Monosodium Glutamate: Mechanisms of Action and Role in the Development of Structural Changes of Organs and Systems (Literature Review)

Abstract

The purpose of the study was to analyze the available published data on the effects of monosodium glutamate on structure and function of different organs and systems of a living organism, as well as the role of monosodium glutamate in the development of certain pathologic conditions. Special attention was dedicated to the data pertaining the reported morphological manifestations of monosodium glutamate unfavorable effects on cardiovascular, digestive and reproductive systems, as well as metabolic processes. Data about suspected genotoxicity of monosodium glutamate was also analyzed with the effects on cancerogenesis in focus. Careful attention was paid to general design of specific studies, doses of monosodium glutamate administered and the rout of administration applied to facilitate estimation of relevance and clinical significance of the data obtained in any given study. Materials and methods. The search was done in the databases of Google Scholar, NCBI, PUBMED and Web of Science using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis PRISMA) Guidelines. The depth of the search was 10 years but several older papers that were significant for understanding the background of the monosodium glutamate research were also included. Results and discussion. Monosodium glutamate is a flavor enhancer that is widely used and is consumed by adults and children on a daily basis. Despite monosodium glutamate is generally considered to be safe for consumption and is permitted for use in many countries, numerous studies have shown its various toxic effects on organs and tissues that resulted in impaired structure and function. That is why scientific research on monosodium glutamate effects on the structure and function of certain organs and systems of a living organism remains relevant, especially given the variety and somewhat ambiguity of the data available. Available evidence of monosodium glutamate induced morphological changes has special clinical significance, as it is the structural disturbances that are the main underlying cause of impaired functions that result in development of pathologic processes and diseases. So determination of relevance and estimation of quality of the data available is crucial for its interpretation and determination of its possible clinical extrapolation. Conclusion. The data shows that monosodium glutamate consumption may be associated with adverse effects, particularly with cardiotoxicity, hepatotoxicity, neurotoxicity, metabolic disorders, obesity, diabetes mellitus, chronic inflammation, behavioral changes and even genotoxicity. However, taking into account different design and methodology of the studies and various doses of monosodium glutamate administered, certain difficulties that arise while extrapolating the studies’ results to wider population and their sometimes limited clinical application point towards the need for further research and generalizations on the effects of short-term and long-term administration of various doses of monosodium glutamate and their effects on molecular, biochemical and structural levels