Immune effects of PI3K/Akt/HIF-1α-regulated glycolysis in polymorphonuclear neutrophils during sepsis.

BACKGROUND: Effective removal of pathogenic bacteria is key to improving the prognosis of sepsis. Polymorphonuclear neutrophils (PMNs) are the most important components of innate cellular immunity and play vital roles in clearing pathogenic bacteria. However, the metabolic characteristics and immunomodulatory pathways of PMNs during sepsis have not been investigated. In the present study, we explored the immune metabolism characteristics of PMNs and the mechanism by which neutrophilic glycolysis is regulated during sepsis. METHODS: Metabolomics analysis was performed on PMNs isolated from 14 septic patients, 26 patients with acute appendicitis, and 19 healthy volunteers. Transcriptome analysis was performed on the PMNs isolated from the healthy volunteers and the patients with sepsis to assess glycolysis and investigate its mechanism. Lipopolysaccharide (LPS) was used to stimulate the neutrophils isolated from the healthy volunteers at different time intervals to build an LPS-tolerant model. Chemotaxis, phagocytosis, lactate production, oxygen consumption rate (OCR), and extracellular acidification rate (ECAR) were evaluated. RESULTS: Transcriptomics showed significant changes in glycolysis and the mTOR/HIF-1α signaling pathway during sepsis. Metabolomics revealed that the Warburg effect was significantly altered in the patients with sepsis. We discovered that glycolysis regulated PMNs' chemotaxis and phagocytosis functions during sepsis. Lactate dehydrogenase A (LDHA) downregulation was a key factor in the inhibition of glycolysis in PMNs. This study confirmed that the PI3K/Akt-HIF-1α pathway was involved in the LDHA expression level and also influenced PMNs' chemotaxis and phagocytosis functions. CONCLUSIONS: The inhibition of glycolysis contributed to neutrophil immunosuppression during sepsis and might be controlled by PI3K/Akt-HIF-1α pathway-mediated LDHA downregulation. Our study provides a scientific theoretical basis for the management and treatment of patients with sepsis and promotes to identify therapeutic target for the improvement of immune function in sepsis.

Serum-soluble PD-L1 may be a potential diagnostic biomarker in sepsis.

To investigate whether serum-soluble PD-L1 (sPD-L1) is a potential biomarker for identifying sepsis. This study enrolled 64 septic patients, 29 patients with acute appendicitis, 33 patients with acute pancreatitis and 30 healthy volunteers. Sepsis was defined according to the Sepsis 3.0 criteria.[1] The associated clinical parameters were recorded, blood samples were collected on the first day of diagnosis, and serum sPD-L1 levels were measured using enzyme-linked immunosorbent assays. Compared with the control group, a significant increase in sPD-L1 levels was observed in patients with sepsis (n = 64). Increased sPD-L1 expression correlated strongly with increased clinical inflammatory values (CRP, PCT and WBC) and decreased immunological functional parameters (CD3+ , CD4+ and CD8+ cell counts). The area under the ROC curve (AUC) for sPD-L1 in combination with the sequential organ failure assessment (SOFA) score was superior to the AUC for either sPD-L1 or SOFA score in regard to the diagnosis of sepsis. sPD-L1 may represent a valuable biomarker for the diagnosis of sepsis.

Comprehensive Analysis of Common Different Gene Expression Signatures in the Neutrophils of Sepsis.

The central component of sepsis pathogenesis is inflammatory disorder, which is related to dysfunction of the immune system. However, the specific molecular mechanism of sepsis has not yet been fully elucidated. The aim of our study was to identify genes that are significantly changed during sepsis development, for the identification of potential pathogenic factors. Differentially expressed genes (DEGs) were identified in 88 control and 214 septic patient samples. Gene ontology (GO) and pathway enrichment analyses were performed using David. A protein-protein interaction (PPI) network was established using STRING and Cytoscape. Further validation was performed using real-time polymerase chain reaction (RT-PCR). We identified 37 common DEGs. GO and pathway enrichment indicated that enzymes and transcription factors accounted for a large proportion of DEGs; immune system and inflammation signaling demonstrated the most significant changes. Furthermore, eight hub genes were identified via PPI analysis. Interestingly, four of the top five upregulated and all downregulated DEGs were involved in immune and inflammation signaling. In addition, the most intensive hub gene AKT1 and the top DEGs in human clinical samples were validated using RT-PCR. This study explored the possible molecular mechanisms underpinning the inflammatory, immune, and PI3K/AKT pathways related to sepsis development.

Multiple versus single doses of dexamethasone in total hip arthroplasty: A protocol of randomized controlled trial.

BACKGROUND: Reduction of post-operative pain, nausea, and vomiting in patients undergoing total hip arthroplasty (THA) may facilitate earlier discharge from hospital and reduce healthcare costs. The recommended dose regimen of dexamethasone in THA has not been determined. The purpose of this study was performed to compare the efficiency of multiple versus single doses of dexamethasone for early postoperative pain treatment after THA. METHODS: This study was a randomized controlled trial which conducted in our hospital. Informed consent for participation in this trial was obtained from each patient before surgery. Two hundred patients undergoing THA received 1 dose of intravenous dexamethasone and 1 dose of normal saline (Group A), or 2 doses of intravenous dexamethasone (Group B). The primary outcome was visual analog scale pain scores in the immediate postoperative period. Secondary outcomes included postoperative opioid use, length of hospital stay, activity level during physical therapy, and hip range of motion. RESULTS: This clinical trial might provide some insights to estimate the safety of dexamethasone. TRIAL REGISTRATION: This study protocol was registered in Research Registry (researchregistry5460).