Banca de DEFESA: EDUARDO HENRIQUE DE PAULA RIBEIRO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : EDUARDO HENRIQUE DE PAULA RIBEIRO
DATE: 01/12/2023
TIME: 14:00
LOCAL: plataforma online; Google meet; http://meet.google.com/kjo-ivns-zrt
TITLE:

Maternal melatonin absence during neurodevelopment and its relationship to Autism Spectrum Disorder: alterations in Na,K-ATPase function and oxidative stress in Wistar Rats hippocampi.

KEY WORDS:

Sodium-potassium ATPase, oxidative stress, melatonin, neurodevelopment, autism, epilepsy

PAGES: 43
BIG AREA: Ciências Biológicas
AREA: Bioquímica
SUBÁREA: Biologia Molecular
SUMMARY:

Melatonin, a hormone produced by the pineal gland, regulates the circadian cycle and acts as a powerful antioxidant. It is provided by the mother to the offspring, being crucial for proper neurodevelopment. Dysfunctions of the maternal pineal gland may increase the fetal susceptibility to autism (autism spectrum disorder, ASD). ASD manifests itself in difficulty with social interaction, repetitive behaviors and restricted interests. The hippocampus, a brain region involved in exploration and social behavior, is altered in individuals with ASD. These changes may be linked to an imbalance in the homeostasis of oxidative stress which, in turn, may modify the enzymatic activity of Na,K-ATPase. The objective of this study was to evaluate, through biomarkers of oxidative stress and Na,K-ATPase enzymatic activity, whether the absence of maternal melatonin in the gestational and postnatal periods induce biochemical changes similar to those observed in ASD in the offspring. For this, we used two Wistar rat models: pups of females that were treated with 500 mg/kg of valproic acid (VPA) i.p. on the 12.5th gestational day, as a model of autism, and puppies that developed in the absence of maternal melatonin, generated by females that had melatonin production interrupted by the removal of the pineal gland, a surgery called pinealectomy (PTX), before the gestational period. The results indicated similarities between the oxidative profile of the VPA model and PTX, in which both obtained a decrease in the levels of reduced Glutathione (GSH), but neither presented altered levels of hydrogen peroxide (H2O2) nor altered levels of peroxidation indicators, as seen by plasma membrane lipid peroxidation (TBARS). Exogenous melatonin intake was unable to change this profile. Our results indicate that the activities of total Na,K-ATPase and α1 subunit were not altered in the VPA group, however the α2,3 subunit activities were elevated. In PTX, we found an increase in total and α1 and α2,3 subunits activities, but these changes were only found in females. MEL ingestion could reverse these changes in total and α2,3 activities, but had no effect on α1 activity. Our results suggest that the absence of maternal melatonin can influence the fetal neurodevelopment process during the gestational period, through changes in the oxidative profile.

BANKING MEMBERS:
Presidente - 1716801 - CRISTIANE QUEIXA TILELLI
Externo ao Programa - 3295713 - ISRAEL JOSE PEREIRA GARCIA
Externo à Instituição - ROBINSON SABINO DA SILVA - UFU