Search Results (358)

Enolase-1 (ENO-1) is classically known as a highly conserved glycolytic enzyme that catalyzes the conversion of 2-phosphoglycerate to phosphoenolpyruvate in the final steps of glycolysis. This enzyme, however, is being increasingly implicated as a multifunctional moonlighting protein with compartment-specific roles in inflammation. Within the cytosol, ENO-1 regulates macrophage inflammation during sepsis; on the cell surface, it functions as a plasminogen receptor, and extracellularly, it can participate in innate immune signaling. Across innate and adaptive immunity, ENO-1 has been implicated in macrophage activation, neutrophil recruitment, endothelial cell dysfunction, fibroblast remodeling, and autoantigenicity. These functions have been linked to sepsis, acute respiratory distress syndrome, acute organ injury, hemorrhagic shock, rheumatoid arthritis, and cancer-associated inflammation in the tumor microenvironment. Therapeutic targeting of ENO-1 includes small-molecule inhibitors and monoclonal antibodies. ENO-1, with its compartment-specific functions in disease pathogenesis, serves as a significant therapeutic target for inflammatory diseases. In this review, we discuss the novel compartment-specific roles of ENO-1 in inflammatory diseases, defining its functions beyond its role in glycolysis. We conclude that both the metabolic and moonlighting functions of ENO-1 contribute to inflammation, and future studies should delineate its compartment-specific roles in inflammatory pathophysiology, as compartment-specific targeting may represent the future of ENO-1-directed therapy. 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

A bioengineered version of recombinant tissue plasminogen activator, i.e., tenecteplase (TNK-tPA), was designed to have a longer half-life, resistance to plasminogen activator inhibitor-1, and fibrin-targeted plasminogen activation. By comparison to tPA, clinical trials suggest that TNK-tPA may be less susceptible to the effects of alpha2-antiplasmin (α2AP), the primary inhibitor of thrombus dissolution. However, preclinical studies are limited, and whether α2AP affects TNK-tPA’s fibrinolytic activity or efficacy in experimental ischemic stroke is unknown. We examined the effects of TNK-tPA and α2AP on the dissolution of human plasma clots (in vitro) and experimental ischemic brain injury from stroke induced by transient middle cerebral artery ischemia. TNK-tPA induced a dose-dependent increase in plasma clot dissolution; inhibition of α2AP with a specific monoclonal antibody caused a synergistic increase in TNK-tPA-mediated clot dissolution. In experimental ischemic stroke with ischemia and reperfusion, TNK-tPA treatment of α2AP^−/− mice significantly reduced ischemic infarct volume, brain swelling, brain hemorrhage, and neurobehavioral disability vs. TNK-tPA-treated α2AP^+/+ (C57BL/6 background) mice with normal α2AP levels (p < 0.05 to p < 0.0001). α2AP impairs the dissolution of human clots in vitro by TNK-tPA and significantly exacerbates ischemic brain injury, swelling, hemorrhage, and neurobehavioral disability after experimental stroke, even with reperfusion. Targeting α2AP may improve the efficacy of TNK-tPA and reduce hemorrhagic complications. Full article

Background/Objectives: Given the rising prevalence of overweight and obesity in pediatric populations, identifying effective nutritional interventions for metabolic management is crucial. Beyond their nutritional value, soy and lupin proteins are recognized for their bioactive properties. We formulated two protein-enriched functional beverages and evaluated their impact on the metabolic profile and gut microbiota of adolescent boys with overweight or obesity. Methods: A randomized, double-blind clinical trial was conducted with 30 Mexican male adolescents (12–16 years old). Participants were randomly assigned to consume a functional beverage providing a daily 10 g portion of either soy or lupin protein for 5 weeks. Results: Following the intervention, both groups exhibited significantly attenuated fasting glucose (soy: 93.1 vs. 99.5 mg/dL; lupin: 92.3 vs. 97.9 mg/dL) and C-peptide levels. Consequently, insulin sensitivity, assessed via the HOMA2 index, improved significantly in both cohorts. The soy protein group showed a marked reduction in total cholesterol (–10.4%) and triglycerides (–17.1%). Furthermore, serum levels of plasminogen activator inhibitor-1 (PAI-1) and visfatin were decreased after both interventions. A post-treatment reduction in glucose-dependent insulinotropic polypeptide (GIP) was specifically observed in the lupin group. Regarding the gut microbiota, both protein-based beverage interventions correlated with enhanced 16S rDNA diversity and increased the abundance of the Bacillota phylum and butyryl-CoA transferase-positive bacteria. Conclusions: Our data suggests that the daily consumption of soy or lupin protein-based beverages could exert beneficial metabolic and endocrine effects in adolescent boys with overweight and obesity, potentially mediated by the modulation of the gut microbiome. Full article

