Frontal –temporal regional differences in brain energy metabolism and mitochondrial function using 31P MRS in older adults

AbstractAging is a major risk for cognitive decline and transition to dementia. One well-known age-related change involves decreased brain efficiency and energy production, mediated in part by changes in mitochondrial function. Damaged or dysfunctional mitochondria have been implicated in the pathogenesis of age-related neurodegenerative conditions like Alzheimer ’s disease (AD). The aim of the current study was to investigate mitochondrial function over frontal and temporal regions in a sample of 70 cognitively normal older adults with subjective memory complaints and a first-degree family history of AD. We hypothesized cerebral mitochondrial function and energy metabolism would be greater in temporal as compared to frontal regions based on the highenergy consumption in the temporal lobes (i.e., hippocampus). To test this hypothesis, we used phosphorous (31P) magnetic resonance spectroscopy (MRS) which is a non-invasive and powerful method for investigating in vivo mitochondrial function via high energy phosphates and phospholipid metabolism ratios. We used a single voxel method (left temporal and bilateral prefrontal) to achieve optimal sensitivity. Results of separate repeated measures analyses of variance showed31P MRS ratios ofstatic energy,energy reserve,energy consumption,energy demand, andphospholipid membrane metabolism were greater in the left temporal than bilateral prefrontal voxels. Our findings that all31P MRS ratios were greater in temporal than bifrontal reg...
Source: AGE - Category: Geriatrics Source Type: research