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Raquel Tonello, Camilla Fusi, Serena Materazzi, Ilaria M Marone, Francesco De Logu, Silvia Benemei, Muryel C Gonçalves, Elisabetta Coppi, Celio J Castro-Junior, Marcus Vinicius Gomez, Pierangelo Geppetti, Juliano Ferreira, Romina Nassini
BACKGROUND AND PURPOSE: Peptides from venomous animals have long been important tools for understanding pain mechanisms and for the discovery of pain treatments. Here, we hypothesized that Phα1β, a peptide purified from the armed spider Phoneutria nigriventer venom, produces analgesia by blocking the transient receptor potential ankyrin 1 (TRPA1) channel. EXPERIMENTAL APPROACH: Cultured rat dorsal root ganglion (DRG) neurons, human IMR90 fibroblasts or HEK293 cells expressing the human TRPA1 (hTRPA1-HEK293), TRPV1 (hTRPV1-HEK293) or TRPV4 (hTRPV4-HEK293), were used for calcium imaging and electrophysiology...
October 19, 2016: British Journal of Pharmacology
Mahfouz Ahmad Al-Agroudi, Salwa Abdalla Mohammad Ahmed, Tosson A Morsy
Spider bites are uncommon medical events, since there are limited number of spiders world-wide with fangs strong enough to pierce human skin, and most spiders bite humans only as a final defense when being crushed between skin and another object. Thus, most lesions attributed to spider bites are caused by some other etiology. The spiders that can cause medically significant bites include widow and false widow spiders (worldwide), recluse spiders (mostly North and South America), Australian funnel web spiders (eastern coastal Australia) and Phoneutria spiders (Brazil)...
April 2016: Journal of the Egyptian Society of Parasitology
Catarina Rapôso, Ulrika Björklund, Evanguedes Kalapothakis, Björn Biber, Maria Alice da Cruz-Höfling, Elisabeth Hansson
Bites from genus Phoneutria (Ctenidae, Araneomorpha) are the second most frequent source of spider accidents in Southeast Brazil. Severe envenoming from Phoneutria nigriventer produces vision disturbance, tremor and convulsion, suggesting that the CNS is involved; however, the mechanisms by which P. nigriventer venom (PNV) affects the CNS remain poorly understood. The present study aimed to investigate whether PNV directly impairs astrocytes. Cultured astrocytes were exposed to PNV, and intracellular Ca(2+) release and signaling were measured (Fura-2/AM), Na(+)/K(+)-ATPase and Toll-like receptor 4 (TLR4) involvement were investigated, actin filaments were stained (Alexa™ 488-conjugated phalloidin probe), the G-actin/F-actin ratio was determined, and the expression level of connexin 43 (Cx43) was assessed...
June 2016: Neurochemistry International
Bruna Luiza Emerich, Renata C M Ferreira, Marta N Cordeiro, Márcia Helena Borges, Adriano M C Pimenta, Suely G Figueiredo, Igor Dimitri G Duarte, Maria Elena de Lima
PnTx4(6-1), henceforth renamed δ-Ctenitoxin-Pn1a (δ-CNTX-Pn1a), a peptide from Phoneutria nigriventer spider venom, initially described as an insect toxin, binds to site 3 of sodium channels in nerve cord synaptosomes and slows down sodium current inactivation in isolated axons in cockroaches (Periplaneta americana). δ-CNTX-Pn1a does not cause any apparent toxicity to mice, when intracerebroventricularly injected (30 μg). In this study, we evaluated the antinociceptive effect of δ-CNTX-Pn1a in three animal pain models and investigated its mechanism of action in acute pain...
April 2016: Toxins
Edilene Siqueira Soares, Monique Culturato Padilha Mendonça, Thalita Rocha, Evanguedes Kalapothakis, Maria Alice da Cruz-Höfling
Upregulation of caveolin-3 (Cav-3) or connexin-43 (Cx43) in astrocytes has been associated with important brain pathologies. We used Phoneutria nigriventer spider venom (PNV), which induces blood-brain barrier breakdown in rats, in order to investigate Cav-3 and Cx43 expression in the cerebellum over critical periods of rat envenomation. By immunofluorescence, western blotting (WB), and transmission electron microscopy (TEM), we assessed changes at 1, 2, 5, 24, and 72 h post-venom. WB showed immediate increases in Cav-3 and Cx43 at 1 h (interval of greatest manifestations of envenomation) that persisted at 5 h (when there were signs of recovery) and peaked at 24 h when no signs of envenomation were detectable...
