Avaliação anti-inflamatória e antipeçonhenta das espécies Hancornia speciosa e Mimosa tenuiflora em modelos experimentais de inflamação e envenenamento induzidos por Bothrops jararaca e Tityus serrulatus

Accidents caused by venomous animals represents a significant and serious public health problem in certain regions of Brazil, as well as in other parts of the world by the frequency with which they occur and the mortality they cause. The use of plant extracts as an antidote for poisoning cases is an ancient practice used in many communities that have no access to antivenom. Medicinal plants represent an important source of obtaining bioactive compounds able to assist directly in the treatment of poisoning or indirectly supplementing serum therapy currently used. The aim of this study was to evaluate the effect of extracts, fractions and isolated compounds from M. tenuiflora and H. speciosa in the inflammatory process induced by carrageenan and the venom of B. jararaca and T. serrulatus. The results showed that both M. tenuiflora and H. speciosa were capable of inhibiting cell migration and cytokines levels in peritonitis induced by carrageenin and venom of T. serrulatus. In poisoning by B. jararaca model, mice treated with the plants in studies decreased the leukocyte influx into the peritoneal cavity. Finally the M. tenuiflora and H. speciosa had antiphlogistic activity, reducing edema formation and exerted inhibitory action of leukocyte migration in local inflammation induced by the venom of B. jararaca. Through of Thin Layer Chromatography (TLC) analysis was possible identified the presence of flavonoids ,saponins and/or terpenes in aqueous extract of M. tenuiflora. By High Performance Liquid Chromatography analysis, it was possible to identify the presence of rutin and chlorogenic acid in aqueous extract of H. speciosa. We conclude that the administration of extracts, fractions and isolated compounds of H. speciosa and M. tenuiflora resulted in inhibition of the inflammatory process in different experimental models. This study demonstrates for the first time the effect of M. tenuiflora and H. speciosa in inhibition of the inflammation caused by B. jararaca and T. serrulatus venom.

Nanopartículas catiônicas de poli (ácido lático) para liberação modificada de peptídios da peçonha do escorpião Tityus serrulatus

Reported accidents involving the poisoning scorpions are still frequent in Brazil, mainly caused by Tityus serrulatus, known as yellow scorpion. Although antivenom sera are produced routinely by various government laboratories, the effectiveness of its use depends on how quickly treatment is initiated and efficiency in the production of antibodies by the immunized animals. In this study, the development of cationic polymeric nanoparticles of poly(lactic acid) aimed to create a modified delivery system for peptides and proteins of T. serrulatus venom, able to enhance the production of serum antibodies against the scorpion toxins. The cationic nanoparticles were obtained by a low energy nanoprecipitation, after study of the parameters’ variations effects over the physicochemical properties of the particles. The surface functionalization of the nanoparticles with the hyperbranched polyethyleneimine was proved by zeta potential analysis and enabled the adsorption by electrostatic interaction of different types of proteins. The protein loading efficiency of 40-80 % to bovine serum albumin (BSA) and 100 % to scorpion venom peptides evaluated by spectrophotometry and polyacrylamide gel electrophoresis confirmed the success of the selected parameters established for obtainment of nanoparticles, produced with size between 100 to 250 nm. The atomic force microscopy analysis and in vitro release showed that the spherical nanoparticles provided a sustained release profile of proteins by diffusion mechanism, demonstrating the potential for application of the nanoparticles in vivo.

Nanopartículas catiônicas de poli (ácido lático) para liberação modificada de peptídios da peçonha do escorpião Tityus serrulatus

Reported accidents involving the poisoning scorpions are still frequent in Brazil, mainly caused by Tityus serrulatus, known as yellow scorpion. Although antivenom sera are produced routinely by various government laboratories, the effectiveness of its use depends on how quickly treatment is initiated and efficiency in the production of antibodies by the immunized animals. In this study, the development of cationic polymeric nanoparticles of poly(lactic acid) aimed to create a modified delivery system for peptides and proteins of T. serrulatus venom, able to enhance the production of serum antibodies against the scorpion toxins. The cationic nanoparticles were obtained by a low energy nanoprecipitation, after study of the parameters’ variations effects over the physicochemical properties of the particles. The surface functionalization of the nanoparticles with the hyperbranched polyethyleneimine was proved by zeta potential analysis and enabled the adsorption by electrostatic interaction of different types of proteins. The protein loading efficiency of 40-80 % to bovine serum albumin (BSA) and 100 % to scorpion venom peptides evaluated by spectrophotometry and polyacrylamide gel electrophoresis confirmed the success of the selected parameters established for obtainment of nanoparticles, produced with size between 100 to 250 nm. The atomic force microscopy analysis and in vitro release showed that the spherical nanoparticles provided a sustained release profile of proteins by diffusion mechanism, demonstrating the potential for application of the nanoparticles in vivo.

