Sepsis In Animals Research Articles

Caffeine Consumption Helps Honey Bees Fight a Bacterial Pathogen.

Caffeine has long been used as a stimulant by humans. Although this secondary metabolite is produced by some plants as a mechanism of defense against herbivores, beneficial or detrimental effects of such consumption are usually associated with dose. The Western honey bee, Apis mellifera, can also be exposed to caffeine when foraging at Coffea and Citrus plants, and low doses as are found in the nectar of these plants seem to boost memory learning and ameliorate parasite infection in bees. In this study, we investigated the effects of caffeine consumption on the gut microbiota of honey bees and on susceptibility to bacterial infection. We performed in vivo experiments in which honey bees, deprived of or colonized with their native microbiota, were exposed to nectar-relevant concentrations of caffeine for a week, then challenged with the bacterial pathogen Serratia marcescens. We found that caffeine consumption did not impact the gut microbiota or survival rates of honey bees. Moreover, microbiota-colonized bees exposed to caffeine were more resistant to infection and exhibited increased survival rates compared to microbiota-colonized or microbiota-deprived bees only exposed to the pathogen. Our findings point to an additional benefit of caffeine consumption in honey bee health by protecting against bacterial infections. IMPORTANCE The consumption of caffeine is a remarkable feature of the human diet. Common drinks, such as coffee and tea, contain caffeine as a stimulant. Interestingly, honey bees also seem to like caffeine. They are usually attracted to the low concentrations of caffeine found in nectar and pollen of Coffea plants, and consumption improves learning and memory retention, as well as protects against viruses and fungal parasites. In this study, we expanded these findings by demonstrating that caffeine can improve survival rates of honey bees infected with Serratia marcescens, a bacterial pathogen known to cause sepsis in animals. However, this beneficial effect was only observed when bees were colonized with their native gut microbiota, and caffeine seemed not to directly affect the gut microbiota or survival rates of bees. Our findings suggest a potential synergism between caffeine and gut microbial communities in protection against bacterial pathogens.

Dietary supplementation of probiotics fermented Chinese herbal medicine Sanguisorba officinalis cultures enhanced immune response and disease resistance of crucian carp (Carassius auratus) against Aeromonas hydrophila

Aeromonas hydrophila, a Gram-negative bacterium, is one of the major pathogens causing bacterial sepsis in aquatic animals due to drug resistance and pathogenicity, which could cause high mortality and serious economic losses to the aquaculture. Sanguisorba officinalis (called DiYu in Chinese, DY) is well known as herbal medicine, which could inhibit the growth of pathogenic bacteria, hemostasis and regulate the immune response. Moreover, the active ingredients in DY could remarkably reduce drug resistance. In this study, we investigated the effects of probiotic fermentation cultures on A. hydrophila through in vitro and in vivo experiments. Three lactic acid bacteria, including Lactobacillus rhamnosus (LGG), Lactobacillus casei (LC) and Lactobacillus plantarum (LP), were selected to ferment the Chinese herbal medicine DY. The assays of antagonism showed that all three fermented cultures could influence the ability of A. hydrophila growth, among which L. rhamnosus fermented DY cultures appeared to be the strongest inhibitory effect. In addition, the biofilm determination revealed that L. rhamnosus fermented DY cultures could significantly inhibit the biofilm formation of A. hydrophila compared to the other groups. Furthermore, protease, lecithinase and urease activities were found in the three fermentation cultures. Three probiotics fermented DY cultures were orally administration with crucian carp to evaluate the growth performance, immunological parameters and pathogen resistance. The results showed that the three fermentation cultures could promote the growth performance of crucian carp, and the immunoglobulins, antioxidant-related enzymes and immune-related genes were significantly enhanced. Besides, the results showed that crucian carp received L. rhamnosus (60.87%), L. casei (56.09%) and L. plantarum (41.46%) fermented DY cultures had higher survival rates compared with the control group after infection with A. hydrophila. Meanwhile, the pathological tissue results revealed that the probiotic fermented cultures could largely improve the tissues damage caused by the pathogenic bacteria. In conclusion, this study proved that the fermentation cultures of three probiotics could effectively inhibit the growth of A. hydrophila, regulate the level of immune response and improve the survival rate against A. hydrophila in crucian carp. The present data suggest that probiotic fermented Sanguisorba officinalis act as a potential gut-targeted therapy regimens to protecting fish from pathogenic bacteria infection.

