Comparative study of Crotalus durissus terrificus snake venoms born in captivity i...
| Grant number: | 16/03311-5 |
| Support type: | Scholarships in Brazil - Scientific Initiation |
| Effective date (Start): | January 01, 2017 |
| Effective date (End): | December 31, 2018 |
| Field of knowledge: | Biological Sciences - Physiology |
| Principal Investigator: | Anita Mitico Tanaka-Azevedo |
| Grantee: | Lidia Jorge Tasima |
| Home Institution: | Instituto Butantan. Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil |
Abstract The Brazilian reptile fauna consists of 760 species, divided into Testudines, Crocodylia and Squamata, belonging the last one are the "Lizards" (260 spp.), Amphisbaenia (72 spp.) and snakes (386 ssp.). There are several families of snakes, among them the Viperidae family, which has representatives in Brazil. Its main feature is its solenoglyphous inoculant device and traditionally assigned four subfamilies with living representatives: Viperinae, Causinae, Azemiopinae and Crotalinae. The Crotalinae subfamily is characterized by the presence of loreal pit located bilaterally between the eye and the nostril. In Brazil there are five genera, among them are Bothrops, Bothriopsis, Bathrocophias, Crotalus and Lachesis. The genus Crotalus snakes have a rattle at the end of the tail, and only Crotalus durissus species occurs in Brazil, with five subspecies described. The venom of C. durissus has three activities with known clinical importance: neurotoxic activity, myotoxic and coagulant. After fractioned, the venom has four main fractions: crotoxin, convulxin, gyroxin and crotaline. The crotaline is a small cationic peptide and its main action is neurotoxic. It also causes depolarization of skeletal muscle cells, tetanic contractions without sync, acetylcholine and dopamine release in rats, and a potent analgesic activity. His amphipathic structure proved to be important to check several of its biological effects, as its antimicrobial activity, antimalarial, antitumor, leishmanicide and anthelmintic. The native crotaline is supported by three disulfide bridges, imparting high stability in its 3D structure, comprising on a small N-terminal alpha helix and a small antiparallel beta sheet triple chain. This structure is common to beta-defensin and defensin alpha-mammals. Due to its small size and its amino acid configuration occurs a charge distribution on the surface of the molecule which allows crotaline a single cell penetration property, allowing to use it as carrier molecules into cells. The venom of C. durissus has great variability, which may be yellow or white; and crotalin may be present (positive crotaline) or absent (negative crotaline) in its composition. The crotalin positive poison or crotaline-negative have different mechanisms of action and the venom containing crotaline is viewed with importance in the production of antivenom. The more complete the better venom is the variability and the spectrum of action for antivenom treatment. The aim of this study is to analyze the presence of crotaline the venom of snakes Crotalus durissus terrificus, Crotalus durissus collilineatus and Crotalus durissus cascavella squad and newcomers at the Butantan Institute, verify its efficiency in the production of antivenom and analyze its relationship with the geographic distribution of these animals. (AU) | |