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Purpose of Review: Snakebite envenomation, classified as a neglected tropical disease, represents a significant global health threat, particularly in Asia and Africa, where it causes between 57,000 and 100,000 deaths annually. Envenomation by cobras, especially those of the genus Naja, contributes substantially to this burden. This review explores the complexities of cobra venom composition, its associated complications, and current treatment strategies, with a focus on venom-derived therapeutic prospects. Recent Findings: Cobra venom is a complex mixture primarily composed of proteins and peptides that exert various toxic effects, including neurotoxicity, tissue damage, and systemic complications. Antivenom therapy remains the primary treatment for envenomation, successfully mitigating critical effects such as bleeding and paralysis. Recent research, however, has revealed that certain venom-derived molecules possess therapeutic potential, opening up new possibilities for drug development. Summary: Despite the lethal nature of cobra envenomation, advances in antivenom therapy and emerging research into the medicinal properties of venom-derived molecules offer hope. This review highlights the dual nature of cobra venom—both as a source of severe pathology and as a potential reservoir for therapeutic agents—fostering the development of novel drugs. [ABSTRACT FROM AUTHOR]

Purpose: Snake venom, despite its toxicity, presents notable therapeutic potential by specifically targeting tumor cells to inhibit their proliferation or induce their apoptosis. However, with the global rise in hepatocellular carcinoma rates, new treatments are needed that move away from surgery and toxic chemotherapy. Research has revealed that snake venoms, particularly those of cobras, contain promising molecules for the treatment of cancer. Methods: Our study evaluates the toxicity (LD50) of the Moroccan cobra venom Naja haje as well as its fractions obtained by gel filtration fractionation. We also analyze their antiproliferative activity on HepG2 hepatocellular carcinoma cells. Cell viability was determined by MTT assay and the fractions that exhibited proliferation inhibitions of HepG2 cells were analyzed by mass spectrometry (LC-MS/MS). Results: Our results show that the LD50 of Naja haje venom varies depending on the route of administration, 0.69, 0.79 and 0.90 µg/g by intracerebroventricular, intravenous and intraperitoneal routes, respectively. On the other hand, the fractions, notably 1, 2, 3, 7 and 8, demonstrate significant antiproliferative activity on the HepG2 cells in vitro, and this activity is enhanced at a concentration of 50 µg/mL, highlighting their therapeutic potential. LC-MS/MS analysis of the active fractions revealed a complex molecular composition, including cytotoxins, neurotoxins, cardiotoxins, and a diverse array of peptides. Conclusions: Fractions 7 and 8 from Naja haje venom showed significant antiproliferative effects on HepG2 cells at 10 µg/mL, enhanced at 50 µg/mL. [ABSTRACT FROM AUTHOR]

Abstract Background Venoms have repeatedly evolved over 100 occasions throughout the animal tree of life, making them excellent systems for exploring convergent evolutionary novelty. Growing evidence supports that venom evolution is predominantly driven by prey or host-related selection pressures, and the expression patterns of venom glands reflect adaptive evolution. However, it remains elusive whether the evolution of expression patterns in venom glands is likewise a convergent evolution driven by their prey/host species. Results We utilized parasitoid wasps that had independently adapted to Drosophila hosts as models to investigate the convergent evolution of venom gland transcriptomes in 19 hymenopteran species spanning ~ 200 million years of evolution. Comparative transcriptome analysis reveals that the global expression patterns among the venom glands of Drosophila parasitoid wasps do not achieve higher similarity compared to non-Drosophila parasitoid wasps. Further evolutionary analyses of expression patterns at the single gene, orthogroup, and Gene Ontology (GO) term levels indicate that some orthogroups/GO terms show correlation with the Drosophila parasitoid wasps. However, these groups rarely include genes highly expressed in venom glands or putative venom genes in the Drosophila parasitoid wasps. Conclusions Our study suggests that convergent evolution may not play a predominant force shaping gene expression levels in the venom gland of the Drosophila parasitoid wasps, offering novel insights into the co-evolution between venom and prey/host.

Abstract Three-finger proteins are the most abundant toxins in the venom of Naja ashei, a snake species from the Elapidae family. This research aimed to describe the effects of varying charges of these proteins, isolated from Naja ashei venom using SEC and IEX chromatography. The study examined how differently charged three-finger toxin fractions interact with and affect neuroblastoma (SK-N-SH) and promyeloblast (HL-60) cells, as well as model Langmuir membranes and liposomes designed to mimic cellular lipid composition. Findings revealed that protein surface charges significantly impact cell survival (MTT assay), membrane damage (lactate dehydrogenase release, malondialdehyde formation), and the structural and electrochemical properties of model membranes (Langmuir membranes and zeta potential for liposomes and cancer cell lines). Results indicated that SK-N-SH cells, characterized by a higher negative charge on their cell membranes, interacted more effectively with positively charged toxins than HL-60 cells. However, the mechanism of these electrostatic interactions is complex. The research demonstrated that electrostatic and mechanical membrane modifications induced by venom proteins can significantly affect cell metabolism. Additionally, the total charge of the membrane, influenced by polar lipid components and phospholipid saturation, plays a decisive role in toxin interaction.

Abstract This study focused on developing an optimal formulation of liposomes loaded with bee venom (BV) and coated with PEG (BV-Lipo-PEG). The liposomes were characterized using dynamic light scattering, transmission electron microscopy, and Fourier transform infrared spectroscopy. Among the liposomal formulations, F3 exhibited the narrowest size distribution with a low PDI value of 193.72 ± 7.35, indicating minimal agglomeration-related issues and a more uniform size distribution. BV-Lipo-PEG demonstrated remarkable stability over 3 months when stored at 4 °C. Furthermore, the release of the drug from the liposomal formulations was found to be pH-dependent. Moreover, BV-Lipo-PEG exhibited favorable entrapment efficiencies, with values reaching 96.74 ± 1.49. The anticancer potential of the liposomal nanocarriers was evaluated through MTT assay, flow cytometry, cell cycle analysis, and real-time experiments. The functionalization of the liposomal system enhanced endocytosis. The IC50 value of BV-Lipo-PEG showed a notable decrease compared to both the free drug and BV-Lipo alone, signifying that BV-Lipo-PEG is more effective in inducing cell death in A549 cell lines. BV-Lipo-PEG exhibited a higher apoptotic rate in A549 cell lines compared to other samples. In A549 cell lines treated with BV-Lipo-PEG, the expression levels of MMP-2, MMP-9, and Cyclin E genes decreased, whereas the expression levels of Caspase3 and Caspase9 increased. These findings suggest that delivering BV via PEGylated liposomes holds significant promise for the treatment of lung cancer.

Sirithanan Charoenwikkai,1,2 Premmika Intapun,1 Mongkol Lao-Araya1 1Department of Pediatrics, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand; 2Khanu Woralaksaburi Hospital, Saen To, Khanu Woralaksaburi, Kamphaeng Phet, 62130, ThailandCorrespondence: Mongkol Lao-Araya, Division of Allergy and Clinical Immunology, Department of Pediatrics, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand, Tel +665 393 5412-15, Fax +665 393 5412, Email laoaraya@gmail.comObjective: This study aims to assess the clinical outcomes and risk factors associated with severe systemic reactions following bee stings, focusing on patients treated at Pa-Sang Community Hospital, located in Lamphun Province, Thailand, which is recognized as one of the country’s largest apicultural areas.Methods: A retrospective review was conducted, utilizing electronic medical records with ICD-10 coding, of patients treated for bee sting injuries at the Emergency Department of Pa-Sang Hospital from January 2015 to December 2019.Results: This analysis included a total of 591 bee sting events involving 533 patients. The average incidence of bee sting injuries was 31.3 per 10,000 Emergency Department visits, with 55% being male. A significant majority (86%) of events occurred outside the patients’ home area. Notably, the head or extremities (49%) were the most common anatomical sites stung. Systemic reactions were observed in 44% of cases, with 96 visits (16%) diagnosed as anaphylaxis. Epinephrine injection was administered in 77% of these cases, and fortunately, no fatal anaphylactic reactions were recorded. Protective factors for anaphylaxis and severe systemic reactions after bee stings included age less than 15 years old and stings on extremities. Conversely, having more than ten bee stings and seeking Emergency Department treatment within 60 minutes of being stung were identified as significant risk factors.Conclusion: Bee sting injuries were a common presentation at the hospital situated in the high apicultural area, and severe systemic reactions were observed. This study highlights the need for comprehensive interventions to mitigate the increased risk of bee-related accidents in communities with thriving apicultural industries.Keywords: bee sting, venom, anaphylaxis, bee keeping, Thailand

Beekeepers represent a high-allergic risk population group due to their unavoidable seasonal or persistent exposure to the elicitors of Hymenoptera venom allergy, bees in particular. A systematic literature review and meta-analysis aimed to estimate the prevalence of self-reported systemic allergic reaction to Hymenoptera venom among beekeepers worldwide.

