Persistent Metabolic Changes Are Induced by 24 h Low-Dose Lead (Pb) Exposure in Zebrafish Embryos

Area of Science:

• Environmental toxicology
• Developmental biology
• Metabolomics

Background:

• Lead (Pb) is a toxic heavy metal with known adverse effects.
• Limited research exists on the mechanistic impact of lead on development.
• Zebrafish embryos (Danio rerio) serve as a valuable model for studying chemical exposure effects.

Purpose of the Study:

• To investigate the impact of varying lead concentrations on the metabolome of developing zebrafish embryos.
• To identify potential biomarkers of lead exposure and understand dose-dependent effects.
• To elucidate the mechanistic pathways affected by lead during early development.

Main Methods:

• Zebrafish embryos were exposed to 5, 15, 150, and 1500 ppb lead for 24 hours post-fertilization.
• Untargeted metabolomics and multivariate analysis were employed to assess metabolic profiles.
• Inductively coupled plasma mass spectrometry (ICP-MS) was used to quantify lead accumulation.

Main Results:

• Lead exposure differentially altered the embryonic metabolome across various concentrations.
• Significant dysregulation was observed in biopterin, purine, alanine, and aspartate metabolism.
• Lead accumulation was confirmed in embryos, with observed decreases in oxidation-reduction ratios suggesting a hormetic effect at lower doses.

Conclusions:

• Lead exposure induces persistent, global changes in the developing zebrafish metabolome.
• Metabolomic profiles can serve as biomarkers for lead exposure, revealing dose-dependent relationships.
• Lead exposure impacts cellular energy metabolism and highlights aberrant processes in early development.