Dementia is an overall term for a series of diseases and conditions involving the brain. It is characterized by a decline in memory, language, problem solving and other thinking skills that affect a person's ability to perform everyday activities. It is a very scary condition since the function of the brain is what makes each of us who we are. It is notable that some types of dementia involve the misfolding of specific proteins found in the normal brain.
As an individual, you are the result of the myriad of proteins that are produced by the DNA (genes) that you received from your mother and father. Proteins are chains of a few, to hundreds, of smaller molecules called amino acids. It is the number, kind and specific sequence of the 20 different amino acids found in proteins that is determined by the DNA.
This sequence then leads to a folding of the chain to produce a specific and unique shape for the molecule. It is this shape that gives each protein its ability to carry out a specific function in the body. These functions include such things as the source of building materials for all the different cells of the body as well as the source of hormones, enzymes, antibodies, etc. for cell and body functions.
Alzheimer's is a disease that involves the misfolding of two brain proteins. It is the most common dementia among older adults and today it affects some 5.5 million Americans and is increasing. It is the underlying cause of some 500,000 deaths each year. The causes probably include a combination of genetic, environmental and lifestyle factors. When someone develops Alzheimer's, there appears to be an issue with two naturally occurring brain proteins identified as amyloid and tau.
For reasons not yet fully understood, the misfolding of amyloid produces plaques that collect outside nerve cells (neurons) disrupting their activity and eventually leading to their death. The tau protein produces tangled strands inside neurons. This disrupts the flow of signals within the neuron and causes the neuron to wither and die.
Researchers are trying to understand and track the cascade of events in the brain that leads to Alzheimer's. It is hoped that doctors will soon be able to identify those most at risk based on their genetics, conduct imaging tests to determine the onset, and then start the most effective therapies to either slow or halt further progress of the disease.
Larrie Stone is a retired Dana College science professor.