An NIA-backed study, recently published in the Annals of Neurology, introduces a brain cell communication protein that may serve as an early indicator for the onset of mild cognitive impairment (MCI), a precursor to conditions like Alzheimer’s disease. MCI designates a state of cognitive function where individuals, typically older adults, experience memory or thinking challenges that exceed the norm for their age bracket, yet the symptoms do not severely hamper their everyday activities. Often, in the context of Alzheimer’s disease, MCI represents the initial phase of the illness, marking the advent of more pronounced cognitive deterioration. This phase is characterized by deleterious brain alterations instigated by Alzheimer’s, which can stealthily take root up to a decade or more before the emergence of recognizable symptoms like memory lapses.
In the race to identify MCI early, researchers are probing biomarkers — measurable indicators of a disease’s presence observed in brain scans, cerebrospinal fluid, or blood samples. Predominantly, Alzheimer’s biomarker investigations have concentrated on detecting beta-amyloid and tau proteins, the defining pathologies of the disease.
A collaborative research initiative spearheaded by Johns Hopkins University is delving into the potential of neuronal pentraxin 2 (NPTX2) as an early biomarker for mild cognitive impairment (MCI). NPTX2 is a protein that facilitates synaptic communication—the crucial exchange of information between nerve cells—which underpins cognitive function. Given the established correlation between synaptic loss and Alzheimer’s-related cognitive decline, and the consequent observed decrease in NPTX2 levels, this protein emerges as a promising predictor of cognitive impairment.
The researchers set their sights on discerning whether fluctuations in NPTX2 could presage the onset of MCI, even before cognitive symptoms manifest. They directed their research towards participants of the Johns Hopkins’ Biomarkers for Older Controls at Risk for Dementia (BIOCARD) study—a group initially free from dementia, who underwent extensive yearly clinical and cognitive monitoring over an impressive 16-year average. By juxtaposing these longitudinal cognitive data against the levels of NPTX2 in cerebrospinal fluid, which cushions the brain and spinal cord, the scientists aimed to uncover a predictive relationship.
Subsequent scrutiny hinted at NPTX2’s unique predictive capacity for MCI, functioning independently of the established Alzheimer’s markers, beta-amyloid and tau. Interestingly, predictions seem to sharpen when NPTX2 levels are considered alongside these conventional biomarkers. As such, these findings lend weight to the argument for further exploratory studies on NPTX2’s implications in the intricate neurobiology of dementia, including Alzheimer’s disease specifically. Forthcoming research endeavors should prioritize not only a larger scale but also a more varied demographic makeup to ensure the findings’ applicability across populations.