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Considerable heterogeneity and ontogenetic changes in venom composition have already been observed in different species of snakes within the Viperidae family. Since the venom of young and adult can cause distinct pathological effects and because the antivenom may be less effective in neutralizing envenoming by young snakes compared to adults, it is of paramount importance to understand the ontogenetic variation of snake venom. Thus, the present study aimed to analyze and compare the venom of Bothrops pauloensis snakes, searching for possible influences of ontogeny and sex in their biochemical and biological aspects. The venom of younger individuals was more complex in relation to high molecular mass proteins, with a greater abundance of metalloproteinases, while adults showed a greater abundance of medium and low molecular mass proteins, such as phospholipases A

The venom color variation of Crotalus durissus terrificus (Cdt) is attributed to the presence of the toxin L-amino acid oxidase (LAAO). During the venom milking routine of Instituto Butantan, we have noticed that most venoms of captive Cdt specimens show a yellowish color, while most venoms of wild specimens are white. Here we describe a comparative analysis of long-term captive (LTC) and recently wild-caught (RWC) Cdt, focusing on LAAO variation. For the identification of LAAO in individual venoms, four different approaches were employed: evaluation of the enzymatic activity, SDS-PAGE, Western blotting, and ELISA. In addition, mass spectrometry analysis was performed using pooled samples. Although some variation among these methodologies was observed, it was possible to notice that the presence of LAAO was significantly higher in the venom of LTC individuals. LAAO was identified in 60–80% LTC specimens and in only 10–12% of RWC specimens. Furthermore, this enzyme accounts for 5.6% of total venom proteins of LTC Cdt pooled venom, while it corresponds to only 0.7% of RWC Cdt pooled venom. These findings strongly suggest that captive maintenance increases the expression of LAAO in Cdt venom.

10 págs, 5 figuras. Información suplementaria en: https://doi.org/10.1016/j.toxicon.2020.07.001, The South American rattlesnake Crotalus durissus spp has a wide geographic distribution in Brazil. Although responsible for only a low proportion of ophidian accidents, it is considered one of the most medically important species of venomous snakes due to the high mortality rate (1.87%). Snake venom is a complex phenotype commonly subjected to individual intraspecific, ontogenetic and geographic variability. Compositional differences in pooled venom used in the immunization process may impact the efficacy of the antivenom. In order to assure standardized high-quality antivenom, the potency of each Brazilian crotalic antivenom batch is determined against the 'Brazilian Crotalic Reference Venom' (BCRV). BCRV is produced by Instituto Butantan using venom obtained from the first milking of recently wild-caught C. d. terrificus specimens brought to the Institute. The decrease in the number of snake donations experienced in recent years can become a threat to the production of future batches of BCRV. To evaluate the feasibility of using venom from long-term captive animals in the formulation of BCRV, we have compared the proteomic, biochemical and biological profiles of C. d. terrificus venom pooled from captive specimens (CVP- captive venom pool) and BCRV. Electrophoretic and venomics analyses revealed a very similar venom composition profile, but also certain differences in toxins abundance, with some low abundant protein families found only in BCRV. Enzymatic (L-amino acid oxidase, phospholipase A2 and proteolytic) and biological (myotoxic and coagulant) activities showed higher values in CVP than in BCRV. CVP also possessed slightly higher lethal effect, although the Instituto Butantan crotalic antivenom showed equivalent potency neutralizing BCRV and CVP. Our results strongly suggest that venom from long-term captive C. d. terrificus might be a valid alternative to generate an immunization mixture of equivalent quality to the currently in use reference venom., This work was financially supported by Fundaç~ao de Amparo �a Pesquisa do Estado de S~ao Paulo – FAPESP (grant numbers: 2017/ 01890–0, 2018/25786–0; 2018/25899–0, 2017/26533–6 and 2017/ 16908–2), Conselho Nacional de Desenvolvimento Científico e Tec-nol�ogico (CNPq) (405399/2018–9) and partly funded by grant BFU2017-89103-P (Ministerio de Ciencia, Innovación y Universidades, Madrid, Spain).

We report a structural and functional proteomics characterization of the venoms of the two subspecies (bilineatus and smaragdinus) of the South American palm pitviper B. bilineatus from the Brazili...

