The interactions between inflammation and coagulation

Point-of-care diagnosis and monitoring of fibrinolysis resistance in the critically ill: results from a feasibility study

BACKGROUND

Fibrinolysisis is essential for vascular blood flow maintenance and is triggered by endothelial and platelet release of tissue plasminogen activator (t-PA). In certain critical conditions, e.g. sepsis, acute respiratory failure (ARF) and trauma, the fibrinolytic response is reduced and may lead to widespread thrombosis and multi-organ failure. The mechanisms underpinning fibrinolysis resistance include reduced t-PA expression and/or release, reduced t-PA and/or plasmin effect due to elevated inhibitor levels, increased consumption and/or clearance. This study in critically ill patients with fibrinolysis resistance aimed to evaluate the ability of t-PA and plasminogen supplementation to restore fibrinolysis with assessment using point-of-care ClotPro viscoelastic testing (VET).

METHODS

In prospective, observational studies, whole-blood ClotPro VET evaluation was carried out in 105 critically ill patients. In 32 of 58 patients identified as fibrinolysis-resistant (clot lysis time > 300 s on the TPA-test: tissue factor activated coagulation with t-PA accelerated fibrinolysis), consecutive experimental whole-blood VET was carried out with repeat TPA-tests spiked with additional t-PA and/or plasminogen and the effect on lysis time determined. In an interventional study in a patient with ARF and fibrinolysis resistance, the impact of a 24 h intravenous low-dose alteplase infusion on coagulation and fibrinolysis was prospectively monitored using standard ClotPro VET.

RESULTS

Distinct response groups emerged in the ex vivo experimental VET, with increased fibrinolysis observed following supplementation with (i) t-PA only or (ii) plasminogen and t-PA. A baseline TPA-test lysis time of > 1000 s was associated with the latter group. In the interventional study, a gradual reduction (25%) in serial TPA-test lysis times was observed during the 24 h low-dose alteplase infusion.

CONCLUSIONS

ClotPro viscoelastic testing, the associated TPA-test and the novel experimental assays may be utilised to (i) investigate the potential mechanisms of fibrinolysis resistance, (ii) guide corrective treatment and (iii) monitor in real-time the treatment effect. Such a precision medicine and personalised treatment approach to the management of fibrinolysis resistance has the potential to increase treatment benefit, while minimising adverse events in critically ill patients.

TRIAL REGISTRATION

VETtiPAT-ARF, a clinical trial evaluating ClotPro-guided t-PA (alteplase) administration in fibrinolysis-resistant patients with ARF, is ongoing (ClinicalTrials.gov NCT05540834 ; retrospectively registered September 15th 2022).

Computational modeling of hypercoagulability in COVID-19

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected more than 100 million people worldwide and claimed millions of lives. While the leading cause of mortality in COVID-19 patients is the hypoxic respiratory failure from acute respiratory distress syndrome, there is accumulating evidence that shows excessive coagulation also increases the fatalities in COVID-19. Thus, there is a pressing demand to understand the association between COVID-19-induced hypercoagulability and the extent of formation of undesired blood clots. Mathematical modeling of coagulation has been used as an important tool to identify novel reaction mechanisms and to identify targets for new drugs. Here, we employ the coagulation factor data of COVID-19 patients reported from published studies as inputs for two mathematical models of coagulation to identify how the concentrations of coagulation factors change in these patients. Our simulation results show that while the levels of many of the abnormal coagulation factors measured in COVID-19 patients promote the generation of thrombin and fibrin, two key components of blood clots, the increased level of fibrinogen and then the reduced level of antithrombin are the factors most responsible for boosting the level of fibrin and thrombin, respectively. Altogether, our study demonstrates the potential of mathematical modeling to identify coagulation factors responsible for the increased clot formation in COVID-19 patients where clinical data is scarce.

Venous Thromboembolism Following Discharge from Hospital in Patients Admitted for Inflammatory Bowel Disease

BACKGROUND AND AIMS

Patients admitted to hospital with inflammatory bowel disease[IBD] are at increased risk of venous thromboembolism[VTE]. This study aims to identify IBD patients at increased VTE risk on hospital discharge and to develop a risk scoring system to recognise them.

METHODS

Hospital episode statistics data were used to identify all patients admitted with IBD as an emergency or electively for surgery. All patients with VTE within 90 days of hospital discharge were identified. A multilevel logistic regression model was used to identify patient- and admission-level factors associated with VTE. A scoring system to identify patients at higher risk for VTE was constructed.

RESULTS

A total of 201 779 admissions in 101 966 patients were included. The rate of VTE within 90 days was 17.2 per 1000 patient-years at risk and was highest in patients admitted as an emergency who underwent surgery[36.9]. VTE was associated with: female sex (odds ratio 0.65 [95% confidence interval 0.53-0.80], p <0.001); increasing age [49-60 years] (4.67 [3.36-6.49], p <0.001); increasing length of hospital stay [>10 days] (3.80 [2.80-5.15], p <0.001); more than two hospital admissions in previous 3 months (2.23 [1.60-3.10], p <0.001); ulcerative colitis (1.48 [1.21-1.82], p <0.001); and emergency admission including surgery (1.59 [1.12-2.27], p = 0.010); or emergency admission not including surgery (1.59 [1.08-2.35], p = 0.019) compared with elective surgery. A score >12 in the VTE scoring system gave a positive predictive value [PPV] of VTE of 1%. The area under the curve [AUC] was 0.714 [95% CI 0.70-0.73].

CONCLUSION

IBD patients admitted to hospital with a prolonged length of stay, increasing age, male sex, or as an emergency were at increased risk of VTE following discharge. Higher-risk patients were identifiable by a VTE risk scoring system.

Inflammation balance in skeletal muscle damage and repair

Responding to tissue injury, skeletal muscles undergo the tissue destruction and reconstruction accompanied with inflammation. The immune system recognizes the molecules released from or exposed on the damaged tissue. In the local minor tissue damage, tissue-resident macrophages sequester pro-inflammatory debris to prevent initiation of inflammation. In most cases of the skeletal muscle injury, however, a cascade of inflammation will be initiated through activation of local macrophages and mast cells and recruitment of immune cells from blood circulation to the injured site by recongnization of damage-associated molecular patterns (DAMPs) and activated complement system. During the inflammation, macrophages and neutrophils scavenge the tissue debris to release inflammatory cytokines and the latter stimulates myoblast fusion and vascularization to promote injured muscle repair. On the other hand, an abundance of released inflammatory cytokines and chemokines causes the profound hyper-inflammation and mobilization of immune cells to trigger a vicious cycle and lead to the cytokine storm. The cytokine storm results in the elevation of cytolytic and cytotoxic molecules and reactive oxygen species (ROS) in the damaged muscle to aggravates the tissue injury, including the healthy bystander tissue. Severe inflammation in the skeletal muscle can lead to rhabdomyolysis and cause sepsis-like systemic inflammation response syndrome (SIRS) and remote organ damage. Therefore, understanding more details on the involvement of inflammatory factors and immune cells in the skeletal muscle damage and repair can provide the new precise therapeutic strategies, including attenuation of the muscle damage and promotion of the muscle repair.

Effect of early vs. late maturing sire lines and creep feeding on the cortisol response, intestinal permeability, and growth performance of nursery and finishing pigs

A total of 21 litters (11 early and 10 late maturing Duroc × DNA 241) resulting in 241 pigs were used in 170 d trial to determine the effect of sire lines selected for either early or late maturing growth rates and creep feeding on the cortisol concentration, intestinal permeability, and growth performance of nursery and finishing pigs. Treatments were arranged in a 2 × 2 factorial with main effect of Duroc sire line (early or late maturing) and creep feeding (with or without). Creep feed was provided for 14 d prior to weaning. After weaning (approximately 21 d of age; initially 6.4 kg), no interactions were observed for blood cortisol. However, blood cortisol levels were increased (P = 0.011) in late maturing pigs compared to early maturing pigs. A lower percentage (P < 0.001) of early maturing pigs lost weight 3 d post-weaning compared to late maturing pigs. Likewise, early maturing pigs had improved (P < 0.001) average daily gain (ADG) and average daily feed intake (ADFI) during the first 3 d in the nursery and also had increased ADFI (P < 0.001) from days 2 to 14 in the nursery. Creep feeding had no effect on initial nursery performance. On day 7, after a 2-h fast, a subsample of pigs was administered an oral gavage of lactulose and mannitol dissolved in distilled water. No differences by sire line, creep feeding, or their interactions were observed in lactulose:mannitol ratio. For overall nursery growth performance, an interaction was observed for ADG (P = 0.007) and ADFI (P < 0.001), with creep feed providing a benefit in late maturing pigs, but not in early maturing pigs. Early maturing pigs had poorer gain-to-feed ratio (G:F) (P < 0.001) than late maturing pigs. For overall finishing performance, an interaction was observed for ADG (P = 0.037) and ADFI (P = 0.007), with creep feed providing a benefit in late maturing pigs, but not in early maturing pigs. This resulted in an interaction for final body weight (P = 0.005), with late maturing pigs that did not receive creep feed having decreased market weights (P ≤ 0.003) compared to the other treatments. In summary, early maturing pigs had decreased cortisol concentration at weaning and improved ADG and ADFI until approximately 100 kg, at which point late maturing pigs began to exhibit greater ADG. Late maturing pigs had improved G:F from 46 d of age until market. Interestingly, creep feeding late maturing pigs resulted in increased day 170 weight compared with providing no creep feed, whereas creep feed did not impact early maturing pigs (sire line × creep feed interaction, P < 0.005).

