Search Results (2,008)

Background/Objectives: Direct oral anticoagulants (DOACs) are now the guideline-recommended alternative to vitamin K antagonists (VKAs) for long-term anticoagulation in patients with non-valvular atrial fibrillation. However, accurately assessing their impact on ischemic stroke outcomes remains challenging, primarily due to uncertainty regarding anticoagulation status at the time of hospital admission. This preliminary study addresses this gap by using point-of-care testing (POCT) to confirm DOAC activity at bedside, allowing for a more accurate comparison of 90-day functional outcomes between anticoagulated and non-anticoagulated stroke patients. Methods: We conducted a retrospective cohort study of 786 ischemic stroke patients admitted to the University of Pécs between February 2023 and February 2025. Active DOAC therapy was confirmed using the ClotPro^® viscoelastic testing platform, with ecarin Clotting Time (ECT) employed for thrombin inhibitors and Russell’s Viper Venom (RVV) assays for factor Xa inhibitors. Patients were categorized as non-anticoagulated (n = 767) or DOAC-treated with confirmed activity (n = 19). Mahalanobis distance-based matching was applied to account for confounding variables including age, sex, pre-stroke modified Rankin Scale (mRS), and National Institutes of Health Stroke Scale (NIHSS) scores at admission and 72 h post-stroke. The primary outcome was the change in mRS from baseline to 90 days. Statistical analysis included ordinary least squares (OLS) regression and principal component analysis (PCA). Results: After matching, 90-day functional outcomes were comparable between groups (mean mRS-shift: 2.00 in DOAC-treated vs. 1.78 in non-anticoagulated; p = 0.745). OLS regression showed no significant association between DOAC status and recovery (p = 0.599). In contrast, NIHSS score at 72 h (p = 0.004) and age (p = 0.015) were significant predictors of outcome. PCA supported these findings, identifying stroke severity as the primary driver of outcome. Conclusions: This preliminary analysis suggests that ischemic stroke patients with confirmed active DOAC therapy at admission may achieve 90-day functional outcomes comparable to those of non-anticoagulated patients. The integration of bedside POCT enhances the reliability of anticoagulation assessment and underscores its clinical value for real-time management in acute stroke care. Larger prospective studies are needed to validate these findings and to further refine treatment strategies. Full article

Specific venom immunotherapy (VIT) in patients with hymenoptera venom allergy (HVA) represents a well-studied approach to reduce the severity of a possible anaphylactic reaction. Currently, data on mechanisms of tolerance induction at the cellular level within the first hours of therapy are lacking. To address this, total and unoccupied high-affinity IgE receptor (FcεRI) numbers per basophil, soluble FcεRI (sFcεRI) and serum tryptase levels were measured before and after the first day of VIT induction in HVA patients. Additionally, basophil activation tests (BATs) were performed at those time points. In the early phase of VIT induction, no significant change in total FcεRI receptor density on basophils was observed, but a significant increase in unoccupied FcεRI was noticeable, predominantly in patients with high total IgE and low baseline unoccupied FcεRI density. No meaningful difference in serum tryptase levels or sFcεRI levels was observed after VIT induction. BATs showed heterogeneous results, often unchanged before and after VIT (in 47% of the cases), sometimes increased (in 40%) and only rarely decreased EC₅₀ sensitivity (in 13%). Changes in the BAT EC₅₀ correlated with FcεRI receptor density changes in basophils. In summary, VIT induction led to an increased ratio of unoccupied-to-total FcεRI without notable tryptase or sFcεRI serum elevation, pointing towards subthreshold cell activation with receptor internalization and recycling. However, the mostly unchanged or even increased basophil sensitivity in EC₅₀ calls for further research to clarify the clinical relevance of these rapid receptor modulations. Full article