Glioblastoma (GBM) is an extremely invasive and incurable tumor. We previously reported predominant ALDH1A3 expression at the invasive front of GBM tumors, which was associated with shorter patient survival, and further showed that ALDH1A3 promoted tumor angiogenesis involving plasminogen activator inhibitor-1 (PAI-1). Here, we investigated whether ALDH1A3 drives cell invasion through retinoic acid (RA) and PAI-1 signaling. Analysis of the TCGA-GBM dataset revealed a positive association between ALDH1A3 and PAI-1 (SERPINE1) expression. Overexpression of ALDH1A3 in GBM cells markedly increased PAI-1 mRNA and protein levels, with cellular colocalization of both proteins, accompanied by robust migration and invasion. These effects were reversed by treatment with a pan-RA receptor (RAR) antagonist AGN193109 (AGN), with a specific PAI-1 inhibitor tiplaxtinin (Tip) or by CRISPR/Cas9-mediated knockout of PAI-1. In a chick chorioallantoic membrane (CAM) model, ALDH1A3-overexpressing cells showed increased invasion, which was reduced by tiplaxtinin (Tip) treatment or PAI-1 knockout. Mechanistically, ChIP-qPCR demonstrated that RA treatment or ALDH1A3 overexpression increased RARα occupancy at the PAI-1 regulatory region, accompanied by increased PAI-1 expression, both of which were diminished by AGN. Collectively, the present study defines an ALDH1A3-RA-PAI-1 signaling axis that contributes to GBM cell motility and invasion. Full article

Sepsis is a systemic disorder in which infection-induced inflammation progressively disrupts vascular homeostasis and drives organ dysfunction. This review reframes septic pathophysiology as a sequential and self-amplifying process centered on endothelial failure. Early activation of innate immune pathways by pathogen- and damage-associated molecular patterns promotes cytokine release, oxidative stress, and enzymatic degradation of the endothelial glycocalyx. Loss of this protective surface layer exposes endothelial cells to unbuffered inflammatory and mechanical injury, impairing mechanotransduction, increasing leukocyte and platelet adhesion, and destabilizing vascular barrier function. Subsequent disruption of intercellular junctions promotes capillary leakage, tissue edema, and impaired oxygen diffusion, while mitochondrial dysfunction and redox imbalance reduce endothelial repair capacity. In parallel, complement activation, neutrophil extracellular trap formation, platelet–leukocyte interactions, and loss of anticoagulant signaling shift the microvasculature toward a prothrombotic and proinflammatory state. These interconnected mechanisms culminate in microvascular incoherence, characterized by heterogeneous capillary flow, regional hypoxia, impaired oxygen extraction, and progressive organ failure despite apparent restoration of systemic hemodynamics. Within this framework, biomarkers such as syndecan-1, soluble thrombomodulin, angiopoietin-2, von Willebrand factor, and plasminogen activator inhibitor-1 are best interpreted as mechanistic readouts of glycocalyx shedding, endothelial injury, permeability imbalance, and thromboinflammatory activation. Understanding sepsis as an evolving endothelial pathophysiological process provides a coherent framework for integrating inflammation, vascular leakage, hypoxia, coagulation, and organ dysfunction while identifying mechanistic biomarkers that reflect distinct stages of microvascular collapse. Full article

Urokinase plasminogen activation system regulates the activation of plasminogen to produce the ubiquitous extracellular protease plasmin. It is involved in different physiological and pathophysiological processes, which involve tissue reorganization, wound healing, cell migration and invasion, etc. The system comprises urokinase plasminogen activator, an extracellular protease, its inhibitor plasminogen activator inhibitor PAI1 and urokinase receptor, uPAR. The system is regulated at the level of transcription and posttranscriptionally, and the net urokinase activity depends on the balance between urokinase and PAI1. Promoters of urokinase, PAI1 and uPAR are regulated through different signaling pathways, mostly MAP kinases and TGFβ signaling. Urokinase promoter is complex and mostly depends on strong enhancers containing AP1/ETS binding sites for different combinations of AP1 dimers, whose members are phosphorylated through ERK, JNK and p38 kinases. The PAI1 promoter is mainly regulated through TGFβ signaling, which can use both Smad and AP1-dependent transcription. The uPAR promoter also depends on AP1 signaling, in addition to other transcription factors activated through other pathways. Although activated through common pathways, each of the promoters has specific regulation as a consequence of a signaling network, which enables fine-tuning of the system and urokinase activity according to the physiological needs. 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

Background/Objectives: Late-onset Alzheimer’s disease (LOAD) is a multifactorial neurodegenerative disorder involving the interaction of genetic and environmental factors. Dysregulation of the fibrinolytic system, particularly an increase in plasminogen activator inhibitor-1 (PAI-1) levels, may contribute to Alzheimer’s pathology. Vitronectin (VTN) regulates fibrinolysis by stabilizing PAI-1. This study investigated the relationships between plasma PAI-1 activity and VTN, SERPINE1 (PAI-1), and APOE gene variants in nineteen LOAD patients (>65 years) and ten cognitively normal age-matched control groups. Methods: Targeted next-generation sequencing was used to analyze the VTN, APOE, and SERPINE1 genes in 19 LOAD patients and ten controls. Additionally, plasma PAI-1 activity was measured in both groups. Results: Plasma PAI-1 activity was statistically significantly higher in LOAD patients compared to controls (p = 0.04). Targeted next-generation sequencing results showed that VTN 5′-UTR variants (rs7212814, rs1555584131, rs71135830, and rs11437594) were found in all patients and observed in 20% of controls (p = 0.0001). The VTN rs704 variant was detected in 84% of patients and 29% of controls (p = 0.001). VTN 5′-UTR variants showed Spearman correlation with PAI-1 activity (r = 1.0; p < 0.0001). SERPINE1 3′-UTR variants (rs11178, rs41423845) were found to be associated with the disease (p = 0.027; p = 0.0001). The APOEε3/ε4 genotype was present in 52.6% of patients and was not associated with PAI-1 activity. VTN variants showed an association with LOAD. Conclusions: These findings suggest that VTN variants may contribute to LOAD pathogenesis by affecting PAI-1 and leading to fibrinolytic system dysregulation. 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