Abstract Background Evolution of novelty is a central theme in evolutionary biology, yet studying the origins of traits with an apparently discontinuous origin remains a major challenge. Venom systems are a well-suited model for the study of this phenomenon because they capture several aspects of novelty across multiple levels of biological complexity. However, while there is some knowledge on the evolution of individual toxins, not much is known about the evolution of venom systems as a whole. One way of shedding light on the evolution of new traits is to investigate less specialised serial homologues, i.e. repeated traits in an organism that share a developmental origin. This approach can be particularly informative in animals with repetitive body segments, such as centipedes. Results Here, we investigate morphological and biochemical aspects of the defensive telopodal glandular organs borne on the posterior legs of venomous stone centipedes (Lithobiomorpha), using a multimethod approach, including behavioural observations, comparative morphology, proteomics, comparative transcriptomics and molecular phylogenetics. We show that the anterior venom system and posterior telopodal defence system are functionally convergent serial homologues, where one (telopodal defence) represents a model for the putative early evolutionary state of the other (venom). Venom glands and telopodal glandular organs appear to have evolved from the same type of epidermal gland (four-cell recto-canal type) and while the telopodal defensive secretion shares a great degree of compositional overlap with centipede venoms in general, these similarities arose predominantly through convergent recruitment of distantly related toxin-like components. Both systems are composed of elements predisposed to functional innovation across levels of biological complexity that range from proteins to glands, demonstrating clear parallels between molecular and morphological traits in the properties that facilitate the evolution of novelty. Conclusions The evolution of the lithobiomorph telopodal defence system provides indirect empirical support for the plausibility of the hypothesised evolutionary origin of the centipede venom system, which occurred through functional innovation and gradual specialisation of existing epidermal glands. Our results thus exemplify how continuous transformation and functional innovation can drive the apparent discontinuous emergence of novelties on higher levels of biological complexity.

Byline: S. M. Fatima, W. Tahir, M. Moin, H. Waheed and H. Khan Keywords: Traditional medicine;Datura alba; Anti-phospholipase A2; Anti-amylase; Antioxidant INTRODUCTION Traditional medicine (TM) is an integral part of [...]

The activation of cyclic GMP‐AMP (cGAMP) synthase (cGAS) and its adaptor, stimulator of interferon genes (STING), is known to reprogram the immunosuppressive tumor microenvironment for promoting antitumor immunity. To enhance the efficiency of cGAS‐STING pathway activation, macrophage‐selective uptake, and programmable cytosolic release are crucial for the delivery of STING agonists. However, existing polymer‐ or lipid‐based delivery systems encounter difficulty in integrating multiple functions meanwhile maintaining precise control and simple procedures. Herein, inspired by cGAS being a natural DNA sensor, a modularized DNA nanodevice agonist (DNDA) is designed that enable macrophage‐selective uptake and programmable activation of the cGAS‐STING pathway through precise self‐assembly. The resulting DNA nanodevice acts as both a nanocarrier and agonist. Upon local administration, it demonstrates the ability of macrophage‐selective uptake, endosomal escape, and cytosolic release of the cGAS‐recognizing DNA segment, leading to robust activation of the cGAS‐STING pathway and enhanced antitumor efficacy. Moreover, DNDA elicits a synergistic therapeutic effect when combined with immune checkpoint blockade. The study broadens the application of DNA nanotechnology as an immune stimulator for cGAS‐STING activation. [ABSTRACT FROM AUTHOR]

The larvae of Neuroptera are predators that feed by injecting bioactive compounds into their prey and then suctioning the fluids through modified mouthparts. We explore the evolutionary history of this feeding structure through the examination of a new fossil larva preserved in Late Cretaceous Kachin amber, which we describe as new genus and species, Electroxipheus veneficus gen et sp. nov. X-ray phase-contrast microtomography enabled us to study the anatomy of the larva in 3D, including the structure of the mouthparts and that of the venom delivery system. The specimen exhibited a unique combination of morphological traits not found in any known fossil or extant lacewing, including an unusual structure of the antenna. Phylogenetic analyses, incorporating a selection of living and fossil larval Neuroptera and enforcing maximum parsimony and Bayesian inference, identified the larva as belonging to the stem group Mantispoidea. The larva shows that the anatomy of the feeding and venom-delivery apparatus has remained unchanged in Neuroptera from the Cretaceous to the present. The morphology of the specimen suggests that it was an active predator, in contrast with the scarcely mobile, specialized relatives, like mantispids and berothids. [ABSTRACT FROM AUTHOR]

Bacteria can be utilized for cancer therapy owing to their preferential colonization at tumor sites. However, unmodified non‐pathogenic bacteria carry potential risks due to their non‐specific targeting effects, and their anti‐tumor activity is limited when used as monotherapy. In this study, a biohybrid‐engineered bacterial system comprising non‐pathogenic MG1655 bacteria modified with CDH17 nanobodies on their surface and conjugated with photosensitizer croconium (CR) molecules is developed. The resultant biohybrid bacteria can efficiently home to CDH17‐positive tumors, including gastric, pancreatic, and colorectal cancers, and significantly suppress tumor growth upon irradiation. More importantly, biohybrid bacteria‐mediated photothermal therapy (PTT) induced abundant macrophage infiltration in a syngeneic murine colorectal model. Further, that the STING pathway is activated in tumor macrophages by the released bacterial nucleic acid after PTT is revealed, leading to the production of type I interferons. The addition of CD47 nanobody but not PD‐1 antibody to the PTT regimen can eradicate the tumors and extend survival. This results indicate that bacteria endowed with tumor‐specific selectivity and coupled with photothermal payloads can serve as an innovative strategy for low‐immunogenicity cancers. This strategy can potentially reprogram the tumor microenvironment by inducing macrophage infiltration and enhancing the efficacy of immunotherapy targeting macrophages. [ABSTRACT FROM AUTHOR]

Background: Venoms have repeatedly evolved over 100 occasions throughout the animal tree of life, making them excellent systems for exploring convergent evolutionary novelty. Growing evidence supports that venom evolution is predominantly driven by prey or host-related selection pressures, and the expression patterns of venom glands reflect adaptive evolution. However, it remains elusive whether the evolution of expression patterns in venom glands is likewise a convergent evolution driven by their prey/host species. Results: We utilized parasitoid wasps that had independently adapted to Drosophila hosts as models to investigate the convergent evolution of venom gland transcriptomes in 19 hymenopteran species spanning ~ 200 million years of evolution. Comparative transcriptome analysis reveals that the global expression patterns among the venom glands of Drosophila parasitoid wasps do not achieve higher similarity compared to non-Drosophila parasitoid wasps. Further evolutionary analyses of expression patterns at the single gene, orthogroup, and Gene Ontology (GO) term levels indicate that some orthogroups/GO terms show correlation with the Drosophila parasitoid wasps. However, these groups rarely include genes highly expressed in venom glands or putative venom genes in the Drosophila parasitoid wasps. Conclusions: Our study suggests that convergent evolution may not play a predominant force shaping gene expression levels in the venom gland of the Drosophila parasitoid wasps, offering novel insights into the co-evolution between venom and prey/host. [ABSTRACT FROM AUTHOR]

