First catalog of spiders of Egypt (Araneae)

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  First catalog of spiders of Egypt (Araneae) Abstract This study provides a comprehensive catalog of the spider fauna of Egypt, comprising 389 species assigned to 197 genera and 40 families. For each species, all published locality records are compiled and accompanied by complete bibliographic references. The dataset has been carefully reviewed and critically evaluated in light of the most recent taxonomic and faunistic information. Among the recorded species, 55 (14.13%) are currently known only from Egypt and are thus considered endemic. Based on the World Spider Catalog (2026), 28 species are treated as nomina dubia, 23 species lack confirmed records from Egypt, which is not correct, 10 have to be omitted from the Egyptian list and 8 are species inquirenda. Despite the relatively high number of documented species, the Egyptian araneofauna remains insufficiently explored. Given the country’s ecological diversity and biogeographical position, further research is expected to signi...

In vitro inhibition of snake venom toxins by varespladib, marimastat, nafamostat and dimercaprol

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By Holger Krisp - Own work, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=17574465

In vitro inhibition of snake venom toxins by varespladib, marimastat, nafamostat and dimercaprol

Abstract

Snakebite envenoming causes more than 130,000 deaths and more than 400,000 disabilities per year and has been classified as a priority Neglected Tropical Disease by the World Health Organization (WHO). While antivenom therapy remains the mainstay of snakebite treatment, small molecule therapeutics (SMTs) have been proposed as potential adjuncts to antivenom, particularly as oral treatment in the prehospital setting. Several SMTs have demonstrated efficacy in preclinical models of snakebite envenoming, with varespladib, a secreted phospholipase A2 (sPLA2) inhibitor, being granted orphan drug status for its potential to treat snakebite. The present study investigated the potential of four SMTs (e.g., varespladib, marimastat, nafamostat and dimercaprol) to neutralise toxic components present in the venom of southern African snake species. In vitro experimentation found that varespladib potently inhibited snake venom phospholipase A2 (svPLA2) activity in Bitis arietans (IC50 = 0.221 μM) and B. gabonica (IC50 = 0.276 μM). Marimastat exhibited potent inhibition of snake venom metalloproteinase (svMP) in several snake species with IC50 values ranging from 0.0042–3.06 μM, while dimercaprol, a metal chelator, was a lower potency svMP inhibitor with IC50 values ranging from 5.01–79.8 μM. Nafamostat proved to be an inhibitor of snake venom serine protease (svSP) in B. arietans (IC50 = 3.72 μM), B. gabonica (IC50 = 3.80 μM) and Causus rhombeatus (IC50 = 0.261 μM). These data demonstrate that SMTs are effective inhibitors of the relevant enzymes in several snake species and support the proposal that SMTs could be developed for therapeutic intervention in snakebite envenoming.
Le Roux, A., Cloete, S. J., Petzer, J. P., & Petzer, A. (2025). In vitro inhibition of snake venom toxins by varespladib, marimastat, nafamostat and dimercaprol. Toxicon, 108626. https://doi.org/10.1016/j.toxicon.2025.108626