCL2A1 signaling pathway. The study provides novel insights into the development of therapeutic interventions in sepsis.

HIF-1α promotes the expression of syndecan-1 and inhibits the NLRP3 inflammasome pathway in vascular endothelial cells under hemorrhagic shock.

Hemorrhagic shock (HS) is a global life-threatening matter that causes massive mortality annually worldwide. Syndecan-1 (SDC1) is an important predictor and evaluation index for HS, but its mechanism involved in the HS development remain unclear. HS mice model and human umbilical vein endothelial cells (HUVECs) under hypoxia were applied to explore the relationship of SDC1 with HIF-1α and NLRP3 inflammasome in vascular ECs under HS. Transcriptome sequencing of isolated vascular ECs were conduct to search for hub genes. Dual luciferase assay was adopted to prove the binding effects of the HIF-1α on SDC1 promoter in HUVECs. Molecular expression was evaluated through routine experiments. Here, HS led to aggravated lung injury and inflammatory response with the shedding of SDC1 on the lung vascular ECs in mice. Circulatory SDC1 and proinflammatory cytokines were significantly increased after HS. HIF-1α and IL-1ß were identified as hub genes in vascular ECs of HS mice. Meanwhile, HIF-1α-mediaed hypoxia and IL-1ß-involved NLRP3 inflammasome pathways were activated following HS. The transcriptional factor HIF-1α promoted the expression of SDC1 through binding to the SDC1 promoter. SDC1 had an inhibitory effect on the NLRP3 inflammasome activity. An exogenous increase of HIF-1α upregulated SDC1 and restrained the activation of the NLRP3 inflammasome under hypoxia, while further interference of SDC1 weakened this effect. Hence, SDC1 is an intermediate connecting HIF-1α and NLRP3 inflammasome in the vascular ECs under hypoxia. HIF-1α promotes the expression of SDC1 and inhibits the NLRP3 inflammasome pathway in vascular ECs under HS.

HBO Alleviates Neural Stem Cell Pyroptosis via lncRNA-H19/miR-423-5p/NLRP3 Axis and Improves Neurogenesis after Oxygen Glucose Deprivation.

Due to the limited neurogenesis capacity, there has been a big challenge in better recovery from neurological dysfunction caused by stroke for a long time. Neural stem cell (NSC) programmed death is one of the unfavorable factors for neural regeneration after stroke. The types of death such as apoptosis and necroptosis have been deeply investigated while the pyroptosis of NSCs is not quite understood. Although it is well accepted that hyperbaric oxygen (HBO) alleviates the oxygen-glucose deprivation (OGD) injury after stroke and reduces programmed death of NSCs, whether NSC pyroptosis is involved in this process is still unknown. Therefore, this study is aimed at studying the potential effect of HBO treatment on NSC pyroptosis following OGD exposure, as well as its influence on NSC proliferation and differentiation in vitro. The results revealed that OGD increased NOD-like receptor protein 3 (NLRP3) expression to induce the pyroptotic death of NSCs, which was rescued by HBO treatment. And the upregulated lncRNA-H19 functioned as a molecular sponge of miR-423-5p to target NLRP3 for NSC pyroptosis following OGD. Most importantly, it was confirmed that HBO exerted protection of NSCs against pyroptosis by inhibiting lncRNA-H19/miR-423-5p/NLRP3 axis. Moreover, HBO restraint of lncRNA-H19-associated pyroptosis benefited the proliferation and neuronal differentiation of NSCs. It was concluded that HBO attenuated NSC pyroptosis via lncRNA-H19/miR-423-5p/NLRP3 axis and enhanced neurogenesis following OGD. The findings provide new insight into NSC programmed death and enlighten therapeutic strategy after stroke.

CD226 deficiency promotes glutaminolysis and alleviates mitochondria damage in vascular endothelial cells under hemorrhagic shock.

