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Comparison of platelet aggregation percentage, serum thromboxane B2, Nox2 activity, and serum HBA among healthy controls, patients with sepsis, and those with septic shock. Legend: ∗p<0.001 among the 3 groups (one-way ANOVA for k samples). HBA = hydrogen peroxide breakdown activity; IQR = interquartile ranges; TBx2 = thromboxane B2.
Source publication
Background:
Although preclinical studies highlighted the potential role of NADPH oxidase (NOX) in sepsis, only few studies evaluated the oxidative stress in patients with sepsis and septic shock. The objective of the study is to appraise the oxidative stress status and platelet function in patients with sepsis and septic shock compared to healthy...
Citations
... groups. The deceased group showed a tendency towards higher levels of soluble NOX2-derived peptides compared to the survival group, which was consistent with the results of our study (33). Additionally, Joseph LC et al. found that NOX2 increases oxidative stress, leading to mitochondrial dysfunction and septic myocardial injury (34). ...
Objective
Sepsis related injury has gradually become the main cause of death in non-cardiac patients in intensive care units, but the underlying pathological and physiological mechanisms remain unclear. The Third International Consensus Definitions for Sepsis and Septic Shock (SEPSIS-3) definition emphasized organ dysfunction caused by infection. Neutrophil extracellular traps (NETs) can cause inflammation and have key roles in sepsis organ failure; however, the role of NETs-related genes in sepsis is unknown. Here, we sought to identify key NETs-related genes associate with sepsis.
Methods
Datasets GSE65682 and GSE145227, including data from 770 patients with sepsis and 54 healthy controls, were downloaded from the GEO database and split into training and validation sets. Differentially expressed genes (DEGs) were identified and weighted gene co-expression network analysis (WGCNA) performed. A machine learning approach was applied to identify key genes, which were used to construct functional networks. Key genes associated with diagnosis and survival of sepsis were screened out. Finally, mouse and human blood samples were collected for RT-qPCR verification and flow cytometry analysis. Multiple organs injury, apoptosis and NETs expression were measured to evaluated effects of sulforaphane (SFN).
Results
Analysis of the obtained DEGs and WGCNA screened a total of 3396 genes in 3 modules, and intersection of the results of both analyses with 69 NETs-related genes, screened out seven genes (S100A12, SLC22A4, FCAR, CYBB, PADI4, DNASE1, MMP9) using machine learning algorithms. Of these, CYBB and FCAR were independent predictors of poor survival in patients with sepsis. Administration of SFN significantly alleviated murine lung NETs expression and injury, accompanied by whole blood CYBB mRNA level.
Conclusion
CYBB and FCAR may be reliable biomarkers of survival in patients with sepsis, as well as potential targets for sepsis treatment. SFN significantly alleviated NETs-related organs injury, suggesting the therapeutic potential by targeting CYBB in the future.
... [23][24][25] The results of the present study showed that the positive expression rate of CD63 in platelets in the septic shock group was significantly higher than that in the normal control group, and platelet activation increased with the risk of septic shock patients, indicating that platelet activation is an important pathological basis of sepsis. 26 It is suggested that the positive expression rate of CD63 in platelets may be used as a laboratory indicator to predict the progression of septic shock. The possible mechanisms of increased platelet activity in patients with septic shock are as follows: increased capillary permeability and endothelial cell injury in patients with septic shock, on the basis of which a large number of platelet activating factors are activated; as the disease progresses, platelet activating factors interact with other pro-inflammatory cytokines, inflammatory mediators, and vasoactive substances through positive and negative feedback regulation to form a vicious cycle and further activate platelets. ...
Background
The molecular mechanism of septic shock is unknown. We studied the pathogenesis of septic shock and provide a novel strategy for treating and improving the prognosis of septic shock.
