Inflammation and coagulation. An overview

General mechanisms of coagulation and targets of anticoagulants (Section I)

Contrary to previous models based on plasma, coagulation processes are currently believed to be mostly cell surface-based, including three overlapping phases: initiation, when tissue factor-expressing cells and microparticles are exposed to plasma; amplification, whereby small amounts of thrombin induce platelet activation and aggregation, and promote activation of factors (F)V, FVIII and FXI on platelet surfaces; and propagation, in which the Xase (tenase) and prothrombinase complexes are formed, producing a burst of thrombin and the cleavage of fibrinogen to fibrin. Thrombin exerts a number of additional biological actions, including platelet activation, amplification and self-inhibition of coagulation, clot stabilisation and anti-fibrinolysis, in processes occurring in the proximity of vessel injury, tightly regulated by a series of inhibitory mechanisms. ″Classical″ anticoagulants, including heparin and vitamin K antagonists, typically target multiple coagulation steps. A number of new anticoagulants, already developed or under development, target specific steps in the process, inhibiting a single coagulation factor or mimicking natural coagulation inhibitors.

Effect of alcohol intoxication on the risk of venous thromboembolism: A nationwide retrospective cohort study

This study investigated whether alcohol intoxication (AI) increases the risk of venous thromboembolism (VTE) by using the Taiwan National Health Insurance Research Database (NHIRD).Using data from the NHIRD, we assembled 61,229 patients with acute AI and randomly selected 244,916 controls. Each patient was monitored from 2000 to 2011 to identify those who were subsequently diagnosed with deep vein thrombosis (DVT) and pulmonary embolism (PE). Cox proportional hazard regression analysis was conducted to determine the risk of VTE in the patients with AI compared with the controls.The incidence rate of DVT during the 10 years follow-up period was 9.36 per 10,000 person-years and 2.07 per 10,000 person-years in the AI and non-AI cohorts, respectively. Moreover, the incidence rate of PE was 4 per 10,000 person-years in the AI cohort and 0.93 in the non-AI cohort. After adjustment for age, sex, and comorbidities, the risks of DVT and PE were 3.40 [95% confidence interval (CI) = 2.83-4.08] and 3.53 (95% CI = 2.69-4.65)-fold higher in the AI cohort than in the non-AI cohort.An increased incidence of VTE was observed among patients with AI. Therefore, physicians should carefully estimate the risk of VTE in patients with AI.

Rapid Source-Control Laparotomy: Is There a Mortality Benefit?

BACKGROUND

The purpose of this study was to determine the influence rapid source-control laparotomy (RSCL) has on the mortality rate in non-trauma patients with intra-abdominal infection. The hypothesis was that RSCL reduces deaths and hospital lengths of stay (LOS) in patients compared with definitive repair and primary fascial closure (PFC).

METHODS

The International Classification of Diseases-10 codes for sepsis, gastric and duodenal ulcer perforation or hemorrhage, incisional or ventral hernia with obstruction, intestinal volvulus, ileus with obstruction, diverticulitis with perforation or abscess, vascular disorder of intestine, non-traumatic intestinal perforation, peritoneal abscess, and unspecified peritonitis were used to query the 2015 National Surgical Quality Improvement Project (NSQIP) database for all patients treated with either RSCL or PFC. The two groups of patients were compared on the basis of LOS and deaths. Collected data included age, gender, body mass index (BMI), site classification, American Society of Anesthesiologists (ASA) class, operative time, number of risk factors, and pre-operative septic state.

RESULTS

After adjusting for the aforementioned variables, propensity score-matched cohorts (n = 210 in each cohort) were used to evaluate the influence of incision closure type on LOS and mortality rate. The odds of death (31.4% vs. 21.4%) with RSCL was 1.78 (95% confidence interval 1.08-2.95; p = 0.02) times that of PFC. Closure type was not significantly associated with an increased LOS (median 14 vs. 11 days; p = 0.35).

CONCLUSIONS

This retrospective cohort analysis demonstrated that RSCL is associated with higher odds of death in general surgical patients with intra-abdominal infection. There is a need for further studies to delineate what, if any, physiologic parameters indicate a need for RSCL.

Inflammatory Markers Are Positively Associated with Serum trans-Fatty Acids in an Adult American Population

BACKGROUND AND AIM

The relationship between serum trans-fatty acids (TFAs) and systemic inflammation markers is unclear. We investigated the association of serum TFAs with high sensitivity C-reactive protein (hs-CRP) and fibrinogen in adult Americans.

METHODS

The 1999 to 2000 National Health and Nutrition Examination Survey (NHANES) participants with measured data on hs-CRP and fibrinogen were included. TFAs were measured via capillary gas chromatography and mass spectrometry using negative chemical ionization. Analysis of covariance and multivariable-adjusted linear regression models were used to investigate the associations between these parameters, accounting for the survey design.

RESULTS

Of the 5446 eligible participants, 46.8% (n = 2550) were men. The mean age was 47.1 years overall: 47.8 years in men and 46.5 years in women (p = 0.085). After adjustment for age and sex, mean serum TFAs rose with the increasing quarters of hs-CRP and fibrinogen (both p < 0.001). In linear regression models adjusted for age, sex, race, education, marital status, body mass index, and smoking, serum TFAs were an independent predictor of plasma hs-CRP and fibrinogen levels.

CONCLUSION

A high level of TFAs appears to be a contributor to an unfavourable inflammatory profile. Because serum TFAs concentrations are affected by dietary TFA intake, these data suggest a possible contribution of TFAs intake modulation in the prevention of inflammation-related chronic diseases.

Immune-inflammatory activation after a single laparotomy in a rat model: effect of adenosine, lidocaine and Mg2+ infusion to dampen the stress response

Our aim was to examine the effect of low-volume 0.9% NaCl adenosine, lidocaine and Mg2+ (ALM) ‘drip’ on early immune-inflammatory activation after a single laparotomy with no further manipulation. Male Sprague–Dawley rats were anesthetized and randomly assigned to one of the groups, baseline, 1 h infusion 0.9% NaCl ± ALM and metrics, 1 h infusion and 6-h metrics, and 6 h continuous infusion and metrics. Complete blood count, acid–base balance, systemic levels of IL-6 and IL-10, and coagulation status were measured. After 1 h, there was a disproportionate increase in circulating neutrophils between saline and ALM groups despite an identical 45% fall in lymphocytes. Disproportionate increases also occurred in platelet counts 1 h after surgery, and saline controls had increased respiratory alkalosis at 6 h with higher lactate. Systemic inflammation was also evident after 1 h in both groups (plasma IL-6 increase) and was amplified in saline-controls after 6 h. The ALM group increased anti-inflammatory cytokine IL-10. Surgery was not associated with acute coagulopathy; however, there were significant reductions in fibrinolysis. Following a single laparotomy, ALM infusion appeared to reduce stress-induced release of neutrophils and platelets into the circulation, and reduced acid–base disturbance. After 1 h, both groups had similar IL-6 levels, but ALM animals had increased IL-10, indicating improved inflammatory balance. The uncoupling of inflammation and coagulation activation but not fibrinolysis may offer a unique opportunity to investigate differential activation of innate immunity in response to sterile injury in this model.

