Banca de QUALIFICAÇÃO: MAYARA SANTA ROSA LIMA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : MAYARA SANTA ROSA LIMA
DATE: 09/09/2021
TIME: 14:00
LOCAL: Videoconferência
TITLE:

ANTI-INFLAMMATORY EFFECT OF PEPTIDES AND PROTEINS ON THE INTEGRITY AND FUNCTIONALITY OF THE INTESTINE BARRIER

KEY WORDS:

Amino Acids, Peptides and Proteins. Anti-Inflammatory Agents. Tumor Necrosis Factor Alpha. Intestinal Mucosa. Systematic review.

PAGES: 88
BIG AREA: Ciências Biológicas
AREA: Bioquímica
SUMMARY:

A healthy intestinal barrier protects the individual against the translocation of microorganisms and other antigens, ensuring a controlled inflammatory environment. This thesis is divided into three chapters, the first and second referring to a systematic review (SR), whose objective was to understand the mechanisms of action of anti-inflammatory molecules that reduce TNF-α and its effects on the intestinal barrier in murine models. The protocol presented in the first chapter was registered in the International Prospective Register of Systematic Reviews (PROSPERO), and guided the methodological procedures used to prepare the systematic review, presented in the second chapter. Articles that were part of the SR were selected considering the eligibility criteria according to the PICOS (population, interventions, control and results) and were searched in databases PubMed, Scopus, Web of Science, Excerpta Medica Database (EMBASE) and ScienceDirect. Thirty-one articles were selected and the risk of bias was assessed using the SYstematic Review Center for Laboratory Animal Experimentation (SYRCLE) tool. It was found that the anti-inflammatory molecules that acted by reducing TNF-α acted mainly on signaling pathways TNF-TNFR1/TNFR2 and TLR4/MD2 complex, and consequently on the NF-κB pathway, which improved the symptoms of the inflammatory diseases studied, in addition to the macroscopic, histological and intestinal permeability aspects. In the third chapter, a study with the trypsin inhibitor isolated from tamarind seeds (TTI) is presented, aiming to evaluate the effect of this inhibitor on hematological, biochemical and inflammatory parameters and on the integrity and functionality of the intestinal barrier in an experimental model of obesity and in cell culture. For the study in animals, Wistar rats with obesity (n=15) were divided into three groups: untreated group (n=5), group treated with nutritionally adequate diet (n=5) and group treated with ITT (25 mg/ kg/day, n=5) for ten days. At the end of the experiment, the in vivo intestinal permeability was evaluated using the mannitol lactulose test; the animals' blood was obtained to verify hematological and biochemical parameters, in addition to the plasma concentrations of TNF-α and IL-6; and the small intestine was collected for histopathological, histomorphometric and TNF-α and tight junctions proteins expression evaluation. The cell study will evaluate the expression of inflammatory cytokines, tight junction proteins and mucin-2 in co-culture of Caco-2:HT29-MTX cells previously inflamed and treated with ITT. The results of the animal experiment showed that rats with obesity treated with TTI had significantly lower plasma concentrations of inflammatory cytokines than the other groups (p<0.05), in addition to better histopathological and histomorphometric results in the intestine, although there was no significant differences between groups regarding most semiquantitative parameters and intestinal permeability. The results regarding the expression of proteins in the intestine of animals, as well as the results of studies in cell culture, are still being obtained and evaluated.

BANKING MEMBERS:
Interna - 1549705 - ADRIANA FERREIRA UCHOA
Externa ao Programa - 2646462 - BRUNA LEAL LIMA MACIEL
Externa ao Programa - 349432 - LUCIA DE FATIMA CAMPOS PEDROSA