Renal effects and vascular reactivity induced by Tityus serrulatus venom

Tityus serrulatus, popularly known as yellow scorpion, is one of the most studied scorpion species in South America and its venom has supplied some highly active molecules. The effects of T. serrulatus venom upon the renal physiology in human showed increased renal parameters, urea and creatinine. However, in perfused rat kidney the effects were not tested until now. Isolated kidneys from Wistar rats, weighing 240-280 g, were perfused with Krebs-Henseleit solution containing 6% (g weight) of previously dialysed bovine serum albumin. The effects of T. serrulatus venom were studied on the perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF), glomerular filtration rate (GFR), sodium tubular transport (%TNa+), potassium tubular transport (%TK+) and chloride tubular transport (%TCl-). Tityus serrulatus venom (TsV; 10 mu g/mL) was added to the system 30 min after the beginning of each experiment (n = 6). This 30 min period was used as an internal control. The mesenteric bed was perfused with Krebs solution kept warm at 37 T by a constant flow (4 mL/min), while the variable perfusion pressure was measured by means of a pressure transducer. The direct vascular effects of TsV (10 mu g/mL/min; n=6), infused at a constant rate (0.1 mL/min), were examined and compared to the infusion of the vehicle alone at the same rate. TsV increased PP (PP30'= 127.8 +/- 0.69 vs PP60' = 154.2 +/- 14 mmHg*, *p < 0.05) and RVR (RVR30' = 6.29 +/- 0.25 vs RVR60' = 8.03 +/- 0.82 mmHg/mL g(-1) min(-1)*, *p < 0.05), decreased GFR (GFR(30') =0.58 +/- 0.02 vs GFR(60') = 0.46 +/- 0.01 mL g(-1) min(-1)*, *p < 0.05) and UF (UF30' = 0.135 +/- 0.001 vs UF60' = 0.114 +/- 0.003 mL g(-1)min(-1)*, *p < 0.05). Tubular transport was not affected during the whole experimental period (120 min). on the other hand, the infusion of TsV (10 mu g/mL/min) increased the basal perfusion pressure of isolated arteriolar mesenteric bed (basal pressure: 74.17 +/- 3.42 vs TsV 151.8 +/- 17.82 mmHg*, *p < 0.05). TsV affects renal haemodynamics probably by a direct vasoconstrictor action leading to decreased renal flow. (c) 2005 Elsevier Ltd. All rights reserved.

Effects of Tityus serrulatus scorpion venom on lung mechanics and inflammation in mice

The present study evaluated the effects of an intramuscular injection of Tityus serrulatus venom (TsV) (0.67 mu g/g) on lung mechanics and lung inflammation at 15, 30, 60 and 180 min after inoculation. TsV inoculation resulted in increased lung elastance when compared with the control group (p < 0.001): these values were significantly higher at 60 min than at 15 and 180 min (p < 0.05). Resistive pressure (Delta P(1)) values decreased significantly at 30, 60 and 180 min after TsV injection (p < 0.001). TsV inoculation resulted in increased lung inflammation, characterised by an increased density of mononuclear cells at 15, 30, 60 and 180 min after TsV injection when compared with the control group (p < 0.001). TsV inoculation also resulted in an increased pulmonary density of polymorphonuclear cells at 15, 30 and 60 min following injection when compared to the control group (p < 0.001). In conclusion, T serrulatus venom leads to acute lung injury, characterised by altered lung mechanics and increased pulmonary inflammation. (C) 2009 Elsevier Ltd. All rights reserved.

