Early Phase Of Sepsis Research Articles

Multi-Organ Transcriptome Dynamics in a Mouse Model of Cecal Ligation and Puncture-Induced Polymicrobial Sepsis.

PurposeDuring sepsis, an excessive inflammatory immune reaction contributes to multi-organ dysfunction syndrome (MODS), a critical condition associated with high morbidity and mortality; however, the molecular mechanisms driving MODS remain elusive.MethodsWe used RNA sequencing to characterize transcriptional changes in the early phase of sepsis, at 6, 12, 24 hour time points in lung, kidney, liver, and heart tissues, in a cecal ligation and puncture (CLP)-induced polymicrobial sepsis murine model.ResultsThe CLP surgery induced significant changes (adj. p-value<0.05) in expression of hundreds of transcripts in the four organs tested, with the highest number exceeding 2,000 differentially expressed genes (DEGs) in all organs at 12 hours post-CLP. Over-representation analysis by functional annotations of DEGs to the Reactome database revealed the immune system, hemostasis, lipid metabolism, signal transduction, and extracellular matrix remodeling biological processes as significantly altered in at least two organs, while metabolism of proteins and RNA were revelaed as being liver tissue specific in the early phase of sepsis.ConclusionRNA sequencing across organs and time-points in the CLP murine model allowed us to study the trajectories of transcriptome changes demonstrating alterations common across multiple organs as well as biological pathways altered in an organ-specific manner. These findings could pave new directions in the research of sepsis-induced MODS and indicate new sepsis treatment strategies.

Polymorphonuclear Myeloid-Derived Cells That Contribute to the Immune Paralysis Are Generated in the Early Phase of Sepsis via PD-1/PD-L1 Pathway.

Immune paralysis is a protracted state of immune suppression following the early/acute inflammatory phase of sepsis. CD11b+ Gr-1+ cells induced during sepsis are heterogeneous myeloid-derived cells (MDCs). This study investigated the contribution of MDCs to immune paralysis. Treatment of mice with zymosan (ZM) induced a marked increase in the total number of splenocytes with an increase in the proportion of Gr-1hi cells and a decrease in the proportion of T cells on day 7; levels of these cells eventually return to levels similar to those of control mice on day 21. T-cell activation and gamma interferon (IFN-γ) expression by CD8+ T cells were clearly impaired in ZM-treated mice on day 21 (d21-ZM mice). Gr-1hi cells showed a CD11b+ Ly6Ghi polymorphonuclear phenotype. Injection of lipopolysaccharide (LPS) into d21-ZM mice impaired interleukin 6 (IL-6) production in serum, accompanied by accumulation of CD11b+ Gr-1hi cells in the peripheral blood. Transfer of Gr-1hi cells from d21-ZM mice into intact mice impaired IL-6 production, but similar transfer of Gr-1hi cells from PD-1/PD-L1-deficient d21-ZM mice showed no such suppressive effect. Conversely, either depletion of Gr-1hi cells by treatment with anti-Gr-1 monoclonal antibody (MAb) or neutralization of the PD-1/PD-L1 pathway by anti-PD-1 and anti-PD-L1 MAbs during the induction phase of sepsis ameliorated ZM-induced immune suppression. Our results suggest that the PD-1/PD-L1-mediated generation of Gr-1hi cells in the early phase of sepsis is required for the late phase of immune paralysis.

Microglial Activation Modulates Neuroendocrine Secretion During Experimental Sepsis.

Sepsis promotes an inflammatory state in the central nervous system (CNS) that may cause autonomic, cognitive, and endocrine changes. Microglia, a resident immune cell of the CNS, is activated in several brain regions during sepsis, suggesting its participation in the central alterations observed in this disease. In this study, we aimed to investigate the role of microglial activation in the neuroendocrine system functions during systemic inflammation. Wistar rats received an intracerebroventricular injection of the microglial activation inhibitor minocycline (100μg/animal), shortly before sepsis induction by cecal ligation and puncture. At 6 and 24h after surgery, hormonal parameters, central and peripheral inflammation, and markers of apoptosis and synaptic function in the hypothalamus were analyzed. The administration of minocycline decreased the production of inflammatory mediators and the expression of cell death markers, especially in the late phase of sepsis (24h). With respect to the endocrine parameters, microglial inhibition caused a decrease in oxytocin and an increase in corticosterone and vasopressin plasma levels in the early phase of sepsis (6h), while in the late phase, we observed decreased oxytocin and increased ACTH and corticosterone levels compared to septic animals that did not receive minocycline. Prolactin levels were not affected by minocycline administration. The results indicate that microglial activation differentially modulates the secretion of several hormones and that this process is associated with inflammatory mediators produced both centrally and peripherally.

