The crosstalk effects of polybrominated diphenyl ethers on the retinoic acid and thyroid hormone signaling pathway

Area of Science:

• Environmental Toxicology
• Neuroscience
• Endocrinology

Background:

• Polybrominated diphenyl ethers (PBDEs) are environmental contaminants with known toxicological effects on the central nervous system.
• The precise mechanisms underlying PBDE neurotoxicity remain incompletely understood.
• Retinoic acid (RA) and thyroid hormone (TH) signaling pathways are crucial for neurodevelopment and may be affected by PBDEs.

Purpose of the Study:

• To investigate the crosstalk between RA and TH signaling pathways following exposure to PBDEs.
• To elucidate the molecular mechanisms by which PBDEs, specifically BDE-47 and BDE-209, impact these critical neurodevelopmental pathways.

Main Methods:

• Utilized zebrafish larvae as a model organism for in vivo studies.
• Employed a dual reporter gene assay to assess signaling pathway activation.
• Performed docking simulations to predict ligand-receptor interactions.

Main Results:

• BDE-47 was found to disrupt retinoid transport and metabolism, alter gene expression, and activate the RA signaling pathway by binding to nuclear receptors.
• BDE-47 demonstrated more significant effects on both RA and TH pathway indicators compared to BDE-209.
• Evidence suggests BDE-47 disrupts TH signaling indirectly through its effects on the RA pathway, indicating RA signaling is affected prior to TH signaling.

Conclusions:

• PBDEs, particularly BDE-47, can interfere with neurodevelopment by disrupting the RA signaling pathway.
• The RA pathway appears to be a primary target for PBDE-induced disruption, subsequently impacting TH signaling.
• This research provides a novel perspective on PBDE neurotoxicity, highlighting the role of RA signaling in mediating TH disruption and offering insights into PBDE health effects.