Banca de DEFESA: RAFAEL CAETANO LISBOA CASTRO DE ANDRADE

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : RAFAEL CAETANO LISBOA CASTRO DE ANDRADE
DATE: 11/05/2021
TIME: 14:00
LOCAL: Link de acesso para videoconferência: https://meet.google.com/sgh-xbyy-pbo
TITLE:

Production and characterization of chitooligosacarides, evaluation of its healing and antinflammatory action

KEY WORDS:

Biocompatibility; Oligosaccharides; Chitosan; Enzymatic Hydrolysis; in vivo tests;

PAGES: 73
BIG AREA: Ciências da Saúde
AREA: Farmácia
SUMMARY:

The skin integrity is essential for human life. When a rupture occurs in this physical barrier, the purpose of the repair mechanism is to induce a quick and efficient response to avoid complications such as keloid formation or progression to a chronic wound. In this scenario, the demand for the search for biomolecules, with antioxidant, antimicrobial, anti-inflammatory and immunostimulating characteristics, such as chitooligosaccharides (COSs), which can assist in the healing process, must be accelerated. Therefore, this study aims to produce COS, in two times of hydrolysis (1 and 5 minutes) by chitosanases derived from Bacillus toyonensis, to carry out structural characterization, to evaluate biocompatibility in acute toxicity models in vivo and cytotoxicity, and healing action in cell migration models (“scratch”) in vitro and in vivo wound repair. The chitosan enzymatic degradation process produced oligosaccharides with a deacetylation degree about 80%, with a hexamers predominance attributed through the gel permeation technique chromatography (GPC) and proven in the analysis mass spectrometry. The acute toxicity test confirms the nontoxicity of these substances and cell viability indicates the oligosaccharides biocompatibility on murine fibroblasts. The QOS ability to stimulate fibroblast migration in vitro was observed in all tested tools (100; 250; 500 µg/mL), with a reduction up to 100% in the groove size 12 hours after adding a concentration of 500 µg/mL COS obtained with 5 minutes hydrolysis. The oligosaccharides in vivo healing effect was confirmed in the surgical wound-induced model, where these molecules reduced for the groups tested with COS1 30 mg/kg (89.25% ± 2.2), COS1 300 mg/kg (82% ± 10.6), COS5 30 mg/kg (89.25% ± 1.7) and COS5 300 mg/kg (93% ± 0.8) when compared to saline group (61.25% ± 8.1) without the seventh day of the experiment. Despite having no known mechanism of action, the hexamers presence may be related to the biological effects of COS. Thus, the selected results indicate the COS potential use as a healing for the pharmaceutical field.

BANKING MEMBERS:
Interno - 3652554 - FRANCISCO CANINDE DE SOUSA JUNIOR
Externa à Instituição - MARIA GIOVANA BINDER PAGNONCELLI - UTFPR
Presidente - 1544647 - MATHEUS DE FREITAS FERNANDES PEDROSA