Biochemical characterization of a phospholipase A2 homologue from the venom of the social wasp Polybia occidentalis

Background: Wasp venoms constitute a molecular reservoir of new pharmacological substances such as peptides and proteins, biological property holders, many of which are yet to be identified. Exploring these sources may lead to the discovery of molecules hitherto unknown. This study describes, for the first time in hymenopteran venoms, the identification of an enzymatically inactive phospholipase A2 (PLA2) from the venom of the social wasp Polybia occidentalis. Methods: P. occidentalis venom was fractioned by molecular exclusion and reverse phase chromatography. For the biochemical characterization of the protein, 1D and 2D SDS-PAGE were performed, along with phospholipase activity assays on synthetic substrates, MALDI-TOF mass spectrometry and sequencing by Edman degradation. Results: The protein, called PocTX, was isolated using two chromatographic steps. Based on the phospholipase activity assay, electrophoresis and mass spectrometry, the protein presented a high degree of purity, with a mass of 13,896. 47 Da and a basic pI. After sequencing by the Edman degradation method, it was found that the protein showed a high identity with snake venom PLA2 homologues. Conclusion: This is the first report of an enzymatically inactive PLA2 isolated from wasp venom, similar to snake PLA2 homologues.

Pharmacological characterization of cnidarian extracts from the Caribbean Sea: evaluation of anti-snake venom and antitumor properties

Background: Cnidarians produce toxins, which are composed of different polypeptides that induce pharmacological effects of biotechnological interest, such as antitumor, antiophidic and anti-clotting activities. This study aimed to evaluate toxicological activities and potential as antitumor and antiophidic agents contained in total extracts from five cnidarians: Millepora alcicornis, Stichodactyla helianthus, Plexaura homomalla, Bartholomea annulata and Condylactis gigantea (total and body wall). Methods: The cnidarian extracts were evaluated by electrophoresis and for their phospholipase, proteolytic, hemorrhagic, coagulant, fibrinogenolytic, neuromuscular blocking, muscle-damaging, edema-inducing and cytotoxic activities. Results: All cnidarian extracts showed indirect hemolytic activity, but only S. helianthus induced direct hemolysis and neurotoxic effect. However, the hydrolysis of NBD-PC, a PLA2 substrate, was presented only by the C gigantea (body wall) and S. helianthus. The extracts from P. homomalla and S. helianthus induced edema, while only C gigantea and S. helianthus showed intensified myotoxic activity. The proteolytic activity upon casein and fibrinogen was presented mainly by B. annulata extract and all were unable to induce hemorrhage or fibrinogen coagulation. Cnidarian extracts were able to neutralize clotting induced by Bothrops jararacussu snake venom, except M. alcicornis. All cnidarian extracts were able to inhibit hemorrhagic activity induced by Bothrops moojeni venom. Only the C. gigantea (body wall) inhibited thrombin-induced coagulation. All cnidarian extracts showed antitumor effect against Jurkat cells, of which C. gigantea (body wall) and S. helianthus were the most active; however, only C. gigantea (body wall) and M. alcicornis were active against B16F10 cells...

Biochemical characterization of a phospholipase A2 homologue from the venom of the social wasp Polybia occidentalis

Wasp venoms constitute a molecular reservoir of new pharmacological substances such as peptides and proteins, biological property holders, many of which are yet to be identified. Exploring these sources may lead to the discovery of molecules hitherto unknown. This study describes, for the first time in hymenopteran venoms, the identification of an enzymatically inactive phospholipase A2 (PLA2) from the venom of the social wasp Polybia occidentalis. Methods: P. occidentalis venom was fractioned by molecular exclusion and reverse phase chromatography. For the biochemical characterization of the protein, 1D and 2D SDS-PAGE were performed, along with phospholipase activity assays on synthetic substrates, MALDI-TOF mass spectrometry and sequencing by Edman degradation. Results: The protein, called PocTX, was isolated using two chromatographic steps. Based on the phospholipase activity assay, electrophoresis and mass spectrometry, the protein presented a high degree of purity, with a mass of 13,896. 47 Da and a basic pI. After sequencing by the Edman degradation method, it was found that the protein showed a high identity with snake venom PLA2 homologues. Conclusion: This is the first report of an enzymatically inactive PLA2 isolated from wasp venom, similar to snake PLA2 homologues.(AU)

