Photonic Probing of Structural Alteration in DNA Molecular Spatial Mass Density Fluctuations in the Nuclei of Human Brain Cells in Progressive Alzheimer's disease

Alzheimer's disease (AD) is one of the most common neurodegenerative disorders worldwide and a leading cause of death among the elderly. It is characterized by the accumulation of amyloid protein plaques between nerve cells in the brain. In the early stages of AD, a loss of cognitive function is one of the most noticeable symptoms. It is believed that Alzheimer's may begin decades before symptoms start. Although a person may not show symptoms during this period, the damage occurs in the brain as tau proteins tangle and amyloid plaques build up. This may influence the brain cells/tissue structures at the nanoscale level which the present histopathological procedures can’t detect. Molecular specific photonics localization technique, the inverse participation ratio (IPR), is a promising technique to study the nanoscale structural alterations due to AD in brain cells/tissues using molecular-specific confocal imaging. We quantify nanoscale spatial structural alterations in DNA molecular spatial mass densities in brain cell nuclei. The results show an increase in the degree of spatial structural disorder in DNA modification with AD progression. An increase in spatial disorder in DNA molecular mass density may suggest DNA damage or spatial rearrangement caused by the deposition of amyloid beta protein plaques and neurofibrillary tangles inside and between the neurons.