Envenomation by scorpion in dog: case report

A case admitted at the Small Animals Clinics Service, Veterinary Hospital, FMVZ - UNESP, in May, 1999 is described. A Brazilian Terrier dog, 3 years and 3 months old, weighing 1.7 kg was brought after 2 hours and a half from contact with a scorpion (Tityus bahiensis). The dog showed vocalization inserted with drowsiness. Physical examination showed slightly hyperemic mucous, pain, agressiveness, tachypnea, tachycardia, and discrete erythema on the right forelimb palmar face. An anesthetic block was performed around the stung area using 2% lidocaine hydrochloride without vasoconstrictor (10mL). The animal was asymptomatic, after 24 h treatment.

Clinical and cardiovascular alterations produced by scorpion envenomation in dogs

Scorpionism is a common problem that occurs in tropical and subtropical countries and assumes great medical-sanitary importance due to its fatal effect on sensitive individuals, being able to lead children and aged people to death. The envenomation lethal potential is responsible for the serious cardiopulmonary alterations the scorpion toxin produces in its victims. The present research evaluated the effects of Tityus serrulatus venom on dogs, using two distinct doses: a dose that simulates natural envenomation (0.4 mg/total dose), and an experimental dose (0.25 mg/kg). General clinical signs were observed at different moments after envenomation, and specific data related to the cardiopulmonary system were evaluated by systemic arterial pressure measurement, CK-MB enzymatic activity dosage, and radiographic, electrocardiographic and echocardiographic examinations. Results demonstrated that the scorpion venom, in experimental doses, was able to cause acute and reversible cardiac injury in few days, and, in the dose that simulated natural accident, it produced clinical signs of light envenomation, such as local pain, hyperesthesia, sialorrhea, vomiting, diarrhea, sneeze and prostration.

High chromosome variability and the presence of multivalent associations in buthid scorpions

In this study, we investigated the mitotic and meiotic chromosomes of 11 Buthidae scorpion species, belonging to three genera (Ananteris, Rhopalurus and Tityus), to obtain detailed knowledge regarding the mechanisms underlying the intraspecific and/or interspecific diversity of chromosome number and the origin of the complex chromosome associations observed during meiosis. The chromosomes of all species did not exhibit a localised centromere region and presented synaptic and achiasmatic behaviour during meiosis I. Spermatogonial and/or oogonial metaphase cells of these buthids showed diploid numbers range from 2n = 6 to 2n = 28. In most species, multivalent chromosome associations were observed in pachytene and postpachytene nuclei. Moreover, intraspecific variability associated with the presence or absence of chromosome chains and the number of chromosomes in the complex meiotic configurations was observed in some species of these three genera. Silver-impregnated cells revealed that the number and location of nucleolar organiser regions (NORs) remained unchanged despite extensive chromosome variation; notably, two NORs located on the terminal or subterminal chromosome regions were commonly observed for all species. C-banded and fluorochrome-stained cells showed that species with conspicuous blocks of heterochromatin exhibited the lowest rate of chromosomal rearrangement. Based on the investigation of mitotic and meiotic cells, we determined that the intraspecific variability occurred as a consequence of fission/fusion-type chromosomal rearrangements in Ananteris and Tityus species and reciprocal translocation in Rhopalurus species. Furthermore, we verified that individuals presenting the same diploid number differ in structural chromosome organisation, giving rise to intraspecific differences of chromosome association in meiotic cells (bivalent-like elements or chromosome chains). © 2013 Springer Science+Business Media Dordrecht.

Alterações clínicas e cardiopulmonares produzidas pelo envenenamento escorpiônico em cães

Pós-graduação em Medicina Veterinária - FMVZ

Aspectos epidemiológicos e clínicos do escorpionismo na região de Santarém, Estado do Pará, Brasil

Este trabalho é um estudo prospectivo e descritivo dos aspectos epidemiológicos e clínicos de 72 envenenamentos por escorpiões admitidos no Hospital Municipal de Santarém, Estado do Pará, Brasil, entre fevereiro de 2000 a fevereiro de 2001. Trouxeram o animal 8,3% das vítimas, os quais foram identificados como T. cambridgei. O sexo masculino foi acometido em 83,3%. A idade das vítimas e o tempo para o socorro médico foram respectivamente de 33,6±18,3 anos e 4,6±3,2 horas em média. Os membros superiores foram acometidos em 51,5% dos casos. As manifestações locais estiveram presentes em 91,7% e as sistêmicas em 98,6% dos envenenamentos. Entre os sintomas locais encontramos: parestesia em 79,2%, dor em 52,8%, e edema em 26,4% dos casos. Nas manifestações sistêmicas predominou as queixas neurológicas em 97,2% das vítimas, sendo o sintoma de sensação de "choque elétrico" pelo corpo (88,9%) o mais freqüente. No exame neurológico os sinais mais encontrados foram: mioclonias (93,0%), dismetria (86,1%), disartria (80,6%) e ataxia de marcha (70,8%). Classificou-se como moderados 76,4% dos envenenamentos, sem nenhum caso grave. Deixaram de realizar a soroterapia 32,7% dos casos moderados, por ausência de soro específico no momento do atendimento. O escorpionismo da região de Santarém mostra um comportamento clínico regional diferente daqueles descritos no Brasil e de outros locais da Amazônia e, apresenta uma clínica predominantemente neurológica, ainda não descrita na literatura brasileira.