Immunomodulation in Sepsis - A Case Report

Sepsis and septic shock affect anywhere between 100 and 1000/100,000 person-years and 19 per 100,000 person-years depending on the cohort studied, with mortality rates ranging between 20% and 50%. The recently updated Sepsis 3.0 consensus definitions state that sepsis is an infection accompanied by life-threatening organ dysfunction caused by a dysregulated host response. Given the pivotal role of cytokine production in sepsis and post major surgery, it follows that removal of these substances may attenuate the response particularly in the early phase of sepsis.

Newly Developed Recombinant Antithrombin Protects the Endothelial Glycocalyx in an Endotoxin-Induced Rat Model of Sepsis.

(1) Background: The endothelial glycocalyx is a primary target during the early phase of sepsis. We previously reported a newly developed recombinant non-fucosylated antithrombin has protective effects in vitro. We further evaluated the effects of this recombinant antithrombin on the glycocalyx damage in an animal model of sepsis. (2) Methods: Following endotoxin injection, in Wistar rats, circulating levels of hyaluronan, syndecan-1 and other biomarkers were evaluated in low-dose or high-dose recombinant antithrombin-treated animals and a control group (n = 7 per group). Leukocyte adhesion and blood flow were evaluated with intravital microscopy. The glycocalyx was also examined using side-stream dark-field imaging. (3) Results: The activation of coagulation was inhibited by recombinant antithrombin, leukocyte adhesion was significantly decreased, and flow was better maintained in the high-dose group (both p < 0.05). Circulating levels of syndecan-1 (p < 0.01, high-dose group) and hyaluronan (p < 0.05, low-dose group; p < 0.01, high-dose group) were significantly reduced by recombinant antithrombin treatment. Increases in lactate and decreases in albumin levels were significantly attenuated in the high-dose group (p < 0.05, respectively). The glycocalyx thickness was reduced over time in control animals, but the derangement was attenuated and microvascular perfusion was better maintained in the high-dose group recombinant antithrombin group (p < 0.05). (4) Conclusions: Recombinant antithrombin maintained vascular integrity and the microcirculation by preserving the glycocalyx in this sepsis model, effects that were more prominent with high-dose therapy.

Examination of intestinal ultrastructure, bowel wall apoptosis and tight junctions in the early phase of sepsis

Gut hyperpermeability can be caused by either apoptosis of the intestinal epithelium or altered status, permeability or porosity of tight junctions. This project aims to elucidate these mechanisms in the early phase of sepsis. Eighteen male wild type mice were randomized to two groups. All mice received one single gavage of fluorescein isothiocyanate (FITC) dextran 30 min before intervention. One group (n = 10) underwent cecal ligation and puncture to induce sepsis. The other group (n = 8) was sham operated. Septic animals exhibited significantly increased permeability for FITC 8 h post-operatively. Significantly increased serum interleukin-6, tumor-necrosis-factor-alpha and interleukin-1-beta confirmed sepsis. Septic animals showed significant bowel wall inflammation of ileum and colon samples. PCR revealed significantly increased expression of claudin-2 and decreased expressions of claudin-4, tight-junction-protein-1 and occludin-1 resembling increased permeability of tight junctions. However, these alterations could not be confirmed at the protein level. Light microscopy revealed significant dilatation of intercellular spaces at the basal sections of intestinal epithelial cells (IEC) in septic animals confirmed by increased intercellular spaces at the level of tight junctions and adherens junctions in electron microscopy (TEM). In small angle X-ray scattering no increase in number or size of nanopores could be shown in the bowel wall. HOECHST staining and PCR of ileum samples for apoptosis markers proofed no relevant differences in intestinal epithelial cell apoptosis between the groups. Intestinal hyperpermeability in septic animals was most likely caused by alterations of the intercellular contacts and not by apoptosis or increased size/number of nanopores of intestinal epithelial cells in this murine model of early sepsis.