Glioblastoma multiforme (GBM) is a highly aggressive and fatal primary brain tumor. The resistance of GBM to conventional treatments is attributed to factors such as the blood–brain barrier, tumor heterogeneity, and treatment-resistant stem cells. Current therapeutic efforts show limited survival benefits, emphasizing the urgent need for novel treatments. In this context, natural anti-cancer extracts and especially animal venoms have garnered attention for their potential therapeutic benefits. Bee venom in general and that of the Middle Eastern bee, Apis mellifera syriaca in particular, has been shown to have cytotoxic effects on various cancer cell types, but not glioblastoma. Therefore, this study aimed to explore the potential of A. mellifera syriaca venom as a selective anti-cancer agent for glioblastoma through in vitro and in vivo studies. Our results revealed a strong cytotoxic effect of A. mellifera syriaca venom on U87 glioblastoma cells, with an IC50 of 14.32 µg/mL using the MTT test and an IC50 of 7.49 µg/mL using the LDH test. Cells treated with the bee venom became permeable to propidium iodide without showing any signs of early apoptosis, suggesting compromised membrane integrity but not early apoptosis. In these cells, poly (ADP-ribose) polymerase (PARP) underwent proteolytic cleavage similar to that seen in necrosis. Subsequent in vivo investigations demonstrated a significant reduction in the number of U87 cells in mice following bee venom injection, accompanied by a significant increase in cells expressing caspase-3, suggesting the occurrence of cellular apoptosis. These findings highlight the potential of A. mellifera syriaca venom as a therapeutically useful tool in the search for new drug candidates against glioblastoma and give insights into the molecular mechanism through which the venom acts on cancer cells. [ABSTRACT FROM AUTHOR]

Introduction: Snakebites are acute systemic toxic diseases caused by snake venom entering the body through wounds. Failure to use antivenom immediately and difficulty in obtaining antivenoms are frequently responsible for worsening disease. Traditional Chinese medicine is commonly used to supplement and replace antivenom in treating snakebites. The Jidesheng snake pill (JDS) is a widely used traditional Chinese medicine that has achieved good clinical therapeutic effects; however, its mechanism remains unclear. Therefore, metabolomics techniques were employed to explore the pathophysiological mechanisms of JDS treatment of Agkistrodon halys (Ah) snake venompoisoned mice. Methods: The Ah group mouse model was established by intramuscular injection of Ah venom into the hind legs of the mice. The Ah venom + JDS group model was established using JDS after the affected area was treated with Ah venom. Hematoxylin and eosin (HE) staining was used to evaluate the severity of gastrocnemius injury. Quantitative polymerase chain reaction (qPCR) was utilized to detect the mRNA expression of vascular cell adhesion molecule-1 (VCAM-1), muscle-specific creatine kinase (CKM), thrombin antithrombin complex (TAT), and tumor necrosis factor-alpha (TNF-α). Gas chromatography-mass spectrometry (GC-MS) was performed with multivariate statistical analysis to provide new insights into the global metabolic profile of Ah venom-poisoned mice. Results: HE staining revealed increased red cell necrosis, local hemorrhage, and neutrophil infiltration in the Ah venom group than in the control group. Several compounds were identified, including lipids, amino acids, peptides, and organooxygen. Eighty differential metabolites were screened between the control group and the Ah venom group, and 24 were screened between the Ah venom and JDS groups. The mechanism of Ah venom poisoning in mice may involve aminoacyl-tRNA biosynthesis, various amino acid metabolism disorders, tricarboxylic acid circulation disorders, and abnormal fatty acid metabolism. JDS may reduce symptoms by affecting longchain fatty acid and amino acid metabolism and promoting nicotinamidenicotinamide metabolism. Conclusion: Our results suggest that metabolomics has huge prospects for elucidating the pathophysiology of Agkistrodon haly venom poisoning and therapeutic mechanisms of JDS. [ABSTRACT FROM AUTHOR]

Neuropteran larvae are fierce predators that use venom to attack and feed on arthropod prey. Neuropterans have adapted to diverse and sometimes extreme habitats, suggesting their venom may have evolved accordingly, but the ecology and evolution of venom deployment in different families is poorly understood. We applied spatial transcriptomics, proteomics, morphological analysis, and bioassays to investigate the venom systems in the antlion Euroleon nostras and the lacewing Chrysoperla carnea, which occupy distinct niches. Although the venom system morphology was similar in both species, we observed remarkable differences at the molecular level. E. nostras produces particularly complex venom secreted from three different glands, indicating functional compartmentalization. Furthermore, E. nostras venom and digestive tissues were devoid of bacteria, strongly suggesting that all venom proteins are of insect origin rather than the products of bacterial symbionts. We identified several toxins exclusive to E. nostras venom, including phospholipase A2 and several undescribed proteins with no homologs in the C. carnea genome. The compositional differences have significant ecological implications because only antlion venom conferred insecticidal activity, indicating its use for the immobilization of large prey. Our results indicate that molecular venom evolution plays a role in the adaptation of antlions to their unique ecological niche. A combination of methods excludes the contribution of bacteria to venom production in predacious antlions and reveals differences in neuropteran venom compositions and activities reflecting the insects' distinct ecological niches. [ABSTRACT FROM AUTHOR]

Three-finger proteins are the most abundant toxins in the venom of Naja ashei, a snake species from the Elapidae family. This research aimed to describe the effects of varying charges of these proteins, isolated from Naja ashei venom using SEC and IEX chromatography. The study examined how differently charged three-finger toxin fractions interact with and affect neuroblastoma (SK-N-SH) and promyeloblast (HL-60) cells, as well as model Langmuir membranes and liposomes designed to mimic cellular lipid composition. Findings revealed that protein surface charges significantly impact cell survival (MTT assay), membrane damage (lactate dehydrogenase release, malondialdehyde formation), and the structural and electrochemical properties of model membranes (Langmuir membranes and zeta potential for liposomes and cancer cell lines). Results indicated that SK-N-SH cells, characterized by a higher negative charge on their cell membranes, interacted more effectively with positively charged toxins than HL-60 cells. However, the mechanism of these electrostatic interactions is complex. The research demonstrated that electrostatic and mechanical membrane modifications induced by venom proteins can significantly affect cell metabolism. Additionally, the total charge of the membrane, influenced by polar lipid components and phospholipid saturation, plays a decisive role in toxin interaction. [ABSTRACT FROM AUTHOR]

Introduction: Melanoma, a highly aggressive skin cancer originating in melanocytes, poses a significant threat due to its metastatic potential. While progress has been made in treating melanoma with targeted therapies and immunotherapies, challenges persist. Crotoxin (CTX), the principal toxin in Crotalus durissus terrificus snake venom, exhibits various biological activities, including anti-tumoral effects across multiple cancers. However, its clinical use is limited by toxicity. Thus, exploring alternatives to mitigate adverse effects is crucial. Methods and Results: This study investigates the antitumoral potential of CTX in its native and in a detoxified form, in melanoma cells. Firstly, we demonstrated that detoxified CTX presented reduced phospholipase activity. Both forms proved to be more cytotoxic to SK-MEL-28 and MeWo melanoma cells than nontumoral cells. In SK-MEL-28 cells, where cytotoxic effects were more pronounced, native and detoxified CTX induced increased necrosis and apoptosis rates. We also confirmed the apoptosis death demonstrated by the activation of caspase-3 and 7, and the formation of apoptotic bodies. Furthermore, both CTX caused cell cycle arrest at the G2/M phase, interfering with melanoma cell proliferation. Cell migration and invasion were also suppressed by both CTX. These results confirm the antitumoral potential of CTX. Discussion: The maintenance of the antiproliferative effects in the detoxified version, with reduced enzymatic activity often liked to harm effects, supports further studies to identify active parts of the molecule responsible for the interesting effects without causing substantial toxic events, contributing to the future use of CTX-derived drugs with safety and efficacy. [ABSTRACT FROM AUTHOR]