Location of 45S Ribosomal Genes in Mitotic and Meiotic Chromosomes of Buthid Scorpions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Organization and behavior of the synaptonemal complex during achiasmatic meiosis of four buthid scorpions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

General biochemical and immunological characteristics of the venom from Peruvian scorpion Hadruroides lunatus

This communication describes the general biochemical properties and some immunological characteristics of the venom from the Peruvian scorpion Hadruroides lunatus, which is the most medically relevant species in Peru. The soluble venom of this scorpion is toxic to mice, the LD50 determined was 0.1 mg/kg and 21.55 mg/kg when the venom was injected intracranial or intraperitoneally, respectively. The soluble venom displayed proteolytic, hyaluronidasic, phospholipasic and cardiotoxic activities. High performance liquid chromatography of the soluble venom resulted in the separation of 20 fractions. Two peptides with phospholipasic activity were isolated to homogeneity and their molecular masses determined by mass spectrometry (MALDI TOF). Anti-H. lunatus venom sera were produced in rabbits. Western blotting analysis showed that most of the protein content of this venom is immunogenic. H. lunatus anti-venom displayed consistent cross-reactivity with venom antigens from the new World-scorpions Tityus serrulatus and Centruroides sculpturatus venoms; however, a weaker reactivity was observed against the venom antigens from the old World-scorpion Androctonus australis Hector. (C) 2012 Elsevier Ltd. All rights reserved.

Looking over Toxin-K+ Channel Interactions. Clues from the Structural and Functional Characterization of alpha-KTx Toxin Tc32, a Kv1.3 Channel Blocker

alpha-KTx toxin Tc32, from the Amazonian scorpion Tityus cambridgei, lacks the dyad motif; including Lys27, characteristic of the family and generally associated with channel blockage. The toxin has been cloned and expressed for the first time. Electrophysiological experiments, by showing that the recombinant form blocks Kv1.3 channels of olfactory bulb periglomerular cells like the natural Tc32 toxin, when tested on the Kv1.3 channel of human T lymphocytes, confirmed it is in an active fold. The nuclear magnetic resonance-derived structure revealed it exhibits an alpha/beta scaffold typical of the members of the alpha-KTx family. TdK2 and TdK3, all belonging to the same alpha-KTx 18 subfamily, share significant sequence identity with Tc32 but diverse selectivity and affinity for Kv1.3 and Kv1.1 channels. To gain insight into the structural features that may justify those differences, we used the recombinant Tc32 nuclear magnetic resonance-derived structure to model the other two toxins, for which no experimental structure is available. Their interaction with Kv1.3 and Kv1.1 has been investigated by means of docking simulations. The results suggest that differences in the electrostatic features of the toxins and channels, in their contact surfaces, and in their total dipole moment orientations govern the affinity and selectivity of toxins. In addition, we found that, regardless of whether the dyad motif is present, it is always a Lys side chain that physically blocks the channels, irrespective of its position in the toxin sequence.

Accurate prediction of scorpion toxin functional properties from primary structures

Scorpion toxins are common experimental tools for studies of biochemical and pharmacological properties of ion channels. The number of functionally annotated scorpion toxins is steadily growing, but the number of identified toxin sequences is increasing at much faster pace. With an estimated 100,000 different variants, bioinformatic analysis of scorpion toxins is becoming a necessary tool for their systematic functional analysis. Here, we report a bioinformatics-driven system involving scorpion toxin structural classification, functional annotation, database technology, sequence comparison, nearest neighbour analysis, and decision rules which produces highly accurate predictions of scorpion toxin functional properties. (c) 2005 Elsevier Inc. All rights reserved.