Search Results (157)

The plasminogen activator system (PAS), comprising urokinase-type plasminogen activator (uPA), tissue-type plasminogen activator (tPA), their receptors, and endogenous inhibitors, has been extensively investigated for its established roles in haemostasis, fibrinolysis, vascular remodelling and extracellular matrix (ECM) homeostasis. Increasing evidence indicates that the functions of the PAS extend well beyond the cardiovascular system and have important regulatory roles in neuronal plasticity, synaptic remodelling, neuroinflammation, and neurotrophic signalling. These processes are increasingly recognized as central contributors to the neurobiological adaptations underlying substance use disorders (SUDs). In this narrative review, we critically evaluate the current evidence regarding the involvement of the PAS in SUDs, with particular emphasis on the molecular and cellular mechanisms through which uPA and tPA influence addiction-related neuroplasticity. The available literature is predominantly derived from preclinical studies, while direct clinical evidence remains limited. Experimental findings support roles for uPA and tPA in modulating reward-related circuitry, behavioural sensitization, relapse-like behaviours, and neurotrophic signalling, including potential interactions with brain-derived neurotrophic factor (BDNF)-related pathways, although the relative contributions of plasmin-dependent and plasmin-independent pathways remain incompletely understood. We also discuss the potential involvement of the PAS in neuroinflammatory responses and synaptic remodelling, together with the challenges associated with translating these findings into clinically relevant biomarkers or therapeutic strategies. Finally, we identify important gaps in current knowledge, including the need for independent replication, mechanistic clarification, and well-designed human studies to establish the clinical relevance of PAS dysregulation in addiction. Collectively, the available evidence supports a modulatory role for the PAS in addiction-related neurobiology and provides a rationale for further translational investigation, while highlighting that PAS-directed therapeutic approaches remain experimental and require substantial preclinical and clinical validation. Full article

Background: Colorectal cancer (CRC) is a major clinical challenge due to high metastasis and therapy resistance. Photodynamic therapy (PDT) offers precise tumor ablation but lacks sustained anti-metastatic activity. Peptidic urokinase-type plasminogen activator (uPA) inhibitors suppress metastasis but suffer from short half-life and poor tumor retention. This study aimed to develop a dual-functional self-assembled nanoplatform integrating PDT and selective uPA inhibition for synergistic CRC treatment. Methods: We designed and synthesized a conjugate by linking pyropheophorbide-a (PPA) with uPA-targeted cyclic peptide IG2, which self-assembled into nanoparticles (PINPs). Physicochemical properties, reactive oxygen species (ROS) generation, and uPA inhibitory activity were characterized. In vitro studies included cellular uptake, cytotoxicity, and invasion assays. In vivo therapeutic efficacy was evaluated in subcutaneous CT26 tumor models and lung metastasis models, with biosafety assessed by body weight monitoring. Results: PINPs exhibited uniform spherical nanostructure, prolonged blood circulation, and enhanced tumor accumulation via the enhanced permeability and retention (EPR) effect. Under 680 nm irradiation, PINPs generated robust ROS and induced tumor cell apoptosis. PINPs potently inhibited uPA activity and suppressed tumor cell invasion. In vivo, PINPs plus PDT achieved significant tumor growth inhibition (73.6%) and strong anti-metastatic efficacy (60.7%), superior to free IG2. No obvious systemic toxicity was observed. Conclusions: The dual-functional PINPs achieve short-term acute tumor ablation via PDT and sustained anti-metastatic potential via uPA inhibition within the tested observation windows, with favorable biosafety. This carrier-free self-assembly strategy provides proof-of-concept validation and a generalizable design paradigm for developing synergistic anti-metastatic nanotherapeutics against metastatic CRC. Full article

