Blood Glucose Regulation and Diabetes

Hi this is Tom from www.zerotofinals.com. I'm going to go through some quick things

today just about blood glucose regulation and how this relates to type

1 diabetes and type 2 diabetes. So let's get straight into it. So I'm going to go

ahead and talk about some key organs that are important when looking at the

regulation of blood glucose. So the first organ to start with is the small

intestine. This sits in the middle of the abdomen, it's where your food is

broken down and absorbed into the bloodstream as glucose. So anytime you

eat carbohydrates this is where it's absorbed into the bloodstream. The next

important organ to be aware of is the pancreas. The pancreas produces insulin

in the beta cells and it produces glucagon in the alpha cells. Okay the

next organ is the liver. Now the liver is important because it stores glucose

so when there's plenty of glucose around it can store it as glycogen and it can

also produce glucose in a process called gluconeogenesis which converts things

like amino acids into glucose. The final organ is the muscles of the body. This is

where glucose is absorbed, stored as glycogen and can be used at a later time

when more glucose is needed. So there's a quick overview of the important organs

that are involved in glucose metabolism. Next I want to give a bit of a graphical

representation of how these organs affect the blood glucose level. So here

we've got a diagram. Along the bottom you can see this is supposed to represent a

blood vessel and then this inside is the bloodstream and these little blue

hexagons represent glucose molecules. So here for example this is just a nice

ordinary level of glucose in the blood. The body's very happy with this level. So

let's take a typical scenario where a person eats a large bowl of rice. That

rice enters their digestive system into the small intestines, is broken down into

glucose and absorbed into the bloodstream. So now we have, as a

reaction to all of that new glucose, a rise in blood sugar levels. So what

happens now? Well the pancreas senses this rise in blood glucose level and it

produces a hormone called insulin. Now what this hormone insulin does is it

targets the liver and it targets the muscles and it tells them to absorb

glucose from the blood into the liver and muscles and store it as something

called glycogen. And this is a storage molecule for the glucose. So as a result

of this action the blood sugar level drops back down to normal and everybody's

happy. So let's take an opposite scenario. Let's imagine that the blood

glucose level is low. Now this might be because of increased demand for glucose

by the body. Let's say during exercise or during periods of intense thought

processes where the brain is using a lot of glucose. Now what happens here is the

brain senses that the blood glucose is low and it might trigger a hunger

response which means that more food will be entering to the small intestine

and absorbed as glucose. The other thing that will happen is the pancreas will

sense this low glucose and it will produce another hormone called

glucagon. What this glucagon does is it targets the liver and it targets the

muscles and from both of these it does the opposite effect of the insulin. It

causes glycogen to convert into glucose. It also tells the liver to produce new

glucose and this is a process called gluconeogenesis. So this means new

glucose being made and this is where glucose is made from either proteins or

other chemicals. So what happens if you have a situation of diabetes? Well

there's two types of diabetes. First we'll talk about type 1 diabetes and

that's quite simple to explain. Essentially it's where the pancreas

stops being able to produce insulin. So as the blood glucose rises to a level of

high blood glucose the pancreas can't signal to the liver or muscles to use

that glucose. So the blood glucose remains high and if the small intestine

keeps piling in more and more and more glucose this never gets depleted and the

person gets in a state of severe hyperglycemia and as a result several

other things happen. You end up with a situation of diabetic ketoacidosis and

ultimately is not compatible with life. So the only treatment for type 1

diabetes is to replace that insulin with a subcutaneous injection of synthetic

insulin. So that's type 1 diabetes. Type 2 diabetes is where you have this

chronic hyperglycemia from a life of high intake of carbohydrates and what

this causes is resistance in the liver and the muscles to the insulin. So what

you need is, so insulin is trying to tell the liver and muscles to take up this

glucose but because they're so used to this signal, they're so used to the

insulin that they become very resistant and you need more and more and more

insulin to give the same effect. So essentially the pancreas produces

tons of insulin and the liver and muscles respond less and less to this

signal and ultimately what happens is that the pancreas wears itself out and

so instead of being a high level of insulin the pancreas stops being able to

produce as much insulin and you end up with this situation of low insulin and

the end stages of type 2 diabetes with a chronically high level of glucose. So

that's a situation of we've been through how insulin is, how blood glucose

levels are controlled. We've been through what happens in type 1 and been through

what happens in type 2 diabetes and this video is really in preparation for

more videos that are yet to come about the different types of treatments for

type 2 diabetes. So keep an eye out for those. If you like this video please

check out the website at www.zerodefinals.com. Why not subscribe on the YouTube

channel and check out some of the other videos. So I'll see you next time.