Combinatorial Single-Cell Analyses of Granulocyte-Monocyte Progenitor Heterogeneity Reveals an Early Uni-potent Neutrophil Progenitor

Granulocyte-monocyte progenitors (GMPs) have been previously defined for their potential to generate various myeloid progenies such as neutrophils and monocytes. Although studies have proposed lineage heterogeneity within GMPs, it is unclear if committed progenitors already exist among these progenitors and how they may behave differently during inflammation. By combining single-cell transcriptomic and proteomic analyses, we identified the early committed progenitor within the GMPs responsible for the strict production of neutrophils, which we designate as proNeu1. Our dissection of the GMP hierarchy led us to further identify a previously unknown intermediate proNeu2 population. Similar populations could be detected in human samples. proNeu1s, but not proNeu2s, selectively expanded during the early phase of sepsis at the expense of monocytes. Collectively, our findings help shape the neutrophil maturation trajectory roadmap and challenge the current definition of GMPs.

Outlining key inflammation associated parameters during early phase of an experimental gram-negative sepsis model in rhesus macaques (Macaca mulatta)

Abstract Sepsis is a life-threatening syndrome characterized by metabolic and systemic dysregulation in the presence of an invading pathogen, such as bacteria or fungi. In the initial stages of this syndrome, the body, in an attempt to eradicate the pathogen, secretes high levels of pro-inflammatory cytokines and chemokines that leads to an anti-inflammatory state, which leads to organ dysfunction and death. Despite the efforts to find targeted therapeutics to treat septic patients, physicians rely on the administration of antibiotics and fluids. Hence, the development of novel targeted therapeutics to treat septic patients at early stages of sepsis is highly important to save the lives of these patients. The aim of this study was to identify inflammation markers during the early phase of sepsis in rhesus macaque. Four rhesus macaque were given an intravenous dose of 1010 CFU/kg of E. coli. Blood samples were collected before, 30 minutes, 2, 4, 6 and 8 hours after E. coli infusion. Physiological parameters, bacteremia, endotoxemia, C-reactive protein (CRP), procalcitonin (PCT), and cytokines and chemokines were determined for each animal at each time point. Bacteremia was present in all animals from 30 minutes to 3 hours after E. coli infusion. Endotoxin, CRP and PCT levels remained detectable during the whole experimental window. Signature cytokines and chemokines such as TNFα, MIP1α, and MIP1β peaked about 2 hours after E. coli infusion and decreased thereafter. Plasma IL6, IL12p40, IFNγ, and IL1Ra, ITAC, MIG, IP10 and MCP1, remained at detectable levels after 4 hours of E. coli infusion. This non-human primate model could be useful for the assessment of new therapeutics aiming to suppress key inflammatory markers throughout sepsis early phases.

Decreased endothelial glycocalyx thickness is an early predictor of mortality in sepsis.

Microcirculatory alterations play an important role in the early phase of sepsis. Shedding of the endothelial glycocalyx is regarded as a central pathophysiological mechanism causing microvascular dysfunction, contributing to multiple organ failure and death in sepsis. The objective of this study was to investigate whether endothelial glycocalyx thickness at an early stage in septic patients relates to clinical outcome. We measured the perfused boundary region (PBR), which is inversely proportional to glycocalyx thickness, of sublingual microvessels (5–25 µm) using sidestream dark field imaging. The PBR in 21 patients with sepsis was measured within 24 h of admission to the intensive care unit (ICU). In addition, we determined plasma markers of microcirculatory dysfunction and studied their correlation with PBR and mortality. Endothelial glycocalyx thickness in sepsis was significantly lower for non-survivors as compared with survivors, indicated by a higher PBR of 1.97 [1.85, 2.19]µm compared with 1.76 [1.59, 1.97] µm, P=0.03. Admission PBR was associated with hospital mortality with an area under the curve of 0.778 based on the receiver operating characteristic curve. Furthermore, PBR correlated positively with angiopoietin-2 (rho=0.532, P=0.03), indicative of impaired barrier function. PBR did not correlate with Acute Physiology and Chronic Health Evaluation IV (APACHE IV), Sequential Organ Failure Assessment score (SOFA score), lactate, syndecan-1, angiopoietin-1 or heparin-binding protein. An increased PBR within the first 24 h after ICU admission is associated with mortality in sepsis. Further research should be aimed at the pathophysiological importance of glycocalyx shedding in the development of multi-organ failure and at therapies attempting to preserve glycocalyx integrity.

