The inflammatory actions of coagulant and fibrinolytic proteases in disease

Synovial microenvironment in temporomandibular joint osteoarthritis: crosstalk with chondrocytes and potential therapeutic targets

Temporomandibular joint osteoarthritis (TMJOA) is considered to be a low-grade inflammatory disease involving multiple joint tissues. The crosstalk between synovium and cartilage plays an important role in TMJOA. Synovial cells are a group of heterogeneous cells and synovial microenvironment is mainly composed of synovial fibroblasts (SF) and synovial macrophages. In TMJOA, SF and synovial macrophages release a large number of inflammatory cytokines and extracellular vesicles and promote cartilage destruction. Cartilage wear particles stimulate SF proliferation and macrophages activation and exacerbate synovitis. In TMJOA, chondrocytes and synovial cells exhibit increased glycolytic activity and lactate secretion, leading to impaired chondrocyte matrix synthesis. Additionally, the synovium contains mesenchymal stem cells, which are the seed cells for cartilage repair in TMJOA. Co-culture of chondrocytes and synovial mesenchymal stem cells enhances the chondrogenic differentiation of stem cells. This review discusses the pathological changes of synovium in TMJOA, the means of crosstalk between synovium and cartilage, and their influence on each other. Based on the crosstalk between synovium and cartilage in TMJOA, we illustrate the treatment strategies for improving synovial microenvironment, including reducing cell adhesion, utilizing extracellular vesicles to deliver biomolecules, regulating cellular metabolism and targeting inflammatory cytokines.

Oxidative stress, defective proteostasis and immunometabolic complications in critically ill patients

Oxidative stress (OS) develops in critically ill patients as a metabolic consequence of the immunoinflammatory and degenerative processes of the tissues. These induce increased and/or dysregulated fluxes of reactive species enhancing their pro-oxidant activity and toxicity. At the same time, OS sustains its own inflammatory and immunometabolic pathogenesis, leading to a pervasive and vitious cycle of events that contribute to defective immunity, organ dysfunction and poor prognosis. Protein damage is a key player of these OS effects; it generates increased levels of protein oxidation products and misfolded proteins in both the cellular and extracellular environment, and contributes to forms DAMPs and other proteinaceous material to be removed by endocytosis and proteostasis processes of different cell types, as endothelial cells, tissue resident monocytes-macrophages and peripheral immune cells. An excess of OS and protein damage in critical illness can overwhelm such cellular processes ultimately interfering with systemic proteostasis, and consequently with innate immunity and cell death pathways of the tissues thus sustaining organ dysfunction mechanisms. Extracorporeal therapies based on biocompatible/bioactive membranes and new adsorption techniques may hold some potential in reducing the impact of OS on the defective proteostasis of patients with critical illness. These can help neutralizing reactive and toxic species, also removing solutes in a wide spectrum of molecular weights thus improving proteostasis and its immunometabolic corelates. Pharmacological therapy is also moving steps forward which could help to enhance the efficacy of extracorporeal treatments. This narrative review article explores the aspects behind the origin and pathogenic role of OS in intensive care and critically ill patients, with a focus on protein damage as a cause of impaired systemic proteostasis and immune dysfunction in critical illness.

Protracted fibrinolysis resistance following cardiac surgery with cardiopulmonary bypass: A prospective observational study of clinical associations and patient outcomes

BACKGROUND

Surgery on cardiopulmonary bypass (CPB) elicits a pleiomorphic systemic host response which, when severe, requires prolonged intensive care support. Given the substantial cross-talk between inflammation, coagulation, and fibrinolysis, the aim of this hypothesis-generating observational study was to document the kinetics of fibrinolysis recovery post-CPB using ClotPro® point-of-care viscoelastometry. Tissue plasminogen activator-induced clot lysis time (TPA LT, s) was correlated with surgical risk, disease severity, organ dysfunction and intensive care length of stay (ICU LOS).

RESULTS

In 52 patients following CPB, TPA LT measured on the first post-operative day (D1) correlated with surgical risk (EuroScore II, Spearman's rho .39, p < .01), time on CPB (rho = .35, p = .04), disease severity (APACHE II, rho = .52, p < .001) and organ dysfunction (SOFA, rho = .51, p < .001) scores, duration of invasive ventilation (rho = .46, p < .01), and renal function (eGFR, rho = -.65, p < .001). In a generalized linear regression model containing TPA LT, CPB run time and markers of organ function, only TPA LT was independently associated with the ICU LOS (odds ratio 1.03 [95% CI 1.01-1.05], p = .01). In a latent variables analysis, the association between TPA LT and the ICU LOS was not mediated by renal function and thus, by inference, variation in the clearance of intraoperative tranexamic acid.

CONCLUSIONS

This observational hypothesis-generating study in patients undergoing cardiac surgery with cardiopulmonary bypass demonstrated an association between the severity of fibrinolysis resistance, measured on the first post-operative day, and the need for extended postoperative ICU level support. Further examination of the role of persistent fibrinolysis resistance on the clinical outcomes in this patient cohort is warranted through large-scale, well-designed clinical studies.

Advances in modeling techniques for the production and purification of biomolecules: A comprehensive review

In response to the growing demand for therapeutic biomolecules, there is a need for continuous and cost-effective bio-separation techniques to enhance extraction yield and efficiency. Aqueous biphasic extractive fermentation has emerged as an integrated downstream processing technique, offering selective partitioning, high productivity, and preservation of biomolecule integrity. However, the dynamic nature of this technique requires a comprehensive understanding of the underlying separation mechanisms. Unfortunately, the analysis of parameters influencing this dynamic behavior can be challenging due to limited resources and time. To address this, mathematical modeling approaches can be employed to minimize the tedious trial-and-error experimentation process. This review article presents mathematical modeling approaches for both upstream and downstream processing techniques, focusing on the production of biomolecules which can be used in pharmaceutical industries in a cost-effective manner. By leveraging mathematical models, researchers can optimize the production and purification processes, leading to improved efficiency and processing cost reduction in biomolecule production.

Interorgan communication with the liver: novel mechanisms and therapeutic targets

The liver is a multifunctional organ that plays crucial roles in numerous physiological processes, such as production of bile and proteins for blood plasma, regulation of blood levels of amino acids, processing of hemoglobin, clearance of metabolic waste, maintenance of glucose, etc. Therefore, the liver is essential for the homeostasis of organisms. With the development of research on the liver, there is growing concern about its effect on immune cells of innate and adaptive immunity. For example, the liver regulates the proliferation, differentiation, and effector functions of immune cells through various secreted proteins (also known as "hepatokines"). As a result, the liver is identified as an important regulator of the immune system. Furthermore, many diseases resulting from immune disorders are thought to be related to the dysfunction of the liver, including systemic lupus erythematosus, multiple sclerosis, and heart failure. Thus, the liver plays a role in remote immune regulation and is intricately linked with systemic immunity. This review provides a comprehensive overview of the liver remote regulation of the body's innate and adaptive immunity regarding to main areas: immune-related molecules secreted by the liver and the liver-resident cells. Additionally, we assessed the influence of the liver on various facets of systemic immune-related diseases, offering insights into the clinical application of target therapies for liver immune regulation, as well as future developmental trends.

Association of Fibrinolytic Potential and Risk of Mortality in Cancer Patients

Cancer is a leading cause of death, and the fibrinolytic system shows cooperative effects that facilitate the growth of tumors and the appearance of metastases. This prospective study aimed to evaluate the fibrinolytic potential in cancer patients and its association with mortality outcomes using the fluorometric method of simultaneous thrombin and plasmin generation. The study included 323 cancer patients and 148 healthy individuals. During the 12-month follow-up, 68 patients died. Compared to the control group, cancer patients showed alterations in thrombin production consistent with a hypercoagulability profile, and an increase in plasmin generation. Mortality risk was associated with two parameters of thrombin in both univariate and multivariable analysis: maximum amplitude (Wald 11.78, p < 0.001) and area under the curve (Wald 8.0, p < 0.005), while such associations were not observed for plasmin. In conclusion, this was the first study able to demonstrate the simultaneous evaluation of thrombin and plasmin generation in newly diagnosed untreated cancer patients. Patients with cancer have been observed to exhibit a hypercoagulable profile. During the study, two parameters linked to thrombin generation, MA and AUC, were identified and found to have a potential association with mortality risk. However, no associations were found with parameters related to plasmin generation.