Neutrophils as regulators of macrophage-induced inflammation in a setting of allogeneic bone marrow transplantation.

SummaryClinical data reveal that patients with allogeneic hematopoietic stem cell transplantation (HSCT) are vulnerable to infection and prone to developing severe sepsis, which greatly compromises the success of transplantation, indicating a dysregulation of inflammatory immune response in this clinical setting. Here, by using a mouse model of haploidentical bone marrow transplantation (haplo-BMT), we found that uncontrolled macrophage inflammation underlies the pathogenesis of both LPS- and E.coli-induced sepsis in recipient animals with graft-versus-host disease (GVHD). Deficient neutrophil maturation in GVHD mice post-haplo-BMT diminished modulation of macrophage-induced inflammation, which was mechanistically dependent on MMP9-mediated activation of TGF-β1. Accordingly, adoptive transfer of mature neutrophils purified from wild-type donor mice inhibited both sterile and infectious sepsis in GVHD mice post-haplo-BMT. Together, our findings identify a novel mature neutrophil-dependent regulation of macrophage inflammatory response in a haplo-BMT setting and provide useful clues for developing clinical strategies for patients suffering from post-HSCT sepsis.

Endothelial Dysfunction and Impaired Neurovascular Coupling Responses Precede Cognitive Impairment in a Mouse Model of Geriatric Sepsis.

Sepsis is a life-threatening condition, the incidence of which is significantly increased in elderly patients. One of the long-lasting effects of sepsis is cognitive impairment defined as a new deficit or exacerbation of preexisting deficits in global cognition or executive function. Normal brain function is dependent on moment-to-moment adjustment of cerebral blood flow to match the increased demands of active brain regions. This homeostatic mechanism, termed neurovascular coupling (NVC, also known as functional hyperemia), is critically dependent on the production of vasodilator NO by microvascular endothelial cells in response to mediators released from activated astrocytes. The goal of this study was to test the hypothesis that sepsis in aging leads to impairment of NVC responses early after treatment and that this neurovascular dysfunction associates with impairments in cognitive performance and vascular endothelial dysfunction. To test this hypothesis, we used a commonly studied bacterial pathogen, Listeria monocytogenes, to induce sepsis in experimental animals (males, 24 months of age) and subjected experimental animals to a standard clinical protocol of 3 doses of ampicillin i.p. and 14 days of amoxicillin added to the drinking water. NVC responses, endothelial function and cognitive performance were measured in septic and age-matched control groups within 14 days after the final antibiotic treatment. Our data demonstrate that sepsis in aging significantly impairs NVC responses measured in somatosensory cortex during whisker stimulation, significantly impairs endothelial function in isolated and pressure cannulated aorta rings in response to acetylcholine stimulation. No significant impairment of cognitive function in post-sepsis aged animals has been observed when measured using the PhenoTyper homecage based system. Our findings suggest that sepsis-associated endothelial dysfunction and impairment of NVC responses may contribute to long-term cognitive deficits in older sepsis survivors.

Veterinary perspective of the renal system in sepsis

This paper aims to review, discuss and define the factors associated with development of kidney injury in patients with sepsis, diagnosis alternatives, therapy and prevention, offering to the veterinarians an updated guide to improve the prognosis of sepsis patients. Sepsis is a clinical condition that leads to systemic complications and to multiple organ dysfunction syndrome (MODS), mainly due to poor tissue perfusion in humans and animals. Acute kidney injury (AKI) is considered the most frequent and lethal among organ complications secondary to sepsis, however the etiology of AKI in patients with sepsis is complex and multifactorial and not completely elucidated. Early diagnosis of AKI is difficult and consequently the treatment is not very successful, due to hemodynamic aspects. The ultrasonography seems to be a promising exam for early diagnosis of this lesion, especially with the advent of contrast-enhanced ultrasonography (CEUS) technique, which makes possible to detect microcirculation changes in the renal parenchyma, opening the door for a variety of physiological, clinical and therapeutic applications, however, studies proving CEUS accuracy for early detection of renal damage related to sepsis in humans and animals are still necessary.

