Early Lead Exposure May Lead to Alzheimer’s Later in Life
Measurements taken to reduce lead exposure may already be helping to prevent children today from having Alzheimer’s later in life. A study that took place over a 23 year time span showed that monkeys who drank a formula rich in lead while they were infants later developed the tangles of tau, a key brain protein linked to Alzheimer’s. Although more research needs to be performed before there is conclusive proof of the connection, lead has already been removed from paint, water, car emissions and soil that is known to cause serious health conditions involving the heart, kidneys, intestines and nervous system. Even small doses can cause serious harm. In spite of the precautions being taken, 1 in 38 children in the US have harmful levels of lead in their systems.
According to an article in Science Now, a research team led by toxicologist Nasser Zawia has been vigorously pursuing the hypothesis that early lead exposure has a connection to the development of the disease. An early study showed that plaques made up of insoluble globs of the protein β-amyloid marred the brains of five macaques which had consumed a formula that was enriched with lead as infants. A comparison of brain tissue from those macaques was made to four of similar age which had not consumed the lead formula. The connection is the amyloid plaques which closely resemble those in the brains of adults who have Alzheimer’s disease and are believed to have contributed to the dementia.
The team of researchers has continued their studies with brain samples from the original five macaques to eliminate the potential of a different structural change that has a stronger link to Alzheimer’s. An examination of frontal cortex tissues has shown them to have three times more of the irregular tau protein in the brain cells when compared to those of the normal monkeys. Even further, the genetic instructions responsible for assembly of tau proteins had been altered, suggesting that early exposure to lead had epigenetically reprogrammed the DNA.