Banca de QUALIFICAÇÃO: MENILLA MARIA ALVES DE MELO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : MENILLA MARIA ALVES DE MELO
DATE: 26/02/2021
TIME: 09:00
LOCAL: Videoconferência
TITLE:

TanP, a anionic peptide from Tityus stigmurus scorpion venom with metal chelating, antioxidant, anticoagulant, immunomodulatory and healing properties

KEY WORDS:

Anionic peptide. Chelating. Antioxidant. Peptide TanP. Tityus stigmurus.

PAGES: 126
BIG AREA: Ciências da Saúde
AREA: Farmácia
SUMMARY:

Anionic peptides, or acids, of scorpions correspond to the class of peptides without disulfide bonds, rich in aspartic and / or glutamic acid residues in their primary sequence. TanP is a linear anionic peptide, with 50 amino acid residues and net charge -20, which is present in the venom gland of the scorpion Tityus stigmurus, identified by a transcriptomic approach and after confirmed by mass spectroscopy. A previous study indicated that TanP has a chelating potential for Cu (II) ion, in addition to an immunomodular potential. The therapeutic application of chelating molecules is related to cases of acute or chronic intoxication by metals, neurodegenerative diseases, hematological diseases, healing of skin wounds, cardiovascular diseases and cancer. This work evaluated TanP chelating activity in relation to new metals of biological importance was carried out, as well as expanding the investigation of the biological potential of the peptide, as an antioxidant, hemostatic, immunomodulatory and wound healing molecule. UV-visible spectroscopy and fluorescence were used to evaluate the chelating activity of TanP in the presence of Fe (II), Ca (II) and Zn (II) ions. Biological activities were determined by in vitro assay. TanP (25 μM) was able to form stable complexes with Fe (II) in a ratio of 1: 5 (TanP: Fe2+). The fluorescence intensity of TanP (1.12 μM) decreased significantly after the addition of Fe (II), obtaining that the highest ratio 1: 7.4 (TanP: Fe2+) led to the lowest fluorescence intensity. TanP showed a maximum of 3% of hemolytic activity when evaluated at the highest concentration (50 μM). TanP exhibited DPPH radical scavenging above 70% at all concentrations tested (1 to 25 μM), 94% iron chelating activity at 50 μM, 96% hydroxyl radical scavenging activity at 73.6 μM. TanP showed significant anticoagulant activity at concentrations of 12.5 μM and 25 μM for the TP and TTPa assays. No fibrinogenolytic effect was observed. TanP (12.5 and 25 μM) induced release of TNF-α by murine macrophages, in the absence of LPS, this increase being dose-dependent. The migration of 3T3 cells was stimulated by TanP (2 μM, 12.5 μM and 50 μM) in an in vitro healing assay. Thus, it is believed that the assessment of the chelating potential associated with the antioxidant, anticoagulant, immunomodulatory and healing effects of TanP supports further studies that enable the development of a prototype molecule for therapeutic and biotechnological applications.

BANKING MEMBERS:
Externa ao Programa - 2378605 - CRISTIANE FERNANDES DE ASSIS
Presidente - 1893445 - EUZEBIO GUIMARAES BARBOSA
Interna - 1055045 - MARCELA ABBOTT GALVAO URURAHY