Hemorrhagic shock (HS) is common in clinical emergencies, leading to millions of deaths each year globally. CD226 is a costimulatory adhesion molecule expressed on both immune cells and endothelial cells (ECs) to regulate their metabolic activity and function. As endothelial dysfunction occurs after HS, the roles CD226 plays in vascular EC metabolism were investigated. CD226fl/fl Tekcre mice were adopted to achieve vascular EC-specific knockout of CD226, and subjected to HS modelling. Serum levels of crucial intermediate metabolites were evaluated through liquid chromatography-mass spectrometry analysis. Human umbilical vein ECs (HUVECs) were used to study the effects of CD226 under hypoxia in vitro. Seahorse analysis evaluated the cellular glycolysis and mitochondria bioenergetics. Results showed that CD226 deficiency in vascular ECs alleviated HS-induced intestinal damage and inflammatory response in mice. Animal studies indicated an improved energy metabolism when CD226 was knocked out in ECs after HS, as evidenced by enhanced glutamine-glutamate metabolism and decreased lactic acid levels. Glut-1 was upregulated in mouse vascular ECs after HS and HUVECs under hypoxia, combined with decreased CD226. Moreover, HUVECs with CD226 knockdown exhibited relieved mitochondrial damage and early apoptosis under hypoxia, whereas CD226 overexpression showed opposite effects. Seahorse analysis showed that downregulated CD226 significantly increased mitochondrial ATP production and glucose uptake in HUVECs under hypoxia. Additionally, Erk/PHD2 signaling-mediated HIF-1α/Glut-1 and HIF-2α/ASCT2 pathways were involved in CD226 regulation on HUVEC glutaminolysis after hypoxia. Hence, CD226 deficiency promotes bypass energy supply to vascular ECs under ischemic or hypoxic stress, to ameliorate the stress-mediated metabolic disturbance.

[IL-6, IL-1ß, and IL-10 levels in peripheral blood as indicators for early identification of gram-positive and gram-negative sepsis].

Objective To find out indicators for rapid identification of Gram-positive (G+) and Gram-negative (G-) bacteria through transcriptome sequencing of peripheral blood mononuclear cells (PBMCs) and serum liquid-phase chip technology in early sepsis. Methods 35 eligible cases out of 182 sepsis patients in the emergency intensive care unit (EICU) were selected for retrospective analysis. They were divided into G+ group (12 cases) and G- group (23 cases) based on their blood culture results. General characteristics like patients' age, gender, sequential organ failure assessment (SOFA) scores, etc. and other laboratory indexes such as blood routine, IL-6, CRP, procalcitonin(PCT)of these two groups were analyzed. PBMCs were isolated through single density gradient centrifugation. Total RNA was extracted for transcriptome sequencing to find out differential genes. Serum liquid-phase chip technology was performed to detect serum granulocyte colony stimulating factor (G-CSF), granulocyte-macrophage colony stimulating factor (GM-CSF), IFN-γ, IL-1ß, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, IL-17, monocytes chemotactic protein 1 (MCP-1), tumor necrosis factor alpha (TNF-α) in two groups. Receiver operating characteristic (ROC) curve was drawn using bacteria types as a dependent variable and selected cytokines as test variables, to analyze the correlation between selected biomarkers and bacteria type. Results No significant difference in general characteristics, CRP, and PCT were found between the G+ and G- group. The serum level of IL-6 in G+ group was lower than that in the G- group. Transcriptome sequencing results revealed 30 immune-related genes that were differentially expressed in the PBMCs of two groups. Compared to the G+ group, the serum levels of IL-6 and IL-1ß in G- group significantly increased, while serum IL-10 was reduced. ROC curve analysis indicated that serum IL-6, IL-1ß, and IL-10 levels could identify the G- and G+ bacteria types. The combined diagnosis using these three indicators is highly applicable in distinguishing G- and G+ bacteria. Conclusion IL-6, IL-1ß and IL-10 levels can be used as indicators for early identification of sepsis induced by G+ or G- bacteria.

Splenectomy improves liver fibrosis via tumor necrosis factor superfamily 14 (LIGHT) through the JNK/TGF-ß1 signaling pathway.

Splenectomy has been reported to improve liver fibrosis in patients with cirrhosis and hypersplenism. However, the mechanisms remain unclear. Tumor necrosis factor superfamily 14 (TNFSF14; also known as LIGHT) is highly expressed in the context of fibrosis and promotes disease progression in patients with fibrotic diseases such as pulmonary and skin fibrosis. Here, we determined whether splenectomy controls the production of LIGHT to improve liver fibrosis. Splenectomy reduced serum LIGHT levels in cirrhotic patients with hypersplenism and a ConA-induced liver fibrosis mouse model. Blocking LIGHT resulted in the downregulation of TGF-ß1 in RAW264.7 cells. LIGHT treatment of RAW264.7 and JS1 cells in coculture regulated transforming growth factor-ß1 (TGF-ß1) expression through the activation of JNK signaling. Small interfering RNA-mediated silencing of lymphotoxin ß receptor (LTßR) in macrophages resulted in pronounced decreases in the levels of fibrosis and αSMA in JS1 cells. These results indicated that LIGHT bound to LTßR and drove liver fibrosis in vitro. Blocking TGF-ß1 abolished the effect of LIGHT in vitro. Furthermore, the administration of recombinant murine LIGHT protein-induced liver fibrosis with splenectomy, while blocking LIGHT without splenectomy improved liver fibrosis in vivo, revealing that the decrease in fibrosis following splenectomy was directly related to reduced levels of LIGHT. Thus, high levels of LIGHT derived from the spleen and hepatic macrophages activate JNK signaling and lead to increased TGF-ß1 production in hepatic macrophages. Splenectomy attenuates liver fibrosis by decreasing the expression of LIGHT.

