Cell death induction of dibutyl phthalate (DBP) on primary brain cells from adult zebrafish

Abstract

The presence of phthalates as plasticizer on pharmaceutical products as well as in aquatic environments requires serious attention. Phthalates are compounds widely used in the manufacturing industry and has been associate with multiple adverse health effects to human. Among the family of phthalates Dibutyl phthalate (DBP) is well used for pharmaceutical products. Limited information however has been generated on the effect of DBP on the brain. The objective of this investigation was to characterize potential neurotoxicity resulting from short term exposure to DBP. Considering the efficacy and sensitivity of the zebrafish model as an early stage- screening tool, and their neurological and biochemical similarities to those of human, this study evaluates the effect of DBP on primary brain cells of the adult zebrafish. This well optimized and implemented methodology can be consider a guide for future studies using primary cells of adult zebrafish given the reduction on reagents, and the number of cells used for treatment. For indirect confirmation of extracted nervous tissue, the Acetylcholinesterase activity (AChEs) assay kit was implemented. In our study primary cells from adult zebrafish brain were exposed to DBP for 24 hours at aerobic environment at concentrations from 3uM to 100μM. The effect on cell viability as well as cell death mechanisms was determined. Results indicate that adult primary brain cells viability is compromised as low as 8uM of DBP. In terms of mechanism, cells undergo apoptosis and autophagy at concentrations of 8μM and 100μM. This study confirms that low concentrations of DBP over a 24-hour period induces apoptosis and autophagy, potentially activating degradation of brain cells and altering biochemical processes of the nervous system. This research presents a novel approach for future molecular studies using brain primary cells as model to screen pharmaceuticals and environmental agents for risk assessment.