Association Between Tranexamic Acid Use and Heterotopic Ossification Prevalence After Elbow Trauma Surgery: A Propensity-Score-Matched Cohort Study

BACKGROUND

Heterotopic ossification (HO) is a common complication of elbow trauma that can affect limb mobility. Inflammation is an initiating factor for HO formation. Tranexamic acid (TXA) can reduce the inflammatory response after orthopaedic surgery. However, evidence regarding the effectiveness of TXA use for HO prevention after elbow trauma surgery is lacking.

METHODS

This retrospective observational propensity-score-matched (PSM) cohort study was conducted from July 1, 2019, to June 30, 2021, at the National Orthopedics Clinical Medical Center, Shanghai, People's Republic of China. A total of 640 patients who underwent surgery following elbow trauma were evaluated. The present study excluded patients with an age of <18 years; those with a history of elbow fracture; those with a central nervous system injury, spinal cord injury, burn injury, or destructive injury; and those who had been lost to follow-up. After 1:1 matching on the basis of sex, age, dominant arm, injury type, open injury, comminuted fracture, ipsilateral trauma, time from injury to surgery, and nonsteroidal anti-inflammatory drug use, the TXA group and the no-TXA group comprised 241 patients each.

RESULTS

In the PSM population, the prevalence of HO was 8.71% in the TXA group and 16.18% in the no-TXA group (with rates of 2.07% and 5.80% for clinically important HO, respectively). Logistic regression analyses showed that TXA use was associated with a lower rate of HO (odds ratio [OR], 0.49; 95% CI, 0.28 to 0.86; p = 0.014) than no TXA use, as well as with a lower rate of clinically important HO (OR, 0.34; 95% CI, 0.11 to 0.91; p = 0.044). None of the baseline covariates significantly affected the relationship between TXA use and HO rate (p > 0.05 for all). Sensitivity analyses supported these findings.

CONCLUSIONS

TXA prophylaxis may be an appropriate method for the prevention of HO following elbow trauma.

LEVEL OF EVIDENCE

Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Towards a Unified Approach in Autoimmune Fibrotic Signalling Pathways

Autoimmunity is a chronic process resulting in inflammation, tissue damage, and subsequent tissue remodelling and organ fibrosis. In contrast to acute inflammatory reactions, pathogenic fibrosis typically results from the chronic inflammatory reactions characterizing autoimmune diseases. Despite having obvious aetiological and clinical outcome distinctions, most chronic autoimmune fibrotic disorders have in common a persistent and sustained production of growth factors, proteolytic enzymes, angiogenic factors, and fibrogenic cytokines, which together stimulate the deposition of connective tissue elements or epithelial to mesenchymal transformation (EMT) that progressively remodels and destroys normal tissue architecture leading to organ failure. Despite its enormous impact on human health, there are currently no approved treatments that directly target the molecular mechanisms of fibrosis. The primary goal of this review is to discuss the most recent identified mechanisms of chronic autoimmune diseases characterized by a fibrotic evolution with the aim to identify possible common and unique mechanisms of fibrogenesis that might be exploited in the development of effective antifibrotic therapies.

Molecular Basic of Pharmacotherapy of Cytokine Imbalance as a Component of Intervertebral Disc Degeneration Treatment

Intervertebral disc degeneration (IDD) and associated conditions are an important problem in modern medicine. The onset of IDD may be in childhood and adolescence in patients with a genetic predisposition. With age, IDD progresses, leading to spondylosis, spondylarthrosis, herniated disc, spinal canal stenosis. One of the leading mechanisms in the development of IDD and chronic back pain is an imbalance between pro-inflammatory and anti-inflammatory cytokines. However, classical therapeutic strategies for correcting cytokine imbalance in IDD do not give the expected response in more than half of the cases. The purpose of this review is to update knowledge about new and promising therapeutic strategies based on the correction of the molecular mechanisms of cytokine imbalance in patients with IDD. This review demonstrates that knowledge of the molecular mechanisms of the imbalance between pro-inflammatory and anti-inflammatory cytokines may be a new key to finding more effective drugs for the treatment of IDD in the setting of acute and chronic inflammation.

Fibrinogen Is Associated with Prognosis of Critically Ill Patients with Sepsis: A Study Based on Cox Regression and Propensity Score Matching

Introduction

Sepsis is a common syndrome in critically ill patients. Fibrinogen was reported to be associated with the prognosis of sepsis patients.

Materials and Methods

Data was acquired from Multiparameter Intelligent Monitoring in Intensive Care Database IV (MIMIC-IV) version 1.0. Cox proportional hazards regression was utilized to estimate the relationship between fibrinogen and inhospital mortality. The cumulative incidence of mortality by fibrinogen level was estimated through the Kaplan-Meier curve. Restricted cubic spline (RCS) was used to assess nonlinear relationship. Subgroup analysis was also conducted to evaluate the robustness of the association between fibrinogen and inhospital mortality. Propensity score matching (PSM) was applied to adjust for confounding factors.

Results

A total of 3365 patients, including 2031 survivors and 1334 nonsurvivors, were enrolled in our study. The survivors had a significantly elevated levels of fibrinogen compared with the deceased. The elevated level of fibrinogen was significantly associated with a decrease in mortality in multivariate Cox regression before and after PSM (HR 0.66, P < 0.001 and HR 0.73, P < 0.001, respectively). RCS showed a nearly linear relationship. Subgroup analysis demonstrated the robustness of the association in most subpopulations. However, the association between decreased levels of fibrinogen and increased inhospital mortality was denied after PSM.

Conclusion

The elevated level of fibrinogen hints at better overall survival in critically ill patients with sepsis. Decreased levels of fibrinogen may be of little value in identifying patients with a high risk of death.

Empiric Anticoagulation Therapy in Hospitalized COVID-19 Patients: An Evaluation of Bleeding Risk Scores Performances in Predicting Bleeding Events

Currently, there is no standardized consensus on anticoagulation (AC) among patients with coronavirus disease (COVID-19), which has an overwhelming bleeding risk. We aimed to compare the patterns of AC in COVID-19 patients and compare two validated risk scores in predicting bleeding events. A retrospective review of medical records was conducted for COVID-19 patients who received empiric anticoagulation therapy. The primary outcomes included bleeding events, survival, and mechanical ventilation needs. We applied the HAS-BLED and ORBIT bleeding risk scores to assess the predictive accuracy, using c-statistics and the receiver operating curve (ROC) method. Of the included patients (n = 921), with a mean age of 58.1 ± 13.2, 51.6% received therapeutic AC and 48.4% received a prophylactic AC dose. Significantly higher values of d-dimer and C-reactive protein (CRP) among the therapeutic AC users (p < 0.001) were noted with a significantly prolonged duration of hospital stay and mechanical ventilation (p < 0.001 and p = 0.011, respectively). The mean value of the HAS-BLED and ORBIT scores were 2.53 ± 0.93 and 2.26 ± 1.29, respectively. The difference between the two tested scores for major bleeding and clinically relevant non-major bleeding was significant (p = 0.026 and 0.036, respectively) with modest bleeding predictive performances. The therapeutic AC was associated with an increased risk of bleeding. HAS-BLED showed greater accuracy than ORBIT in bleeding risk predictability.

Mechanisms of neuroinflammation in hydrocephalus after intraventricular hemorrhage: a review

Intraventricular hemorrhage (IVH) is a significant cause of morbidity and mortality in both neonatal and adult populations. IVH not only causes immediate damage to surrounding structures by way of mass effect and elevated intracranial pressure; the subsequent inflammation causes additional brain injury and edema. Of those neonates who experience severe IVH, 25-30% will go on to develop post-hemorrhagic hydrocephalus (PHH). PHH places neonates and adults at risk for white matter injury, seizures, and death. Unfortunately, the molecular determinants of PHH are not well understood. Within the past decade an emphasis has been placed on neuroinflammation in IVH and PHH. More information has come to light regarding inflammation-induced fibrosis and cerebrospinal fluid hypersecretion in response to IVH. The aim of this review is to discuss the role of neuroinflammation involving clot-derived neuroinflammatory factors including hemoglobin/iron, peroxiredoxin-2 and thrombin, as well as macrophages/microglia, cytokines and complement in the development of PHH. Understanding the mechanisms of neuroinflammation after IVH may highlight potential novel therapeutic targets for PHH.