α1-Adrenergic Stimulation Increases Platelet Adhesion to Endothelial Cells Mediated by TRPC6

Stimulation of a1-adrenergic nervous system is increased during systemic inflammation and other pathological conditions with the consequent adrenergic receptors (ARs) activation. It has been reported that a1-stimulation contributes to coagulation since a1-AR blockers inhibit coagulation and its organic consequences. Also, coagulation induced by a1-AR stimulation can be greatly decreased using a1-AR blockers. In health, endothelial cells (ECs) perform anticoagulant actions at cellular and molecular level. However, during inflammation, ECs turn dysfunctional promoting a procoagulant state. Endothelium-dependent coagulation progresses at cellular and molecular levels, promoting endothelial acquisition of procoagulant properties to potentiate coagulation by means of prothrombotic and antifibrinolytic proteins expression increase in ECs releasing them to circulation, the thrombus formation is strengthened. Calcium signaling is a main feature of coagulation. Inhibition of ion channels involved in Ca²⁺ entry severely decreases coagulation. The transient receptor potential canonical 6 (TRPC6) is a non-selective Ca²⁺-permeable ion channel. TRPC6 activity is induced by diacylglycerol, suggesting that is regulated by a1-ARs. Furthermore, a1-ARs stimulation elicits a TRPC-like current in rat mesenteric artery smooth muscle and mesangial cells. However, whether TRPC6 could promote an ECs-mediated platelet adhesion induced by a1-adrenergic stimulation is currently not known. Therefore, the aim of this study was to examine if the TRPC6 calcium channel mediates platelet adhesion induced by a1-adrenergic stimulation. Our results suggest that platelet adhesion to ECs is enhanced by the a1-adrenergic stimulation evoked by phenylephrine mediated by TRPC6 activity. We conclude that TRPC6 is a molecular determinant in platelet adhesion to ECs with implications in systemic inflammatory diseases treatment.

Anticoagulant therapies against sepsis-induced disseminated intravascular coagulation

Disseminated intravascular coagulation (DIC) is a frequent but lethal complication in sepsis. Anticoagulant therapies, such as heparin, antithrombin, activated protein C, and recombinant human-soluble thrombomodulin, were expected to regulate the progression of coagulopathy in sepsis. Although a number of randomized controlled trials (RCTs) have evaluated the survival effects of these therapies over the past few decades, there remains no consistent evidence showing a significant survival benefit of anticoagulant therapies. Currently, anticoagulant therapies are not conducted as a standard treatment against sepsis in many countries and regions. However, most of these RCTs were performed overall in patients with sepsis but not in those with sepsis-induced DIC, who were theoretically the optimal target population of anticoagulants. Actually, multiple lines of evidence from observational studies and meta-analyses of the RCTs have suggested that anticoagulant therapies might reduce mortality only when used in septic DIC. In addition, the severity of illness is another essential factor that maximally affects the efficacy of the therapy. Therefore, to provide evidence on the true effect of anticoagulant therapies, the next RCTs must be designed to enroll only patients with sepsis-induced overt DIC and a high severity of illness. To prepare these future RCTs, a novel scientific infrastructure for accurate detection of patients who can receive maximal benefit from anticoagulant therapies also needs to be established.

The pathogenesis and therapeutic strategies of heat stroke-induced liver injury

Heat stroke (HS) is a life-threatening systemic disease characterized by an elevated core body temperature of more than 40 ℃ and subsequent multiple organ dysfunction syndrome. With the growing frequency of global heatwaves, the incidence rate of HS has increased significantly, which has caused a huge burden on people's lives and health. Liver injury is a well-documented complication of HS and usually constitutes the direct cause of patient death. In recent years, a lot of research has been carried out on the pathogenesis and treatment strategies of HS-induced liver injury. In this review, we summarized the important pathogenesis of HS-induced liver injury that has been confirmed so far. In addition to the comprehensive effect of systemic factors such as heat cytotoxicity, coagulopathy, and systemic inflammatory response syndrome, excessive hepatocyte cell pyroptosis, dysfunction of Kupffer cells, abnormal expression of heat shock protein expression, and other factors are also involved in the pathogenesis of HS-induced liver injury. Furthermore, we have also established the current therapeutic strategies for HS-induced liver injury. Our study is of great significance in promoting the understanding of the pathogenesis and treatment of HS-induced liver injury.

Role of Oxidative Stress in Peyronie's Disease: Biochemical Evidence and Experiences of Treatment with Antioxidants

BACKGROUND

Peyronie's disease (PD) is a chronic inflammatory condition affecting adult males, involving the tunica albuginea of the corpora cavernosa of the penis. PD is frequently associated with penile pain, erectile dysfunction, and a secondary anxious-depressive state. The etiology of PD has not yet been completely elucidated, but local injury is generally recognized to be a triggering factor. It has also been widely proven that oxidative stress is an essential, decisive component in all inflammatory processes, whether acute or chronic. Current conservative medical treatment comprises oral substances, penile injections, and physical therapy.

AIM

This article intends to show how antioxidant therapy is able to interfere with the pathogenetic mechanisms of the disease.

METHOD

This article consists of a synthetic narrative review of the current scientific literature on antioxidant therapy for this disease.

RESULTS

The good results of the antioxidant treatment described above also prove that the doses used were adequate and the concentrations of the substances employed did not exceed the threshold at which they might have interacted negatively with the mechanisms of the redox regulation of tissue.

CONCLUSIONS

We believe new, randomized, controlled studies are needed to confirm the efficacy of treatment with antioxidants. However, we consider the experiences of antioxidant treatment which can already be found in the literature useful for the clinical practice of urologists in the treatment of this chronic inflammatory disease.

Prothrombotic state, endothelial injury, and echocardiographic changes in non-active sarcoidosis patients

Sarcoidosis is a multisystem inflammatory granulomatous disease of unknown cause that most commonly affects lungs and lymph nodes, with frequent yet asymptomatic cardiac involvement. The epidemiologically associated cardiovascular risk suggests an underlying prothrombotic state and endothelial dysfunction, currently understudied in the available literature. Therefore, we aimed to investigate prothrombotic plasma properties together with selected echocardiographic and laboratory biomarkers of cardiovascular injury in that disease. N = 53 patients with pulmonary sarcoidosis in clinical remission and N = 66 matched controls were assessed for inflammatory and endothelial injury biomarkers, plasma thrombin generation profile, and echocardiographic and lung function parameters. Sarcoidosis cases had impaired systolic and diastolic left ventricular function, higher concentrations of inflammatory markers, D-dimer and factor VIII activity compared to the controls. The coexistence of extrapulmonary disease was associated with elevated circulating vascular cell adhesion molecule 1, while cases with hypercalcemia had higher thrombomodulin concentration. Sarcoidosis was characterized by the unfavorably altered thrombin generation profile, reflected by the 16% higher endogenous thrombin potential (ETP), 24% increased peak thrombin concentration, and 12% shorter time to thrombin peak in comparison to the control group. ETP was higher in cases with proxies of pulmonary restriction, extrapulmonary-extracutaneous manifestation, and need for corticosteroids use. Despite the clinical remission, sarcoidosis is related to prothrombotic plasma properties and signs of endothelial injury, likely contributing to the higher risk of cardiovascular events. In addition, subclinical cardiac involvement may play an additional role, although further clinical and experimental studies are needed to verify these findings.

COVID-19 Induces Cytokine Storm and Dysfunctional Hemostasis

BACKGROUND

Infection with SARS-CoV-2 leads to COVID-19 which can manifest in various ways from asymptomatic or mild disease to acute respiratory distress syndrome. The occurrence of dysregulated inflammatory responses in the form of a cytokine storm has been reported in patients with severe COVID-19. Infection can also lead to dysfunctional hemostasis reflected in elevated circulating D-dimer and fibrin degradation products. Components of hemostasis and the immune system during infection can result in a procoagulation and/or proinflammatory state. The interplay between coagulation and inflammation has been elucidated in a number of diseases.

OBJECTIVE

In this article, we discuss the occurrence of cytokine storms and dysfunctional hemostasis induced in COVID-19.

METHODS

This review was written using literature from the past two to three years investigating coagulation and inflammation in COVID-19. Additional literature, both clinical and basic research, related to pathogen infection and host responses were also considered in this review.

RESULTS/CONCLUSIONS

Infection with SARS-CoV-2 can lead to dysregulated inflammatory responses that may be detrimental to the host. The increased expression of various inflammatory factors can ultimately create an environment that promotes thrombosis.

