Neuropathological changes in scrapie and Alzheimer's disease are associated with increased expression of apolipoprotein E and cathepsin D in astrocytes

J. F. Diedrich, H. Minnigan, R. I. Carp, J. N. Whitaker, R. Race, W. Frey, A. T. Haase

Research output: Contribution to journalArticle

279 Scopus citations


With the rationale that the neuropathological similarities between scrapie and Alzheimer's disease reflect convergent pathological mechanisms involving altered gene expression, we set out to identify molecular events involved in both processes, using scrapie as a model to study the time course of these changes. We differentially screened a cDNA library constructed from scrapie-infected mice to identify mRNAs that increase or decrease during disease and discovered in this way two mRNAs that are increased in scrapie and Alzheimer's disease. These mRNAs were subsequently shown by sequence analysis to encode apolipoprotein E and cathepsin D (EC Using in situ hybridization and immunocytochemistry to define the cellular and anatomic pathology of altered gene expression, we found that in both diseases the increase in apolipoprotein E and cathepsin D mRNAs and proteins occurred in activated astrocytes. In scrapie, the increase in gene expression occurred soon after the amyloid-forming abnormal isoform of the prior protein has been shown to accumulate in astrocytes. In Alzheimer's disease, the increased expression of cathepsin D also occurred in association with β-amyloid. These studies reveal some of the molecular antecedents of neuropathological changes in scrapie and Alzheimer's disease and accord new prominence to the role of astrocytes in neurodegenerative conditions.

Original languageEnglish (US)
Pages (from-to)4759-4768
Number of pages10
JournalJournal of virology
Issue number9
StatePublished - Oct 15 1991


ASJC Scopus subject areas

  • Microbiology
  • Immunology
  • Insect Science
  • Virology

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