Cytotoxicity of Cerastes cerastes snake venom: Involvement of imbalanced redox status

Effect of Egyptian Spitting Cobra Naja nubiae Crude Venom on Immunogenic Activity of Rats

Snakes show defensive activities, often counting visual or auditory displays against an aggressor. The study observed what happens to rats administered subcutaneously sub-lethal doses of crude venom Naja nubiae. The pro-inflammatory cytokines, such as tumor necrosis alpha (TNF-α) and interleukin-6 (IL-6), as well as the anti-inflammatory cytokines such as interleukin-10 (IL-10), and inflammatory mediator's prostaglandin E-2 (PG-E2), were evaluated. Vascular permeability (VP) was employed to assess how leaky or permeable blood vessels are in various tissues and organs, including the rat peritoneal cavity and lymphoid organs. Lymphoid organs' histological alterations brought on by Nubiae venom. The study found that the two venom doses-1/4 and 1/2 LD50-induced high levels of inflammatory activity as evidenced by the production of inflammatory cytokines. These findings demonstrated that venom enhanced innate immunity through specifically increased T helper cells, IL-6, TNF-α, IL-10, and PG-E2. The results reveal whether the venom has an immunomodulatory effect and promotes inflammation. The data have a substantial impact on the development of new drugs and treatments for inflammatory conditions.

Therapeutic outcome of quercetin nanoparticles on Cerastes cerastes venom-induced hepatorenal toxicity: a preclinical study

Aim: The objective of this study was to investigate the therapeutic potential of quercetin (QT) and QT-loaded poly(lactic-co-glycolic acid) nanoparticles (QT-NPs) on Cerastes cerastes venom-mediated inflammation, redox imbalance, hepatorenal tissue damage and local hemorrhage. Methods: The developed QT-NPs were first submitted to physicochemical characterization and then evaluated in the 'challenge then treat' and 'preincubation' models of envenoming. Results: QT-NPs efficiently alleviated hepatorenal toxicity, inflammation and redox imbalance and significantly attenuated venom-induced local hemorrhage. Interestingly, QT-NPs were significantly more efficient than free QT at 24 h post-envenoming, pointing to the efficacy of this drug-delivery system. Conclusion: These findings highlight the therapeutic potential of QT-NPs on venom-induced toxicity and open up the avenue for their use in the management of snakebite envenoming.

Prospecting for candidate molecules from Conus virgo toxins to develop new biopharmaceuticals

Background

A combination of pharmacological and biomedical assays was applied in this study to examine the bioactivity of Conus virgo crude venom in order to determine the potential pharmacological benefit of this venom, and its in vivo mechanism of action.

Methods

Two doses (1/5 and 1/10 of LC₅₀, 9.14 and 4.57 mg/kg) of the venom were used in pharmacological assays (central and peripheral analgesic, anti-inflammatory and antipyretic), while 1/2 of LC₅₀ (22.85 mg/kg) was used in cytotoxic assays on experimental animals at different time intervals, and then compared with control and reference drug groups.

Results

The tail immersion time was significantly increased in venom-treated mice compared with the control group. Also, a significant reduction in writhing movement was recorded after injection of both venom doses compared with the control group. In addition, only the high venom concentration has a mild anti-inflammatory effect at the late inflammation stage. The induced pyrexia was also decreased significantly after treatment with both venom doses. On the other hand, significant increases were observed in lipid peroxidation (after 4 hours) and reduced glutathione contents and glutathione peroxidase activity, while contents of lipid peroxidation and nitric oxide (after 24 hours) and catalase activity were depleted significantly after venom administration.

Conclusion

These results indicated that the crude venom of Conus virgo probably contain bioactive components that have pharmacological activities with low cytotoxic effects. Therefore, it may comprise a potential lead compound for the development of drugs that would control pain and pyrexia.

Mechanistic Insights into the Leishmanicidal and Bactericidal Activities of Batroxicidin, a Cathelicidin-Related Peptide from a South American Viper (Bothrops atrox)

Snake venoms are important sources of bioactive molecules, including those with antiparasitic activity. Cathelicidins form a class of such molecules, which are produced by a variety of organisms. Batroxicidin (BatxC) is a cathelicidin found in the venom of the common lancehead (Bothrops atrox). In the present work, BatxC and two synthetic analogues, BatxC(C-2.15Phe) and BatxC(C-2.14Phe)des-Phe1, were assessed for their microbicidal activity. All three peptides showed a broad-spectrum activity on Gram-positive and -negative bacteria, as well as promastigote and amastigote forms of Leishmania (Leishmania) amazonensis. Circular dichroism (CD) and nuclear magnetic resonance (NMR) data indicated that the three peptides changed their structure upon interaction with membranes. Biomimetic membrane model studies demonstrated that the peptides exert a permeabilization effect in prokaryotic membranes, leading to cell morphology distortion, which was confirmed by atomic force microscopy (AFM). The molecules considered in this work exhibited bactericidal and leishmanicidal activity at low concentrations, with the AFM data suggesting membrane pore formation as their mechanism of action. These peptides stand as valuable prototype drugs to be further investigated and eventually used to treat bacterial and protozoal infections.

Development and evaluation of polymeric nanoparticles as a delivery system for snake envenoming prevention

Polymer-based nanoparticles have become an appealing carrier for improving vaccine delivery efficiency. In this study, we investigated an interesting approach based on PLGA nanoparticles encapsulating Cerastes cerastes venom as an intranasal vaccine delivery system for snake envenomation prevention. Particles were synthesized by double emulsion solvent evaporation method and characterized for their size, morphology, distribution, and venom-nanoparticles interactions. An immunization trial was performed in mice by the intranasal route to evaluate the immune response, the reactogenicity, and the protective effect of this nanovaccine. The physicochemical and structural characteristics of Cc-loaded PLGA NPs revealed that the particles exhibited a spherical shape with a diameter of 370 nm, and a negatively charged surface with a zeta potential value of 19,9 mV. The immunization with Cc-PLGA NPs can induce a systemic innate and humoral immune response and confers protection against Cerastes cerastes venom (Cc) over than 6 LD50 with a cross-protection against Vipera lebetina venom (Vl) over than 5 LD50. Nano-encapsulation of Cc venom reduced its toxicity and the induced tissue alterations. Our results confirm that the nano-formulation Cc-PLGA NPs is a potent adjuvant system that improve the humoral immune response and provide protection against high lethal doses of viper venoms.