Dose-dependent neurotoxic effects of monosodium glutamate on neural tube development in chicken embryos

Considering the excitatory neurotransmitter role of glutamate in the central nervous system and the widespread use of monosodium glutamate (MSG) as a food additive, this study aimed to evaluate the effects of MSG on neural tube defect formation in chicken embryos.

In this study, fertile, specific pathogen free eggs were used. Dosage calculation was based on the provisional tolerable intake of MSG of 30 mg/kg body weight per day reported in the literature. Doses were calculated as Group A: saline, Group B: 30 mg/kg, Group C: 60 mg/kg. Monosodium glutamate was dissolved in sterile distilled water to the desired concentrations.

The effects of MSG on neural tube development were evaluated in chicken embryos. In the control and low-dose (30 mg/kg) groups, the neural tube and notochord were largely intact, with only minor irregularities and a single neural tube defect observed. In contrast, embryos in the high-dose group (60 mg/kg) displayed neuroectodermal separation, luminal irregularities, and multiple neural tube defects with prominent openings. The difference in the incidence of neural tube defects between the groups was statistically significant (p = 0.021), indicating a dose-dependent adverse effect of MSG on neural tube development.

MSG, a commonly used food additive, was found to impair neural tube development in chicken embryos in a dose-dependent manner, suggesting a potential risk during early embryogenesis.