Therapeutic Potentials of Cerastes cerastes Venom: A Comprehensive Review of Bioactive Molecules and Biomedical Applications.

Persulfate-driven free radical depolymerization of fucosylated chondroitin sulfate and intrinsic Xase inhibition of the resulting oligosaccharides.

A Synthetic Anticoagulant Octaparin Attenuates Renal Ischemia-Reperfusion Injury via DC-SIGN/NF-κB Signaling.

HighlightsWhat are the main findings?Au25(SG)18, a nanoscale gold cluster with low electrophilicity, accumulates in vascular endothelial cells at low cell density and suppresses perlecan expression by inactivating ADP-ribosylation factor 6 (Arf6).Au25(SG)18 also decreases biglycan expression in vascular endothelial cells at low cell density; however, the underlying mechanisms remain unclear.What are the implications of the main findings?This study suggests that organic–inorganic hybrid molecules modulate Arf6-mediated protein transport to the extracellular space, revealing a novel mechanism for proteoglycan synthesis regulation.Arf6-mediated extracellular transport plays a critical role in maintaining vascular homeostasis, serving as a potential target to modulate endothelial function and vascular diseases.Proteoglycans are macromolecules consisting of a core protein and one or more glycosaminoglycan side chains. Proteoglycans synthesized by vascular endothelial cells modulate various functions such as anticoagulant activity and vascular permeability. We previously reported that some heavy metals interfere with proteoglycan expression, and that organic–inorganic hybrid molecules, such as metal complexes and organometallic compounds, serve as useful tools to analyze proteoglycan synthesis mechanisms. However, the effects of metal compounds lacking electrophilicity on proteoglycan synthesis remain unclear. Au25(SG)18, a nanoscale gold cluster consisting of a metal core protected by gold–glutathione complexes, exhibits extremely low intramolecular polarity. In this study, we investigated the effect of Au25(SG)18 on proteoglycan synthesis in vascular endothelial cells. Au25(SG)18 accumulated significantly in vascular endothelial cells at low cell density and suppressed the expression of perlecan, a major heparan sulfate proteoglycan in cells, by inactivating ADP-ribosylation factor 6 (Arf6). Additionally, Au25(SG)18 reduced the expression of biglycan, a small dermatan sulfate proteoglycan, in vascular endothelial cells at low cell density; however, the underlying mechanisms remain unclear. Overall, our findings suggest that organic–inorganic hybrid molecules regulate the activity of Arf6-mediated protein transport to the extracellular space and that perlecan is regulated through this mechanism, highlighting the importance of Arf6-mediated extracellular transport for maintaining vascular homeostasis.

Unfractionated heparin (UFH) remains a major anticoagulant therapy applied within the acute hospital system. Due to intra- and interpatient variability, UFH monitoring needs to be applied to ensure patients remain free of thrombotic and bleeding complications at too low and too high an UFH level, respectively. Monitoring of UFH therapy is usually achieved using either an activated partial thromboplastin time (aPTT) or an anti-factor Xa (anti-Xa) method. The former is a clotting assay that evaluates both the anti-factor IIa (anti-IIa or anti-thrombin) and anti-Xa anticoagulant activity of UFH and the latter is a chromogenic assay that evaluates just the anti-Xa anticoagulant activity of UFH. The aPTT method is perhaps more widely utilized since aPTT testing is performed by all hemostasis laboratories performing routine coagulation tests. However, the aPTT method requires establishment of an aPTT UFH therapeutic range. The anti-Xa method is favored in larger hospital sites and by most experts and uses a standard UFH therapeutic range. We report findings for aPTT and anti-Xa testing for UFH monitoring in our geographic region using recent data (testing for the past 5 years; 2020-2024 inclusive) from the Royal College of Pathologists of Australasia Quality Assurance Program, an international external quality assessment (EQA) program, with over 110 enrolments for this EQA module. Four samples are assessed each year, with these comprising various levels of UFH. Good reproducibility was observed for duplicate samples sent in different surveys. Coefficient of variation (%) data revealed moderate variation for samples containing UFH (10-40% for anti-Xa; 10-25% for aPTT). Anti-Xa reagents containing dextran sulphate tended to yield higher anti-Xa values than those without. Interpretations regarding UFH levels being below, within, or above therapeutic levels were generally reported as expected, according to the level of UFH present in the sample, especially for anti-Xa testing.

