Propriedades moleculares, atividades biológicas e imunológicas das toxinas protéicas do veneno de Brotheas amazonicus Lourenço, 1988 (Chactidae, Scorpiones)

Abstract

Scorpion venoms show a complex mixture of neurotoxic protein and peptides wich causes toxic effects in mammals and insects. Brotheas amazonicus scorpion is an abundant specimen in Manaus rural areas and feeds of insects. Clinical evidences suggest very low toxicity from his venom for humans. In this work we are introducing results about chemical composition, biological and immunological properties of toxins from B. amazonicus venom. Proteomic methods (gradient SDS PAGE, tris-tricine SDS-PAGE and 2D) showed constituents 7 and 80 kDa molecular mass range, mainly toxins with Ip 4 – 7 range. The venom showed phospholipasic A2 activity that was not inhibited by antiscorpion, antiaracnide, antilonomia, antielapidic and antiophydian antivenoms, suggesting exclusive toxin epitopes of the specie. Venom also showed serineproteases toxins with 70 kDa molecular mass, wich degradates Aα and Bβ bovine fibrinogen chain, and without fibrin coagulation. Serineproteinase activity was inhibited by antiscorpion antivenom. Bleeding and blood incoagulation was not detected in mice after intravenous venom injection. Lethal activity with 100 µg of venom was not observed in mice after intracranial and intravenous venom injection. Formalin and acetic acid test to pain induction showed that, in nervous central system level, venom toxins have a potent analgesic activity of pain of inflammatory origin but in minor level to pain of neurogenic origin, and euphoria signals were not observed. Western blotting test showed antigen-antibody interaction between B. amazonicus venom toxins and IgG antibody antiscorpionic and antiaracnide antivenoms, but both antivenoms were not detected at 7kDa venom toxins. Venom has very low toxicity in mice (mammals), and a potent analgesic activity of toxins from B. amazonicus venom suggest a high biotechnological application to development of analgesic drugs.