High expression on Kunitz-type protease inhibitor-containing substances in the cerebral vessels of patients with Down syndrome

Topic: Brain proteins, microglia and lab models

Down syndrome (DS) brains, from 19 gestational weeks to 50 years of age were studied by immunohistochemical methods with a polyclonal antibody against synthetic peptide comprising part of the Kunitz-type protease inhibitor (KPI) domain of Alzheimer disease amyloid precursor protein (APP), residues 301 to 323 of APP 770. In DS, positive KPI immunoreactivity was observed in early infancy and from child to adulthood on the tunica media of the arteries in the leptomeninges, cerebral cortex and white matter, but negative or little in controls. In DS with Alzheimer type dementia, KPI immunoreactivity in the arteries was reduced, but a gross granular reactivity was noted in neurons and glial cells. The high expression of KPI in DS vessels may be one of the predisposing factors to vascular diseases and amyloid deposition associated with DS.

Key findings

• The high expression of KPI in DS vessels may be one of the predisposing factors to vascular diseases and amyloid deposition associated with DS.

Why it matters

In brain tissue from people with Down syndrome, a Kunitz-type protease inhibitor part of the amyloid precursor protein was found at high levels in cerebral blood vessels from infancy onward, and this was reduced in those with Alzheimer-type dementia. The authors suggest this high vessel expression may be one factor predisposing to vascular disease and amyloid deposition in Down syndrome.

Study details

• Evidence strengthLow

Read the original

• DOI: 10.1620/tjem.174.181
• PubMed: 7761983
• Original source →
• Free full text: The Tohoku Journal of Experimental Medicine →

Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).

@article{suzuki1994-7761983,
  author  = {Suzuki, A. and Takashima, S. and Mizuguchi, M. and Kato, M. and Kunishita, T. and Tabira, T.},
  title   = {{High expression on Kunitz-type protease inhibitor-containing substances in the cerebral vessels of patients with Down syndrome}},
  journal = {The Tohoku journal of experimental medicine},
  year    = {1994},
  doi     = {10.1620/tjem.174.181},
  pmid    = {7761983},
  url     = {https://doi.org/10.1620/tjem.174.181}
}

Studies this one cites

Referenced by this study and also in the alzhub library, so you can read them here.

• Alzheimer's disease in Down's syndrome: clinicopathologic studies Neurology · 1985-07-01 · usefulness score 61/100 · Getting a diagnosis
• The precursor of Alzheimer's disease amyloid A4 protein resembles a cell-surface receptor Nature · 1987-02-01 · usefulness score 58/100 · Disease mechanisms
• Mapping of the gene encoding the beta-amyloid precursor protein and its relationship to the Down syndrome region of chromosome 21 Proceedings of the National Academy of Sciences of the United States of America · 1988-11-01 · usefulness score 44/100 · Down syndrome and Alzheimer's
• Dendrites, dementia and the Down syndrome Brain & development · 1989-01-01 · usefulness score 40/100 · Down syndrome and Alzheimer's

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