The effect of monosodium glutamate on the cerebellar cortex of male albino rats and the protective role of vitamin C (histological and immunohistochemical study)

Abstract
Monosodium glutamate (MSG) is a natural constituent of many foods and was reported to have neurotoxic effects. The aim of this study was to investigate the possible toxic effect of MSG on histological and glial fibrillary acidic protein (GFAP) immunohistochemical features of cerebellar cortex of albino rats and to evaluate the possible protective role of vitamin C against this effect. Thirty rats were divided into 3 equal groups. Group I, control; Group II, treated with 3 g/kg/day of MSG and Group III, received 100 mg/kg/day of vitamin C simultaneously with MSG. After 14 days, cerebellar tissues were obtained and processed to prepare sections stained with H&E, toluidine blue. The GFAP was detected immunohistochemically. Histological examination of group II showed degenerative changes as pyknotic Purkinje and granule cells with areas of degeneration surrounded by inflammatory cells in granular layer. However, group III showed more preserved histological structure of cerebellar cortex. Statistical analysis of area percent of the GFAP immunoreaction among studied groups showed significant increase in group III when compared with group I and group II. However, a non significant increase was detected in group II when compared with group I. In conclusion, MSG has neurotoxic effect leading to degenerative changes in neurons and astrocytes in cerebellar cortex of albino rats and vitamin C supplementation could protect from these changes. Getting more attention to the constituents of food products is recommended and vitamin C could be advised to protect people from food oxidants additives.