Potent intracellular antibacterial activity of a marine peptide-N6NH2 and its D-enantiomer against multidrug-resistant Aeromonas veronii.

Aeromonas veronii can cause a variety of diseases such as sepsis in humans and animals. However, there has been no effective way to eradicate A. veronii. In this study, the intracellular antibacterial activities of the C-terminal aminated marine peptide N6 (N6NH2) and its D-enantiomer (DN6NH2) against A. veronii were investigated in macrophages and in mice, respectively. The result showed that DN6NH2 with the minimum inhibitory concentration(MIC) of 1.62 μM is more resistant to cathepsin B than N6NH2 (3.23 μM). The penetration percentages of the cells treated with 4-200 μg/mL fluorescein isothiocyanate(FITC)-DN6NH2 were 52.5-99.6%, higher than those of FITC-N6NH2 (27.0-99.1%). Both N6NH2 and DN6NH2 entered macrophages by macropinocytosis and an energy-dependent manner. DN6NH2 reduced intracellular A. veronii by 34.57%, superior to N6NH2 (19.52%). After treatment with 100 μg/mL DN6NH2, the levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-1β were reduced by 53.45%, 58.54%, and 44.62%, respectively, lower than those of N6NH2 (15.65%, 12.88%, and 14.10%, respectively); DN6NH2 increased the IL-10 level (42.94%), higher than N6NH2 (7.67%). In the mice peritonitis model, 5 μmol/kg DN6NH2 reduced intracellular A. veronii colonization by 73.22%, which was superior to N6NH2 (32.45%) or ciprofloxacin (45.67%). This suggests that DN6NH2 may be used as the candidate for treating intracellular multidrug-resistant(MDR) A. veronii. KEY POINTS: • DN6NH2 improved intracellular antibacterial activity against MDR A. veronii. • DN6NH2 entered macrophages by micropinocytosis and enhanced the internalization rates. • DN6NH2 effectively protected the mice from infection with A. veronii.

Characterization of a Lytic Bacteriophage vB_EfaS_PHB08 Harboring Endolysin Lys08 Against Enterococcus faecalis Biofilms.

Enterococcus faecalis is an opportunistic pathogen that causes illnesses ranging from urinary tract infections to sepsis in humans and animals. However, the overuse of antibiotics has increased rates of drug resistance among E. faecalis isolates. Bacteriophages and their derivatives have recently been identified as good candidates for the treatment of drug-resistant bacterial infections. Here, we isolated a virulent E. faecalis phage, PHB08, using the double-layer plate method. The bioactivity of the phage was determined via one-step growth curve testing and bacterial killing assays, and whole-genome sequencing was performed using the Illumina HiSeq platform. In addition, protein expression and antibiofilm assays were performed to investigate the activity of the phage lysin. Results showed that PHB08 has a 55,244-bp linear double-stranded DNA genome encoding 91 putative coding sequences. PHB08 inhibited the growth of host strain EF3964 at 37 °C in tryptic soy broth (TSB) medium, while in vegetable models, PHB08 caused a 4.69-log decrease in viable E. faecalis cells after 24 h. Both PHB08 and its endolysin lys08 showed antibiofilm activity against E. faecalis biofilms, which was enhanced by Mn2+ ions. Thus, virulent phage PHB08 and endolysin lys08 may be good candidates for reducing and/or eradicating E. faecalis infections.

An antimicrobial molecule mitigates signs of sepsis in vivo and eradicates infections from lung tissue.

The peptide sequence KKIRVRLSA was synthesized in a dimeric structure (SET-M33DIM) and evaluated as a candidate drug for infections due to multidrug-resistant (MDR) Gram-negative pathogens. SET-M33DIM showed significant antibacterial activity against MDR strains of Klebsiella pneumoniae, Acinetobacter baumannii, and Escherichia coli (Minimal Inhibitory Concentration [MICs], 1.5-11 µM), and less activity against Pseudomonas aeruginosa (MICs, 11-22 µM). It showed very low toxicity in vitro, ex vivo, and in vivo; in cytotoxicity tests, its EC50 was as much as 22 times better than that of SET-M33, a peptide with the same amino-acid sequence, but synthesized in tetra-branched form (638 vs 28 µM). In in vivo and ex vivo experiments, SET-M33DIM cleared P. aeruginosa infection, significantly reducing signs of sepsis in animals, and restoring cell viability in lung tissue after bacterial challenge. It also quelled inflammation triggered by LPS and live bacterial cells, inhibiting expression of inflammatory mediators in lung tissue, cultured macrophages, and bronchial cells from a cystic fibrosis patient.