Cutaneous lupus erythematosus and the risk of deep venous thrombosis and pulmonary embolism: A Danish nationwide cohort study

Background

Venous thromboembolism (VTE) is a major public health concern. Lupus erythematosus (LE) is a chronic autoimmune disease ranging from localized cutaneous disease (CLE) to systemic involvement (SLE). Patients with SLE have an increased risk of venous thromboembolism (VTE), but little is known about the CLE-related risk of VTE.

Methods

To evaluate the risk of VTE in patients with SLE and CLE as compared to the general population, a retrospective cohort study was conducted. Incidence rates and hazard ratios (HRs) with 95% confidence intervals (CIs) from multivariable Cox regression models were used to evaluate and compare the risk of VTE. Registries of hospitalizations, outpatient visits, and prescription drug use were studied to determine the risk of VTE in patients with CLE and SLE and the general population between 1997 and 2011.

Results

A total of 3234 patients with CLE and 3627 patients with SLE were identified and compared to 5,590,070 individuals in the reference population. The incidence rates per 1000 year of VTE were higher in patients with LE, i.e. 1.20, 3.06, and 5.24 for the reference population, CLE, and SLE, respectively. In adjusted models, both CLE (HR 1.39; 95% CI 1.10–1.78) and SLE (HR 3.32; 95% CI 2.73–4.03) were associated with a statistically significant increased risk of VTE, compared to the reference population.

Conclusion

In this nationwide study, both CLE and SLE were significant risk factors for VTE. The results add to our understanding of comorbidities in patients with LE, and call for further studies and increased awareness of thromboembolic complications in patients with CLE.

Angiotensin II promotes the anticoagulant effects of rivaroxaban via angiotensin type 2 receptor signaling in mice

Rivaroxaban is an oral direct factor Xa inhibitor approved for the treatment of stroke and systemic thromboembolism in patients with non-valvular atrial fibrillation. Despite its efficacy, rivaroxaban therapy results in adverse effects and complications, such as bleeding. Angiotensin II (AngII) is implicated in many cardiovascular conditions, such as hypertension and heart failure. In this study, we investigate whether AngII influences anticoagulant effects of rivaroxaban by using an experimental mouse model with type 2 diabetes mellitus and advanced glycation end product (AGE)-exposed human umbilical vein endothelial cells (HUVECs). We found that AngII promoted the anticoagulant effects of rivaroxaban in KKAy mice. The combination of rivaroxaban and AngII enhanced in vivo tissue factor pathway inhibitor (TFPI) activity and induced TFPI expression and activity in AGE-exposed HUVECs. Angiotensin type 2 receptor (AT2R) and Mas antagonists attenuated the AngII-enhanced anticoagulant action of rivaroxaban in vivo, and abolished the increased endothelial TFPI expression and activity. However, angiotensin type 1 receptor (AT1R) antagonist exerted no effects. Additionally, combination of rivaroxaban and AngII induced aortic AT2R and Mas expression. Our data suggest that the anticoagulant effects of rivaroxaban are promoted by AngII via AT2R and Mas signaling. These findings are significant for the clinical administration of rivaroxaban.

Effects of IL-1β, IL-6 and IL-8 on erythrocytes, platelets and clot viscoelasticity

Complex interactions exist between cytokines, and the interleukin family plays a fundamental role in inflammation. Particularly circulating IL-1β, IL-6 and IL-8 are unregulated in systemic and chronic inflammatory conditions. Hypercoagulability is an important hallmark of inflammation, and these cytokines are critically involved in abnormal clot formation, erythrocyte pathology and platelet hyper-activation, and these three cytokines have known receptors on platelets. Although these cytokines are always unregulated in inflammation, we do not know how the individual cytokines act upon the structure of erythrocytes and platelets, and which of the viscoelastic clot parameters are changed. Here we study the effects of IL-1β, IL-6 and IL-8 at low physiological levels, representative of chronic inflammation, by using scanning electron microscopy and thromboelastography. All three interleukins caused the viscoelastic properties to display an increased hypercoagulability of whole blood and pathology of both erythrocytes and platelets. The most pronounced changes were noted where all three cytokines caused platelet hyper-activation and spreading. Erythrocyte structure was notably affected in the presence of IL-8, where the morphological changes resembled that typically seen in eryptosis (programmed cell death). We suggest that erythrocytes and platelets are particularly sensitive to cytokine presence, and that they are excellent health indicators.

Associations Between Inflammatory Markers, Hemostatic Markers, and Microvascular Complications in 182 Chinese Patients With Type 2 Diabetes Mellitus

OBJECTIVE

To examine the associations between inflammatory markers, coagulation and fibrinolysis parameters, and microvascular complications in 182 Chinese patients with type 2 diabetes mellitus (T2DM) who sought treatment at a large hospital in Zhejiang province, China.

METHODS

We investigated the relationships of blood inflammatory markers with hemostatic markers in 87 patients with T2DM who did not have complications and 95 patients with T2DM who had microvascular complications.

RESULTS

C-reactive protein (CRP) and interleukin-6 (IL-6) were significantly correlated with fibrinogen, thrombin-antithrombin III complex (TAT III), plasminogen activator inhibitor-1 (PAI-1), von Willebrand factor (vWF), and coagulation factors (F) VII in patients with T2DM who had microvascular complications (P <.05). Based on logistic regression analysis, the highest-tertile groups of fibrinogen, FVII, and FVIII, corresponded to a greater risk of high CRP, whereas risk of high IL-6 was significantly greater in the groups with highest-tertile values for fibrinogen, FVII, TAT III, PAI-1, and activated protein C (APC).

CONCLUSIONS

Elevated levels of CRP and IL-6 might be associated with increased coagulability and a tendency towards thrombus formation in patients with T2DM who have microvascular complications.