Plasminogen activator inhibitor-1 (PAI-1), encoded by SERPINE1, is the principal physiological inhibitor of tissue-type and urokinase-type plasminogen activators and a central regulator of fibrinolysis. Beyond its canonical hemostatic role, PAI-1 has emerged as a pleiotropic mediator of tissue remodeling, fibrosis, metabolic dysfunction, cancer progression, cellular senescence, and age-associated immune dysregulation. A central argument of this review is that PAI-1 should be understood not only as a downstream biomarker of aging-associated pathology, but also as an active effector linking senescence-associated secretory phenotype (SASP) signaling, chronic low-grade inflammation, impaired immune surveillance, fibrotic extracellular matrix remodeling, and a prothrombotic state. In this framework, PAI-1 may function as an immune-aging checkpoint: a molecular node through which senescent, stromal, malignant, and inflammatory cells reinforce immune evasion and tissue dysfunction. Structure-guided drug discovery has enabled the development of small-molecule PAI-1 inhibitors, including TM5275, TM5441, TM5509, and TM5614. Among these, TM5614 is an orally available investigational compound that has progressed to clinical evaluation. Preclinical studies support anti-thrombotic, anti-fibrotic, anti-inflammatory, anti-senescent, and tumor-microenvironment-modulating effects of PAI-1 inhibition, while early clinical studies have evaluated TM5614 in chronic myeloid leukemia, immune-checkpoint-refractory malignant melanoma, non-small-cell lung cancer, and COVID-19-associated pneumonia. This review summarizes the biology of PAI-1, expands the discussion of immunoaging, reviews representative preclinical and clinical data, compares available PAI-1 inhibitors, and discusses the translational opportunities and safety considerations for TM5614 and related compounds. Full article

Diabetes mellitus (DM) is a complex metabolic disorder associated with a heightened risk of cardiovascular events, largely driven by a hypercoagulable and hypofibrinolytic state. The pathophysiological interplay between chronic hyperglycemia, oxidative stress, insulin resistance, and systemic inflammation fosters profound alterations in the coagulation cascade, endothelial function, and platelet activity. This narrative review synthesizes evidence from studies published between 2008 and 2026, focusing on coagulation and platelet-related biomarkers selected based on their biological relevance to thrombosis, endothelial dysfunction, and inflammation, as well as the availability of clinical and interventional data across different forms of DM. Although there are numerous biomarkers involved in the pathogenesis of various forms of diabetes, this narrative review critically examines key coagulation biomarkers—including D-dimer, fibrinogen, prothrombin, tissue thromboplastin or tissue factor, P-selectin, soluble urokinase plasminogen activator receptor, thrombomodulin, plasminogen activator inhibitor-1, von Willebrand factor, and β-thromboglobulin—across distinct diabetes subtypes, including type 1, type 2, gestational, and secondary forms linked to endocrinopathies and pancreatic diseases. The literature reveals substantial subtype-specific heterogeneity in hemostatic alterations. For instance, Type 1 DM is characterized by early endothelial dysfunction and platelet activation, while Type 2 DM presents with elevated coagulation factors, impaired fibrinolysis, and a proinflammatory milieu. Gestational DM exhibits pregnancy-specific changes in coagulation, yet distinguishing them from obesity-related effects remains challenging. Secondary diabetes forms, such as those associated with Cushing’s syndrome or pancreatitis, further underscore the diversity in thrombotic risk profiles. Among the coagulation and platelet activation biomarkers reviewed, fibrinogen, P-selectin, and plasminogen activator inhibitor-1 demonstrate the most consistent associations with glycemic control, vascular dysfunction, and therapeutic modulation, particularly in type 2 diabetes, suggesting greater potential for clinical translation. In contrast, evidence for markers such as D-dimer, tissue factor or tissue thromboplastin, and soluble urokinase plasminogen activator receptor remains heterogeneous and insufficient for routine clinical application. By synthesizing mechanistic insights and clinical data, this review highlights the urgent need for subtype-tailored coagulation assessment in diabetes management. A better understanding of the dynamic alterations in coagulation pathways may facilitate earlier detection of vascular complications and inform personalized antithrombotic strategies. Full article

