Investigation of a child-equivalent dose of monosodium glutamate toxicity in Wistar rats

Abstract

Children are more likely to consume monosodium glutamate (MSG) as this is prevalent in fast food such as fried chicken and snack food such as chip products. The aim of this study was to establish the toxic effects of higher MSG consumption in one month old Wistar rats to estimate the human equivalent dose (HED) specific to children. To understand the impact of higher MSG consumption Wistar rats were fed orally four different doses (group I-IV: 2,000 mg/kg, 4,000 mg/kg, 20,000 mg/kg and 30,000 mg/kg which with respect to HED (9 years in children), were 480 mg/kg, 960 mg/Kg, 4800 mg/Kg and 7200 mg/Kg) daily for 5 weeks compared with the control group. Histopathology was studied using Hemotoxylin and Eosin staining. The results showed an increased body weight in all MSG groups; colon with focal aberrant crypt hyperplasia noted in group IV and lymphoid cell aggregates noted in group III. The liver showed feathery degeneration and focal portal congestion were noted in all the MSG groups compared to the control groups. The kidneys showed focal congestion of blood vessels in all MSG groups. Stomach tissues exhibited no significant changes. Brain tissue sections showed congested blood vessels, and focal gliosis in group I and IV, ballooning degeneration was noted in group I, neuronal aggregates were found in group II, but group III showed no evidences of aggregates, gliosis or necrosis. This study suggests that regular and higher consumption of MSG had a deleterious impact on the organs as evident in the histology analysis and hence it is better to avoid consuming MSG containing foods especially for children.