Alzheimer’s disease is a protein misfolding disease caused by the accumulation of abnormally folded amyloid beta protein into amyloid plaques, and tau protein into neurofibrillary tangles in the brain.
These amyloid beta plaques cause programmed neuronal cell death. As these neurons die, it causes disruptions in the supply of blood to regions of the brain, affecting levels of oxygen, glucose and nutrients. Studies have shown Cerebral Blood Flow (CBF) to be on average 20% lower in people with Alzheimer’s compared to those without a neurodegenerative disease.
Alzheimer’s also affects the distribution of different neurotrophic factors such as the brain-derived neurotrophic factor (BDNF). BDNF acts on certain neurons of the central and peripheral nervous system, supporting survival of existing neurons, and encouraging growth and differentiation of new neurons and synapses. BDNF is essential to normal brain function, and reduced levels can lead to reduced cognitive abilities and depression.