Project description:Inflammation resolution is critical for sepsis induced acute lung injury (ALI) recovery. Interleukin-36 receptor (IL-36R) is a potent anti-inflammatory factor. However, its role in ALI resolution remains unclear. We investigated the effects of IL-36R during the ALI resolution process in a murine cecal ligation and puncture (CLP)-induced ALI model. Knockout IL-36R signaling aggravates CLP-induced lung injury, as manifested by elevated bacterial load and increased neutrophils recruitment to the lung. Thereafter, we used IL-36R knockout mice to discern the source cell of IL-36R during ALI. We found that IL-36R is predominantly generated by epithelial cells during the ALI process. Furthermore, we sorted lung epithelial cells on the ALI process. IL-36R-specific loss in epithelial cells leads to apoptosis through NF-κB pathway. Together, our findings identify molecules that are likely involved in sepsis induced lung injury that may inform biomarker and therapeutic development.
Project description:We have previously demonstrated that pre-B-cell colony enhancing factor (PBEF) ais a biomarker in sepsis and sepsis-induced acute lung injury (ALI) with genetic variants conferring ALI susceptibility118. In the current study, we explored the mechanistic participation of PBEF in ALI and ventilator-induced associated lung injury (VIALI). Initial in vitro studies and demonstrated rhPBEF aas a direct rat neutrophil chemotactic factor in vitro producing marked in vivo increases in BAL leukocytes (PMNs) in vivo following (intratracheal injection (,IT) in C57B6 mice. These latter changes were accompanied by increased BAL levels of the PMN chemoattractants (, KC and MIP2), and modest changes in lung vascular and but were not associated with significant increasesin alveolar permeability. We next explored the potential synergism between rhPBEF administration (IT) and a mechanical ventilation model of modest VILI lung injury (4 hours, 30 ml/kg tidal volume). We and observed dramatic synergistic increases in BAL PMNs, and both BAL protein and cytokine levels (IL-6, TNF-?, KC). Gene expression profiling Microarray analysis further supported a major role for PBEF in the induction of gene modules associated with ALI and VALI (NFkB pathway, leukocyte extravasation, apoptosis, toll receptor signaling). Finally, we exposed wild type and heterozygous PBEF+/- mice (targeted deletion of a single PBEF allele deletion) to a model of severe VILImechanical ventilation-induced lung injury (4 hours, 40 ml/kg tidal volume). PBEF+/- mice were significantly protected from VIALI-associated increases in BAL protein and BAL IL-6 levels and exhibited significantly reduced expression of ALI-associated gene expression modules. Together, these results indicate that PBEF is a key inflammatory mediator intimately involved in both the development and severity of ventilator-induced ALI. Experiment Overall Design: animals were treated by PBS, rhPBEF (IT administration), VILI (4 hours, 30 ml/kg tidal volume), or both.
Project description:The Acute Respiratory Distress Syndrome (ARDS)/Acute Lung Injury (ALI) was described 30 years ago, yet the interaction between specific sets of genes involved in this syndrome remains incompletely understood. Experiment Overall Design: 13 patients with ALI + sepsis and 21 patients with sepsis alone were recruited from the Medical Intensive Care Unit of the University of Pittsburgh Medical Center between February 2005 and June 2007. Whole blood was obtained from each patient within 48 hours of admission, and RNA was extracted for gene expression profiling, and comparison analysis.
