2-Ethylhexyl diphenyl phosphate aggravates colitis-induced neuroinflammation and behavioral abnormalities by inhibiting the PI3K-AKT-NF-κB and Wnt/GSK3β signaling pathways.

2-Ethylhexyl diphenyl phosphate (EHDPHP), a widely used organophosphorus flame retardant (OPFR), is ubiquitous in daily life because of its extensive application in plastic production. EHDPHPs, which are only superficially applied and not chemically bonded to products, are released into the environment, posing potential health risks. With increasing environmental concentrations, EHDPHP is a growing threat, particularly to individuals with preexisting health conditions who are more susceptible to environmental pollutants. This study examined the effects of EHDPHP exposure in a colitis model, reflecting a rising chronic health issue, by assessing changes in neuroinflammation and neurobehavioral abnormalities. Healthy and dextran sulfate sodium (DSS)-induced colitis C57BL/6 J mice were treated with either 0.2 % Tween or EHDPHP solution (10 mg/kg body weight/day) for 28 days. The study revealed significant increases in the serum and expression levels of TNFα and IL-1β, accompanied by depressive and anxiety-like behaviors. Coexposure to EHDPHP and DSS exacerbated these neurobehavioral impairments. RNA sequencing confirmed that EHDPHP triggered inflammation via the PI3K-Akt-NF-κB and Wnt/GSK3β signaling pathways, as confirmed by Western blot analysis. These findings suggest that EHDPHP aggravates colitis-induced neuroinflammation and neurobehavioral abnormalities, highlighting the harmful impact of EHDPHP, particularly in individuals with preexisting inflammatory conditions.