Background: Snakebite envenomation is a critical public health issue in rural North Karnataka, India. This study aimed to characterize snakebite envenomation cases, focusing on incidence, clinical features, laboratory findings including coagulation parameters, and outcomes associated with Disseminated Intravascular Coagulation (DIC). Methods: A retrospective observational study analyzed data from 218 patients admitted for snakebite envenomation at PRRASAD HOSPITAL ATHANI between January 2022 and October 2023. Data on demographics, clinical presentation, laboratory investigations, treatment received, and outcomes were collected and analyzed. Results: Local pain (100%) and swelling (80%) were the most frequent presentations. Systemic signs like hematuria, oliguria, ptosis, and respiratory difficulty were less common. Deranged coagulation profiles were observed in a significant proportion of patients, with 36.7% developing DIC. Anti-snake venom (ASV) was administered to 70% of patients, with an average dose of 15- 20 vials. All patients survived. Conclusion: Snakebite envenomation in rural North Karnataka presents primarily with local symptoms. Coagulation parameters are valuable for assessing severity, with DIC being a significant complication. ASV appears beneficial, but limitations exist regarding antivenom type selection and supportive therapies due to the study's retrospective nature. Further prospective studies with larger sample sizes are warranted to optimize snakebite management in this region. [ABSTRACT FROM AUTHOR]

Naja atra, the Chinese cobra, is a major cause of snake envenomation in Asia, causing hundreds of thousands of clinical incidents annually. The current treatment, horse serum-derived antivenom, has unpredictable side effects and presents manufacturing challenges. This study focused on developing new-generation snake venom antidotes by using microbial phage display technology to derive nanobodies from an alpaca immunized with attenuated N. atra venom. Following confirmation of the immune response in the alpaca, we amplified VHH genes from isolated peripheral blood mononuclear cells and constructed a phage display VHH library of 1.0 × 107 transformants. After four rounds of biopanning, the enriched phages exhibited increased binding activity to N. atra venom. Four nanobody clones with high binding affinities were selected: aNAH1, aNAH6, aNAH7, and aNAH9. Specificity testing against venom from various snake species, including two Southeast Asian cobra species, revealed nanobodies specific to the genus Naja. An in vivo mouse venom neutralization assay demonstrated that all nanobodies prolonged mouse survival and aNAH6 protected 66.6% of the mice from the lethal dosage. These findings highlight the potential of phage display-derived nanobodies as valuable antidotes for N. atra venom, laying the groundwork for future applications in snakebite treatment. [ABSTRACT FROM AUTHOR]

Gene duplication followed by nucleotide differentiation is one of the simplest mechanisms to develop new functions for genes. However, the evolutionary processes underlying the divergence of multigene families remain controversial. We used multigene families found within the diversity of toxic proteins in centipede venom to test two hypotheses related to venom evolution: the two-speed mode of venom evolution and the rapid accumulation of variation in exposed residues (RAVER) model. The two-speed mode of venom evolution proposes that different types of selection impact ancient and younger venomous lineages with negative selection being the predominant form in ancient lineages and positive selection being the dominant form in younger lineages. The RAVER hypothesis proposes that, instead of different types of selection acting on different ages of venomous lineages, the different types of selection will selectively contribute to amino acid variation based on whether the residue is exposed to the solvent where it can potentially interact directly with toxin targets. This hypothesis parallels the longstanding understanding of protein evolution that suggests that residues found within the structural or active regions of the protein will be under negative or purifying selection, and residues that do not form part of these areas will be more prone to positive selection. To test these two hypotheses, we compared the venom of 26 centipedes from the order Scolopendromorpha from six currently recognized species from across North America using both transcriptomics and proteomics. We first estimated their phylogenetic relationships and uncovered paraphyly among the genus Scolopendra and evidence for cryptic diversity among currently recognized species. Using our phylogeny, we then characterized the diverse venom components from across the identified clades using a combination of transcriptomics and proteomics. We conducted selection-based analyses in the context of predicted three-dimensional properties of the venom proteins and found support for both hypotheses. Consistent with the two-speed hypothesis, we found a prevalence of negative selection across all proteins. Consistent with the RAVER hypothesis, we found evidence of positive selection on solvent-exposed residues, with structural and less-exposed residues showing stronger signal for negative selection. Through the use of phylogenetics, transcriptomics, proteomics, and selection-based analyses, we were able to describe the evolution of venom from an ancient venomous lineage and support principles of protein evolution that directly relate to multigene family evolution. [ABSTRACT FROM AUTHOR]

• We study the two-player repeated game where players can choose to be spite or not. • We investigate the case where players lack knowledge of their opponent's actions. • Evolution of spite is likely to occur when players exhibit persistence. Social behavior is divided into four types: altruism, spite, mutualism, and selfishness. The former two are costly to the actor; therefore, from the perspective of natural selection, their existence can be regarded as mysterious. One potential setup which encourages the evolution of altruism and spite is repeated interaction. Players can behave conditionally based on their opponent's previous actions in the repeated interaction. On the one hand, the retaliatory strategy (who behaves altruistically when their opponent behaved altruistically and behaves non-altruistically when the opponent player behaved non-altruistically) is likely to evolve when players choose altruistic or selfish behavior in each round. On the other hand, the anti-retaliatory strategy (who is spiteful when the opponent was not spiteful and is not spiteful when the opponent player was spiteful) is likely to evolve when players opt for spiteful or mutualistic behavior in each round. These successful conditional behaviors can be favored by natural selection. Here, we notice that information on opponent players' actions is not always available. When there is no such information, players cannot determine their behavior according to their opponent's action. By investigating the case of altruism, a previous study (Kurokawa, 2017, Mathematical Biosciences, 286, 94–103) found that persistent altruistic strategies, which choose the same action as the own previous action, are favored by natural selection. How, then, should a spiteful conditional strategy behave when the player does not know what their opponent did? By studying the repeated game, we find that persistent spiteful strategies, which choose the same action as the own previous action, are favored by natural selection. Altruism and spite differ concerning whether retaliatory or anti-retaliatory strategies are favored by natural selection; however, they are identical concerning whether persistent strategies are favored by natural selection. [ABSTRACT FROM AUTHOR]

Worldwide, it is estimated that there are 1.8 to 2.7 million cases of envenoming caused by snakebites. Snake venom is a complex mixture of protein toxins, lipids, small molecules, and salts, with the proteins typically responsible for causing pathology in snakebite victims. For their chemical characterization and identification, analytical methods are required. Reversed-phase liquid chromatography coupled with electrospray ionization mass spectrometry (RP-LC-ESI-MS) is a widely used technique due to its ease of use, sensitivity, and ability to be directly coupled after LC separation. This method allows for the efficient separation of complex mixtures and sensitive detection of analytes. On the other hand, matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is also sometimes used, and though it typically requires additional sample preparation steps, it offers desirable suitability for the analysis of larger biomolecules. In this study, seven medically important viperid snake venoms were separated into their respective venom toxins and measured by ESI-MS. In parallel, using nanofractionation analytics, post-column high-resolution fractionation was used to collect the eluting toxins for further processing for MALDI-MS analysis. Our comparative results showed that the deconvoluted snake venom toxin masses were observed with good sensitivity from both ESI-MS and MALDI-MS approaches and presented overlap in the toxin masses recovered (between 25% and 57%, depending on the venom analyzed). The mass range of the toxins detected in high abundance was between 4 and 28 kDa. In total, 39 masses were found in both the ESI-MS and/or MALDI-MS analyses, with most being between 5 and 9 kDa (46%), 13 and 15 kDa (38%), and 24 and 28 kDa (13%) in size. Next to the post-column MS analyses, additional coagulation bioassaying was performed to demonstrate the parallel post-column assessment of venom activity in the workflow. Most nanofractionated venoms exhibited anticoagulant activity, with three venoms additionally exhibiting toxins with clear procoagulant activity (Bothrops asper, Crotalus atrox, and Daboia russelii) observed post-column. The results of this study highlight the complementarity of ESI-MS and MALDI-MS approaches for characterizing snake venom toxins and provide a complementary overview of defined toxin masses found in a diversity of viper snake venoms. [ABSTRACT FROM AUTHOR]

