Banca de DEFESA: RAISSA COUTO SANTANA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : RAISSA COUTO SANTANA
DATE: 20/09/2023
TIME: 13:00
LOCAL: https://conferenciaweb.rnp.br/sala/lucia-helena-pinto-da-silva
TITLE:

Analysis of the immunomodulatory activity  of natural and synthetic compounds in different lineages of murine and canine macrophages

KEY WORDS:

Leishmania amazonensis, Treatment, immunomodulatory activity

PAGES: 116
BIG AREA: Ciências Agrárias
AREA: Medicina Veterinária
SUBÁREA: Medicina Veterinária Preventiva
SPECIALTY: Doenças Parasitárias de Animais
SUMMARY:

Macrophages are phagocytic cells of the innate immune system present in several organs, composing a cell population involved in homeostasis and tissue protection. Macrophages can differentiate, according to the microenvironment, into cells capable of eliminating pathogenic microorganisms or into cells capable of restoring the balance of damaged tissue. Their plasticity highlighted them as targets of several drugs capable of orientate their response to numerous diseases. Leishmaniasis is a set of clinical manifestations that afflict 1 million people annually in lack of financial and health conditions. Macrophages are the host cells of the parasite Leishmania sp. harboring amastigotes that multiply until they disrupt the cell, thus establishing the infection. The treatment for this disease are toxic and expensive, making consumption and distribution on a large scale unfeasible. Natural products are an easily accessible, low-cost and safe option with pharmacological activities and their chemical structure allows modifications for their improvement. We evaluated the immunomodulatory activity of 3 natural products (-)-Guaiol, Piperine (AF1), 1,8-cineole and a synthetic piperine derivative: N4-cyclohexyl-1,2,4-triazol-3- thione (AF2) in different macrophages strains of murine P388D1 and RAW 264.7 and canine DH82. The compounds demonstrated a dose-dependent leishmanicidal activity in vitro for Leishmania amazonensis promastigotes with IC50 of 56.24 µM, 9.36 µM and 8.73 µM for (-)-Guaiol, AF1 and AF2, respectively. The cell lines showed viability above 70% in the treatments with the compounds (-)-Guaiol, AF1 and AF2. Preliminary results demonstrate that AF2 and 1,8-cineole at a concentration of 50 µM decreased the phagocytic activity of the DH82 after incubation with promastigotes. In RAW 264.7 cells stimulated with LPS, treatments with the compounds increased the production of nitric oxide (NO). In DH82, it is possible to observe a decrease in NO production in nonstimulated cells treated with (-)-Guaiol, different from the treatment with AF2 and 1,8- cineole, which increased in relation to the control. The murine strain P388D1 stimulated with LPS, where treatments with (-)-Guaiol and 1,8-cineole decreased NO production, while AF2 led to an increase in NO. ROS production in RAW 264.7 cultures without stimulus and treated with AF1, AF2 and 1,8-cineole increased ROS production in relation to control. In RAW 264.7 cultures stimulated with LPS, ROS production decreased after AF2 treatment. In LPS-stimulated P388D1, treatment with (-)-Guaiol and AF1 decreased ROS production. The DH82 cells decreased its ROS production in AF1 and increase in AF2. In stimulated cells, treatment with AF1 and 1,8-cineole led to a decrease while with (-)-Guaiol there was an increase in ROS production. The analysis of MHC and costimulatory molecules of RAW 264.7 murine macrophages stimulated or not with LPS+INF-γ and treated, did not show alteration in the expression of MHC II, CD80 and CD86. Preliminary results demonstrate that the compounds tend to decrease MHC II expression in unstimulated and LPS-stimulated DH82 cells. In P388D1 there was a decrease in the population of MHC I + cells treated with 60 µM of AF2 and AF2+LPS and an increase in the population of MHC II+ cells treated with AF2, AF2+LPS and infected with L.a and treated with AF2. Finally, real-time PCR results demonstrate that murine RAW 264.7 and canine DH82 macrophages increased mRNA expression of the cytokine IL-10 after treatment with (-)-Guaiol, AF1 and 1,8-cineole. Expression of IL10, IL-12, TLR4 and TLR9 in RAW 264.7 and DH82 cells decreased after treatment with the compounds. The unstimulated P388D1 cell line treated with (-)-Guaiol and AF1 led to a reduction of TLR4 expression in the cells. The results imply that the effect of the compounds may be different depending on the cell type and that they can modulate the production of NO, ROS and the expression of inflammatory and anti-inflammatory cytokines as well as altering the expression of MHC and Toll like receptors (TLR) in cells.

COMMITTEE MEMBERS:
Presidente - 1545840 - LUCIA HELENA PINTO DA SILVA
Interna - 1222756 - DEBORA DECOTE RICARDO DE LIMA
Interna - 1792175 - PATRICIA FAMPA NEGREIROS LIMA
Externa à Instituição - EVELIZE FOLLY DAS CHAGAS - UFF
Externo à Instituição - LEONARDO FREIRE DE LIMA - UFRJ
Externo à Instituição - RENATO PORROZZI - FIOCRUZ
Externa à Instituição - VERONICA FIGUEIREDO AMARAL - UFF