Impact of artificial sweeteners on cellular growth and signaling pathways

Abstract

Artificial sweeteners such as saccharin, acesulfame, aspartame, neotame, and sucralose are found in a wide variety of foods today, particularly in zero‐calorie sugar substitutes (Equal, Sweet’ N Low, Splenda). Research conducted on animals and human epidemiological studies involving use of these compounds have provided contradictory results, in some cases indicating the compounds as safe and in others, as causing cancer. In our project, we sought to analyze the impact of six different synthetic sugar substitutes (found in Whole Earth, Equal, Splenda, Sweet’ N Low, Nutrasweet and Nutame) on bacterial and mammalian cell growth. The commercial substitutes as well as the purified ingredients found in these substitutes (erythritol, xylitol, stevia, monkfruit extract) were both tested. In this two‐phase project, E. coli cells were grown on minimal media lacking glucose but supplemented with the substitutes to determine the impact on growth. Bacterial cells were exposed to 0.4% of the compounds (0.4% is the standard glucose concentration found in rich LB media) and grown on media plates as well as in liquid cultures. Positive controls included minimal media plates containing glucose as well as rich media LB plates; negative controls included minimal media plates lacking any sugars. Our results indicate that bacteria are able to metabolize the sweeteners at different capacities but are unable to grow in acelsulfame‐K as well as the Whole Earth sweetener. A dose‐dependent profile to monitor whether bacteria will be able to utilize these compounds at higher doses (>0.4%) or will be able to survive if exposed to much lower doses (<0.1%) indicated that the growth increased with increasing concentration of the sweetener until 1%. In the second phase of our study we are growing mammalian normal (HEK293) and cancer cell lines in the presence of these substitutes at different concentrations and analyzing the impact specifically on the the mTOR signaling pathway that has been linked to a wide variety of cancers. Since some sugar substitutes have been linked to cancers in animals (e.g. sucralose to bladder cancer in rats) and considering the enormous use of these sweeteners today, this study will provide useful findings that could have important implications for their continued usage.Support or Funding InformationThis work is being supported by a UNIV498 Faculty‐Student Collaborative Research Award from CSU, Channel Islands to Nitika Parmar