Long-term survival analysis of free flap reconstruction in patients with collagen vascular disorders

BACKGROUND

Collagen vascular disorders (CVD) are inflammatory diseases that can affect the blood vessels and soft tissues. Patients with CVD are often immunosuppressed, prone to hyper-coagulation, and represent a challenging patient cohort for free tissue transfer.

METHODS

A retrospective review of patients with CVD who underwent free flap reconstructions from 2000-2020 was performed at our institution. Inclusion criteria were patients 18 years old or older with the clinical diagnosis of CVD, including rheumatoid arthritis, Raynaud phenomenon, systemic lupus erythematosus, scleroderma, and sarcoidosis. A time-to-event analysis was performed to identify predictors of surgical complications.

RESULTS

A total of 78 patients and 96 free flaps were included. The most common CVD were rheumatoid arthritis (n=36) and Raynaud's phenomenon (n=9). Type of flap included abdominal-based flap (26%), trunk-based flaps (32.3%), and extremity-based flaps (19.8%). The mean age was 56.7±14.6 years, and the mean BMI was 27.5±5.9 kg/m2. Antibody positivity was present in 25.6% of patients; 59% were on chronic steroids, 6.4% were on chronic anticoagulation, 35.9% had radiation therapy, and 29.5% had chemotherapy. Nine percent of patients had a history of prior flap loss, and 11.5% had a history of DVT or arterial thrombosis. The flap loss rate was 3.8%. Steroid treatment was associated with an increased risk of major complications after adjusting for the type of flap HR 2.5(1.3-4.9), p= 0.01. Specifically associated with a higher risk of cellulitis, OR 5.1 (1.1-24.5), p=0.02, and abscess, OR 5.7 (1.2-27.1), p=0.01.

CONCLUSION

Free flap reconstruction can be safely performed in patients with CVD. Perioperative optimization of steroids is important to promote wound healing and stabilize disease activity.

Innate immunity, cytokine storm, and inflammatory cell death in COVID-19

The innate immune system serves as the first line of defense against invading pathogens; however, dysregulated innate immune responses can induce aberrant inflammation that is detrimental to the host. Therefore, careful innate immune regulation is critical during infections. The coronavirus disease 2019 (COVID-19) pandemic is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has resulted in global morbidity and mortality as well as socio-economic stresses. Innate immune sensing of SARS-CoV-2 by multiple host cell pattern recognition receptors leads to the production of various pro-inflammatory cytokines and the induction of inflammatory cell death. These processes can contribute to cytokine storm, tissue damage, and acute respiratory distress syndrome. Here, we discuss the sensing of SARS-CoV-2 to induce innate immune activation and the contribution of this innate immune signaling in the development and severity of COVID-19. In addition, we provide a conceptual framework for innate immunity driving cytokine storm and organ damage in patients with severe COVID-19. A better understanding of the molecular mechanisms regulated by innate immunity is needed for the development of targeted modalities that can improve patient outcomes by mitigating severe disease.

von Willebrand factor links primary hemostasis to innate immunity

The plasma multimeric glycoprotein von Willebrand factor (VWF) plays a critical role in primary hemostasis by tethering platelets to exposed collagen at sites of vascular injury. Recent studies have identified additional biological roles for VWF, and in particular suggest that VWF may play an important role in regulating inflammatory responses. However, the molecular mechanisms through which VWF exerts its immuno-modulatory effects remain poorly understood. In this study, we report that VWF binding to macrophages triggers downstream MAP kinase signaling, NF-κB activation and production of pro-inflammatory cytokines and chemokines. In addition, VWF binding also drives macrophage M1 polarization and shifts macrophage metabolism towards glycolysis in a p38-dependent manner. Cumulatively, our findings define an important biological role for VWF in modulating macrophage function, and thereby establish a novel link between primary hemostasis and innate immunity.

Recombinant thrombomodulin may protect cardiac capillary endothelial glycocalyx through promoting Glypican-1 expression under experimental endotoxemia

Introduction

Myocardial dysfunction occurs in patients with sepsis due to vascular endothelial injury. Recombinant human thrombomodulin (rhTM) attenuates vascular endothelial injuries through endothelial glycocalyx (eGC) protection.

Hypothesis

We hypothesized that rhTM attenuates myocardial dysfunction via the inhibition of vascular endothelial injury during sepsis.

Methods

Ten-week-old male C57BL6 mice were injected intraperitoneally with 20 mg/kg of lipopolysaccharide (LPS). In rhTM-treated mice, rhTM was injected intraperitoneally at 3 and 24 h after LPS injection. Saline was injected intraperitoneally as control. To assess for eGC injury, intensity score was measured 48 h after the LPS injection. To confirm vascular endothelial injuries, ultrastructural analysis was performed using scanning (SEM) and transmission electron microscopy (TEM).

Results

The survival rate of the rhTM group at 48 h after LPS injection was significantly higher than that of the control group (68% vs. 17%, p < 0.05). The serum level of troponin I in the rhTM group was lower than that in the control (2.2 ± 0.4 ng/dL vs 9.4 ± 1.1 ng/dL, p < 0.05). The expression of interleukin-6 (IL-6) was attenuated in the rhTM-treated group than in the control (65.3 ± 15.3 ng/mL vs 226.3 ± 19.4 ng/mL, p < 0.05). The serum concentration of syndecan-1, a marker of glycocalyx damage, was significantly decreased 48 h post-administration of LPS in the rhTM-treated group than in the control group. In ultrastructural analysis using SEM and TEM, eGC peeled off from the surface of the capillary lumen in the control. Conversely, the eGC injury was attenuated in the rhTM group. Gene set enrichment analysis revealed that osteomodulin, osteoglycin proline/arginine-rich end leucine-rich repeat protein, and glypican-1, which are proteoglycans, were preserved by rhTM treatment. Their protein expression was retained in endothelial cells.

Conclusion

rhTM attenuates sepsis-induced myocardial dysfunction via eGC protection.

Immune response induced by novel coronavirus infection

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus (SARS-CoV)-2 has been prominent around the world since it was first discovered, affecting more than 100 million people. Although the symptoms of most infected patients are not serious, there is still a considerable proportion of patients who need hospitalization and even develop fatal symptoms such as cytokine storms, acute respiratory distress syndrome and so on. Cytokine storm is usually described as a collection of clinical manifestations caused by overactivation of the immune system, which plays an important role in tissue injury and multiorgan failure. The immune system of healthy individuals is composed of two interrelated parts, the innate immune system and the adaptive immune system. Innate immunity is the body's first line of defense against viruses; it can quickly perceive viruses through pattern recognition receptors and activate related inflammatory pathways to clear pathogens. The adaptive immune system is activated by specific antigens and is mainly composed of CD4+ T cells, CD8+ T cells and B cells, which play different roles in viral infection. Here, we discuss the immune response after SARS-CoV-2 infection. In-depth study of the recognition of and response of innate immunity and adaptive immunity to SARS-CoV-2 will help to prevent the development of critical cases and aid the exploration of more targeted treatments.

Dysregulated Hemostasis and Immunothrombosis in Cerebral Cavernous Malformations

Cerebral cavernous malformation (CCM) is a neurovascular disease that affects 0.5% of the general population. For a long time, CCM research focused on genetic mutations, endothelial junctions and proliferation, but recently, transcriptome and proteome studies have revealed that the hemostatic system and neuroinflammation play a crucial role in the development and severity of cavernomas, with some of these publications coming from our group. The aim of this review is to give an overview of the latest molecular insights into the interaction between CCM-deficient endothelial cells with blood components and the neurovascular unit. Specifically, we underscore how endothelial dysfunction can result in dysregulated hemostasis, bleeding, hypoxia and neurological symptoms. We conducted a thorough review of the literature and found a field that is increasingly poised to regard CCM as a hemostatic disease, which may have implications for therapy.

Venous Thromboembolism in Rheumatoid Arthritis: The Added Effect of Disease Activity to Traditional Risk Factors

Many epidemiological studies have shown an increased risk of venous thromboembolism (VTE) in patients with rheumatoid arthritis (RA). RA and VTE share some background factors, such as increasing age, smoking, and obesity. At the same time, other VTE factors, such as knee replacement and oral contraceptive pills, occur commonly in RA patients. In addition, the chronic inflammatory state of RA might hypothetically lead to endothelial injury and a hypercoagulable state. Two critical pathophysiological pathways lead to VTE. Recently, concerns increased about the increased risk of VTE in patients using Janus Kinase inhibitors. This review aims at reviewing the risk of VTE in RA and the role of traditional risk factors and disease-related inflammation and develops a conceptual framework that describes the interaction between these factors.

