Journal of Venomous Animals and Toxins Including Tropical Diseases最新文献

{"title":"Fraction of <i>C. d. collilineatus</i> venom containing crotapotin protects PC12 cells against MPP ⁺ toxicity by activating the NGF-signaling pathway.","authors":"Carolina Petri Bernardes, Ernesto Lopes Pinheiro, Isabela Gobbo Ferreira, Isadora Sousa de Oliveira, Neife Aparecida Guinaim Dos Santos, Suely Vilela Sampaio, Eliane Candiani Arantes, Antonio Cardozo Dos Santos","doi":"10.1590/1678-9199-JVATITD-2023-0056","DOIUrl":"10.1590/1678-9199-JVATITD-2023-0056","url":null,"abstract":"<p><strong>Background: </strong>Parkinson's disease (PD) is the second most prevalent neurodegenerative disease. There is no effective treatment for neurodegenerative diseases. Snake venoms are a cocktail of proteins and peptides with great therapeutic potential and might be useful in the treatment of neurodegenerative diseases. Crotapotin is the acid chain of crotoxin, the major component of <i>Crotalus durissus collilineatus</i> venom. PD is characterized by low levels of neurotrophins, and synaptic and axonal degeneration; therefore, neurotrophic compounds might delay the progression of PD. The neurotrophic potential of crotapotin has not been studied yet.</p><p><strong>Methods: </strong>We evaluated the neurotrophic potential of crotapotin in untreated PC12 cells, by assessing the induction of neurite outgrowth. The activation of the NGF signaling pathway was investigated through pharmacological inhibition of its main modulators. Additionally, its neuroprotective and neurorestorative effects were evaluated by assessing neurite outgrowth and cell viability in PC12 cells treated with the dopaminergic neurotoxin MPP⁺ (1-methyl-4-phenylpyridinium), known to induce Parkinsonism in humans and animal models.</p><p><strong>Results: </strong>Crotapotin induced neuritogenesis in PC12 cells through the NGF-signaling pathway, more specifically, by activating the NGF-selective receptor trkA, and the PI3K/Akt and the MAPK/ERK cascades, which are involved in neuronal survival and differentiation. In addition, crotapotin had no cytotoxic effect and protected PC12 cells against the inhibitory effects of MPP⁺ on cell viability and differentiation.</p><p><strong>Conclusion: </strong>These findings show, for the first time, that crotapotin has neurotrophic/neuroprotective/neurorestorative potential and might be beneficial in Parkinson's disease. Additional studies are necessary to evaluate the toxicity of crotapotin in other cell models.</p>","PeriodicalId":17565,"journal":{"name":"Journal of Venomous Animals and Toxins Including Tropical Diseases","volume":"30 ","pages":"e20230056"},"PeriodicalIF":1.8,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11194915/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141446435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Delayed repair of the facial nerve and its negative impacts on nerve and muscle regeneration.","authors":"Cleuber Rodrigo de Souza Bueno, Daniela Vieira Buchaim, Benedito Barraviera, Rui Seabra Ferreira, Paulo Sérgio da Silva Santos, Carlos Henrique Bertoni Reis, Marcelo Augusto Cini, Milton Carlos Kuga, Geraldo Marco Rosa, Rogerio Leone Buchaim","doi":"10.1590/1678-9199-JVATITD-2023-0093","DOIUrl":"10.1590/1678-9199-JVATITD-2023-0093","url":null,"abstract":"<p><strong>Background: </strong>In this experimental protocol, we evaluated the immediate and delayed repair of the buccal branch of the facial nerve (BBFN) with heterologous fibrin biopolymer (HFB) as a coaptation medium and the use of photobiomodulation (PBM), performing functional and histomorphometric analysis of the BBFN and perioral muscles.</p><p><strong>Methods: </strong>Twenty-eight rats were divided into eight groups using the BBFN bilaterally (the left nerve was used for PBM), namely: G1 - control group, right BBFN (without injury); G2 - control group, left BBFN (without injury + PBM); G3 - Denervated right BBFN (neurotmesis); G4 - Denervated left BBFN (neurotmesis + PBM); G5 - Immediate repair of right BBFN (neurotmesis + HFB); G6 - Immediate repair of left BBFN (neurotmesis + HFB + PBM); G7 - Delayed repair of right BBFN (neurotmesis + HFB); G8 - Delayed repair of left BBFN (neurotmesis + HFB + PBM). Delayed repair occurred after two weeks of denervation. All animals were sacrificed after six weeks postoperatively.