Pharmacological characterization of cnidarian extracts from the Caribbean Sea: evaluation of anti-snake venom and antitumor properties

Cnidarians produce toxins, which are composed of different polypeptides that induce pharmacological effects of biotechnological interest, such as antitumor, antiophidic and anti-clotting activities. This study aimed to evaluate toxicological activities and potential as antitumor and antiophidic agents contained in total extracts from five cnidarians: Millepora alcicornis, Stichodactyla helianthus, Plexaura homomalla, Bartholomea annulata and Condylactis gigantea (total and body wall). Methods: The cnidarian extracts were evaluated by electrophoresis and for their phospholipase, proteolytic, hemorrhagic, coagulant, fibrinogenolytic, neuromuscular blocking, muscle-damaging, edema-inducing and cytotoxic activities. Results: All cnidarian extracts showed indirect hemolytic activity, but only S. helianthus induced direct hemolysis and neurotoxic effect. However, the hydrolysis of NBD-PC, a PLA2 substrate, was presented only by the C gigantea (body wall) and S. helianthus. The extracts from P. homomalla and S. helianthus induced edema, while only C gigantea and S. helianthus showed intensified myotoxic activity. The proteolytic activity upon casein and fibrinogen was presented mainly by B. annulata extract and all were unable to induce hemorrhage or fibrinogen coagulation. Cnidarian extracts were able to neutralize clotting induced by Bothrops jararacussu snake venom, except M. alcicornis. All cnidarian extracts were able to inhibit hemorrhagic activity induced by Bothrops moojeni venom. Only the C. gigantea (body wall) inhibited thrombin-induced coagulation. All cnidarian extracts showed antitumor effect against Jurkat cells, of which C. gigantea (body wall) and S. helianthus were the most active; however, only C. gigantea (body wall) and M. alcicornis were active against B16F10 cells. Conclusion: The cnidarian extracts analyzed showed relevant in vitro inhibitory potential over the activities induced by Bothrops venoms; these results may contribute to elucidate the possible mechanisms of interaction between cnidarian extracts and snake venoms.(AU)

Antileishmanial activity of 3-(3,4,5-trimethoxyphenyl) propanoic acid purified from Amazonian Piper tuberculatum Jacq., Piperaceae, fruits / Atividade antileishmania do 3,4,5-trimetoxi-dihidrocinâmico purificado das frutas de Piper tuberculatum Jacq., Piperaceae, amazônica

Leishmanicidal activity of the 3-(3,4,5-trimethoxyphenyl) propanoic acid (TMPP) isolated from EtOH extracts of the Amazonian Piper turbeculatum Jacq. fruits was evaluated in vitro using Leishmania amazonensis promastigotes. The TMPP was assayed at concentrations of 1600 to 6.25 µg/mL for 24, 48, 72 and 96 h. Promastigotes viability was analyzed and the IC50 of TMPP was 145 µg/mL.

A atividade leishmanicida do ácido 3,4,5-trimetoxi-dihidrocinâmico (TMPP) isolado do extrato hidroalcoólico de frutos de Piper turbeculatum Jacq. amazônica foi testado em ensaios in vitro utilizando formas promastigotas de Leishmania amazonensis. O TMPP foi utilizado em culturas de L. amazonensis nas concentrações de 1600 a 6,25 µg/mL. A viabilidade celular das formas promastigotas foi observada em 24, 48, 72 e 96 h para cálculo da CI50. O TMPP apresentou efeito leishmanicida dose dependente para as formas promastigotas de L. amazonensis apresentando CI50 de 145 µg/mL.