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Toxins Jan 2020Arthropods comprise a predominant and well-succeeded phylum of the animal kingdom that evolved and diversified in millions of species grouped in four subphyla, namely,...
Arthropods comprise a predominant and well-succeeded phylum of the animal kingdom that evolved and diversified in millions of species grouped in four subphyla, namely, Chelicerata (arachnids), Crustacea, Myriapoda (centipedes), and Hexapoda (insects) [...].
Topics: Animals; Arthropod Venoms; Insecticides; Peptides
PubMed: 31991714
DOI: 10.3390/toxins12020082 -
Toxicon : Official Journal of the... Sep 2018Arthropods are a diverse and ancient group of invertebrate animals, which constitute approximately 75-85% of all known species on earth. Many arthropod species, such as... (Review)
Review
Arthropods are a diverse and ancient group of invertebrate animals, which constitute approximately 75-85% of all known species on earth. Many arthropod species, such as spiders, scorpions and even some crustaceans, contain venoms that can be very complex, representing natural combinatorial libraries of bioactive compounds. Characterization of the compounds in these libraries has helped the development of tools for pharmacology, and the discovery of lead molecules for therapeutic treatments. A critical aspect in the characterization of venom compounds is determination of three-dimensional structure. Structural analysis can provide insight into many processes including understanding target interactions and developing more potent and selective drug leads. Arthropod venoms are an extremely rich source of novel structures and this review provides an overview of this structural diversity, including structures of proteins, peptides and small molecules.
Topics: Amino Acid Motifs; Animals; Arthropod Venoms; Arthropods; Peptides; Proteins; Structure-Activity Relationship
PubMed: 30040988
DOI: 10.1016/j.toxicon.2018.07.018 -
Clinical Toxicology (Philadelphia, Pa.) Aug 2019Snakes, insects, arachnids and myriapods have been linked to necrosis following envenomation. However, the pathways involved in arthropod venom-induced necrosis remain... (Review)
Review
Snakes, insects, arachnids and myriapods have been linked to necrosis following envenomation. However, the pathways involved in arthropod venom-induced necrosis remain a highly controversial topic among toxinologists, clinicians and the public. On the one hand, clinicians report on alleged envenomations based on symptoms and the victims' information. On the other hand, toxinologists and zoologists argue that symptoms are incompatible with the known venom activity of target species. This review draws from the literature on arthropod envenomations, snakebite, and inflammatory processes to suggest that envenomation by a range of organisms might trigger an intense inflammatory cascade that ultimately lead to necrosis. If confirmed, these processes would have important implications for the treatment of venom-induced necrosis. To describe two inflammatory pathways of regulated necrosis, tumour necrosis factor (necroptosis) and Neutrophil Extracellular Traps (NETosis); to discuss existing knowledge about snake venom and arachnid-induced necrosis demonstrating the involvement of tumour necrosis factor and neutrophils in the development of tissue necrosis following envenomation and to contribute to the understanding of venom-induced necrosis by arthropods and provide clinicians with an insight into little known inflammatory processes which may occur post envenomation. ISI Web of Science databases were searched using the terms "spider bite necrosis", "arthropod envenomation necrosis", "venom necrosis", "venom immune response", "loxoscelism", "arachnidism", "necroptosis venom", "necroptosis dermatitis", "tumour necrosis factor TNF venom", "scorpionism", "scolopendrism", "centipede necrosis", "NETosis venom", "NETosis necrosis". Searches produced 1737 non-duplicate citations of which 74 were considered relevant to this manuscript. Non-peer-reviewed sources or absence of voucher material identifying the organism were excluded. Necrosis is the breakdown of cell membrane integrity followed by inflowing extracellular fluid, organelle swelling and the release of proteolytic enzymes into the cytosol. Necrosis was historically considered an unregulated process; however, recent studies demonstrate that necrosis can also be a programmed event resulting from a controlled immune response (necroptosis). : Tumour necrosis factor is a pro-inflammatory cytokine involved in regulating immune response, inflammation and cell death/survival. The pro-inflammatory cytokine TNF-α participates in the development of necrosis after envenomation by vipers. Treatment with TNF-α-antibodies may significantly reduce the manifestation of necrosis. The process by which neutrophils discharge a mesh of DNA strands in the extracellular matrix to entangle ("trap") pathogens, preventing them from disseminating. Neutrophil Extracellular Traps have been recently described as important in venom-induced necrosis. Trapped venom accumulates at the bite site, resulting in significant localized necrosis. Insects, myriapods and arachnids can induce necrosis following envenomation. So far, the processes involved have only been investigated in two arachnids: spp. (recluse spiders) and (scorpion). venom contains phospholipases D which hydrolyse sphingomyelin, resulting in lysis of muscle fibers. Subsequently liberated ceramides act as intermediaries that regulate TNF-α and recruit neutrophils. Experiments show that immune-deficient mice injected with venom experience less venom-induced inflammatory response and survive longer than control mice. Necrosis following stings correlates with elevated concentrations of TNF-α. These observations suggest that necrosis may be indirectly triggered or worsened by pathways of regulated necrosis in addition to necrotic venom compounds. Envenomation often induce an intense inflammatory cascade, which under certain circumstances may produce necrotic lesions independently from direct venom activity. This could explain the inconsistent and circumstantial occurrence of necrosis following envenomation by a range of organisms. Future research should focus on identifying pathways to regulated necrosis following envenomation and determining more efficient ways to manage inflammation. We suggest that clinicians should consider the victim's immune response as an integral part of the envenomation syndrome.
Topics: Animals; Arthropod Venoms; Arthropods; Bites and Stings; Databases, Bibliographic; Dermotoxins; Necrosis; Skin Diseases; Tumor Necrosis Factor-alpha
PubMed: 30806093
DOI: 10.1080/15563650.2019.1578367 -
Allergy and Asthma Proceedings Jul 2022Venom immunotherapy (VIT) with Hymenoptera venom extracts is highly effective in preventing large local, systemic allergic, and anaphylactic reactions to insect stings....
Venom immunotherapy (VIT) with Hymenoptera venom extracts is highly effective in preventing large local, systemic allergic, and anaphylactic reactions to insect stings. VIT is not required for patients with cutaneous systemic or large local allergic reactions to stings because it is uncommon for reactions to become more severe. The clinical history, with confirmatory skin or serum tests for venom IgE, can clarify the risk for future anaphylaxis and the need for VIT. For initial treatment, rush regimens are recommended because they have the same or less risk of systemic reactions than slower traditional regimens. VIT is relatively safe with a low incidence of systemic reactions. Injection-site reactions can be bothersome but do not predict systemic reactions to venom injections. Patients who need VIT should be screened for baseline serum tryptase and possible underlying mast cell disorders. VIT can be discontinued after five years in most patients, but those with known high-risk factors should continue VIT indefinitely.
Topics: Allergens; Anaphylaxis; Animals; Arthropod Venoms; Bee Venoms; Desensitization, Immunologic; Humans; Hymenoptera; Immunotherapy; Insect Bites and Stings; Wasp Venoms
PubMed: 35818146
DOI: 10.2500/aap.2022.43.210109 -
The Medical Clinics of North America Jul 2024Stinging insects are a frequent cause of local and systemic hypersensitivity reactions, including anaphylaxis. For those with a history of life-threatening anaphylaxis,... (Review)
Review
Stinging insects are a frequent cause of local and systemic hypersensitivity reactions, including anaphylaxis. For those with a history of life-threatening anaphylaxis, venom immunotherapy is effective, safe, and can be life-saving. Arachnids are a much less common source of envenomation through bites or stings and are less likely to cause a hypersensitivity reaction. However, recognizing the clinical manifestations when they do present is important for accurate diagnosis and treatment, and, when indicated, consideration of other diagnoses.
