Banca de DEFESA: Vanessa Nicolau de Lima

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : Vanessa Nicolau de Lima
DATE: 01/03/2024
TIME: 14:00
LOCAL: Auditório do IB
TITLE:

"DEVELOPMENT OF A NANOPARTICLE-MEDIATED PHOTOHYPERTHERMIA PROTOCOL TO PROMOTE INFERTILITY IN MALE ANIMALS".

KEY WORDS:

Male sterilization, nanocastration, magnetic nanoparticles, photothermal therapy.

PAGES: 103
BIG AREA: Ciências Biológicas
AREA: Biologia Geral
SUMMARY:

An overpopulation of stray animals is a global issue, raising concerns about uncontrolled reproduction and risks to public health. Nanotechnology presents potential for castration through nanoparticle-mediated photohyperthermia (NHT), showing promise for animal population control. The aim of this study was to assess the effect of testicular photohyperthermia mediated by maghemite nanoparticles coated with citrate and gold (NPAu) and citrate-functionalized manganese ferrite nanoparticles (NPCit) on the reproductive parameters of Wistar rats. A total of 49 Wistar rats (approximately 10 weeks old) were used. NHT treatment involved intratesticular injection of 150 μL of fluid (NPAu or NPCit) combined with LED irradiation to achieve a temperature of approximately 45°C for 15 minutes. Reproductive parameter evaluations were conducted up to 56 days, the time required for complete spermatogenesis in rats. Results indicated that testicular NHT mediated by NPAu led to progressive damage to reproductive parameters, including reduced testicular volume and percentages of motile and morphologically normal sperm, as well as the number of sperm in the epididymal tail. Additionally, histopathological evaluation of testicles at 7, 28, and 56 days posttreatment revealed progressive damage to seminiferous tubules. However, intact seminiferous tubules were still present at the end of the assessments, suggesting incomplete effects. Testicular NHT mediated by NPCit initially showed similar results to NPAu; however, it was identified that intact seminiferous tubules were located at the periphery of the testicles, even with the presence of nanoparticle clusters in the region. This finding suggested inefficient light penetration into the tissue, possibly not reaching nanoparticles on the opposite side of LED incidence. Therefore, a new device with 2 LEDs was used for NPCit-mediated NHT, and the results demonstrated more homogeneous destruction of seminiferous tubules. Histopathological analysis revealed irreversible damage to spermatogenesis, worsening progressively over time. Additionally, spermatic parameters and testicular morphometry were also negatively affected. In all cases, regardless of the nanoparticle used, there was no pain or compromised weight gain in the animals, and the histology of the liver, spleen, kidneys, and lungs was not affected by the procedure. In conclusion, the application of nanoparticle-mediated photohyperthermia (NPCit and NPAu) directly to the testicles resulted in significant harmful effects on the reproductive parameters of rats in a short-term period (56 days), proving to be a promising procedure for inducing infertility in male animals.

COMMITTEE MEMBERS:
Externo à Instituição - ALEXANDRE FLORIANI RAMOS - EMBRAPA
Presidente - 2374060 - CAROLINA MADEIRA LUCCI
Externo ao Programa - 1515568 - MARCIO BOTELHO DE CASTRO - nullInterna - 2220195 - MONICA PEREIRA GARCIA
Externo à Instituição - PAULO CESAR DE MORAIS - UCB