The white-spotted jellyfish, Phyllorhiza punctata, is an invasive species with significant ecological and economic relevance spreading across various regions. While its ecological impact is well-documented, its molecular and biochemical characteristics remain poorly understood. In this study, we integrate proteomic data generated by LC-MS/MS with publicly available transcriptomic information to characterize P. punctata, analyzing differential protein expression across three distinct tissues: oral arms, mantle, and gonads. A total of 2764 proteins and 25,045 peptides were identified, including several venom components such as jellyfish toxins (JFTs) and phospholipase A2 (PLA2), which were further investigated and compared to toxins from other species. Enrichment analyses revealed clear tissue-specific functions. Additionally, deep learning and machine learning tools identified 274 promising AMP candidates, including the α-helical, β-sheet, and αβ-motif peptides. This dataset provides new insights into the protein composition of P. punctata and highlights strong AMP candidates for further characterization, underscoring the biotechnological potential of underexplored cnidarian species. Full article

Many vertebrates have evolved resistance to snake venom as a result of coevolutionary chemical arms races. In Australian skinks (family Scincidae), who often encounter venomous elapid snakes, the frequency, diversity, and molecular basis of venom resistance have been unexplored. This study investigated the evolution of neurotoxin resistance in Australian skinks, focusing on mutations in the muscle nicotinic acetylcholine receptor (nAChR) α1 subunit’s orthosteric site that prevent pathophysiological binding by α-neurotoxins. We sampled a broad taxonomic range of Australian skinks and sequenced the nAChR α1 subunit gene. Key resistance-conferring mutations at the toxin-binding site (N-glycosylation motifs, proline substitutions, arginine insertions, changes in the electrochemical state of the receptor, and novel cysteines) were identified and mapped onto the skink organismal phylogeny. Comparisons with other venom-resistant taxa (amphibians, mammals, and reptiles) were performed, and structural modelling and binding assays were used to evaluate the impact of these mutations. Multiple independent origins of α-neurotoxin resistance were found across diverse skink lineages. Thirteen lineages evolved at least one resistance motif and twelve additional motifs evolved within these lineages, for a total of twenty-five times of α-neurotoxic venoms resistance. These changes sterically or electrostatically inhibit neurotoxin binding. Convergent mutations at the orthosteric site include the introduction of N-linked glycosylation sites previously known from animals as diverse as cobras and mongooses. However, an arginine (R) substitution at position 187 was also shown to have evolved on multiple occasions in Australian skinks, a modification previously shown to be responsible for the Honey Badger’s iconic resistance to cobra venom. Functional testing confirmed this mode of resistance in skinks. Our findings reveal that venom resistance has evolved extensively and convergently in Australian skinks through repeated molecular adaptations of the nAChR in response to the enormous selection pressure exerted by elapid snakes subsequent to their arrival and continent-wide dispersal in Australia. These toxicological findings highlight a remarkable example of convergent evolution across vertebrates and provide insight into the adaptive significance of toxin resistance in snake–lizard ecological interactions. Full article

Background/Objectives: Most snakebite incidents in Latin America are caused by species of the Bothrops genus. Their venom induces severe local effects, against which antivenom therapy has limited efficacy. Metabolites derived from Coffea arabica have demonstrated anti-inflammatory and anticoagulant properties, suggesting their potential as therapeutic agents to inhibit the local effects induced by B. asper venom. Methods: Three enzymatic assays were performed: inhibition of the procoagulant and amidolytic activities of snake venom serine proteinases (SVSPs); inhibition of the proteolytic activity of snake venom metalloproteinases (SVMPs); and inhibition of the catalytic activity of snake venom phospholipases A₂ (PLA_2s). Additionally, molecular docking studies were conducted to propose potential inhibitory mechanisms of the metabolites chlorogenic acid, caffeine, and caffeic acid. Results: Green and roasted coffee extracts partially inhibited the enzymatic activity of SVSPs and SVMPs. Notably, the green coffee extract, at a 1:20 ratio, effectively inhibited PLA₂ activity. Among the individual metabolites tested, partial inhibition of SVSP and PLA₂ activities was observed, whereas no significant inhibition of SVMP proteolytic activity was detected. Chlorogenic acid was the most effective metabolite, significantly prolonging plasma coagulation time and achieving up to 82% inhibition at a concentration of 62.5 μM. Molecular docking analysis revealed interactions between chlorogenic acid and key active site residues of SVSP and PLA₂ enzymes from B. asper venom. Conclusions: The roasted coffee extract demonstrated the highest inhibitory effect on venom toxins, potentially due to the formation of bioactive compounds during the Maillard reaction. Molecular modeling suggests that the tested inhibitors may bind to and occupy the substrate-binding clefts of the target enzymes. These findings support further in vivo research to explore the use of plant-derived polyphenols as adjuvant therapies in the treatment of snakebite envenoming. Full article