Long-Term Microgliosis Driven by Acute Systemic Inflammation.

Severe sepsis, a systemic inflammatory response to infection, is an increasing cause of morbidity in intensive care units. During sepsis, the vasculature is profoundly altered, leading to release of microbial virulence factors and proinflammatory mediators to surrounding tissue, causing severe systemic inflammatory responses and hypoxic injury of multiple organs. To date, multiple studies have explored pathologic conditions in many vital organs, including lungs, liver, and kidneys. Although data suggest that sepsis is emerging as a key driver of chronic brain dysfunction, the immunological consequence of severe inflammatory responses in the brain remain poorly understood. In this study, we used C57BL/6 sepsis mouse models to establish a disease phenotype in which septic mice with various degrees of severity recover. In the early phases of sepsis, monocytes infiltrate the brain with significantly elevated proinflammatory cytokine levels. In recovered animals, monocytes return to vehicle levels, but the number of brain-resident microglia is significantly increased in the cortex, the majority of which remain activated. The increase in microglia number is mainly due to self-proliferation, which is completely abolished in CCR2 knockout mice. Collectively our data suggest that early monocyte infiltration causes permanent changes to microglia during sepsis, which may ultimately dictate the outcome of future infections and neuropathological diseases.

Effect of Preconditioned Mesenchymal Stromal Cells on Early Microvascular Disturbance in a Mouse Sepsis Model.

Septic patients often die in a context of multiple organ dysfunction syndrome (MODS), despite the macro-hemodynamic parameters being normalized and after the onset of antibiotic therapy. Microcirculation injury during sepsis affects capillary permeability and leukocyte-endothelium interactions and is thought to be instrumental in organ injury. Several studies have demonstrated a beneficial effect of mesenchymal stromal cells (MSCs) injection on survival and organ dysfunctions in sepsis models. In vivo activity of MSCs also appears to be very much dependent on the information provided before injection. Indeed preconditioning by interferon γ (IFNγ; MSC-IFNγ) increases immunosuppressive capacity of MSCs in vitro and in vivo. Therefore, the objective was to evaluate the effect of MSC naive or IFNγ preconditioned on leukocyte-endothelium interactions in a polymicrobial sepsis model by intraperitoneal feces injection. Six hours (H6) after this induction, we used intravital microscopy in mice cremaster muscle venules to study the flow behavior of leukocytes. Plasmas were harvested to evaluate inflammation level and endothelial activation. We showed that MSC-IFNγ have a beneficial effect on microcirculation, by increasing the flow of white blood cells (WBCs) and the percentage of venules containing flowing WBCs, by significantly reducing the adhesion of WBCs and by increasing the average red blood cell velocity (VRBC). In conclusion, our results suggest that intravenous injection of preconditioned MSC-IFNγ improves microvascular hemodynamics in early phases of sepsis.

The Combined Effect of α7n-Acetylcholine and β2-Adrenergic Receptors Agonists on the Implementation of the Cholinergic Anti-Inflammatory Pathway in Early Phase of Sepsis

The Combined Effect of α7n-Acetylcholine and β2-Adrenergic Receptors Agonists on the Implementation of the Cholinergic Anti-Inflammatory Pathway in Early Phase of Sepsis

Outlining key inflammation-associated parameters during early phase of an experimental gram-negative sepsis model in rhesus macaques (Macaca mulatta).