α2-Antiplasmin as a Potential Therapeutic Target for Systemic Sclerosis

Systemic sclerosis is a connective tissue disease of unknown origin that is characterized by immune system abnormalities, vascular damage, and extensive fibrosis of the skin and visceral organs. α2-antiplasmin is known to be the main plasmin inhibitor and has various functions such as cell differentiation and cytokine production, as well as the regulation of the maintenance of the immune system, endothelial homeostasis, and extracellular matrix metabolism. The expression of α2-antiplasmin is elevated in dermal fibroblasts from systemic sclerosis patients, and the blockade of α2-antiplasmin suppresses fibrosis progression and vascular dysfunction in systemic sclerosis model mice. α2-antiplasmin may have promise as a potential therapeutic target for systemic sclerosis. This review considers the role of α2-antiplasmin in the progression of systemic sclerosis.

Pharmacological inhibition of TLR4-NF-κB signaling by TAK-242 attenuates hydrocephalus after intraventricular hemorrhage

Compelling evidence has confirmed that inflammatory pathways involving TLR4-regulated cytokines and immune cells are vitallyimportant for the pathogenesis of posthemorrhagic hydrocephalus (PHH), hinting that pharmacological prevention of PHH is feasible. TAK-242, as a toll-like receptor 4 (TLR4) inhibitor, downregulates TLR4-induced inflammatory responses and becomes a potent and noveltherapeuticdrugcandidatefor PHH. In the present study, we investigate whether TAK-242 protects against hydrocephalus and improves the prognosis of intraventricular hemorrhage (IVH). We also explore the possible role of TAK-242 for the regulation of TLR4-NF-κB signaling pathway. A model of PHH was conducted in 6-week-old Male Sprague-Dawley (SD) rats. The rats were divided into four main groups, including the sham, IVH + vehicle, IVH + TAK-242 and IVH groups. Magnetic resonance imaging (MRI) was applied to measure the lateral ventricle volume. Western blot (WB) and immunofluorescence (IF) were applied to detect the expression of TLR4, NF-κB, fibronectin and laminin. A combined scoring system and Morris water maze were employed to evaluate neurological functions after IVH. We found that IVH induced heightened activation of TLR4-NF-κB signaling pathway. We observed the increased lateral ventricular volume, elevation of NF-κB in choroidplexus, as well as fibronectin and laminin in the subarachnoid space (SAS) and ventricular wall after IVH. Obviously, TAK-242 treatment effectively inhibited the up-regulation of NF-κB, fibronectin, laminin and significantly alleviated ventriculomegaly after IVH. Importantly, TAK-242 improved neurocognitive deficits after PHH. In conclusion, TAK-242 attenuated IVH-induced hydrocephalus and improved the prognosis of PHH. The underlying mechanism involved the TAK-242-mediated downregulation of TLR4-NF-κB signaling pathway.

The interplay of fibroblasts, the extracellular matrix, and inflammation in scar formation

Various forms of fibrosis, comprising tissue thickening and scarring, are involved in 40% of deaths across the world. Since the discovery of scarless functional healing in fetuses prior to a certain stage of development, scientists have attempted to replicate scarless wound healing in adults with little success. While the extracellular matrix (ECM), fibroblasts, and inflammatory mediators have been historically investigated as separate branches of biology, it has become increasingly necessary to consider them as parts of a complex and tightly regulated system that becomes dysregulated in fibrosis. With this new paradigm, revisiting fetal scarless wound healing provides a unique opportunity to better understand how this highly regulated system operates mechanistically. In the following review, we navigate the four stages of wound healing (hemostasis, inflammation, repair, and remodeling) against the backdrop of adult versus fetal wound healing, while also exploring the relationships between the ECM, effector cells, and signaling molecules. We conclude by singling out recent findings that offer promising leads to alter the dynamics between the ECM, fibroblasts, and inflammation to promote scarless healing. One factor that promises to be significant is fibroblast heterogeneity and how certain fibroblast subpopulations might be predisposed to scarless healing. Altogether, reconsidering fetal wound healing by examining the interplay of the various factors contributing to fibrosis provides new research directions that will hopefully help us better understand and address fibroproliferative diseases, such as idiopathic pulmonary fibrosis, liver cirrhosis, systemic sclerosis, progressive kidney disease, and cardiovascular fibrosis.

Old and New Players of Inflammation and Their Relationship With Cancer Development

Pathogens or genotoxic agents continuously affect the human body. Acute inflammatory reaction induced by a non-sterile or sterile environment is triggered for the efficient elimination of insults that caused the damage. According to the insult, pathogen-associated molecular patterns, damage-associated molecular patterns, and homeostasis-altering molecular processes are released to facilitate the arrival of tissue resident and circulating cells to the injured zone to promote harmful agent elimination and tissue regeneration. However, when inflammation is maintained, a chronic phenomenon is induced, in which phagocytic cells release toxic molecules damaging the harmful agent and the surrounding healthy tissues, thereby inducing DNA lesions. In this regard, chronic inflammation has been recognized as a risk factor of cancer development by increasing the genomic instability of transformed cells and by creating an environment containing proliferation signals. Based on the cancer immunoediting concept, a rigorous and regulated inflammation process triggers participation of innate and adaptive immune responses for efficient elimination of transformed cells. When immune response does not eliminate all transformed cells, an equilibrium phase is induced. Therefore, excessive inflammation amplifies local damage caused by the continuous arrival of inflammatory/immune cells. To regulate the overstimulation of inflammatory/immune cells, a network of mechanisms that inhibit or block the cell overactivity must be activated. Transformed cells may take advantage of this process to proliferate and gradually grow until they become preponderant over the immune cells, preserving, increasing, or creating a microenvironment to evade the host immune response. In this microenvironment, tumor cells resist the attack of the effector immune cells or instruct them to sustain tumor growth and development until its clinical consequences. With tumor development, evolving, complex, and overlapping microenvironments are arising. Therefore, a deeper knowledge of cytokine, immune, and tumor cell interactions and their role in the intricated process will impact the combination of current or forthcoming therapies.

Pre-Operative Plasma Extracellular Vesicle Proteins are Associated with a High Risk of Long Term Secondary Major Cardiovascular Events in Patients Undergoing Carotid Endarterectomy

OBJECTIVE

Patients undergoing carotid endarterectomy (CEA) maintain a substantial residual risk of major cardiovascular events (MACE). Improved risk stratification is warranted to select high risk patients qualifying for secondary add on therapy. Plasma extracellular vesicles (EVs) are involved in atherothrombotic processes and their content has been related to the presence and recurrence of cardiovascular events. The association between pre-operative levels of five cardiovascular disease related proteins in plasma EVs and the post-operative risk of MACE was assessed.

METHODS

In 864 patients undergoing CEA from 2002 to 2016 included in the Athero-Express biobank, three plasma EV subfractions (low density lipoprotein [LDL], high density lipoprotein [HDL], and tiny extracellular vesicles [TEX]) were isolated from pre-operative blood samples. Using an electrochemiluminescence immunoassay, five proteins were quantified in each EV subfraction: cystatin C, serpin C1, serpin G1, serpin F2, and CD14. The association between EV protein levels and the three year post-operative risk of MACE (any stroke, myocardial infarction, or cardiovascular death) was evaluated using multivariable Cox proportional hazard regression analyses.

RESULTS

During a median follow up of three years (interquartile range 2.2 - 3.0), 137 (16%) patients developed MACE. In the HDL-EV subfraction, increased levels of CD14, cystatin C, serpin F2, and serpin C1 were associated with an increased risk of MACE (adjusted hazard ratios per one standard deviation increase of 1.30, 95% confidence interval [CI] 1.15-1.48; 1.22, 95% CI 1.06-1.42; 1.36, 95% CI 1.16-1.61; and 1.29, 95% CI 1.10-1.51; respectively), independently of cardiovascular risk factors. No significant associations were found for serpin G1. CD14 improved the predictive value of the clinical model encompassing cardiovascular risk factors (net re-classification index = 0.16, 95% CI 0.08-0.21).

CONCLUSION

EV derived pre-operative plasma levels of cystatin C, serpin C1, CD14, and serpin F2 were independently associated with an increased long term risk of MACE after CEA and are thus markers for residual cardiovascular risk. EV derived CD14 levels could improve the identification of high risk patients who may benefit from secondary preventive add on therapy in order to reduce future risk of MACE.