</p><p><strong>Results: </strong>In the parameters of the BBFN, we observed inferior results in the groups with delayed repair, in relation to the groups with immediate repair, with a significant difference (<i>p</i> < 0.05) in the diameter of the nerve fiber, the axon, and the thickness of the myelin sheath of the group with immediate repair with PBM compared to the other experimental groups. In measuring the muscle fiber area, groups G7 (826.4 ± 69.90) and G8 (836.7 ± 96.44) were similar to G5 (882.8 ± 70.51). In the functional analysis, the G7 (4.10 ± 0.07) and G8 (4.12 ± 0.08) groups presented normal parameters.</p><p><strong>Conclusion: </strong>We demonstrated that delayed repair of BBFN is possible with HFB, but with worse results compared to immediate repair, and that PBM has a positive influence on nerve regeneration results in immediate repair.</p>","PeriodicalId":17565,"journal":{"name":"Journal of Venomous Animals and Toxins Including Tropical Diseases","volume":"30 ","pages":"e20230093"},"PeriodicalIF":2.4,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11132725/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141161911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of local and systemic treatment with human natural killer-1 mimetic peptide (HNK-1) after ventral root avulsion and reimplantation in mice.","authors":"Natalia Scanavachia da Silva, Julia Lombardi, Frank Kirchhoff, Rui Seabra Ferreira, Benedito Barraviera, Alexandre Leite Rodrigues de Oliveira, Luciana Politti Cartarozzi","doi":"10.1590/1678-9199-JVATITD-2023-0065","DOIUrl":"10.1590/1678-9199-JVATITD-2023-0065","url":null,"abstract":"<p><strong>Background: </strong>Spinal ventral root injuries generate significant motoneuron degeneration, which hinders full functional recovery. The poor prognosis of functional recovery can be attributed to the use or combination of different therapeutic approaches. Several molecules have been screened as potential treatments in combination with surgical reimplantation of the avulsed roots, the gold standard approach for such injuries. Among the studied molecules, human natural killer-1 (HNK-1) stands out as it is related to the stimulation of motor axon outgrowth. Therefore, we aimed to comparatively investigate the effects of local administration of an HNK-1 mimetic peptide (mp-HNK-1) and systemic treatment with ursolic acid (UA), another HNK-1 mimetic, after ventral root avulsion and reimplantation with heterologous fibrin biopolymer (HFB).</p><p><strong>Methods: </strong>Female mice of the isogenic strain C57BL/6JUnib were divided into five experimental groups: Avulsion, Reimplantation, mp-HNK-1 (in situ), and UA (systemic treatment). Mice were evaluated 2 and 12 weeks after surgery. Functional assessment was performed every four days using the Catwalk platform. Neuronal survival was analyzed by cytochemistry, and glial reactions and synaptic coverage were evaluated by immunofluorescence.</p><p><strong>Results: </strong>Treatment with UA elicited long-term neuroprotection, accompanied by a decrease in microglial reactions, and reactive astrogliosis. The neuroprotective effects of UA were preceded by increased glutamatergic and GABAergic inputs in the ventral spinal cord two weeks after injury. However, a single application of mp-HNK-1 had no significant effects. Functional analysis showed that UA treatment led to an improvement in motor and sensory recovery.</p><p><strong>Conclusion: </strong>Overall, the results indicate that UA is neuroprotective, acting on glial cells and synaptic maintenance, and the combination of these findings led to a better functional recovery.</p>","PeriodicalId":17565,"journal":{"name":"Journal of Venomous Animals and Toxins Including Tropical Diseases","volume":"30 ","pages":"e20230065"},"PeriodicalIF":2.4,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11105159/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141070344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acute phase reactions in <i>Daboia siamensis</i> venom and fraction-induced acute kidney injury: the role of oxidative stress and inflammatory pathways in <i>in vivo</i> rabbit and <i>ex vivo</i> rabbit kidney models.","authors":"Narongsak Chaiyabutr, Jureeporn Noiprom, Kanyanat Promruangreang, Taksa Vasaruchapong, Panithi Laoungbua, Orawan Khow, Lawan Chanhome, Visith Sitprija","doi":"10.1590/1678-9199-JVATITD-2023-0070","DOIUrl":"10.1590/1678-9199-JVATITD-2023-0070","url":null,"abstract":"<p><strong>Background: </strong>This study examines the direct nephrotoxic effects of <i>Daboia siamensis</i> venom (RVV) and venom fractions in <i>in vivo</i> and isolated perfused kidneys (IPK) to understand the role of inflammation pathways and susceptibility to oxidative stress in venom or fraction-induced acute renal failure.