Methods
Gluten-Sensitive Enteropathy (GSE) 131761, GSE119217, GSE26378 datasets were downloaded from the Gene Expression Omnibus (GEO) database. The three datasets included 204 septic shock samples and 48 normal samples. The R packages “affy” and “limma” were employed to identify the differently expressed genes (DEGs) between septic shock and normal samples. Weighted gene co-expression network analysis (WGCNA) was performed to search for modules that play an important role in septic shock. Functional annotation of DEGs and construction and analysis of hub genes were used to explore the pathomechanism of septic shock. The receiver operating characteristic (ROC) curves were obtained using MedCalc software. The drug molecules that could regulate hub genes associated with septic shock were searched for in the CMap database. An animal model of septic shock was constructed to analyze the role of these hub genes.
Results
The merged series contained 321 up-regulated and 255 down-regulated genes. WGCNA showed the brown module had the highest correlation with the status of septic shock. GO and KEGG enrichment analysis results of the brown module genes showed they were mainly enriched in “leukocyte differentiation”, “Ras-proximate-1 (Rap1) signaling pathway”, and “cytokine–cytokine receptor interaction”. Through construction and analysis of a protein–protein interaction (PPI) network, cluster of differentiation 63 (CD63) and complement component 3a receptor 1 (C3AR1) were identified as hub genes of septic shock. The area under curve (AUC) of C3AR1 for the septic shock is 0.772 (P<0.001), and the AUC of CD63 for the septic shock is 0.871 (P<0.001). Small molecule drugs were filtered by the number of instances (n>3) and P-values <0.05, including “monensin”, “verteporfin”, “ikarugamycin”, “tetrahydroalstonine”, “cefamandole”, “etoposide”. In the animal model, the relative expression levels of interleukin-6 (IL-6), Tumor Necrosis Factor-α (TNF-α), and lactic acid were significantly higher in the septic shock group compared with the control group. Results of Real Time Quantitative PCR (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA) analysis for CD63 and C3AR1 showed that their relative expression levels were significantly lower in the septic shock group compared with the control group (P<0.05).
Conclusion
CD63 and C3AR1 are significant hub genes of septic shock and may represent potential molecular targets for future studies of septic shock.
... Another pathway includes the interaction between endothelial cells and platelets representing endothelial cells that leads to sepsis. Platelet consumption in microcirculation makes thrombocytopenia a strong mortality predictor [4][5][6]. Toll-like receptors (TLRs) TLR2 and TLR4 present on the platelet surface and activate in sepsis by recognizing pathogen-specific ligands activating signal transduction downstream cascade [7]. ...
Ischemic bowel disease is a life-threatening condition, and mortality will worsen if the patient presented in septic shock. Several factors affect the outcome of this disease. Recent data suggests, however, that patients who develop shock secondary to ischemic bowel and have a history of taking anti-platelet medications within two weeks of presentation may have a higher chance of survival when compared to a patient who did not. The study aims to determine the impaction of prophylactic anti-platelet (Aspirin and clopidogrel) administration in improving outcomes among patients who present with septic shock secondary to ischemic bowel. It was a retrospective cohort study conducted in all hospitals located in Winnipeg, Manitoba, Canada, from July 1989 until June 2007. 133 patients were presented in septic shock secondary to ischemic bowel. The primary outcome was survival to hospital discharge. Twenty-seven patients had a history of taking antiplatelet agent within two weeks before presentation, and 106 patients did not. Out of 27 of the patients who took antiplatelet agent, 15 patients survived, and 12 patients died with a mortality rate of 44%. Four patients had a history of taking dual anti-platelets (Aspirin and Clopidogrel) and all of them survived. Among the 106 patients who did not have a history of taking antiplatelet agent, only 19 patients survived with a mortality rate of 82%. This study investigates the impact of anti-platelet therapy in patients presenting to the emergency department and intensive care unit with and without prior use of antiplatelet therapy. Before presenting with septic shock secondary to ischemic bowel, patients who were on anti-platelet had a better chance to survive and got discharged home.