LPS-Induced Coagulation and Neuronal Damage in a Mice Model Is Attenuated by Enoxaparin

Background. Due to the interactions between neuroinflammation and coagulation, the neural effects of lipopolysaccharide (LPS)-induced inflammation (1 mg/kg, intraperitoneal (IP), n = 20) and treatment with the anti-thrombotic enoxaparin (1 mg/kg, IP, 15 min, and 12 h following LPS, n = 20) were studied in C57BL/6J mice. Methods. One week after LPS injection, sensory, motor, and cognitive functions were assessed by a hot plate, rotarod, open field test (OFT), and Y-maze. Thrombin activity was measured with a fluorometric assay; hippocampal mRNA expression of coagulation and inflammation factors were measured by real-time-PCR; and serum neurofilament-light-chain (NfL), and tumor necrosis factor-α (TNF-α) were measured by a single-molecule array (Simoa) assay. Results. Reduced crossing center frequency was observed in both LPS groups in the OFT (p = 0.02), along with a minor motor deficit between controls and LPS indicated by the rotarod (p = 0.057). Increased hippocampal thrombin activity (p = 0.038) and protease-activated receptor 1 (PAR1) mRNA (p = 0.01) were measured in LPS compared to controls, but not in enoxaparin LPS-treated mice (p = 0.4, p = 0.9, respectively). Serum NfL and TNF-α levels were elevated in LPS mice (p < 0.05) and normalized by enoxaparin treatment. Conclusions. These results indicate that inflammation, coagulation, neuronal damage, and behavior are linked and may regulate each other, suggesting another pharmacological mechanism for intervention in neuroinflammation.

Restoration of vascular endothelial integrity by mesenchymal stromal/stem cells in debilitating virus diseases

Endothelial dysfunction is one of the key cornerstone complications of emerging and re-emerging viruses which lead to vascular leakage and a high mortality rate. The mechanism that regulates the origin of endothelial dysregulation is not completely elucidated. Currently, there are no potential pharmacological treatments and curable management for such diseases. In this sense, mesenchymal stromal/stem cells (MSCs) has been emerging to be a promising therapeutic strategy in restoring endothelial barrier function in various lung disease, including ALI and ARDS. The mechanism of the role of MSCs in restoring endothelial integrity among single-strand RNA (ssRNA) viruses that target endothelial cells remains elusive. Thus, we have discussed the therapeutic role of MSCs in restoring vascular integrity by (i) inhibiting the metalloprotease activity thereby preventing the cleavage of tight junction proteins, which are essential for maintaining membrane integrity (ii) possessing antioxidant properties which neutralize the excessive ROS production due to virus infection and its associated hyper host immune response (iii) modulating micro RNAs that regulate the endothelial activation and its integrity by downregulating the inflammatory response during ssRNA infection.

The potential role of ischaemia-reperfusion injury in chronic, relapsing diseases such as rheumatoid arthritis, Long COVID, and ME/CFS: evidence, mechanisms, and therapeutic implications

Ischaemia–reperfusion (I–R) injury, initiated via bursts of reactive oxygen species produced during the reoxygenation phase following hypoxia, is well known in a variety of acute circumstances. We argue here that I–R injury also underpins elements of the pathology of a variety of chronic, inflammatory diseases, including rheumatoid arthritis, ME/CFS and, our chief focus and most proximally, Long COVID. Ischaemia may be initiated via fibrin amyloid microclot blockage of capillaries, for instance as exercise is started; reperfusion is a necessary corollary when it finishes. We rehearse the mechanistic evidence for these occurrences here, in terms of their manifestation as oxidative stress, hyperinflammation, mast cell activation, the production of marker metabolites and related activities. Such microclot-based phenomena can explain both the breathlessness/fatigue and the post-exertional malaise that may be observed in these conditions, as well as many other observables. The recognition of these processes implies, mechanistically, that therapeutic benefit is potentially to be had from antioxidants, from anti-inflammatories, from iron chelators, and via suitable, safe fibrinolytics, and/or anti-clotting agents. We review the considerable existing evidence that is consistent with this, and with the biochemical mechanisms involved.

Anticoagulation Strategies during Extracorporeal Membrane Oxygenation: A Narrative Review

The development of extracorporeal life support technology has added a new dimension to the care of critically ill patients who fail conventional treatment options. Extracorporeal membrane oxygenation (ECMO)—specialized temporary life support for patients with severe cardiac or pulmonary failure—plays a role in bridging the time for organ recovery, transplant, or permanent assistance. The overall patient outcome is dependent on the underlying disease, comorbidities, patient reaction to critical illness, and potential adverse events during ECMO. Moreover, the contact of the blood with the large artificial surface of an extracorporeal system circuit triggers complex inflammatory and coagulation responses. These processes may further lead to endothelial injury and disrupted microcirculation with consequent end-organ dysfunction and the development of adverse events like thromboembolism. Therefore, systemic anticoagulation is considered crucial to alleviate the risk of thrombosis and failure of ECMO circuit components. The gold standard and most used anticoagulant during extracorporeal life support is unfractionated heparin, with all its benefits and disadvantages. However, therapeutic anticoagulation of a critically ill patient carries the risk of clinically relevant bleeding with the potential for permanent injury or death. Similarly, thrombotic events may occur. Therefore, different anticoagulation strategies are employed, while the monitoring and the balance of procoagulant and anticoagulatory factors is of immense importance. This narrative review summarizes the most recent considerations on anticoagulation during ECMO support, with a special focus on anticoagulation monitoring and future directions.

Anemia-Associated Platelets and Plasma Prothrombin Time Increase in Patients with Adenomyosis

Patients with adenomyosis are hypercoagulable and often accompanied by anemia, but the specific changes in anemia-related coagulation parameters are still unclear. This study investigated the changes in and influencing factors of coagulation parameters related to anemia in patients with adenomyosis (AM). The coagulation parameters, including platelet count (PC), plasma prothrombin time (PT), activated partial prothrombin time (APTT), thrombin time (TT) and fibrinogen (FB), and hemoglobin (Hb), were measured in patients with adenomyosis (229 cases in AM group), uterine leiomyoma (265 cases in LM group), and undergoing tubal anastomosis (142 cases in the control group). The age of the control group was younger than that of the AM group and the LM group. Compared with the AM and LM groups, the uterus size of the control group was smaller; the AM group was larger than the LM group. The Hb concentration of the AM group was lower than that of the LM and control groups. Compared with the LM and control groups, PC increased and TT shortened in the AM group. APTT in the AM group was shorter than in the control group, and PT was longer than in the LM group. After adjustment using multiple logistic regression analysis, adenomyosis was correlated with Hb concentration (or = 0.971, 95% CI 0.954−0.988, p < 0.001), PC (or = 1.006, 95% CI 1.002−1.011, p = 0.004), PT (or = 3.878, 95% CI 2.347−6.409, p < 0.001), age (or = 1.062, 95% CI 1.013−1.114, p = 0.013), and uterine size (or = 1.103, 95% CI 1.011−1.203, p = 0.028). Correlation analysis showed that PC (r = −0.309) and PT (r = −0.252) were negatively correlated with anemia. The increase in Hb-related PC and PT in patients with adenomyosis indicates that the timely and early detection of coagulation parameters is needed for patients with severe anemia, older age, and larger uterine volume.

Leukocyte as an Independent Predictor of Lower-Extremity Deep Venous Thrombosis in Elderly Patients With Primary Intracerebral Hemorrhage

Objective

Due to the interaction of leukocytes with platelets and coagulation factors, they may in turn play a role in hemostasis or the formation of thrombi. This study aimed to investigate the association of leukocytosis on admission with an increased risk of acute lower-extremity deep venous thrombosis (LEDVT) in elderly patients with primary intracerebral hemorrhage (ICH).

Methods

This was a single-center, retrospective observational study of consecutive patients observed with spontaneous ICH aged 60 years or above at Lanzhou University Second Hospital from January 2017 to September 2021. Clinical data and demographic information were collected and analyzed. Univariate and multivariate analyses were conducted to identify independent risk factors of acute LEDVT. One-to-one matching was implemented to balance important patient characteristics by the groups' propensity score matching (PSM) analysis.

Results

A total of 371 elderly patients with primary ICH fulfilled requirements for inclusion and exclusion, of whom 33 (8.89%) experienced LEDVT. Leukocyte counts were statistically higher in the LEDVT group compared to the non-LEDVT group [12.89 (8.80–14.61) × 10⁹ cells/L vs. 8.31 (6.60–10.75) × 10⁹ cells /L, p < 0.001]. Multivariate logistic regression models adjusted for several potential confounding factors were performed, and leukocytes were consistently a significant independent predictor of LEDVT. The optimal cut-off value of leukocyte counts calculated from the receiver operating characteristic (ROC) curve to predict LEDVT was 10.22 × 10⁹ cells /L (area under the curve:0.714, 95%CI 0.665–0.759; the sensitivity was 72.73%; the specificity was 71.01%) in elderly patients with primary ICH. After one-to-one PSM, compared to the matched non-LEDVT group, the matched LEDVT group had significantly higher leukocyte counts [11.98 (8.40–13.94) × 10⁹ cells/L vs. 6.12 (4.68–12.00) × 10⁹ cells/L, p = 0.003]. After PSM, the ROC curve was plotted for leukocytes as a predictor of LEDVT, with an AUC of 0.722 (95%CI 0.593–0.828, p = 0.001; the sensitivity was 87.10%, and the specificity was 61.29%). Elevated leukocytes remained independently significant as predictors of LEDVT in elderly patients with primary ICH.

