So pretty much everyone has heard of Type-II diabetes and its connection to obesity. The hallmark of Type-II diabetes is insulin resistance. Basically your body is making so much insulin in response to the glucose in your body that you build up a resistance to it. Well recent studies have now begun to show a connection between insulin and Alzheimer’s. Now normally when people thing about insulin you think about what it does in the blood, but insulin is very important for signaling in the brain. Insulin and IGF-1 (Insulin-like Growth Factor) are important in brain energy homeostasis, neuronal survival, and learning/memory. With less insulin in the brain, more neurons die and you see the memory loss associated with Alzheimers. One of the ways this happens has to do with Tau-proteins. Tau proteins are basically structural proteins that help support your neurons. When these proteins are phosphorylated, they begin to unfold. Insulin normally down-regulates their phosphorylation. With reduced insulin in your brain, the Tau proteins become hyperphosphorylated and begin to form tangles, killing neurons.
This picture shows what I was mentioning with Tau-proteins. You can see what happens to the neurons and how the tangles lead to neuron death.
The implications of these findings are scary. As if we needed another reason to eat healthy, developing Type-II diabetes might lead to Alzheimer’s as well. With obesity on the rise in America, this is just another thing to worry about.