... This intricated process can be monitored in vivo by dosing sNOX2-dp, a soluble peptide released upon NOX2 activation [20], and TXB 2 a marker of PA induced by arachidonic acid pathway [21]. Furthermore, these markers were reported to be correlated with atherosclerosis and cardiovascular disease in other settings [14,[22][23][24][25]. However, NOX2 activity modulation after PCSK9i treatment was never investigated and, while the inhibition of PA in patients treated with PCSK9i was previously demonstrated by Barale et al., whether this depends on free circulating PCSK9 reduction or on lowering oxLDL is still to be defined [14][15][16]26]. ...
Background: Proprotein convertase subtilisin kexin type 9 inhibitors (PCSK9i) lower LDL-cholesterol and slow atherosclerosis preventing cardiovascular events. While it is known that circulating PCSK9 enhances platelet activation (PA) and that PCSK9i reduce it, the underlying mechanism is not still clarified. Methods: In a multicenter before–after study in 80 heterozygous familial hypercholesterolemia (HeFH) patients on treatment with maximum tolerated statin dose ± ezetimibe, PA, soluble-NOX2-derived peptide (sNOX2-dp), and oxidized-LDL (ox-LDL) were measured before and after six months of PCSK9i treatment. In vitro study investigates the effects of plasma from HeFH patients before and after PCK9i on PA in washed platelets (wPLTs) from healthy subjects. Results: Compared to baseline, PCSK9i reduced the serum levels of LDL-c, ox-LDL, Thromboxane (Tx) B2, sNOX2-dp, and PCSK9 (p < 0.001). The decrease of TxB2 correlates with that of ox-LDL, while ox-LDL reduction correlated with PCSK9 and sNOX2-dp delta. In vitro study demonstrated that wPLTs resuspended in plasma from HeFH after PCSK9i treatment induced lower PA and sNOX2-dp release than those obtained using plasma before PCSK9i treatment. This reduction was vanished by adding ox-LDL. ox-LDL-induced PA was blunted by CD36, LOX1, and NOX2 inhibition. Conclusions: PCSK9i treatment reduces PA modulating NOX2 activity and in turn ox-LDL formation in HeFH patients.
Purpose
The proteome during lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice is unclear.
Materials and Methods
In this study, eight-week-old male C57BL/6 mice were intraperitoneally injected with LPS and sacrificed 18 hours after LPS administration to identify protein expression levels in lung tissue using tandem mass tag (TMT) analysis for relative quantification. Hematoxylin-eosin (HE) staining was used to evaluate lung injury in mice. Immunohistochemical staining was used to calculate the production of myeloperoxidase (MPO) and TUNEL staining was performed to detect apoptosis. GO functional clustering and KEGG pathway enrichment analyses were performed to determine functions of differentially expressed proteins (DEPs) and transduction pathways. Domain annotation and subcellular localization analysis of the DEPs were also performed. Furthermore, parallel reaction monitoring (PRM) analysis was used to verify the top 30 DEPs.
Results
A total of 5188 proteins were found to be expressed in lung tissues from LPS- and saline-treated mice. Among these proteins, 293 were differentially expressed between the two groups; 255 proteins were upregulated in the LPS-treated ALI mice, while 38 were downregulated. GO analysis showed that the DEPs are mainly extracellular, and KEGG analysis suggested that the DEPs are mainly enriched in the NOD-like receptor signaling pathway, complement and coagulation cascades and natural killer cell-mediated cytotoxicity. Enrichment of the DEPs is mainly peptidase S1A, serine proteases, peptidase S1, and the serpin domain. 26.6% of the DEPs are in the nucleus, 24.6% are in the cytosol, 19.1% are in the extracellular space, and 18.8% are in the plasma membrane. PRM validation showed that the trend of 30 DEPs was same with TMT analysis. Among these, Cytochrome b-245 heavy chain (Cybb), Monocyte differentiation antigen CD14 (Cd14) and Neutrophil gelatinase-associated lipocalin (NGAL) were the most obvious change.
Conclusions
Our results may help to identify markers and therapeutic targets for LPS-induced ALI.