Effects of negative-pressure therapy with and without ropivacaine instillation in the early evolution of severe peritonitis in pigs.

The abdomen is the second most common source of sepsis and secondary peritonitis, which likely lead to death. In the present study, we hypothesized that instillation of local anesthetics into the peritoneum might mitigate the systemic inflammatory response syndrome (SIRS) in the open abdomen when combined with negative-pressure therapy (NPT) to treat severe peritonitis. We performed a study in 21 pigs applying a model of sepsis based on ischemia/reperfusion and fecal spread into the peritoneum. The pigs were randomized into three groups, and treated for 6h as follows: Group A: temporary abdominal closure with ABTHERA™ Open Abdomen Negative-Pressure Therapy; Group B: temporary abdominal closure with ABTHERA™ Open Abdomen Negative-Pressure Therapy plus abdominal instillation with physiological saline solution (PSS); and Group C: temporary abdominal closure with ABTHERA™ Open Abdomen Negative-Pressure Therapy plus peritoneal instillation with a solution of ropivacaine in PPS. A comparison between the three groups revealed no statistically significant difference for any of the parameters registered (p > 0.05), i.e., intra-abdominal pressure, blood pressure, heart rate, O2 saturation, diuresis, body temperature, and blood levels of interleukin 6 (IL-6), tumor necrosis factor alpha (TNFα), and c-reactive protein (CRP). In addition, histological studies of the liver, ileum, kidney and lung showed no difference between groups. The use of abdominal instillation (with or without ropivacaine) did not change the effect of 6h of NPT after sepsis in animals with open abdomen. The absence of adverse effects suggests that longer treatments should be tested.

Role of tissue factor in the procoagulant and antibacterial effects of human adipose-derived mesenchymal stem cells during pneumosepsis in mice

BackgroundAdult mesenchymal stem cells (MSCs) improve the host response during experimental sepsis in animals. MSCs from various sources express a procoagulant activity that has been linked to the expression of tissue factor. This study sought to determine the role of tissue factor associated with adipose-derived MSCs (ASCs) in their procoagulant and antibacterial effects during pneumonia-derived sepsis.MethodsMice were infused intravenously with ASCs or vehicle after infection with the common human pathogen Klebsiella pneumoniae via the airways.ResultsInfusion of freshly cultured or cryopreserved ASCs induced the expression of many genes associated with tissue factor signaling and coagulation activation in the lungs. Freshly cultured and cryopreserved ASCs, as well as ASC lysates, exerted procoagulant activity in vitro as determined by a fibrin generation assay, which was almost completely inhibited by an anti-tissue factor antibody. Infusion of cryopreserved ASCs was associated with a rise in plasma thrombin-antithrombin complexes (indicative of coagulation activation) and formation of multiple thrombi in the lungs 4 h post-infusion. Preincubation of ASCs with anti-tissue factor antibody prior to infusion prevented the rise in plasma thrombin-antithrombin complex concentrations but did not influence thrombus formation in the lungs. ASCs reduced bacterial loads in the lungs and liver at 48 h after infection, which was not influenced by preincubation with anti-tissue factor antibody. At this late time point, microthrombi in the lungs were not detected anymore.ConclusionThese data indicate that ASC-associated tissue factor is responsible for systemic activation of coagulation after infusion of ASCs but not for the formation of microthrombi in the lungs or antibacterial effects.

