Effectiveness of NOX3 NADPH oxidase silencing in hair cells preservation after cochlea implant

• Grant number: 14/00405-3
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2014
• End date: October 31, 2016
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal Investigator: Rubens Vuono de Brito Neto
• Grantee: Rubens Vuono de Brito Neto
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated researchers: Janaina Cândida Rodrigues ; Jeanne da Rosa Oiticica Ramalho

Abstract

Sensorineural hearing loss (SNHL) is one of the biggest public health problems in the population. The cochlear implant is indicated for bilateral profound hearing losses, being the most successful method of the present, but is associated with irreversible injury of the auditory sensory epithelium, with numerous efforts to identify methods of preservation of hair cells, amplifying, well, its indications. In cochlear implants, oxidative stress is one of the causes involved in hair cell injury, apoptosis. Thus, handling in the production of free radicals, which interferes with apoptosis pathway, represents a therapeutic strategy that can be tested in order to promote otoprotection. The NOX3 oxidase is an enzyme family of NADPH oxidase, generating free radical superoxide, the organ of Corti. Objectives: This study aims to evaluate whether primary introduction of shRNA NOX3 via cochleostomy reduce enzyme expression NOX3 induced by the introduction of the cochlear implant electrode in a secondary objective was to evaluatethe degree of apoptosis in these cells as well as its morphology and concentration of BAX. Methodology: 105 shall be used guinea pigs (Cavia porcellus) 210 cochlea of both sexes weighing between 250 and 350g divided into three groups after normal otoscopic examination and testing auditory evoked potential > 40dB. In the study group (EG) 150 cochlea receive the shRNA silencing of NOX3 NADPH oxidase, via cochleostomy, eight days before the placement of the cochlear implant, and used 5 different clones for the same gene. Placebo group, 30 underwent insertion of the cochlea scramble shRNA (empty), cochleostomy via the implant group (GI), 30 cochleas submitted to cochlear implantation only without previous injection. In all groups of 30 cochlea (ratio) 20 will be used to test real-time PCR (RT-PCR), and 10 to assay for detection of apoptosis, which method is a fluorescence microscopy using antibody rat IgG2b class M30 Cytodeath. Statistical analysis will be through their means and standard deviations, and quantitatively analyzed using Student's t test and analysis of variance (ANOVA) for paired samples. It is statistical significance level of 5 % (p < 0.05). (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

RODRIGUES, JANAINA C.; BACHI, ANDRE L. L.; SILVA, GLEICIELE A. V.; ROSSI, MARCELO; DO AMARAL, JONATAS B.; LEZIROVITZ, KARINA; DE BRITO, RUBENS. New Insights on the Effect of TNF Alpha Blockade by Gene Silencing in Noise-Induced Hearing Loss. INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES, v. 21, n. 8, APR 2020. (14/00405-3)