Auramine O, food dye induces cognitive impairment, anxiety, alters synaptic transmission and neural growth in zebrafish model

Synthetic food dyes, widely used to enhance the visual appeal of food and beverages, are associated with potential neurobehavioral impacts, particularly in children. Despite its banned status in many regions, Auramine O (AO) has been detected as a contaminant in various food products. In silico studies have demonstrated that AO can induce neurotoxic effects. Zebrafish were exposed to varying concentrations of AO (5 and 10 mg/L) and acrylamide at 100 mg/L in the positive control (PC) group. Behavioral tests (Novel Object Recognition, Open Field Test, Light-Dark Test, Novel Tank Test, T-maze Test), enzymatic assays, histological analysis, and gene expression studies were conducted. Staining assays such as dichlorodihydrofluorescein diacetate (DCFH-DA) for reactive oxygen species (ROS), acridine orange for apoptosis, thioflavin for amyloid plaques, alizarin red s for calcification, and AO accumulation in brain tissue were conducted using High-Performance Liquid Chromatography (HPLC) analysis. AO exposure led to dose-dependent cognitive impairment, anxiety-like behaviors, decreased enzymatic marker levels, increased ROS levels, apoptosis, amyloid plaques, and calcification. Gene expression analysis revealed the upregulation of stress and inflammation-related genes and the downregulation of antioxidant and neuroprotective genes. HPLC confirmed AO accumulation in brain tissue. AO induces significant neurotoxicity in zebrafish, with higher concentrations causing more pronounced effects. These findings raise concerns about potential neurotoxic impacts on humans, particularly children, and highlight the need for stringent regulatory measures.