August 2016: Journal of Molecular Neuroscience: MN
Edilene Siqueira Soares, Monique Culturato Padilha Mendonça, Maria Alice da Cruz-Höfling
An important transcellular transport mechanism in the blood-brain barrier (BBB) involves caveolae, which are specialized delta-shaped domains of the endothelial plasma membrane that are rich in cholesterol, glycosphingolipids and the scaffolding protein Caveolina-1 (Cav-1). In this work, we investigated whether the increase in endocytosis and transendothelial vesicular trafficking in rat cerebellum after blood-brain barrier breakdown (BBBb) induced by Phoneutria nigriventer spider venom (PNV) was mediated by caveolae...
May 2016: Neurotoxicology
Sara M Oliveira, Cássia R Silva, Gabriela Trevisan, Jardel G Villarinho, Marta N Cordeiro, Michael Richardson, Márcia H Borges, Célio J Castro, Marcus V Gomez, Juliano Ferreira
The venom of the Brazilian armed spider Phoneutria nigriventer is a rich source of biologically active peptides that have potential as analgesic drugs. In this study, we investigated the analgesic and adverse effects of peptide 3-5 (Tx3-5), purified from P. nigriventer venom, in several mouse models of pain. Tx3-5 was administered by intrathecal injection to mice selected as models of postoperative (plantar incision), neuropathic (partial sciatic nerve ligation) and cancer-related pain (inoculation with melanoma cells) in animals that were either sensitive or tolerant to morphine...
May 2016: Pflügers Archiv: European Journal of Physiology
Tarcísio Liberato, Lanfranco Ranieri Paolo Troncone, Edson T Yamashiro, Solange M T Serrano, André Zelanis
Here we present a proteomic characterization of Phoneutria nigriventer venom. A shotgun proteomic approach allowed the identification, for the first time, of O-glycosyl hydrolases (chitinases) in P. nigriventer venom. The electrophoretic profiles under nonreducing and reducing conditions, and protein identification by mass spectrometry, indicated the presence of oligomeric toxin structures in the venom. Complementary proteomic approaches allowed for a qualitative and semi-quantitative profiling of P. nigriventer venom complexity, expanding its known venom proteome diversity...
March 2016: Amino Acids
Flavia R Silva, Edleusa M L Batista, Marcus V Gomez, Christopher Kushmerick, Juliana F Da Silva, Marta N Cordeiro, Luciene B Vieira, Fabiola M Ribeiro
Spider toxins are recognized as useful sources of bioactive substances, showing a wide range of pharmacological effects on neurotransmission. Several spider toxins have been identified biochemically and some of them are specific glutamate receptors antagonists. Previous data indicate that PnTx4-5-5, a toxin isolated from the spider Phoneutria nigriventer, inhibits the N-methyl-d-aspartate receptor (NMDAR), with little or no effect on AMPA, kainate or GABA receptors. In agreement with these results, our findings in this study show that PnTx4-5-5 reduces the amplitude of NMDAR-mediated EPSCs in hippocampal slices...
March 15, 2016: Toxicon: Official Journal of the International Society on Toxinology
Ana L B Paiva, Alessandra Matavel, Steve Peigneur, Marta N Cordeiro, Jan Tytgat, Marcelo R V Diniz, Maria Elena de Lima
The toxin PnTx4(5-5) from the spider Phoneutria nigriventer is extremely toxic/lethal to insects but has no macroscopic behavioral effects observed in mice after intracerebral injection. Nevertheless, it was demonstrated that it inhibits the N-methyl-d-aspartate (NMDA) - subtype of glutamate receptors of cultured rat hippocampal neurons. PnTx4(5-5) has 63% identity to PnTx4(6-1), another insecticidal toxin from P. nigriventer, which can slow down the sodium current inactivation in insect central nervous system, but has no effect on Nav1...
