Chronic bisphenol A exposure induces temporal neurobehavioral transformation and augmented chromatin condensation in the periventricular gray zone of zebrafish brain

Abstract

Bisphenol A (BPA) is an industrial synthetic chemical that is extensively used for manufacturing polycarbonate plastics and epoxy resins. However, there is limited literature on BPA-induced temporal neurobehavioral transformation and oxidative stress-mediated neurodegeneration in the subtle region of the zebrafish brain. Consequently, an investigational setup was prepared to study the temporal response to duration-dependent BPA exposure on neurobehavioral, oxidative stress, and neurodegeneration in zebrafish. Zebrafish were divided into five groups: naïve, control, 7 days (BPA7D), 14 days (BPA14D), and 21 days (BPA21D). Our findings indicated that chronic waterborne exposure to BPA substantially altered the light/dark preference and bottom-dwelling behavior of zebrafish in the BPA14D, and BPA21D groups compared with naïve and control groups. Biochemical studies revealed that there was a significant downregulation in the cellular level of small-molecule antioxidants evidenced by reduced glutathione (GSH) and activity of antioxidant enzymes of glutathione biosynthesis in a duration-dependent manner after exposure to BPA. However, exposure to BPA for 7 days did not induce substantial alteration in biochemical parameters, such as GSH level, protein carbonylation, and superoxide dismutase activity, although the neurobehavioral responses expressively differed from those of the naïve and control groups. Moreover, our histopathological observation also indicated a temporal augmentation in chromatin condensation in the periventricular gray zone (PGZ) of the zebrafish brain after chronic exposure to BPA. The overall outcomes of the present study indicated that the transformed neurobehavioral phenotypes in zebrafish are a consequence of BPA-induced oxidative stress and PGZ neurodegeneration and clearly show a temporal transformation under BPA exposure.

Graphical Abstract

Keywords:

• Bisphenol A
• oxidative stress
• neurotoxicity
• periventricular gray zone
• chromatin condensation

Acknowledgements

The authors acknowledge the contribution of Siksha ‘O’ Anusandhan (Deemed to be University), Odisha, India for providing the necessary infrastructure facility and support. Dr. Das is the receiver of UGC start-up and ICMR extramural (multi-institutional) research grants. The authors would like to thank Enago (Crimson Interactive Inc., USA) for English language editing and proofreading. The authors also recognize the contribution of Dr. Ritendra Mishra, Mumbai, India for giving critical inputs in proofreading of the manuscript.

Author contributions

SKD: Conceptualization, Funding acquisition, Writing-Original draft

PKS and LKP: Data curation, Investigation, Formal analysis

Disclosure statement

No potential conflict of interest was reported by the author(s).

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.