The Effects of Monosodium Glutamate Consumption on Oral Glucose Tolerance Test (OGTT) in Rats

Abstract

Background and Objective: Monosodium glutamate (MSG) is a sodium salt of glutamic acid, widely used as a food additive both in household and food industry. An injection of MSG into newborn mice causes of several metabolic disorders such as obesity, non-alcoholic fatty liver disease and type 2 diabetes. We aimed to investigate the effect of MSG consumption on glucose regulation in adult rats.

Methods: Twenty adult male Wistar rats were randomly divided into control and treatment groups. Both groups were fed ad libitum with a standard rat chow pellet and water, except the treatment group were received MSG (2 mg/g body weight/day) in drinking water for nine months. Oral glucose tolerance tests (OGTT) were investigated. Water intake, food intake and body weight were also recorded.

Results: There were no significant differences in OGTT results between control and MSG-treated animals. MSG-treated rats had significantly higher water intake compared to controls. However there were no significant differences in food intake and body weight between control and MSG-treated animals.

Conclusion: The results revealed that daily MSG consumption with the dose of 2 mg/g body weight /day for nine months had no effect on OGTT, an index of glucose regulation, in adult rats.

Key words: monosodium glutamate, oral glucose tolerance test, islets of Langerhans