The Venom Composition of the Snake Tribe Philodryadini: 'Omic' Techniques Reveal Intergeneric Variability among South American Racers.

Snakes of the Philodryadini tribe are included in the Dipsadidae family, which is a diverse group of rear-fanged snakes widespread in different ecological conditions, including habitats and diet. However, little is known about the composition and effects of their venoms despite their relevance for understanding the evolution of these snakes or even their impact on the occasional cases of human envenoming. In this study, we integrated venom gland transcriptomics, venom proteomics and functional assays to characterize the venoms from eight species of the Philodryadini tribe, which includes the genus Philodryas, Chlorosoma and Xenoxybelis. The most abundant components identified in the venoms were snake venom metalloproteinases (SVMPs), cysteine-rich secretory proteins (CRISPs), C-type lectins (CTLs), snake endogenous matrix metalloproteinases type 9 (seMMP-9) and snake venom serinoproteinases (SVSPs). These protein families showed a variable expression profile in each genus. SVMPs were the most abundant components in Philodryas, while seMMP-9 and CRISPs were the most expressed in Chlorosoma and Xenoxybelis, respectively. Lineage-specific differences in venom composition were also observed among Philodryas species, whereas P. olfersii presented the highest amount of SVSPs and P. agassizii was the only species to express significant amounts of 3FTx. The variability observed in venom composition was confirmed by the venom functional assays. Philodryas species presented the highest SVMP activity, whereas Chlorosoma species showed higher levels of gelatin activity, which may correlate to the seMMP-9 enzymes. The variability observed in the composition of these venoms may be related to the tribe phylogeny and influenced by their diets. In the presented study, we expanded the set of venomics studies of the Philodryadini tribe, which paves new roads for further studies on the evolution and ecology of Dipsadidae snakes.

The venom composition of the snake tribe Philodryadini: ‘Omic’ techniques reveal intergeneric variability among South American racers

Snakes of the Philodryadini tribe are included in the Dipsadidae family, which is a diverse group of rear-fanged snakes widespread in different ecological conditions, including habitats and diet. However, little is known about the composition and effects of their venoms despite their relevance for understanding the evolution of these snakes or even their impact on the occasional cases of human envenoming. In this study, we integrated venom gland transcriptomics, venom proteomics and functional assays to characterize the venoms from eight species of the Philodryadini tribe, which includes the genus Philodryas, Chlorosoma and Xenoxybelis. The most abundant components identified in the venoms were snake venom metalloproteinases (SVMPs), cysteine-rich secretory proteins (CRISPs), C-type lectins (CTLs), snake endogenous matrix metalloproteinases type 9 (seMMP-9) and snake venom serinoproteinases (SVSPs). These protein families showed a variable expression profile in each genus. SVMPs were the most abundant components in Philodryas, while seMMP-9 and CRISPs were the most expressed in Chlorosoma and Xenoxybelis, respectively. Lineage-specific differences in venom composition were also observed among Philodryas species, whereas P. olfersii presented the highest amount of SVSPs and P. agassizii was the only species to express significant amounts of 3FTx. The variability observed in venom composition was confirmed by the venom functional assays. Philodryas species presented the highest SVMP activity, whereas Chlorosoma species showed higher levels of gelatin activity, which may correlate to the seMMP-9 enzymes. The variability observed in the composition of these venoms may be related to the tribe phylogeny and influenced by their diets. In the presented study, we expanded the set of venomics studies of the Philodryadini tribe, which paves new roads for further studies on the evolution and ecology of Dipsadidae snakes.

Análise bioquímica do veneno da serpente Philodryas patagoniensis: caracterização preliminar de uma calicreína-símile

The snakebite is considered a worldwide public health concern that is constantly neglected as it occurs, essentially, in regions of Africa, Asia and Latin America. As these accidents usually happen in countries that are emerging or underdeveloped, the incidence and mortality data end up not being accurate due to the lack of proper notification. In addition, the affected patient often may not receive adequate treatment due to the difficulty in identifying the snake and having access to serum therapy. Snakes can be found throughout Brazilian territory, and snakes are quite common in the country. Among the genera that can be found in the country, it is included in the genus Philodryas, which has some species of snakes, among them is Philodryas patagoniensis. The envenomation by this snake, generally, does not evolve into a serious clinical condition. However, its venom generates edematogenic and hemorrhagic activity, in addition to pain and tissue damage in the injured area, which causes cases of poisoning by this snake to be mistaken for the snake-like accident by Bothrops. In relation to the toxins present in this snake's venom, its composition, biological function and physiological activities are still unclarified. Therefore, the aim of this work is to investigate the composition of the species' venom with regard to the evaluation of a possible release of kinins from the KN-BK substrate by the venom of this snake. Kinins are released by kallikrein, which could indicate a similar kallikrein present in Philodryas patagoniensis venom that would be precisely involved in the process of releasing bradykinin, an inflammatory mediator. This kallikrein-simile contributes to the triggering of clinical manifestations such as pain and edema caused by the poisoning of this snake.

