Denied Access of Ions and Molecules to Axons in the Development of Alzheimer's Disease

Gels of Amyloid Fibers

“…We reported that earlier protein gels deposited by the axons attenuate the propagation of action potential [10]. The similar ion conductance across tubes filled with GAF or buffer solution shown in Figure 4 suggests that the ion movement is not attenuated by the presence of gels if an electric field is present.…”

“…One major difference between a dense core and diffused plaque is the limited transportation of molecules through the former (Figure 6). We recently reported that protein gels can attenuate the propagation of action potential [10] and introduced the denied access model that the neurite regions surrounded by amyloid gel plaques are denied from accessing to nutrient and signaling molecules, as well as to the drainage pathways for metabolic wastes. Our work suggests that an electric field can drive ions through the amyloid fiber gel.…”

“…The neurite regions surrounded by amyloid gel plaques are denied from accessing to nutrient and signaling molecules as well as to the drainage pathways for metabolic wastes. This denied access leads to the inhibition of the action potential propagation and eventually the degeneration of the disused neurites [10,31].…”

“…Since movement of molecules and ions is critical for cellular processes, such impact by GAF to tissue permeability can thus explain the cell death and tissue damage as seen in AD brain and systematic amyloidosis. Recently, we found that fibrin gels formed around sciatic nerves fibers attenuated the propagation of compound action potential [10]. It is unclear whether such attenuation is a result of restricted movement of ions, such as Na + and K + , or molecules, such as oxygen, glucose and insulin.…”