Samsum ant venom modulates the immune response and redox status at the acute toxic dose in vivo

Alternative biological models for evaluation of the toxic, genotoxic and mutagenic potential of Ectatomma brunneum Smith venom

The venom of Ectatomma brunneum is considered promising for drugs development. Therefore, it is important to evaluate its toxic potential and genetic instability using biological assays. To this end, toxicity assays were performed with Artemia salina, cytotoxicity and genotoxicity with Allium cepa and mutagenicity with Ames. The results indicated toxicity to A. salina, and no cytotoxic, genotoxic or mutagenic potential at concentrations equal to or lower than 500 μg/mL for the other tests.

Recombinant antigen 5 from Polybia paulista wasp venom (Hymenoptera, Vespidae): Antigen-specific antibody production and functional profile of CD4+ T cells in the immune response

Polybia paulista is a neotropical social wasp related to severe accidents and allergic reactions cases, including anaphylaxis, in southeastern Brazil. Antigen 5 (Poly p 5) is a major allergenic protein from its venom with potential use for component-resolved diagnostic. Therefore, the previous characterization of the immune response profile triggered by Poly p 5 should be evaluated. Recombinant Poly p 5 (rPoly p 5) was used to sensitize BALB/c mice with six weekly intradermal doses, and the specific antibody production and the functional profile of CD4+ T cells were assessed. rPoly p 5 induced the production of specific immunoglobulins (sIg) sIgE, sIgG1 and sIgG2a, which could recognize natural Poly p 5 presented in the venom of four different wasp species. rPoly p 5 stimulated in vitro the CD4+ T cells from immunized mice, which showed a significant proliferative response. These antigen-specific CD4+T cells produced IFN-γ and IL-17A cytokines and increased ROR-γT transcription factor expression. No differences between the control group and sensitized mice were found in IL-4 production and GATA-3 and T-bet expression. Interestingly, increased CD25+FoxP3+ regulatory T cells (Tregs) frequency was observed in the splenocyte cell cultures from rPoly p 5 immunized mice after the in vitro stimulation with both P. paulista venom extract and rPoly p 5. Here we showed that rPoly p 5 induces antigen-specific antibodies capable of recognizing Antigen 5 in the venom of four wasp species and modulates antigen-specific CD4+ T cells to IFN-γ production response associated with a Th17 profile in sensitized mice. These findings emphasize the potential use of rPoly p 5 as an essential source of a major wasp allergen with significant immunological properties.

Shedding Lights on Crude Venom from Solitary Foraging Predatory Ant Ectatomma opaciventre: Initial Toxinological Investigation

Some species of primitive predatory ants, despite living in a colony, exercise their hunting collection strategy individually; their venom is painful, paralyzing, digestive, and lethal for their prey, yet the toxins responsible for these effects are poorly known. Ectatomma opaciventre is a previously unrecorded solitary hunting ant from the Brazilian Cerrado. To overcome this hindrance, the present study performed the in vitro enzymatic, biochemical, and biological activities of E. opaciventre to better understand the properties of this venom. Its venom showed several proteins with masses ranging from 1-116 kDa, highlighting the complexity of this venom. Compounds with high enzymatic activity were described, elucidating different enzyme classes present in the venom, with the presence of the first L-amino acid oxidase in Hymenoptera venoms being reported. Its crude venom contributes to a state of blood incoagulability, acting on primary hemostasis, inhibiting collagen-induced platelet aggregation, and operating on the fibrinolysis of loose red clots. Furthermore, the E. opaciventre venom preferentially induced cytotoxic effects on lung cancer cell lines and three different species of Leishmania. These data shed a comprehensive portrait of enzymatic components, biochemical and biological effects in vitro, opening perspectives for bio-pharmacological application of E. opaciventre venom molecules.

Anti-inflammatory activities of arthropod peptides: a systematic review

Peptides obtained from different animal species have gained importance recently due to research that aims to develop biopharmaceuticals with therapeutic potential. In this sense, arthropod venoms have drawn attention, not only because of their toxicity but mainly for the search for molecules with various bioactivities, including anti-inflammatory activity. The purpose of the present study is to gather data available in the literature on new peptides derived from arthropod species with anti-inflammatory potential. This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Studies on peptides from arthropods that display anti-inflammatory activity were retrieved from PubMed, Scopus, Web of Science, and Google Scholar databases. The bibliographic research started in 2020 and searched papers without a limit on the publication date. The articles were analyzed using a search string containing the following terms: "Peptides" and "Anti-inflammatory", in combinations such as "Ant", "Bee", "Wasp", "Crab", "Shrimp", "Scorpion", "Spider", "Tick" and "Centipedes". Besides, a search was carried out in the databases with the terms: "Peptides", "Antitumor", or "Anticancer", and "Arthropods". Articles that met the inclusion and exclusion criteria totalized 171, and these served for data extraction. Additionally, the present review included anti-inflammatory peptides with anticancer properties. Peptides with confirmed anti-inflammatory activity were from insects (ants, bees, and wasps), crustaceans (shrimp and crabs), arachnids (scorpions, spiders, and ticks), and centipedes. These arthropod peptides act mainly by decreasing pro-inflammatory cytokines as analyzed in vitro and in vivo. Some showed significant antineoplastic activity, working in essential cellular pathways against malignant neoplasms.

Samsum ant venom protects against carbon tetrachloride-induced acute spleen toxicity in vivo

Many active molecules used in the development of new drugs are produced by ants. Present study assessed antioxidant and anti-inflammatory properties of Samsum ant venom (SAV) extract in carbon tetrachloride (CCL₄)-induced spleen toxicity. Toxicity and oxidative stress were measured in four experimental groups: a negative control group without any treatment, a positive control group (CCl₄-treated rats; a single dose of 1 ml/kg CCL₄), an experimental group of CCl₄-treated rats co-treated daily with SAV (100 μl), and a group to determine safe use with rats treated only with SAV (100 μl) daily for 3 weeks. CCl₄-treatment led to an elevation in toxicity and oxidative stress. CCl₄ significantly elevated malondialdehyde (MDA) levels, as well as expression of inhibitor of κB (IκB) and tumor necrosis factor-α (TNF-α) proteins. On the other hand, a decrease in glutathione (GSH) and catalase (CAT) levels were detected in CCl₄-treated rats. Co-treatment with SAV was found to reduce these inflammatory and oxidative parameters. SAV elucidated a significant recovery of MDA concentration as well as a significant restoration in GSH levels compared to CCl₄-treated rats; however, SAV increased CAT levels compared to normal rats. Hence, SAV was found to restore splenomegaly induced in CCl₄-treated rats. Histopathological analysis also favored the biochemical analysis showing improvement in splenic architecture in CCl₄ and SAV co-treated rats. The antioxidant properties of SAV may potentially enhance anti-inflammatory actions and improve spleen structure and function in CCl₄-challenged rats.