Reproductive dysfunction is often characterized by malfunction of the reproductive tissues, which may lead to disruption of the synergistic rhythm that should bring about a progression of sexual events and the conception of new life. This may therefore result in the sexual dysfunction and infertility that can be seen in couples having prolonged biological difficulty in reproducing their offspring after having unrestricted sexual intercourse for at least twelve months. Several factors have been implicated in the cause and progression of reproductive dysfunction, including poor nutrition, drug side effects, disease states, and toxicant ingestion. A well-known food additive that has been found to be potent at initiating reproductive anomalies in males is monosodium glutamate (MSG). This regular flavor enhancer is widely used as a taste enhancer in several diets. The different mechanisms by which it may induce reproductive dysfunctions include spermatogenic alteration resulting in a low sperm count, high sperm abnormality, reduced live sperm and decreased sperm pH, oxidative damage (increased lipid peroxidation and reduced antioxidant enzyme activities), histological alteration (blood hemorrhage, distorted germ and Sertoli cells), as well as gonadotropin imbalance (reduced testosterone, luteinizing hormone, and follicle-stimulating hormone concentrations). Therefore, this review discusses various established mechanisms through which MSG may induce reproductive dysfunction and the treatment strategies to ameliorate its toxic effects.
Keywords: antioxidant enzymes; monosodium glutamate; reactive oxygen species; reproductive dysfunction; sperm quality; testosterone.