Snake venoms are cocktails of biologically active molecules that have evolved to immobilize prey, but can also induce a severe pathology in humans that are bitten. While animal-derived polyclonal antivenoms are the primary treatment for snakebites, they often have limitations in efficacy and can cause severe adverse side effects. Building on recent efforts to develop improved antivenoms, notably through monoclonal antibodies, requires a comprehensive understanding of venom toxins. Among these toxins, snake venom metalloproteinases (SVMPs) play a pivotal role, particularly in viper envenomation, causing tissue damage, hemorrhage and coagulation disruption. One of the current challenges in the development of neutralizing monoclonal antibodies against SVMPs is the large size of the protein and the lack of existing knowledge of neutralizing epitopes. Here, we screened a synthetic human antibody library to isolate monoclonal antibodies against an SVMP from saw-scaled viper (genus Echis) venom. Upon characterization, several antibodies were identified that effectively blocked SVMP-mediated prothrombin activation. Cryo-electron microscopy revealed the structural basis of antibody-mediated neutralization, pinpointing the non-catalytic cysteine-rich domain of SVMPs as a crucial target. These findings emphasize the importance of understanding the molecular mechanisms of SVMPs to counter their toxic effects, thus advancing the development of more effective antivenoms. [ABSTRACT FROM AUTHOR]

Venomous marine gastropods of the superfamily Conoidea possess a rich arsenal of toxins, including neuroactive toxins. Venom adaptations might have played a fundamental role in the radiation of conoideans; nevertheless, there is still no knowledge about the venom of the most diversified family of the group: Raphitomidae Bellardi, 1875. In this study, transcriptomes were produced from the carcase, salivary glands, and proximal and distal venom ducts of the northeastern Atlantic species Raphitoma purpurea (Montagu, 1803). Using a gut barcoding approach, we were also able to report, for the first time, molecular evidence of a vermivorous diet for the genus. Transcriptomic analyses revealed over a hundred putative venom components (PVC), including 69 neurotoxins. Twenty novel toxin families, including some with high levels of expansion, were discovered. No significant difference was observed between the distal and proximal venom duct secretions. Peptides related to cone snail toxins (Cerm06, Pgam02, and turritoxin) and other venom-related proteins (disulfide isomerase and elevenin) were retrieved from the salivary glands. These salivary venom components may constitute ancestral adaptations for venom production in conoideans. Although often neglected, salivary gland secretions are of extreme importance for understanding the evolutionary history of conoidean venom. [ABSTRACT FROM AUTHOR]

Ananteris is a scorpion genus that inhabits dry and seasonal areas of South and Central America. It is located in a distinctive morpho-group of Buthids, the 'Ananteris group', which also includes species distributed in the Old World. Because of the lack of information on venom composition, the study of Ananteris species could have biological and medical relevance. We conducted a venomics analysis of Ananteris platnicki, a tiny scorpion that inhabits Panama and Costa Rica, which shows the presence of putative toxins targeting ion channels, as well as proteins with similarity to hyaluronidases, proteinases, phospholipases A2, members of the CAP-domain family, and hemocyanins, among others. Venom proteolytic and hyaluronidase activities were corroborated. The determination of the primary sequences carried out by mass spectrometry evidences that several peptides are similar to the toxins present in venoms from Old World scorpion genera such as Mesobuthus, Lychas, and Isometrus, but others present in Tityus and Centruroides toxins. Even when this venom displays the characteristic protein families found in all Buthids, with a predominance of putative Na+-channel toxins and proteinases, some identified partial sequences are not common in venoms of the New World species, suggesting its differentiation into a distinctive group separated from other Buthids. [ABSTRACT FROM AUTHOR]

Venoms are a complex cocktail of potent biomolecules and are present in many animal lineages. Owed to their translational potential in biomedicine, agriculture and industrial applications, they have been targeted by several biodiscovery programs in the past. That said, many venomous animals are relatively small and deliver minuscule venom yields. Thus, the most commonly employed activity-guided biodiscovery pipeline cannot be applied effectively. Cell-free protein production may represent an attractive tool to produce selected venom components at high speed and without the creation of genetically modified organisms, promising rapid and highly efficient access to biomolecules for bioactivity studies. However, these methods have only sporadically been used in venom research and their potential remains to be established. Here, we explore the ability of a prokaryote-based cell-free system to produce a range of venom toxins of different types and from various source organisms. We show that only a very limited number of toxins could be expressed in small amounts. Paired with known problems to facilitate correct folding, our preliminary investigation underpins that venom-tailored cell-free systems probably need to be developed before this technology can be employed effectively in venom biodiscovery. [ABSTRACT FROM AUTHOR]

Scorpions, a seemingly primitive, stinging arthropod taxa, are known to exhibit marked diversity in their venom components. These venoms are known for their human pathology, but they are also important as models for therapeutic and drug development applications. In this study, we report a high-quality genome assembly and annotation of the striped bark scorpion, Centruroides vittatus , created with several shotgun libraries. The final assembly is 760 Mb in size, with a BUSCO score of 97.8%, a 30.85% GC, and an N50 of 2.35 Mb. We estimated 36,189 proteins with 37.32% assigned to Gene Ontology (GO) terms in our GO annotation analysis. We mapped venom toxin genes to 18 contigs and 2 scaffolds. We were also able to identify expression differences between venom gland (telson) and body tissue (carapace) with 19 sodium toxin and 14 potassium toxin genes to 18 contigs and 2 scaffolds. This assembly, along with our transcriptomic data, provides further data to investigate scorpion venom genomics. [ABSTRACT FROM AUTHOR]

Venom systems are complex traits that have independently emerged multiple times in diverse plant and animal phyla. Within each venomous lineage there typically exists interspecific variation in venom composition where several factors have been proposed as drivers of variation, including phylogeny and diet. Understanding these factors is of broad biological interest and has implications for the development of antivenom therapies and venom-based drug discovery. Because of their high species richness and the presence of several major evolutionary prey shifts, venomous marine cone snails (genus Conus) provide an ideal system to investigate drivers of interspecific venom variation. Here, by analyzing the venom gland expression profiles of ∼3,000 toxin genes from 42 species of cone snail, we elucidate the role of prey-specific selection pressures in shaping venom variation. By analyzing overall venom composition and individual toxin structures, we demonstrate that the shifts from vermivory to piscivory in Conus are complemented by distinct changes in venom composition independent of phylogeny. In vivo injections of venom from piscivorous cone snails in fish further showed a higher potency compared with venom of nonpiscivores demonstrating a selective advantage. Together, our findings provide compelling evidence for the role of prey shifts in directing the venom composition of cone snails and expand our understanding of the mechanisms of venom variation and diversification. [ABSTRACT FROM AUTHOR]

