Chronic dietary tartrazine exposure leads disability in brain function through behavioural alteration and sex drive reduction in-vivo zebrafish: A translational model for human health risk assessment.

Tartrazine, an extensively used synthetic food dye has raised concerns related to its potential neurotoxic effects, especially during critical periods of neurodevelopment. This study evaluated the chronic neurobehavioral, molecular, neuroendocrine, and histopathological effects of tartrazine exposure in zebrafish from the juvenile stage to adulthood, which mimics the human developmental period from childhood through adolescence. Zebrafish were chronically exposed to tartrazine ranging from environmentally relevant concentrations to the minimal lethal concentration (0.75 µg/L to 5 mg/L) for 140 days. After exposure period, behavioral alterations, neurochemical levels, oxidative stress markers, reproductive efficiency and gene expression profiles were evaluated. Brain tissues were examined histologically and immunohistochemically for the expression of α-synuclein, β-amyloid, and GFAP. Study result revealed that tartrazine exposure induced significant behavioral disturbances with alteration of neurotransmitter levels (increased AChE activity, depleted dopamine and GABA levels) and marked oxidative stress. Gene expression analysis revealed an upregulation of inflammatory and apoptotic markers with downregulation of neurodevelopmental and synaptic genes. Histological findings indicated pronounced neurodegeneration with glial disruption and proteinopathies characterized by β-amyloid and α-synuclein aggregation. Sex drive disruption was evident through reduced fecundity and elevated brain testosterone in female. Results highlight the potential risks associated with prolonged tartrazine intake, warranting further investigation and safety regulation for human society.