The aim of this study was to identify inflammation‐associated markers during the early phase of sepsis in rhesus macaque. Four rhesus macaques were given an intravenous dose of 1010 CFU/kg of E. coli. Blood samples were collected before, or 30 minutes, 2, 4, 6 and 8 hours after E. coli infusion. Physiological parameters, bacteremia, endotoxemia, C‐reactive protein (CRP), procalcitonin (PCT), and plasma cytokines/chemokines were determined for each animal. Bacteremia was present in all animals from 30 minutes to 3 hours after E. coli infusion whereas endotoxin was detected during the full‐time course. CRP and PCT levels remained at detectable levels during the whole experimental window suggesting an ongoing inflammatory process. Signature cytokines and chemokines such as TNF‐α, MIP‐1α, and MIP‐1β peaked about 2 hours after E. coli infusion and decreased thereafter. Plasma IL‐6, IL‐12p40, IFN‐γ, and IL‐1Ra, as well as I‐TAC, MIG, IP‐10 and MCP‐1, remained at detectable levels after 4 hours of E. coli infusion. This nonhuman primate model could be useful for the assessment of new therapeutics aiming to suppress key inflammatory markers throughout sepsis early phases.

Correlation between Serum Magnesium and Lactate Levels at the Time of ICU Admission and Early Phase of Sepsis

Background: As the fourth abundant electrolyte in the body, magnesium has critical roles in aerobic metabolism and regulation of the immune system. Few studies investigate the association between magnesium status of critically ill septic patients and lactate acidosis in the intensive care unit (ICU). In this study, serum magnesium level and lactate level were evaluated at both admission time and time of sepsis. Methods: This was a prospective, cross-sectional study conducted at general ICU of a tertiary referral teaching hospital. Hypomagnesemia was defined as a serum magnesium concentration of less than 1.7 mg/dL. Mann-Whitney test and independent-sample t-test were used to analyze nonparametric and parametric data, respectively. Results: Of 50 sepsis patients, 32 patients were normomagnesemic, and 18 were hypomagnesemic. Hypomagnesemic patients have significantly higher lactate serum level at the time of sepsis compared to normomagnesemic patients [2.32 (1.96-3.29) vs. 1.94 (1.80-2.15) mg/dl respectively, p&lt;0.001]. There were significant differences between normomagnesemic and hypomagnesemic septic patients in Acute Physiology and Chronic Health Evaluation (APACHE) II score at sepsis time (9.44 ± 4.33 vs. 11.67 ± 3.83, p=0.46), and Sequential Organ Failure Assessment (SOFA) score [3 (3.00-5.00) vs. 4 (3.75-6.25), p=0.04]. Also, 28-day mortality because of sepsis (50% respectively, p&lt;0.001), duration of mechanical ventilation [12.00 (4.00-14.25) days respectively, p&lt;0.01] and ICU stay [14.00 (12.75-17.25) days respectively, p&lt;0.01] were significantly higher in hypomagnesemic groups. Conclusion: Admission hypomagnesemia in sepsis patients may increase serum lactate concentration, duration of ventilation, duration of ICU stay and mortality.

Population pharmacokinetics and pharmacodynamics of piperacillin in critically ill patients during the early phase of sepsis.

This study aimed to characterize the population pharmacokinetics (PKs) of piperacillin and investigate probability of target attainment (PTA) and cumulative fraction of response (CFR) of various dosage regimens in critically ill patients during the early phase of sepsis. Forty-eight patients treated with piperacillin/tazobactam were recruited. Five blood samples were drawn before and during 0-0.5, 0.5-2, 2-4 and 4-6 or 8h after administration. Population PKs was analyzed using NONMEM®. The PTA of 90%fT>MIC target and CFR were determined by Monte Carlo simulation. The two compartment model best described the data. Piperacillin clearance (CL) was 5.37 L/h, central volume of distribution (V1) was 9.35 L, and peripheral volume of distribution was 7.77 L. Creatinine clearance (CLCr) and mean arterial pressure had a significant effect on CL while adjusted body weight had a significant impact on V1. Subtherapeutic concentrations can occur during the early phase of sepsis in critically ill patients with normal renal function. The usual dosage regimen, 4g of piperacillin infused over 0.5h every 6h, could not achieve the target for susceptible organisms with MIC 16mg/L in patients with CLCr ≥ 60mL/min. Our proposed regimen for the patients with CLCr 60-120mL/min was an extended 2h infusion of 4g of piperacillin every 6h. Most regimens provided CFR ≥ 90% for the E. coli infection while there was no dosage regimen achieved a CFR of 90% for the P. aeruginosa infection.