February 2016: Biochimie
Juliana Figueira da Silva, Célio José Castro-Junior, Sara Marchesan Oliveira, Gerusa Duarte Dalmolin, Cássia Regina Silva, Luciene Bruno Vieira, Danuza Montijo Diniz, Marta do Nascimento Cordeiro, Juliano Ferreira, Alessandra Hubner Souza, Marcus Vinícius Gomez
Venom-derived peptides constitute a unique source of drug prototypes for the pain management. Many of them can modulate voltage-gated calcium channels that are central in the processing of pain sensation. PhTx3-4 is a peptide isolated from Phoneutria nigriventer venom, which blocks high voltage-activated calcium channels with low specificity, thereby leading to neuroprotection in models of ischemia in vitro. The aim of the present work was evaluating the potential of intrathecal PhTx3-4 in the reversal of different nociceptive states in mice, furthermore assessing the potential of PhTx3-4 in triggering motor side effects...
December 15, 2015: Toxicon: Official Journal of the International Society on Toxinology
Richard S Vetter, Rodney L Crawford, Donald J Buckle
Spiders found in international cargo brought into North America are sometimes submitted to arachnologists for identification. Often, these spiders are presumed to be of medical importance because of size or a submitter's familiarity with a toxic spider genus from the continent of origin. Starting in 2006, requests were made for spiders found in international cargo brought into North America, in addition to the specimens from similar cargo shipments already in our museum collections. This was an ad hoc study that allowed us to focus on spiders of concern to the discoverer...
November 1, 2014: Journal of Medical Entomology
Sebastian Estrada-Gomez, Leidy Johana Vargas Muñoz, Paula Lanchero, Cesar Segura Latorre
We report on the first studies on the characterization of venom from Phoneutria boliviensis (Aranae:Ctenidae) (F. O. Pickard-Cambridge, 1897), done with Colombian species. After the electrostimulation extraction process, the venom showed physicochemical properties corresponding to a colorless and water-soluble liquid with a density of 0.86 mg/mL and 87% aqueous content. P. boliviensis venom and RP-HPLC fractions showed hemolytic activity and hydrolyzed the synthetic substrate 4-nitro-3-octanoyloxy-benzoic acid, indicating the presence of phospholipases A2 enzymes...
August 2015: Toxins
Leida Calegário de Oliveira, Fabiana V Campos, Suely Gomes Figueiredo, Marta N Cordeiro, Beatriz R Adaime, Michael Richardson, Adriano M C Pimenta, Marie-France Martin-Eauclaire, Paulo S L Beirão, Maria Elena De Lima
A potent insecticidal toxin, β/δ-PrIT1, molecular mass of 5598.86 [M+H](+), was characterized from Phoneutria reidyi spider venom. Its partial amino acid sequence showed high similarity with insecticidal spider toxins from the genus Phoneutria. β/δ-PrIT1 was very toxic (LD50 = 4 nmol/g) to flies (Musca domestica), but not to mice (Mus musculus). Kinetic studies showed that (125)I-β/δ-PrIT1 binds to two distinct sites in insect sodium channels, with close affinity (Kd1 = 34.7 pM and Kd2 = 35.1 pM). Its association is rather fast (t1/2(1) = 1...
September 15, 2015: Toxicon: Official Journal of the International Society on Toxinology
Edilene Siqueira Soares, Monique Culturato Padilha Mendonça, Maria Alice da Cruz-Höfling
Numerous studies have shown that the venom of Phoneutria nigriventer (PNV) armed-spider causes excitotoxic signals and blood-brain barrier breakdown (BBBb) in rats. Nitric oxide (NO) is a signaling molecule which has a role in endothelium homeostasis and vascular health. The present study investigated the relevance of endothelial NO synthase (eNOS) uncoupling to clinical neurotoxic evolution induced by PNV. eNOS immunoblotting of cerebellum lysates processed through low-temperature SDS-PAGE revealed significant increased monomerization of the enzyme at critical periods of severe envenoming (1-2 h), whereas eNOS dimerization reversal paralleled to amelioration of animals condition (5-72 h)...
