Banca de DEFESA: MARIA LAURA DE SOUZA LIMA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : MARIA LAURA DE SOUZA LIMA
DATE: 21/03/2024
TIME: 14:00
LOCAL: meet.google.com/yrx-irdd-jaj
TITLE:

ROLE OF ANGIOTENSIN II AT1 AND AT2 PHARMACOLOGICAL RECEPTORS IN LIGATURE-INDUCED PERIODONTAL DISEASE: MOLECULAR ASPECTS

KEY WORDS:

Angiotensin II; Receptor AT1;Receptor  AT2; Periodontal disease;

PAGES: 50
BIG AREA: Ciências da Saúde
AREA: Odontologia
SUBÁREA: Periodontia
SUMMARY:

The renin angiotensin system (RAS) is of great importance for the body's water balance and blood pressure regulation, in addition to being associated with the stimulation of pro-inflammatory pathways. Its main peptide is angiotensin II, which interacts mainly with type 1 (AT1) and type 2 (AT2) receptors. An interrelationship was found between cardiovascular diseases and periodontitis. This study aimed to evaluate the molecular aspects in knockout mice subjected to an experimental model of periodontal disease, observing the influence of Ang II type 1 (AT1(-)) and Ang II type 2 (AT2(-)) receptors on periodontitis. . Methods: Experimental periodontitis was induced by placing a ligature with 5.0 nylon suture around the upper left second molar of knockout mice for AT1(-), AT2(-) receptors and wild-type (Wild-Type, WT), subdivided 2 groups for each strain: without ligation (NL) and ligation (L), totaling six groups: three controls and three experimental. After 15 days of disease induction, the animals were euthanized. In order to evaluate whether genetic variations would have an influence on periodontal disease, analyzes of cytokines were carried out, peptides and enzymes were analyzed from gingival tissues by ELISA and RT-PCR. Results: The WT and AT2(-) animals showed similar results in relation to the cytokines IL-1β, IL-6, TNF-α, in which the linked animals increased the levels of these cytokines in relation to the healthy ones (p < 0.001), since animals from the AT1(-) lineage showed no differences between sick and healthy animals, but showed some differences in relation to other lineages: in the cytokine IL-β we identified significant differences in relation to the AT1(-)-L and WT-L groups (p < 0.05), in IL-6 and TNF-α, the AT1(-)-L groups showed significant differences (p < 0.001) both when compared to the WT-L and AT2(-)-L groups . Regarding the IL-10 cytokine, WT animals expressed higher levels in the ligated group (p < 0.01), the AT2(-) and AT1(-) groups did not show significant changes in relation to this cytokine. For the results of Angiotensin II and Angiotensin 1-7 there were significant differences when comparing the AT2(-)-NL and AT2(-)-L groups (p < 0.01); and in relation to the AT1(-)-L and AT2(-)-L groups (p < 0.05) in the Ang 1-7 results, in relation to the other groups there were no significant differences. For TLR2 there were differences between the WT-NL/WT-L groups (p < 0.05); AT1(-)-NL/AT1(-)-L (p < 0.01) and AT2(-)-NL/AT2(-)-L (p < 0.01). For the MAS receptor, there were differences between the WT-NL/WT-L (p < 0.001) and AT2(-)-NL/AT2(-)-L (p < 0.001) groups. Among the different lines in the linked subgroup there was also a statistical difference in relation to the WT-L/AT1(-)-L group (p < 0.001) and AT1(-)-L/AT2(-)-L (p < 0.001). For the expression of the ACE peptide, or ACE, there was a statistical difference between the types of WT-NL/WT-L groups (p < 0.001). For the expression of the ACE2 peptide, or ACE2, no statistically significant differences were obtained. Conclusion: The animals in the AT1(-) group showed less inflammation than the other diseased strains, as well as a lower expression of the MAS receptor, also responsible for a protective pathway against the RAS. Furthermore, animals from the WT and AT2(-) groups demonstrated similar results in several analyses, showing that the blockade of the AT1 receptor, on molecular effects, is more positive.

COMMITTEE MEMBERS:
Presidente - 2374605 - AURIGENA ANTUNES DE ARAUJO
Interna - 2085732 - ANA RAFAELA LUZ DE AQUINO MARTINS
Externa ao Programa - 2477216 - NAISANDRA BEZERRA DA SILVA FARIAS - UFRNExterna à Instituição - KARUZA MARIA ALVES PEREIRA - UFC
Externo à Instituição - RAFAEL RODRIGUES LIMA - UFPA