Does intracrine amplification provide a unifying principle for the progression of common neurodegenerative disorders?

Many extracellular signaling proteins, such as hormones and growth factors, can act within their cells of synthe- sis or after secretion and internalization by target cells. These factors are called intracrines; aspects of their biology have been defined. The actions of these factors are mirrored in the cell-to-cell transmission of prions and prion-like proteins in common neurodegenerative disorders such as Alzheimer's disease. This suggests the possibility that intracrine-like functionality is