Banca de QUALIFICAÇÃO: MIGUEL TABANEZ

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : MIGUEL TABANEZ
DATA : 30/03/2022
HORA: 09:30
LOCAL: Santo André
TÍTULO:

Metal analysis in vitro and in vivo models of Alzheimer's disease and effects of the antioxidant hydroxytyrosol

PÁGINAS: 35
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
SUBÁREA: Química Inorgânica
ESPECIALIDADE: Química Bio-Inorgânica
RESUMO:

[13:08, 25/02/2022] Miguel: With the increase in life expectancy of the general population, the incidence of neurodegenerative diseases increases, making it increasingly possible to know someone who is affected.
Alzheimer's disease (AD) is commonly known to affect the memory of those diagnosed with it, but other symptoms can reduce the quality of life of those diagnosed. Even though it has been studied for years, we do not know the molecular responses to this disease's biochemistry sporadically. A consequence and/or aggravating AD is the deregulation of metallic levels in cells and organs. This work aims to elucidate metallic levels by inductively coupled plasma mass spectrometry (ICP-MS) in in vitro and in vivo models that present molecular responses similar to AD. It is also proposed to use the antioxidant hydroxytyrosol (HT, 4-(2-hydroxyethyl)benzene-1,2-diol), a metabolic derivative of oleuropein present in olive leaves and olive oil, to study its effects on metal dysregulation. and behavioral studies in animals. For in vitro models, mouse hippocampal cells were used with amyloid beta oligomer (oAβ1-42). TH showed a return to baseline levels of copper and calcium in cells. In vivo models, Wistar rats were used with intracerebroventricular (ICV) injections of streptozotocin (STZ), a molecule capable of decreasing cell glucose uptake and causing biochemical and behavioral effects similar to AD in animals. It was observed that the use of STZ caused a decrease in blood plasma cobalt concentration, which is also reported in humans diagnosed with AD.

On the other hand, previous treatment by ICV injection with HT before STZ prevented the decrease in Co concentration. In brain tissue, treatment with STZ in the hippocampus showed an increase in calcium and iron concentration. In both cases, the HT treatment before ICV injection of STZ also prevented this increase, showing effectiveness in the antioxidant treatment in cell protection. The frontal cortex showed a rise in copper and calcium concentrations with STZ treatment to cause neurodegeneration. Still, the use of HT before STZ increased the calcium concentration while reducing the basal level of copper. In the behavioral analysis by Barnes maze, animals with only STZ injections covered a greater distance in only one of the training trials than the control group and with HT treatment before STZ. In the final Barnes maze test, the group of animals with HT treatment before STZ increased the percentage of exploration on target compared to the group with STZ. Still, it was not possible to notice another significant difference in other parameters. The results showed an attenuating effect, that is, a return to normality, of the proposed treatment with TH on metallic levels in vitro and in vivo neurodegeneration models. In the frontal cortex, responsible for memory and spatial orientation, an increase in Cu was observed in the treatment with STZ and a return to normality when HT is used before neurodegenerative treatment. There was an increase in metallic levels of Ca from the frontal cortex and Co from the hippocampus, in which the TH treatment worsened the difference between the control group and STZ injection. The percentage of exploration in the target was the only parameter in which the injection of HT before the STZ was able to smooth the difference between the group of STZ injection and the control. These results can demonstrate that the injection of HT only presented benefits to spatial memory.

MEMBROS DA BANCA:
Presidente - Interno ao Programa - 1544365 - GISELLE CERCHIARO
Membro Titular - Examinador(a) Interno ao Programa - 1933328 - HELOISA FRANCA MALTEZ
Membro Titular - Examinador(a) Externo ao Programa - 1994696 - SILVIA HONDA TAKADA
Membro Suplente - Examinador(a) Interno ao Programa - 1844792 - AMEDEA BAROZZI SEABRA
Membro Suplente - Examinador(a) Interno ao Programa - 1623774 - KARINA PASSALACQUA MORELLI FRIN
Membro Suplente - Examinador(a) Externo ao Programa - 1872537 - MARCELA BERMUDEZ ECHEVERRY