Emerging targets for treating sulfur mustard-induced injuries

Sulfur mustard (SM; bis-(2-chlororethyl) sulfide) is a highly reactive, potent warfare agent that has recently reemerged as a major threat to military and civilians. Exposure to SM is often fatal, primarily due to pulmonary injuries and complications caused by its inhalation. Profound inflammation, hypercoagulation, and oxidative stress are the hallmarks that define SM-induced pulmonary toxicities. Despite advances, effective therapies are still limited. This current review focuses on inflammatory and coagulation pathways that influence the airway pathophysiology of SM poisoning and highlights the complexity of developing an effective therapeutic target.

Intravenous Immunoglobulin Responsive Persistent Thrombocytopenia after Dengue Haemorrhagic Fever

Dengue outbreak is common in Indian subcontinent and causes significant morbidity and mortality. Year 2015 has witnessed yet another Dengue epidemic in northern India and the number of cases this year is maximum in a decade. Dengue infection is a viral disease and there are 4 different serotypes DENV1, DENV2, DENV3 and DENV4. This year DENV2 and DENV4 have been isolated from most of the patients. Thrombocytopenia is hallmark of dengue infection and generally recovers within ten days of onset of symptoms. We report a case of dengue haemorrhagic fever in which thrombocytopenia persisted for almost a month and improved after Intravenous immunoglobulin (IVIG) administration. This is the first case where IVIG has been successfully used for treating persisting thrombocytopenia after dengue infection.

Endometriosis-Derived Stromal Cells Secrete Thrombin and Thromboxane A2, Inducing Platelet Activation

Platelets have been recently revealed to play important roles in the development of endometriosis. However, it is unclear whether endometriotic lesions can secrete any platelet inducers outside the menstruation window. Hence, this study was undertaken to see whether endometriosis-derived stromal cells secrete platelet activators and cause platelet activation. We employed in vitro experimentation using primary ectopic endometrial stromal cells (EESCs) and platelets from healthy male volunteers and evaluated the extent of platelet aggregation by aggregometer and the platelet activation rate by flow cytometry using supernatants harvested from EESCs of different cell densities. We also measured the concentration of thromboxane B2 (TXB2), a metabolite of thromboxane A2 (TXA2), and thrombin activity in supernatants harvested from EESCs of different densities and evaluated the extent of platelet aggregation after treatment of EESCs with hirudin, Ozagrel, and apyrase. Finally, the concentration of TXB2, thrombin, and transforming growth factor β1 (TGF-β1) in platelets cocultured with different densities of EESCs is measured by enzyme-linked immunosorbent assay. We found that EESCs secrete thrombin and TXA2 and induce platelet activation and aggregation in a density-dependent fashion. Treatment of platelets with EESCs resulted in increased concentration of TXB2, thrombin, and TGF-β1 in a density-dependent manner. Treatment of EESCs with hirudin and Ozagrel, but not apyrase, resulted in significant suppression of platelet aggregation. Thus, given recently reported effects of activated platelets on the cell behaviors of EESCs and endometriotic lesions in general, our findings establish that endometriotic lesions and platelets engage active cross-talks in the development of endometriosis, highlighting the importance of lesion microenvironment in endometriosis.

Tranexamic acid in life-threatening military injury and the associated risk of infective complications

BACKGROUND

Tranexamic acid (TXA) has been shown to reduce mortality from severe haemorrhage. Although recent data suggest that TXA has anti-inflammatory properties, few analyses have investigated the impact of TXA on infectious complications in injured patients. The aim was to examine the association between TXA administration and infection risk among injured military personnel.

METHODS

Patients who received TXA were matched by Injury Severity Score with patients who did not receive TXA. Conditional logistic regression was used to examine risk factors associated with infections within 30 days. A Cox proportional analysis evaluated risk factors in a time-to-first-infection model.

RESULTS

A total of 335 TXA recipients were matched with 626 patients who did not receive TXA. A greater proportion of TXA recipients had an infection compared with the comparator group (P < 0·001). Univariable analysis estimated an unadjusted odds ratio (OR) of 2·47 (95 per cent c.i. 1·81 to 3·36) for the association between TXA and infection risk; however, TXA administration was not significant in multivariable analysis (OR 1·27, 0·85 to 1·91). Blast injuries, intensive care unit (ICU) admission, and receipt of 10 units or more of blood within 24 h after injury were independently associated with infection risk. The Cox proportional model confirmed the association with ICU admission and blood transfusion. Traumatic amputations were also significantly associated with a reduced time to first infection.

CONCLUSION

In life-threatening military injuries matched for injury severity, TXA recipients did not have a higher risk of having infections nor was the time to develop infections shorter than in non-recipients. Extent of blood loss, blast injuries, extremity amputations and ICU stay were associated with infection.

Conservation of the Host-Interacting Proteins Tp0750 and Pallilysin among Treponemes and Restriction of Proteolytic Capacity to Treponema pallidum

The spirochete Treponema pallidum subsp. pallidum is the causative agent of syphilis, a chronic, sexually transmitted infection characterized by multiple symptomatic and asymptomatic stages. Although several other species in the genus are able to cause or contribute to disease, T. pallidum differs in that it is able to rapidly disseminate via the bloodstream to tissue sites distant from the site of initial infection. It is also the only Treponema species able to cross both the blood-brain and placental barriers. Previously, the T. pallidum proteins, Tp0750 and Tp0751 (also called pallilysin), were shown to degrade host proteins central to blood coagulation and basement membrane integrity, suggesting a role for these proteins in T. pallidum dissemination and tissue invasion. In the present study, we characterized Tp0750 and Tp0751 sequence variation in a diversity of pathogenic and nonpathogenic treponemes. We also determined the proteolytic potential of the orthologs from the less invasive species Treponema denticola and Treponema phagedenis. These analyses showed high levels of sequence similarity among Tp0750 orthologs from pathogenic species. For pallilysin, lower levels of sequence conservation were observed between this protein and orthologs from other treponemes, except for the ortholog from the highly invasive rabbit venereal syphilis-causing Treponema paraluiscuniculi. In vitro host component binding and degradation assays demonstrated that pallilysin and Tp0750 orthologs from the less invasive treponemes tested were not capable of binding or degrading host proteins. The results show that pallilysin and Tp0750 host protein binding and degradative capability is positively correlated with treponemal invasiveness.

