A not-so-recent discovery could relate two of the most known diseases, diabetes and Alzheimer’s, to make their cure a much more reachable goal.
Diabetes, especially Type 2, which is the one we’re going to talk about today, is a disease caused mostly by lifestyle, like eating high-energy foods, lots of sugar, fat, or little exercising. Normally, when there are high sugar levels in blood, the pancreas releases insulin to make the liver process all this glucose to turn it into glycogen, which the body can then store. But when the levels are repeatedly high, and therefore the pancreas releases a lot of insulin, cells start to resist to its effects, so they no longer convert glucose. This causes a lot of metabolic problems and memory loss issues.
Alzheimer’s a completely different story. It is a form of dementia normally caused by age, and its effects range from memory loss to irritability and in the last and worse stages can lead to loss of bodily functions and ultimately, death.
A few years ago, these diseases were observed apart, seemingly different from each other in most ways. But through the years, more and more proofs have been found that support this very interesting theory that states that Alzheimer’s is actually late stage diabetes. This could mean that the memory loss caused by diabetes is actually an early-stage symptom of Alzheimer’s.
One of these proofs is epidemiological. It has been found that people with Type 2 diabetes have a bigger chance of having Alzheimer’s than those who don’t suffer it. This lead scientists to search for a common trait in the diseases and it was found by researcher in Brown University, who discovered that for those with Alzheimer, the part of the brain that manages memories (the hippocampus), was resistant to insulin, in a similar way in which the liver is resistant to insulin in people with diabetes.
But a question remained: how does being insensitive to insulin cause dementia? The answer is quite complicated. Supposedly, people with diabetes have their brains full of an insoluble protein called beta-amyloid, which is produced by smaller, soluble versions of the protein called oligomers. This substance is very abundant in the brain, and causes receptors to bind with it instead of with insulin.
Scientists did an experiment with rats to back up this theory, and here’s how it went:
There were 2 groups of rats, a healthy group, and a diabetes group. The test was to see how much time the rats froze by seeing a chamber that gave shocks. The healthy rats froze for more time than the diabetic ones. But when a sample of antibodies, engineered to cancel the actions of the oligomers was injected into the unhealthy rats, they froze the same amount of time than the other group.
So ultimately, the cure would be to inject people with high levels of oligomers in the brain with these amino acids, so the brain would continue reacting to insulin. However, these substances and their effects on the brain have been studied for years now, and there hasn’t been any real change. Also, for these amino acids to work, they have to be injected directly into the hippocampus, which can be a bit complicated in humans. And although a good percentage of people suffering from Alzheimer’s have diabetes, not all of them have, so there is still some work to do in the other branches of this disease.
However, if this theory was proven to be completely true, it could have major implications. Both diabetes and Alzheimer’s are very common diseases, and the number of affected people is predicted to increase very rapidly in the next few years.
Right now, there is no cure for Alzheimer’s, but there are many treatments for Type 2 diabetes, and our society is becoming more health conscious by the minute, so if the former disease could be stopped, Alzheimer’s could be potentially beaten too, given enough time.