Scorpions are predatory arachnids whose venomous sting primarily affects people in tropical and subtropical regions. Most scorpion stings can only cause localized pain without severe envenomation. Less than one-third of the stings cause systemic envenoming and possibly lead to death. About 350,000 scorpion stings in Northern Africa are recorded yearly, resulting in about 810 deaths. In Eastern/Southern Africa, there are about 79,000 stings recorded yearly, resulting in 245 deaths. Farmers and those living in poverty-stricken areas are among the most vulnerable to getting stung by scorpions. However, compared to adults, children are at greater risk of severe envenomation. Scorpion venom is made up of complex mixtures dominated by peptides and proteins that confer its potency and toxicity. These venom toxins have intra- and interspecies variations associated with the scorpion's habitat, sex, diet, and age. These variations alter the activity of antivenoms used to treat scorpion sting envenomation. Thus, the study of the proteome composition of medically important scorpion venoms needs to be scaled up along their geographical distribution and contributions to envenomation in Southern and Northern Africa. This will help the production of safer, more effective, and broad-spectrum antivenoms within these regions. Here, we review the clinical implications of scorpion sting envenomation in Southern and Northern Africa. We further highlight the compositions of scorpion venoms and tools used in scorpion venomics. We discuss current antivenoms used against scorpion sting envenomation and suggestions for future production of better antivenoms or alternatives. Finally, we discuss the therapeutic properties of scorpion venom. [ABSTRACT FROM AUTHOR]

Background: Snake venoms can exhibit remarkable inter- and intraspecific variation. While diverse ecological and environmental factors are theorised to explain this variation, only a handful of studies have attempted to unravel their precise roles. This knowledge gap not only impedes our understanding of venom evolution but may also have dire consequences on snakebite treatment. To address this shortcoming, we investigated the evolutionary ecology of venoms of Russell's viper (Daboia russelii) and spectacled cobra (Naja naja), India's two clinically most important snakes responsible for an alarming number of human deaths and disabilities. Methodology: Several individuals (n = 226) of D. russelii and N. naja belonging to multiple clutches (n = 9) and their mothers were maintained in captivity to source ontogenetic stage-specific venoms. Using various in vitro and in vivo assays, we assessed the significance of prey, ontogeny and sex in driving venom composition, function, and potency. Results: Considerable ontogenetic shifts in venom profiles were observed in D. russelii, with the venoms of newborns being many times as potent as juveniles and adults against mammalian (2.3–2.5 ×) and reptilian (2–10 ×) prey. This is the first documentation of the ontogenetic shift in viperine snakes. In stark contrast, N. naja, which shares a biogeographic distribution similar to D. russelii, deployed identical biochemical cocktails across development. Furthermore, the binding kinetics of cobra venom toxins against synthetic target receptors from various prey and predators shed light on the evolutionary arms race. Conclusions: Our findings, therefore, provide fascinating insights into the roles of ecology and life history traits in shaping snake venoms. [ABSTRACT FROM AUTHOR]

Background: The identification of novel toxins from overlooked and taxonomically exceptional species bears potential for various pharmacological applications. The remipede Xibalbanus tulumensis, an underwater cave-dwelling crustacean, is the only crustacean for which a venom system has been described. Its venom contains several xibalbin peptides that have an inhibitor cysteine knot (ICK) scaffold. Results: Our screenings revealed that all tested xibalbin variants particularly inhibit potassium channels. Xib1 and xib13 with their eight-cysteine domain similar to spider knottins also inhibit voltage-gated sodium channels. No activity was noted on calcium channels. Expanding the functional testing, we demonstrate that xib1 and xib13 increase PKA-II and Erk1/2 sensitization signaling in nociceptive neurons, which may initiate pain sensitization. Our phylogenetic analysis suggests that xib13 either originates from the common ancestor of pancrustaceans or earlier while xib1 is more restricted to remipedes. The ten-cysteine scaffolded xib2 emerged from xib1, a result that is supported by our phylogenetic and machine learning-based analyses. Conclusions: Our functional characterization of synthesized variants of xib1, xib2, and xib13 elucidates their potential as inhibitors of potassium channels in mammalian systems. The specific interaction of xib2 with Kv1.6 channels, which are relevant to treating variants of epilepsy, shows potential for further studies. At higher concentrations, xib1 and xib13 activate the kinases PKA-II and ERK1/2 in mammalian sensory neurons, suggesting pain sensitization and potential applications related to pain research and therapy. While tested insect channels suggest that all probably act as neurotoxins, the biological function of xib1, xib2, and xib13 requires further elucidation. A novel finding on their evolutionary origin is the apparent emergence of X. tulumensis-specific xib2 from xib1. Our study is an important cornerstone for future studies to untangle the origin and function of these enigmatic proteins as important components of remipede but also other pancrustacean and arthropod venoms. [ABSTRACT FROM AUTHOR]

This study focused on developing an optimal formulation of liposomes loaded with bee venom (BV) and coated with PEG (BV-Lipo-PEG). The liposomes were characterized using dynamic light scattering, transmission electron microscopy, and Fourier transform infrared spectroscopy. Among the liposomal formulations, F3 exhibited the narrowest size distribution with a low PDI value of 193.72 ± 7.35, indicating minimal agglomeration-related issues and a more uniform size distribution. BV-Lipo-PEG demonstrated remarkable stability over 3 months when stored at 4 °C. Furthermore, the release of the drug from the liposomal formulations was found to be pH-dependent. Moreover, BV-Lipo-PEG exhibited favorable entrapment efficiencies, with values reaching 96.74 ± 1.49. The anticancer potential of the liposomal nanocarriers was evaluated through MTT assay, flow cytometry, cell cycle analysis, and real-time experiments. The functionalization of the liposomal system enhanced endocytosis. The IC50 value of BV-Lipo-PEG showed a notable decrease compared to both the free drug and BV-Lipo alone, signifying that BV-Lipo-PEG is more effective in inducing cell death in A549 cell lines. BV-Lipo-PEG exhibited a higher apoptotic rate in A549 cell lines compared to other samples. In A549 cell lines treated with BV-Lipo-PEG, the expression levels of MMP-2, MMP-9, and Cyclin E genes decreased, whereas the expression levels of Caspase3 and Caspase9 increased. These findings suggest that delivering BV via PEGylated liposomes holds significant promise for the treatment of lung cancer. [ABSTRACT FROM AUTHOR]

Lepidopterism, a skin inflammation condition caused by direct or airborne exposure to irritating hairs (setae) from processionary caterpillars, is becoming a significant public health concern. Recent outbreaks of the oak processionary caterpillar (Thaumetopoea processionea) have caused noteworthy health and economic consequences, with a rising frequency expected in the future, exacerbated by global warming promoting the survival of the caterpillar. Current medical treatments focus on symptom relief due to the lack of an effective therapy. While the source is known, understanding the precise causes of symptoms remain incomplete understood. In this study, we employed an advanced method to extract venom from the setae and identify the venom components through high-quality de novo transcriptomics, venom proteomics, and bioinformatic analysis. A total of 171 venom components were identified, including allergens, odorant binding proteins, small peptides, enzymes, enzyme inhibitors, and chitin biosynthesis products, potentially responsible for inflammatory and allergic reactions. This work presents the first comprehensive proteotranscriptomic database of T. processionea, contributing to understanding the complexity of lepidopterism. Furthermore, these findings hold promise for advancing therapeutic approaches to mitigate the global health impact of T. processionea and related caterpillars. [ABSTRACT FROM AUTHOR]

We report Bungarus suzhenae Chen, Shi, Vogel, Ding & Shi, 2021 and Ovophis zayuensis (Jiang, 1977) for the first time from India. Specimens of B. suzhenae and O. zayuensis were collected during our field surveys in north (Arunachal Pradesh) and south (Nagaland-Manipur border) of the river Brahmaputra. Species identity was supported by partial cytochrome b (cyt b), and 16s mitochondrial gene. We provide a detailed morphological description and a key to the two genera of this region. This report extends the westernmost distribution of B. suzhenae by ca. 300 km from Myanmar, and the southernmost range of O. zayuensis by 170 km from Tibet. Until now eight species of Bungarus and only one Ovophis species have been reported from India. Ovophis species are recently reported to be medically important venomous snakes whose venom properties have not been investigated in depth. [ABSTRACT FROM AUTHOR]