Topics: Humans; Insect Bites and Stings; Anaphylaxis; Animals; Hypersensitivity; Arthropod Venoms; Desensitization, Immunologic; Venom Hypersensitivity
PubMed: 38816116
DOI: 10.1016/j.mcna.2023.08.008 -
Toxicon : Official Journal of the... Feb 2019The millions of extant arthropod species are testament to their evolutionary success that can at least partially be attributed to venom usage, which evolved...
The millions of extant arthropod species are testament to their evolutionary success that can at least partially be attributed to venom usage, which evolved independently in at least 19 arthropod lineages. While some arthropods primarily use venom for predation (e.g., spiders and centipedes) or defense (e.g., bees and caterpillars), it can also have more specialised functions (e.g. in parasitoid wasps to paralyse arthropods for their brood to feed on) or even a combination of functions (e.g. the scorpion Parabuthus transvaalicus can deliver a prevenom for predator deterrence and a venom for predation). Most arthropod venoms are complex cocktails of water, salts, small bioactive molecules, peptides, enzymes and larger proteins, with peptides usually comprising the majority of toxins. Some spider venoms have been reported to contain >1000 peptide toxins, which function as combinatorial libraries to provide an evolutionary advantage. The astounding diversity of venomous arthropods multiplied by their enormous toxin arsenals results in an almost infinite resource for novel bioactive molecules. The main challenge for exploiting this resource is the small size of most arthropods, which can be a limitation for current venom extraction techniques. Fortunately, recent decades have seen an incredible improvement in transcriptomic and proteomic techniques that have provided increasing sensitivity while reducing sample requirements. In turn, this has provided a much larger variety of arthropod venom compounds for potential applications such as therapeutics, molecular probes for basic research, bioinsecticides or anti-parasitic drugs. This special issue of Toxicon aims to cover the breadth of arthropod venom research, including toxin evolution, pharmacology, toxin discovery and characterisation, toxin structures, clinical aspects, and potential applications.
Topics: Animals; Arthropod Venoms; Arthropods; Biological Evolution; Peptides
PubMed: 30496730
DOI: 10.1016/j.toxicon.2018.11.312 -
Toxicon : Official Journal of the... Feb 2019Comprising of over a million described species of highly diverse invertebrates, Arthropoda is amongst the most successful animal lineages to have colonized aerial,... (Review)
Review
Comprising of over a million described species of highly diverse invertebrates, Arthropoda is amongst the most successful animal lineages to have colonized aerial, terrestrial, and aquatic domains. Venom, one of the many fascinating traits to have evolved in various members of this phylum, has underpinned their adaptation to diverse habitats. Over millions of years of evolution, arthropods have evolved ingenious ways of delivering venom in their targets for self-defence and predation. The morphological diversity of venom delivery apparatus in arthropods is astounding, and includes extensively modified pedipalps, tail (telson), mouth parts (hypostome), fangs, appendages (maxillulae), proboscis, ovipositor (stinger), and hair (urticating bristles). Recent investigations have also unravelled an astonishing venom biocomplexity with molecular scaffolds being recruited from a multitude of protein families. Venoms are a remarkable bioresource for discovering lead compounds in targeted therapeutics. Several components with prospective applications in the development of advanced lifesaving drugs and environment friendly bio-insecticides have been discovered from arthropod venoms. Despite these fascinating features, the composition, bioactivity, and molecular evolution of venom in several arthropod lineages remains largely understudied. This review highlights the prevalence of venom, its mode of toxic action, and the evolutionary dynamics of venom in Arthropoda, the most speciose phylum in the animal kingdom.
