A "hotspot" within a hotspot: the reptiles of the Estação Ecológica and Área de Proteção Ambiental de Murici, Atlantic Forest of northeastern Brazil / Um "hotspot" dentro de um hotspot: os répteis da Estação Ecológica e Área de Proteção Ambiental de Murici, Mata Atlântica do nordeste do Brasil

Abstract: Currently the Atlantic Forest hotspot has less than 11% of its original coverage. However approximately 300 species of reptiles are known to inhabit this ecoregion, of which 34% are endemic. The creation of protected areas represents a strategy for preserving ecosystems and managing land use, and for attaining the proper management of these protected areas, information on local biodiversity is essential. Herein we provide the first list of reptile species for the Estação Ecológica and Área de Proteção Ambiental de Murici, two overlapping protected areas located in the state of Alagoas, one of the most important sets of forest remnants for the conservation of the Atlantic Forest in the northeast of Brazil. The species list was constructed based on expeditions and occasional encounters in the area between 1994 and 2022. A total of 89 reptile species were obtained during the 28 years of collection, being two species of Crocodylia, three species of Testudines and 84 species of Squamata. This richness is by far one of the greatest ever documented for the Atlantic Forest. Additionally, two species registered in the area are considered threatened according to the national list (Amerotyphlops paucisquamus and Bothrops muriciensis) and six are defined as data deficient for the assessment of their conservation status. Three species are recorded for the first time in the Atlantic Forest north of the São Francisco River: Dipsas indica, Trilepida salgueiroi and Cercophis auratus. We claim that the species list provided here will serve as a starting point for further studies in this rich reptile "hotspot" within the Atlantic Forest.

Resumo: Atualmente o hotspot da Mata Atlântica tem menos de 11% de sua cobertura original. Porém aproximadamente 300 espécies de répteis são conhecidas por habitar esta ecorregião, das quais 34% são endêmicas. A criação de unidades de conservação representa uma estratégia de preservação de ecossistemas e gestão do uso do solo, e para o manejo adequado dessas áreas protegidas é fundamental a informação sobre a biodiversidade local. Apresentamos aqui a primeira lista de espécies de répteis para a Estação Ecológica e Área de Proteção Ambiental de Murici, duas unidades de conservação parcialmente sobrepostas localizadas no estado de Alagoas, um dos conjuntos de remanescentes florestais mais importantes para a conservação da Mata Atlântica no nordeste do Brasil. A lista de espécies foi construída com base em expedições e encontros ocasionais na área entre 1994 e 2022. Um total de 89 espécies de répteis foram registradas durante os 28 anos de coleta, sendo duas espécies de Crocodylia, três espécies de Testudines e 84 espécies de Squamata. Essa riqueza é de longe uma das maiores já documentadas para a Mata Atlântica. Além disso, duas espécies registradas na área são consideradas ameaçadas segundo a lista nacional (Amerotyphlops paucisquamus e Bothrops muriciensis) e seis são definidas como dados insuficientes para a avaliação de seu status de conservação. Três espécies são registradas pela primeira vez na Mata Atlântica ao norte do rio São Francisco: Dipsas indica, Trilepida salgueiroi e Cercophis auratus. Afirmamos que a lista de espécies aqui fornecida servirá como ponto de partida para novos estudos neste rico "hotspot" de répteis dentro da Mata Atlântica.

Helminth parasites of Mabuya arajara Rebouças-Spieker, 1981 (Lacertilia: Mabuyidae) from Chapada do Araripe, northeastern Brazil.

We provide data on the helminth fauna from the digestive tract of the lizard Mabuya arajara Rebouças-Spieker, 1981 from Chapada do Araripe, northeastern Brazil. Seventy one of the 127 lizards examined (56%) were infected with four nematode species: Physalopteroides venancioi and Physaloptera sp. (Physalopteridae), Strongyluris oscari (Heterakidae), and Parapharyngodon alvarengai (Pharyngodonidae), the latter being the component species (prevalence 53.5%; mean intensity of infection 3.37 ± 2.0; discrepancy index D = 0.69). The helminth P. alvarengai infected M. arajara throughout the year and showed increased infection rates in July, at the beginning of the dry season. In addition to the relationship with seasonality, lizards with greater body length and/or body mass were more infected. Relationships between number of parasites and body mass and with the sexes of lizards, on the other hand, were not found. Mabuya arajara represents a new host for these nematodes. This study contributes to the knowledge of the helminth fauna associated with the digestive tract of lizards from South America and the Caatinga domain.

Zoanthid mucus as new source of useful biologically active proteins.

Palythoa caribaeorum is a very common colonial zoanthid in the coastal reefs of Brazil. It is known for its massive production of mucus, which is traditionally used in folk medicine by fishermen in northeastern Brazil. This study identified biologically active compounds in P. caribaerum mucus. Crude mucus was collected during low tides by the manual scraping of colonies; samples were maintained in an ice bath, homogenized, and centrifuged at 16,000 g for 1 h at 4 °C; the supernatant (mucus) was kept at -80 °C until use. The enzymatic (proteolytic and phospholipase A2), inhibitory (metallo, cysteine and serine proteases), and hemagglutinating (human erythrocyte) activities were determined. The results showed high levels of cysteine and metallo proteases, intermediate levels of phosholipase A2, low levels of trypsin, and no elastase and chymotrypsin like activities. The mucus showed potent inhibitory activity on snake venom metalloproteases and cysteine proteinase papain. In addition, it showed agglutinating activity towards O+, B+, and A+ erythrocyte types. The hemostatic results showed that the mucus prolongs the aPTT and PT, and strongly inhibited platelet aggregation induced by arachidonic acid, collagen, epinephrine, ADP, and thrombin. The antimicrobial activity was tested on 15 strains of bacteria and fungi through the radial diffusion assay in agar, and no activity was observed. Compounds in P. caribaeorum mucus were analyzed for the first time in this study, and our results show potential pharmacological activities in these compounds, which are relevant for use in physiopathological investigations. However, the demonstration of these activities indicates caution in the use of crude mucus in folk medicine. Furthermore, the present or absent activities identified in this mucus suggest that the studied P. caribaeorum colonies were in thermal stress conditions at the time of sample collection; these conditions may precede the bleaching process in zoanthids. Hence, the use of mucus as an indicator of this process should be evaluated in the future.