Conclusion

Leukocyte at admission is an independent risk factor of LEDVT in elderly patients with primary ICH.

Effects of Interleukin-17A on the Early Stages of Arterial Thrombosis in Mice

PURPOSE

Interleukin (IL)-17A has been suggested to play a role in the growth and organization of thrombi. We examined whether IL-17A plays a role in the early stages of thrombosis and whether there are sex differences in the effects of IL-17A.

MATERIALS AND METHODS

We performed a blinded, randomized, placebo-controlled study to compare time to thrombotic occlusion and sex differences therein between mice treated with IL-17A and those treated with saline using a ferric chloride-induced model. We also assessed thrombus histology, blood coagulation, and plasma levels of coagulation factors.

RESULTS

Time to occlusion values did not differ between the IL-17A group and the control group (94.6±86.9 sec vs. 121.0±84.4 sec, p=0.238). However, it was significantly shorter in the IL-17A group of female mice (74.6±57.2 sec vs. 130.0±76.2 sec, p=0.032). In rotational thromboelastometry, the IL-17A group exhibited increased maximum clot firmness (71.3±4.5 mm vs. 66.7±4.7 mm, p=0.038) and greater amplitude at 30 min (69.7±5.2 mm vs. 64.5±5.3 mm, p=0.040) than the control group. In Western blotting, the IL-17A group showed higher levels of coagulation factor XIII (2.2±1.5 vs. 1.0±0.9, p=0.008), monocyte chemoattractant protein-1 (1.6±0.6 vs. 1.0±0.4, p=0.023), and tissue factor (1.5±0.6 vs. 1.0±0.5, p=0.003).

CONCLUSION

IL-17A plays a role in the initial st ages of arterial thrombosis in mice. Coagulation factors and monocyte chemoattractant protein-1 may be associated with IL-17A-mediated thrombosis.

Nuclear Progestin Receptor-mediated Linkage of Blood Coagulation and Ovulation

Ovulation is a dramatic remodeling process that includes rupture of blood capillaries and clotting, but coagulation is not thought to directly regulate this process. Herein, we report remarkable increases of coagulation factors V (f5, ~3145-fold) and tissue factor (f3a, ~120-fold) in zebrafish ovarian follicle cells during ovulation. This increase was mediated through the nuclear progestin receptor (Pgr), which is essential for ovulation in zebrafish, and was totally abolished in ovarian follicular cells from pgr-/- mutants. In addition, promoter activities of f5 and f3a were significantly enhanced by progestin (DHP) via Pgr. Similar regulation of human F5 promoter activity was induced via human PGRB, suggesting a conserved mechanism. Site-directed mutagenesis of the zebrafish f5 promoter further demonstrated a direct regulation of coagulation factors via progestin response elements. Moreover, a stark increase of erythrocytes occurred in capillaries meshed in wild-type preovulatory follicles but was absent in pgr-/- mutants. Interestingly, anticoagulants significantly inhibited ovulation both in vitro and in vivo, respectively. Furthermore, reduced fecundity was observed in f5+/- female zebrafish. Taken together, our study provides plausible evidence for steroid regulation of coagulation factors, and a new hypothesis for blood clotting-triggered ovulation in vertebrates.

The risk of thromboembolic events with early intravenous 2- and 4-g bolus dosing of tranexamic acid compared to placebo in patients with severe traumatic bleeding: A secondary analysis of a randomized, double-blind, placebo-controlled, single-center trial

BACKGROUND

Screening for the risk of thromboembolism (TE) due to tranexamic acid (TXA) in patients with severe traumatic injury has not been performed in randomized clinical trials. Our objective was to determine if TXA dose was independently-associated with thromboembolism.

STUDY DESIGN AND METHODS

This is a secondary analysis of a single-center, double-blinded, randomized controlled trial comparing placebo to a 2-g or 4-g intravenous TXA bolus dose in trauma patients with severe injury. We used multivariable discrete-time Cox regression models to identify associations with risk for thromboembolic events within 30 days post-enrollment. Event curves were created using discrete-time Cox regression.

RESULTS

There were 50 patients in the placebo group, 49 in the 2-g, and 50 in the 4-g TXA group. In adjusted analyses for thromboembolism, a 2-g dose of TXA had an hazard ratio (HR, 95% confidence interval [CI]) of 3.20 (1.12-9.11) (p = .029), and a 4-g dose of TXA had an HR (95% CI) of 5.33 (1.94-14.63) (p = .001). Event curves demonstrated a higher probability of thromboembolism for both doses of TXA compared to placebo. Other parameters independently associated with thromboembolism include time from injury to TXA administration, body mass index, and total blood products transfused.

DISCUSSION

In patients with severe traumatic injury, there was a dose-dependent increase in the risk of at least one thromboembolic event with TXA. TXA should not be withheld, but thromboembolism screening should be considered for patients receiving a dose of at least 2-g TXA intravenously for traumatic hemorrhage.

Alboserpin, the Main Salivary Anticoagulant from the Disease Vector Aedes albopictus, Displays Anti-FXa-PAR Signaling In Vitro and In Vivo

Blood-feeding arthropods secrete potent salivary molecules, which include platelet aggregation inhibitors, vasodilators, and anticoagulants. Among these molecules, Alboserpin, the major salivary anticoagulant from the mosquito vector Aedes albopictus, is a specific inhibitor of the human coagulation factor Xa (FXa). In this study, we investigated the anti-inflammatory properties of Alboserpin, in vitro and in vivo. In vitro, Alboserpin inhibited FXa-induced protease-activated receptor (PAR)-1, PAR-2, PAR-3, VCAM, ICAM, and NF-κB gene expression in primary dermal microvascular endothelial cells. Alboserpin also prevented FXa-stimulated ERK1/2 gene expression and subsequent inflammatory cytokine release (MCP-1, TNF-α, IL-6, IL-8, IL-1β, IL-18). In vivo, Alboserpin reduced paw edema induced by FXa and subsequent release of inflammatory cytokines (CCL2, MCP-1, IL-1α, IL-6, IL-1β). Alboserpin also reduced FXa-induced endothelial permeability in vitro and in vivo. These findings show that Alboserpin is a potent anti-inflammatory molecule, in vivo and in vitro, and may play a significant role in blood feeding.

Factor VII, EPCR, aPC Modulators: novel treatment for neuroinflammation

Background

Inflammation and coagulation are linked and pathogenic in neuroinflammatory diseases. Protease-activated receptor 1 (PAR1) can be activated both by thrombin, inducing increased inflammation, and activated protein C (aPC), inducing decreased inflammation. Modulation of the aPC-PAR1 pathway may prevent the neuroinflammation associated with PAR1 over-activation.

Methods

We synthesized a group of novel molecules based on the binding site of FVII/aPC to the endothelial protein C receptor (EPCR). These molecules modulate the FVII/aPC-EPCR pathway and are therefore named FEAMs—Factor VII, EPCR, aPC Modulators. We studied the molecular and behavioral effects of a selected FEAM in neuroinflammation models in-vitro and in-vivo.

Results

In a lipopolysaccharide (LPS) induced in-vitro model, neuroinflammation leads to increased thrombin activity compared to control (2.7 ± 0.11 and 2.23 ± 0.13 mU/ml, respectively, p = 0.01) and decreased aPC activity (0.57 ± 0.01 and 1.00 ± 0.02, respectively, p < 0.0001). In addition, increased phosphorylated extracellular regulated kinase (pERK) (0.99 ± 0.13, 1.39 ± 0.14, control and LPS, p < 0.04) and protein kinase B (pAKT) (1.00 ± 0.09, 2.83 ± 0.81, control and LPS, p < 0.0002) levels indicate PAR1 overactivation, which leads to increased tumor necrosis factor-alpha (TNF-α) level (1.00 ± 0.04, 1.35 ± 0.12, control and LPS, p = 0.02). In a minimal traumatic brain injury (mTBI) induced neuroinflammation in-vivo model in mice, increased thrombin activity, PAR1 activation, and TNF-α levels were measured. Additionally, significant memory impairment, as indicated by a lower recognition index in the Novel Object Recognition (NOR) test and Y-maze test (NOR: 0.19 ± 0.06, -0.07 ± 0.09, p = 0.03. Y-Maze: 0.50 ± 0.03, 0.23 ± 0.09, p = 0.02 control and mTBI, respectively), as well as hypersensitivity by hot-plate latency (16.6 ± 0.89, 12.8 ± 0.56 s, control and mTBI, p = 0.01), were seen. FEAM prevented most of the molecular and behavioral negative effects of neuroinflammation in-vitro and in-vivo, most likely through EPCR-PAR1 interactions.

Conclusion

FEAM is a promising tool to study neuroinflammation and a potential treatment for a variety of neuroinflammatory diseases.

