In a nation
where obesity is becoming an increasingly serious problem, it's not a surprise
that according to the American Diabetes Association, 27% of people aged 65 and
older in the US have diabetes and approximately 50% have signs of prediabetes.
A February 2015 study in Science Daily has found that diabetic individuals, in
particular those with type 2 diabetes, have been shown to have a lower level of
cognitive function and a higher risk for Alzheimer’s disease.
We have long
known about the link between diabetes and vascular dementia, the second most common
cause of dementia (the first being Alzheimer’s disease). However, type 2 diabetes in particular affects
the ability of the brain and other body tissues to use sugar and respond to
insulin. As the cerebral blood
vessels that nourish the brain are damaged by the excess blood sugar, the blood
vessels fail to nourish the brain cells effectively thus leading to increased
cell mortality and leading to the development of dementia symptoms.
The findings in
these recent studies have shown a
common pathophysiology between diabetes and Alzheimer’s
disease and that Alzheimer’s could be viewed as a new form of diabetes. This can be exhibited by the pathological process amyloidosis, in which “misfolded
proteins (amyloids) form insoluble fibril deposits, occurs in many diseases,
including Alzheimer disease (AD) and type 2 diabetes mellitus (T2D)” (Elsevier, 2015). Although
scientists are still learning about amyloid protein development and
interactions, they do know amyloid from the brain can stimulate the growth of
fibrils in the pancreas and pancreatic-derived amyloid can be found along with
brain-derived amyloid deposited in human brain senile plaques, a hallmark of
dementia. These amyloid plaques
and neurofibrillary tangles are also seen in the brain autopsies of patients
who died with diabetes.
Amyloidosis is a common finding in the pancreas of diabetics and has been attributed to the dysfunction of beta cells, which secrete insulin. Studies have shown amyloid deposits and lower beta cell mass are correlated, as the insulin resistance seen in type 2 diabetes fuels beta cells to secrete more and more insulin. This encourages amyloid deposits to form and leads to the early signs of dementia! Researchers have also identified a reduced expression of certain genes in the early stages of Alzheimer's, which happen to be the genes responsible for insulin and insulin receptor production.
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| Neurofibrillary tangles and amyloid plaques in Alzheimer cells |
The most controversial aspect of these findings is the effect of insulin therapy on dementia patients, with some saying it speeds up and others saying it slows down cognitive decline. Pathological findings have shown a combination therapy of insulin and hypoglycemic drugs had the most positive effect of the compounds studied. Nevertheless, the connection between these two diseases is still being studied and hopefully, the research being conducted will give way to new therapeutic strategies that can end this devastating disease for good. My maternal grandmother has both type 2 diabetes and late-stage Alzheimer's disease and the advancements being made in this field right now give me hope that soon enough people with similar afflictions will be living happier, healthier lives.
If you're interested, here is a great TED Talk about the link between diabetes and Alzheimer's Disease. I really enjoyed it.
Posted by Rebecca Quirie (Group C)
Great post! This was very fascinating to me, as I do not know much about diseases. I work in an Assisted Living Facility back in my hometown and seeing the progression of Alzheimer's is very scary and sad. I hope that one day there is a cure for the disease, or at least a medicine that will make it less devastating.
ReplyDeleteErika Nevins
Awesome job! This is a really interesting post. I think that it is really interesting that two diseases that don't seem to have much in common could actually be linked. And that if they are linked that there could be some kind of medicine that could help with Alzheimers and that would be an amazing discovery.
ReplyDelete-Madison Boone
I too have a maternal grandmother with diabetes and Alzheimer's disease, and your post gave me hope about future cures or medicines that could help people in her situation as well. After reading your post I can indeed see how the two diseases could be connected. Very nice job explaining how the diseases work, your post was both fascinating an informative.
ReplyDelete-Posted by Ashley Condon
There isn't a "cure" for this, you go to the gym. A huge problem sweeping America is obesity, and with that is diabetes. According to this, it'll also lead to alzheimers in the future. The idea that there's going to be a cure for this is just silly. Go to the gym and you won't be fat or have alzheimers.
ReplyDelete-Ethan
Hopefully advances in nutrition, coupled with higher public awareness of the issue of obesity will result in fewer cases of this devastating disease. I can't imagine forgetting who I was, and the fact that this study shows that this is something you could work to prevent is a huge motivator for many people to go out and exercise, which has so many benefits besides this as well. Great post!
ReplyDeleteThis is interesting I didn't know that diabetes could be a cause of Alzheimer. But it makes sense the connection because blood is distributed throughout the body. And if there are high sugar levels in that blood its bound to cause negative affects.
ReplyDelete- Jazmin Granadeno