Plant latex is a rich source of proteolytic enzymes with potential biomedical applications, particularly in hemostasis. Among them, thrombin-like enzymes (TLEs) have garnered interest in their ability to mimic thrombin by catalyzing the conversion of fibrinogen to fibrin, facilitating clot formation. While TLEs from snake venoms have been well-characterized and applied clinically, their plant-derived counterparts remain underexplored. This review critically examines the structural and functional characteristics of TLEs from plant latex, comparing them to animal-derived TLEs and evaluating their role in both procoagulant and fibrinolytic processes. Emphasis is placed on dual fibrinogenolytic and fibrinolytic activities exhibited by latex proteases, which often vary with concentration, incubation time, and protease type. In vitro coagulation assays and electrophoretic analyses are discussed as critical tools for characterizing their multifunctionality. By addressing the knowledge gaps and proposing future directions, this paper positions plant latex proteases as promising candidates for development in localized hemostatic and thrombolytic therapies. Full article

This study used all-atom molecular dynamics simulations to investigate the structural dynamics of Ves a 1, a phospholipase from Vespa affinis venom, and its interactions within a lipid membrane environment, both alone and in the presence of the inhibitor voxilaprevir. Simulations conducted over 1 $\mathsf{\mu }$s for triplicate runs demonstrated system stability and convergence of structural properties. Our findings reveal that Ves a 1 engages in dynamic interactions with the lipid bilayer, involving key regions such as its lids, catalytic triad, and auxiliary site. The presence of voxilaprevir was observed to subtly alter these membrane interaction patterns and influence the enzyme’s catalytic area, reflecting the inhibitor’s impact within its physiological context. These results emphasize the crucial role of the lipid bilayer in shaping enzyme function and highlight voxilaprevir as a promising candidate for further inhibitor development, offering vital insights for rational drug design targeting membrane-associated proteins. Full article

Ant venoms are rich sources of bioactive molecules, including peptide toxins with potent and selective activity on ion channels, which makes them valuable for pharmacological research and therapeutic development. Voltage-dependent potassium (Kv) channels, critical for regulating cellular excitability or cell cycle progression control, are targeted by a diverse array of venom-derived peptides. This study focuses on MYRTX_A4-Tb11a, a peptide from Tetramorium bicarinatum venom, which was previously shown to have a strong paralytic effect on dipteran species without cytotoxicity on insect cells. In the present study, we show that Tb11a exhibited no or low cytotoxicity toward mammalian cells either, even at high concentrations, while electrophysiological studies revealed a blockade of hKv1.3 activity. Additionally, Ta11a, an analog of Tb11a from the ant Tetramorium africanum, demonstrated similar Kv1.3 inhibitory properties. Structural analysis supports that the peptide acts on Kv1.3 channels through the functional dyad Y21-K25 and that the disulfide bridge is essential for biological activity, as reduction seems to disrupt the peptide conformation and impair the dyad. These findings highlight the importance of three-dimensional structure in channel modulation and establish Tb11a and Ta11a as promising Kv1.3 inhibitors. Future research should investigate their selectivity across additional ion channels and employ structure-function studies to further enhance their pharmacological potential. Full article