September 15, 2015: Toxicon: Official Journal of the International Society on Toxinology
Carolina Nunes Silva, Kenia Pedrosa Nunes, Fernanda Silva Torres, Juliana Silva Cassoli, Daniel Moreira Santos, Flávia De Marco Almeida, Alessandra Matavel, Jader Santos Cruz, Arthur Santos-Miranda, Allancer Divino C Nunes, Carlos Henrique Castro, Ricardo Andrés Machado de Ávila, Carlos Chávez-Olórtegui, Stephanie Stransky Láuar, Liza Felicori, Jarbas Magalhães Resende, Elizabeth Ribeiro da Silva Camargos, Márcia Helena Borges, Marta Nascimento Cordeiro, Steve Peigneur, Jan Tytgat, Maria Elena de Lima
PURPOSE: We designed a peptide, PnPP-19, comprising the potential active core of the Phoneutria nigriventer native toxin PnTx2-6. We investigated its role on erectile function, and its toxicity and immunogenicity. MATERIALS AND METHODS: Erectile function was evaluated by the intracavernous pressure-to-mean arterial pressure ratio during electrical field stimulation on rat pelvic ganglia. Cavernous strips were contracted with phenylephrine and relaxation was induced by electrical field stimulation with or without PnPP-19 (10(-8) M)...
November 2015: Journal of Urology
Flávia De Marco Almeida, Adriano Monteiro de Castro Pimenta, Mônica Cristina Oliveira, Maria Elena De Lima
Animal venoms have been widely investigated throughout the world. The great number of biotechnological articles as well as patent applications in the field of drug discovery based on these compounds indicates how important the source is. This review presents a list of the most studied Brazilian venomous animal species and shows the most recent patent applications filed from 2000 to 2013, which comprise Brazilian venoms, toxins and derivatives. We analyze the data according to the species, the type of products claimed and the nationality of the inventors...
June 25, 2015: Sheng Li Xue Bao: [Acta Physiologica Sinica]
Sylvia M Lucas
The article provides a historical report on venomous spider identification, venom obtainment methods and serum production at the Butantan Institute, São Paulo, Brazil. It is based on literature and personnal experience during the last 50 years. This result is the discovery that the real species causing potential severe human accidents were the spiders of the genus Loxosceles and Phoneutria.
2015: Journal of Venomous Animals and Toxins Including Tropical Diseases
Monique C P Mendonça, Edilene S Soares, Leila M Stávale, Evanguedes Kalapothakis, Maria Alice Cruz-Höfling
Phoneutria nigriventer spider accidental envenomation provokes neurotoxic manifestations, which when critical, results in epileptic-like episodes. In rats, P. nigriventer venom (PNV) causes blood-brain barrier breakdown (BBBb). The PNV-induced excitotoxicity results from disturbances on Na(+), K(+) and Ca(2+) channels and glutamate handling. The vascular endothelial growth factor (VEGF), beyond its angiogenic effect, also, interferes on synaptic physiology by affecting the same ion channels and protects neurons from excitotoxicity...
2014: BioMed Research International
Catarina Rapôso, Paulo Alexandre Miranda Odorissi, Stefania Fioravanti Savioli, Rafaela Chitarra Rodrigues Hell, Gustavo Ferreira Simões, Roberta R Ruela-de-Sousa, Alexandre Leite Rodrigues de Oliveira, Maria Alice da Cruz-Höfling
Severe accidents caused by the "armed" spider Phoneutria nigriventer cause neurotoxic manifestations in victims. In experiments with rats, P. nigriventer venom (PNV) temporarily disrupts the properties of the BBB by affecting both the transcellular and the paracellular route. However, it is unclear how cells and/or proteins participate in the transient opening of the BBB. The present study demonstrates that PNV is a substrate for the multidrug resistance protein-1 (MRP1) in cultured astrocyte and endothelial cells (HUVEC) and increases mrp1 and cx43 and down-regulates glut1 mRNA transcripts in cultured astrocytes...
2014: PloS One
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