Project description:Although respiratory distress is a common complication of severe malaria, little is known about the underlying molecular basis of lung dysfunction. Animal models have provided powerful insights into the pathogenesis of severe malaria syndromes such as cerebral malaria; however, no model of malaria-induced lung injury has been definitively established. This work used bronchoalveolar lavage (BAL), histopathology and gene expression analysis to examine the development of acute lung injury (ALI) in mice infected with Plasmodium berghei ANKA (PbA). BAL fluid of PbA-infected C57BL/6 mice revealed a significant increase in IgM and total protein prior to the development of cerebral malaria (CM), indicating disruption of the alveolar-capillary membrane barrier – the physiological hallmark of acute lung injury (ALI). In contrast to sepsis-induced ALI, BAL fluid cell counts remained constant with no infiltration of neutrophils. Histopathology showed septal inflammation without cellular transmigration into the alveolar spaces. Microarray analysis comparing malaria-induced ALI with sepsis-induced ALI identified several common gene ontology groups characterizing ALI in these models, including defense and immune response. Severity of malaria-induced ALI varied in a panel of inbred mouse strains, and development of ALI correlated with peripheral parasite burden but not CM susceptibility. CD36-/- mice, which have decreased parasite lung sequestration, were relatively protected from ALI. In summary, parasite burden and CD36-mediated sequestration in the lung are primary determinants of ALI in experimental murine malaria. Furthermore, differential susceptibility of mouse strains to malaria-induced ALI and CM indicate that distinct genetic determinants likely regulate susceptibility to these two important causes of malaria-associated morbidity and mortality. Keywords: Time course
Project description:We have previously demonstrated that pre-B-cell colony enhancing factor (PBEF) ais a biomarker in sepsis and sepsis-induced acute lung injury (ALI) with genetic variants conferring ALI susceptibility118. In the current study, we explored the mechanistic participation of PBEF in ALI and ventilator-induced associated lung injury (VIALI). Initial in vitro studies and demonstrated rhPBEF aas a direct rat neutrophil chemotactic factor in vitro producing marked in vivo increases in BAL leukocytes (PMNs) in vivo following (intratracheal injection (,IT) in C57B6 mice. These latter changes were accompanied by increased BAL levels of the PMN chemoattractants (, KC and MIP2), and modest changes in lung vascular and but were not associated with significant increasesin alveolar permeability. We next explored the potential synergism between rhPBEF administration (IT) and a mechanical ventilation model of modest VILI lung injury (4 hours, 30 ml/kg tidal volume). We and observed dramatic synergistic increases in BAL PMNs, and both BAL protein and cytokine levels (IL-6, TNF-?, KC). Gene expression profiling Microarray analysis further supported a major role for PBEF in the induction of gene modules associated with ALI and VALI (NFkB pathway, leukocyte extravasation, apoptosis, toll receptor signaling). Finally, we exposed wild type and heterozygous PBEF+/- mice (targeted deletion of a single PBEF allele deletion) to a model of severe VILImechanical ventilation-induced lung injury (4 hours, 40 ml/kg tidal volume). PBEF+/- mice were significantly protected from VIALI-associated increases in BAL protein and BAL IL-6 levels and exhibited significantly reduced expression of ALI-associated gene expression modules. Together, these results indicate that PBEF is a key inflammatory mediator intimately involved in both the development and severity of ventilator-induced ALI. We used microarrays to detail the global programme of gene expression induced by rhPBEF treatment and VALI. Experiment Overall Design: animals were treated by PBS, rhPBEF (IT administration), VILI (4 hours, 30 ml/kg tidal volume), or both.
Project description:Acute lung injury (ALI) is associated with a high mortality rate; however, the underlying molecular mechanisms are poorly understood. The purpose of this study was to investigate the expression profile and related networks of long noncoding RNAs (lncRNAs), microRNAs (miRNAs), and mRNAs in lung tissue exosomes obtained from sepsis-induced ALI. A mouse model of sepsis was established using the cecal ligation and puncture method. RNA sequencing was performed using lung tissue exosomes obtained from mice in the sham and CLP groups. Hematoxylin-eosin staining, western blotting, immunofluorescence, quantitative real-time polymerase chain reaction, and nanoparticle tracking analysis were performed to identify relevant phenotypes, and bioinformatic algorithms were used to evaluate competitive endogenous RNA (ceRNA) networks.Thirty lncRNA-miRNA-mRNA interactions were identified, including two upregulated lncRNAs, 30 upregulated miRNAs, and two downregulated miRNAs. Based on the expression levels of DEmRNAs, DELncRNAs, and DEmiRNAs, 30 ceRNA networks were constructed. This study revealed, for the first time, biomarkers of lung tissue exosome RNA and the related networks of lncRNA in sepsis-induced ALI. We revealed a novel molecular mechanism of sepsis-induced ALI, which may support the diagnosis and treatment of sepsis-induced ALI.
