Neurovascular coupling and energy substrate delivery in Alzheimer's disease.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing mechanistic concepts without systematic search or primary human data
PubMed 42276622 · doi:10.1016/bs.irn.2026.05.001
What was done
This paper is a narrative review examining the role of the neurovascular unit (NVU), neurovascular coupling (NVC), and cerebral metabolic substrate delivery (primarily glucose and oxygen) in the pathophysiology and progression of Alzheimer's disease.
What was found
The abstract reports no primary experimental data or quantitative study metrics beyond the baseline physiological note that the brain consumes over 20% of the body's energy while accounting for approximately 2% of body weight. It qualitatively describes how NVU breakdown—including endothelial dysfunction, pericyte loss, blood-brain barrier disruption, down-regulation of GLUT1 transporters, lactate abnormalities, and mitochondrial dysfunction—drives early cerebral hypometabolism before significant amyloid-β and tau accumulation occur.
Why it matters
It reinforces the framework that vascular and metabolic deficits are early upstream drivers rather than late secondary consequences of Alzheimer's disease, highlighting vascular restoration and metabolic support as key targets for early intervention.
Limits
As a narrative review, it does not use a systematic review methodology, risk of bias assessment, or quantitative meta-analysis. The abstract provides no specific clinical sample sizes, effect sizes, or direct clinical trial outcomes.
Cited by
- partial The human brain accounts for 30% of total energy utilization in the human body.