Banca de DEFESA: JÉSSICA REBOUÇAS SILVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : JÉSSICA REBOUÇAS SILVA
DATE: 29/07/2022
TIME: 09:00
LOCAL: IGM Sala Virtual 5
TITLE:

Evaluation of leishmanicidal and immunomodulatory effects of natural compounds on Leishmania spp. Infection

KEY WORDS:

Leishmaniasis, Cutaneous; Leishmania; Natural compounds; Amphotericin B; Propolis; Yangambin; Epi-yangambin; Nanocarriers

PAGES: 158
BIG AREA: Ciências Biológicas
AREA: Biologia Geral
SUMMARY:

ABSTRACT
Cutaneous leishmaniasis (CL) is a serious public health concern. Due to lacking commercial interest, the current therapeutic arsenal is outdated and presents serious limitations. The present study employed nanotechnological tools and explored the biodiversity of Brazilian flora to evaluate four possible candidates for CL therapy: Nanostructured Lipid Carriers containing Amphotericin B (CLN-AnB), Standardized Brazilian green propolis extract (EPP-AF®) and the yangambin and epi-yangambin lignans in in vitro and/or in vivo models of L. amazonensis or L. braziliensis infection, both etiological agents of CL in Brazil. In vitro assays revealed the rapid uptake of CLN-AnB by macrophages after 1h of treatment, contributing to reduced cytotoxicity and a leishmanicidal effect at low concentrations, in the absence of TNF-𝛼 or nitric oxide production. Similar efficacy was observed between the CLN-AnB and meglumine antimoniate treatments with respect to lesion reduction and decreased parasite burden in L. braziliensis-infected BALB/c mice. On the other hand, L. amazonensis-infected macrophages treated with EPP-AF® modulated the production of pro- and anti-inflammatory mediators, in addition to activating the ERK 1/2 signaling pathway, while also reducing infection index. Furthermore, topical treatment with EPP-AF® gel resulted in reduced lesion size in L. amazonensis-infected BALB/c mice in the absence of reduced parasite load or altered systemic inflammatory mediator production, as well as in the lymph nodes or at the site of infection (ear dermis). Finally, the leishmanicidal and immunomodulatory effects of yangambin and epi-yangambin were demonstrated for the first time in both L. amazonensis- and L. braziliensis-infected macrophages. In sum, this project possesses the innovative potential to identify novel candidates for CL therapy, in addition to furthering the search for bioactive compounds in the context of Brazilian biodiversity.

BANKING MEMBERS:
Externo à Instituição - FLÁVIA RAQUEL FERNANDES DO NASCIMENTO - UFMA
Externa à Instituição - CECILIA BEATRIZ FIUZA FAVALI - UnB
Interna - 011.952.725-10 - NATALIA MACHADO TAVARES - UFBA
Externa à Instituição - TATIANA RODRIGUES DE MOURA - UFS
Presidente - 028.288.917-55 - VALÉRIA DE MATOS BORGES - UFRJ