Optical imaging reveals how Alzheimer's alters brain energy use

Researchers combined two optical imaging techniques to simultaneously measure cellular metabolism and oxygen levels in the brains of living mice, revealing distinct differences in Alzheimer's disease models compared to healthy controls. The findings link mitochondrial dysfunction with altered oxygen consumption in the disease. The study, published in Neurophotonics, used two-photon fluorescence lifetime imaging to track NAD(P)H, a metabolic indicator, and phosphorescence lifetime imaging to measure vascular oxygen pressure. Alzheimer's model mice showed a higher protein-bound NAD(P)H fraction and lower cortical oxygen levels than wild-type mice, suggesting increased oxygen consumption. The University of Virginia team notes that mitochondrial dysfunction and impaired cerebral oxygenation are both implicated in Alzheimer's but often studied separately. This combined approach allows researchers to examine how these processes interact in living tissue with minimal disruption.