This work compared the presence of phospholipase A

The Brazilian lancehead (Bothrops moojeni) has a wide distribution in Brazil and represents a serious public health hazard. Previous works reported that the symptoms of snakebites caused by B. moojeni juveniles’ bites were mainly related to coagulation, while those caused by adults’ bites had a more prominent local damage. In this work, we analyzed the venoms of B. moojeni at different life stages to better understand the ontogeny shift in this species. Snakes were grouped by age and sex, and venom pools were formed accordingly. Compositional analyses by one-dimensional electrophoresis (1-DE), chromatography, and mass spectrometry revealed that ontogenetic changes might be mostly related to phospholipase A2 (PLA2) and metalloproteases. Regarding the venoms functional aspect, proteolytic, L-amino acid oxidase, PLA2, and coagulant in vitro activities were assayed, but only the first and the last ones showed age-related changes, with the venom of snakes up to 1 year-old displaying lower proteolytic and higher coagulant activities, while those from 2 years-old onward presented the opposite relation. The venoms of 3 years-old snakes were exceptions to the compositional and functional pattern of adults as both venoms presented profiles similar to neonates. Sex-related differences were observed in specific groups and were not age-related. In vivo experiments (median lethal dose and hemorrhagic activity) were statistically similar between neonates and adults, however we verified that the adult venom killed mice faster comparing to the neonates. All venoms were mostly recognized by the antibothropic serum and displayed similar profiles to 1-DE in western blotting. In conclusion, the Brazilian lancehead venom showed ontogenetic shift in its composition and activities. Furthermore, this change occurred in snakes from 1 to 2 years-old, and interestingly the venom pools from 3 years-old snakes had particular characteristics, which highlights the importance of comprehensive studies to better understand venom variability.

The number of snakes donated to the Brazilian Instituto Butantan has been decreasing in the past 10 years. This circumstance motivated us to compare the properties of five venom pools of Bothrops jararaca snake stored for up to 54 years. Results showed differences among venom pools regarding enzymatic and other biological activities, such as caseinolytic, phospholipase A2, hemorrhagic and coagulant activities, as well as antigenicity. Protein content, reverse-phase chromatographic profile, and immunorecognition by commercial Bothrops antivenom were comparable for all venom pools, although lethality of the most recent preparations was higher. Since the lowest functional activities did not always correspond to older venoms, differences among venom pools used for antivenom production during the period 1963–2008 may correlate with the different proportions of venoms from different localities used in their generation, rather than to long-term storage. We conclude that B. jararaca venoms properly stored for long periods of time retain their structural and pharmacological activities, thus representing useful materials for scientific research and antivenom production.

Background: Crotalus durissus is considered one of the most important species of venomous snakes in Brazil, due to the high mortality of its snakebites. The venom of Crotalus durissus contains four main toxins: crotoxin, convulxin, gyroxin and crotamine. Venoms can vary in their crotamine content, being crotamine-negative or -positive. This heterogeneity is of great importance for producing antivenom, due to their different mechanisms of action. The possibility that antivenom produced by Butantan Institute might have a different immunorecognition capacity between crotamine-negative and crotamine-positive C. durissus venoms instigated us to investigate the differences between these two venom groups. Methods: The presence of crotamine was analyzed by SDS-PAGE, western blotting and ELISA, whereas comparison between the two types of venoms was carried out through HPLC, mass spectrometry analysis as well as assessment of antivenom lethality and efficacy. Results: The results showed a variation in the presence of crotamine among the subspecies and the geographic origin of snakes from nature, but not in captive snakes. Regarding differences between crotamine-positive and -negative venoms, some exclusive proteins are found in each pool and the crotamine-negative pool presented more phospholipase A2 than crotamine-positive pool. This variation could affect the time to death, but the lethal and effective dose were not affected. Conclusion: These differences between venom pools indicate the importance of using both, crotamine-positive and crotamine-negative venoms, to produce the antivenom.

