GRIN2A polymorphisms and expression levels are associated with lead-induced neurotoxicity

Area of Science:

• Neuroscience
• Toxicology
• Genetics

Background:

• Lead is a known neurotoxin acting as an antagonist of the N-methyl-d-aspartate receptor (NMDAR).
• GRIN2A, a subunit of NMDARs, is implicated in neurotoxicity mechanisms.
• Alterations in GRIN2A expression or genetic variations may mediate lead-induced neurotoxicity.

Purpose of the Study:

• To investigate the hypothesis that GRIN2A contributes to lead-induced neurotoxicity.
• To analyze the association between GRIN2A expression and lead exposure in cellular and human populations.
• To examine the influence of GRIN2A gene single nucleotide polymorphisms (SNPs) on lead neurotoxicity risk.

Main Methods:

• HEK293 cells were used for preliminary experiments on GRIN2A expression and lead exposure.
• Serum GRIN2A levels were measured in lead-exposed individuals and controls.
• Three tag SNPs (rs2650429, rs6497540, rs9302415) in GRIN2A were genotyped in a case-control study (399 exposed, 398 controls).

Main Results:

• Lead exposure decreased GRIN2A expression in HEK293 cells (p < 0.001).
• Lead-exposed individuals exhibited lower serum GRIN2A levels (p < 0.001), with levels decreasing as blood lead increased (p < 0.001).
• The rs2650429 CT and TT genotypes were significantly associated with increased risk of lead poisoning compared to CC (aOR=1.42, 95% CI=1.01-2.00).

Conclusions:

• Reduced GRIN2A expression levels are a consequence of lead exposure.
• GRIN2A gene variants are associated with an increased risk of lead poisoning.
• Changes in GRIN2A expression and genetic variants are potential mechanisms underlying lead-induced neurotoxicity.