O acidente ofídico é considerado um problema de saúde pública mundial, constantemente negligenciado por ocorrer, essencialmente, em regiões da África, Ásia e América Latina. Pelo fato de os acidentes acontecerem geralmente em países que são emergentes ou subdesenvolvidos, os dados de incidência e mortalidade acabam não sendo precisos pela falta da notificação apropriada. Além disso, o paciente acometido, muitas vezes, pode não receber o tratamento adequado pela dificuldade na identificação da serpente e ao acesso a soroterapia. As serpentes podem ser amplamente encontradas em todo território brasileiro, sendo o ofidismo bastante comum no país. Em meio aos gêneros que podem ser encontrados no país, está incluído o gênero Philodryas, que possui algumas espécies de serpentes, dentre elas, a Philodryas patagoniensis. O envenenamento por esta serpente, geralmente não evolui para um quadro clínico grave. No entanto, seu veneno gera atividade edematogênica e hemorrágica além de dor e dano tecidual no local lesado, o que faz com que os casos de envenenamento por essa serpente sejam confundidos com o acidente ofídico causados por serpentes do gênero Bothrops. Em relação às toxinas presentes no veneno dessa serpente, sua composição, função biológica e atividades fisiológicas ainda não são esclarecidas. Diante disto, o intuito deste trabalho é investigar a composição do veneno da espécie no que diz respeito à avaliação de uma possível liberação de cininas do substrato KN-BK pelo veneno dessa serpente. As cininas são liberadas pelas calicreínas plasmática e teciduais humanas e são peptídeos bioativos com funções na regulação da pressão arterial e participação em processos inflamatórios. Assim, a observação de uma calicreína-símile presente no veneno de Philodryas patagoniensis poderia estar envolvida no desencadeamento das manifestações clínicas como a dor e o edema acarretadas pelo envenenamento desta serpente.

The Influence of Silver Nanoparticles Against Toxic Effects of Philodryas olfersii Venom.

PURPOSE: A silver nanoparticle obtained by reducing salts with solid dispersion of curcumin (130 nm, 0.081 mg mL-1) was used to counteract against the toxic - edematogenic, myotoxic, and neurotoxic - effects of Philodryas olfersii venom. METHODS: The edematogenic effect was evaluated by plasma extravasation in rat dorsal skin after injection of 50 µg per site of venom alone or preincubated with 1, 10, and 100 µL of AgNPs; the myotoxicity was evaluated by measuring the creatine kinase released into the organ-bath before the treatment and at the end of each experiment; and neurotoxicity was evaluated in chick biventer cervicis using the conventional myographic technique, face to the exogenous acetylcholine (ACh) and potassium chloride (KCl) added into the bath before the treatment and after each experiment. Preliminarily, a concentration-response curve of AgNPs was carried out to select the concentration to be used for neutralizing assays, which consists of neutralizing the venom-induced neuromuscular paralysis and edema by preincubating AgNPs with venom for 30 min. RESULTS: The P. olfersii venom-induced edema (n=6) and a complete neuromuscular blockade (n=4) that includes the total and unrecovered block of ACh and KCl contractures. AgNPs produced a concentration-dependent decrease the venom-induced edema (n=6) from 223.3% to 134.4% and to 100.5% after 10 and 100 µL AgNPs-preincubation, respectively. The preincubation of venom with AgNPs (1 µL; n=6) was able to maintain 46.5 ± 10.9% of neuromuscular response under indirect stimuli, 39.2 ± 9.7% of extrinsic nicotinic receptors functioning in absence of electrical stimulus and 28.3 ± 8.1% of responsiveness to potassium on the sarcolemmal membrane. The CK release was not affected by any experimental protocol which was like control. CONCLUSION: AgNPs interact with constituents of P. olfersii venom responsible for the edema-forming activity and neuromuscular blockade, but not on the sarcolemma membrane-acting constituents. The protective effect of the studied AgNPs on avian preparation points out to molecular targets as intrinsic and extrinsic nicotinic receptors.

Bites by Philodryas olfersii (Lichtenstein, 1823) and Philodryas aestiva (Duméril, Bibron and Duméril, 1854) (serpentes, dipsadidae) in São Paulo, Brazil: A retrospective observational study of 155 cases.

