Antoine_2026_IBRO.Neurosci.Rep_20_643

BACKGROUND: Monosodium glutamate (MSG), a common food additive, is known to enhance taste and flavour. However, increasing evidence suggests that elevated MSG intake is linked to neuronal pathologies and death. Tabernaemontana stapfiana is a plant traditionally used in Cameroon for multiple purposes, including as a haemostatic, an anthelmintic, and in the treatment of rheumatism, kidney disorders, rickets, and conjunctivitis. Notably, traditional practitioners also use it to address nervous system disorders, drug addiction, and memory impairments, highlighting its potential as a neuroprotective agent. This study aimed to evaluate the neuroprotective effects of the aqueous extract of the stem barks from this plant on MSG-induced neurotoxicity in mice. METHODS: This study was carried out using 49 Swiss albino mice, classified into seven groups of 7 mice each. The negative control group (group 1) received distilled water (10 mL/kg) throughout this experiment. The positive control group received MSG (2 g/kg) and distilled water (10 mL/kg). Reference standard 1 (RS1) received vitamin C (100 mg/kg) and reference standard 2 (RS2) received donepezil (3 mg/kg). Doses 1, 2, and 3 groups received MSG concomitantly with aqueous extract of T. stapfiana (250, 500, and 1000 mg/kg respectively) for 10 days. Monosodium glutamate was administered intraperitoneal (i.p) while treatments were orally administered (p.o). Behavioural parameters such as Y-maze, elevated plus maze, open field and wire suspension tests were evaluated on days 8, 9, and 10 using various tests. After 10 days, biomarkers of oxidative stress and acetylcholinesterase activity were evaluated in the brain. RESULTS: MSG induced oxidative stress, poor muscle coordination, and spatial short-term memory impairment in mice. The T. stapfiana extract prevented these MSG-induced behavioural changes. The extract also alleviated oxidative stress and reduced acetylcholinesterase activity in the brains of the animals. CONCLUSION: Results suggest that T. stapfiana aqueous extract prevents neurotoxicity, possibly through its free radical scavenging ability and the maintenance of acetylcholinesterase activity in a mouse model of MSG-induced neurotoxicity.