Researchers Release Compelling Evidence of Alzheimer’s Link to Early Lead Exposure

Law Firm Newswire



Bloomfield Hills, MI (Law Firm Newswire) January 15, 2014 – A new study has found that infant primates who were fed lead-rich formula later develop key signs of disease.

Scientists have known for some time that there are three primary risk factors for Alzheimer’s disease: advanced age, family history and genetic make-up. However, the results of a long-term study released in December has now provided solid evidence that early exposure to lead is also a key factor in the development of Alzheimer’s-induced dementia.

A team of researchers from the University of Rhode Island, Kingston (URI) conducted a 23-year study that found that macaque monkeys who were fed a lead-rich formula as infants later developed a protein called tau, which has a known association with the onset of Alzheimer’s disease. Indeed, the monkeys used in the trials were found to have three times as much irregular tau protein in their brains than infant monkeys who consumed a normal formula did.

Another telling finding showed that the genetic instructions that assemble the tau protein in the monkeys were altered after the infants outgrew the lead-tainted formula. That fact suggests that lead exposure during infancy epigenetically reprogrammed the primates‘ DNA.

An earlier, supporting study also determined that baby monkeys fed formula enriched with lead later developed brains marred by the presence of amyloid plaques very similar to the ones present in the brains of adults with Alzheimer’s disease.

The researchers’ new findings are significant because it has long been known that, even in small doses, consumption of lead can cause damage to body organs, intestines and the nervous system. Children, whose brains are in an early and normally rapid stage of development, are particularly susceptible to the deleterious effects of lead consumption. Researchers have calculated that one in 38 children in the United States has harmful levels of lead within their body.

Some neuroscientists are particularly piqued by the URI findings because the brain physiologies of macaque monkeys and humans are significantly similar. These similarities have prompted at least one specialist to call upon dementia researchers to take the results seriously.

“This study adds another important piece to this link between early-life lead exposure and Alzheimer’s-like pathology,” said Marc Weisskopf, a neuroscientist at the Harvard School of Public Health in Boston.

Up until the results of the URI team’s study were released, the link between lead consumption during childhood and the development of Alzheimer’s disease in old age was tenuous at best. Scientists continue to caution that more studies to confirm the correlation will have to be conducted. Still, the team’s findings, which were published in the December issue of NeuroToxicology, have left researchers hopeful.

“This is very strong evidence that early [lead] exposure can determine what happens in old age,” said Nasser Zawia, lead toxicologist of the URI research team.