Phospholipase A1 (Ves a 1), a major toxin from Vespa affinis venom, poses significant risks to allergic individuals. Nevertheless, the epitope determinants of Ves a 1 have not been characterized. Thus, identifying its linear B-cell epitopes is crucial for understanding envenomation mechanisms. In this study, we predicted and identified B-cell epitopes EP5 and EP6 as potential candidates. EP5 formed an α-helix at the active site of Ves a 1, whereas EP6 adopted an extended loop conformation. Both synthetic peptides were synthesized and evaluated for their inhibitory effects using immune-inhibitory assays with polyclonal antibodies (pAbs) targeting both native (nVes a 1) and recombinant (rVes a 1) forms. The Ves a 1 polyclonal antibodies (pAb-nVes a 1 and pAb-Ves a 1) were produced, and their specificity binding to Ves a 1 was confirmed by Western blot. Next, ELISA inhibition assays showed that EP5 and EP6 significantly blocked pAb binding to both nVes a 1 and rVes a 1. Dot blot and Western blot assays supported these findings, particularly with stronger inhibition toward rVes a 1. Furthermore, enzymatic assays indicated that nVes a 1 and rVes a 1 retained phospholipase activity. Immunoinformatics docking showed that EP5 and EP6 specifically bind to a single-chain variable fragment antibody (scFv) targeting Naja naja PLA2. Molecular analysis revealed similar amino acid interactions to the template, suggesting effective paratope–epitope binding. These results support the potential of EP5 and EP6 for future diagnosis and therapy of V. affinis venom allergy. Full article

Animal venoms are complex biochemical secretions rich in highly potent and selective bioactive molecules, including peptides, enzymes, and small organic compounds. Once associated primarily with toxicity, these venoms are now recognized as a promising source of therapeutic agents for a wide range of medical conditions. This review provides a comprehensive analysis of the pharmacological potential of venom-derived compounds, highlighting their mechanisms of action, such as ion channel modulation, receptor targeting, and enzyme inhibition. Successful venom-derived drugs like captopril and ziconotide exemplify the translational potential of this biological arsenal. We discuss therapeutic applications in cardiovascular diseases, chronic pain, cancer, thrombosis, and infectious diseases, as well as emerging peptide candidates in clinical development. Technological advancements in omics, structural biology, and synthetic peptide engineering have significantly enhanced the discovery and optimization of venom-based therapeutics. Despite challenges related to stability, immunogenicity, and ecological sustainability, the integration of AI-driven drug discovery and personalized medicine is expected to accelerate progress in this field. By synthesizing current findings and future directions, this review underscores the transformative potential of animal venoms in modern pharmacotherapy and drug development. We also discuss current therapeutic limitations and how venom-derived compounds may address unmet needs in specific disorders. Full article

Crotoxin (CTX), the main toxin in Crotalus durissus terrificus venom, is a heterodimeric complex known for its antitumoral, anti-inflammatory, and immunomodulatory properties. In macrophages, CTX stimulates energy metabolism, pro-inflammatory cytokines, superoxide production, and lipoxin A₄ secretion while inhibiting macrophage spreading and phagocytosis. These effects are completely blocked by Boc-2, a selective formyl peptide receptors (FPRs) antagonist. Despite the correlation between FPRs and CTX-mediated effects, their involvement in mediating CTX entry into macrophages remains unclear. This study aimed to investigate the involvement of FPRs in CTX entry into monocytes and macrophages. For this, THP-1 cells were silenced for FPRs or treated with Boc-2. Results demonstrated that FPR-related signaling pathways, which influence macrophage functions such as ROS release, phagocytosis, and spreading, were reduced in FPR-silenced cells. However, even in the absence of FPRs, CTX was efficiently internalized by macrophages. These findings suggest that FPRs are essential for the immunomodulatory effects of CTX, but are not involved in CTX internalization. Full article

The venom of Bothrops jararaca (BjV) induces intense and prolonged pain, which is not alleviated by antivenom, along with hemorrhage and inflammation. In this study, we investigated the effects of the specialized pro-resolving lipid mediator (SPM) maresin 2 (MaR2) in a murine model of BjV-evoked pain and inflammation. Mice received a single intraperitoneal (i.p.) injection of MaR2 30 min before the intraplantar BjV injection. MaR2 treatment significantly attenuated mechanical (electronic aesthesiometer) and thermal (hot plate) hyperalgesia in a dose-dependent manner. Additionally, MaR2 restored the balance for the hind-paw static weight distribution. When BjV (0.01, 0.1, and 1 μg) stimulus was administered intraperitoneally, pre-treatment with MaR2 (0.3, 1, or 3 ng) ameliorated mechanical and thermal hyperalgesia in a dose-dependent manner. Moreover, MaR2 (3 ng) effectively reduced the levels of myeloperoxidase activity and cytokines (TNF-α, IL-1β, and IL-6) and superoxide anion (O₂^•−) production induced by intraplantar injection of BjV while enhancing total antioxidant levels (ABTS scavenging). For the peritonitis model induced by BjV, MaR2 pretreatment decreased leukocyte recruitment, hemorrhage, nitric oxide (NO), and O₂^•− generation and gp91phox and inducible nitric oxide synthase (iNOS) mRNA expression. In conclusion, this study presents the first evidence that MaR2 effectively mitigated BjV-induced pain, hemorrhage, and inflammation. Full article

