Monosodium glutamate (MSG) is a flavor enhancer. Its toxicity in a malnourished state appears not to have been fully investigated. This study was carried out to determine the effects of MSG on malnourished rats. Rats were randomly assigned into four groups of five rats/group. Groups containing malnourished rats and normal rats were given feeds containing 1.6 mg/g MSG while the other two groups containing only malnourished rats and the normal healthy respectively were given normal feeds for 28 days. After 28 days, the rats were sacrificed with the liver harvested and blood samples collected. Results from the study showed that malnourished rats had significantly lower levels oxidative stress biomarkers including, anti-oxidants compared with the control. Malondialdehyde concentration and xanthine oxidase activity in malnourished rats were although not significantly high compared to the normal healthy, high malondialdehyde concentration and xanthine oxidase activity was observed in the malnourished fed rats. Aspartate aminotransferase and Alanine transaminase levels of malnourished and normal rats administered with MSG were significantly low compared to the normal healthy suggesting that labialization occurs in liver leading to leakage of these enzymes from the liver to the serum. Malnourished rats showed significant body weight decrease losing 48 grams after 28 days compared to malnourished and normal rats fed with MSG which recorded significant increase in body weight after 28 days adding 26 g and 42 g respectively.

Keywords: monosodium glutamate (MSG); hepatic; antioxidant; oxidative stress.