Effects of gabexate mesilate on coagulopathy and organ dysfunction in rats with endotoxemia: a potential use of thrombelastography in endotoxin-induced sepsis

Sepsis and its associated multiple organ failure are related to high mortality in critical patients. Several studies have reported that gabexate mesilate, a synthetic inhibitor of trypsin-like serine protease, protects tissues/organs against injury in the models of endotoxemia. The aim of this study was to examine whether gabexate mesilate could attenuate coagulopathy and organ dysfunction in lipopolysaccharide (LPS)-induced sepsis model by using thrombelastography (TEG). LPS (7.5  mg/kg/h, intravenouly for 4  h) was administered to male adult Wistar rats. Some of the LPS rats received a continuous infusion of gabexate mesilate (10  mg/kg/h, intravenously for 8.5  h) for 30  min before the LPS administration. Variable parameters of hemodynamics, biochemistry, hemostasis and inflammatory response were measured for 6  h after the LPS infusion. TEG variables (R-time, K-time, α-angle, and maximal amplitude) were also measured. The pretreatment of LPS rats with gabexate mesilate significantly attenuated the lung, liver and kidney dysfunction, consumptive coagulopathy, the increases in serum tumor necrosis factor-α, interleukin-6, plasma thrombin-antithrombin complex and plasminogen activator inhibitor-1, and neutrophils infiltration score in lung, liver and kidney, compared with the LPS alone group. In addition, TEG parameters correlated with tissue and liver injury in the late phase of endotoxemia. In particular, a strong negative correlation between maximal amplitude at 4  h and Ln (lactate dehydrogenase) at 6  h after LPS infusion was noted (r = -0.752, P < 0.001, R = 0.566). These results indicate that beneficial effects of anticoagulants (e.g. gabexate mesilate) in endotoxemia could be monitored by TEG per se.

The simultaneous occurrence of both hypercoagulability and hypofibrinolysis in blood and serum during systemic inflammation, and the roles of iron and fibrin(ogen)

Although the two phenomena are usually studied separately, we summarise a considerable body of literature to the effect that a great many diseases involve (or are accompanied by) both an increased tendency for blood to clot (hypercoagulability) and the resistance of the clots so formed (hypofibrinolysis) to the typical, 'healthy' or physiological lysis. We concentrate here on the terminal stages of fibrin formation from fibrinogen, as catalysed by thrombin. Hypercoagulability goes hand in hand with inflammation, and is strongly influenced by the fibrinogen concentration (and vice versa); this can be mediated via interleukin-6. Poorly liganded iron is a significant feature of inflammatory diseases, and hypofibrinolysis may change as a result of changes in the structure and morphology of the clot, which may be mimicked in vitro, and may be caused in vivo, by the presence of unliganded iron interacting with fibrin(ogen) during clot formation. Many of these phenomena are probably caused by electrostatic changes in the iron-fibrinogen system, though hydroxyl radical (OH˙) formation can also contribute under both acute and (more especially) chronic conditions. Many substances are known to affect the nature of fibrin polymerised from fibrinogen, such that this might be seen as a kind of bellwether for human or plasma health. Overall, our analysis demonstrates the commonalities underpinning a variety of pathologies as seen in both hypercoagulability and hypofibrinolysis, and offers opportunities for both diagnostics and therapies.

Viscoelasticity and Ultrastructure in Coagulation and Inflammation: Two Diverse Techniques, One Conclusion

The process of blood clotting has been studied for centuries. A synopsis of current knowledge pertaining to haemostasis and the blood components, including platelets and fibrin networks which are closely involved in coagulation, are discussed. Special emphasis is placed on tissue factor (TF), calcium and thrombin since these components have been implicated in both the coagulation process and inflammation. Analysis of platelets and fibrin morphology indicate that calcium, tissue factor and thrombin at concentrations used during viscoelastic analysis (with thromboelastography or TEG) bring about alterations in platelet and fibrin network ultrastructure, which is similar to that seen in inflammation. Scanning electron microscopy indicated that, when investigating platelet structure in disease, addition of TF, calcium or thrombin will mask disease-induced alterations associated with platelet activation. Therefore, washed platelets without any additives is preferred for morphological analysis. Furthermore, morphological and viscoelastic analysis confirmed that thrombin activation is the preferred method of fibrin activation when investigating fibrin network ultrastructure.

Platelet activation and aggregation promote lung inflammation and influenza virus pathogenesis

RATIONALE

The hallmark of severe influenza virus infection is excessive inflammation of the lungs. Platelets are activated during influenza, but their role in influenza virus pathogenesis and inflammatory responses is unknown.

OBJECTIVES

To determine the role of platelets during influenza A virus infections and propose new therapeutics against influenza.

METHODS

We used targeted gene deletion approaches and pharmacologic interventions to investigate the role of platelets during influenza virus infection in mice.

MEASUREMENTS AND MAIN RESULTS

Lungs of infected mice were massively infiltrated by aggregates of activated platelets. Platelet activation promoted influenza A virus pathogenesis. Activating protease-activated receptor 4, a platelet receptor for thrombin that is crucial for platelet activation, exacerbated influenza-induced acute lung injury and death. In contrast, deficiency in the major platelet receptor glycoprotein IIIa protected mice from death caused by influenza viruses, and treating the mice with a specific glycoprotein IIb/IIIa antagonist, eptifibatide, had the same effect. Interestingly, mice treated with other antiplatelet compounds (antagonists of protease-activated receptor 4, MRS 2179, and clopidogrel) were also protected from severe lung injury and lethal infections induced by several influenza strains.

CONCLUSIONS

The intricate relationship between hemostasis and inflammation has major consequences in influenza virus pathogenesis, and antiplatelet drugs might be explored to develop new antiinflammatory treatment against influenza virus infections.

Activation of the Intrinsic Coagulation Pathway in Patients With Chronic Urticaria

Purpose

Although coagulation activation has been reported in chronic urticaria, data pertaining to detailed changes in coagulation factors and global coagulation status are lacking. The current study evaluated global coagulation status in patients with chronic urticaria using thrombin generation assay (TGA) and the levels of individual coagulation factors.

Methods

Patients with chronic urticaria (n=57) and 20 healthy controls were enrolled. TGA was performed under stimulation with 2 concentrations of tissue factor (TF). Coagulation factors and conventional coagulation assays were also analyzed.

Results

Although patients with chronic urticaria showed prolonged activated partial thromboplastin time, prothrombin time did not differ significantly between patients and controls. In both 1 pM and 5 pM TF-stimulated TGA, peak thrombin and endogenous thrombin potential (ETP) levels were markedly decreased in patients with chronic urticaria. As expected, intrinsic coagulation factors (VIII, IX, and XII), as well as coagulation factors of the common pathway (II, V, and X), were consistently decreased. Additionally, D-dimer was significantly increased in patients as compared to controls. In multivariate regression analysis, the presence of chronic urticaria was the only significant independent contributor to the low ETP value.