The high incidence of thrombosis in lymphoma is largely due to chronic inflammation and endothelial dysfunction. To elucidate the mechanisms underlying thrombus formation and fibrinolysis, we investigated interactions between circulating endothelial cells and peripheral blood mononuclear cells (MNCs), along with inflammatory signaling pathways, in patients with follicular lymphoma (FL), Hodgkin lymphoma (HL), and diffuse large B-cell lymphoma (DLBCL), independent of the presence of thrombosis, compared to healthy controls by flow cytometry, immunoblotting, and fluorometric assays. We observed increased tissue factor (TF) expression on CD31+ endothelial cells in DLBCL and FL. In DLBCL, inducible nitric oxide synthase expression was elevated in MNCs, while reduced nitrite levels correlated with an advanced clinical stage in patients with thrombosis. In lymphoma, nuclear factor kappa B (NFκB) signaling was activated in MNCs, while signal transducer and activator of transcription 3 (STAT3) activation was increased in DLBCL with thrombosis. Trans-endothelial migration of MNC was enhanced in HL, FL and DLBCL with thrombosis and reduced by inflammatory cytokine tumor necrosis factor alpha (TNF-α) that promoted platelet aggregation like interleukin-6 (IL-6) in HL and FL. Fibrinolytic analyses showed reduced tissue type plasminogen activator in lymphoma, whereas increased urokinase-type plasminogen activator (uPA) was linked to poorer total survival in DLBCL with thrombosis, suggesting a compensatory role in early thrombus resolution. These findings indicate that chronic inflammation promotes endothelial activation, dysregulated fibrinolysis, and increased vascular permeability, contributing to heightened thrombotic risk. This study provides mechanistic insight into lymphoma-associated thrombosis and identifies TF, uPA, and the inflammatory signaling pathways as potential biomarkers and therapeutic targets. Full article

Herbal melanin (HM), previously reported for its antiproliferative and pro-apoptotic properties, has garnered interest as a promising anti-colorectal cancer drug. However, HM’s biological effects and underlying molecular mechanisms and the related signaling pathways in colorectal cancer (CRC) cell motility are poorly investigated. To evaluate the impact of various concentrations (50, 100, and 200 μg/mL) of HM on cell migration, invasion, and tumorigenicity on human HT29 and SW620 CRC cell lines, a real-time cell analyzer instrument and colony formation assays were employed, respectively. An angiogenesis-related protein array was also used, and the levels of protein expression contributing to colony formation and extracellular proteolysis-driven cell migration and invasion, such as E-cadherin, N-cadherin and urokinase-type plasminogen activator receptor (uPAR), were monitored using Western blotting and RT-qPCR technologies. HM significantly decreased CRC cell motility, invasiveness, and formation of colonies, associated with E-cadherin upregulation and N-cadherin downregulation. In addition, HM specifically inhibited uPAR expression levels, which were also decreased by the pharmacological mitogen-activated protein kinase (MAPK) kinase (MEK) inhibitor UO126 and Jun N-terminal kinase (JNK) inhibitor SP600125, in both CRC cell lines, including metastatic CRC (mCRC) SW620 cell line. Addition of HM to cells pretreated with JNK and MEK inhibitors attenuated the blockade of JNK and ERK phosphorylation and alleviated HM-downregulated uPAR expression and HM-inhibited mCRC cell migration. In conclusion, our in vitro studies demonstrate that HM exhibits an inhibitory effect on CRC migration and invasiveness, associated with uPAR downregulation through JNK and ERK pathways. Full article