Understanding how environmental factors affect the performance of predators can provide profound insights into predator–prey interactions from evolutionary and ecological perspectives and the global distributional patterns of each taxon. Almost all venomous predators are ectotherms, with muscle contraction properties depending on temperature. For predators having venom transportation systems driven by muscle contraction, temperature may have quite large effects on envenomation performance for prey subjugation. Here, we used videography and enzyme-linked immunosorbent assay to examine thermal effects on envenomation kinematics and venom expenditure in predatory strikes of a venomous snake, the Mamushi Gloydius blomhoffii, to its main rodent prey at various body temperatures under both field and laboratory experimental conditions. Unexpectedly, we found that the thermal effects on envenomation performance are limited over nearly the entire ecologically relevant range of temperature (from 13.2°C to 26.2°C). Although temperature statistically significantly affected the mass of venom injected under field conditions, temperature explained only a minor proportion of the variation in venom expenditure. These findings suggest that the Mamushi is able to maintain prey subjugation performance across a wide range of temperatures, which is highly advantageous for ectothermic predators. Further studies should examine the underlying mechanisms of the limited thermal effects and their ubiquity across venomous predators. [ABSTRACT FROM AUTHOR]

Venom production has evolved independently many times in the animal kingdom, although it is rare among mammals. Venomous shrews produce venom in their submandibular salivary glands and use it for food acquisition. Only a few toxins have been identified in shrew venoms thus far, and their modes of action require investigation. The biological and molecular processes relating to venom production and gland functioning also remain unknown. To address this gap, we investigated protein content in extracts from venom glands of two shrew species, Neomys fodiens and Sorex araneus, and interpreted their biological functions. Applying a proteomic approach coupled with Gene Ontology enrichment analysis, we identified 313 and 187 putative proteins in venom glands of N. fodiens and S. araneus, respectively. A search of the UniProt database revealed that most of the proteins found in both shrew species were involved in metabolic processes and stress response, while GO enrichment analysis revealed more stress-related proteins in the glands of S. araneus. Molecules that regulate molecule synthesis, cell cycles, and cell divisions are necessary to enable venom regeneration and ensure its effectiveness in predation and food hoarding. The presence of proteins involved in stress response may be the result of shrews' high metabolic rate and the costs of venom replenishment. Some proteins are likely to promote toxin spreading during envenomation and, due to their proteolytic action, reinforce venom toxicity. Finally, finding numerous proteins involved in immune response suggests a potential role of shrew venom gland secretions in protection against pathogens. These findings open up new perspectives for studying biological functions of molecules from shrew venom glands and extend our knowledge on the functioning of eulipotyphlan venom systems. Because the majority of existing and putative venomous mammals use oral venom systems to inject venom into target species, the methods presented here provide a promising avenue for confirming or discovering new taxa of venomous mammals. [ABSTRACT FROM AUTHOR]

Snakebites affect about 1.8 million people annually. The current standard of care involves antibody-based antivenoms, which can be difficult to access and are generally not effective against local tissue injury, the primary cause of morbidity. Here, we used a pooled whole-genome CRISPR knockout screen to define human genes that, when targeted, modify cell responses to spitting cobra venoms. A large portion of modifying genes that conferred resistance to venom cytotoxicity was found to control proteoglycan biosynthesis, including EXT1, B4GALT7, EXT2, EXTL3, XYLT2, NDST1, and SLC35B2, which we validated independently. This finding suggested heparinoids as possible inhibitors. Heparinoids prevented venom cytotoxicity through binding to three-finger cytotoxins, and the US Food and Drug Administration–approved heparinoid tinzaparin was found to reduce tissue damage in mice when given via a medically relevant route and dose. Overall, our systematic molecular dissection of cobra venom cytotoxicity provides insight into how we can better treat cobra snakebite envenoming. Editor's summary: Snakebite is considered a neglected tropical disease by the World Health Organization, and although antibody-based antivenoms exist, they are species specific, are expensive, and require cold storage as well as intravenous administration in a health care setting. Here, Du and colleagues conducted a whole-genome CRISPR knockout screen to identify genes required for spitting cobra venom cytotoxicity. This screen highlighted genes involved in proteoglycan biosynthesis, suggesting that heparinoids could potentially block spitting cobra venom cytotoxicity. The heparinoid tinzaparin, given subcutaneously at the time of intradermal venom injection, effectively reduced the size of the resulting dermonecrotic lesions in mice, supporting the further evaluation of this drug for the treatment of local tissue damage from spitting cobra envenoming. —Melissa L. Norton [ABSTRACT FROM AUTHOR]

ABSTRACT Venom represents a key adaptation of many venomous predators, allowing them to immobilise prey quickly through chemical rather than physical warfare. Evolutionary arms races between prey and a predator are believed to be the main factor influencing the potency and composition of predatory venoms. Predators with narrowly restricted diets are expected to evolve specifically potent venom towards their focal prey, with lower efficacy on alternative prey. Here, we evaluate hypotheses on the evolution of prey‐specific venom, focusing on the effect of restricted diet, prey defences, and prey resistance. Prey specificity as a potential evolutionary dead end is also discussed. We then provide an overview of the current knowledge on venom prey specificity, with emphasis on snakes, cone snails, and spiders. As the current evidence for venom prey specificity is still quite limited, we also overview the best approaches and methods for its investigation and provide a brief summary of potential model groups. Finally, possible applications of prey‐specific toxins are discussed. [ABSTRACT FROM AUTHOR]

Snake venoms constitute a complex blend of proteins and peptides, with their toxicity and pharmacological effects varying depending on their geographic origin. Naja haje, a venomous snake of significant medical importance in regions like Morocco and North Africa, can inflict severe pain, swelling, and neurotoxic symptoms upon biting. Without prompt medical intervention, these symptoms can rapidly worsen, potentially leading to fatal outcomes. Understanding the venom’s components is crucial for developing effective antivenom therapies. Specific antibodies that target the venom’s toxic elements are essential for neutralising its activity. Therefore, we conducted a proteomic analysis of these elements within Naja haje venom using gel filtration, HPLC, and mass spectrometry. Our findings identified eight fractions, among which fractions 5 and 6 exhibited notable toxicity, with fraction 5 resulting in mortality. Furthermore, we observed a prevalence of 3FTx, a diverse component in Naja venom, alongside short-chain neurotoxins such as short neurotoxin, cytotoxin, and muscarinic toxin-like proteins. Recognising these harmful elements is crucial for developing precise antivenom treatments. This investigation represents the first proteomic analysis of toxic fractions from Naja haje venom in Morocco, providing valuable insights into venom composition and aiding in the development of targeted therapies. [ABSTRACT FROM AUTHOR]

Our goal in this study is to provide quantitative and qualitative data for proper treatment planning in patients with multiple cutaneous computerized tomographic angiography with peripheral artery disease, to detect the spread of peripheral artery disease in the lower extremities, and to detect the density and types of collateral pathways in aortoiliac occlusive diseases. [ABSTRACT FROM AUTHOR]

Introduction. The proline-rich decapeptide 10c (Bj-PRO-10c; ENWPHPQIPP) from the Bothrops jararaca snake modulates argininosuccinate synthetase (AsS) activity to stimulate L-arginine metabolite production and neuroprotection in the SH-SY5Y cell line. The relationships between structure, interactions with AsS, and neuroprotection are little known. We evaluated the neuroprotective effects of Bj-PRO-10c and three other PROs (Bn-PRO-10a, Bn-PRO-10c > Bn-PRO-10a-MK > Bn-PRO-10a. The structure of PROs and their correlations with enzyme activity revealed that histidine (H5) and glutamine (Q7) in Bj-PRO-10c potentiated their affinity for AsS. Conclusions. Our investigation provides the first insights into the structure and molecular interactions of PROs with AsS, which could possibly further their neuropharmacological applications. [ABSTRACT FROM AUTHOR]