Conclusions

Chronic urticaria is characterized by in vivo coagulation activation through the intrinsic coagulation pathway, which can be measured with sensitivity using TGA.

Thrombocytopenia in Dengue: Interrelationship between Virus and the Imbalance between Coagulation and Fibrinolysis and Inflammatory Mediators

Dengue is an infectious disease caused by dengue virus (DENV). In general, dengue is a self-limiting acute febrile illness followed by a phase of critical defervescence, in which patients may improve or progress to a severe form. Severe illness is characterized by hemodynamic disturbances, increased vascular permeability, hypovolemia, hypotension, and shock. Thrombocytopenia and platelet dysfunction are common in both cases and are related to the clinical outcome. Different mechanisms have been hypothesized to explain DENV-associated thrombocytopenia, including the suppression of bone marrow and the peripheral destruction of platelets. Studies have shown DENV-infected hematopoietic progenitors or bone marrow stromal cells. Moreover, anti-platelet antibodies would be involved in peripheral platelet destruction as platelets interact with endothelial cells, immune cells, and/or DENV. It is not yet clear whether platelets play a role in the viral spread. Here, we focus on the mechanisms of thrombocytopenia and platelet dysfunction in DENV infection. Because platelets participate in the inflammatory and immune response by promoting cytokine, chemokine, and inflammatory mediator secretion, their relevance as "immune-like effector cells" will be discussed. Finally, an implication for platelets in plasma leakage will be also regarded, as thrombocytopenia is associated with clinical outcome and higher mortality.

Nicorandil prevents sirolimus-induced production of reactive oxygen species, endothelial dysfunction, and thrombus formation

Sirolimus (SRL) is widely used to prevent restenosis after percutaneous coronary intervention. However, its beneficial effect is hampered by complications of thrombosis. Several studies imply that reactive oxygen species (ROS) play a critical role in endothelial dysfunction and thrombus formation. The present study investigated the protective effect of nicorandil (NIC), an anti-angina agent, on SRL-associated thrombosis. In human coronary artery endothelial cells (HCAECs), SRL stimulated ROS production, which was prevented by co-treatment with NIC. The preventive effect of NIC on ROS was abolished by 5-hydroxydecanoate but not by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one. NIC also inhibited SRL-induced up-regulation of NADPH oxidase subunit p22(phox) mRNA. Co-treatment with NIC and SRL significantly up-regulated superoxide dismutase 2. NIC treatment significantly improved SRL-induced decrease in viability of HCAECs. The functional relevance of the preventive effects of NIC on SRL-induced ROS production and impairment of endothelial viability was investigated in a mouse model of thrombosis. Pretreatment with NIC inhibited the SRL-induced acceleration of FeCl3-initiated thrombus formation and ROS production in the testicular arteries of mice. In conclusion, NIC prevented SRL-induced thrombus formation, presumably due to the reduction of ROS and to endothelial protection. The therapeutic efficacy of NIC could represent an additional option in the prevention of SRL-related thrombosis.

Procoagulatory state in inflammatory bowel diseases is promoted by impaired intestinal barrier function

Inflammatory and immune mediated disorders are risk factors for arterial and venous thromboembolism. Inflammatory bowel diseases (IBD) confer an even greater risk of thromboembolic events than other inflammatory conditions. It has been shown that IBD patients display defective intestinal barrier functions. Thus, pathogen-associated molecular patterns (PAMPs) coming from the intestinal bacterial burden might reach systemic circulation and activate innate immunity receptors on endothelial cells and platelets, promoting a procoagulative state. Aim of the study was to test this hypothesis, correlating the presence of circulating PAMPs with the activation of innate immune system and the activation of the coagulatory cascade in IBD patients. Specifically, we studied lipopolysaccharide (LPS), Toll-like receptor (TLR) 2, TLR4, and markers of activated coagulation (i.e., D-Dimer and prothrombin fragment F1+2) in the serum and plasma of IBD patients. We found that LPS levels are increased in IBD and correlate with TLR4 concentrations; although a mild correlation between LPS and CRP levels was detected, clinical disease activity does not appear to influence circulating LPS. Instead, serum LPS correlates with both D-Dimer and F1+2 measurements. Taken together, our data support the role of an impairment of intestinal barrier in triggering the activation of the coagulatory cascade in IBD.

Prehospital use of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with a reduced incidence of trauma-induced coagulopathy

OBJECTIVE

To determine whether prehospital nonsteroidal anti-inflammatory drug (NSAID) use may lead to a reduced incidence of trauma-induced coagulopathy (TIC) in severely injured patients.

BACKGROUND

TIC is present in up to a quarter of severely injured trauma patients and is linked to worse outcomes after injury. Evidence linking TIC to inflammation has emerged; however, the mechanism behind this association is still under investigation. NSAIDs are commonly used anti-inflammatory drugs, but their effects on TIC and outcomes after injury are largely unexplored.

METHODS

We performed a secondary analysis of the Inflammation and the Host Response to Injury Large Scale Collaborative Program (Glue Grant) data set. Prehospital medications and comorbidities were analyzed by logistic regression analysis for association with TIC as defined by laboratory (international normalized ratio >1.5) or clinical (transfusion >2 units of fresh frozen plasma or >1 pack of platelets in 6 hours) parameters.

RESULTS

Prehospital NSIAD use was independently associated with a 72% lower risk of TIC and was the only medication among 15 analyzed to retain significance in the model. Stepwise logistic regression also demonstrated that preadmission use of NSAIDs was independently associated with a 66% lower risk of clinically significant coagulopathy. These findings were independent of comorbid conditions linked to NSAID use.

CONCLUSIONS

NSAID use before admission for severe injury is associated with a reduced incidence of TIC. These findings provide further evidence to a potential leak between TIC and inflammation.

Trans-fatty acid promotes thrombus formation in mice by aggravating antithrombogenic endothelial functions via Toll-like receptors

SCOPE

Since excessive intake of trans-fatty acid (TFA) increases the risk of myocardial infarction, we investigated the effects of TFA on thrombus formation using animal and cell culture experiments.

