Banca de DEFESA: RAFAEL OLIVEIRA DE ARAÚJO COSTA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : RAFAEL OLIVEIRA DE ARAÚJO COSTA
DATE: 30/05/2023
TIME: 09:00
LOCAL: Sala de Reuniões (DNUT)/UFRN e Videoconferência - Link para ac: https://meet.google.com/vgd-wqrn-hbe
TITLE:

Encapsulation of proteins and peptides with anti-obesity properties: study of the effect of trypsin inhibitor isolated from tamarind seeds on weight change and satiety

KEY WORDS:

Nanotechnology; Nanoparticles with proteins; trypsin inhibitor; Stability; Storage.

PAGES: 101
BIG AREA: Ciências Biológicas
AREA: Bioquímica
SUMMARY:

Obesity drives the search for new strategies to combat it. In this sense, several peptides and proteins with satietogenic activity have been studied because they regulate dietary intake and body weight. Thus, this thesis is divided into two chapters. First, we sought to understand how peptides and proteins, when encapsulated, acted on satiety, impacting weight gain and the state of obesity. For this, an integrative review was carried out by searching databases, using the keywords: peptide, protein, obesity, encapsulation, and anti-obesity agents, and selecting preclinical studies that compared the effect of peptides or proteins, encapsulated or not, on satiety. A total of 836 studies were selected, of which only four articles met the review's focus under the selection criteria. Although it has been a limited number of studies, among the effects observed with the encapsulation of these molecules are the greater efficiency in reducing weight gain, changes in the function of adipose tissue, in addition to the reduction of hormone levels that modulate appetite and body weight, promoting the potentiation of the effects of these peptides and proteins when encapsulated. In the second chapter, the impact of the trypsin inhibitor isolated from tamarind seeds (TTI) was investigated compared to the same one, nanoencapsulated in chitosan and isolated whey protein (EQPI). Thus, the ECW was analyzed and exposed to different pH conditions (7.0, 3.0, and 7.0) and temperatures (37°C, 7°C and -18°C) to evaluate the interaction between the TTI and its encapsulating agents monitored by antitrypsin activity. Subsequently, a preclinical study was carried out in which Wistar rats (n = 25) with obesity induced by a high glycemic index and high glycemic load (HGLI) diet for 17 weeks were divided into five groups and evaluated for ten days, with them: no treatment (HGLI + water), treatment 1 (nutritionally adequate diet), treatment 2 (with nutritionally adequate diet and ECW/12.5 mg/kg), treatment 3 (diet HGLI and ECW/12.5 mg/kg ) and treatment 4 (diet HGLI and TTI/25 mg/kg). These groups were evaluated for dietary intake, zoometric, biochemical, and inflammatory parameters. The ECW preserved the TTI, showing no inhibition for trypsin efficiently. When subjected to the optimal condition (constant stirring at 300 rpm, for approximately 12 h, at 20°C) for the release of the TTI, it showed 100% antitrypsin activity. However, exposing ECW to different pHs, significant anti-trips activity was observed only at gastric pH for 2 h. And regarding exposure to temperatures, ECW showed high antitrypsin activity, similar to TTI (37°C for 4 h, 7°C for three days, and 7°C for 7 days), demonstrating the complete release of TTI contained in ECW. In the preclinical study, obese Wistar rats treated with ECW significantly reduced body weight change (p < 0.05) compared to treatment with TTI. It was observed that only TTI treatment led to significant changes in inflammatory parameters (p < 0.05). The effect of ECW on weight indicates that encapsulation promoted an increase in the impact of TTI with sustained release. Therefore, the encapsulation of peptides and proteins is a promising strategy for the applicability of these molecules in the treatment of diseases such as obesity.

COMMITTEE MEMBERS:
Presidente - 2578619 - ANA HELONEIDA DE ARAUJO MORAIS
Externo ao Programa - 1639820 - ARNOBIO ANTONIO DA SILVA JUNIOR - nullExterna à Instituição - Catarina Gonçalves - INL
Externa à Instituição - PRISCILLA VANESSA FINOTELLI - UFRJ
Externa ao Programa - 1452705 - SEVERINA CARLA VIEIRA CUNHA LIMA - nullExterna ao Programa - 2275877 - THAIS SOUZA PASSOS - null