Monosodium glutamate-induced genotoxicity in rat palatal mucosa

Abstract

Background Monosodium glutamate (MSG) is an accepted commonly used flavor enhancer and food additive. However, incautious abuse of this food additive may occur because of its abundance, mostly without labeling, in many food ingredients. Objective The objective of this study was to investigate the genotoxic potential of MSG on rat palatal mucosa. Materials and methods Forty-two mature albino rats weighing 200–250 g at the age of 6 weeks were used in this study. They were allocated to evenly three groups, each group of 14 animals. Group I was maintained as control group. Rats in group II and group III were administered MSG at two different doses, 20 and 40 mg/kg body weight respectively for 2 months. Palatal mucosa samples were dissected then divided into two halves. The first half was fixed in formal saline solution then processed to be stained with hematoxylin and eosin stain. The second half was frozen to be prepared for the molecular study. Results General histological examination presented acanthosis and hyperkeratosis in group II while group III revealed papillary fold projections and bulbous shaped rete pegs together with atypical cellular changes in the basal cell layer of the oral epithelium. Molecular results proved marked reduction in DNA quality and quantity in both experimental groups in comparison to control group. The reduction in DNA quantity was more pronounced in group III using four different primers. Conclusion It was concluded that MSG has genotoxic effects on the palatal mucosa of rats that was clearly detected in routine histological findings and DNA molecular results.