</p><p><strong>Methods: </strong>We administered RVV and its venom fractions (PLA₂, MP, LAAO, and PDE) to rabbits <i>in vivo</i> and in the IPK model. We measured oxidative stress biomarkers (SOD, CAT, GSH, and MDA) in kidney tissue, as well as inflammatory cytokines (TNF-α, IL-1β, IFN-γ, IL-4, IL-5, and IL-10), MDA and GSH levels in plasma and urine. We also calculated fractional excretion (FE) for pro-/anti-inflammatory cytokines and oxidative stress biomarkers, including the ratios of pro-/anti-inflammatory cytokines in urine after envenomation.</p><p><strong>Results: </strong>In both kidney models, significant increases in MDA, SOD, CAT, and GSH levels were observed in kidney tissues, along with elevated concentrations of MDA and GSH in plasma and urine after injecting RVV and venom fractions. Moreover, RVV injections led to progressive increases in FE_MDA and decreases in FE_GSH. The concentrations of IL-4, IL-5, IL-10, IFN-γ, and TNF-α in plasma increased <i>in vivo</i>, as well as in the urine of the IPK model, but not for IL-1β in both plasma and urine after RVV administrations. Urinary fractional excretion of TNF-α, IL-1β, IFN-γ, IL-4, IL-5, and IL-10 tended to decrease <i>in vivo</i> but showed elevated levels in the IPK model. A single RVV injection <i>in vivo</i> disrupted the balance of urinary cytokines, significantly reducing either the TNF-α/IL-10 ratio or the IFN-γ/IL-10 ratio.</p><p><strong>Conclusion: </strong>RVV induces renal tubular toxicity by increasing oxidative stress production and elevating inflammatory cytokines in urine. During the acute phase of acute kidney injury, the balance of urine cytokines shifts toward anti-inflammatory dominance within the first two hours post-RVV and venom fractions.</p>","PeriodicalId":17565,"journal":{"name":"Journal of Venomous Animals and Toxins Including Tropical Diseases","volume":"30 ","pages":"e20230070"},"PeriodicalIF":2.4,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11131233/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141161877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heterologous fibrin biopolymer as an emerging approach to peripheral nerve repair: a scoping review.","authors":"Kevin Silva Muller, Felipe Cantore Tibúrcio, Rui Seabra Ferreira, Benedito Barraviera, Selma Maria Michelin Matheus","doi":"10.1590/1678-9199-JVATITD-2023-0060","DOIUrl":"https://doi.org/10.1590/1678-9199-JVATITD-2023-0060","url":null,"abstract":"<p><p>Nerve injuries present a substantial challenge within the medical domain due to their prevalent occurrence and significant impact. In nerve injuries, a range of physiopathological and metabolic responses come into play to stabilize and repair the resulting damage. A critical concern arises from the disruption of connections at neuromuscular junctions, leading to profound degeneration and substantial loss of muscle function, thereby hampering motor tasks. While end-to-end neurorrhaphy serves as the established technique for treating peripheral nerve injuries, achieving comprehensive morphofunctional recovery remains a formidable challenge. In pursuit of enhancing the repair process, alternative and supportive methods are being explored. A promising candidate is the utilization of heterologous fibrin biopolymer, a sealant devoid of human blood components. Notably, this biopolymer has showcased its prowess in establishing a stable and protective microenvironment at the site of use in multiple scenarios of regenerative medicine. Hence, this scoping review is directed towards assessing the effects of associating heterologous fibrin biopolymer with neurorrhaphy to treat nerve injuries, drawing upon findings from prior studies disseminated through PubMed/MEDLINE, Scopus, and Web of Science databases. Further