The development of a biocompatible antidote that can efficiently neutralize the anticoagulation activity of both unfractionated heparin (UFH) and low-molecular-weight heparins (LMWHs) represents an unmet medical need. Here, we report that a piperazine-derived tetracationic macrocycle can efficiently neutralize both UFH and LMWHs, including dalteparin, enoxaparin, and nadroparin. In vitro and in vivo assays reveal that the compound outperforms protamine, exhibiting significantly improved neutralization activity, a broad therapeutic window for all heparins, and high biocompatibility, which is confirmed by its very low coagulation and hemolysis effect, as well as a high therapeutic index (20.5), defined as the ratio of the maximum tolerated dose to the effective therapeutic dose. Molecular dynamics simulations indicate that binding may occur through interlocked threading and direct contact patterns, which are stabilized by intermolecular hydrogen bonding and ion-pair electrostatic attraction.

Ginger (Zingiber officinale Roscoe)-derived natural compounds inhibit vitamin K-dependent carboxylation: a novel possibility for traditional Chinese medicine-induced bleeding risk.

Marine macroalgae represent a versatile and sustainable platform within blue biotechnology, offering structurally diverse polysaccharides that are making significant contributions to next-generation therapeutical applications. Algae are rich sources of high-value biomolecules, including polysaccharides, vitamins, minerals, proteins, antioxidants, pigments and fibers. Algal biomolecules are widely explored in modern pharmaceuticals due to their range of physiochemical and biological properties. Recently, algal polysaccharides have gained increasing attention in nanomedicine due to their biocompatibility, biodegradability and tunable bioactivity. The nanomedical applications of algal polysaccharides pertain to their anti-coagulant, antiviral, anti-inflammatory, antimicrobial and anti-cancer properties. In this review, we discuss some major macroalgal polysaccharides, such as agar, agarose, funoran, porphyran, carrageenan, alginate and fucoidan, as well as their structure, uses, and applications in nanomedical systems. Both sulfated and non-sulfated polysaccharides demonstrate significant therapeutic properties when engineered into their nanotherapeutic forms. Previous studies show antimicrobial potential of 80-90% antiviral activity > 70%, significant anticoagulant activity, and excellent anticancer responses (up to 80% reductions in cancer cell viability have been reported in nanoformulated versions of polysaccharides). This review discusses structure-function relationships, bioactivities, nanomaterial synthesis and nanomedical applications (e.g., drug delivery, tissue engineering, biosensing, bioimaging, and nanotheranostics). Overall, this review reflects the potential of algal polysaccharides as building blocks in sustainable biomedical engineering in the future healthcare industry.

An accurate and reproducible method to measure snake venom anticoagulant activity.

ABSTRACT Protein aggregation is an important pathological feature of cardiovascular disease. Therein, thrombin‐mediated fibrin aggregation is one of the mechanisms of thrombosis, accurate monitoring of which is significant for the research of thrombosis. In this study, the optical properties and theoretical calculations confirmed that the AIE probe could specifically illuminate fibrin aggregates without interference, and its signal response was positively correlated with thrombin activity. Therefore, the biosensing technique can realize in situ monitoring of the coagulation process and rapid identification of active substances in complex systems. Furthermore, to detect anticoagulant active monomers, a biosensing targeted affinity screening (BioSTAS) technology was established by combining the above biosensing technique with the affinity chromatography technique. The rapid identification of active substances was achieved through biosensing, and then active monomers were captured by affinity chromatography. As a result, two agents with anticoagulant activity, rhein and oleanolic acid, were discovered via the screening of more than 30 kinds of natural products and commercial preparations. This study not only provides a new idea for the application of AIE probes in the dynamic monitoring of protein aggregation but also establishes an innovative strategy for screening active agents from a complex system through the integration of biosensing and affinity chromatography technologies.

Enzymatic and chemical depolymerization of Fucus evanescens fucoidan: Impact on structure and hemostatic activity.

Traditional uses, chemical constituents, pharmacological activities and toxicology of Chinese medicinal leech (Shuizhi): A comprehensive review.

Venoms and toxins that induce anticoagulation in vitro do not cause major alterations in coagulation parameters in vivo in a mouse model.

Acellular tubular artery scaffolds offer structural support for vascular regeneration but are inherently limited by poor anticoagulant properties, which increases the risk of thrombus formation following implantation. This thrombogenicity remains a major obstacle to their clinical application, particularly in small-diameter vascular grafts. To address this challenge, the present study investigates the use of the Layer-by-Layer (LbL) assembly technique for heparin immobilization under low-speed rotation. Utilizing a roller tube system, heparin was immobilized onto decellularized scaffolds through electrostatic interactions facilitated by a DHI-based linker. This low-speed rotation LbL approach enhanced the uniformity and stability of heparin deposition compared to traditional static methods. One, 4, 7, 10, 13 deposition cycles were performed to achieve optimal heparin loading, resulting in scaffolds capable of sustained heparin release over 28 days. The heparinized scaffolds exhibited an initial burst release (approximately 80%), followed by a sustained phase with 18.24% ± 0.242 remaining to support prolonged anticoagulant activity. Importantly, the modified scaffolds significantly reduced thrombus formation and exhibited minimal hemolytic activity, indicating improved hemocompatibility. In addition to their antithrombotic properties, the scaffolds also promoted endothelial cell adhesion, which is critical for restoring vascular integrity, regulating vascular tone, and maintaining long-term patency. These findings highlight the efficacy of roller-assisted LbL heparinization as a practical and scalable strategy to enhance the blood compatibility of acellular vascular grafts. This method holds considerable promise for addressing thrombogenicity in vascular tissue engineering and advancing the clinical translation of bioengineered vascular constructs.

