Molecular Detection of Venous Thrombosis in Mouse Models Using SPECT/CT

Disseminated intravascular coagulation: cause, molecular mechanism, diagnosis, and therapy

Disseminated intravascular coagulation (DIC) is a complex and serious condition characterized by widespread activation of the coagulation cascade, resulting in both thrombosis and bleeding. This review aims to provide a comprehensive overview of DIC, emphasizing its clinical significance and the need for improved management strategies. We explore the primary causes of DIC, including sepsis, trauma, malignancies, and obstetric complications, which trigger an overactive coagulation response. At the molecular level, DIC is marked by excessive thrombin generation, leading to platelet and fibrinogen activation while simultaneously depleting clotting factors, creating a paradoxical bleeding tendency. Diagnosing DIC is challenging and relies on a combination of existing diagnostic criteria and laboratory tests. Treatment strategies focus on addressing the underlying causes and may involve supportive care, anticoagulation therapy, and other supportive measures. Recent advances in understanding the pathophysiology of DIC are paving the way for more targeted therapeutic approaches. This review highlights the critical need for ongoing research to enhance diagnostic accuracy and treatment efficacy, ultimately improving patient outcomes in those affected by DIC.

Sonothrombolysis Using Microfluidically Produced Microbubbles in a Murine Model of Deep Vein Thrombosis

The need for safe and effective methods to manage deep vein thrombosis (DVT), given the risks associated with anticoagulants and thrombolytic agents, motivated research into innovative approaches to resolve blood clots. In response to this challenge, sonothrombolysis is being explored as a technique that combines microbubbles, ultrasound, and thrombolytic agents to facilitate the aggressive dissolution of thrombi. Prior studies have indicated that relatively large microbubbles accelerate the dissolution process, either in an in vitro or an arterial model. However, sonothrombolysis using large microbubbles must be evaluated in venous thromboembolism diseases, where blood flow velocity is not comparable. In this study, the efficacy of sonothrombolysis was validated in a murine model of pre-existing DVT. During therapy, microfluidically produced microbubbles of 18 μm diameter and recombinant tissue plasminogen activator (rt-PA) were administered through a tail vein catheter for 30 min, while ultrasound was applied to the abdominal region of the mice. Three-dimensional ultrasound scans were performed before and after therapy for quantification. The residual volume of the thrombi was 20% in animals post sonothrombolysis versus 52% without therapy ( p = 0.012 < 0.05 ), indicating a significant reduction in DVT volume. Histological analysis of tissue sections confirmed a reduction in DVT volume post-therapy. Therefore, large microbubbles generated from a microfluidic device show promise in ultrasound-assisted therapy to address concerns related to venous thromboembolism.

Neutrophil extracellular traps formation may be involved in the association of propranolol with the development of portal vein thrombosis

BACKGROUND & AIMS

Nonselective β blockers (NSBBs) facilitate the development of portal vein thrombosis (PVT) in liver cirrhosis. Considering the potential effect of NSBBs on neutrophils and neutrophil extracellular traps (NETs), we speculated that NSBBs might promote the development of PVT by stimulating neutrophils to release NETs.

MATERIALS AND METHODS

Serum NETs biomarkers were measured, use of NSBBs was recorded, and PVT was evaluated in cirrhotic patients. Carbon tetrachloride and ferric chloride (FeCl3) were used to induce liver fibrosis and PVT in mice, respectively. After treatment with propranolol and DNase I, neutrophils in peripheral blood, colocalization and expression of NETs in PVT specimens, and NETs biomarkers in serum were measured. Ex vivo clots lysis analysis was performed and portal vein velocity and coagulation parameters were tested.

RESULTS

Serum MPO-DNA level was significantly higher in cirrhotic patients treated with NSBBs, and serum H3Cit and MPO-DNA levels were significantly higher in those with PVT. In fibrotic mice, following treatment with propranolol, DNase I significantly shortened the time of FeCl3-induced PVT formation, lowered the peripheral blood neutrophils labelled by CD11b/Ly6G, inhibited the positive staining of H3Cit and the expression of H3Cit and MPO proteins in PVT tissues, and reduced serum nucleosome level. Furthermore, the addition of DNase I to tissue plasminogen activator (tPA) significantly accelerated clots lysis as compared with tPA alone. Propranolol reduced portal vein velocity in fibrotic mice, but did not influence coagulation parameters.

CONCLUSION

Our study provides a clue to the potential impact of NETs formation on the association of NSBBs with the development of PVT.

A Nonbactericidal Anionic Antimicrobial Peptide Provides Prophylactic and Therapeutic Efficacies against Bacterial Infections in Mice by Immunomodulatory-Antithrombotic Duality

Although bactericidal cationic antimicrobial peptides (AMPs) have been well characterized, less information is available about the antibacterial properties and mechanisms of action of nonbactericidal AMPs, especially nonbactericidal anionic AMPs. Herein, a novel anionic antimicrobial peptide (Gy-CATH) with a net charge of -4 was identified from the skin of the frog Glyphoglossus yunnanensis. Gy-CATH lacks direct antibacterial effects but exhibits significantly preventive and therapeutic capacities in mice that are infected with Staphylococcus aureus, Enterobacteriaceae coli, methicillin-resistant Staphylococcus aureus (MRSA), or carbapenem-resistant E. coli (CREC). In vitro and in vivo investigations proved the regulation of Gy-CATH on neutrophils and macrophages involved in the host immune defense against infection. Moreover, Gy-CATH significantly reduced the extent of pulmonary fibrin deposition and prevented thrombosis in mice, which was attributed to the regulatory role of Gy-CATH in physiological anticoagulants and platelet aggregation. These findings show that Gy-CATH is a potential candidate for the treatment of bacterial infection.

Precision Navigation of Venous Thrombosis Guided by Viscosity-Activatable Near-Infrared Fluorescence

Thrombus are blood clots formed by abnormal hemostasis in blood vessels and are closely associated with various diseases such as pulmonary embolism, myocardial infarction and stroke. Early diagnosis and treatment of thrombus is the key to reducing the high risk of thrombotic disease. Given that early thrombus is small in early size, free instability, wide regional distribution and fast formation, it is urgent to develop all-inclusive detection methods that combine high signal-to-noise ratio, in situ dynamic and rapid in-depth tissue imaging. Near-infrared (NIR) fluorescence imaging, with its excellent high spatiotemporal resolution and tissue penetration depth, is a powerful technique for direct visualization of thrombotic events in situ. Considering the fibrin highly expressed in the thrombus is a typical thrombotic target. Moreover, the viscosity of the thrombus is markedly higher than its surroundings. Therefore, we developed a fibrin-targeting and viscosity-activating thrombus NIR fluorescent probe (TIR-V) for high-resolution and high-sensitivity in situ lighten-up thrombus. TIR-V has the advantages of good thrombus targeting, significant "off-on" fluorescence specific response to viscosity, bright NIR fluorescence and good biocompatibility. The thrombus is clearly delineated by a high signal-to-noise ratio NIR fluorescence imaging, enabling imaging detection and precise navigation of thrombotic regions. This work demonstrates the potential of TIR-V as a bifunctional probe for definitive diagnostic imaging and direct navigation of thrombotic lesions in clinical applications.