Despite the biological relevance and abundance of non-front-fanged colubroid snakes, little is known about the medical significance of the majority these species. Herein, we described bites by two green racer species of colubroid snakes, with respect to clinical, epidemiological, and biological features. We retrospectively analyzed proven cases of Philodryas olfersii and Philodryas aestiva bites. Only cases in which the causative animal was brought and identified by an expert were included. Analysis included variables related to the snake, patient demographics, clinical findings, whole blood clotting time (WBCT20), and treatments. Total 155 medical records were analyzed, of which 141 and 14 patients each were bitten by P. olfersii and P. aestiva, respectively. Most bites occurred in spring and summer seasons, predominantly during daytime. Most snakes were female and adult. Bites by P. olfersii adults were more frequent in summer (p < 0.001) and spring (p < 0.001). The hands were most frequently bitten by P. olfersii (59.6%), while the feet and legs (71.4%) were most bitten by P. aestiva. The most common local signs or symptoms observed were pain, edema, erythema, and transitory local bleeding. Severe pain, extensive edema, ecchymosis, and paresthesia were present only in patients bitten by P. olfersii. Significant association was observed between local bleeding and adult snakes (p = 0.019), as well as between the snout-vent-length and pain (p = 0.018), extensive edema (p = 0.024), and erythema (p = 0.047). WBCT20 was normal in the 35 cases in which it was available. Two patients were wrongly treated with anti-Bothrops antivenom. These results indicated that most accidents caused by P. olfersii and P. aestiva present mild local symptomatology. Some bites of P. olfersii bites may present local symptoms, resembling bites by Bothrops-like snakes. Physicians should be informed about these kinds of accidents, to avoid unnecessary distress to the patient and over prescription of antivenom.

Bites by Philodryas olfersii (Lichtenstein, 1823) and Philodryas aestiva (Duméril, Bibron and Duméril, 1854) (serpentes, dipsadidae) in São Paulo, Brazil: a retrospective observational study of 155 cases

Despite the biological relevance and abundance of non-front-fanged colubroid snakes, little is known about the medical significance of the majority these species. Herein, we described bites by two green racer species of colubroid snakes, with respect to clinical, epidemiological, and biological features. We retrospectively analyzed proven cases of Philodryas olfersii and Philodryas aestiva bites. Only cases in which the causative animal was brought and identified by an expert were included. Analysis included variables related to the snake, patient demographics, clinical findings, whole blood clotting time (WBCT20), and treatments. Total 155 medical records were analyzed, of which 141 and 14 patients each were bitten by P. olfersii and P. aestiva, respectively. Most bites occurred in spring and summer seasons, predominantly during daytime. Most snakes were female and adult. Bites by P. olfersii adults were more frequent in summer (p < 0.001) and spring (p < 0.001). The hands were most frequently bitten by P. olfersii (59.6%), while the feet and legs (71.4%) were most bitten by P. aestiva. The most common local signs or symptoms observed were pain, edema, erythema, and transitory local bleeding. Severe pain, extensive edema, ecchymosis, and paresthesia were present only in patients bitten by P. olfersii. Significant association was observed between local bleeding and adult snakes (p = 0.019), as well as between the snout-vent-length and pain (p = 0.018), extensive edema (p = 0.024), and erythema (p = 0.047). WBCT20 was normal in the 35 cases in which it was available. Two patients were wrongly treated with anti-Bothrops antivenom. These results indicated that most accidents caused by P. olfersii and P. aestiva present mild local symptomatology. Some bites of P. olfersii bites may present local symptoms, resembling bites by Bothrops-like snakes. Physicians should be informed about these kinds of accidents, to avoid unnecessary distress to the patient and over prescription of antivenom.

Molecular phylogeny of the tribe Philodryadini Cope, 1886 (Dipsadidae: Xenodontinae): Rediscovering the diversity of the South American Racers

South American racers of the tribe Philodryadini are a widespread and diverse group of Neotropical snakes with a complex taxonomic and systematic history. Recent studies failed to present a robust phylogenetic hypothesis for the tribe, mainly due to incomplete taxon sampling. Here we provide the most extensive molecular phylogenetic analysis of Philodryadini available so far, including 20 species (83% of the known diversity) from which six were not sampled previously. Our results reveal that Philodryadini is not monophyletic, but instead includes a central Andean clade formed by Philodryas simonsii, P. tachymenoides, and P. amaru, and a southern and cis-Andean clade including all remaining philodryadines. This discovery requires resurrection of two genera as well as erection of a new tribe of Xenodontinae for the central Andean clade. Within the southern and cis-Andean radiation, our analyses resolve a basal dichotomy separating two main lineages: Clade A, containing the Common Green Racers P. laticeps and P. viridissima and the South American Vine snakes P. georgeboulengeri and P. argentea; and Clade B, including the remaining species of Philodryas sensu stricto. We resurrect the genera Chlorosoma and Xenoxybelis to better represent the monophyly of lineages within the southern and cis-Andean clade.(AU)