[The conditional knockout of CD226 gene reduces acute lung injury in mice with hemorrhagic shock].

Objective To investigate the effects on acute lung injury (ALI) of CD226 conditional knockout (CD226 CKO) in vascular endothelial cells were investigated in mice with hemorrhagic shock (HS) and its mechanism. Methods Male wild type (WT) and CD226 CKO mice were randomly divided into sham and HS groups: in the sham group, a heart puncture was performed but blood was not drawn; in the HS group, the heart was punctured and 30% of the total blood volume was drawn. To assess lung injury, lung lesions were observed by HE staining. Immunofluorescence histochemical staining was used to detect the expression and distribution of CD31, CD226 in lung tissue and CD3 and CD226 in spleen. In addition, a RNA interering (RNAi) was used to knockdown CD226 in human umbilical vein endothelial cells and a hypoxia model was established. Protein expression of Bcl2 in lung tissue and vascular endothelial cells was detected by Western blotting. Early apoptosis was detected by JC-1 mitochondrial membrane potential staining. Results In the HS groups, CD226 CKO mice showed significantly less ALI than WT mice, and the protein expression of Bcl2 in their lung tissues increased. Furthermore, in vitro cytological models revealed that protein expression of Bcl2 increased and apoptosis decreased in the siCD226 group relative to the siNC group under hypoxia. Conclusion CD226 CKO in vascular endothelial cells reduces ALI in mice with HS, and this effect is associated with increased expression of Bcl2 and decreased apoptosis.

Ulinastatin and/or thymosin α1 for severe sepsis: A systematic review and meta-analysis.

OBJECTIVE: Ulinastatin (UTI) and thymosin α1 (Tα1) have been investigated for their immunoregulatory properties in patients with severe sepsis. However, it is unclear whether immunomodulatory therapy using UTI combined with Tα1 (UCT), UTI alone (UA), or Tα1 alone (TA) improves the disease outcome. The objective of this study was to analyze the effectiveness of UCT, UA, and TA for the treatment of severe sepsis. METHODS: PubMed, EMBASE, and Cochrane Library databases were investigated from inception to September 2015. Randomized controlled trials (RCTs) examining the treatment of patients with severe sepsis by UCT, UA, and TA were defined as eligible. Data were analyzed using Review Manager 5.3, and the RCTs were evaluated by the Cochrane Handbook 5.1.0. The quality of the evidence was evaluated according to the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE). RESULTS: Ten articles and 12 studies were included in this systematic review and meta-analysis. The primary outcome measures indicated that UCT was associated with significantly lower 28-day mortality (risk ratio [RR], 0.67; 95% confidence interval [CI], 0.57-0.80; p < 0.00001; n = 915; GRADE rating, moderate) and 90-day mortality (RR, 0.75; 95% CI, 0.61-0.93; p = 0.009; n = 547; GRADE rating, moderate); UA was associated with no significant difference in the 28-day mortality (RR, 0.60; 95% CI, 0.30-1.20; p = 0.15; n = 182; GRADE rating, low), and there was no report on 90-day mortality; TA was associated with significantly lower 28-day mortality (RR, 0.72; 95% CI, 0.55-0.93; p = 0.01; n = 494; GRADE rating, low), but there was no significant difference in the 90-day mortality (RR, 0.84; 95% CI, 0.54-1.31; p = 0.45; n = 91; GRADE rating, very low). In the secondary outcome measures, there was obvious heterogeneity in the length of the intensive care unit stay and that of the mechanical ventilation, length of the antibiotics and vasopressor use, and 28-day Acute Physiology and Chronic Health Evaluation II (APACHE II) scores. CONCLUSION: Treatment of severe sepsis with UCT reduced both the 28-day and the 90-day mortality, whereas treatment with TA reduced only the 28-day mortality. The effects of UCT, UA, and TA on intensive care unit stay, mechanical ventilation, antibiotics and vasopressor use, and 28-day APACHE II scores of septic patients are still unclear. Additional high-quality RCTs are needed to define clearly the guidelines for the treatment of severe sepsis. LEVEL OF EVIDENCE: Systematic review, level IV.