Soluble mannose receptor CD206 and von Willebrand factor are early biomarkers to identify patients at risk for severe or necrotizing acute pancreatitis

Background

In acute pancreatitis (AP), microcirculatory dysfunction and leukocyte activation contribute to organ damage, inflammation, and mortality. Given the role of macrophage activation, monocyte recruitment, and microthrombus formation in the early pathogenesis of AP, we examined the macrophage activation marker soluble mannose receptor (sCD206) and the endothelial function marker von Willebrand factor (vWF) in patients admitted for AP.

Methods

In an exploratory analysis, serum sCD206 and plasma vWF were prospectively analyzed on day 1 and day 3 in 81 patients with AP admitted to the hospital. In addition, blood samples from 59 patients with early AP admitted to the intensive care unit and symptom onset < 24 h were retrospectively analyzed. Patients were dichotomized as per study protocol into two groups: (i) “non-severe edematous AP” including patients with mild AP without organ failure and patients with transient organ failure that resolves within 48 h and (ii) “severe/necrotizing AP” including patients with severe AP and persistent organ failure > 48 h and/or patients with local complications.

Results

In the prospective cohort, 17% developed severe/necrotizing pancreatitis compared with 56% in the ICU cohort. Serum concentrations of sCD206 on admission were higher in patients with severe/necrotizing AP than in patients with non-severe edematous AP (prospective: 1.57 vs. 0.66 mg/l, P = 0.005; ICU: 1.76 vs. 1.25 mg/l, P = 0.006), whereas other inflammatory markers (leukocytes, C-reactive protein, procalcitonin) and disease severity (SOFA, SAPS II, APACHE II) did not show significant differences. Patients with severe/necrotizing AP had a greater increase in sCD206 than patients with non-severe edematous AP at day 3 in the prospective cohort. In contrast to routine coagulation parameters, vWF antigen levels were elevated on admission (prospective cohort: 375 vs. 257%, P = 0.02; ICU cohort: 240 vs. 184%, P = 0.03). When used as continuous variables, sCD206 and VWF antigen remained predictors of severe/necrotizing AP after adjustment for etiology and age in both cohorts.

Conclusions

sCD206 identifies patients at risk of severe AP at earlier timepoints than routine markers of inflammation and coagulation. Prospective studies are needed to investigate whether incorporating early or repeated measurements into the existing scoring system will better identify patients at increased risk for complications of AP.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40560-022-00619-2.

Soil-Transmitted Helminths and Anaemia: A Neglected Association Outside the Tropics

Anaemia is an important cause of morbidity and mortality globally. Among infectious agents responsible for anaemia, helminthic infections are often neglected, particularly in non-endemic countries. However, they should not be neglected in this setting, as international travel and migration are on the rise. In this narrative review, we aimed to describe soil-transmitted helminths as a cause of or contributing factor to anaemia, focusing on hookworms (Necator americanus and Ancylostoma duodenale), the whipworm (Trichuris trichiura), the roundworm (Ascaris lumbricoides), and the threadworm (Strongyloides stercoralis). A general review on the epidemiology, lifecycle, and clinical spectrum of anaemia is proposed, with a special focus on helminthic infections’ association with anaemia as well as the diagnostic approach, which are both particularly important in non-endemic settings.

Associations between inflammation, coagulation, cardiac strain and injury, and subclinical vascular disease with frailty in older men: a cross-sectional study

BACKGROUND

Inflammation, coagulation activation, endothelial dysfunction and subclinical vascular disease are cross-sectionally associated with frailty. Cardiac-specific biomarkers are less-well characterised. We assessed associations between these and frailty, in men with, and without, cardiovascular disease (CVD).

METHODS

Cross-sectional analysis of 1096 men without, and 303 with, CVD, aged 71-92, from the British Regional Heart Study. Multinominal logistic regression was performed to examine the associations between frailty status (robust/pre-frail/frail) and, separately, C-reactive protein (CRP), interleukin-6 (IL-6), tissue plasminogen activator (tPA), D-dimer, von Willebrand factor (vWF), high-sensitivity cardiac troponin-T (hs-cTnT), N-terminal pro B-type natriuretic peptide (NT-proBNP) (all natural log-transformed), and, in men without CVD, carotid intima-media thickness (CIMT), carotid-femoral pulse wave velocity (cfPWV), carotid distensibility coefficient (DC), and ankle-brachial pressure index (ABPI), adjusted for age, renal function, BMI, social class, smoking, polypharmacy, cognition, multimorbidity and systolic blood pressure. Explanatory variables with p < 0.05 were carried forward into mutually-adjusted analysis.

RESULTS

In men without CVD, higher CRP, IL-6, vWF, tPA, hs-cTnT, NT-proBNP, cfPWV, and lower DC were significantly associated with frailty; mutually-adjusted, log IL-6 (OR for frailty = 2.02, 95%CI 1.38-2.95), log hs-cTnT (OR = 1.95, 95%CI 1.24-3.05) and DC (OR = 0.92, 95%CI 0.86-0.99) retained associations. In men with CVD, higher CRP, IL-6, and hs-cTnT, but not vWF, tPA, NT-proBNP or D-dimer, were significantly associated with frailty; mutually-adjusted, log hs-cTnT (OR 3.82, 95%CI 1.84-7.95) retained a significant association.

CONCLUSIONS

In older men, biomarkers of myocardial injury are associated with frailty. Inflammation is associated with frailty in men without CVD. Carotid artery stiffness is associated with frailty in men without CVD, independently of these biomarkers.

The Role of Excessive Anticoagulation and Missing Hyperinflammation in ECMO-Associated Bleeding

Extracorporeal membrane oxygenation (ECMO) is increasingly used in carefully selected patients with cardiac or respiratory failure. However, complications are common and can be associated with worse outcomes, while data on risk factors and outcomes are inconsistent and sparse. Therefore, we sought to investigate potential risk factors and predictors of haemorrhage and adverse events during ECMO and its influence on mortality. We retrospectively reviewed all patients on ECMO support admitted to intensive care units of a tertiary university centre in Austria. In a period of ten years, ECMO support was used in 613 patients, with 321 patients meeting the inclusion criteria of this study. Haemorrhage, occurring in more than one third of the included patients (123, 38%), represented the most common and serious ECMO complication, being associated with an increased one year mortality (51% vs. 35%, p = 0.005). The main risk factors for haemorrhage were severity of the disease (hazard ratio (HR) = 1.01, p = 0.047), a prolonged activated partial thromboplastin time (HR = 1.01, p = 0.007), and lower values of C-reactive protein (HR = 0.96, p = 0.005) and procalcitonin (HR = 0.99, p = 0.029). In summary, haemorrhage remained the main ECMO complication with increased mortality. Moreover, we reported a possible association of lower inflammation and bleeding during ECMO support for the first time. This generated a new hypothesis that warrants further research. Finally, we recommend stricter monitoring of anticoagulation especially in patients without hyperinflammation.

Suppression of fibrin(ogen)-driven pathologies in disease models through controlled knockdown by lipid nanoparticle delivery of siRNA

Fibrinogen plays a pathologic role in multiple diseases. It contributes to thrombosis and modifies inflammatory and immune responses, supported by studies in mice expressing fibrinogen variants with altered function or with a germline fibrinogen deficiency. However, therapeutic strategies to safely and effectively tailor plasma fibrinogen concentration are lacking. Here, we developed a strategy to tune fibrinogen expression by administering lipid nanoparticle (LNP)-encapsulated small interfering RNA (siRNA) targeting the fibrinogen α chain (siFga). Three distinct LNP-siFga reagents reduced both hepatic Fga messenger RNA and fibrinogen levels in platelets and plasma, with plasma levels decreased to 42%, 16%, and 4% of normal within 1 week of administration. Using the most potent siFga, circulating fibrinogen was controllably decreased to 32%, 14%, and 5% of baseline with 0.5, 1.0, and 2.0 mg/kg doses, respectively. Whole blood from mice treated with siFga formed clots with significantly decreased clot strength ex vivo, but siFga treatment did not compromise hemostasis following saphenous vein puncture or tail transection. In an endotoxemia model, siFga suppressed the acute phase response and decreased plasma fibrinogen, D-dimer, and proinflammatory cytokine levels. In a sterile peritonitis model, siFga restored normal macrophage migration in plasminogen-deficient mice. Finally, treatment of mice with siFga decreased the metastatic potential of tumor cells in a manner comparable to that observed in fibrinogen-deficient mice. The results indicate that siFga causes robust and controllable depletion of fibrinogen and provides the proof-of-concept that this strategy can modulate the pleiotropic effects of fibrinogen in relevant disease models.

