CELLULAR EFFECTS OF LOW-DOSE MONOSODIUM GLUTAMATE ON HIPPOCAMPAL SUB FIELDS IN FEMALES ADULTS WISTAR RAT

ABSTRACT Monosodium glutamate (MSG), a widely used food additive, has raised growing concerns regarding its potential neurotoxic effects, particularly in relation to chronic, low-dose exposure. This study investigates the cellular and histological impacts of low-dose MSG on the hippocampal subfields—CA1, CA3, and dentate gyrus (DG)—in adult female Wistar rats. Fifteen rats were randomly divided into three groups: a control group receiving saline and two experimental groups receiving low-dose MSG (4 g/kg) orally for 60 days. Following treatment, brain tissues were processed and stained using Hematoxylin & Eosin (H&E) and Cresyl Fast Violet (Nissl) stains to assess structural alterations and neuronal integrity. Histological findings from the control group revealed well-preserved cytoarchitecture with densely packed pyramidal and granule cells. However, MSG-treated groups exhibited dose-dependent histopathological changes, including neuronal shrinkage, pyknotic nuclei, vacuolation, reduced Nissl substance, and disrupted hippocampal organization. Group C rats showed more severe alterations, such as neuronal loss, gliosis, and pronounced structural disintegration. These changes were most notable in the CA1 and DG subfields, indicating region-specific vulnerability to excitotoxic injury. The results suggest that chronic exposure to low-dose MSG induces subtle yet progressive neurodegenerative changes in the hippocampus, potentially impairing cognitive functions such as memory and learning. This study underscores the need for cautious dietary intake of MSG and supports further research into its long-term effects on brain health, especially in female populations