Serum developmental endothelial locus-1 is associated with severity of sepsis in animals and humans

Disruption of the endothelial glycocalyx has a prominent role in the pathophysiology of sepsis. Developmental endothelial locus-1 (Del-1) is an endothelial-derived anti-inflammatory factor. We hypothesized that degradation of the endothelial glycocalyx during sepsis may increase serum Del-1. A mouse model of sepsis was created using cecal ligation and puncture. In septic mice, the endothelial glycocalyx was nearly completely degraded, with less formation of Del-1 in the endothelium and extracellular matrix than in control mice. Serum Del-1 levels were significantly increased in the septic mice with increasing severity of sepsis. Serum Del-1 levels were also measured in 84 patients with sepsis and septic shock and in 20 control subjects. The median serum Del-1 level in patients with sepsis was significantly higher than that in healthy controls. The high Del-1 group had higher illness severity scores and contained more patients with organ dysfunction than the low Del-1 group. The 90-day mortality rate was significantly higher in the high Del-1 group than in the low Del-1 group. Multivariate analysis indicated a tendency for a high serum Del-1 level to be associated with a higher mortality risk. Increased serum Del-1 may be a novel diagnostic biomarker of sepsis and an indicator of disease severity.

Overexpression of Gilz Protects Mice Against Lethal Septic Peritonitis.

Sepsis in humans and experimental animals is characterized by an acute inflammatory response. glucocorticoids (GCs) are widely used for the treatment of many inflammatory disorders, yet their effectiveness in sepsis is debatable. One of the major anti-inflammatory proteins induced by GCs is glucocorticoid-induced leucine zipper (GILZ, coded by the TSC22D3 gene). We found that TSC22D3 mRNA expression is downregulated in white blood cells of human sepsis patients. Interestingly, transgenic GILZ-overexpressing mice (GILZ-tg) showed better survival rates in the cecal ligation and puncture (CLP) model of mouse sepsis. To our surprise, GILZ had only mild anti-inflammatory effects in this model, as the systemic proinflammatory response was not significantly reduced in GILZ-tg mice compared with control mice. During CLP, we observed reduced bacterial counts in blood of GILZ-tg mice compared with control mice. We found increased expression of Tsc22d3 mRNA specifically in peritoneal exudate cells in the CLP model, as well as increased capacity for bacterial phagocytosis of CD45 GILZ-tg cells compared with CD45 GILZ-wt cells. Hence, we believe that the protective effects of GILZ in the CLP model can be linked to a more efficient phagocytosis.

Special aspects of systemic inflammation course in animals.

Aim:In this study, we identified characteristics of systemic inflammation associated with surgical sepsis in animals. We evaluated the role of purine metabolism, functionally associated lipoperoxidation processes of membrane structures, and the antioxidant system in the development of surgical sepsis in dogs.Materials and Methods:Dogs with a provisional exclusion of sepsis were included in the study. The control group (Group 1) included clinically healthy dogs (n=5), and medium-breed dogs with systemic inflammation response syndrome (n=30) were categorized in the experimental group (Group 2). Along with hemogram and biochemical analysis, we determined the amount of malondialdehyde, glutathione, superoxide dismutase, catalase, glutathione reductase, and glucose-6-phosphate dehydrogenase on the 1st and 14th day of the study. Treatment included a thorough reorganization of the septic focus, followed by antibacterial therapy. Sick animals were injected with a drug (dexamethasone) that suppresses the synthesis and inhibits the action of inflammatory mediators. Decompensation of the functions of organs and systems was carried out using symptomatic therapy.Results:We found that enhanced lipid peroxidation of unsaturated fatty acids of membrane structures stimulates the generalization of inflammatory process, as evidenced by the significant deviation from the physiologically normal values of lipid peroxidation, C-reactive protein, blood cell count, etc. The course of systemic inflammation associated with surgical sepsis in animals can be attributed to several consistently developing processes that function as a result of increased purine mononucleotide catabolism, peroxide compound formation, and their excessive breakdown in reactions associated with the consumption of glutathione due to the insufficient recovery of glutathione disulfide.Conclusion:The amount of uric acid, glycosaminoglycans, hyaluronic acid in blood plasma, and the content of malondialdehyde, glutathione, and glutathione reductase in erythrocytes should be considered when assessing the severity of the systemic inflammatory process. The increased glutathione requirement in dogs with surgical sepsis requires intervention with pharmacological agents, and further research is needed in this aspect.

