Newborns Share a Biomarker with Alzheimer’s Patients

An intriguing biological similarity has been discovered between newborns and individuals with Alzheimer’s disease: both have elevated levels of a notable Alzheimer’s biomarker, according to a study conducted by researchers at the University of Gothenburg and published in Brain Communications.

Fernando Gonzalez-Ortiz, the first author, along with senior author Professor Kaj Blennow, noted that both groups exhibit heightened blood levels of a protein called phosphorylated tau, specifically p-tau217. This protein is primarily used in diagnosing Alzheimer’s, where increased levels are thought to be linked to the formation of amyloid plaques. Interestingly, newborns lack this pathological condition, suggesting that their elevated p-tau217 may reflect an entirely different, healthy process.

A wide-ranging international study included over 400 participants from Sweden, Spain, and Australia, analyzing blood samples from healthy newborns, premature infants, young adults, older adults, and Alzheimer’s patients. The findings showed that newborns displayed the highest levels of p-tau217, even surpassing those of Alzheimer’s patients. Particularly, premature infants had significantly increased levels, which gradually declined over the first months of life, reaching adult levels eventually.

First Measurement of p-tau217 in Newborns

Previous studies, mainly using animal models, had suggested phosphorylated tau plays a role in early brain development. This study marks the first direct measurements of p-tau217 in human newborns, paving the way for a better understanding of its function in development.

What’s particularly interesting is the dual role of p-tau217. In the context of Alzheimer’s, it is associated with the aggregation into harmful tangles that damage brain cells, leading to cognitive decline. Yet, in newborns, this increase appears to facilitate healthy brain development, aiding in neuron growth and connection formation.

The study also discovered a link between p-tau217 levels and the prematurity of infants—suggesting that the earlier the birth, the higher the levels, which seem to support rapid brain growth in challenging conditions.

Implications for Future Treatments

What’s compelling about these results is the notion that our brains may have inherent protective mechanisms, allowing newborns to thrive with high levels of p-tau217 without the adverse effects associated with Alzheimer’s. Gonzalez-Ortiz highlighted the importance of understanding this natural protection: “If we figure out how the newborn brain manages this, we could potentially apply those insights to develop treatments for Alzheimer’s.”

While elevated p-tau217 is a warning signal in older individuals, it may play a crucial role in building the brains of newborns. This underscores just how differently the same molecule can function across different life stages.

With recent FDA approval for diagnosing Alzheimer’s, plasma p-tau217 has become increasingly pivotal in clinical settings. The authors emphasize the need to further explore the mechanisms behind p-tau217 increases, especially considering implications for clinical, epidemiological research, and drug development. This study suggests that amyloid plaques may not be the primary cause of elevated p-tau217 levels.

In conclusion, the findings not only shed light on the developmental significance of tau proteins but also open avenues for potential therapeutic strategies against Alzheimer’s in the future.