Type 2 Diabetes Mellitus (2)
So as you saw in the video, type 2 diabetes there's no problem with the beta cells' production of insulin in the pancreas initially. Instead, the problem begins with insulin resistance in the muscles and in the skeletal muscles. The muscles are not taking in enough glucose because of this decreased sensitivity to insulin, so the glucose you saw gets let into the cell by that insulin molecule, and because the insulin's not able to do its job because the muscle is resistant, the muscle thinks it's being starved, doesn't have enough energy to do the work that it needs to do, and so these starved muscles send out a message to the liver to increase the glucose output, and this is the wrong message, because there's plenty; there's actually plenty of glucose, it's just that the muscle doesn't know that that glucose can't get into the cell. And so the liver then increases glucose output, which again is the wrong thing, but the muscle sent the wrong signal, and this results in excess sugar or glucose in the blood. To deal with that, the pancreas then increases production or secretion of insulin in attempt to reduce the blood glucose levels, and eventually these beta cells of the pancreas become overworked and dysfunctional over time from having to send more and more insulin out into the system to eventually allow some blood glucose to get into the muscle. When that happens, there's an impaired ability to secrete insulin that leads to elevated, continuously elevated, blood glucose levels, and you can have damage to healthy tissue. And so what you'll see here at the end is that as those beta cells start to become dysfunctional, type 2 diabetes starts to mirror type 1 diabetes and the effects of it, but it's important to note that that's not where it starts. Initially, in type 2 diabetes, there is no problem with the beta cells making enough insulin; it's just that the muscle is resistant to letting the insulin do its work. So these are the steps of the development of type 2 diabetes.