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Current time:0:00Total duration:6:57

Video transcript

diabetes mellitus is a syndrome that's caused by improper function of insulin and as a result there's dysregulation of the blood sugar levels this results in high blood sugar which is also known as hyperglycemia but what exactly does this all mean to get a better idea let's first go over the body's normal regulation of blood sugar and to do that I'm going to just bring in a diagram here so in this diagram you'll see up here you have the esophagus that goes into the stomach and into the beginning portion of the intestines and then here in pink represents a blood vessel and then in yellow here is the pancreas there are three major types of nutrients that your body uses for energy there's fat protein and carbohydrates and we're going to be focusing on carbohydrates I'm going to just abbreviate that CH O which is a which stands for carbon hydrogen and oxygen which is the chemical makeup of carbohydrates so the carbohydrates that we eat go through our soffits and into our stomach and they start to get digested and as they enter into the intestines they're digested down into glucose and glucose is a simple sugar and it's very important in the body because cells throughout the body use glucose as energy and glucose I said is a type of sugar so sometimes people refer to as blood sugar levels and what they were referring to are the level of glucose in the blood so this glucose is absorbed through the GI tract into the blood vessels here and once it's in the blood it then travels to the cells of the body such as much muscle cells where it can be used for energy or the glucose in the blood can travel to the liver where it is stored to be used as energy in the future so let's see this happen this is where the role the pancreas becomes important because glucose on its own is not able to actually enter the cells like muscle cells or into the liver without the pancreas glucose would just become piled up in the blood luckily the pancreas here can sense this pile up or this increase in the blood sugar and it releases a hormone known as insulin and when the pancreas releasing the releases this insulin it kind of acts like a key that unlocks the cells of the body such as the muscle cells and the liver allowing the glucose to enter the cell so in the case of the muscle cells those cells can now start to do work and then in the case of the liver the glucose can be stored however this just kept going and insulin wasn't kept in check what would happen over time and use you can see here is that that blood glucose level would get too low and fortunately the pancreas can also sense when these blood glucose levels are getting too low and it stops secreting insulin and it starts to secrete another hormone known as glucagon and what glucagon does is it stimulates the liver to release this stored glucose back into the blood to replenish the blood glucose levels and eventually the blood glucose levels return to normal so let me draw a diagram here to help you remember how our bodies maintain the blood glucose levels so you can think of the maintenance of the blood glucose level as being a balance between insulin and if the balance is tipped in the direction of insulin here it will result in the unlocking of cells it will also allow the liver to store the glucose and then both of these things result in a lowering of the blood glucose level then as this gets too far the pancreas reacts and it then has glucagon to shift the balance by causing the release of that stored glucose which results in a raising of the blood glucose level all right so now that we have an understanding of how the body normally regulates blood glucose levels with insulin and glucagon what exactly is going on in diabetes mellitus well I mentioned at the beginning that diabetes mellitus is a syndrome that's caused by improper improper functioning of insulin and in a sense the insulin just doesn't work now this may be due to many different underlying causes such as the pancreas here not being able to produce the insulin the pancreas may just be producing too little insulin or for some reason the cells may not be receptive to the insulin and since that key mechanism doesn't unlock the cells to allow the glucose to get in regardless of the underlying mechanism though when you don't have insulin here to balance out the blood glucose levels this balance is going to be tipped in the favor of glucagon and as such what's going to happen is these effects of glucagon here are going to become more predominant so what you see in diabetes mellitus one of the characteristic findings is that there's going to be hyperglycemia and this is because the glucagon is causing the glucose from the liver to be released and since insulin isn't functioning properly this key effect here also isn't working so these cells aren't able to get all of this glucose that is in the blood so despite having all of this energy present in the blood the cells aren't able to use it so someone with diabetes is oftentimes very fatigued or tired and that's because they're not able to extract the energy from the blood and then lastly the body tries to compensate for this increased concentration of glucose here in the blood and what it tries to do is it tries to dilute the blood with water from cells and what happens is that all this water leaves the cells and then the the person becomes dehydrated so frequently someone with diabetes will be dehydrated and very thirsty so diabetes mellitus is a syndrome that's caused by dysfunctional insulin or lack of insulin resulting in an inability of the body to maintain its normal blood sugar balanced and you get this hyperglycemia here then over time actually this persistent hyperglycemia can actually cause damage to many vital organs in the body such as the nerves eyes and kidneys