The role of propylparaben in zebrafish brain development

Humans are exposed to increasing amount of chemicals, and the concern about these substances is related to their unknown effects. In particular, recent studies focused on the controversial role of parabens, used as preservatives in food and cosmetics. They have estrogenic properties [1], which could influence the brain development in Vertebrates. In this work we examine the effect of (PrP) on brain development during early-life stages of zebrafish. PrP treatment induces an alteration in brain morphology evaluated by NeuN staining; particularly we detect an increase in nuclei positive for NeuN in PrP treated embryo respect to control. This morphological anomaly may be related to the altered lipid metabolism and development of head cartilage observed by us in embryos exposed to PrP [2]. In the present study we also investigate the expression in genes involved in neurodevelopment and synapse formation, such as Shank3a, Nrxn1 and Ngln3. Our preliminary data open to further studies to explore the toxicity associated with parabens. Since PrP acts as agonist for peroxisome proliferator–activated receptor g (PPARg) [3] that it is strongly involved in neurogenesis we hypothesize its connection in PrP action. 1 Darbre P.D., & Harvey P.W. (2008). Paraben esters: review of recent studies of endocrine toxicity, absorption, esterase and human exposure, and discussion of potential human health risks. J Appl Toxicol, 28(5), 561–578. 2 Perugini M,, Merola C., Amorena M., D’Angelo M., Cimini A., Benedetti E. (2019). Sublethal exposure to propylparaben leads to lipid metabolism impairment in zebrafish early-life stages. J Appl Toxicol, 1–11. https://doi.org/10.1002/jat.3921. 3 Hu P., Chen X., Whitener R.J., Boder E.T., Jones J.O., Porollo A., Chen J., Zhao L. (2013). Effects of parabens on adipocyte differentiation. Toxicol Sci, 131(1):56-70. doi:10.1093/toxsci/kfs262.