Table 1. Cerebrospinal fluid biomarkers of BBB breakdown, vascular cells and astrocytes in mild dementia (i.e., MCI) and AD compared with cognitively normal individuals.
| Mild dementia | AD | |
|---|---|---|
| BBB breakdown | ||
| Albumin quotienta | ↑Upregulation53 | ↑Upregulation137, 140 and in AD with vascular risk factors137, 138 |
| CypAa | No existing literature | No existing literature |
| Active MMP-9a | No existing literature | No existing literature |
| Plasminogen | ↑Upregulation144 | No change143, 144 |
| Fibrinogen | ↑Upregulation141 | No existing literature |
| Pericyte markers | ||
| sPDGFRβ | ↑Upregulation53 | No existing literature |
| Endothelial markers | ||
| PDGF-BB | No existing literature | ↑Upregulation148 |
| sVCAM-1 | No change141 | ↓Downregulation151 |
| sICAM-1 | No change141 | No change151 |
| Vascular growth factors | ||
| VEGF-A | ↓Downregulation141 | ↑Upregulation,155 ↓Downregulation148 |
| VEGF-C, VEGF-D, and VEGFR1 | No existing literature | No existing literature |
| PlGF | No change141 | No existing literature |
| Tie-2 | No existing literature | No existing literature |
| Astrocyte markers | ||
| S100B | No existing literature | No change162 ↑Upregulation161 |
Abbreviations: AD, Alzheimer's disease; BBB, blood–brain barrier; CypA, cyclophilin A; MCI, mild cognitive impairment; MMP-9, matrix metalloproteinase-9; PlGF, placental growth factor; sICAM-1, soluble intercellular adhesion molecule 1; sPDGFRβ, soluble platelet-derived growth factor receptor-β; sVCAM-1, soluble vascular cell adhesion molecule 1; VEGF, vascular endothelial growth factor.
a
Upregulation in cerebrospinal fluid of cognitively normal subjects with genetic risk for AD.103