11 Understanding Plaques
Plaques are formed when pieces of protein known as beta-amyloid join together. Beta-amyloid is located in larger proteins normally found within the fatty membrane around the nerve cells.
Beta-amyloid is a sticky in a chemical sense and slowly builds up in the plaques.
Groups of beta-amyloids of a few pieces or more could be more damaging than the actual plaques. These clumps could inhibit signalling between cells and the synapses. They could also be activating immune system cells which are triggering inflammation and devouring disabled cells.
12 Understanding tangles
Tangles are the cause of destruction within essential cell transport systems made up of proteins. The electron microscope images illustrates a cell with healthy areas along with zones where tangles are beginning to form.
In the healthy area:
The transportation system is organized in parallel strands much like railway tracks. Cell parts, food molecules and other essential materials move along these “tracks”
Proteins called tau help the track to remain straight
In regions where the tangles are formed:
Tau proteins collapse into tangles – the twisted strands
The tracks cannot stay straight, instead the disintegrate and fall apart
Nutrients and other important supplies cannot move between the cells so they eventually die.
13 How it Progresses through the brain
Tangles and plaques (indicated by the blue areas) are typically spread throughout the cortex in a fairly predictable pattern as the progression of Alzheimer’s sets in.
Progression rates vary greatly with some people living an average of just eight years, while others can live for as much as 20 years. The progression rates depend on various factors, including the age when the person is diagnosed and also if they have other existing health problems.
Early Alzheimer’s – changes could occur anywhere up to 20 years prior to diagnosis.
Mild Alzheimer’s – in general lasts between two to 10 years.
Severe Alzheimer’s – can last between one to five years.
14 Alzheimer’s in its Earliest Stages
In the earliest Alzheimer’s stages, prior to symptoms being detected with current testing, tangles and plaques start to form in areas of the brain associated with:
Memory and learning
Planning and thinking
15 Mild Alzheimer’s
In the mild to moderate period, the areas of the brain essential for thinking, planning and memory develop more tangles and plaques than were evident in the early stages. Due to this, individuals can develop problems with thinking and memory that are severe enough to create issues with their normal social and work life. The can become confused and have issues with handling money, collecting their thoughts and expressing themselves. Many people that have Alzheimer’s are initially diagnosed in this stage.
Tangles and plaques can also spread into areas associated with:
Speech and interpreting speech
Your sense of spatial awareness
As the disease progresses, people can experience a change in behavior and personality while they can also have issues recognizing family members or friends.
16 Alzheimer’s in severe stages
Once Alzheimer’s is advanced the majority of the cortex is damaged significantly. The brain size shrinks a great deal following widespread cell death. People with Alzheimer’s lose the ability to recognize their family and friends, the ability to communicate and to take care of themselves.
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