Converging molecular pathways in human neural development and degeneration.

Area of Science:

• Neuroscience
• Developmental Biology
• Pathology

Background:

• Animal studies indicate tau phosphorylation destabilizes axons, aiding synaptic plasticity in developing brains.
• In adult humans, tau phosphorylation is a hallmark of Alzheimer's disease.
• The role of tau phosphorylation in early human brain development remains unclear.

Purpose of the Study:

• To investigate the levels of phosphorylated tau in the cerebrospinal fluid of newborn infants.
• To determine how phosphorylated tau levels change during early human development.
• To re-evaluate the significance of tau phosphorylation in Alzheimer's disease.

Main Methods:

• Analysis of cerebrospinal fluid (CSF) samples from newborn infants.
• Quantification of phosphorylated tau protein levels using biochemical assays.
• Longitudinal assessment of tau phosphorylation over the first years of life.

Main Results:

• Newborn infants exhibit exceptionally high levels of phosphorylated tau in their CSF.
• These elevated phosphorylated tau levels significantly decrease during the first few years of life.
• A distinct developmental trajectory for tau phosphorylation in humans was observed.

Conclusions:

• High phosphorylated tau in newborns suggests a crucial physiological role in early brain development.
• The decrease in phosphorylated tau post-birth may reflect the maturation of neuronal structures.
• Tau phosphorylation in Alzheimer's disease could represent a physiological response to synaptotoxicity, rather than solely a pathological process.