Ageing mechanisms that contribute to tissue remodeling in lung disease

Age is a major risk factor for chronic respiratory diseases such as idiopathic pulmonary fibrosis (IPF), chronic obstructive pulmonary disease (COPD) and certain phenotypes of asthma. The recent COVID-19 pandemic also highlights the increased susceptibility of the elderly to acute respiratory distress syndrome (ARDS), a diffuse inflammatory lung injury with often long-term effects (ie parenchymal fibrosis). Collectively, these lung conditions are characterized by a pathogenic reparative process that, rather than restoring organ function, contributes to structural and functional tissue decline. In the ageing lung, the homeostatic control of wound healing following challenge or injury has an increased likelihood of being perturbed, increasing susceptibility to disease. This loss of fidelity is a consequence of a diverse range of underlying ageing mechanisms including senescence, mitochondrial dysfunction, proteostatic stress and diminished autophagy that occur within the lung, as well as in other tissues, organs and systems of the body. These ageing pathways are highly interconnected, involving localized and systemic increases in inflammatory mediators and damage associated molecular patterns (DAMPs); along with corresponding changes in immune cell function, metabolism and composition of the pulmonary and gut microbiomes. Here we comprehensively review the roles of ageing mechanisms in the tissue remodeling of lung disease.

Involvement of Inflammation in Venous Thromboembolic Disease: An Update in the Age of COVID-19

The inflammatory process is strongly involved in the pathophysiology of venous thromboembolism (VTE) and has a significant role in disease prediction. Inflammation most probably represents a common denominator through which classical and nonclassical risk factors stimulate thrombotic process. Inflammation of the venous wall promotes the release of tissue factor, inhibits the release of anticoagulant factors, and hampers endogenous fibrinolysis. Systemic inflammatory response also inhibits restoration of blood flow in the occluded vessel. Recent studies indicate that increased inflammatory response ("cytokine storm") is related to prothrombotic state and thromboembolic events in patients with coronavirus disease 2019 (COVID-19). The growing evidence of involvement of inflammation in the pathogenesis of VTE indicates the importance of anti-inflammatory treatment and prevention of VTE. While aspirin was shown to be effective in prevention of recurrent venous thrombosis after treatment with anticoagulant drugs, some other anti-inflammatory drugs like nonsteroidal anti-inflammatory agents may have prothrombotic effect, thus potentially increasing the risk of VTE. Recently, new specific anti-inflammatory drug inhibitors of inflammatory markers that have been shown to be involved in the pathogenesis of VTE are being searched. As thrombogenesis is based on activation of coagulation provoked by inflammation, then prevention and treatment of VTE should include both anticoagulant and anti-inflammatory agents. Combined treatment is related to increased risk of bleeding complications, therefore subtherapeutic doses of both drugs should be used to improve the efficacy of management of VTE without increasing the risk of bleeding.

Transthyretin: From Structural Stability to Osteoarticular and Cardiovascular Diseases

Transthyretin (TTR) is a tetrameric protein transporting hormones in the plasma and brain, which has many other activities that have not been fully acknowledged. TTR is a positive indicator of nutrition status and is negatively correlated with inflammation. TTR is a neuroprotective and oxidative-stress-suppressing factor. The TTR structure is destabilized by mutations, oxidative modifications, aging, proteolysis, and metal cations, including Ca2+. Destabilized TTR molecules form amyloid deposits, resulting in senile and familial amyloidopathies. This review links structural stability of TTR with the environmental factors, particularly oxidative stress and Ca2+, and the processes involved in the pathogenesis of TTR-related diseases. The roles of TTR in biomineralization, calcification, and osteoarticular and cardiovascular diseases are broadly discussed. The association of TTR-related diseases and vascular and ligament tissue calcification with TTR levels and TTR structure is presented. It is indicated that unaggregated TTR and TTR amyloid are bound by vicious cycles, and that TTR may have an as yet undetermined role(s) at the crossroads of calcification, blood coagulation, and immune response.

Annexin A2 in Fibrinolysis, Inflammation and Fibrosis

As a cell surface tissue plasminogen activator (tPA)-plasminogen receptor, the annexin A2 (A2) complex facilitates plasmin generation on the endothelial cell surface, and is an established regulator of hemostasis. Whereas A2 is overexpressed in hemorrhagic disease such as acute promyelocytic leukemia, its underexpression or impairment may result in thrombosis, as in antiphospholipid syndrome, venous thromboembolism, or atherosclerosis. Within immune response cells, A2 orchestrates membrane repair, vesicle fusion, and cytoskeletal organization, thus playing a critical role in inflammatory response and tissue injury. Dysregulation of A2 is evident in multiple human disorders, and may contribute to the pathogenesis of various inflammatory disorders. The fibrinolytic system, moreover, is central to wound healing through its ability to remodel the provisional matrix and promote angiogenesis. A2 dysfunction may also promote tissue fibrogenesis and end-organ fibrosis.

Investigating the Multi-Faceted Nature of Radiation-Induced Coagulopathies in a Göttingen Minipig Model of Hematopoietic Acute Radiation Syndrome

Coagulopathies are well documented after acute radiation exposure at hematopoietic doses, and radiation-induced bleeding is notably one of the two main causes of mortality in the hematopoietic acute radiation syndrome. Despite this, understanding of the mechanisms by which radiation alters hemostasis and induces bleeding is still lacking. Here, male Göttingen minipigs received hematopoietic doses of 60Co gamma irradiation (total body) and coagulopathies were characterized by assessing bleeding, blood cytopenia, fibrin deposition, changes in hemostatic properties, coagulant/anticoagulant enzyme levels, and markers of inflammation, endothelial dysfunction, and barrier integrity to understand if a relationship exists between bleeding, hemostatic defects, bone marrow aplasia, inflammation, endothelial dysfunction and loss of barrier integrity. Acute radiation exposure induced coagulopathies in the Göttingen minipig model of hematopoietic acute radiation syndrome; instances of bleeding were not dependent upon thrombocytopenia. Neutropenia, alterations in hemostatic parameters and damage to the glycocalyx occurred in all animals irrespective of occurrence of bleeding. Radiation-induced bleeding was concurrent with simultaneous thrombocytopenia, anemia, neutropenia, inflammation, increased heart rate, decreased nitric oxide bioavailability and endothelial dysfunction; bleeding was not observed with the sole occurrence of a single aforementioned parameter in the absence of the others. Alteration of barrier function or clotting proteins was not observed in all cases of bleeding. Additionally, fibrin deposition was observed in the heart and lungs of decedent animals but no evidence of DIC was noted, suggesting a unique pathophysiology of radiation-induced coagulopathies. These findings suggest radiation-induced coagulopathies are the result of simultaneous damage to several key organs and biological functions, including the immune system, the inflammatory response, the bone marrow and the cardiovasculature.

Inflammatory mediators in various molecular pathways involved in the development of pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a type of interstitial lung disease (ILD) that is marked by scarring of lung tissue, ultimately leading to respiratory failure. The survival rate of IPF is disappointing and to date demonstrates a clinical quandary. The exact etiology of the disease remains under discussion. According to the recent hypothesis, inflammatory mediators cause severe damage to the alveolar epithelium leading to the impairment of the alveolar structure. The role of inflammation in the development of the IPF has been controversial for years. There are two schools of thought regarding the role of inflammation. One group of researchers claims that cell death and fibroblast dysfunction are the primary causes and inflammation is just a secondary cause of IPF. The other group claims inflammation to be the primary cause. Studies using human subjects have also reported inflammation as a critical element in IPF. Inflammatory cytokinesserve amajor rolein commencing theinflammatoryresponse in the lungs. Several cytokines are reported to be involved in different molecular mechanisms underlying IPF, someof which alsocontribute additionally by acting as growth factors. The present review addressed to explore the contribution of various inflammatory cytokines, growth factors, and various other inflammatory molecules activating the major molecular pathways involved during the development of IPF.

COVID-19 Related Acute Hemorrhagic Necrotizing Encephalitis: A Report of Two Cases and Literature Review

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus, has proven neurotropism and causes a multitude of neurologic manifestations. Acute hemorrhagic necrotizing encephalitis (AHNE), though rare, can be seen in patients with severe infection and is associated with devastating neurologic outcomes. The true prevalence of this syndrome is unknown due to underrecognition, difficulty in timely acquisition of neuroimaging, and high mortality in this subset of patients escaping detection. It is a distinct clinicoradiological syndrome, with patients suffering from rapidly worsening encephalopathy and coma within the first two weeks of severe illness and hemorrhagic necrotizing parenchymal changes on neuroimaging. The pathophysiology of this syndrome is unclear but hypothesized to occur due to cytokine storm, blood-brain-barrier dysfunction, and direct viral-mediated endotheliopathy. Diagnosis requires a high index of suspicion in patients who have unexplained persistent severe encephalopathy associated with COVID-19 infection. Most patients have elevated systemic inflammatory markers and severe lung disease with hypoxic respiratory failure requiring mechanical ventilation. MRI is the imaging modality of choice, with a distinct neuroimaging pattern. CSF (cerebrospinal fluid) studies have a low yield for viral particle detection with currently available testing. While long-term outcomes are unclear, early immunomodulatory treatment with intravenous immunoglobulin, plasma exchange, and steroids may portend a favorable outcome. We discuss two cases of COVID-19 related AHNE and also include a pertinent literature search of similar cases in PubMed to consolidate the AHNE clinical syndrome, neuroimaging characteristics, management strategies, and reported short-term prognosis.