METHODS AND RESULTS

C57BL/6 mice were fed a diet containing TFA or cis-fatty acid (5% each of total calories) or a chow diet for 4 weeks, and thrombus formation was induced in the carotid artery by He-Ne laser irradiation. The high-TFA diet significantly promoted thrombus formation in the carotid artery compared to the chow or cis-fatty acid diet. TFA activated the inflammatory signaling pathway in cultured endothelial cells and in mice; aortic gene expression levels of antithrombogenic molecules, including thrombomodulin and tissue factor pathway inhibitor, were decreased, and the expression levels of prothrombogenic molecules were increased in TFA-treated mice. TFA markedly upregulated the prothrombogenic molecules and downregulated the antithrombogenic molecules in endothelial cells. In addition, TFA induced phosphorylation of c-Jun N-terminal kinase, extracellular signal-regulated kinase, and nuclear factor-κB. The TFA-activated signal pathways and prothrombogenic phenotypic changes of endothelial cells were inhibited by genetic or pharmacological inactivation of Toll-like receptors 2 and 4.

CONCLUSION

TFA aggravates the antithrombogenic phenotypes of vascular endothelial cells via Toll-like receptors and promotes thrombus formation in mice.

Factor XII: a drug target for safe interference with thrombosis and inflammation

Data from experimental animal models revealed an essential role for factor XII (FXII) in thrombotic occlusive diseases. In contrast to other blood coagulation factors, deficiency in the protease is not associated with abnormal bleeding from injury sites (hemostasis) in patients or in animals. Cumulatively, these findings suggest that FXII could be targeted as a new method of anticoagulation that is devoid of bleeding risks. An FXIIa-neutralizing antibody, 3F7, has been developed that inhibited thrombosis in an extracorporeal membrane oxygenation (ECMO) system as efficiently as heparin. However, in sharp contrast to heparin, 3F7 treatment was not associated with an increase in therapy-associated hemorrhage. In this review, we summarize current knowledge of FXII physiology and pharmacology.

PAR-2, IL-4R, TGF-β and TNF-α in bronchoalveolar lavage distinguishes extrinsic allergic alveolitis from sarcoidosis

Sarcoidosis (SARC) and extrinsic allergic alveolitis (EAA) share certain markers, making a differential diagnosis difficult even with histopathological investigation. In lung tissue, proteinase-activated receptor-2 (PAR-2) is primarily investigated with regard to epithelial and inflammatory perspectives. Varying levels of certain chemokines can be a useful tool for distinguishing EAA and SARC. Thus, in the present study, differences in the levels of transforming growth factor (TGF)-β1, tumor necrosis factor (TNF)-α, interleukin-4 receptor (IL-4R) and PAR-2 in bronchoalveolar lavage fluid (BALF) were compared, using an ELISA method, between 14 patients with EAA and six patients with SARC. Statistically significant higher levels of IL-4R, PAR-2 and the PAR-2/TGF-β1 and PAR-2/TNF-α ratios were observed in EAA patients as compared with SARC patients. Furthermore, the ratios of TNF-α/total protein, TGF-β1/PAR-2 and TNF-α/PAR-2 were significantly lower in EAA patients than in SARC patients. The results indicated a higher detection of PAR-2 in EAA samples in association with TNF-α and TGF-β levels. As EAA and PAR-2 in parallel belong to the Th2-mediated pathway, the results significantly indicated an association between this receptor and etiology. In addition, the results indicated that SARC is predominantly a granulomatous inflammatory disease, thus, higher levels of TNF-α are observed. Therefore, the detection of PAR-2 and investigated chemokines in BALF may serve as a useful tool in the differential diagnosis between EAA and SARC.

Endocan is useful biomarker of survival and severity in sepsis

INTRODUCTION

Coagulation abnormalities which occur as a consequence of endothelial changes are recognized as diagnostic criteria for sepsis, but significance of these changes in the outcome prognosis and prediction of the course of sepsis is still not accurately defined.

MATERIALS AND METHODS

60 patients who fulfilled the criteria for diagnosis of sepsis were included in our study. Patients were categorized in two groups according to sepsis severity and organ failure and MODS development was assessed in the first 48 h from ICU admission. Prothrombin time (PT), activated partial thromboplastin time (aPTT) and endothelial cell specific molecule-1(endocan) levels, as well as procalcitonin (PCT) and C-reactive protein (CRP) were determined within the first 24h of the onset of the disease. Predictive APACHE II (Acute Physiology and Chronic Health Evaluation II) and SOFA (Sequential Organ Failure Assessment) scores were calculated on the day of ICU admission. Data were used to determine an association between day 1 biomarker levels, organ dysfunction score values and the development of organ failure, multiple organ dysfunction syndrome (MODS), and mortality during 28 days. These connections were determined by plotting of receiver operating characteristic (ROC) curves. Differences between groups were assessed by Mann-Whitney U test. Categorical variables were compared using chi-square test.

RESULTS

Concentration of endocan was significantly higher in the group of patients with sepsis induced organ failure, MODS development and in the group of non- survivors in contrast to group with less severe form of the disease, without multiorgan failure, and in contrast to group of survivors (p<0.05). Values of areas under the ROC curves showed that endocan levels had good discriminative power for more severe course of sepsis, MODS development and possible discriminative power for mortality prediction (AUC: 0.81, 0.67, 0.71 retrospectively), better than PCT for fatality (AUC:053) and better than APACHE II (AUC:0.55) and SOFA (AUC: 0.57) scores for organ failure.

CONCLUSIONS

Results of our study show that endocan can be used as strong and significant predictor of sepsis severity and outcome, perhaps even better than SOFA and APACHE II scores.

Inflammation and Coagulation as Mediators in the Relationships Between Religious Attendance and Functional Limitations in Older Adults

OBJECTIVE

The aim of this study was to examine inflammation and coagulation, which are positively linked to disability and inversely linked to increased religious attendance, as mediators in the cross-sectional relationships between religious attendance and functional status.

METHOD

Frequency of attendance and limitations in basic activities of daily living (ADLs), instrumental activities (IADLs), and mobility were assessed in 1,423 elders.

RESULTS

More frequent attendance was associated with fewer ADL, IADL, and mobility limitations, and with lower levels of inflammation and coagulation including interleukin-6, soluble vascular cell adhesion molecule, and D-dimer. Inflammation and coagulation partially mediated the associations between attendance and function. Eight percent of the effect of attendance on ADL (p = .014), 5% of the effect on IADL (p = .003), and 8% of the effect on mobility (p = .001) limitations were due to inflammation and coagulation.

DISCUSSION

Relationships between attendance and function may be due in part to lower levels of inflammation and coagulation among elders who attend services.