Identification of Pyogenic Bacteria in Human and Animals Conventionally and Non-nucleic Acid Molecularly Using MALDI-TOF MS

Sepsis is considered a race to death between pathogens and host immune system, associated with a high mortality worldwide. Until now, blood cultures (BCs) are still the “gold standard” for identification of pathogens causing sepsis. Its major drawback is long turn around time (TAT) of 24–48 h up to several days, which is not compatible with the need for early sepsis diagnosis. Molecular assays as matrix-assisted laser- desorption ionization time-of-flight mass spectrometry(MALDI-TOF MS) reduce the TAT. Herein, the main aim of the study is to develop rapid and highly sensitive molecular proteomic non-nucleic acid assay for identification (ID) of the most common bacteria causing sepsis and pyogenic infections in human and animals. Eighty clinical samples, including 50 animal pus samples and 30 neonatal whole blood samples were subjected for conventional and molecular identification using VITEK-MS. About 70 % of samples were BC positive, including 33/50(66 %) of animal pus samples and 23/30 (76.7 %) of neonatal blood samples. The identified bacterial species were only three conventionally versus twelve using VITEK-MS, with variable confidence value (C.V) that was 99.9 % for 55/58 (94.8 %) isolates, 50 % for 2/58 (3.4 %) isolates and 26.5 % with 1/58 (1.74 %) isolate. The species-level identification for Streptococci was more challenging than for Staphylococci and Enterococci with only 50 % C.V for S. dysagalactiaesubsp.dysagalactiae. Culture provided concordant species- and genus-level identification with VITEK-MS for 24/58(41.3 %) and 34/58(58.6 %) of isolates, respectively. The overall concordance was 100 % for all isolates except P. aeruginosawas 87.5 %.

Inhibition of NF-κB Pathway with IKK-16 or Linagliptin Attenuates the Cardiac Dysfunction Associated with Polymicrobial Sepsis in Mice with Preexisting Type 2 Diabetes Mellitus (T2DM)

Introduction: Patients with diabetes are more susceptible to infections and sepsis. Activation of nuclear factor-κB (NF-κB) plays a substantial role in the pathophysiology of sepsis and diabetes. Here we investigate i) the effect of preexisting type 2 diabetes mellitus on cardiac dysfunction associated with sepsis and ii) whether inhibition of NF-κB using IKK-16 or linagliptin attenuates cardiac dysfunction in mice with sepsis and diabetes. Methods: Ten-week old male C57BL/6 mice received high fat (HFD) or chow diet for 12 weeks, and were then subjected to caecal ligation and puncture (CLP) or sham surgery for 24 hours. At 1 hour after CLP, mice received IKK-16, linagliptin, or vehicle. Results: Administration of HFD resulted in a significant impairment in glucose tolerance and a small, but significant, reduction in ejection fraction. Immunoblot analysis of hearts tissue showed that HFD caused significant NF-κB pathway activation and expression of inducible nitric oxide synthase (iNOS). Mice on HFD subjected to CLP showed further (i) decline in EF, (ii) increase in NF-κB pathway activation, (iii) increase in iNOS expression, (iv) an increase in serum ALT, and (v) a significant renal dysfunction. Treatment of HFD-CLP mice with IKK-16 or linagliptin resulted in significant reduction of the CLP-induced i) cardiac dysfunction, ii) NF-κB pathway activation, and iii) iNOS expression when compared to mice treated with vehicle. Conclusion: Our results show that HFD results in inflammation and cardiac dysfunction. Moreover, a preexisting diabetic phenotype worsened the cardiac dysfunction associated with CLP-sepsis. Most notably, inhibition of NF-κB reduced the cardiac dysfunction caused by sepsis in animals with preexisting T2DM. Disclosure S. Al Zoubi: None. J. Chen: None. L. Martin: None. C. Murphy: None. G.S. Purvis: None. F. Chiazza: Other Relationship; Self; Boehringer Ingelheim GmbH. D. Collotta: None. M. Collino: None. C. Thiemermann: None.