Lung nitroxidative stress in mechanically-ventilated septic patients: A pilot study

PurposeDuring sepsis and mechanical ventilation oxidative stress is generated by endothelial and inflammatory lung cells. Our main objective was to study pulmonary NO (nitric oxide) production and nitroxidative stress in mechanically-ventilated septic patients. MethodsWe study 69 mechanically ventilated patients, 36 with sepsis and 33 without sepsis within the first 48 h of ICU admission compared with 33 mechanically ventilated patients without sepsis (MV) plus eight operating room patients without lung disease served as control healthy group (ORCG). Nitrite plus nitrate (NOx−), 3-nitrotyrosine and malondialdehyde (MDA) in bronchoalveolar lavage fluid (BALF) were analyzed. ResultsBALF NOx−, BALF 3-nitrotyrosine, BALF MDA, and plasma NOx− were higher in the Sepsis than in MV patients (all p < .05). Both SG and MV patients had higher BALF NOx− than the healthy control group (p < .001). In the Sepsis patients, the ICU non-survivors had higher levels of BALF NOx− than ICU survivors 80(70–127) μM versus 31(15–47) μM, p < .001. ConclusionsWe conclude that during early phases of sepsis there is an enhanced lung nitroxidative stress due to an increase of NO production leading to secondary NO-derived oxidants, which promote protein nitration and lipid peroxidation.

Rapid susceptibility testing of multi-drug resistant Escherichia coli and Klebsiella by glucose metabolization monitoring.

Background The increasing number of multi-drug resistant (MDR) bacteria provides enormous challenges for choosing an appropriate antibiotic therapy in the early phase of sepsis. While bacterial identification has been greatly accelerated by the introduction of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), the antibiotic susceptibility testing (AST) remains time-consuming. Here, we present a rapid susceptibility testing method for testing Gram-negative bacteria, exemplarily validated for Escherichia coli and Klebsiella spp. Methods Gram-negative isolates (E. coli and Klebsiella spp.) were either taken as single colonies from agar plates (n=136) or directly extracted and identified from positive blood cultures (n=42) using MALDI-TOF MS. Bacteria were incubated in glucose-supplemented Luria broths (LBs) each containing one antibiotic (ceftazidime, piperacillin, imipenem and ciprofloxacin), routinely used to classify Gram-negative bacteria in Germany. To determine susceptibility the dynamics of glucose utilization in bacterial suspensions were quantitatively measured in the presence or absence of antibiotics designated liquid-AST (L-AST). Results The L-AST can be run on clinical-chemistry analyzers and integrated into laboratory routines. It yields critical resistance information within 90-150 min downstream of a MS-based identification. The results showed a high concordance with routine susceptibility testing, with less than 1% very major errors (VME) and 3.51% major errors (ME) for 178 assessed isolates. Analysis of turnaround time (TAT) for 42 clinical samples indicated that L-AST results could be obtained 34 h earlier than the routine results. Conclusions As exemplified for E. coli and Klebsiella spp., L-AST provides substantial acceleration of susceptibility testing following MALDI-TOF MS identification. The assay is a simple and low-cost method that can be integrated into clinical laboratory to allow for 24/7 AST. This approach could improve antibiotic therapy.

In Vivo Effects of Neostigmine and Physostigmine on Neutrophil Functions and Evaluation of Acetylcholinesterase and Butyrylcholinesterase as Inflammatory Markers during Experimental Sepsis in Rats.