Parasitoid venom significantly influences host physiology and development. Our previous research identified high levels of insulin-binding protein IMP-L2 in the venom of Scleroderma guani. IMP-L2 may inhibit the insulin/insulin-like growth factor signaling (IIS) cascade by competitively binding insulin-like peptides (ILPs) with insulin receptor (InR). However, how to regulate IIS transduction is unclear. We speculate that venom-derived IMP-L2 may bind ILPs to inhibit IIS transduction. Consequently, we investigated the regulation of the IIS/TOR pathway by venom-derived IMP-L2. An expression analysis of IIS/TOR pathway genes across various developmental stages of Tenebrio molitor demonstrated that this pathway governs the entire developmental process. By examining gene expression before and after parasitism, we determined that S. guani predominantly inhibits TOR pathway signaling in T. molitor post-parasitism. Bioinformatics and expression analyses revealed that IMP-L2 is critically involved in Hymenoptera insects, exhibiting high expression in the venom apparatus, and is upregulated in response to S. guani parasitism factors. Additionally, recombinant IMP-L2 was produced via eukaryotic expression. Finally, the recombinant IMP-L2 was found to inhibit the TOR and IIS/TOR signaling pathways at early (6 h) and late (24 h) stages post-injection. Knockdown of IMP-L2 in S. guani parasitized T. molitor pupae, resulting in accelerated death of T. molitor. During parasitism, S. guani may suppress host growth and development by modulating the IIS/TOR signaling pathway through venom-derived IMP-L2, potentially affecting host lifespan. Full article

Three-finger toxins (3FTxs) are the largest group of nonenzymatic toxins found in snake venoms. Among them, neurotoxins that target nicotinic acetylcholine receptors are the most well-studied ligands. In addition to the classical neurotoxins, several other new classes have been characterized for their structure, receptor subtype, and species selectivity. Here, we systematically analyzed over 700 amino acid sequences of three-finger neurotoxins that interact with nicotinic acetylcholine receptors. Based on the amino acid residue substitutions in the functional sites and structural features of various classes of neurotoxins, we have classified them into over 150 distinct subgroups. Currently, only a small number of typical examples representing these subgroups have been studied for their structure, function, and subtype selectivity. The functional site residues responsible for their interaction with specific receptor subtypes of several toxins are yet to be identified. The molecular details of each subgroup representative toxin with its target receptor will contribute towards the understanding of subtype- and/or interface-selectivity. Thus, this review will provide new impetus in the toxin research and pave the way for the design of potent, selective ligands for nicotinic acetylcholine receptors. Full article

The snakes from the genus Bothrops are responsible for most of the ophidic accidents in Brazil, and Bothrops atrox represents one of these species. Envenomation by these snakes results in systemic effects and is often associated with early mortality following snakebite incidents. The present study investigates the pharmacological properties of Bothrops atrox venom (VBA), focusing specifically on its impact on renal blood flow. Following the renal perfusion procedure, kidney tissues were processed for histopathological examination. Statistical analysis of all evaluated parameters was conducted using ANOVA and Student’s t-test, with significance set at p < 0.005. Administration of VBA resulted in a marked reduction in both perfusion pressure and renal vascular resistance. In contrast, there was a significant elevation in urinary output and glomerular filtration rate. Histological changes observed in the perfused kidneys were mild. The involvement of nitric oxide in the pressor effects of Bothrops atrox venom was not investigated in renal perfusion systems or in in vivo models. Treatment with VBA led to elevated nitrite levels in the bloodstream of the experimental animals. This effect was completely inhibited following pharmacological blockade with L-NAME. Based on these findings, we conclude that VBA alters renal function and promotes increased nitric oxide production. Full article