Harvestmen (Arachnida: Opiliones) as Overlooked Predators of Anurans in the Neotropics

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  Harvestmen (Arachnida: Opiliones) as Overlooked Predators of Anurans in the Neotropics ABSTRACT Arthropods are traditionally viewed as invertebrate prey and as predators of other invertebrates, whereas vertebrates are typically considered their predators. However, this paradigm has increasingly been challenged, particularly among arachnids. While several invertebrates are well documented as frog predators, the capacity of particular groups, such as harvestmen (Opiliones), to prey on vertebrates has remained largely anecdotal. Here we report novel field observations of anuran predation by multiple Cranaidae harvestman species across several Neotropical localities. These records include the active capture and consumption of live frogs, demonstrating their role as opportunistic mesopredators. Our findings expand current knowledge of Opiliones ecology by confirming that vertebrate predation occurs across multiple species and localities. Our results suggest that vertebrate consumption...

Botulinum neurotoxin A alleviates Deinagkistrodon acutus venom-induced limb injury through promoting macrophage polarization in rabbits

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By No machine-readable author provided. Danleo~commonswiki assumed (based on copyright claims). - No machine-readable source provided. Own work assumed (based on copyright claims)., CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=648948

Botulinum neurotoxin A alleviates Deinagkistrodon acutus venom-induced limb injury through promoting macrophage polarization in rabbits

Abstract

Objective

Envenomation by Deinagkistrodon acutus (D. acutus) often results in severe limb damage, but therapeutic strategies to counteract the damage are limited. Botulinum neurotoxin A (BoNT/A) has shown protective effects in various models of tissue damage. The present study employed a rabbit model of D. acutus-induced limb damage to investigate the potential therapeutic use and underlying mechanisms of BoNT/A.

Methods

Twenty-two New Zealand white rabbits were randomly assigned to three groups: Sham (S, n = 6), Snake Venom (SV, n = 8), and Snake Venom plus BoNT/A (SV + BoNT/A, n = 8). D. acutus venom was injected intramuscularly into the left thigh to cause limb injury. Antivenom (80 U/kg) was given intravenously 2 h later. In the SV + BoNT/A group, BoNT/A was injected subcutaneously around the venom injection site immediately after modeling. The myoglobin, serum creatine kinase, and limb circumference were monitored. After 24 h, muscle tissue near the injection site was collected for histological evaluation, assessment of apoptosis (cleaved caspase-3), analysis of TNF-α, IL-6, and IL-10, and examination of macrophage polarization markers.

Results

Both SV and SV + BoNT/A groups displayed significant increases in limb swelling, inflammatory cytokines, apoptosis, histological damage, macrophage polarization in comparison to the Sham group. Treatment with BoNT/A reduced pro-inflammatory cytokines (TNF-α, IL-6) while increasing IL-10 (P < 0.05). Moreover, BoNT/A decreased the proportion of CD86+ and iNOS + cells (M1 phenotype) while increasing the proportion of CD206+ and Arg1+ cells (M2 phenotype).

Conclusion

BoNT/A alleviates D. acutus -induced limb injury in rabbits potentially through promoting macrophage polarization.
Xie, L., Wu, H., Lai, L., Du, W., Xu, J., & Lan, P. (2026). Botulinum neurotoxin A alleviates Deinagkistrodon acutus venom-induced limb injury through promoting macrophage polarization in rabbits. Toxicon, 270, 108936. https://doi.org/10.1016/j.toxicon.2025.108936