Non-nutritive Sweetener Aspartame Disrupts Circadian Behavior and Causes Memory Impairment in Mice

Abstract

As a non-nutritive sweetener, aspartame is widely used in everyday life. However, its safety is highly controversial, especially its effects on neurobehavior. We evaluated the effects of chronic daily oral administration of aspartame-containing drinking water (at doses equivalent to 7−28% of the FDA-recommended human DIV) on memory and rhythm behaviors in mice and further investigated changes at the molecular level in the brains. Our results demonstrated that mice exposed to aspartame exhibited memory impairment. Disorders of hippocampal neurotransmitter metabolism and pathological damage may be responsible for the aspartame-induced memory impairment via inhibition of the BDNF/TrkB pathway. Furthermore, our findings suggested that disturbed clock gene expression in the hypothalamus after aspartame exposure led to altered rest−activity behavior, and this disruption of the circadian rhythm may exacerbate memory impairment. This study highlights the negative neurobehavioral effects of aspartame and provides valuable insights into its rational and safe use.