Correlation between each task of the Mini-Mental State Examination and regional glucose hypometabolism in at-rest Alzheimer's disease patients

Locus Coeruleus and Noradrenergic Pharmacology in Neurodegenerative Disease

Adrenoceptors (ARs) throughout the brain are stimulated by noradrenaline originating mostly from neurons of the locus coeruleus, a brainstem nucleus that is ostensibly the earliest to show detectable pathology in neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. The α1-AR, α2-AR, and β-AR subtypes expressed in target brain regions and on a range of cell populations define the physiological responses to noradrenaline, which includes activation of cognitive function in addition to modulation of neurometabolism, cerebral blood flow, and neuroinflammation. As these heterocellular functions are critical for maintaining brain homeostasis and neuronal health, combating the loss of noradrenergic tone from locus coeruleus degeneration may therefore be an effective treatment for both cognitive symptoms and disease modification in neurodegenerative indications. Two pharmacologic approaches are receiving attention in recent clinical studies: preserving noradrenaline levels (e.g., via reuptake inhibition) and direct activation of target adrenoceptors. Here, we review the expression and role of adrenoceptors in the brain, the preclinical studies which demonstrate that adrenergic stimulation can support cognitive function and cerebral health by reversing the effects of noradrenaline depletion, and the human data provided by pharmacoepidemiologic analyses and clinical trials which together identify adrenoceptors as promising targets for the treatment of neurodegenerative disease.

Association between Regional Cerebral Blood Flow and Mini-Mental State Examination Score in Patients with Alzheimer's Disease

BACKGROUND

In patients with Alzheimer's disease (AD), cerebral blood flow (CBF) is decreased from the early stages. CBF in AD is currently estimated from Z-scores using statistical analysis. However, the Z-score is not considered the impaired area ratio.

METHODS

In the present study, a novel indicator, ΣzS, associated with brain surface area and Zscores, is defined and the association with regional CBF has been estimated using Mini-Mental State Examination (MMSE) scores, which indicate the severity of cognitive impairment in patients with AD.

RESULTS

A negative correlation was detected between ΣzS in the posterior cingulate gyrus and the subset numbers 1, 2, and 5 of the total MMSE scores. Furthermore, a negative correlation was detected between the total MMSE score and ΣzS in Brodmann area 30, which is a subdivided area of the brain.

CONCLUSION

These results suggest that ΣzS may be a useful indicator of CBF metabolism, and thus may improve the current understanding of cognitive function in patients with AD.

Development of PET radiopharmaceuticals and their clinical applications at the Positron Medical Center

The Positron Medical Center has developed a large number of radiopharmaceuticals and 36 radiopharmaceuticals have been approved for clinical use for studying aging and geriatric diseases, especially brain functions. Positron emission tomography (PET) has been used to provide a highly advanced PET-based diagnosis. The current status of the development of radiopharmaceuticals, and representative clinical and methodological results are reviewed.