Endovascular aneurysm repair (EVAR) is a widely used minimally invasive treatment for abdominal aortic aneurysms. However, postoperative type II endoleak (T2EL) remains a relevant complication associated with a risk of aneurysm rupture and the need for repeated imaging follow-up, resulting in exposure to ionizing radiation. Identification of biological factors predisposing to T2EL may improve risk stratification. This pilot study aimed to investigate whether disturbances in hemostasis are associated with early T2EL development after EVAR. A total of 103 patients treated with EVAR for symptomatic or asymptomatic abdominal aortic aneurysms in a tertiary vascular center were prospectively enrolled. Blood samples were collected preoperatively and one month postoperatively to assess fibrinogen, prothrombin fragment F1+2 (F1+2), thrombin–antithrombin complex (TAT), tissue plasminogen activator antigen (tPA), plasminogen activator inhibitor-1 (PAI-1) activity, and platelet activity. Computed tomography angiography (CTA) during follow-up was used to detect endoleaks and calculate their volume. Patients with T2EL had significantly lower levels of prothrombin fragment F1+2 and higher PAI-1 activity compared with patients without endoleak. No significant association was observed between the analyzed biomarkers and endoleak volume. These findings suggest that reduced thrombin generation and impaired fibrinolysis may contribute to endoleak formation after EVAR and warrant further investigation in larger, confirmatory studies. 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

The SERPINE1 gene encodes the serine protease inhibitor plasminogen activator inhibitor type-1 (PAI-1), a major negative regulator of the plasmin-dependent pericellular proteolytic cascade and a crucial determinant in the program of stromal remodeling. Recent omics approaches confirmed that high tumor SERPINE1 levels are prognostic for poor disease outcomes and shorter disease-free survival in various malignancies. Kinetic analysis of biomarkers of cell cycle transit in growth-synchronized p53 dual mutant human keratinocytes confirmed that PAI-1 transcription occurred early after growth activation of quiescent (G₀) cells and prior to G1 entry. Previous evidence has confirmed that differential residence of USF family members (USF1→USF2 switch) at the PE2 region hexanucleotide E box motif (CACGTG) in the SERPINE1 proximal promoter characterizes the G₀→G₁ transition period and the transcriptional status of the SERPINE1 gene. A consensus PE2 E box motif (5′-CACGTG-3′) at nucleotides −566 to −561 is required for USF occupancy of the PE2 E box and serum-stimulated SERPINE1 transcription. Interference with USF2 occupancy of the PE2 E Box site by a double-stranded PE2 “decoy”, or induced expression of a dominant-negative USF (A-USF) construct, attenuate serum- and TGF-β1-stimulated SERPINE1 synthesis. Tet-Off activation of an A-USF insert reduced both PAI-1 and PAI-2 transcripts while increasing the fraction of proliferating (Ki-67⁺ cells). Conversely, overexpression of USF2 or adenoviral delivery of a PAI-1 vector inhibited HaCaT colony expansion. These findings are discussed in this review and collectively suggest that the USF1→USF2 transition at the PE2 E box site and subsequent SERPINE1 transcription impact serum-stimulated keratinocyte growth and, likely, cell cycle progression. 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

Chondrosarcomas (ChSs) are mesenchymal chemo- and radiation-resistant tumors, representing the second most frequently diagnosed bone sarcoma after osteosarcoma and 20% of all bone sarcomas. Most of ChS patients have a good prognosis after complete surgical resection. Conversely, patients with inoperable disease, due to the tumor location or metastatic dissemination, represent a great clinical challenge due to the lack of effective therapeutic options. In this study, to the best of our knowledge, we document, for the first time in human ChS tissues, the existence of CD-31- and Podoplanin-negative vascular-like channels containing red blood cells, allowing us to hypothesize the occurrence of vasculogenic mimicry (VM) in ChSs. By using patient-derived ChS cells and a stabilized ChS cell line, we demonstrate that ChS cells are able to form in vitro tubules apparently similar to those formed by endothelial cells. Further characterization of these vessels revealed the pivotal role of the Urokinase Plasminogen Activator Receptor (uPAR) in mediating the capability of ChS cells to form VM. Finally, we provide evidence that, unlike bevacizumab, which did not exert any effect, the uPAR-derived antiangiogenic peptide RI-3 behaves as a potent inhibitor of VM. Full article