Fructose-1,6-bisphosphate preserves glucose metabolism integrity and reduces reactive oxygen species in the brain during experimental sepsis

Sepsis is one of the main causes of hospitalization and mortality in Intensive Care Units. One of the first manifestations of sepsis is encephalopathy, reported in up to 70% of patients, being associated with higher mortality and morbidity. The factors that cause sepsis-associated encephalopathy (SAE) are still not well known, and may be multifactorial, as perfusion changes, neuroinflammation, oxidative stress and glycolytic metabolism alterations. Fructose-1,6-bisphosphate (FBP), a metabolite of the glycolytic route, has been reported as neuroprotective agent. The present study used an experimental sepsis model in C57BL/6 mice. We used in vivo brain imaging to evaluate glycolytic metabolism through microPET scans and the radiopharmaceutical 18F-fluoro-2-deoxy-D-glucose (18F-FDG). Brain images were obtained before and 12 h after the induction of sepsis in animals with and without FBP treatment. We also evaluated the treatment effects in the brain oxidative stress by measuring the production of reactive oxygen species (ROS), the activity of catalase (CAT) and glutathione peroxidase (GPx), and the levels of fluorescent marker 2′7′-dichlorofluorescein diacetate (DCF). There was a significant decrease in brain glucose metabolism due to experimental sepsis. A significant protective effect of FBP treatment was observed in the cerebral metabolic outcomes. FBP also modulated the production of ROS, evidenced by reduced CAT activity and lower levels of DCF. Our results suggest that FBP may be a possible candidate in the treatment of SAE.

Endothelial biomarkers in human sepsis: pathogenesis and prognosis for ARDS.

Experimental models of sepsis in small and large animals and a variety of in vitro preparations have established several basic mechanisms that drive endothelial injury. This review is focused on what can be learned from the results of clinical studies of plasma biomarkers of endothelial injury and inflammation in patients with sepsis. There is excellent evidence that elevated plasma levels of several biomarkers of endothelial injury, including von Willebrand factor antigen (VWF), angiopoietin-2 (Ang-2), and soluble fms-like tyrosine kinase 1 (sFLT-1), and biomarkers of inflammation, especially interleukin-8 (IL-8) and soluble tumor necrosis factor receptor (sTNFr), identify sepsis patients with a higher mortality. There are also some data that elevated levels of endothelial biomarkers can identify which patients with non-pulmonary sepsis will develop acute respiratory distress syndrome (ARDS). If ARDS patients are divided among those with indirect versus direct lung injury, then there is an association of elevated levels of endothelial biomarkers in indirect injury and markers of inflammation and alveolar epithelial injury in patients with direct lung injury. New research suggests that the combination of biologic and clinical markers may make it possible to segregate patients with ARDS into hypo- versus hyper-inflammatory phenotypes that may have implications for therapeutic responses to fluid therapy. Taken together, the studies reviewed here support a primary role of the microcirculation in the pathogenesis and prognosis of ARDS after sepsis. Biological differences identified by molecular patterns could explain heterogeneity of treatment effects that are not explained by clinical factors alone.

NMR-Based Plasma Metabolomics at Set Intervals in Newborn Dairy Calves with Severe Sepsis.

The aim of this first study was to reveal the new potential biomarkers by a metabolomics approach in severe septic calves. Sepsis is a common cause of morbidity and mortality in newborn dairy calves. The main challenges with the use of biomarkers of sepsis in domestic animals are their availability, cost, and time required to obtain a result. Metabolomics may offer the potential to identify biomarkers that define calf sepsis in terms of combined clinical, physiological, and pathobiological abnormalities. To our knowledge, this is the first study presenting an NMR- (nuclear magnetic resonance-) based plasma metabolomics at set intervals in neonatal septic calves. Twenty neonatal dairy calves with severe sepsis and ten healthy calves were used. Hematological and biochemical health profiles were gathered in plasma samples at set intervals. Similarly, NMR spectra were acquired. All diseased animals (except one) died after 72 hours. Clinical and laboratory results were in accordance with those of severe septic animals. Multivariate analysis on NMR plasma spectra proved to be an excellent tool for faster identification of calves with severe sepsis from healthy animals. The NMR-based metabolomic profile may contribute to the better understanding of severe sepsis in newborn calves.

