Banca de QUALIFICAÇÃO: Juliana Amorim dos Santos

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : Juliana Amorim dos Santos
DATE: 29/09/2022
TIME: 14:00
LOCAL: Plataforma Teams
TITLE:

Modulating the PI3K-PTEN-AKT-mTOR pathway in the wound healing of oral mucositis models

KEY WORDS:

Mucosite oral; via PI3K-PTEN-AKT-mTOR; modelo in vitro; reparo tecidual

PAGES: 100
BIG AREA: Ciências da Saúde
AREA: Odontologia
SUMMARY:

INTRODUCTION: Oral mucositis (OM) is a prevalent adverse reaction in individuals undergoing antineoplastic therapy and safe and efficient therapeutic strategies are necessary. In this context, modulators of the PI3K-PTEN-AKT-mTOR pathway may be potential alternatives. OBJECTIVE: To evaluate the modulation of the PI3K-PTEN-AKT-mTOR signaling pathway in healing process using oral mucositis models. METHODOLOGY AND PARTIAL RESULTS: To date, two in vitro models were established. For the first one, monoculture of immortalized human keratinocytes and primary culture of human gingival fibroblasts were used with three stimuli: lipopolysaccharide from Escherichia coli (LPS), protein extract from Porphyromonas gingivalis (Pg) and ionizing radiation (IR). For the second model, the same stimuli were applied in co-cultures with transwell inserts to enable cellular interaction between keratinocytes and fibroblasts through the secretion of chemical mediators. To evaluate the effects of modulating the PI3K-PTEN-AKT-mTOR pathway, the models were treated with curcumin, BpV(pic) and photobiomodulation. So far, the effects have been evaluated by viability test, morphological analysis, healing assay and cell migration. For the establishment of the OM model, the stimuli of greater cytotoxicity were induced by the association of the three components (LPS + Pg + IR), with a statistically significant result in keratinocytes (p<0.001). In fibroblasts, although greater resistance to stimuli was observed, the combination of the three stimuli is essential to generate cellular aggression, when compared to isolated ionizing radiation (p<0.05) and isolated bacterial stimulus (p<0.001). Subsequently, in the first monoculture model, curcumin treatment increased fibroblast viability (p<0.01), lesion closure (p<0.05) and nuclear area (p<0.005), and reduced the cytoplasmic area of keratinocytes (p<0.05). BpV(pic) increased fibroblast viability (p<0.05), nuclear area (p<0.0001), lesion closure (p<0.005) and vimentin expression. In association, it reduced the cytoplasmic area of keratinocytes (p<0.001). Photobiomodulation was also able to increase cell viability in both keratinocytes (p<0.05) and fibroblasts (p<0.05) and wound closure only in fibroblasts (p<0.05). For the second coculture model, fibroblasts showed a better response than keratinocytes after treatments. Photobiomodulation accelerated lesion closure in fibroblasts (p<0.05). However, this treatment tended to reduce lesion closure in keratinocytes after 48 hours. Thus, the treatments induced cell proliferation and the repair process in in vitro models of oral mucositis, mainly in fibroblasts. Keratinocytes seem to be more susceptible to aggression and less responsive to treatments, also presenting a more heterogeneous response. The results highlight the importance of well-established models for the further study of oral mucositis. Furthermore, it reinforces the hypothesis that modulators of the PI3K-PTEN-AKT-mTOR pathway can be effective adjuvant treatments in the management of this lesion. NEXT STEPS: Thus, for the analysis and confirmation of the interest pathways signaling, the next steps of this project foresee the performance of gene expression experiments by real-time polymerase chain reaction (qPCR) and protein expression by Western blot (PI3K, PTEN, AKT, mTOR, NFκB, TNFα, IL-6, IL-1β) in the established models, in addition to the development of new oral mucositis models with 3D culture and ex-vivo animal.

BANKING MEMBERS:
Externo à Instituição - CINTHIA GABRIEL MEIRELES - MS
Presidente - 1278451 - ELIETE NEVES DA SILVA GUERRA
Externo à Instituição - RICARDO DELLA COLETTA - UNICAMP
Interna - 768.449.191-15 - TAIA MARIA BERTO REZENDE - UFMG