Banca de DEFESA: ERIVALDO DAVI DOS SANTOS JUNIOR

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ERIVALDO DAVI DOS SANTOS JUNIOR
DATE: 15/11/2021
TIME: 09:00
LOCAL: Sala 19
TITLE:

Layered double hydroxide-based nanosystem for inhibition of microRNAs:
characterization of toxicity and inhibition efficiency.

KEY WORDS:

Keywords: Layered Double Hydroxide; microRNAs; Functional Assay;
Epilepsy.

PAGES: 50
BIG AREA: Ciências Biológicas
AREA: Genética
SUBÁREA: Genética Animal
SUMMARY:

Temporal Lobe Epilepsy (TLE) is the most common epilepsy and 30% of patients do not present complete remission of seizures, even with the use of antiepileptic drugs (AEDs). Thus, there is a need to seek new therapeutic approaches, such as functional modulation of microRNAs (miRs) by pharmacological approach (MIMIC / miRs inhibitors). Layered Double Hydroxide (LDH) based nanoparticles have been used as siRNA carriers, however, the application of LDH for the delivery of miRs inhibitors still requires investigation. In this work, we produced and tested a nanocarrier based on Mg-Al-LDH complexed with miRs inhibitor against miR-196b-5p. LDHs were synthesized by coprecipitation method and subjected to physicochemical characterization regarding hydrodynamic size, surface charge, crystallinity and the chemical groups present. Regarding the biological effects, thymus endothelial cells (tEnd.1) were transfected with LDH/inhibitor and were evaluated for: i. cell viability by MTT, trypan blue and propidium iodide assays; ii. transfection efficiency by flow cytometry and iii. depletion of miR-196b-5p by RT-qPCR. In addition, Drosophila melanogaster larvae were fed LDH and were evaluated for: i. impairment of larval motility; ii. pupation rate; iii. delay to pupation; iv. lethality, and V. number of adult hatches. Finally, LNA inhibitors were used for miR-196b-5p inhibition assay in an experimental TLE model, where the relative expression of miR-196b-5p and its predicted target SLC9A6 was evaluated by RT-qPCR. We observed that LDH-type nanoparticles are stable in aqueous solutions and exhibit a regular hexagonal shape. The LDH/inhibitor complex showed a transfection efficiency of 93% and led to significant depletion of miR-196b-5p 48h after transfection. We observed no cytotoxic effects in tEnd.1 cells at concentrations up to 50 μg/ml, as well as in Drosophilas exposed up to 500 μg of LDH. In vivo functional assay in rats induced Status Epilepticus revealed a significant depletion of hippocampal levels of miR196b-5p as well as a significant increase in the relative expression of the target gene SLC9A6. In conclusion, our data suggest that LDH presents itself as a biocompatible and efficient carrier for miRNA inhibitors and can be used as a viable and effective tool in functional miRNA inhibition assays.

BANKING MEMBERS:
Presidente - 2579081 - DANIEL LEITE GOES GITAI
Interno - 1974414 - OLAGIDE WAGNER DE CASTRO
Externo à Instituição - AXEL HELMUT RULF COFRE - CESMAC