Molecular phylogeny of the tribe Philodryadini Cope, 1886 (Dipsadidae: Xenodontinae): Rediscovering the diversity of the South American Racers

South American racers of the tribe Philodryadini are a widespread and diverse group of Neotropical snakes with a complex taxonomic and systematic history. Recent studies failed to present a robust phylogenetic hypothesis for the tribe, mainly due to incomplete taxon sampling. Here we provide the most extensive molecular phylogenetic analysis of Philodryadini available so far, including 20 species (83% of the known diversity) from which six were not sampled previously. Our results reveal that Philodryadini is not monophyletic, but instead includes a central Andean clade formed by Philodryas simonsii, P. tachymenoides, and P. amaru, and a southern and cis-Andean clade including all remaining philodryadines. This discovery requires resurrection of two genera as well as erection of a new tribe of Xenodontinae for the central Andean clade. Within the southern and cis-Andean radiation, our analyses resolve a basal dichotomy separating two main lineages: Clade A, containing the Common Green Racers P. laticeps and P. viridissima and the South American Vine snakes P. georgeboulengeri and P. argentea; and Clade B, including the remaining species of Philodryas sensu stricto. We resurrect the genera Chlorosoma and Xenoxybelis to better represent the monophyly of lineages within the southern and cis-Andean clade.

Molecular phylogeny of the tribe Philodryadini Cope, 1886 (Dipsadidae: Xenodontinae): Rediscovering the diversity of the South American Racers

Abstract South American racers of the tribe Philodryadini are a widespread and diverse group of Neotropical snakes with a complex taxonomic and systematic history. Recent studies failed to present a robust phylogenetic hypothesis for the tribe, mainly due to incomplete taxon sampling. Here we provide the most extensive molecular phylogenetic analysis of Philodryadini available so far, including 20 species (83% of the known diversity) from which six were not sampled previously. Our results reveal that Philodryadini is not monophyletic, but instead includes a central Andean clade formed by Philodryas simonsii, P. tachymenoides, and P. amaru, and a southern and cis-Andean clade including all remaining philodryadines. This discovery requires resurrection of two genera as well as erection of a new tribe of Xenodontinae for the central Andean clade. Within the southern and cis-Andean radiation, our analyses resolve a basal dichotomy separating two main lineages: Clade A, containing the Common Green Racers P. laticeps and P. viridissima and the South American Vine snakes P. georgeboulengeri and P. argentea; and Clade B, including the remaining species of Philodryas sensu stricto. We resurrect the genera Chlorosoma and Xenoxybelis to better represent the monophyly of lineages within the southern and cis-Andean clade.

Phylogenetic analysis of Hepatozoon spp. (Apicomplexa: Hepatozoidae) infecting Philodryas patagoniensis (Serpentes: Dipsadidae) in Uruguay.

The purpose of this study was to perform a phylogenetic analysis of Hepatozoon spp. infecting Philodryas patagoniensis in Uruguay. Twenty-five road-killed specimens of P. patagoniensis from ten departments were obtained. Samples of blood and/or heart tissue were taken. Polymerase chain reaction (PCR) assay was carried out amplifying a specific target region of the 18S rRNA gene of Hepatozoon spp. Eighteen out of twenty-five samples were positive to Hepatozoon spp., which gave an overall prevalence of 72%. Phylogenetic analyses with the obtained sequences were carried out to determine the relationship with closely related species found in the region. The results revealed that samples were split into two clades with a high bootstrap support. Clade I was formed with Hepatozoon spp. sequences obtained in this study from P. patagoniensis, Hepatozoon cuestensis from Crotalus durissus terrificus and Hepatozoon musa from Philodryas nattereri, and Hepatozoon spp. retrieved from Cerdocyon thous, Hemidactylus mabouia, and Phyllopezus pollicaris from Brazil, respectively. Clade II was grouped with Hepatozoon cevapii and Hepatozoon massardii, both species described for C. d. terrificus from Brazil. This is the first report of Hepatozoon spp. in snakes from Uruguay.

Philodryas (Serpentes: Dipsadidae) Envenomation, a Neglected Issue in Chile.