Salvianolic acid B inhalation solution enhances antifibrotic and anticoagulant effects in a rat model of pulmonary fibrosis

The purpose of this study was to investigate the antifibrotic effect and anticoagulant ability of salvianolic acid B (SAB) inhalation solution on bleomycin (BLM)-induced idiopathic pulmonary fibrosis (IPF) in rats. We investigated how the osmotic pressure and concentration of SAB in an aerosol exerted effects. We also determined the aerodynamic particle size distribution and the uniformity of the delivery dose; these parameters were found to be suitable for inhalation. Compared with BLM group, the levels of hydroxyproline (HYP), collagen-1 (Col-1), tissue factor (TF) / coagulation factor VII (TF-VIIa), activated coagulation factor X (FXa), thrombin-antithrombin complex (TAT), fibrinogen degradation product (FDP) and plasminogen activator inhibitor-1 (PAI-1) decreased in SAB group. The increased expression of coagulation factor Ⅱ (FⅡ), coagulation factor X (FX), tissue type plasminogen activator (t-PA) and urokinase type plasminogen activator (u-PA) proved that SAB has obvious antifibrotic and anticoagulant effects. Western blotting and immunofluorescence further showed that compared with the BLM group, the SAB group of rats exhibited significant reductions in the expression levels of protease-activated receptors-1 (PAR-1) and phospho-protein kinase C (p-PKC) and increased expression levels of protein kinase C (PKC) in lung tissue. Furthermore, SAB reduced the infiltration of lymphocytes and neutrophils, protected the basic structure of the lung from destruction, inhibited the proliferation of fibrous tissue. Collectively, our data revealed that SAB may exert its antifibrotic and anticoagulant effects by preventing the expression of PAR-1 and phosphorylation of PKC.

Organ Fibrosis and Autoimmunity: The Role of Inflammation in TGFβ-Dependent EMT

Recent advances in our understanding of the molecular pathways that control the link of inflammation with organ fibrosis and autoimmune diseases point to the epithelial to mesenchymal transition (EMT) as the common association in the progression of these diseases characterized by an intense inflammatory response. EMT, a process in which epithelial cells are gradually transformed to mesenchymal cells, is a major contributor to the pathogenesis of fibrosis. Importantly, the chronic inflammatory microenvironment has emerged as a decisive factor in the induction of pathological EMT. Transforming growth factor-β (TGF-β), a multifunctional cytokine, plays a crucial role in the induction of fibrosis, often associated with chronic phases of inflammatory diseases, contributing to marked fibrotic changes that severely impair normal tissue architecture and function. The understanding of molecular mechanisms underlying EMT-dependent fibrosis has both a basic and a translational relevance, since it may be useful to design therapies aimed at counteracting organ deterioration and failure. To this end, we reviewed the recent literature to better elucidate the molecular response to inflammatory/fibrogenic signals in autoimmune diseases in order to further the specific regulation of EMT-dependent fibrosis in more targeted therapies.

Thrombocytopenia: is it a prognostic factor for development of post-hemorrhagic hydrocephalus in neonates?

PURPOSE

Post-hemorrhagic hydrocephalus (PHH) is a rare but serious complication among premature babies in the neonatal intensive care unit. The causes of PHH are still not entirely understood, and its prevention and treatment are controversial. We tried to analyze the risk factors for such complication in our cohort.

METHODS

We reviewed our neonatology data bank and included all preterms below 28 weeks who were born in the period between 1999 and 2014 and suffered from an intraventricular hemorrhage (IVH). We reviewed gestational age, gender, birth weight, type of birth, IVH degree, comorbidities, therapy, complications, time to event, protein content of cerebrospinal fluid, and clinical follow-up.

RESULTS

We identified 180 patients, divided into two subgroups, "B1" with 37 cases (IVH + PHH) and "B2" with 143 cases (IVH - PHH). In group B1, the presence of IVH grades I, II, III, or IV was in 11%, 19%, and 70% respectively. Nineteen patients were treated with a ventricular access device (VAD) or external ventricular drain (EVD). A total of 20 shunts were implanted, with 11 revisions (55%). One patient suffered from thrombocytopenia. In subgroup B2, 51% showed IVH grade I, whereas severe IVH grades were only present in 22%. 25.9% suffered from thrombocytopenia. Thrombocytopenia was significantly higher in patients who did not develop PHH (p value: 0.002).

CONCLUSION

According to our results, thrombocytopenia could play a decisive role in avoiding development of PHH as a sequel of IVH. We recommend a randomized controlled trial to assess the possible efficacy of antiplatelet drugs in avoiding PHH in this vulnerable group.

Transcriptomic Coupling of PKP2 With Inflammatory and Immune Pathways Endogenous to Adult Cardiac Myocytes

Plakophilin-2 (PKP2) is classically defined as a component of the desmosome. Besides its role in cell–cell adhesion, PKP2 can modulate transcription through intracellular signals initiated at the site of cell–cell contact. Mutations in PKP2 associate with arrhythmogenic right ventricular cardiomyopathy (ARVC). Recent data demonstrate that inflammation plays a key role in disease progression; other results show an abundance of anti-heart antibodies in patients with confirmed diagnosis of ARVC. Here, we test the hypothesis that, in adult cardiac myocytes, PKP2 transcript abundance is endogenously linked to the abundance of transcripts participating in the inflammatory/immune response. Cardiac-specific, tamoxifen (TAM)-activated PKP2-knockout mice (PKP2cKO) were crossed with a RiboTag line to allow characterization of the ribosome-resident transcriptome of cardiomyocytes after PKP2 knockdown. Data were combined with informatics analysis of human cardiac transcriptome using GTEx. Separately, the presence of non-myocyte cells at the time of analysis was assessed by imaging methods. We identified a large number of transcripts upregulated consequent to PKP2 deficiency in myocytes, inversely correlated with PKP2 abundance in human transcriptomes, and part of functional pathways associated with inflammatory/immune responses. Our data support the concept that PKP2 is transcriptionally linked, in cardiac myocytes, to genes coding for host-response molecules even in the absence of exogenous triggers. Targeted anti-inflammatory therapy may be effective in ARVC.

Anticoagulation and bleeding risk in patients with COVID-19

BACKGROUND

There is no current standardized approach to anticoagulation in patients with Coronavirus Disease 2019 (COVID-19) while potential bleeding risks remain. Our study characterizes the patterns of anticoagulation use in COVID-19 patients and the risk of related bleeding.

METHODS

This is a single center retrospective analysis of 355 adult patients with confirmed diagnosis of COVID-19 from March 1 to May 31, 2020. Chi-square was used to analyze the relationship between degree of anticoagulant dose and bleeding events by site. Multivariable logistic regression was used to look at factors associated with inpatient death.

RESULTS

61% of patients were being treated with prophylactic doses of anticoagulation, while 7% and 29% were being treated with sub-therapeutic and therapeutic anticoagulation (TA) doses respectively. In 44% of patients, we found that the decision to escalate the dose of anticoagulation was based on laboratory values characterizing the severity of COVID-19 such as rising D-dimer levels. There were significantly higher rates of bleeding from non-CNS/non-GI sites (p = 0.039) and from any bleeding site overall (p = 0.019) with TA. TA was associated with significantly higher rates of inpatient death (41.6% vs 15.3% p < 0.0001) compared to those without. All patients who developed CNS hemorrhage died p = 0.011. After multivariable logistic regression, only age OR 1.04 95% CI (1.01 to 1.07) p = 0.008 and therapeutic anticoagulation was associated with inpatient mortality OR 6.16 95% CI (2.96 to 12.83) p ≤ 0.0001.

CONCLUSION

The use of TA was significantly associated with increased risk of bleeding. Bleeding in turn exhibited trends towards higher inpatient death among patients with COVID-19. These findings should be interpreted with caution and larger more controlled studies are needed to verify the net effects of anticoagulation in patients with COVID-19.