Using a Systems Approach to Explore the Mechanisms of Interaction Between Severe Covid-19 and Its Coronary Heart Disease Complications

Frontiers requested research on how a systems approach can explore the mechanisms of cardiovascular complications in Covid-19. The focus of this paper will thus be on these detailed mechanisms. It will elucidate the integrated pathogenic pathways based on an extensive review of literature. Many severe Covid-19 cases and deaths occur in patients with chronic cardiovascular comorbidities. To help understand all the mechanisms of this interaction, Covid-19 complications were integrated into a pre-existing systems-based coronary heart disease (CHD) model. Such a complete model could not be found in literature. A fully integrative view could be valuable in identifying new pharmaceutical interventions, help understand how health factors influence Covid-19 severity and give a fully integrated explanation for the Covid-19 death spiral phenomenon seen in some patients. Covid-19 data showed that CHD hallmarks namely, Hypercoagulability, Hypercholesterolemia, Hyperglycemia/Hyperinsulinemia, Inflammation and Hypertension have an important effect on disease severity. The pathogenic pathways that Covid-19 activate in CHD were integrated into the CHD model. This fully integrated model presents a visual explanation of the mechanism of interaction between CHD and Covid-19 complications. This includes a detailed integrated explanation of the death spiral as a result of interactions between Inflammation, endothelial cell injury, Hypercoagulability and hypoxia. Additionally, the model presents the aggravation of this death spiral through the other CHD hallmarks namely, Hyperglycemia/Hyperinsulinemia, Hypercholesterolemia, and/or Hypertension. The resulting model further suggests systematically how the pathogenesis of nine health factors (stress, exercise, smoking, etc.) and seven pharmaceutical interventions (statins, salicylates, thrombin inhibitors, etc.) may either aggravate or suppress Covid-19 severity. A strong association between CHD and Covid-19 for all the investigated health factors and pharmaceutical interventions, except for β-blockers, was found. It is further discussed how the proposed model can be extended in future to do computational analysis to help assess the risk of Covid-19 in cardiovascular disease. With insight gained from this study, recommendations are made for future research in potential new pharmacotherapeutics. These recommendations could also be beneficial for cardiovascular disease, which killed five times more people in the past year than Covid-19.

Frequency and risk factors for thrombosis in acute myeloid leukemia and high-risk myelodysplastic syndromes treated with intensive chemotherapy: a two centers observational study

The frequency of thrombosis in AML has been evaluated only in a few studies and no validated predictive model is currently available. Recently, DIC score was shown to identify patients at higher thrombotic risk. We aimed to evaluate the frequency of thromboembolism in AML patients treated with intensive chemotherapy and to assess the ability of genetic and clinical factors to predict the thrombotic risk. We performed a retrospective observational study including 222 newly diagnosed adult AML (210) and high-risk MDS (12), treated with intensive chemotherapy between January 2013 and February 2020. With a median follow-up of 44 months, we observed 50 thrombotic events (90% were venous, VTE). The prevalence of thrombosis was 22.1% and the 6-months cumulative incidence of thrombosis was 10%. The median time to thrombosis was 84 days and 52% of the events occurred within 100 days from AML diagnosis. Khorana and DIC score failed to stratify patients according to their thrombotic risk. Only history of a thrombotic event (p = 0.043), particularly VTE (p = 0.0053), platelet count above 100 × 10⁹/L at diagnosis (p = 0.036) and active smoking (p = 0.025) significantly and independently increased the risk of thrombosis, the latter particularly of arterial events. AML genetic profile did not affect thrombosis occurrence. Results were confirmed considering only thromboses occurring within day 100 from diagnosis. DIC score at diagnosis, but not thrombosis, was independently associated with reduced survival (p = 0.004). Previous VTE, platelet count above 100 × 10⁹/L and active smoking were the only factors associate with increased thrombotic risk in AML patients treated intensively, but further studies are needed to validate these results.

Innate immunity: the first line of defense against SARS-CoV-2

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus (SARS-CoV)-2, continues to cause substantial morbidity and mortality. While most infections are mild, some patients experience severe and potentially fatal systemic inflammation, tissue damage, cytokine storm and acute respiratory distress syndrome. The innate immune system acts as the first line of defense, sensing the virus through pattern recognition receptors and activating inflammatory pathways that promote viral clearance. Here, we discuss innate immune processes involved in SARS-CoV-2 recognition and the resultant inflammation. Improved understanding of how the innate immune system detects and responds to SARS-CoV-2 will help identify targeted therapeutic modalities that mitigate severe disease and improve patient outcomes.

Interconnections between Inflammageing and Immunosenescence during Ageing

Acute inflammation is a physiological response to injury or infection, with a cascade of steps that ultimately lead to the recruitment of immune cells to clear invading pathogens and heal wounds. However, chronic inflammation arising from the continued presence of the initial trigger, or the dysfunction of signalling and/or effector pathways, is harmful to health. While successful ageing in older adults, including centenarians, is associated with low levels of inflammation, elevated inflammation increases the risk of poor health and death. Hence inflammation has been described as one of seven pillars of ageing. Age-associated sterile, chronic, and low-grade inflammation is commonly termed inflammageing-it is not simply a consequence of increasing chronological age, but is also a marker of biological ageing, multimorbidity, and mortality risk. While inflammageing was initially thought to be caused by "continuous antigenic load and stress", reports from the last two decades describe a much more complex phenomenon also involving cellular senescence and the ageing of the immune system. In this review, we explore some of the main sources and consequences of inflammageing in the context of immunosenescence and highlight potential interventions. In particular, we assess the contribution of cellular senescence to age-associated inflammation, identify patterns of pro- and anti-inflammatory markers characteristic of inflammageing, describe alterations in the ageing immune system that lead to elevated inflammation, and finally assess the ways that diet, exercise, and pharmacological interventions can reduce inflammageing and thus, improve later life health.

Inflammation and necrosis syndrome is associated with alterations in blood and metabolism in pigs

Background

Swine inflammation and necrosis syndrome (SINS) can lead to significant clinical alterations at tail, ears, claws and other parts of the body in suckling piglets, weaners and fatteners. Clinical findings are associated with vasculitis, intima proliferation and thrombosis. The syndrome can be found in newborns, indicating a primarily endogenous aetiology. It has been hypothesized that SINS is triggered by gut-derived microbial-associated molecular patterns, causing derangements in liver metabolism and activity of peripheral white blood cells involving inflammation and blood haemostasis. In order to characterize these metabolic derangements of SINS for the first time, red and white blood counts, parameters of blood haemostasis, serum metabolites and acute phase proteins in the serum were analysed in 360 piglets, weaners and fatteners, each with significantly different SINS scores.

Results

SINS scores and haematological/clinical chemical parameters were significantly associated (P < 0.05), especially in weaners and fatteners. Higher degrees of clinical SINS were associated with increased numbers of monocytes and neutrophils. Blood coagulation was altered in weaners and a thrombocytopenia was found in fatteners. Additionally, acute phase proteins, especially C-reactive protein and fibrinogen were increased in serum. Serum metabolites and serum liver enzymes were slightly altered. Aspartate transaminase levels overall exceeded physiological limit and increased in parallel with SINS scores in fatteners.

Conclusion

Clinical inflammation and necrosis at tail, ears, claws and other parts of the body were significantly associated with haematology and serum clinical chemistry, especially in weaners and fatteners. The involvement of inflammatory cells, blood coagulation, acute phase proteins and certain serum metabolites support the inflammatory-necrotising character of the syndrome and provide starting points for further studies to decipher its exact pathogenesis. The low to moderate variations seem less suitable for diagnostic use.

Identification of Molecular Subgroups in Liver Cirrhosis by Gene Expression Profiles

Background: Liver cirrhosis is characterized by high mortality, bringing a serious health and economic burden to the world. The clinical manifestations of liver cirrhosis are complex and heterogeneous. According to subgroup characteristics, identifying cirrhosis has become a challenge. Objectives: The purpose of this study was to evaluate the difference between different subgroups of cirrhosis. The ultimate goal of research on these different phenotypes was to discover groups of patients with unique treatment characteristics, and formulate targeted treatment plans that improve the prognosis of the disease and improve the patients’ quality of life. Methods: We obtained the relevant gene chip by searching the gene expression omnibus (GEO) database. According to the gene expression profile, 79 patients with liver cirrhosis were divided into four subgroups, which showed different expression patterns. Therefore, we used weighted gene coexpression network analysis (WGCNA) to find differences between subgroups. Results: The characteristics of the WGCNA module indicated that subjects in subgroup I might exhibit inflammatory characteristics; subjects in subgroup II might exhibit metabolically active characteristics; arrhythmogenic right ventricular cardiomyopathy and neuroactive ligand-receptive somatic interaction pathways were significantly enriched in subgroup IV. We did not find a significantly upregulated pathway in the third subgroup. Conclusions: In this study, a new type of clinical phenotype classification of liver cirrhosis was derived by consensus clustering. This study found that patients in different subgroups may have unique gene expression patterns. This new classification method helps researchers explore new treatment strategies for cirrhosis based on clinical phenotypic characteristics.