Snakebite envenomation is considered a neglected tropical disease, although it also occurs outside the tropics. In this work, we analyzed the literature on Philodryas species in Chile (Philodryaschamissonis, P.simonsii, and P.tachymenoides) from 1834 to 2019, searching for epidemiological, clinical, and molecular aspects of envenomation. Ninety-one percent of the studies found regarded taxonomy, ecology, and natural history, suggesting that snakebites and venom toxins are a neglected issue in Chile. All snakebite cases reported and toxicological studies concerned the species Philodryaschamissonis. Using 185 distributional records from the literature and museum collections for this species, we show for the first time that the reported snakebite cases correlate with human population density, occurring in the Valparaiso and Metropolitan regions in Central Chile. The reduced number of snakebite cases, which were previously considered as having a low incidence in Chile, may be a consequence of under-reported cases, probably due to the inadequate publication or scarce research on this issue. Absence of information about official pharmacological treatment, post-envenoming sequels, clinical management of particular patient groups (e.g., with non-communicable diseases, pregnant women, and the elderly) was also detected. In conclusion, despite having over 185 years of literature on Chilean snakes, knowledge on the envenomation of Philodryas genus remains scarce, seriously affecting adequate medical handling during an ophidic accident. This review highlights the need to develop deep research in this area and urgent improvements to the management of this disease in Chile.

Occurrence of Dioctophyme renale larvae (Goeze, 1782) (Nematoda: Enoplida) in a new host from southern Brazil / Novo hospedeiro de larvas de Dioctophyme renale (Goeze, 1782) (Nematoda: Enoplida) no extremo sul do Brasil

Dioctophymatosis is caused by the giant kidney worm Dioctophyme renale which occurs in dogs, cats, and wild mammals. In Brazil, the disease has been diagnosed in dogs from several states around the country. In the present study, the occurrence of D. renale larvae in snakes from southern of Brazil is reported. Three specimens of Philodryas patagoniensis (Serpentes: Dipsadidae) (common names in Brazil: parelheira, papa-pinto) roadkill in the county of Capão do Leão, State of Rio Grande do Sul, southern Brazil, were necropsied. Two third-stage larvae of D. renale were found in the coelomic cavity of P. patagoniensis. This study reveals a new host for D. renale larvae in the southern region of the State of Rio Grande do Sul, Brazil. This particular geographic area of the country has stood out as several cases of D. renale infection have been reported in a number of vertebrates from this region including domestic dogs and cats and wild animals such as carnivores, fish, and freshwater turtles.(AU)

Dioctophyme renale, verme gigante do rim, parasita cães, gatos e mamíferos silvestres, sendo que no Brasil, a dioctofimatose canina vem sendo diagnosticada em diversos estados brasileiros. O estudo tem por objetivo registrar larvas de D. renale parasitando serpente no extremo sul do Brasil. Nesse contexto, foram examinados três espécimes de Philodryas patagoniensis (Serpentes: Dipsadidae) encontradas mortas após atropelamento em uma estrada do município de Capão do Leão, Rio Grande do Sul (RS). Duas larvas de terceiro estágio de D. renale foram encontradas na cavidade celomática de P. patagoniensis, a qual representa um novo hospedeiro para larvas de D. renale na região sul do RS, a qual vem se destacando devido aos diversos registros do parasito em cães e gatos domésticos, bem como animais silvestres (carnívoros, peixes, quelônios).(AU)

Occurrence of Dioctophyme renale larvae (Goeze, 1782) (Nematoda: Enoplida) in a new host from southern Brazil / Novo hospedeiro de larvas de Dioctophyme renale (Goeze, 1782) (Nematoda: Enoplida) no extremo sul do Brasil

Abstract Dioctophymatosis is caused by the giant kidney worm Dioctophyme renale which occurs in dogs, cats, and wild mammals. In Brazil, the disease has been diagnosed in dogs from several states around the country. In the present study, the occurrence of D. renale larvae in snakes from southern of Brazil is reported. Three specimens of Philodryas patagoniensis (Serpentes: Dipsadidae) (common names in Brazil: "parelheira", "papa-pinto") roadkill in the county of Capão do Leão, State of Rio Grande do Sul, southern Brazil, were necropsied. Two third-stage larvae of D. renale were found in the coelomic cavity of P. patagoniensis. This study reveals a new host for D. renale larvae in the southern region of the State of Rio Grande do Sul, Brazil. This particular geographic area of the country has stood out as several cases of D. renale infection have been reported in a number of vertebrates from this region including domestic dogs and cats and wild animals such as carnivores, fish, and freshwater turtles.

Resumo Dioctophyme renale, verme gigante do rim, parasita cães, gatos e mamíferos silvestres, sendo que no Brasil, a dioctofimatose canina vem sendo diagnosticada em diversos estados brasileiros. O estudo tem por objetivo registrar larvas de D. renale parasitando serpente no extremo sul do Brasil. Nesse contexto, foram examinados três espécimes de Philodryas patagoniensis (Serpentes: Dipsadidae) encontradas mortas após atropelamento em uma estrada do município de Capão do Leão, Rio Grande do Sul (RS). Duas larvas de terceiro estágio de D. renale foram encontradas na cavidade celomática de P. patagoniensis, a qual representa um novo hospedeiro para larvas de D. renale na região sul do RS, a qual vem se destacando devido aos diversos registros do parasito em cães e gatos domésticos, bem como animais silvestres (carnívoros, peixes, quelônios).