[Inhibitory Effects of Dabigatran on Airway Inflammation Induced by Lipopolysaccharide in Mice]

Asthma and chronic obstructive pulmonary disease (COPD) are characterised by chronic inflammation in the lung that is associated with airway obstruction. Inhaled therapy with a combination of corticosteroid and a long-acting β₂-agonist is an effective anti-inflammatory medicine for asthma, but in patients with severe asthma and COPD fails to completely control these symptoms with current therapies. The inflammatory process in these diseases, which involves activation of the coagulation and fibrinolytic system in the lung, offers the opportunity for alternative anti-inflammatory therapies. In this study, we investigated the effects of anti-coagulants on lipopolysaccharide (LPS)-induced airway inflammation in mice. A/J mice were exposed to LPS, a bacterial endotoxin, intranasally and accumulation of inflammatory cells, TNF-α, C-X-C motif chemokine (CXCL) 1, and osteopontin in bronchoalveolar lavage fluid (BALF) was monitored by flow cytometry and an enzyme-linked immunosorbent assay. LPS exposure induced airway neutrophilia and accumulation of TNF-α, CXCL1, and osteopontin in BALF. This LPS-induced airway inflammation was not relieved using a corticosteroid, fluticasone propionate (FP), or a direct inhibitor of Factor Xa, rivaroxaban. In contrast, a direct thrombin inhibitor, dabigatran, inhibited LPS-induced airway neutrophilia and decreased inflammatory cytokine production in a dose dependent manner. Furthermore, combination of dabigatran and FP elicited stronger inhibition of LPS-induced airway inflammation. Therefore, these results suggest that dabigatran could be an effective new therapy for severe respiratory diseases.

Particulate Air Pollution, Clock Gene Methylation, and Stroke: Effects on Stroke Severity and Disability

Circadian rhythm disturbances have been consistently associated with the development of several diseases, particularly cardiovascular diseases (CVDs). A central clock in the brain maintains the daily rhythm in accordance with the external environment. At the molecular level, the clock is maintained by “clock genes”, the regulation of which is mainly due to DNA methylation, a molecular mechanism of gene expression regulation, able to react to and be reprogrammed by environmental exposure such as exposure to particulate matter (PM). In 55 patients with a diagnosis of acute ischemic stroke, we showed that PM_2.5 exposure experienced before the event influenced clock genes methylation (i.e., circadian locomotor output cycles protein kaput CLOCK, period 2 PER2, cryprochrome 1 CRY1, Neuronal PAS Domain Protein 2 NPAS2), possibly modulating the patient prognosis after the event, as cryptochrome 1 CRY1 and period 1 PER1 methylation levels were associated with the Rankin score. Moreover, if PM_2.5 annual average was low, CRY1/CRY2 methylation levels were positively associated with the National Institutes of Health Stroke Scale (NIHSS) score, whereas they were negatively associated if PM_2.5 exposure was high. Whether epigenetic changes in clock genes need to be considered as a prognostic marker of stroke or rather a causal agent in stroke development remains to be determined. Further studies are needed to determine the role of clock gene methylation in regulating the response to and recovery after a stroke event.

Fibrin Breakdown Assay

Fibrinolysis is an integral part of the matrix remodeling process that contributes to tissue repair. Fibrin clots are broken down during fibrinolysis in a controlled process. Fibrin degradation products (FDPs) have also been shown to have a role in the regulation of cell growth and are implicated in various vascular diseases. This protocol was designed to quantitatively measure the extent of fibrin breakdown and how this can be adapted as a tool to further investigate the pathway involved in fibrinolysis or fibrin degradation products. Until now, we haven't found an alternative method to analysis fibrinolysis.

α2AP is associated with the development of lupus nephritis through the regulation of plasmin inhibition and inflammatory responses

Introduction

Lupus nephritis (LN) is a common complication of systemic lupus erythematosus (SLE), which is a chronic autoimmune disease. However, the detailed mechanisms underlying this disorder have remained unclear. Alpha2‐antiplasmin (α2AP) is known to perform various functions, such as plasmin inhibition and cytokine production, and to be associated with immune and inflammatory responses.

Methods

We investigated the roles of α2AP in the pathogenesis of LN using a pristane‐induced lupus mouse model.

Results

The levels of plasmin‐α2AP complex and α2AP were elevated in the lupus model mice. In addition, α2AP deficiency attenuated the pristane‐induced glomerular cell proliferation, mesangial matrix expansion, collagen production, fibrin deposition, immunoglobulin G deposition, and proinflammatory cytokine production in the model mice. We also showed that interferon‐γ (IFN‐γ), which is an essential inducer of LN, induced α2AP production through the c‐Jun N‐terminal kinase (JNK) pathway in fibroblasts. In addition, plasmin attenuated the IFN‐γ‐induced proinflammatory cytokine production through the AMPK pathway in macrophages, and α2AP eliminated these effects. Furthermore, we showed that α2AP induced proinflammatory cytokine production through the ERK1/2 and JNK pathways in macrophages.

Conclusion

α2AP regulates the inflammatory responses through plasmin inhibition and proinflammatory cytokine production and is associated with the development of LN. Our findings may be used to develop a novel therapeutic approach for SLE.

Tranexamic acid attenuates inflammatory effect and modulates immune response in primary total knee arthroplasty: a randomized, placebo-controlled, pilot trial

AIMS

To explore the effect of intravenous tranexamic acid (IV-TXA) on inflammation and immune response following primary total knee arthroplasty (TKA).

METHODS

Primary TKA patients (n = 125) were randomized into the following four groups: group A to receive placebo; group B to receive a single dose of 20 mg kg^-1 IV-TXA and 20 mg of intravenous dexamethasone (IV-DXM); group C to receive six doses of IV-TXA (total dosage > 6 g); and group D to receive six doses of IV-TXA combined with three doses of IV-DXM (total dosage = 40 mg). The primary outcomes were C-reactive protein (CRP) and interleukin (IL)-6 levels and the secondary outcomes were complement C3 and C4 and T-cell subset levels, which were measured preoperatively and at 24 h, 48 h, 72 h, and 2 weeks postoperatively.

RESULTS

The postoperative peak CRP and IL-6 levels in group C (93.7 ± 22.2 mg L^-1, 108.8 ± 41.7 pg mL^-1) were lower compared with those in group A (134.7 ± 28.8 mg L^-1, P < 0.01; 161.6 ± 64.4 pg mL^-1, P < 0.01). Groups B and D exhibited significantly lower CRP and IL-6 levels compared with groups A and C at 24 h, 48 h, and 72 h postoperatively (P < 0.05 for all). In group C, complement C3 and C4 levels were higher compared with those in group A at 48 h (0.967 ± 0.127 g L^-1 vs. 0.792 ± 0.100 g L^-1, P < 0.01; 0.221 ± 0.046 g L^-1 vs. 0.167 ± 0.028 g L^-1, P < 0.01) and 72 h (1.050 ± 0.181 g L^-1 vs. 0.860 ± 0.126 g L^-1, P = 0.01; 0.240 ± 0.052 g L^-1 vs. 0.182 ± 0.036 g L^-1, P < 0.01) postoperatively and CD3 and CD4 subset levels were higher compared with those in group B at 24 h postoperatively (66.78 ± 9.29% vs. 56.10 ± 12.47%, P < 0.05; 36.69 ± 5.78% vs. 28.39 ± 8.89%, P < 0.05).

CONCLUSION

Six doses of IV-TXA could attenuate the inflammatory effect, modulate the immune response, and reduce immunosuppression caused by DXM in patients after TKA.

Apixaban exhibits anti-arthritic effects by inhibiting activated factor X-mediated JAK2/STAT3 and MAPK phosphorylation pathways

Activated factor X (FXa) is strongly linked to various inflammatory events. This study aimed to investigate the effect of FXa on janus kinase2/signal transducers and activators of transcription3 (JAK2/STAT3) and mitogen-activated protein kinase (MAPK) phosphorylation in relation to rheumatoid arthritis (RA). It also extends its scope to explore the possible anti-arthritic effects of apixaban, a selective FXa inhibitor. Rats were allocated into normal control; complete Freund's adjuvant (CFA, 0.4 ml/4 days/12 days); FXa (120 µg/kg/day/3 days) and CFA + FXa groups as well as three treated groups including CFA + apixaban; FXa + apixaban and CFA + FXa + apixaban. Apixaban was administered at a dose of 10 mg/kg/12 h for15 days. By the end of the experimental period, tissue samples were collected for the assessment of phosphorylated (p)-JAK2, STAT3, MAPK, matrixmetalloprotein-1 (MMP-1) and protease-activated receptor 2. Furthermore, Serum interleukin-6 (IL-6), platelet-derived growth factor (PDGF), anti-citrullinated protein antibody (ACPA), 8-hydroxy-2'-deoxyguanosine (8-OHdG), plasma level of FXa and prothrombin time were evaluated. In support, histopathological and macroscopical examinations were performed. FXa activated JAK2, STAT3 and MAPK phosphorylation through activation of PAR 2, PDGF and IL-6 and concomitantly led to a significant elevation in ACPA, MMP-1 and 8-OHdG. Apixaban markedly amended FXa-induced changes. Conclusively, the current study revealed that FXa may have a drastic role in RA progression and pathogenesis at least through stimulation of JAK2/STAT3 and MAPK phosphorylation. Furthermore, apixaban exerted robust arthro-protective effects. These beneficial outcomes could be attributed to its ability to impede JAK2/STAT3 and MAPK activation, as well as to its antioxidant property.

