Early exposure to environmental toxins can lead to diseases much later in life. This week, Wu et al. report that primates exposed to lead as infants showed Alzheimer’s disease (AD)-like pathology years later.
From birth to 400 d of age, monkeys were exposed to lead levels that produced no obvious sign of toxicity. Although by young adulthood blood lead levels in exposed monkeys were indistinguishable from those of controls, when examined at approximately 23 years of age, the brains of lead-exposed monkeys exhibited many hallmarks of AD, including Aâ plaques and neurofibrillary tangles, as well as increased expression of Aâ precursor protein (APP) and Sp1, a transcription factor that regulates APP expression. DNA methyl transferase I activity was reduced in lead-exposed monkeys, whereas oxidative damage to DNA was increased.
These results indicate that lead exposure early in life can predispose animals to later neurodegenerative disease, possibly through alterations in DNA methylation and oxidation.
Article: "Environmental Trigger for Alzheimer’s Disease", Jinfang Wu, Md. Riyaz Basha, Brian Brock, David P. Cox, Fernando Cardozo-Pelaez, Christopher A. McPherson, Jean Harry, Deborah C. Rice, Bryan Maloney, Demao Chen, Debomoy K. Lahiri, and Nasser H. Zawia