Project description:Acute lung injury (ALI) is associated with a high mortality rate; however, the underlying molecular mechanisms are poorly understood. The purpose of this study was to investigate the expression profile and related networks of long noncoding RNAs (lncRNAs), microRNAs (miRNAs), and mRNAs in lung tissue exosomes obtained from sepsis-induced ALI. A mouse model of sepsis was established using the cecal ligation and puncture method. RNA sequencing was performed using lung tissue exosomes obtained from mice in the sham and CLP groups. Hematoxylin-eosin staining, western blotting, immunofluorescence, quantitative real-time polymerase chain reaction, and nanoparticle tracking analysis were performed to identify relevant phenotypes, and bioinformatic algorithms were used to evaluate competitive endogenous RNA (ceRNA) networks.Thirty lncRNA-miRNA-mRNA interactions were identified, including two upregulated lncRNAs, 30 upregulated miRNAs, and two downregulated miRNAs. Based on the expression levels of DEmRNAs, DELncRNAs, and DEmiRNAs, 30 ceRNA networks were constructed. This study revealed, for the first time, biomarkers of lung tissue exosome RNA and the related networks of lncRNA in sepsis-induced ALI. We revealed a novel molecular mechanism of sepsis-induced ALI, which may support the diagnosis and treatment of sepsis-induced ALI.
Project description:Acute Lung Injury (ALI) can cause Acute Respiratory Distress Syndrome (ARDS), a lethal condition with limited treatment options and currently a common global cause of death due to COVID-19-induced ALI. ARDS secondary to Transfusion-Related Acute Lung Injury (TRALI) has been recapitulated pre-clinically by anti-MHC-I antibody administration to LPS-primed mice. In this model, we demonstrated that inhibitors of PTP1B, a protein tyrosine phosphatase that regulates signaling pathways of fundamental importance to homeostasis and inflammation, prevented lung injury and increased survival. Treatment with PTP1B inhibitors attenuated the aberrant neutrophil function that drives ALI, and was associated with release of myeloperoxidase, suppression of Neutrophil Extracellular Trap (NET) formation, and inhibition of neutrophil migration. Mechanistically, reduced signaling through the CXCR4 chemokine receptor, particularly to the activation of mTOR, was essential for these effects, linking PTP1B in hibition to promoting an aged neutrophil phenotype. Considering dysregulated activation of neutrophils is implicated in sepsis and can cause collateral tissue damage, we demonstrated also that PTP1B inhibitors improved survival and ameliorated lung injury in the LPS-induced sepsis model. Our data highlight PTP1B inhibition for prevention of TRALI and ARDS from multiple etiologies.
Project description:Sepsis-induced acute lung injury (ALI) is a severe clinical condition with a high mortality rate. Tangeretin, widely found in citrus fruits, has been reported to exert antioxidant and anti-inflammatory properties. However, whether Tangeretin protects against sepsis-induced ALI and the potential mechanisms remain unclear.We established ALI model via intraperitoneally injected with 5 mg/kg lipopolysaccharides (LPS) for 12 h. Tangeretin was applied intraperitoneally 30 min before LPS treatment. The lung tissue samples from both the LPS and LPS + TAN groups were subjected to RNA sequencing analysis, conducted by OE Biotech Co., Ltd. (Shanghai, China). We performed differential gene expression analysis using RNA-seq data between LPS and LPS/Tangeretin group.GSEA analysis between LPS and LPS/Tangeretin group showed that IL6_JAK_STAT3_SIGNALING, INFLAMMATORY_RESPONSE, TNFA_SIGNALING_VIA_NFKB were significantly enriched (Fig.3C-E). These results identified the anti-inflammatory effect of Tangeretin against sepsis-induced ALI.
Project description:Sepsis-induced acute lung injury (ALI) is prevalent in septic patients and has a high mortality rate. Considering ALI’s close link to sepsis, we used a Pseudomonas aeruginosa (PA) pneumonia-induced sepsis mouse model to investigate alveolar microenvironment alterations and lung injury post-sepsis. Peptidyl arginine deiminase (PADI) 2 and PADI4 are highly expressed in immune cells, and play substantial roles in the immune response to sepsis, but their specific functions remain unclear.We employed single-cell RNA sequencing (scRNA-seq) technology to map immune cell populations in bronchoalveolar lavage fluid (BALF) cells from Wild type (WT) and Padi2 and Padi4 double knock-out (DKO)mice in PA pneumonia-induced sepsis and sham conditions.