Introduction Recent studies have shown that acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) may serve as important diagnostic and therapeutic targets in sepsis. Since polymorphonuclear neutrophils (PMNs) play a pivotal role in the early phase of sepsis, we evaluated the potential therapeutic effects of cholinesterase inhibitors on PMN functions during cecal ligation and puncture- (CLP-) induced sepsis and investigated the roles of AChE and BChE as inflammatory markers under standardized experimental conditions. Methods Sham surgery or CLP was performed in male Wistar rats (n = 60). Animals were randomized into four groups: physostigmine, 100 μg/kg; neostigmine, 75 μg/kg; 0.9% saline (control group); and sham group, each applied four times over 24 h. The levels of reactive oxygen species (ROS) production and CD11b/CD62l expression were quantified by flow cytometry at t = 0, 6, 15, 20, and 24 h. Blood gas analysis as well as AChE and BChE activity levels was measured by validated point-of-care measurements. Clinical scores and survival times were determined. Results CLP induced a significant increase in ROS production and CD11b upregulation by rat PMNs. Treatment with physostigmine or neostigmine significantly reduced ROS production and CD11b upregulation by PMNs 20 h after CLP induction. In physostigmine-treated animals, survival times were significantly improved compared to the control animals, but not in neostigmine-treated animals. While AChE activity significantly decreased in the control animals at t > 6 h, AChE activity did not change in the sham group. BChE activity decreased at t > 20 h in the control animals. Conclusion While AChE activity may serve as an acute inflammatory marker, BChE activity shows a delayed decrease. Administration of centrally acting physostigmine in CLP-induced sepsis in rats has protective effects on PMN functions and improves survival times, which may be of interest in clinical practice.

Diagnostic value of NT-proCNP compared to NSE and S100B in cerebrospinal fluid and plasma of patients with sepsis-associated encephalopathy

Sepsis-associated encephalopathy (SAE) has significant impact on the neurocognitive outcome of sepsis survivors. This study was conducted to analyze the amino-terminal propeptide of the C-type natriuretic peptide (NT-proCNP) as a biomarker for SAE in comparison to neuron-specific enolase (NSE) and S100B protein. Cerebrospinal fluid (CSF) and plasma samples from twelve septic patients with SAE and nine non-septic controls without encephalopathy were analyzed. The assessment of SAE comprised a neuropsychiatric examination, delirium screening using the confusion assessment method in the ICU (CAM-ICU) and magnetic resonance imaging (MRI) in all participants. NSE, S100B and NT-proCNP were measured in plasma at study days 1, 3 and 7 in sepsis patients, once in controls and once in the CSF of both groups. The long-term outcome was assessed using the validated Barthel index (BI). Plasma NT-proCNP levels were significantly higher in the sepsis cohort compared to controls with peak concentrations at study day 1 (10.1 ± 6.6 pmol/l vs. 3.3 ± 0.9 pmol/l; p < 0.01) and a decrease over time. Plasma NT-proCNP levels at day 7 correlated with NT-proCNP in CSF (r = 0.700, p < 0.05). A comparable decrease of significantly higher plasma S100B values in sepsis patients compared to controls was observed. Plasma NSE levels were not significantly different between both groups. CSF NT-proCNP levels just tended to be higher in sepsis patients compared to controls and tended to be higher in patients with septic brain lesions seen on MRI. In the sepsis cohort CSF NT-proCNP levels correlated with CSF Interleukin-6 (IL-6) levels (r = 0.616, p < 0.05) and systemic inflammation represented by high plasma procalcitonin (PCT) levels at day 3 (r = 0.727, p < 0.05).The high peak concentration of plasma NT-proCNP in the early phase of sepsis might help to predict the emergence of SAE during the further course of disease. NT-proCNP in plasma might, in contrast to CSF, indicate neurological impairment in patients with SAE.

Protection of the endothelial glycocalyx by antithrombin in an endotoxin-induced rat model of sepsis

IntroductionInjury and loss of the endothelial glycocalyx occur during the early phase of sepsis. We previously showed that antithrombin has a protective effect on this structure in vitro. Here, we investigated the possible protective effects of antithrombin in an animal model of sepsis. MethodsWistar rats were injected with endotoxin, and circulating levels of syndecan-1, hyaluronan, albumin, lactate and other biomarkers were measured in an antithrombin-treated group and an untreated control group (n = 6 in each group). Intravital microscopy was used to observe leukocyte adhesion, microcirculation, and syndecan-1 staining. ResultsThe circulating levels of syndecan-1 and hyaluronan were significantly reduced in the antithrombin-treated group, compared with the untreated controls. Lactate levels and albumin reduction were significantly attenuated in the antithrombin-treated group. Intravital microscopic observation revealed that both leukocyte adhesion and blood flow were better maintained in the treatment group. The syndecan-1 lining was disrupted after endotoxin treatment, and this derangement was attenuated by treatment with antithrombin. ConclusionAntithrombin effectively maintained microcirculation and vascular integrity by protecting the glycocalyx in a rat sepsis model.