Thrombin drives tumorigenesis in colitis-associated colon cancer

The established association between inflammatory bowel disease and colorectal cancer underscores the importance of inflammation in colon cancer development. On the basis of evidence that hemostatic proteases are powerful modifiers of both inflammatory pathologies and tumor biology, gene-targeted mice carrying low levels of prothrombin were used to directly test the hypothesis that prothrombin contributes to tumor development in colitis-associated colon cancer (CAC). Remarkably, imposing a modest 50% reduction in circulating prothrombin in fII+/- mice, a level that carries no significant bleeding risk, dramatically decreased adenoma formation following an azoxymethane/dextran sodium sulfate challenge. Similar results were obtained with pharmacologic inhibition of prothrombin expression or inhibition of thrombin proteolytic activity. Detailed longitudinal analyses showed that the role of thrombin in tumor development in CAC was temporally associated with the antecedent inflammatory colitis. However, direct studies of the antecedent colitis showed that mice carrying half-normal prothrombin levels were comparable to control mice in mucosal damage, inflammatory cell infiltration, and associated local cytokine levels. These results suggest that thrombin supports early events coupled to inflammation-mediated tumorigenesis in CAC that are distinct from overall inflammation-induced tissue damage and inflammatory cell trafficking. That prothrombin is linked to early events in CAC was strongly inferred by the observation that prothrombin deficiency dramatically reduced the formation of very early, precancerous aberrant crypt foci. Given the importance of inflammation in the development of colon cancer, these studies suggest that therapeutic interventions at the level of hemostatic factors may be an effective means to prevent and/or impede colitis-associated colon cancer progression.

Proteomic analysis of differential protein expression in platelets of septic patients

Sepsis is one of the major health problems all over the world. Early diagnostic of sepsis is an attractive strategy to decrease the mortality of septic patients. However, an effective biomarker that fulfills all the necessary requirements for the accurate characterization of sepsis is still unavailable until now. In this study, the 2-DE technique followed by mass spectrometry and a database search was used for searching and identifying the differential expressed proteins in platelets between septic patients and paired healthy controls. Platelet 2-DE profiles of septic patients and paired healthy controls with high resolution and reproducibility were obtained. Differential platelet 2-DE profiles between septic patients and paired healthy controls were established. Differential protein spots between normal healthy volunteers and septic patients from platelet 2-DE profiles were identified by 2-DE followed with mass spectrometry and a database search. Five proteins with increased expression were identified between septic patients and healthy controls from platelet samples. These up-expressed proteins were EF-hand calcium-binding domain-containing protein 7, actin, interleukin-1β, glycoprotein IX, and glycoprotein IIB. Sepsis induces a complex regulation of platelet protein changes. Our study highlights the important role of these differential expressed proteins in sepsis, which deserve further research as potential candidates for therapeutic strategies. Furthermore, our research is beneficial for the future developments of sepsis diagnosis and therapy.

Platelet glycoprotein Ib-IX as a regulator of systemic inflammation

OBJECTIVE

The platelet glycoprotein Ib-IX (GP Ib-IX) receptor is a well-characterized adhesion receptor supporting hemostasis and thrombosis via interactions with von Willebrand factor. We examine the GP Ib-IX/von Willebrand factor axis in murine polymicrobial sepsis, as modeled by cecal ligation and puncture (CLP).

APPROACH AND RESULTS

Genetic absence of the GP Ib-IX ligand, von Willebrand factor, prolongs survival after CLP, but absence of the receptor, GP Ib-IX, does not. Because absence of either von Willebrand factor or GP Ib-IX significantly impairs hemostasis and thrombosis, we sought to define additional GP Ib-IX-dependent pathways impacting survival in the CLP model. We document that the absence of GP Ib-IX leads to reduced platelet-neutrophil and platelet-monocyte interactions. Twenty-four hours after CLP, absence of GP Ib-IX coincides with an alteration in cytokine levels, such as tumor necrosis factor-α secreted by monocytes, and increased macrophage-1 antigen expression by neutrophils.

CONCLUSIONS

In contrast to the well-characterized proinflammatory properties of platelets, we describe in the CLP model an anti-inflammatory property associated with platelet GP Ib-IX. Thus, a single platelet receptor displays a dual modulatory role in both the thrombotic and inflammatory pathways associated with polymicrobial sepsis. In sharing leucine-rich motifs with toll-like receptors, platelet GP Ib-IX can be considered a multifunctional participant in hemostasis, thrombosis, and the inflammatory cascade. The results highlight a dynamic role for platelets in systemic inflammation and add to the complex pathophysiologic events that occur during the dysregulated coagulation and inflammation associated with sepsis.

The multifunctional role of the pallilysin-associated Treponema pallidum protein, Tp0750, in promoting fibrinolysis and extracellular matrix component degradation

The mechanisms that facilitate dissemination of the highly invasive spirochaete, Treponema pallidum, are incompletely understood. Previous studies showed the treponemal metalloprotease pallilysin (Tp0751) possesses fibrin clot degradation capability, suggesting a role in treponemal dissemination. In the current study we report characterization of the functionally linked protein Tp0750. Structural modelling predicts Tp0750 contains a von Willebrand factor type A (vWFA) domain, a protein-protein interaction domain commonly observed in extracellular matrix (ECM)-binding proteins. We report Tp0750 is a serine protease that degrades the major clot components fibrinogen and fibronectin. We also demonstrate Tp0750 cleaves a matrix metalloprotease (MMP) peptide substrate that is targeted by several MMPs, enzymes central to ECM remodelling. Through proteomic analyses we show Tp0750 binds the endothelial fibrinolytic receptor, annexin A2, in a specific and dose-dependent manner. These results suggest Tp0750 constitutes a multifunctional protein that is able to (1) degrade infection-limiting clots by both inhibiting clot formation through degradation of host coagulation cascade proteins and promoting clot dissolution by complexing with host proteins involved in the fibrinolytic cascade and (2) facilitate ECM degradation via MMP-like proteolysis of host components. We propose that through these activities Tp0750 functions in concert with pallilysin to enable T. pallidum dissemination.

Mental disorders across the adult life course and future coronary heart disease: evidence for general susceptibility

BACKGROUND

Depression, anxiety, and psychotic disorders have been associated with an increased risk of coronary heart disease (CHD). It is unclear whether this association between mental health and CHD is present across a wider range of mental disorders.