discourse delves into the intricacies of the biology of neuromuscular junctions, nerve injury pathophysiology, and the broader utilization of fibrin sealants in conjunction with sutures for nerve reconstruction procedures. The association of the heterologous fibrin biopolymer with neurorrhaphy emerges as a potential avenue for surmounting the limitations associated with traditional sealants while also mitigating degeneration in nerves, muscles, and NMJs post-injury, thereby fostering a more conducive environment for subsequent regeneration. Indeed, queries arise regarding the long-term regenerative potential of this approach and its applicability in reconstructive surgeries for human nerve injuries.</p>","PeriodicalId":17565,"journal":{"name":"Journal of Venomous Animals and Toxins Including Tropical Diseases","volume":"30 ","pages":"e20230060"},"PeriodicalIF":2.4,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11019597/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140853037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cytotoxic effects of crotoxin from <i>Crotalus durissus terrificus</i> snake in canine mammary tumor cell lines.","authors":"Giovana Pedro, Felipe César da Silva Brasileiro, Jamile Mariano Macedo, Andreimar Martins Soares, Gabriel Caporale Mafra, Carlos Eduardo Fonseca Alves, Renée Laufer-Amorim","doi":"10.1590/1678-9199-JVATITD-2023-0062","DOIUrl":"https://doi.org/10.1590/1678-9199-JVATITD-2023-0062","url":null,"abstract":"<p><strong>Background: </strong>Mammary gland tumors are the most prevalent neoplasm in intact female dogs, and they are good natural models to study comparative oncology. Most canine mammary malignancies, as in women, are commonly refractory to conventional therapies and demand continuous new therapeutic approaches. <i>Crotalus durissus terrificus</i>, also called rattlesnake, has more than 60 different proteins in its venom with multiple pharmaceutical uses, such as antitumor, antiviral, and antimicrobial action. Crotoxin, a potent β-neurotoxin formed by the junction of two subunits, a basic subunit (CB-PLA₂) and an acidic subunit (crotapotin), has already been reported to have anticancer properties in different types of cancers.</p><p><strong>Methods: </strong>In this work, we describe the cytotoxic potential of crotoxin and its subunits compared to doxorubicin (drug of choice) in two canine mammary carcinoma cell lines.</p><p><strong>Results: </strong>Crotoxin, CB-PLA₂, crotalic venom, and doxorubicin decreased cell viability and the ability to migrate in a dose-dependent manner, and crotapotin did not present an antitumoral effect. For all compounds, the predominant cell death mechanism was apoptosis. In addition, crotoxin did not show toxicity in normal canine mammary gland cells.</p><p><strong>Conclusion: </strong>Therefore, this work showed that crotoxin and CB-PLA₂ had cytotoxic activity, migration inhibition, and pro-apoptotic potential in canine mammary gland carcinoma cell lines, making their possible use in cancer research.</p>","PeriodicalId":17565,"journal":{"name":"Journal of Venomous Animals and Toxins Including Tropical Diseases","volume":"30 ","pages":"e20230062"},"PeriodicalIF":2.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10950368/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140175309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An overview of some enzymes from buthid scorpion venoms from Colombia: <i>Centruroides margaritatus, Tityus pachyurus,</i> and <i>Tityus</i> n. sp. aff. <i>metuendus</i>.","authors":"Leydy Lorena Mendoza-Tobar, Herlinda Clement, Iván Arenas, Juan Carlos Sepulveda-Arias, Jimmy Alexander Guerrero Vargas, Gerardo Corzo","doi":"10.1590/1678-9199-JVATITD-2023-0063","DOIUrl":"https://doi.org/10.1590/1678-9199-JVATITD-2023-0063","url":null,"abstract":"<p><strong>Background: </strong>In Colombia, several species of Buthidae scorpions belonging to the genera <i>Centruroides</i> and <i>Tityus</i> coexist, and their stings are considered life-threatening to humans because of their venom neurotoxins. Despite previous studies focusing on neurotoxins from these scorpion genera, little is known about the enzymes present in their venoms and their relationship with whole venom toxicity.