Table 2.
Features of the Cerebral Microvasculature and BBB in Ageing and Neurodegenerative Dementia
| Cellular Feature | Morphological changes | Biochemical markers |
|---|---|---|
| Cerebral endothelium | Loss of cytoplasm and endoplasmic reticulum. Increased pinocytosis. | ↓ glucose transporter-type 1, Na+/K+ ATPase, CD31, CD34 |
| Changes in cytoplasm (oxidative and endoplasmic reticulum stresses | ↑ glucose-6-phosphatase; proteases (endothelin converting enzyme-1) | |
| Endothelial membranes/ microvascular endfeet | ↓ Alkaline Phosphatase, γ-GT, Cholinesterases | |
| Decreased mitochondria | ↓ Carnitine aceytltransferase | |
| Loss of tight junctions | ||
| Vascular basement membranes | Thickening of the extracellular matrix, collagen fibers | ↑ Collagens, perlecans, fibrinogen, matrix metalloproteinases |
| Perivascular cells | Increased astrocytic feet | ↑ GFAP reactivity |
| Increased pericytes | ↑ CD68, macrophage markers | |
| Arteries/arterioles | Loss of vascular smooth muscle cells; increased microthrombi | ↓ α-smooth muscle actin; accumulation of amyloid β |
| Cerebral microvessels | Changes in cerebral endothelium and perivascular cellular elements | ↑ Inflammatory mediators and cytokines |
Results derived from previously published reviews and studies15, 29, 34–36 and unpublished data (Kalaria et al). Arrow indicates decrease or increase.
Abbreviations: AlkP, alkaline phosphatase; CD, clusters of differentiation markers; GFAP, glial fibrillary acid protein; GGT, γ-glutamyl transpeptidase.