Alzheimer’s disease and vascular risk factors with a focus on cerebral small vessel diseases

Akihiro Shindo¹⁾²⁾, Hidekazu Tomimoto²⁾

¹⁾Department of Dementia Prevention and Therapeutics, Mie University Graduate School of Medicine
²⁾Department of Neurology, Mie University Graduate School of Medicine

Alzheimer’s disease (AD) is the most common form of dementia and clinically characterized by progressive decline of cognitive function.　The key hallmarks for the diagnosis of Alzheimer’s disease are accumulation of amyloid-β (Aβ) peptide into extracellular plaques and tau associated neurofibrillary tangles.　On the other hand, vascular dementia (VaD) is the second cause of dementia, and there is a continuous spectrum of AD and VaD.　Cerebral small vessel disease (SVD) is one of the pathological conditions of cerebral small vessels with various sizes.　The two main types of SVD are hypertensive SVD (type 1 SVD) and cerebral amyloid angiopathy (type 2 SVD).　Both these two types can affect the AD pathology.　There has been complicated mechanism in the development of Alzheimer’s disease.　Several clearance mechanisms in the brain have been assumed for Aβ excretion and SVD can interfere this clearance system.　Understanding the pathological condition of SVD might be pivotal to explore for the pathogenesis of Alzheimer’s disease.

Key words: hypertension, cerebral amyloid angiopathy, astrocyte, aquaporin 4, perivascular drainage pathway, glymphatic pathway

Address correspondence to Dr. Akihiro Shindo, Department of Dementia Prevention and Therapeutics, Mie University Graduate School of Medicine（2-174 Edobashi, Tsu, Mie 514-8507, Japan）