Potential anticoagulant mechanism of curdione: Enhancing thrombin inhibition by binding to AT-Ⅲ 's D-helix region.

Polysaccharide synthesis via chemical polymerization offers an efficient, facile, and cost-effective route to natural and mimetic polysaccharides with diverse biological and material properties. However, current polymerization-based approaches are largely restricted to low molecular weights (<50 kg/mol) and moderate stereoselectivity unlike their naturally derived counterparts where molecular weight is a key determinant of properties and function. Here, we report a robust strategy for constructing thiocarbonate-linked pseudo-polysaccharides via cationic ring-opening polymerization of readily accessible monosaccharide cyclic thionocarbonates. This polymerization proceeds with high reactivity and exclusive stereospecificity, affording pseudo-polysaccharides of high molecular weight (>500 kg/mol) across a variety of monosaccharide repeating units. Incorporation of a chain transfer agent (CTA) enables living polymerization, yielding polymers with predictable chain lengths and defined chain ends. Upon deprotection and sulfation, the resulting pseudo-polysaccharides exhibit strong fibroblast growth factor 2 (FGF2) binding and anticoagulant activity comparable to that of heparin, underscoring their potential as bioactive mimetics of biologically significant natural polysaccharides.

Background: Interest in the study of polysaccharides derived from higher plants is due to their high biological activity coupled with low toxicity. Polysaccharides and oligosaccharides extracted from the fruits and flowers of various hawthorn species (Crataegus spp.) exhibit diverse effects, including anticoagulant and hypolipidemic activities, as well as antioxidant and probiotic properties. Therefore, the study of the immunomodulatory properties of polysaccharides derived from the shoots of Alma-Ata hawthorn (Crataegus almaatensis Pojark.) and soft hawthorn (Crataegus submollis Sarg.) is of particular interest. Aim: The work aimed to study the immunotropic effects of water-soluble polysaccharides derived from the shoots of Alma-Ata hawthorn (Crataegus almaatensis Pojark.) and soft hawthorn (Crataegus submollis Sarg.). Methods: Water-soluble polysaccharides were derived from the shoots of Alma-Ata hawthorn and soft hawthorn by extraction followed by filtration, dialysis, and lyophilization. The water-soluble polysaccharides were injected intraperitoneally to C57BL/6 mice at a dose of 10 mg/kg; animals in the control group received 0.9% sodium chloride solution, and the comparison group received glucosaminylmuramyl dipeptide at a dose of 20 µg/kg for 10 days. The effects of the water-soluble polysaccharides on humoral and cell-mediated immune responses induced by sheep red blood cell immunization were evaluated. In in vitro experiments, water-soluble polysaccharides were added to the culture medium at a concentration of 20 µg/mL, and the production of IL-1β, TNF-α, and NO, arginase activity, cell proliferation in cultures of peritoneal macrophages, and the production of IL-2 and IFN-γ by cultures of mouse splenocytes were assessed. Results: Course administration of water-soluble polysaccharides derived from the shoots of Alma-Ata hawthorn and soft hawthorn stimulated the humoral immune response in experimental animals and did not affect the cell-mediated immune response. Addition of the polysaccharides derived from the shoots of Alma-Ata hawthorn and soft hawthorn to the culture medium increased the production of IL-1β and TNF-α, enhanced nitric oxide synthase activity, reduced arginase induction in macrophages, and increased both spontaneous IL-2 secretion and stimulated IFN-γ production by splenocytes from C57BL/6 mice. Conclusions: Administration of water-soluble polysaccharides derived from the shoots of Alma-Ata hawthorn and soft hawthorn resulted in an increased number of antibody-forming cells after immunization with sheep red blood cells and enhanced production of IL-1β, TNF-α, and NO by macrophages and IL-2 and IFN-γ by splenocytes from C57BL/6 mice. The studied polysaccharide samples showed no cytotoxicity against macrophages.

