In Vivo and In Vitro Studies Assessing the Safety of Monosodium Glutamate

The controversial results of research on monosodium glutamate demand a new data corpus for the overall safety evaluation. Both animal and cellular model systems have been used to add a multilevel scope on its biological effects. The Drosophila melanogaster animal model has been used to test a wide range of concentrations for safety purposes: toxicity, genotoxicity, longevity and health span. Medium concentrations corresponding to the human acceptable daily intake (ADI) (0.06 mg/mL) were not toxic nor genotoxic for Drosophila and safe for the lifespan parameters. Once safety was determined, the possible nutraceutical effects of monosodium glutamate was monitored in terms of antitoxicity, antigenotoxicity assays and health span. The results for protective activity against hydrogen peroxide were positive in terms of the medium concentration, antitoxic and antigenotoxic in terms of inhibiting the genotoxicity induced by the oxidative toxin up to 43.7% and increasing the health span expectancy by 32% in terms of days. Monosodium glutamate has been demonstrated to be cytotoxic against the model tumour cell line HL-60, not only in a necrotic way but through internucleosomal DNA fragmentation antitumour activity. The significant LINE1 DNA sequence methylation of HL-60 tumour cells induced by monosodium glutamate is a molecular marker for chemoprevention. Conclusions: the slight or non-significant positive nutraceutical and chemo preventive potential showed by monosodium glutamate at its ADI concentration can be considered as a safe dose for a moderate consumption.