Envenomations by colubrids: case reports

Introduction: Envenomations by non-venomous snakes in Brazil are poorly accounted for and classified as mild, in which pain, erythema and local edema are reported. Objective: To describe accidents by Philodryas olfersii and Hydrodynastes gigas that occurred in the State of Pará, Brazil. Case report: The patient bitten by Philodryas presented bleeding, pain, local edema and axillary adenopathy. The patient bitten by Hydrodynastes had pain, local growing edema, as well as ecchymosis, fever and headache. No laboratory tests were performed. The treatment was based on pain control after identification of the snakes. Conclusion: The local symptomatology of colubrids is similar to accidents with Bothrops. It is important that health professionals perform a correct diagnosis for proper treatment.

Comparing the antipredator behaviour of two sympatric, but not syntopic, Liolaemus lizards.

The microhabitat preferences of prey animals can modulate how they perceive predation risk, and therefore, their antipredator behaviour. We tested under standardized conditions how microhabitat preferences of two Liolaemus lizards affected their responses when confronted with two types of ambush predators (raptor vs. snake), under two levels of predation risk (low vs. high). These lizard species are sympatric, but not syntopic; L. chiliensis basks on bushes, a complex microhabitat that may provide protection against visual predators, while L. nitidus prefers open microhabitats, basking on the top of large bare rocks, highly exposed to visual predators. If microhabitat complexity modulates the antipredator response, L. chiliensis may perceive lower predation risk, exhibiting lower intensity of antipredator responses than L. nitidus. Both species reduced their activity after being exposed to both predators, but lizards differed in the assessment of predation risk; L. nitidus reduced its activity independently of the predation risk experienced, while L. chiliensis only reduced its activity in the high-risk condition. The microhabitat preferences shaped during the evolution of these species seem to modulate their perception of predation risk, which may cause interspecific differences in the associated costs of their antipredator responses.

Alterações morfológicas de pele de camundongos inoculados com o veneno total da serpente Philodryas nattereri / Morphological alterations in mice skins inoculated with the total snake venom of Philodryas nattereri / Las alteraciones morfológicas en la piel de ratones causadas por el veneno de la serpiente Philodryas nattereri

Venenos de serpentes são compostos por substâncias ativas complexas, sendo a maioria delas de natureza proteica, causando diversos efeitos no ser humano e animais domésticos podendo levar ao óbito. Philodryas nattereri é uma serpente nativa da região do Ceará, sendo encontrada em todo o estado. Esse estudo teve por objetivo conhecer as alterações morfofisiológicas de pele de camundongos após inoculação com o veneno total desta serpente. Os animais foram distribuídos em dois grupos que receberam concentrações de 40µg/mL e 20 µg/mL respectivamente, inoculados via subcutânea, além de um terceiro grupo que recebeu via intradérmica 40µg/mL do veneno. Os resultados macroscópicos apresentaram a presença de uma crosta na região inoculada, bem como a presença de hemorragia, tal atividade foi confirmada por achado histopatológico. Microscopicamente, todos os grupos experimentais apresentaram infiltrado inflamatório linfoblástico e de polimorfonucleares, hemorragia, edema, e presença de fibrose. O veneno da serpente Philodryas nattereri alterou a arquitetura normal do tegumento. Nossos resultados corroboraram em demonstrar tais alterações, uma vez que esta substância tóxica de origem animal, presente na nossa biodiversidade nordestina apresenta poucos dados na literatura, sendo desta forma, uma importante ferramenta para estudos das alterações morfofisiológicas de pele.

Snake venoms are composed of complex active substances, most of them of protein nature, causing various effects on humans and domestic animals and can lead to death. Philodryas nattereri is a native snake Ceara region, found throughout the state. This study aimed to know the morphological and physiological changes in mouse skin after inoculation with the total venom this serpente. The animals were divided into two groups that received concentrations of 40µg/mL and 20µg/mL respectively, inoculated subcutaneously, and a third group that received intradermal 40µg/mL of the venom. The macroscopic results showed the presence of a crust in the inoculated area, and the presence of bleeding, this activity was confirmed by histopathological analysis. Microscopically, all experimental groups had lymphoblastic and polymorphonuclear inflammatory infiltration, hemorrhage, edema, and fibrosis. The venom of the snake Philodryas nattereri altered the normal integument architecture. Our results corroborate to demonstrate such changes, since this toxic substance of animal origin present in our Northeast biodiversity presents few literature data, thereby being an important tool for the study of morphological and physiological changes in the skin.