Background: Variability in snake venoms is a well-studied phenomenon. However, sex-based variation of Bothrops atrox snake venom using siblings is poorly investigated. Bothrops atrox is responsible for the majority of snakebite accidents in the Brazilian Amazon region. Differences in the venom composition of Bothrops genus have been linked to several factors such as ontogeny, geographical distribution, prey preferences and sex. Thus, in the current study, venom samples of Bothrops atrox male and female siblings were analyzed in order to compare their biochemical and biological characteristics. Methods: Venoms were collected from five females and four males born from a snake captured from the wild in São Bento (Maranhão, Brazil), and kept in the Laboratory of Herpetology of Butantan Intitute. The venoms were analyzed individually and as a pool of each gender. The assays consisted in protein quantification, 1-DE, mass spectrometry, proteolytic, phospholipase A2, L-amino acid oxidase activities, minimum coagulant dose upon plasma, minimum hemorrhagic dose and lethal dose 50%. Results: Electrophoretic profiles of male’s and female’s venom pools were quite similar, with minor sex-based variation. Male venom showed higher LAAO, PLA2 and hemorrhagic activities, while female venom showed higher coagulant activity. On the other hand, the proteolytic activities did not show statistical differences between pools, although some individual variations were observed. Meanwhile, proteomic profile revealed 112 different protein compounds; of which 105 were common proteins of female’s and male’s venom pools and seven were unique to females. Despite individual variations, lethality of both pools showed similar values. Conclusion: Although differences between female and male venoms were observed, our results show that individual variations are significant even between siblings, highlighting that biological activities of venoms and its composition are influenced by other factors beyond gender.

O estudo dos venenos de serpentes é uma importante área da pesquisa biomédica em virtude de suas ações neurotóxicas, hemorrágicas e proteolíticas. O gênero Bothrops é considerado um dos mais importantes no Brasil pela alta incidência de acidentes ofídicos. São descritas três atividades fisiopatológicas do veneno botrópico: proteolítica, coagulante e hemorrágica. O veneno de serpentes está sujeito às variações intraespecíficas, que, por sua vez, sofrem influência de distribuição geográfica, sexo, idade (ontogenia), cativeiro, etc. Existem descrições sobre a ontogenia de alguns venenos de serpentes, porém, estudos comparativos referentes às atividades bioquímicas e biológicas de espécimes adultos e jovens de algumas espécies, como a B. moojeni, não foram completamente elucidados. Com isso, o presente estudo teve como objetivo caracterizar e comparar, bioquímica e biologicamente, a influência da ontogenia e do sexo no veneno da serpente B. moojeni. Comparando esses parâmetros, os venenos apresentaram diferenças bastante evidentes quanto à composição, e, principalmente, quanto às atividades proteolítica e coagulante. Os venenos de serpentes mais jovens são mais coagulantes, enquanto os de adultos são mais proteolíticos; já em relação ao sexo, os venenos de fêmeas se mostraram mais proteolíticos do que os de machos, que, em contrapartida, são mais coagulantes. Apesar deste contraste, a letalidade dos venenos de neonatos e de adultos não apresentou diferença estatística, mas o veneno de adultos apresentou ação mais rápida sobre os animais. Além disso, o imunorreconhecimento pelo soro antibotrópico foi bastante similar entre os venenos analisados. Estes resultados sugerem que, apesar das variações observadas, a letalidade não se altera, talvez devido ao sinergismo das proteínas, e o bom imunorreconhecimento pode indicar uma boa resposta do soro antibotrópico no tratamento dos acidentes ofidicos causados pela B. moojeni. The study of snake venoms is an important area of biomedical research for its neurotoxic, hemorrhagic and proteolytic effects. Bothrops is one of the most important genera in Brazil due to the high incidence of snake bites. Three physiopathological activities are described for the bothropic venom: proteolytic, procoagulant and hemorrhagic. Snake venom is susceptible to intraspecific variations that are related to geographic distribution, sex, age (ontogeny), captivity, etc. Although described for many species, studies regarding comparison of the biochemical and biological features between adult and juvenile snake venoms are not completely elucidated for some species, like B. moojeni. Thereby, the present study aimed to characterize and compare, biochemically and biologically, the influence of ontogeny and sex on the snake venom of B. moojeni. Analyzing these parameters, some differences were quite marking in the venom composition and, especially, concerning proteolytic and procoagulant activities. The venom of younger snakes are showed higher coagulant activity, while adults were more proteolytic; in relation to sex, female venoms were more proteolytic than male, which were more coagulant instead. Despite these differences, the lethality did not show statistical difference, although adult venom acted faster than neonate venom. Besides, immunorecognition of the venom by antibothropic serum was very similar among the venoms. These results suggest that lethality of the venom does not vary according to age, so it might be related to the sinergism of the proteins in it, and the immunorecognition can indicate a possible good response to the treatment with antibothropic serum of snake bites caused by B. moojeni.