Posthemorrhagic hydrocephalus development after germinal matrix hemorrhage: Established mechanisms and proposed pathways

In addition to being the leading cause of morbidity and mortality in premature infants, germinal matrix hemorrhage (GMH) is also the leading cause of acquired infantile hydrocephalus. The pathophysiology of posthemorrhagic hydrocephalus (PHH) development after GMH is complex and vaguely understood, although evidence suggests fibrosis and gliosis in the periventricular and subarachnoid spaces disrupts normal cerebrospinal fluid (CSF) dynamics. Theories explaining general hydrocephalus etiology have substantially evolved from the original bulk flow theory developed by Dr. Dandy over a century ago. Current clinical and experimental evidence supports a new hydrodynamic theory for hydrocephalus development involving redistribution of vascular pulsations and disruption of Starling forces in the brain microcirculation. In this review, we discuss CSF flow dynamics, history and development of theoretical hydrocephalus pathophysiology, and GMH epidemiology and etiology as it relates to PHH development. We highlight known mechanisms and propose new avenues that will further elucidate GMH pathophysiology, specifically related to hydrocephalus.

SERPINB2 and miR-146a/b are coordinately regulated and act in the suppression of psoriasis-associated inflammatory responses in keratinocytes

Psoriasis is a chronic inflammatory skin disease with numerous involved factors. miR-146a and miR-146b (miR-146a/b) are anti-inflammatory miRNAs that are increased in psoriatic skin. SERPINB2 has been shown to be upregulated in the inflammation and infections. Here we aimed to study the relationship between miR-146a/b and SERPINB2 and to delineate the role of SERPINB2 in association of plaque psoriasis. We report increased SERPINB2 expression in the skin of psoriasis patients, which was in a positive relationship with psoriasis severity and in a negative relationship with miR-146a/b in psoriatic lesions. In cultured keratinocytes, both cellular and secreted SERPINB2 levels were strongly induced in response to IFN-γ and TNF-α. Interestingly, SERPINB2 mRNA was downregulated by IL-17A and the combination of TNF-α and IL-17A at time points when miR-146a was increased. The predicted binding site for miR-146a/b in 3' untranslated region of SERPINB2 revealed no activity in luciferase assay, while siRNA silencing of miR-146a/b direct targets IRAK1 and CARD10 resulted in reduced expression of SERPINB2, suggesting that miR-146a/b indirectly control SERPINB2 expression in the skin. The siRNA silencing of SERPINB2 increased the expression of IL-8, CXCL5 and CCL5 and migration of neutrophils revealing its anti-inflammatory role in keratinocytes. Our data together suggest that SERPINB2 and miR-146a/b are part of disease-related network of molecules that are coordinately regulated and act in controlling the inflammatory responses in psoriatic skin.

Ozbek O. Thrombin lag time is increased in children with mild asthma

BACKGROUND

Inflammation and coagulation are closely linked events. Thrombin is the key enzyme in coagulation system and also has roles in inflammation.

OBJECTIVE

The aim of our study was to evaluate thrombin generation in children with mild asthma.

METHODS

Forty-two children with mild asthma and 49 healthy children were included in the study. All patients performed spirometry. Thrombin generation tests (TGT) were performed with a calibrated automated thrombogram (CAT) in children without asthma exacerbation during the last six months. During CAT assay thrombogram curves were obtained. The area under the curve showed endogenous thrombin potentials and indicated the total amount of endogenous thrombin generated; the peak height showed the highest thrombin value, thrombin lag time and time to thrombin peak were measured.

RESULTS

Thrombin lag time was significantly longer in children with asthma (3.98±1.2min) compared to those in the control group (3.29±0.6min) (p<0.01). Children with asthma also had longer thrombin tail time compared to the control group (19.5±8.9min vs. 16.7±2.9min, p=0.02). Thrombin peak was inversely correlated with FEF 25-75 (r=-0.41, p<0.01). Thrombin lag time was inversely correlated with FEF 25-75 (r=-0.39, p<0.01).

CONCLUSION

Inflammation in mild asthma seems to disturb coagulation but this disturbance may not be so strong as to increase thrombin levels and may only affect the initiation phase of thrombin generation.

Bimodal fluorogenic sensing of matrix proteolytic signatures in lung cancer

Optical biosensing based on the activation of fluorescent reporters offers a powerful methodology for the real-time molecular interrogation of pathology. Here we report a first-in-class, bimodal fluorescent reporter strategy for the simultaneous and highly specific detection of two independent proteases (thrombin and matrix metalloproteases (MMPs)) pivotal in the fibroproliferative process surrounding lung cancer, based on a dual, multiplexing, peptide FRET system. This sophisticated synthetic smartprobe, with a molecular weight of 6 kDa, contains two independent fluorophores and quenchers that generate photonic signatures at two specific wavelengths upon activation by target enzymes within human lung cancer tissue.

Coronary thrombosis in acute pancreatitis

The incidence of acute myocardial infarction in the setting of acute pancreatitis is very rare. The recognition of such complex diagnosis may be clinically challenging, as the symptoms of both conditions are often indistinguishable. We report a case in which we encountered both conditions concurrently, and hypothesize that the ambient inflammatory and pro-thrombotic milieu of acute pancreatitis resulted in acute coronary thrombosis despite the absence of significant coronary atherosclerosis. Among multiple coronary imaging modalities currently in use, optimal cohesion tomography provided a unique capability for direct visualization of the coronary thrombus. (1) Inflammatory processes such as acute pancreatitis promote a thrombogenic state. (2) Presentation of acute myocardial infarction is variable and can mimic a variety of medical conditions. (3) Intravascular imaging is emerging as a useful tool in delineating details of intra-coronary pathology not clear on standard fluoroscopy. (4) The above case highlights the likely concurrence of pathologies that follow common pathways such as system-wide inflammation and coagulation. Clinicians must be aware of this uncommon yet very likely possibility and keep a low threshold to perform ECG and cardiac biomarker testing if symptoms are suggestive of a myocardial infarction, even in the presence of a clear alternative diagnosis.

Glucocorticoid-driven transcriptomes in human airway epithelial cells: commonalities, differences and functional insight from cell lines and primary cells

Background

Glucocorticoids act on the glucocorticoid receptor (GR; NR3C1) to resolve inflammation and, as inhaled corticosteroids (ICS), are the cornerstone of treatment for asthma. However, reduced efficacy in severe disease or exacerbations indicates a need to improve ICS actions.

Methods

Glucocorticoid-driven transcriptomes were compared using PrimeView microarrays between primary human bronchial epithelial (HBE) cells and the model cell lines, pulmonary type II A549 and bronchial epithelial BEAS-2B cells.

Results

In BEAS-2B cells, budesonide induced (≥2-fold, P ≤ 0.05) or, in a more delayed fashion, repressed (≤0.5-fold, P ≤ 0.05) the expression of 63, 133, 240, and 257 or 15, 56, 236, and 344 mRNAs at 1, 2, 6, and 18 h, respectively. Within the early-induced mRNAs were multiple transcriptional activators and repressors, thereby providing mechanisms for the subsequent modulation of gene expression. Using the above criteria, 17 (BCL6, BIRC3, CEBPD, ERRFI1, FBXL16, FKBP5, GADD45B, IRS2, KLF9, PDK4, PER1, RGCC, RGS2, SEC14L2, SLC16A12, TFCP2L1, TSC22D3) induced and 8 (ARL4C, FLRT2, IER3, IL11, PLAUR, SEMA3A, SLC4A7, SOX9) repressed mRNAs were common between A549, BEAS-2B and HBE cells at 6 h. As absolute gene expression change showed greater commonality, lowering the cut-off (≥1.25 or ≤ 0.8-fold) within these groups produced 93 induced and 82 repressed genes in common. Since large changes in few mRNAs and/or small changes in many mRNAs may drive function, gene ontology (GO)/pathway analyses were performed using both stringency criteria. Budesonide-induced genes showed GO term enrichment for positive and negative regulation of transcription, signaling, proliferation, apoptosis, and movement, as well as FOXO and PI3K-Akt signaling pathways. Repressed genes were enriched for inflammatory signaling pathways (TNF, NF-κB) and GO terms for cytokine activity, chemotaxis and cell signaling. Reduced growth factor expression and effects on proliferation and apoptosis were highlighted.