Los venenos de serpientes se componen de sustancias activas complejas, la mayoría de ellos de naturaleza proteica, provocando diversos efectos sobre los seres humanos y en los animales domésticos pueden llevar a la muerte. Philodryas nattereri es una serpiente nativa de la región de Ceará, que se encuentra en todo el estado. Este estudio tuvo como objetivo conocer los cambios morfológicos y fisiológicos en la piel de ratones después de la inoculación con todo el veneno de esta serpiente. Los animales fueron divididos en dos grupos que recibieron las concentraciones de 40µg/mL y 20µg /mL, respectivamente, por vía subcutánea inoculado, y un tercer grupo recibieron intradérmica 40µg/mL veneno. Los resultados macroscópicos mostraron la presencia de una costra en el área inoculada, y la presencia de sangrado, esta actividad se confirmó por análisis histopatológica. Microscópicamente, todos los grupos experimentales tuvieron infiltración linfoblástica y polimorfonucleares inflamatoria, hemorragia, edema y fibrosis. El veneno de la serpiente Philodryas nattereri altera la arquitectura normal del tegumento. Nuestros resultados corroboran para demostrar tales cambios, ya que esta sustancia tóxica de origen animal presente en nuestra biodiversidad Northeast presenta pocos datos de la literatura, siendo por lo tanto una herramienta importante para el estudio de los cambios morfológicos y fisiológicos en la piel.

Alterações morfológicas de pele de camundongos inoculados com o veneno total da serpente Philodryas nattereri / Morphological alterations in mice skins inoculated with the total snake venom of Philodryas nattereri / Las alteraciones morfológicas en la piel de ratones causadas por el veneno de la serpiente Philodryas nattereri

Venenos de serpentes são compostos por substâncias ativas complexas, sendo a maioria delas de natureza proteica, causando diversos efeitos no ser humano e animais domésticos podendo levar ao óbito. Philodryas nattereri é uma serpente nativa da região do Ceará, sendo encontrada em todo o estado. Esse estudo teve por objetivo conhecer as alterações morfofisiológicas de pele de camundongos após inoculação com o veneno total desta serpente. Os animais foram distribuídos em dois grupos que receberam concentrações de 40µg/mL e 20 µg/mL respectivamente, inoculados via subcutânea, além de um terceiro grupo que recebeu via intradérmica 40µg/mL do veneno. Os resultados macroscópicos apresentaram a presença de uma crosta na região inoculada, bem como a presença de hemorragia, tal atividade foi confirmada por achado histopatológico. Microscopicamente, todos os grupos experimentais apresentaram infiltrado inflamatório linfoblástico e de polimorfonucleares, hemorragia, edema, e presença de fibrose. O veneno da serpente Philodryas nattereri alterou a arquitetura normal do tegumento. Nossos resultados corroboraram em demonstrar tais alterações, uma vez que esta substância tóxica de origem animal, presente na nossa biodiversidade nordestina apresenta poucos dados na literatura, sendo desta forma, uma importante ferramenta para estudos das alterações morfofisiológicas de pele.(AU)

Snake venoms are composed of complex active substances, most of them of protein nature, causing various effects on humans and domestic animals and can lead to death. Philodryas nattereri is a native snake Ceara region, found throughout the state. This study aimed to know the morphological and physiological changes in mouse skin after inoculation with the total venom this serpente. The animals were divided into two groups that received concentrations of 40µg/mL and 20µg/mL respectively, inoculated subcutaneously, and a third group that received intradermal 40µg/mL of the venom. The macroscopic results showed the presence of a crust in the inoculated area, and the presence of bleeding, this activity was confirmed by histopathological analysis. Microscopically, all experimental groups had lymphoblastic and polymorphonuclear inflammatory infiltration, hemorrhage, edema, and fibrosis. The venom of the snake Philodryas nattereri altered the normal integument architecture. Our results corroborate to demonstrate such changes, since this toxic substance of animal origin present in our Northeast biodiversity presents few literature data, thereby being an important tool for the study of morphological and physiological changes in the skin.(AU)

Los venenos de serpientes se componen de sustancias activas complejas, la mayoría de ellos de naturaleza proteica, provocando diversos efectos sobre los seres humanos y en los animales domésticos pueden llevar a la muerte. Philodryas nattereri es una serpiente nativa de la región de Ceará, que se encuentra en todo el estado. Este estudio tuvo como objetivo conocer los cambios morfológicos y fisiológicos en la piel de ratones después de la inoculación con todo el veneno de esta serpiente. Los animales fueron divididos en dos grupos que recibieron las concentraciones de 40µg/mL y 20µg /mL, respectivamente, por vía subcutánea inoculado, y un tercer grupo recibieron intradérmica 40µg/mL veneno. Los resultados macroscópicos mostraron la presencia de una costra en el área inoculada, y la presencia de sangrado, esta actividad se confirmó por análisis histopatológica. Microscópicamente, todos los grupos experimentales tuvieron infiltración linfoblástica y polimorfonucleares inflamatoria, hemorragia, edema y fibrosis. El veneno de la serpiente Philodryas nattereri altera la arquitectura normal del tegumento. Nuestros resultados corroboran para demostrar tales cambios, ya que esta sustancia tóxica de origen animal presente en nuestra biodiversidad Northeast presenta pocos datos de la literatura, siendo por lo tanto una herramienta importante para el estudio de los cambios morfológicos y fisiológicos en la piel.(AU)

Local and hematological alterations induced by Philodryas olfersii snake venom in mice.