Cellular senescence, including replicative senescence (RS) and stress-induced premature senescence (SIPS), is a state of the permanent arrest of cell growth, which can occur in proliferative cells and post-mitotic cells. Cellular senescence is believed to contribute importantly to aging and aging-related diseases. Although several hypotheses, including telomere shortening, oncogene activation, oxidative stress, DNA damage, and mitochondrial dysfunction, have been proposed, the mechanisms underlying cellular senescence in either physiological or pathological conditions remain poorly understood. Plasminogen activator inhibitor 1 (PAI-1), a physiological inhibitor of tissue type and urokinase type of plasminogen activators (tPA and uPA), has multiple functions. PAI-1 expression increases with age and in many aging-related diseases. Importantly, increased PAI-1 expression is not only a marker but also a mediator of cell senescence induced by different stimuli in vitro and in vivo. This review focuses on the recent advance in the role of PAI-1 in cell senescence during aging and in aging-related diseases as well as the potential mechanisms by which PAI-1 promotes cell senescence. Full article

Background: Aberrant signalling through the urokinase-type plasminogen activator receptor (uPAR) is a key driver of tumour invasion and progression in prostate cancer, yet linking molecular-level perturbations to emergent spatial invasion phenotypes remains challenging. Methods: In this study, we developed a multiscale in silico framework combining molecular docking, mechanistic ordinary differential equation (ODE) modelling, and agent-based modelling (ABM) to investigate uPAR-driven invasion dynamics. Results: Molecular docking and MM-GBSA analyses were used to prioritise caffeic acid phenethyl ester (CAPE) as a candidate uPA/uPAR modulator, while uPAR inhibition was implemented mechanistically at the signalling level within the ODE model rather than through direct energetic parametrisation. Steady-state signalling outputs were mapped to effective proliferation and motility rates, which served as inputs to a spatial ABM of tumour invasion. The integrated simulations showed that uPAR inhibition results in statistically significant reductions in spatial invasion and tumour growth compared with baseline conditions, whereas enhanced uPA signalling produced only modest, non-significant trends. Conclusions: These findings demonstrate how subtle intracellular signalling perturbations can translate into pronounced population-level invasion phenotypes when embedded in a spatial context. Overall, the proposed digital-twin framework provides a coherent and extensible approach for connecting molecular prioritisation with quantitative predictions of tumour invasion behaviour in prostate cancer. Full article

In vitro maturation (IVM) of mammalian oocytes is an essential fertility option for patients at risk of ovarian hyperstimulation syndrome or needing urgent fertility preservation. However, poor outcomes indicate a limited understanding of the molecular mechanisms behind cumulus cell expansion and extracellular matrix (ECM) remodeling. This study investigated the role of serum-derived urokinase-type plasminogen activator (PLAU) in mouse oocyte IVM. Immature cumulus–oocyte complexes from CD-1 mice were cultured with or without serum, and PLAU activity was blocked using 4-chlorophenylguanidine hydrochloride. Cumulus expansion, oocyte maturation, and cumulus cell transcriptomes were analyzed. Serum supplementation enhanced cumulus expansion and maturation, while absence of serum or PLAU inhibition hindered both processes. External PLAU partially rescued these issues under serum-free conditions. Transcriptome analysis demonstrated that inhibiting PLAU activity reduces the expression of ovulation- and metabolism-related genes, such as those involved in glycolysis and carbohydrate metabolism, while increasing genes related to vesicle-mediated transport. PLAU is crucial for cumulus expansion and metabolic regulation during IVM, affecting ECM remodeling and oocyte quality. Supporting IVM culture media with proteolytic and metabolic factors could improve outcomes in assisted reproduction. Full article