</p><p><strong>Methods: </strong>Here, using proteomic and biochemical protocols the enzymatic activities of the venoms of three Colombian scorpion species, <i>C. margaritatus, T. pachyurus,</i> and <i>T.</i> n. sp. aff. <i>metuendus,</i> were compared to establish the presence and absence of enzymes such as phospholipases, hyaluronidases, and proteases that could be related to venom toxicity. <b>Results:</b> <i>C. margaritatus</i> was positive for hyaluronidases, <i>T.</i> n. sp. aff. <i>metuendus</i> for proteases, and <i>T. pachyurus</i> exhibited activity for all three mentioned enzymes.</p><p><strong>Conclusion: </strong>This information provides valuable insights into the specific enzyme diversity of each species' venom and their potential role in venom toxicity, which could contribute to the development of better treatments and prevention strategies for scorpion envenomation.</p>","PeriodicalId":17565,"journal":{"name":"Journal of Venomous Animals and Toxins Including Tropical Diseases","volume":"30 ","pages":"e20230063"},"PeriodicalIF":2.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10950367/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140175308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Skin secretions of Leptodactylidae (Anura) and their potential applications.","authors":"Juan F C Carrillo, Amanda Galdi Boaretto, Diego J Santana, Denise Brentan Silva","doi":"10.1590/1678-9199-JVATITD-2023-0042","DOIUrl":"10.1590/1678-9199-JVATITD-2023-0042","url":null,"abstract":"<p><p>The skin of anuran species is a protective barrier against predators and pathogens, showing also chemical defense by substances that represent a potential source for bioactive substances. This review describes the current chemical and biological knowledge from the skin secretions of Leptodactylidae species, one of the most diverse neotropical frog families. These skin secretions reveal a variety of substances such as amines (12), neuropeptides (16), and antimicrobial peptides (72). The amines include histamine and its methylated derivatives, tryptamine derivatives and quaternary amines. The peptides of Leptodactylidae species show molecular weight up to 3364 Da and ocellatins are the most reported. The peptides exhibit commonly glycine (G) or glycine-valine (GV) as C-terminal amino acids, and the most common N-terminal amino acids are glutamic acid (E), lysine (K), and valine (V). The substances from Leptodactylidae species have been evaluated against pathogenic microorganisms, particularly <i>Escherichia coli</i> and <i>Staphylococcus aureus</i>, and the most active peptides showed MIC of 1-15 µM. Furthermore, some compounds showed also pharmacological properties such as immunomodulation, treatment of degenerative diseases, anticancer, and antioxidant. Currently, only 9% of the species in this family have been properly studied, highlighting a large number of unstudied species such as an entire subfamily (Paratelmatobiinae). The ecological context, functions, and evolution of peptides and amines in this family are poorly understood and represent a large field for further exploration.</p>","PeriodicalId":17565,"journal":{"name":"Journal of Venomous Animals and Toxins Including Tropical Diseases","volume":"30 ","pages":"e20230042"},"PeriodicalIF":2.4,"publicationDate":"2024-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10876013/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139905950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Activation of M1 muscarinic acetylcholine receptors by proline-rich oligopeptide 7a (<EDGPIPP) from <i>Bothrops jararaca</i> snake venom rescues oxidative stress-induced neurotoxicity in PC12 cells.","authors":"Carlos Alberto-Silva, Halyne Queiroz Pantaleão, Brenda Rufino da Silva, Julio Cezar Araujo da Silva, Marcela Bermudez Echeverry","doi":"10.1590/1678-9199-JVATITD-2023-0043","DOIUrl":"10.1590/1678-9199-JVATITD-2023-0043","url":null,"abstract":"<p><strong>Background: </strong>The bioactive peptides derived from snake venoms of the Viperidae family species have been promising as therapeutic candidates for neuroprotection due to their ability to prevent neuronal cell loss, injury, and death. Therefore, this study aimed to evaluate the cytoprotective effects of a synthetic proline-rich oligopeptide 7a (PRO-7a; <EDGPIPP) from <i>Bothrops jararaca</i> snake, on oxidative stress-induced toxicity in neuronal PC12 cells and astrocyte-like C6 cells.