Envenomation by the South American opisthoglyphous snake Philodryas olfersii causes local pain, edema, erythema and ecchymosis; systemic envenomation is rare. In this work, we examined the inflammatory activity of P. olfersii venom (10, 30 and 60 µg) in mouse gastrocnemius muscle 6 h after venom injection. Intramuscular injection of venom did not affect hematological parameters such as red cell count, hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration. The venom caused thrombocytopenia (at all three doses), leukopenia and lymphopenia (both at the two highest doses), as well as neutrophilia (30 µg), monocytosis (30 µg) and basophilia (10 µg). Of the cytokines that were screened [IL-1ß, IL-6, IL-10, IL-13, IL-17, TNF-α, IFN-γ, MIP-2 and KC] and IGF-1, only IGF-1 showed a significant increase in its circulating concentration, seen with 60 µg of venom; there were no significant changes in the cytokines compared to control mice. Histological analysis revealed the presence of edema, an inflammatory infiltrate and progressive myonecrosis. Edema and myonecrosis were greatest with 60 µg of venom, while the inflammatory infiltrate was greatest with 10 µg of venom. All venom doses caused the migration of polymorphonuclear and mononuclear leukocytes into muscle, but with no significant dose-dependence in the response. These findings show that, at the doses tested, P. olfersii venom does not cause hematological alterations and has limited effect on circulating cytokine concentrations. These data also confirm that the principal effects of the venom in mice are local edema, inflammatory cell infiltration and myonecrosis.

The renal effects and initial characterization of venom from Philodryas nattereri Steindachner, 1870.

The venom of the snake Philodryas nattereri is a mixture of proteins and toxic peptides with several important local and systemic actions, which are similar to those occurring in Bothrops snake bites. The mechanisms involved in the local and systemic actions of this venom are unknown. The aims of the work were to initial characterization of P. nattereri venom and investigate the effects of the poison in the renal perfusion system and in cultured renal tubular cells of the type MDCK (Madin-Darby canine kidney). The P. nattereri venom is composed majority of proteins (86.3%) and this poison promoted changes in all the evaluated renal parameters, mainly decreasing renal perfusion pressure (PP) and renal vascular resistance (RVR) and increasing urine flow (UF) and glomerular filtration rate (GFR). The most relevant result was that this venom was highly detrimental to the renal tubules independent of the PP reduction, which was shown by a decrease in sodium (Na+), potassium (K+) and chloride (Cl-) electrolyte transport in the studied concentrations. The glomeruli and tubules contain protein bodies and blood extravasation, which were observed by histological analysis. The venom of P. nattereri reduced viability of the MDCK cells only at high concentrations (50 and 100 µg/mL) with an IC50 of 169.5 µg/mL.

Bites by the colubrid snake Philodryas patagoniensis A clinicaland epidemiological study of 297 cases

We retrospectively analyzed 297 proven cases of Philodryas patagoniensis bites admitted to Hospital Vital Brazil (HVB), Butantan Institute, São Paulo, Brazil, between 1959 and 2008.Only cases in which the causative animal was brought and identified were included. Part of the snakes brought by the patients was still preserved in the collection maintained by theLaboratory of Herpetology. Of the 297 cases, in 199 it was possible to describe the gender of the snake, and seventy three (61.3%) of them were female. The length of snakes (snoutventlength) ranged from 160 to 1080 mm. In 117 snakes their state of preservationenabled the dissection and examination of their stomach contents. The stomach wasempty in 106 snakes (89.1%). Most bites occurred in the seasons of spring and summer (n » 196, 66.0%) and during warmer periods of the day. The mean age of the victims was 24.1 15.1 years old and 206 (69.4%) patients were men. Around 92% of the patientssought medical care within 6 h after the bite. Both lower (n » 188, 63.3%) and upper limbs (n » 102, 34.3%) were most frequently bitten, especially the feet and hands (n » 205, 69.0%). The local clinical manifestations were pain (n » 151, 50.8%), transitory bleeding (n » 106, 35.7%), erythema (n » 47, 15.8%) and edema (n » 39, 13.1%). Ecchymosis was not observed. Only 7 (2.4%) patients reported systemic symptoms...