This review reappraises the anti-inflammatory potential of the contact activation system (CAS) in intensive care through an evolutionary lens. The authors propose that coagulation factor XII (FXII) and related components evolved in terrestrial animals as a “foreign-surface sensing–immunothrombosis” module, helping to explain the minimal bleeding phenotype of FXII deficiency and the secondary loss of F12 in marine mammals. CAS shares components with the kallikrein–kinin system (KKS): alpha-coagulation factor XIIa (α-FXIIa) drives coagulation factor XI (FXI) activation to amplify coagulation, whereas betacoagulation factor XIIa (β-FXIIa) activates the KKS to generate bradykinin, promoting vasodilation and vascular leak. Beyond proteolysis, zymogen FXII signals via urokinase-type plasminogen activator receptor (uPAR) to induce neutrophil extracellular trap formation (NETosis), thereby amplifying immunothrombosis. Clinically, the relevance spans sepsis and extracorporeal organ support: pathogens can hijack CAS/KKS to facilitate invasion, and artificial surfaces such as extracorporeal membrane oxygenation (ECMO) circuits chronically trigger contact activation. In animal models, selective inhibition of FXII/FXI prolongs circuit life and attenuates pulmonary edema and inflammation without materially increasing bleeding. The review also catalogs “non-coagulation” roles of CAS members: Activated coagulation factor XI (FXIa) modulates endothelial permeability and smooth-muscle migration, and the FXII heavy chain exhibits direct antimicrobial activity—underscoring CAS as a nexus for coagulation, inflammation, and host defense. Overall, CAS inhibitors may couple “safe anticoagulation” with “cascade-level anti-inflammation,” offering a testable translational path for organ protection in the ICU alongside infection control and informing combined, precision strategies for anticoagulation and anti-inflammatory therapy. Full article

As a continuation of Part I on the structure and regulation of factor VII-activating protease (FSAP), this narrative review synthesizes mechanistic, translational, and limited clinical evidence to delineate FSAP’s roles at the interface of coagulation and fibrinolysis. Current evidence indicates that FSAP enhances thrombin generation primarily via proteolytic inactivation of tissue factor pathway inhibitor (TFPI), whereas direct activation of factor VII (FVII) by FSAP appears weak or context-restricted. Beyond plasma proteins, FSAP can upregulate tissue factor (TF) in human macrophages, while platelet-related effects remain insufficiently substantiated. On the fibrinolytic axis, FSAP indirectly accelerates clot lysis by converting single-chain urokinase (scuPA) to its active two-chain form (tcuPA) and, less efficiently, by processing tissue-type plasminogen activator (tPA); in addition, selective cleavage of fibrinogen Aα and Bβ chains remodels clot architecture, yielding thinner fibers with higher density and increased susceptibility to proteolysis. Collectively, the data position FSAP as a context-sensitive modulator of thrombin generation and fibrin turnover. Key gaps include isoform specificity, in vivo cellular targets, and the quantitative contribution of the FSAP-TFPI and FSAP–fibrinogen–urokinase/tPA axes in human pathophysiology, which warrant focused mechanistic and clinical studies. Full article

The urokinase-type plasminogen activator receptor (uPAR) plays a pivotal role in regulating extracellular proteolysis, cell migration, immune responses, and tissue remodeling across diverse physiological and pathological contexts. This review provides detailed insights into the structure of uPAR, ligand interactions, and signaling mechanisms, emphasizing its central function in cancer progression, including tumor invasion, metastasis, angiogenesis, and modulation of the tumor microenvironment. We also summarize the involvement of uPAR as a key player in cardiovascular, infectious, and neurological diseases, where it contributes to inflammation, tissue damage, and disease progression. However, translational gaps remain, most notably inconsistent assay harmonization (especially for suPAR), uncertain context-specific cut-offs and patient-selection criteria and limited multicenter validation for uPAR-targeted imaging and therapeutics. This review addresses these gaps by synthesizing cross-disease evidence to clarify clinical use cases and outline practical selection frameworks. Furthermore, we discuss the clinical potential of uPAR as a diagnostic and prognostic biomarker in diverse disease contexts, along with recent advances in therapeutic strategies targeting uPAR. Full article