</p><p><strong>Methods: </strong>Both cells were pre-treated for four hours with different concentrations of PRO-7a, submitted to H₂O₂-induced damage for 20 h, and then the oxidative stress markers were analyzed. Also, two independent neuroprotective mechanisms were investigated: a) L-arginine metabolite generation via argininosuccinate synthetase (AsS) activity regulation to produce agmatine or polyamines with neuroprotective properties; b) M1 mAChR receptor subtype activation pathway to reduce oxidative stress and neuron injury.</p><p><strong>Results: </strong>PRO-7a was not cytoprotective in C6 cells, but potentiated the H₂O₂-induced damage to cell integrity at a concentration lower than 0.38 μM. However, PRO-7a at 1.56 µM, on the other hand, modified H₂O₂-induced toxicity in PC12 cells by restoring cell integrity, mitochondrial metabolism, ROS generation, and arginase indirect activity. The α-Methyl-DL-aspartic acid (MDLA) and L-N^Ω-Nitroarginine methyl ester (L-Name), specific inhibitors of AsS and nitric oxide synthase (NOS), which catalyzes the synthesis of polyamines and NO from L-arginine, did not suppress PRO-7a-mediated cytoprotection against oxidative stress. It suggested that its mechanism is independent of the production of L-arginine metabolites with neuroprotective properties by increased AsS activity. On the other hand, the neuroprotective effect of PRO-7a was blocked in the presence of dicyclomine hydrochloride (DCH), an M1 mAChR antagonist.</p><p><strong>Conclusions: </strong>For the first time, this work provides evidence that PRO-7a-induced neuroprotection seems to be mediated through M1 mAChR activation in PC12 cells, which reduces oxidative stress independently of AsS activity and L-arginine bioavailability.</p>","PeriodicalId":17565,"journal":{"name":"Journal of Venomous Animals and Toxins Including Tropical Diseases","volume":"30 ","pages":"e20230043"},"PeriodicalIF":2.4,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10868729/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139741313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding the complexity of <i>Tityus serrulatus</i> venom: A focus on high molecular weight components.","authors":"Isadora Sousa de Oliveira, Nicoly Malachize Alano-da-Silva, Isabela Gobbo Ferreira, Felipe Augusto Cerni, Jacqueline de Almeida Gonçalves Sachett, Wuelton Marcelo Monteiro, Manuela Berto Pucca, Eliane Candiani Arantes","doi":"10.1590/1678-9199-JVATITD-2023-0046","DOIUrl":"10.1590/1678-9199-JVATITD-2023-0046","url":null,"abstract":"<p><p><i>Tityus serrulatus</i> scorpion is responsible for a significant number of envenomings in Brazil, ranging from mild to severe, and in some cases, leading to fatalities. While supportive care is the primary treatment modality, moderate and severe cases require antivenom administration despite potential limitations and adverse effects. The remarkable proliferation of <i>T. serrulatus</i> scorpions, attributed to their biology and asexual reproduction, contributes to a high incidence of envenomation. <i>T. serrulatus</i> scorpion venom predominantly consists of short proteins acting as neurotoxins (α and β), that primarily target ion channels. Nevertheless, high molecular weight compounds, including metalloproteases, serine proteases, phospholipases, and hyaluronidases, are also present in the venom. These compounds play a crucial role in envenomation, influencing the severity of symptoms and the spread of venom. This review endeavors to comprehensively understand the <i>T. serrulatus</i> scorpion venom by elucidating the primary high molecular weight compounds and exploring their potential contributions to envenomation. Understanding these compounds' mechanisms of action can aid in developing more effective treatments and prevention strategies, ultimately mitigating the impact of scorpion envenomation on public health in Brazil.</p>","PeriodicalId":17565,"journal":{"name":"Journal of Venomous Animals and Toxins Including Tropical Diseases","volume":"30 ","pages":"e20230046"},"PeriodicalIF":2.4,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10843179/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139692182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}