Prenatal lead acetate exposure induces apoptosis and changes GFAP expression during spinal cord development

Area of Science:

• Environmental toxicology
• Developmental neuroscience
• Neurobiology

Background:

• Lead is a pervasive environmental heavy metal pollutant.
• Lead exposure causes significant neurodevelopmental toxicity, affecting the central nervous system.
• Understanding lead's impact on the developing nervous system is crucial.

Purpose of the Study:

• To investigate the effects of prenatal acute lead exposure on apoptosis, glial fibrillary acidic protein (GFAP) expression, and lead deposition in embryonic spinal cords.
• To assess dose-dependent and developmental stage-specific effects of lead exposure.

Main Methods:

• Chick embryos were exposed to lead acetate (150μg or 450μg) via yolk sac injection at embryonic days 3 or 5.
• Embryos were incubated for six days post-exposure.
• Lead deposition, apoptosis (TUNEL assay), and GFAP expression were analyzed in spinal cord tissues.

Main Results:

• Lead deposition was confirmed in various spinal cord regions, including ependymal cells, dorsal/ventral horns, and white matter.
• A significant increase in apoptotic cells (TUNEL-positive) was observed in lead-exposed embryos compared to controls.
• Lead exposure led to a reduction in GFAP expression in the spinal cord.

Conclusions:

• In ovo lead exposure induces apoptosis in the developing chick spinal cord.
• Lead exposure alters GFAP expression, potentially disrupting glial cell function.
• These findings suggest prenatal lead exposure can cause neurodevelopmental impairments with potential long-term consequences.