(Inside Science) -- I have a friend whose grandmother died of Alzheimer’s disease. I met her once when I was a child, in a little room of a large nursing home. I never forgot my friend’s expression -- or that of her mother, who was caring for her. One in three people in the U.S. over the age of 65 will suffer from Alzheimer’s disease. It touches so many of us and the experience is horrible.
At first you start to lose your memory. Then your general cognitive ability starts to drop. By the end of the disease your behavior and personality change, and you may suffer from hallucinations and seizures. From early on, you need caring for, and this is devastating for the caregivers – watching someone they love have their personality stripped away from them.
But what is happening in the brain? First, the brain tissue degenerates, starting in the hippocampus and frontal lobes, and then spreading across the whole cortex and finally into the lower brain structures. And this is what causes the changes in behavior.
If you zoom in to the microscopic level, you can see amyloid-beta proteins coagulating between cells to form sticky plaques, and tangles of tau proteins appear within the neurons. But neither are completely responsible for the disease. And likewise, we know of many genes that contribute to making these plaques and tangles, but no gene can make you certain of contracting the disease.
The most important question is, will we ever be able to cure it? Well, we’ve been trying, but it’s not been going well.
We have yet to produce a single drug that can combat the disease. One of the biggest problems is that we don’t really know how you catch Alzheimer’s disease. There’s certainly a genetic component, some forms of it, but infection may play a role, as well as the action of the glial and microglial cells that live alongside the neurons in the brain. And why does it occur overwhelmingly in the old, when in fact, we might actually contract Alzheimer’s early in life -- but while our brains are young and strong, we can live with it for some time.
So now the thinking is, instead of trying to fight the disease, why don’t we focus on beefing up the brain cells so they can live alongside the disease?
So, that is what a lot of research is doing now -- making drugs that keep neurons healthy and synapses growing, even as the disease progresses, and on top of that, finding new ways of diagnosing Alzheimer’s early so we can start bolstering the brain as soon as possible.
One thing we can all do is combat the disease by adapting our lifestyle. Exercise, diet and mental stimulation are all potential ways to help to keep the brain robust, so it can hold off the disease for longer.
We will unravel the riddle that causes Alzheimer’s -- there are many exciting theories -- soluble amyloid, the glymphatic system, microglial inflammation to name but a few -- and when we finally know the cause, the cure cannot be far behind.