Background: Oxazolidinone derivatives are a novel class of synthetic antibacterial agents, characterized by a five-membered heterocyclic ring containing oxygen and nitrogen and a carbonyl functionality at position 2. This pharmacophore is responsible not only for antibacterial activity but also for a variety of other biological activities, including anticancer activity, anticoagulant activity, and several others. A series of novel oxazolidinone derivatives containing a hydroxamic acid moiety were synthesized in our laboratories and identified as potent inhibitors of the enzyme 5-lipoxygenase (5-LO), a key enzyme involved in the biosynthesis of leukotrienes (LTs). LTs are proinflammatory mediators implicated in allergic and inflammatory diseases. Currently, zileuton is the only FDA-approved 5-LO inhibitor, emphasizing the need to develop new agents for the treatment of such diseases. This project aims to develop validated stability-indicating analytical methods for the four most potent novel 5-(hydroxamic acid)methyl oxazolidinone derivatives (PH-211, PH-247, PH-249, and PH-251). Methods: The compounds were analyzed using Waters Acquity Ultra-High-Performance Liquid Chromatography (UHPLC-UV) with an ultraviolet detector to determine their stability in human plasma and under various forced degradation conditions, including acidic, basic, oxidative, and thermal conditions. Liquid chromatography–quadrupole time-of-flight mass spectrometry (LC-QToF-MS) was used to identify possible degradation products. Results: The compounds were found to be stable in human plasma and under thermal degradation conditions with high extraction recoveries (82–90%) but unstable in acidic, basic, and oxidative conditions. Conclusions: The findings show that the compounds are stable in biological conditions; they hold promise for the treatment of inflammatory and allergic diseases.

Hereditary protein C deficiency (PCD) increases thrombotic risk, but the molecular mechanisms of distinct missense variants remain incompletely defined. Two siblings from a family with recurrent deep vein thrombosis and a strong family history of thrombotic events were found to carry compound heterozygous PROC variants. To elucidate the biosynthetic and functional consequences of two PROC missense variants, c.632G > A (p.Arg211Gln) and c.1099G > A (p.Val367Met), and their combined impact on anticoagulant capacity. Two siblings with recurrent deep vein thrombosis were analyzed. Family segregation analysis was performed on multiple heterozygous carriers to support genotype-phenotype correlations. Recombinant protein C variants were expressed in HEK293T cells to assess expression efficiency and intracellular accumulation. Zymogen activation by thrombin-thrombomodulin and APC anticoagulant activity were evaluated using FVa degradation, clotting, and thrombin generation assays. Structural modeling and Na⁺-dependent enzymatic assays were performed to explore variant-specific mechanistic defects. Both variants exhibited partial expression defects, with p.Val367Met showing significantly increased intracellular accumulation and reduced secretion efficiency. p.Arg211Gln selectively impaired zymogen activation without affecting APC function (type IIa deficiency), whereas p.Val367Met preserved activation but reduced Na⁺-dependent catalytic efficiency (type IIb deficiency). Structural modeling revealed that Arg211 substitution disrupts activation peptide conformation, while Val367Met perturbs the Na⁺-binding loop adjacent to the S1 pocket. Co-inheritance of both resulted in synergistic anticoagulant impairment, leading to markedly elevated thrombin generation. These findings demonstrate that PCD pathophysiology can arise from combined biosynthetic and functional defects, with distinct structural perturbations differentially affecting zymogen processing and protease activity. Integrated genetic, biochemical, and structural analyses, in the context of family history and clinical phenotype, are essential for accurate variant interpretation. Understanding the specific molecular mechanisms of PROC variants can inform clinical decision-making, guide personalized anticoagulant therapy, and help prevent thrombotic events in affected individuals. Therapeutic strategies targeting zymogen activation or proteostasis may offer potential avenues to mitigate thrombotic risk in hereditary PCD.

In the search for effective and low-toxicity anticoagulantagents,the G-quadruplex-forming thrombin-binding aptamer (TBA) with sequence5′-GGTTGGTGTGGTTGG-3′, able to selectively recognizethe fibrinogen-binding exosite I of the thrombin enzyme, emerged asa promising therapeutic and surgical tool. In this frame, we recentlysynthesized and evaluated a library of TBA analogues carrying a naphthalenediimide (N) moiety and a 3-hydroxypropylphosphate (p) either at the 5′- or 3′-end of the TBA sequence.Interestingly, N-TBA-p and p-TBA-N analogues,having the same pendant groups at 5′- or 3′-end butin reversed position, showed very different behavior in terms of thermalstability, nuclease resistance in serum, and anticoagulant activity. N-TBA-p showed enhanced properties compared to both p-TBA-N and the parent TBA and thus emerged as a very promisingcandidate for future in vivo studies. Here, by in-depth moleculardynamics-based analyses, we disclosed the structural features determiningthe higher thermal stability and nuclease resistance as well as thehigher anticoagulant activity due to thrombin recognition, experimentallyobserved for N-TBA-p than p-TBA-N and TBA.