Exploring the biological activities and proteome of Brazilian scorpion Rhopalurus agamemnon venom

Effects of toxin metalloproteinases from jellyfish Nemopilema nomurai nematocyst on the dermal toxicity and potential treatment of jellyfish dermatitis

Jellyfish dermatitis is a common medical problem in many countries due to the jellyfish envenomation. However, there are no specific and targeted medications for their treatment. Here we investigated the possible therapeutic effects of metalloproteinase inhibitors on the dermal toxicity of Nemopilema nomurai nematocyst venom (NnNV), a giant venomous jellyfish from China, using the jellyfish dermatitis model, focusing on inflammatory effector molecules during jellyfish envenomation. Metalloproteinase may further stimulate inflammation by promoting oxidative stress in the organism and play key roles by activating MAPK and NF-κB, in the pathogenesis of jellyfish dermatitis. And the metalloproteinase inhibitors batimastat and EDTA disodium salt may treat the Jellyfish dermatitis by inhibiting the metalloproteinase activity in NnNV. These observations suggest that the metalloproteinase components of NnNV make a considerable contribution to dermal toxicity as the inflammation effect molecular, and metalloproteinase inhibitors can be regarded as novel therapeutic medicines in jellyfish envenomation. This study contributes to understanding the mechanism of jellyfish dermatitis and suggests new targets and ideas for the treatment of jellyfish envenomation.

Fucoidan may treat jellyfish dermatitis by inhibiting the inflammatory effect of jellyfish venom

Jellyfish dermatitis is a common medical problem caused by jellyfish stings. However, there are no targeted and effective medications for their treatment. Here, the biological activity of fucoidan for treatment of jellyfish dermatitis was investigated for the first time. 3 mg/mL Fucoidan attenuated the inflammatory effects of Nemopilema nomurai nematocyst venom (NnNV), including dermal toxicity and myotoxicity. Fucoidan may decrease the inflammatory effects of NnNV by downregulating MAPK and NF-κB pathways. This may be attributed to the inhibitory effect of fucoidan on metalloproteinases and phospholipase A2 (PLA2) in NnNV. 3 mg/mL fucoidan reduced the metalloproteinase activity in NnNV from 316.33 ± 20.84 U/mg to 177.33 ± 25.36 U/mg, while the inhibition of PLA2 activity in NnNV by 1 mg/mL fucoidan could reach 37.67 ± 3.42 %. Besides, external application of 3 mg/mL fucoidan can effectively alleviate the symptoms of jellyfish dermatitis. These observations suggest that fucoidan has considerable potential for treatment of jellyfish dermatitis and could be regarded as a novel medicine for jellyfish envenomation. This study provides new ideas for treatment of jellyfish envenomation and suggests evidence for the use of fucoidan in the treatment of jellyfish dermatitis as well as broadens the potential application of fucoidan in clinical practice.

Scorpion Venom as a Source of Antimicrobial Peptides: Overview of Biomolecule Separation, Analysis and Characterization Methods

Scorpion venoms have long captivated scientific researchers, primarily due to the potency and specificity of the mechanism of action of their derived components. Among other molecules, these venoms contain highly active compounds, including antimicrobial peptides (AMPs) and ion channel-specific components that selectively target biological receptors with remarkable affinity. Some of these receptors have emerged as prime therapeutic targets for addressing various human pathologies, including cancer and infectious diseases, and have served as models for designing novel drugs. Consequently, extensive biochemical and proteomic investigations have focused on characterizing scorpion venoms. This review provides a comprehensive overview of the key methodologies used in the extraction, purification, analysis, and characterization of AMPs and other bioactive molecules present in scorpion venoms. Noteworthy techniques such as gel electrophoresis, reverse-phase high-performance liquid chromatography, size exclusion chromatography, and "omics" approaches are explored, along with various combinations of methods that enable bioassay-guided venom fractionation. Furthermore, this review presents four adapted proteomic workflows that lead to the comprehensive dissection of the scorpion venom proteome, with an emphasis on AMPs. These workflows differ based on whether the venom is pre-fractionated using separation techniques or is proteolytically digested directly before further proteomic analyses. Since the composition and functionality of scorpion venoms are species-specific, the selection and sequence of the techniques for venom analyses, including these workflows, should be tailored to the specific parameters of the study.

Comparative Proteomic Analysis of the Venoms from the Most Dangerous Scorpions in Morocco: Androctonus mauritanicus and Buthus occitanus

Morocco is known to harbor two of the world's most dangerous scorpion species: the black Androctonus mauritanicus (Am) and the yellow Buthus occitanus (Bo), responsible for 83% and 14% of severe envenomation cases, respectively. Scorpion venom is a mixture of biological molecules of variable structures and activities, most of which are proteins of low molecular weights referred to as toxins. In addition to toxins, scorpion venoms also contain biogenic amines, polyamines, and enzymes. With the aim of investigating the composition of the Am and Bo venoms, we conducted an analysis of the venoms by mass spectrometry (ESI-MS) after separation by reversed-phase HPLC chromatography. Results from a total of 19 fractions obtained for the Am venom versus 22 fractions for the Bo venom allowed the identification of approximately 410 and 252 molecular masses, respectively. In both venoms, the most abundant toxins were found to range between 2-5 kDa and 6-8 kDa. This proteomic analysis not only allowed the drawing of an extensive mass fingerprint of the Androctonus mauritanicus and Buthus occitanus venoms but also provided a better insight into the nature of their toxins.

Toxin diversity revealed by de novo transcriptome assembly for venom gland in two species of spiders (Trichonephila clavata and Sinopoda pengi)

During long-term predator-prey coevolution, spiders have generated a vast diversity of toxins. Trichonephila clavata is a web-spinning spider whose large, well-constructed webs and venomous arsenal facilitate prey capture. In contrast, Sinopoda pengi is an ambush predator with agile locomotion and strong chelicerae for hunting. In this study, transcriptomic analysis was performed to describe the predicted toxins of S. pengi and T. clavata. A total of 43 and 47 of these unigenes from S. pengi and T. clavata, respectively, were predicted to have toxin activity. Putative neurotoxins were classified to the family level according to cysteine arrangement; 4 and 6 toxin families were produced by S. pengi and T. clavata, respectively. In addition, potential metalloproteases, acetylcholinesterases, serine proteases, hyaluronidases and phospholipases were found by annotation in databases. In summary, molecular templates with potential application value for medical and biological fields were obtained by classifying and characterizing presumed venom components, which established a foundation for further study of venom.

The Enzymatic Core of Scorpion Venoms

Enzymes are an integral part of animal venoms. Unlike snakes, in which enzymes play a primary role in envenomation, in scorpions, their function appears to be ancillary in most species. Due to this, studies on the diversity of scorpion venom components have focused primarily on the peptides responsible for envenomation (toxins) and a few others (e.g., antimicrobials), while enzymes have been overlooked. In this work, a comprehensive study on enzyme diversity in scorpion venoms was performed by transcriptomic and proteomic techniques. Enzymes of 63 different EC types were found, belonging to 330 orthogroups. Of them, 24 ECs conform the scorpion venom enzymatic core, since they were determined to be present in all the studied scorpion species. Transferases and lyases are reported for the first time. Novel enzymes, which can play different roles in the venom, including direct toxicity, as venom spreading factors, activators of venom components, venom preservatives, or in prey pre-digestion, were described and annotated. The expression profile for transcripts coding for venom enzymes was analyzed, and shown to be similar among the studied species, while being significantly different from their expression pattern outside the telson.