Genome-wide information has so far been unavailable for ribbon worms of the clade Hoplonemertea, the most species-rich class within the phylum Nemertea. While species within Pilidiophora, the sister clade of Hoplonemertea, possess a pilidium larval stage and lack stylets on their proboscis, Hoplonemertea species have a planuliform larva and are armed with stylets employed for the injection of toxins into their prey. To further compare these developmental, physiological, and behavioral differences from a genomic perspective, the availability of a reference genome for a Hoplonemertea species is crucial. Such data will be highly useful for future investigations toward a better understanding of molecular ecology, venom evolution, and regeneration not only in Nemertea but also in other marine invertebrate phyla. To this end, we herein present the annotated chromosome-level genome assembly for Emplectonema gracile (Nemertea; Hoplonemertea; Monostilifera; Emplectonematidae), an easily collected nemertean well suited for laboratory experimentation. The genome has an assembly size of 157.9 Mb. Hi-C scaffolding yielded chromosome-level scaffolds, with a scaffold N50 of 10.0 Mb and a score of 95.1% for complete BUSCO genes found as a single copy. Annotation predicted 20,684 protein-coding genes. The high-quality reference genome reaches an Earth BioGenome standard level of 7.C.Q50. [ABSTRACT FROM AUTHOR]

Understanding and predicting the relationships between genotype and phenotype is often challenging, largely due to the complex nature of eukaryotic gene regulation. A step towards this goal is to map how phenotypic diversity evolves through genomic changes that modify gene regulatory interactions. Using the Prairie Rattlesnake (Crotalus viridis) and related species, we integrate mRNA-seq, proteomic, ATAC-seq and whole-genome resequencing data to understand how specific evolutionary modifications to gene regulatory network components produce differences in venom gene expression. Through comparisons within and between species, we find a remarkably high degree of gene expression and regulatory network variation across even a shallow level of evolutionary divergence. We use these data to test hypotheses about the roles of specific trans-factors and cis-regulatory elements, how these roles may vary across venom genes and gene families, and how variation in regulatory systems drive diversity in venom phenotypes. Our results illustrate that differences in chromatin and genotype at regulatory elements play major roles in modulating expression. However, we also find that enhancer deletions, differences in transcription factor expression, and variation in activity of the insulator protein CTCF also likely impact venom phenotypes. Our findings provide insight into the diversity and gene-specificity of gene regulatory features and highlight the value of comparative studies to link gene regulatory network variation to phenotypic variation. [ABSTRACT FROM AUTHOR]

Envenoming resulting from snakebites is recognized as a priority neglected tropical disease by The World Health Organization. The Bothrops genus, consisting of different pitviper species, is considered the most medically significant taxa in Central and South America. Further research into Bothrops venom composition is important to aid in the development of safer and more effective snakebite treatments. In addition, the discovery of Bothrops toxins that could potentially be used for medical or diagnostic purposes is of interest to the pharmaceutical industry. This study aimed to employ high-throughput (HT) venomics to qualitatively analyze venom composition while utilizing coagulation bioassays for identifying coagulopathic toxins and characterizing coagulopathic activity in various Bothrops venoms. Using the recently demonstrated HT venomics workflow in combination with post-column coagulopathic bioassaying, focus was placed at anticoagulant toxins. Well-known procoagulant toxins were also investigated, taking into account that using the HT venomics workflow, procoagulant toxins are especially prone to denaturation during the reversed-phase chromatographic separations performed in the workflow. The findings revealed that the venoms of B. atrox and B. jararaca harbored procoagulant toxins, whereas those of B. alternatus and B. neuwiedi contained both procoagulant and anticoagulant toxins. In general, anticoagulation was associated with phospholipases A2s, while procoagulation was associated with snake venom metalloproteinases and snake venom serine proteases. These results showed the identification of coagulopathic venom toxins in the Bothrops venoms analyzed using multiple analytical methods that complement each other. Additionally, each venom underwent qualitative characterization of its composition. [ABSTRACT FROM AUTHOR]

This study investigated the intraspecific and interspecific variability in the venom effects of Agkistrodon viperid snake species and subspecies (eleven venoms total) on plasma clotting times, fibrinogen levels, and fibrin clot strength. Significant delays in plasma clotting time were observed for A. conanti, A. contortrix mokasen, A. contortrix phaeogaster, A. howardgloydi, A. piscivorus leucostoma, and A. piscivorus piscivorus. Notably, the phylogenetically disjunct lineages A. conanti, A. contortrix mokasen, and A. howardgloydi exhibited the most potent anticoagulant effects, indicating the independent amplification of a basal trait. Inhibition assays with the activated clotting enzymes Factors XIa, IXa, Xa, and IIa (thrombin) revealed that FXa inhibition is another basal trait amplified independently on multiple occasions within the genus, but with A. howardgloydi, notably more potent than all others. Phospholipid degradation and zymogen destruction were identified as mechanisms underlying the variability in venom effects observed experimentally and in previous clinical reports. Thromboelastography demonstrated that the venoms did not clot fibrinogen directly but affected fibrin clot strength by damaging fibrinogen and that thrombin was subsequently only able to cleave into weak, unstable clots. The ability to activate Protein C, an endogenous anticoagulant enzyme, varied across species, with some venoms exceeding that of A. contortrix contortrix, which previously yielded the protein diagnostic agent Protac®. Phylogenetic analysis suggested that both fibrinogen degradation and Protein C activation were each amplified multiple times within the genus, albeit with negative correlation between these two modes of action. This study highlights the evolutionary, clinical, and biodiscovery implications of venom variability in the Agkistrodon species, underscoring their dynamic evolution, emphasising the need for tailored clinical approaches, and highlighting the potential for novel diagnostic and therapeutic developments inspired by the unique properties of snake venoms. [ABSTRACT FROM AUTHOR]

In this paper, we provide an overview of mitochondrial bioenergetics and specific conditions that lead to the formation of non-bilayer structures in mitochondria. Secondly, we provide a brief overview on the structure/function of cytotoxins and how snake venom cytotoxins have contributed to increasing our understanding of ATP synthesis via oxidative phosphorylation in mitochondria, to reconcile some controversial aspects of the chemiosmotic theory. Specifically, we provide an emphasis on the biochemical contribution of delocalized and localized proton movement, involving direct transport of protons though the Fo unit of ATP synthase or via the hydrophobic environment at the center of the inner mitochondrial membrane (proton circuit) on oxidative phosphorylation, and how this influences the rate of ATP synthesis. Importantly, we provide new insights on the molecular mechanisms through which cobra venom cytotoxins affect mitochondrial ATP synthesis, mitochondrial structure, and dynamics. Finally, we provide a perspective for the use of cytotoxins as novel pharmacological tools to study membrane bioenergetics and mitochondrial biology, how they can be used in translational research, and their potential therapeutic applications. [ABSTRACT FROM AUTHOR]

The stimulator of interferon genes (STING) connects the innate and adaptive immune system and plays a significant role in antitumor immunity. Over the past decades, endogenous and CDN-derived STING agonists have been a hot topic in the research of cancer immunotherapies. However, these STING agonists are either in infancy with limited biological effects or have failed in clinical trials. In 2020, a non-nucleotide STING agonist MSA-2 was identified, which exhibited satisfactory antitumor effects in animal studies and is amenable to oral administration. Due to its distinctive binding mode and enhanced bioavailability, there have been accumulating interests and an array of studies on MSA-2 and its derivatives, spanning its structure-activity relationship, delivery systems, applications in combination therapies, etc. Here, we provide a comprehensive review of MSA-2 and interventional strategies based on this family of STING agonists to help more researchers extend the investigation on MSA-2 in the future. [Display omitted] [ABSTRACT FROM AUTHOR]