Combined with High-Fat Diet, PFOS Exposure Impacts Neurodevelopment in Mice

PFOS can affect several brain functions including memory, coordination, and social activity. Similarly, diets high in fat can impair cognition and increase risk for dementia. In a recent study published in part by the STEEP team, research investigated combined impacts of a high-fat diet (HFD) and PFOS exposure on weight gain, behaviors associated with autism spectrum disorders (ASD), attention deficit hyperactivity disorder (ADHD), and dementia.

The analysis for the effects of PFOS/HFD was based on the brains of adult mice. Pregnant mice were acquired for four exposure groups, and litters of 6-8 pups were tracked with their mothers. Randomized pups were fed a HFD or standard chow, and then again randomly exposed to ionized water or a PFOS mixture. Behavior studies included timed maze trials and subsequent runs to test memory retention, as well as “open field” tests, in which rearing, distance traveled, and time in the center of the “field” was recorded.

Results showed that females exposed to PFOS alone showed an increase in weight, and HFD expectedly increased body weight. Combined HFD and PFOS increased rearing and time in the “field”, impacting social behavior, while PFOS alone impacted distance, suggesting that PFOS may promote hyperactivity.

Consistent with behavioral observations, genomic analysis of the brain showed that PFOS exposure affects brain functions and processes, and overall, may reprogram the genome and development, promoting symptoms linked to ASD and ADHD.

Researchers acknowledge sex differences may exist in the effects of PFOS and HFD, and methods may not have been sensitive enough to detect learning and memory impairment; other cognitive tests should be used in the future. More investigation into markers of ASD and ADHD may offer strong evidence for the link between PFOS, HFD and those disorders.

Hmila, I., Hill, J., Shalaby, K.E., Ouararhni, K., Abedsselem, H., Modaresi, S.M.S., Bihaqi, S.W., Marques, E., Sondhi, A., Slitt, A.L., Zawia, N.H. 2024. Perinatal exposure to PFOS and sustained high-fat diet promote neurodevelopmental disorders via genomic reprogramming of pathways associated with neuromotor development. Ecotoxicology and Environmental Safety, 2024 272, 116070. [DOI: 10.1016/j.ecoenv.2024.116070]