Oops, I am a little behind but I'm still in the challenge. To catch up today I will do all three letters. Let's start with
N for
Neurofibrillary tangles.
These tangles, are due to a protein (beta-amyloid) that becomes abnormal inside the neurons rather than outside.
You see, neurons have a system of specialized filaments called microtubules that transport nutrients, organelles, and other essential materials from the cell body to the tip of the axon.
These microtubules are somewhat like a pair of rails on a
railroad, and the protein that acts as the ties that hold these rails
together and keep them parallel is called the tau protein.
In people with Alzheimer’s, the tau protein molecules disaggregate into filaments that form tangles. Thus the “rails” lose their “ties” and can no longer stay straight and properly transport the materials essential to the neuron’s survival.
The nerve endings at the very tip of the axon are the first to degenerate as a result of this lack of sustenance. As a result, communication with the following neurons in the circuit is reduced and, once the entire neuron has degenerated, cut off completely.
If you would like to know more about brain's anatomy here is the link to the
'Brain Tour'. The tour explains how the brain works and how Alzheimer's disease affects it.
O for Obesity and links between body weight and dementia risk in those over 40.
Lately there is so much in the news about harmful effect of obesity, I was pleasantly surprised to find this article:
Does midlife obesity protect against dementia? (I love comments posted below article)
This article was published a year ago and contradicts
research by Dr Rachel Whitmer published on April 29, 2005.
I want to believe that fat is good for the brain. What do you think? Please tell, I want to know.
P for Plaques
Those darn proteins not only killing neurons from inside but also from outside
by building up between nerve cells.
That build up is called plaques.
In a healthy brain, these protein fragments are broken down and
eliminated during our sleep. In Alzheimer's disease, the fragments accumulate to form
hard, insoluble plaque.
Many researchers believe that accumulations of proteins are generally only the final manifestations of diseases with earlier causes, and that amyloid plaques and neurofibrillary tangles are no exception to this rule. Some researchers even directly question the harmfulness of amyloid plaques and neurofibrillary tangles, arguing that they may in fact represent a defensive response by the brain to harmful processes that precede them, such as oxidative stress, inflammation, and dysfunctions in the cellular cycle. Some studies have shown that this protein plays a protective role against microbes.
So, go figure... all is clear as mud. There is a lot of study and research yet to be done...
So long my friends,
Evalina