Proteomic and metabolomic profiling of urine uncovers immune responses in patients with COVID-19

The utility of the urinary proteome in infectious diseases remains unclear. Here, we analyzed the proteome and metabolome of urine and serum samples from patients with COVID-19 and healthy controls. Our data show that urinary proteins effectively classify COVID-19 by severity. We detect 197 cytokines and their receptors in urine, but only 124 in serum using TMT-based proteomics. The decrease in urinary ESCRT complex proteins correlates with active SARS-CoV-2 replication. The downregulation of urinary CXCL14 in severe COVID-19 cases positively correlates with blood lymphocyte counts. Integrative multiomics analysis suggests that innate immune activation and inflammation triggered renal injuries in patients with COVID-19. COVID-19-associated modulation of the urinary proteome offers unique insights into the pathogenesis of this disease. This study demonstrates the added value of including the urinary proteome in a suite of multiomics analytes in evaluating the immune pathobiology and clinical course of COVID-19 and, potentially, other infectious diseases.

Prognostic significance of international normalised ratio and prothrombin time in Chinese acute ischaemic stroke patients

BACKGROUND

We investigated the association between international normalised ratio (INR) and prothrombin time (PT) levels on hospital admission and in-hospital outcomes in acute ischaemic stroke (AIS) patients.

METHODS

A total of 3175 AIS patients enrolled from December 2013 to May 2014 across 22 hospitals in Suzhou city were included. We divided patients into four groups according to their level of admission INR: (<0.92), Q2 (0.92-0.98), Q3 (0.98-1.04) and Q4 (≥1.04) and PT. Logistic regression models were used to estimate the effect of INR and PT on death or major disability (modified Rankin Scale score (mRS)>3), death and major disability (mRS scores 4-5) separately on discharge in AIS patients.

RESULTS

Having an INR level in the highest quartile (Q4) was associated with an increased risk of death or major disability (OR 1.69; 95% CI 1.23 to 2.31; P-trend=0.001), death (OR, 2.64; 95% CI 1.12 to 6.19; P-trend=0.002) and major disability on discharge (OR, 1.56; 95% CI 1.13 to 2.15; P-trend=0.008) in comparison to Q1 after adjusting for potential covariates. Moreover, in multivariable logistic regression models, having a PT level in the highest quartile also significantly increased the risk of death (OR, 2.38; 95% CI 1.06 to 5.32; P-trend=0.006) but not death or major disability (P-trend=0.240), major disability (P-trend=0.606) on discharge.

CONCLUSIONS

High INR at admission was independently associated with death or major disability, death and major disability at hospital discharge in AIS patients and increased PT was also associated with death at hospital discharge.

Analysis of Prognostic Risk Factors of Sepsis Patients in Intensive Care Unit Based on Data Analysis

In this paper, a data-enabled analysis of the prognostic risk factors of sepsis patients in the intensive care unit is presented. For this purpose, we have selected 220 sepsis patients, preferably those admitted to the intensive care unit for treatment in a tertiary a hospital in Tianjin from June 2018 to June 2019 and received complete data as the research objects, to explore the prognostic risk factors of sepsis patients in the intensive care unit. All patients met the SSC sepsis diagnosis guidelines and recorded the patients' age, gender, underlying disease, and infection site. Laboratory indicators, such as blood routine, electrolytes, arterial blood gas, liver function, and renal function, were collected within 24 hours of admission. Furthermore, the corresponding specimens were cultured for pathogenic microorganisms according to the site of infection. The LAC value was measured at admission and 24 h after admission, and the 24 h lactate clearance rate was calculated. The Acute Physiological and Chronic Health Status Score II (APACHE-II) and SOFA score were calculated, which were based on the worst value of the index within 24 hours after admission. According to the prognosis of patients during hospitalization, they are divided into two groups: (i) survival group and (ii) death group. We entered all the data into Excel and used SPSS21.0 statistical software for data analysis and processing. Quantitative data are tested for normality. Quantitative data for normal distribution are expressed as mean ± standard deviation, and normal distribution and uniform variance are measured. The factors affecting the prognosis of patients with sepsis were first subjected to a single-factor logistic regression analysis, and a multiple logistic regression analysis was performed on the basis of the significance of the single-factor analysis. The results found that the prognosis of patients with sepsis in the ICU is affected by multiple factors such as underlying diseases, infectious microorganisms, comorbidities, and interventional therapy. APACHE-II score, 24 h lactate clearance rate, ARDS, and DIC are independent risk factors that affect the prognosis of ICU patients.

Thrombin cleaves IL-33 and modulates IL-33-activated allergic lung inflammation

BACKGROUND

Organisms have orchestrated coagulation and immune systems. Although a link between inflammation and haemostasis has been reported in asthma, the interaction mechanism has not been completely elucidated. Here, we investigated the direct link between the mammalian immune and coagulation systems.

METHODS

Mice were administered protease or antigens intranasally to induce airway inflammation with or without thrombin inhibitors treatment. The effects of thrombin and its inhibitors on interleukin (IL)-33 were investigated both in vivo and in vitro. Peripheral blood mononuclear cells (PBMCs) and plasma from asthma patients are collected to verify the correlation between thrombin and group 2 innate lymphocytes (ILC2s).

RESULTS

Low-molecular-weight heparin (LMWH, an indirect inhibitor of thrombin) restrained both papain- and fungus-induced type 2 immune responses in mice by inhibiting IL-33 cleavage. Upon examining the potential thrombin protease consensus sites, we found that IL-33 was directly cleaved by thrombin at specific amino acids (R48 and R106) to generate a mature form of IL-33 with potent biological activity. In addition, we found that bivalirudin TFA (a direct inhibitor of thrombin) inhibited a variety of type 2 inflammatory responses, such as those in house dust mite (HDM)- and ovalbumin (OVA)-mediated pulmonary inflammation models. We found that plasma thrombin-antithrombin complex (TATc) levels in asthma patients were positively associated with the number and function of IL-33-responder group 2 innate lymphocytes (ILC2s) among peripheral blood mononuclear cells (PBMCs) from asthma patients.

CONCLUSION

The data suggested that thrombin inhibitors administration could be effective in treating lung inflammation by regulating ILC2s via IL-33 maturation, indicating that targeting thrombin is a potential way to treat allergic diseases.

Outcomes of Anticoagulant Therapy with Low-Molecular-Weight Heparin (LMWH) and Warfarin for Thromboangiitis Obliterans (TAO)

BACKGROUND

Thromboangiitis obliterans (TAO) is a chronic, non-atherosclerotic, progressive inflammatory vascular disease affecting the small- and medium-size arteries and veins of the extremities.

OBJECTIVE

To evaluate whether long-term anticoagulation with low-molecular-weight heparin (LMWH) and warfarin is beneficial for treating the inflammation and symptoms associated with TAO.

METHODS

Patients with TAO who underwent anticoagulation as the mainstay of treatment were included in this prospective study. Rest pain relief and healing of trophic lesions (as the primary and secondary endpoint) were investigated at Day 14 and after 6 months of follow-up. High sensitivity C-reactive protein (hsCRP), monocyte count, and ankle-brachial index (ABI) were recorded, and the difference was compared before and after 2-week anticoagulation. The Chi-square test was used to compare the difference between anticoagulant and aspirin groups (based on the literature).

RESULTS

From 2014 to 2019, 18 patients were included. Only 1 patient with wet gangrene received endo-therapy for a failing stent at the start of treatment. After ~14 days, 12 of 13 (92%) patients showed complete ulcer healing, and 17 of 18 (94%) patients showed complete relief from rest pain. Monocyte-counts and hsCRP levels decreased significantly (p<0.001) after a 2-week period of anticoagulation with LMWH. The mean follow-up was 2.6 years (range 0.5-5 years). At 6 months, all patients showed relief of rest pain and complete healing of trophic lesions. All endpoints were significantly improved compared with the aspirin group (p<0.01), and no rest pain or ulcer/gangrene recurred during follow-up.

CONCLUSION

Anticoagulant therapy may alleviate the inflammation and symptoms of TAO.

Venous Thromboembolic Complications in Pediatric Gastrointestinal Diseases: Inflammatory Bowel Disease and Intestinal Failure

In children with gastrointestinal disorders such as inflammatory bowel disease (IBD) and intestinal failure (IF), the risk of venous thromboembolism (VTE) is increased. VTE may lead to pulmonary embolism, sepsis and central line infection, stroke and post-thrombotic syndrome. The purpose of this review is to summarize current knowledge and recent advances around VTE management in pediatric gastroenterology with a focus on IBD and IF. The VTE incidence in children with IBD is reported to be around 4-30 per 10,000 patient-years, with higher incidences for hospitalized children. While in general, IF is less common than IBD, the VTE incidence in children with IF is around 750 per 10,000 patient-years. The most common risk factors for development of VTE involve deviations leading to Virchow's triad (endothelial damage, stasis, and hypercoagulability) and include active inflammation, particularly with colonic involvement, presence of a central venous catheter, underlying thrombophilia, reduced mobility, surgery, and hospitalization. Classes of anticoagulants used for treatment of VTE are low molecular weight heparins and vitamin K antagonists. However, the use of direct oral anticoagulants for treatment or prevention of VTE has not been studied in this pediatric population yet. Pediatric gastroenterologists apply different VTE prevention and treatment strategies due to lack of literature and lack of consensus. We discuss the role of primary and secondary prophylactic use of anticoagulants, and provide tools and recommendations for screening, prevention and management for the specific pediatric populations.