Autoimmune diseases arise from complex interactions of genetic, environmental, and hormonal factors, yet their precise causes remain elusive. Beyond its canonical role in fibrin degradation, the fibrinolytic system is increasingly recognized as both a pathogenic driver and a regulatory modulator in autoimmunity. Key factors—plasminogen (Plg), plasmin, α2-antiplasmin (α2AP), tissue-type plasminogen activator (tPA), urokinase-type plasminogen activator (uPA), its receptor (uPAR), and plasminogen activator inhibitor-1 (PAI-1)—not only reflect secondary responses to vascular and immune dysregulation but also actively shape innate and adaptive immunity. They influence macrophage activation, dendritic cell maturation, T cell responses, and cytokine production, thereby bridging coagulation, inflammation, and tissue repair. This review integrates current evidence on the dual pathogenic and regulatory roles of fibrinolytic factors, organizing autoimmune diseases into systemic, organ-specific, and secondary syndromes. We further discuss how the imbalance of fibrinolysis can either promote inflammatory persistence or, conversely, facilitate resolution through fibrin clearance and immune homeostasis. By highlighting this bidirectional influence, the review aims to refine our understanding of fibrinolytic components as both contributors to and regulators of autoimmune disease pathogenesis. Full article

Systemic sclerosis (SSc) is an autoimmune disease associated with a high burden of morbidity and mortality due to organ complications. Pulmonary arterial hypertension (PAH) and cardiac involvement, characterized by chronic right ventricular (RV) pressure overload with consequent RV dysfunction and ultimately right heart failure (HF), are among these. A common comorbidity in SSc is chronic kidney disease (CKD). CKD is often present at the time of PAH diagnosis or a decline in renal function may occur during the course of the disease. CKD is strongly and independently associated with mortality in patients with PAH and HF. The cardiovascular and renal systems are closely interconnected, and disruption of this balance may result in cardiorenal syndrome (CRS). Type 2 CRS refers to CKD as a consequence of chronic HF. In clinical practice, non-specific markers such as troponin, B-type natriuretic peptide (BNP), N-terminal pro-BNP (NT-proBNP), and serum creatinine aid in CRS diagnosis. More specific biomarkers, including cystatin C (CysC), neutrophil gelatinase-associated lipocalin (NGAL), galectin-3, and soluble urokinase plasminogen activator receptor (suPAR), have shown value for diagnosis and prognosis in CRS. This study aimed to evaluate comprehensively heart/kidney damage markers related to CRS in SSc patients compared with healthy controls (HC) and to examine their association with renal and cardiac ultrasound parameters. SSc patients showed significantly higher CRS markers than HC (p < 0.001). SSc patients with clinically diagnosed CRS had significantly elevated galectin-3, suPAR, sNGAL, and uNGAL levels (p < 0.05) than SSc patients without CRS. Positive correlations were found between renal resistive index (RRI) and NT-proBNP (r = 0.335, p < 0.05), and between RRI and suPAR (r = 0.331, p < 0.05). NT-proBNP, suPAR, galectin-3, sNGAL, and uNGAL emerge as promising biomarkers for the early detection of cardiac and renal involvement in SSc patients. Full article

This narrative review explores the intricate relationship between the plasminogen activator system (PAS), comprising urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA), and a range of neuropsychiatric disorders, including depression and anxiety. By synthesizing existing preclinical and clinical evidence, we clarify the roles of uPA and tPA in the pathogenesis and potential treatments of these conditions. This narrative review emphasizes their involvement in modulating neuronal plasticity, synaptic remodeling, and neurotransmitter systems, which are pivotal in maintaining brain function and behavior. Additionally, this review highlights key mechanisms by which these activators influence the neurobiological processes underlying mood and cognitive dysfunction. Critical analysis identifies areas of consensus, such as the role of plasminogen activators in neuroinflammation and stress responses, while also addressing gaps and controversies in the literature. The findings underscore the therapeutic potential of targeting the uPA/tPA system for innovative interventions. By offering a nuanced understanding of their contributions to mood disorders, this review aims to inspire future research toward developing novel, mechanism-based treatment strategies that harness the PAS’ capacity to restore neural homeostasis and improve patient outcomes. Full article