Adil MARDİNOĞLU, Hasan TÜRKEZ, Özlem ÖZDEMİR TOZLU, Kenan ÇADIRCI

The in vitro cytotoxic, genotoxic, and oxidative damage potentials of the oral artificial sweetener aspartame on cultured human blood cells

Background/aim: Aspartame (APM, L-aspartyl-L-phenylalanine methylester) is a low-calorie, nonsaccharide artificial sweetener widelyused in foods and beverages. When metabolized by the body, APM is broken down into aspartic acid, phenylalanine amino acids, and a thirdsubstance, methanol. Since the amino acid phenylalanine serves as a neurotransmitter building block affecting the brain, and methanol isconverted into toxic formaldehyde, APM has deleterious effects on the body and brain. Thus, its safety and, toxicity have been the subjectsof concern ever since it was first discovered. Although many studies have been performed on it, due to the presence of conflicting data in theliterature, there are still numerous question marks concerning APM. Therefore, the safety of aspartame was tested using in vitro methods.Materials and methods: We aimed to evaluate the in vitro cytotoxic effects by using 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) and lactate dehydrogenase release tests, genotoxic damage potential by using chromosome aberration (CA) assay, andantioxidant/oxidant activity by using total antioxidant capacity (TAC) and total oxidative stress (TOS) analysis in primary human wholeblood cell cultures.Results: The results of the MTT test showed that APM led to significant decreases in cell viability in a clear concentration-dependentmanner. Moreover, an increase in CA frequency was found in the cells treated with APM. However, APM treatments did not cause anysignificant changes in TAC and TOS levels in whole blood cultures.Conclusion: Overall, the obtained results showed that APM had genotoxicity potential and a concentration-dependent cytotoxic activityin human blood cells.

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