Purification of a lectin with antibacterial activity from Bothrops leucurus snake venom.

A novel lectin was isolated from Bothrops leucurus snake venom using a combination of affinity and gel filtration chromatographies. The lectin (BlL) agglutinated glutaraldehyde-treated rabbit and human erythrocytes with preference for rabbit erythrocytes. Galactose, raffinose, lactose, fetal bovine serum and casein inhibited lectin-induced rabbit erythrocyte agglutination. BlL, with a molecular mass of 30 kDa and composed of two subunits of 15 kDa, showed dependence on calcium. BlL is an acidic protein with highest activity over the pH range of 4.0-7.0 and stable under heating to 70°C. Fluorescence emission spectra showed tryptophan residues partially buried within the lectin structure. The percentages of secondary structure revealed by circular dichroism were 1% α-helix, 44% ß-sheet, 24% ß-turn and 31% unordered. BlL showed effective antibacterial activity against Gram-positive bacteria Staphylococcus aureus, Enterococcus faecalis and Bacillus subtilis with minimal inhibitory concentrations of 31.25, 62.25 and 125 µg/mL, respectively. In conclusion, B. leucurus snake venom contains a galactoside-binding lectin with antibacterial activity.

BE-I-PLA2, a novel acidic phospholipase A2 from Bothrops erythromelas venom: isolation, cloning and characterization as potent anti-platelet and inductor of prostaglandin I2 release by endothelial cells.

A novel acidic Asp49 phospholipase A(2) was isolated from Bothrops erythromelas (jararaca malha-de-cascavel) snake venom by four chromatographic steps. BE-I-PLA2 present a molecular weight of 13,649.57 Da as estimated by mass spectrometry. N-terminal and four internal peptides were sequenced, covering around one-third of the complete toxin sequence. The complete BE-I-PLA2 cDNA was cloned from a B. erythromelas venom-gland cDNA library. The cDNA sequence possesses 457 bp and encodes a protein with significant sequence similarity to many other phospholipase A(2) from snake venoms. When tested in platelet rich plasma, the enzyme showed a potent inhibitory effect on aggregation induced by arachidonic acid and collagen, but not ADP. On the other hand, BE-I-PLA2 did not modify aggregation in washed platelet. Furthermore, no action of BE-I-PLA2 on the principal platelets receptors was observed. Chemical modification with p-bromophenacyl bromide abolished the enzymatic activity of BE-I-PLA2, but its anti-platelet activity was only partially inhibited. In human umbilical-cord veins endothelial cells, BE-I-PLA2 was neither apoptotic nor proliferative but stimulated endothelial cells to release prostaglandin I(2), suggesting an increase of its potential anti-platelet activity in vivo. Further studies are required in order to determine the exact mechanism of action of BE-I-PLA2 in the inhibition of platelet aggregation.

Inibição dos efeitos da Peçonha de Bothrops Erythromelas (Jararaca-Malha-de-Cascavel) pelo extrato de Jatropha Molissima (POHL) Baill / Inhibition of Bothrops Erythromelas Venom effects by Jatropha Molissima (POHL) Baill extract

Objetivo: Comprovar a atividade inibitória do extrato hidroalcoólico do caule de Jatropha Molissima (EHA) sobre os efeitos mais relevantes da peçonha de Bothrops erythromelas (PBe). Material e Métodos: A peçonha liofilizada foi obtida da Fundação Ezequiel Dias (FUNED), Minas Gerais, Brasil. O extrato hidroalcoólico foi obtido do Laboratório de Produtos Naturais (UFPE), Recife, Pernambuco, Brasil. Foram usados camundongos, adultos, albinos Swiss pesando 25-30g. Várias concentrações do EHA foram incubadas, por 30 min. a 37°C, com doses fixas da PBe (2 doses mínimas), com exceção da permeabilidade vascular, na qual foi utilizada 0,05mg/Kg da PBe. O EHA nas doses de 50 a 400 mg/Kg, via intradérmica, não inibiu o aumento da permeabilidade vascular, pelo contrário, o mesmo potencializou o referido efeito. Por outro lado, a atividade hemorrágica da PBe, via intradérmica, foi parcialmente inibida nas doses de 20 a 160 mg/Kg e abolida com 320 mg/Kg. A atividade necrosante foi completamente inibida com 290,9 mg/Kg, e parcialmente inibida nas doses de 18,2 a 145,4 mg/Kg. A atividade defibrinogenante foi parcialmente inibida pelo EHA, via intravenosa, nas doses de 125 a 220 mg/Kg, enquanto com 285 mg/Kg foi abolida. Com relação à atividade coagulante da PBe, a mesma foi parcialmente inibida nas concentrações de 20,0 a 26,6 mg/ml e abolida com 29,2 mg/ml do EHA. Resultados: A atividade fosfolipásica foi parcialmente diminuída nas concentrações de 10,0 a 80,0 mg/ml, enquanto com 160 mg/ml foi abolida. Conclusão: Os resultados sugerem que o extrato de Jatropha molissima (POHL) Baill apresenta potencial para ser utilizado no tratamento de picadas de serpentes no Nordeste do Brasil.