Topics: Animals; Arthropod Venoms; Arthropods; Biological Evolution; Ecosystem; Phylogeny
PubMed: 30529476
DOI: 10.1016/j.toxicon.2018.11.433 -
Immunotherapy Feb 2011Subcutaneous venom immunotherapy is the only effective treatment for patients who experience severe hymenoptera sting-induced allergic reactions, and the treatment also... (Review)
Review
Subcutaneous venom immunotherapy is the only effective treatment for patients who experience severe hymenoptera sting-induced allergic reactions, and the treatment also improves health-related quality of life. This article examines advances in various areas of this treatment, which include the immunological mechanisms of early and long-term efficacy, indications and contraindications, selection of venom, treatment protocols, duration, risk factors for systemic reactions in untreated and treated patients as well as for relapse following cessation of treatment. Current and future strategies for improving safety and efficacy are also examined. However, although progress in the past few years has been fruitful, much remains to be accomplished.
Topics: Anaphylaxis; Animals; Arthropod Venoms; Desensitization, Immunologic; Humans; Hymenoptera; Insect Bites and Stings
PubMed: 21322761
DOI: 10.2217/imt.10.88 -
Current Protein & Peptide Science 2020Hymenoptera venom allergy is one of the common causes of anaphylaxis. However, when physicians make the diagnosis of Hymenoptera venom allergy, the history of being... (Review)
Review
Hymenoptera venom allergy is one of the common causes of anaphylaxis. However, when physicians make the diagnosis of Hymenoptera venom allergy, the history of being stung is not always consistent with the results of venom-specific IgE. With the development of component-resolved diagnosis, it is possible to accurately localize an allergic reaction to certain sensitized proteins. This paper reviewed the studies that have addressed the identified allergenicity and cross-reactivity of Hymenoptera venom allergens accepted by the WHO/IUIS Nomenclature Sub-committee, the componentresolved diagnosis of Hymenoptera venom allergy and its predictive values for the efficacy and safety of venom immunotherapy. Also special attention was paid to the spread of Hymenoptera venom allergy in Asian countries.
Topics: Allergens; Anaphylaxis; Animals; Arthropod Venoms; Humans; Hymenoptera; Insecta
PubMed: 31752653
DOI: 10.2174/1389203720666191120130209 -
Toxicon : Official Journal of the... Jun 1995Citrate has been identified as a major component of honey bee (Apis mellifera) venom by gas liquid chromatography-mass spectrometry. A citrate concentration of 9% was... (Comparative Study)
Comparative Study
Citrate has been identified as a major component of honey bee (Apis mellifera) venom by gas liquid chromatography-mass spectrometry. A citrate concentration of 9% was found for dried bee venom by a coupled enzyme assay, aconitase-isocitric dehydrogenase. A liquid honey bee venom would contain 140 mM citrate concentration (if the solids content were 30%). Bee venom phospholipase was inhibited at a 43% level with a citrate concentration of 20 mM and calcium ion at 3 mM with the enzyme assay. Citrate was also found in the venoms of bumble bee, Bombus fervidus, 7%; yellow jacket, Vespula maculifrons, 4%; scorpion, Centruroides sculpturatus, 8%; tarantula, Grammastola cala, 8% and brown recluse spider venom gland extract, Loxoceles reclusa, 1.5% based on dried venom solids. Citrate may serve as an endogenous inhibitor of divalent metal ion-dependent enzymes in arthropod venoms as described by Francis et al. (1992, Toxicon 30, 1239-1246). Many arthropod venoms contain calcium-dependent phospholipases. A direct effect of citrate as a venom component may be possible. The presence of citrate in venoms must be considered in research on receptors, ion channels and divalent ion-dependent toxins.
Topics: Aconitate Hydratase; Animals; Arthropod Venoms; Citrates; Gas Chromatography-Mass Spectrometry; Isocitrate Dehydrogenase; Lizards; Mass Spectrometry; Phospholipases A; Phospholipases A2; Venoms
PubMed: 7676467
DOI: 10.1016/0041-0101(95)00019-i