Conclusions

While glucocorticoids repress mRNAs associated with inflammation, prior induction of transcriptional activators and repressors may explain longer-term responses to these agents. Furthermore, positive and negative effects on signaling, proliferation, migration and apoptosis were revealed. Since many such gene expression changes occurred in human airways post-ICS inhalation, the effects observed in cell lines and primary HBE cells in vitro may be relevant to ICS in vivo.

Electronic supplementary material

The online version of this article (10.1186/s12920-018-0467-2) contains supplementary material, which is available to authorized users.

Proteases: Pivot Points in Functional Proteomics

Proteases drive the life cycle of all proteins, ensuring the transportation and activation of newly minted, would-be proteins into their functional form while recycling spent or unneeded proteins. Far from their image as engines of protein digestion, proteases play fundamental roles in basic physiology and regulation at multiple levels of systems biology. Proteases are intimately associated with disease and modulation of proteolytic activity is the presumed target for successful therapeutics. "Proteases: Pivot Points in Functional Proteomics" examines the crucial roles of proteolysis across a wide range of physiological processes and diseases. The existing and potential impacts of proteolysis-related activity on drug and biomarker development are presented in detail. All told the decisive roles of proteases in four major categories comprising 23 separate subcategories are addressed. Within this construct, 15 sets of subject-specific, tabulated data are presented that include identification of proteases, protease inhibitors, substrates, and their actions. Said data are derived from and confirmed by over 300 references. Cross comparison of datasets indicates that proteases, their inhibitors/promoters and substrates intersect over a range of physiological processes and diseases, both chronic and pathogenic. Indeed, "Proteases: Pivot Points …" closes by dramatizing this very point through association of (pro)Thrombin and Fibrin(ogen) with: hemostasis, innate immunity, cardiovascular and metabolic disease, cancer, neurodegeneration, and bacterial self-defense.

A bronchoprotective role for Rgs2 in a murine model of lipopolysaccharide-induced airways inflammation

Background

Asthma exacerbations are associated with the recruitment of neutrophils to the lungs. These cells release proteases and mediators, many of which act at G protein-coupled receptors (GPCRs) that couple via Gq to promote bronchoconstriction and inflammation. Common asthma therapeutics up-regulate expression of the regulator of G protein signalling (RGS), RGS2. As RGS2 reduces signaling from Gq-coupled GPCRs, we have defined role(s) for this GTPase-activating protein in an acute neutrophilic model of lung inflammation.

Methods

Wild type and Rgs2^−/− C57Bl6 mice were exposed to nebulized lipopolysaccharide (LPS). Lung function (respiratory system resistance and compliance) was measured using a SCIREQ flexivent small animal ventilator. Lung inflammation was assessed by histochemistry, cell counting and by cytokine and chemokine expression in bronchoalveolar lavage (BAL) fluid.

Results

Lipopolysaccharide inhalation induced transient airways hyperreactivity (AHR) and neutrophilic lung inflammation. While AHR and inflammation was greatest 3 h post-LPS exposure, BAL neutrophils persisted for 24 h. At 3 h post-LPS inhalation, multiple inflammatory cytokines (CSF2, CSF3, IL6, TNF) and chemokines (CCL3, CCL4, CXCL1, CXCL2) were highly expressed in the BAL fluid, prior to declining by 24 h. Compared to wild type counterparts, Rgs2^−/− mice developed significantly greater airflow resistance in response to inhaled methacholine (MCh) at 3 h post-LPS exposure. At 24 h post-LPS exposure, when lung function was recovering in the wild type animals, MCh-induced resistance was increased, and compliance decreased, in Rgs2^−/− mice. Thus, Rgs2^−/− mice show AHR and stiffer lungs 24 h post-LPS exposure. Histological markers of inflammation, total and differential cell counts, and major cytokine and chemokine expression in BAL fluid were similar between wild type and Rgs2^−/− mice. However, 3 and 24 h post-LPS exposure, IL12B expression was significantly elevated in BAL fluid from Rgs2^−/− mice compared to wild type animals.

Conclusions

While Rgs2 is bronchoprotective in acute neutrophilic inflammation, no clear anti-inflammatory effect was apparent. Nevertheless, elevated IL12B expression in Rgs2^−/− animals raises the possibility that RGS2 could dampen Th1 responses. These findings indicate that up-regulation of RGS2, as occurs in response to inhaled corticosteroids and long-acting β₂-adrenoceptor agonists, may be beneficial in acute neutrophilic exacerbations of airway disease, including asthma.

Electronic supplementary material

The online version of this article (10.1186/s13223-018-0266-5) contains supplementary material, which is available to authorized users.

The intertwined fates of inflammation and coagulation in glioma

Inflammation and coagulation are two intertwined pathways with evolutionary ties being traced back to the hemocyte, a single cell type in invertebrates that has functions in both the inflammatory and coagulation pathways. These systems have functioned together throughout evolution to provide a solid defence against infection, damaged cells and irritants. While these systems work in harmony the majority of the time, they can also become dysregulated or corrupted by tumours, enhancing tumour proliferation, invasion, dissemination and survival. This review aims to give a brief overview of how these systems work in harmony and how dysregulation of these systems aids in the development and progression of cancer, using glioma as an example.

Pro-inflammatory response and hemostatic disorder induced by venom of the coral snake Micrurus tener tener IN C57BL/6 mice

Micrurus venoms are known to induce mainly neurotoxicity in victims. However, other manifestations, including hemorrhage, edema, myotoxicity, complement activation, and hemostatic activity have been reported. In order to develop a more complete pharmacological profile of these venoms, inflammatory responses and hemostasis were evaluated in C57BL/6 mice treated with a sub-lethal dose of M. t. tener (Mtt) venom (8 μg/mouse), inoculated intraperitoneally. The venom induced moderate bleeding into the abdominal cavity and lungs, as well as infiltration of leukocytes into the liver. After 30 min, the release of pro-inflammatory mediators (TNF-α, IL-6, and NO) were observed, being most evident at 4 h. There was a decrease in hemoglobin and hematocrit levels at 72 h, a prolongation in coagulation times (PT and aPTT), a decrease in the fibrinogen concentration and an increase in fibrinolytic activity. In this animal model, it was proposed that Mtt venom induces inflammation with the release of mediators such as TNF-α, in response to the toxins. These mediators may activate hemostatic mechanisms, producing systemic fibrinolysis and hemorrhage. These findings suggest alternative treatments in Micrurus envenomations in which neurotoxic manifestations do not predominate.

[A plasminogen regulation system in brain tumors]

INTRODUCTION

Tumor progression and neovascularization during malignant processes are believed to be associated with plasminogen activators and the PAI-1 inhibitor, but their role and interactions in various types of brain tumors have been studied insufficiently.

AIM

To conduct a comparative study of plasminogen regulation in optic nerve sheath meningiomas, glioblastomas, and brain metastases of breast cancer, as well as in perifocal tissues surrounding the tumors.

MATERIAL AND METHODS

Tumors and perifocal areas of 19 breast cancer (BC) metastases, 24 glioblastomas, and 13 meningiomas without perifocal edema were investigated by ELISA in 56 patients aged 35-72 years. Histological control was carried out in each case.

RESULTS

Significant differences were found in the levels of urokinase (uPA), tissue plasminogen activator (tPA), and PAI-1 inhibitor between glioblastomas and breast cancer metastases and the histologically unaltered (relatively intact) tissue around meningioma lesions (p≤0.05 in all cases). The levels of uPA-AG and uPA-act in meningioma were higher than those in the relatively intact tissue, while the levels of both tPA forms were reduced. The levels of uPA-AG and uPA-act in both malignant tumors and their perifocal areas were elevated compared to those in the relatively intact tissue. The levels of both tPA forms were reduced in all other tissues, except for glioblastoma. The level of PAI-1 inhibitor in malignant tissues was higher (being predominant in tumors) compared to that in the intact tissue surrounding meningioma, as well as relative to that in meningioma. The study proves that uPA and its inhibitor PAI-1 are directly involved in the metabolism of malignant gliomas and brain metastases of breast cancer. The role of tPA is to protect meningiomas; tPA activation in malignant brain tumors is suppressed.