Successful Treatment of Severe Tungiasis in Pigs Using a Topical Aerosol Containing Chlorfenvinphos, Dichlorphos and Gentian Violet.

BackgroundIn endemic communities, zoonotic tungiasis, a severe skin disease caused by penetrating female sand fleas, is a public health hazard causing significant human and animal morbidity. No validated drugs are currently available for treatment of animal tungiasis. Due to the reservoir in domestic animals, integrated management of human and animal tungiasis is required to avert its negative effects.Methods and principal findingsA topical aerosol containing chlorfenvinphos 4.8%, dichlorphos 0.75% and gentian violet 0.145% licensed to treat tick infestations, myiasis and wound sepsis in animals in the study area, was tested for its potential tungicidal effects in a randomized controlled field trial against pig tungiasis in rural Uganda. Animals with at least one embedded flea were randomized in a treatment (n = 29) and a control (n = 26) group. One week after treatment, 58.6% of the treated pigs did not show any viable flea lesion whereas all control pigs had at least one viable lesion. After treatment the number of viable lesions (treated median = 0, overall range = 0–18 vs. control median = 11.5, range = 1–180) and the severity score for estimating acute pathology in pig tungiasis (treated median = 1, range = 0–3.5 vs. control median = 7, range = 0–25) were significantly lower in treated than in control pigs (p < 0.001). In the treatment group the median number of viable flea lesions decreased from 8.5 to 0 (p < 0.001). Similarly, the median acute severity score dropped from 6 to 1 (p < 0.001). Every pig in the treatment group showed a decrease in the number of viable fleas and tungiasis-associated acute morbidity while medians for both increased in the control group.ConclusionsThe study demonstrates that a topical treatment based on chlorfenvinphos, dichlorphos and gentian violet is highly effective against pig tungiasis. Due to its simplicity, the new approach can be used for the treatment of individual animals as well as in mass campaigns.

Co-morbidity and systemic inflammation as drivers of cognitive decline: new experimental models adopting a broader paradigm in dementia research.

Dementia prevalence increases with age and Alzheimer’s disease (AD) accounts for up to 75% of cases. However, significant variability and overlap exists in the extent of amyloid-β and Tau pathology in AD and non-demented populations and it is clear that other factors must influence progression of cognitive decline, perhaps independent of effects on amyloid pathology. Coupled with the failure of amyloid-clearing strategies to provide benefits for AD patients, it seems necessary to broaden the paradigm in dementia research beyond amyloid deposition and clearance. Evidence has emerged from alternative animal model approaches as well as clinical and population epidemiological studies that co-morbidities contribute significantly to neurodegeneration/cognitive decline and systemic inflammation has been a strong common theme in these approaches. We hypothesise, and discuss in this review, that a disproportionate inflammatory response to infection, injury or chronic peripheral disease is a key determinant of cognitive decline. We propose that detailed study of alternative models, which encompass acute and chronic systemic inflammatory co-morbidities, is an important priority for the field and we examine the cognitive consequences of several of these alternative experimental approaches. Experimental models of severe sepsis in normal animals or moderate acute systemic inflammation in animals with existing neurodegenerative pathology have uncovered roles for inflammatory mediators interleukin-1β, tumour necrosis factor-α, inducible nitric oxide synthase, complement, prostaglandins and NADPH oxidase in inflammation-induced cognitive dysfunction and neuronal death. Moreover, microglia are primed by existing neurodegenerative pathology to produce exaggerated responses to subsequent stimulation with bacterial lipopolysaccharide or other inflammatory stimuli and these insults drive acute dysfunction and negatively affect disease trajectory. Chronic co-morbidities, such as arthritis, atherosclerosis, obesity and diabetes, are risk factors for subsequent dementia and those with high inflammatory status are particularly at risk. Models of chronic co-morbidities, and indeed low grade systemic inflammation in the absence of specific pathology, indicate that interleukin-1β, tumour necrosis factor-α and other inflammatory mediators drive insulin resistance, hypothalamic dysfunction, impaired neurogenesis and cognitive function and impact on functional decline. Detailed study of these pathways will uncover important mechanisms of peripheral inflammation-driven cognitive decline and are already driving clinical initiatives to mitigate AD progression through minimising systemic inflammation.