METHODS AND RESULTS

Participants were 1 107 524 Swedish men conscripted at a mean age of 18.3 years. Mental disorders were assessed by psychiatric interview on conscription, and data on hospital admissions for mental disorder and CHD were obtained from national registers during 22.6 years of follow-up. An increased risk of incident CHD was evident across a range of mental disorders whether diagnosed at conscription or on later hospital admission. Age-adjusted hazard ratios (95% confidence intervals) according to diagnoses at conscription ranged from 1.30 (1.05, 1.62) (depressive disorders) to 1.90 (1.58, 2.38) (alcohol-related disorders). [corrected]. The equivalent figures according to diagnoses during hospital admission ranged from 1.49 (1.24-1.80) (schizophrenia) to 2.82 (2.53-3.13) (other substance use disorders). Associations were little changed by adjustment for parental socioeconomic status, or body mass index, diabetes mellitus, and blood pressure measured at conscription, but they were partially attenuated by the adjustment for smoking, alcohol intake, and intelligence measured at conscription, and for education and own socioeconomic position.

CONCLUSIONS

Increased risk of incident CHD is present across a range of mental disorders and is observable when the disorders are diagnosed at a young age.

Pathophysiologic mechanisms in septic shock

The systemic inflammatory response that occurs in the septic patient as a result of an infectious insult affects multiple organs and systems, causing numerous physiological derangements. Alterations in phagocytic, lymphocytic and endothelial cell function and immune regulation are evident, leading to heterogeneity in a host's response to a septic challenge. In addition, the normal hemostatic balance shifts toward a procoagulant state through alterations in tissue factor, antithrombin, protein C and the inhibition of fibinolysis, which can result in thrombus formation and paradoxical hemostatic failure. In an effort to diagnose sepsis and predict outcomes, biomarkers such as C-reactive protein, pro-calcitonin, pro- and anti-inflammatory cytokines have been investigated with varying results. Targeted therapies for sepsis, most notably Xigris (recombinant human activated protein C), have proven unsuccessful and treatment continues to remain reliant on source control, antibiotics and supportive interventions, specifically early goal-directed therapy. This brief review gives an overview of the immunopathologic and coagulopathic alterations that occur in sepsis, soluble inflammatory mediators as potential diagnostic and prognostic biomarkers, and the clinical management of the septic patient.

Influence of proinflammatory stimuli on the expression of vascular ribonuclease 1 in endothelial cells

Extracellular RNA (eRNA) released under injury or pathological conditions has been identified as a yet unrecognized vascular alarm signal to induce procoagulant, permeability-promoting, and proinflammatory activities. eRNA-induced functions were largely prevented by administration of RNase1 as a natural blood vessel-protective antagonist of eRNA. The aim of this study was to investigate the inflammatory regulation of endothelial cell RNase1, which is partly stored in Weibel-Palade bodies of these cells. Long-term treatment of human umbilical vein endothelial cells (HUVECs) with inflammatory agents like tumor necrosis factor α (TNF-α) or interleukin 1β (IL-1β), but not with eRNA, significantly decreased the release (34 ± 5%; 34 ± 7% of control) as well as the cellular expression (19.5 ± 5%; 33 ± 8% of control) of RNase1. Down-regulation of RNase1 by TNF-α stimulation or RNase1 siRNA knockdown increased the permeability of HUVEC monolayers, demonstrated by dearrangement of VE-cadherins at cell-cell borders. Mechanistically, cytokine-induced decrease of RNase1 expression did not involve the nuclear factor κ B (NFκB) signaling pathway but epigenic modifications. Since inhibition of histone deacetylases resulted in recovery of RNase1 expression and secretion after cytokine treatment, an acetylation-dependent process of RNase1 regulation is proposed. These results indicate that cytokine-mediated down-regulation of RNase1 in endothelial cells may aggravate eRNA-induced inflammatory activities and thereby disturbs the vascular homeostasis of the extracellular RNA/RNase system.

Impact of different types of resuscitation fluids on coagulation and continuous venovenous hemofiltration hemocompatibility in a porcine model

Intensive therapy demanding diseases (organ failure or sepsis) are assumed to be the etiology behind a decreased biocompatibility of extracorporeal systems for renal replacement therapy (RRT). There are also potential interactions between different components of the overall therapy. Volume substitutes are known to influence hemorheology and coagulation. To define a potential net effect of volume substitutes on the hemocompatibility of an RRT, we chose an animal model without interfering pathophysiologies. According to the problem of early filter failure and coagulation disorders in critically ill patients, we focused on the hypothesized interaction between RRT and different volume substitutes with respect to blood cell counts, coagulation parameters and required heparin dose. Forty-eight pigs were assigned to four groups of fluid therapy with either normal saline (NaCl), 6%HES130kD/0.4 (HES130), 6%HES200kD/0.5 (HES200) or 4%gelatin (GEL). Six pigs of each fluid group underwent continuous venovenous hemofiltration (CVVH), the remaining six served as the control group. Anticoagulation was performed with continuous heparin infusion. CVVH was run in a recirculation-mode for 4.5 h to force hemocompatibility reactions, thereafter in a standard-mode for 2 h. During the CVVH-treatment GEL reduced platelet counts and fibrinogen concentration and additionally lowered ATIII levels. Heparin requirements did not differ between different volume substitutes or CVVH and control groups. Severe pathophysiologies are not the only reason for a reduced hemocompatibility of CVVH treatment. Interaction of a particular volume substitute with CVVH should be considered when interpreting study results and evolving new strategies.

Lactobacillus rhamnosus CRL1505 beneficially modulates the immuno-coagulative response after pneumococcal infection in immunocompromised malnourished mice

This work evaluated the effect of orally or nasally administered Lactobacillus rhamnosus CRL1505 on the resistance of immunocompromised protein-malnourished mice to pneumococcal infection. In particular, we aimed to gain knowledge of the mechanism involved in the immunomodulatory effect of L. rhamnosus CRL1505 in malnourished hosts by evaluating its impact on the immuno-coagulative response. Malnutrition significantly increased lung tissue damage caused by Streptococcus pneumoniae infection. Lung damage was associated with a deregulated activation of coagulation and an altered inflammatory response. Pneumococcal colonization of lung and bacteremia were significantly reduced (p < 0.05) in malnourished mice receiving the CRL1505 strain. Moreover, mice repleted with supplemental L. rhamnosus CRL1505 showed the least alteration of the alveolar–capillary barrier and cell damage in lungs after the infectious challenge, especially when the CRL1505 strain was administered by nasal route. Besides, mice treated with L. rhamnosus CRL1505 showed an improved respiratory innate immune response and a lower activation of coagulation. The results of this work indicate that L. rhamnosus CRL1505 is able to beneficially modulate the inflammation–coagulation interaction after respiratory infections in malnourished hosts.