[Music] Most foods that we eat have a combination of carbohydrates proteins fats along with fiber
minerals and other nutrients. In this video we will focus on carbohydrates such as starches and sugars
in our foods to understand how they are related to the rise and fall of blood glucose levels
Let's say you eat an apple. Starches and sugars present in the apple are digested or broken
down into simple sugars such as glucose which is then absorbed from the intestine and enters the
bloodstream. A high blood glucose level signals the pancreas to secrete insulin into the blood
Muscle fat and other cells in the body require insulin for taking in glucose from the blood
to provide energy for movement cellular functions and growth. Any excess glucose is stored in cells
as glycogen and used later. Another signal that prepares our body to produce insulin
comes from intestines that are full of food. This signal is delivered to the pancreas via
a protein hormone called GLP-1. The signal itself is naturally regulated meaning after a few minutes of
action glp-1 is destroyed by an enzyme called DPP4. This ensures that the pancreas does not
overproduce insulin. Cells in our brain require a steady blood glucose level to function normally
to ensure normal brain function our body stores glucose in the form of glycogen. Liver has the
largest store of glycogen in our body During times of fasting a hormone called glucagon directs
conversion of stored glycogen into glucose to maintain the blood glucose levels. During
extreme starvation the liver is also capable of converting protein and lipid building blocks into
glucose. Another organ that plays an important role in managing blood glucose levels is the kidney.
Its normal function is to filter out waste materials from our blood and flush it out as urine.
During this process glucose in the blood is also filtered out. Our body has a mechanism to reabsorb
this glucose by a special glucose transporter protein. This ensures that there is no wastage.
A quick finger stick test can be used to measure the blood glucose levels at any given
time. Blood glucose levels below 70 milligrams per deciliter is considered too low and should
be addressed immediately. While levels higher than 200 milligrams per deciliter about two hours after
a meal is considered too high. Prolonged periods of high blood glucose levels can cause glucose
to stick to proteins in the blood. The amount of sugar bound to hemoglobin provides an assessment
of the average level of blood glucose over an extended period of time this measure is called
hemoglobin A1c or HbA1c. High numbers indicate inadequate management of blood glucose levels.
So one of the goals in diabetes treatment is to reduce the HbA1c numbers.
Diabetes is either caused by the absence of insulin, inadequate levels, or improperly
functioning insulin. The main symptom seen in diabetes is high blood glucose levels. In order to
maintain the blood glucose levels within a narrow range individuals living with diabetes can change
their diet and lifestyle. Changing diet means the amount of carbohydrates that enter the bloodstream
is limited. Changing lifestyle or adding exercise can help use more of the glucose from the blood.
If no insulin is produced by the body such as in type 1 diabetes the individual has to take insulin
injections. However if insulin is produced in the body a number of different approaches can be used
to manage blood glucose levels. usually the first medication given to an individual diagnosed with
diabetes is a Biguanide called metformin. Although the mechanism of action of this
medication is not fully understood it is known to decrease the amount of glucose released from
liver. Some reports suggest that it increases the efficiency of glucose uptake by fat and
muscle cells by increasing insulin sensitivity. Both activities reduce blood glucose levels
Other approaches to reduce addition of glucose to the bloodstream include blocking the digestion of
carbohydrates by a class of medications called alpha glucosidase inhibitors so the undigested
sugars are removed in the bowels. Another approach is blocking reabsorption of glucose
from the kidney by a class of medications called sodium glucose transporter 2 or SGLT2 inhibitors.
These medications help flush out excess glucose in the urine. Several classes of medications increase
insulin secretion. For example, sulfonylureas and meglitinides act on the pancreas to increase
insulin secretion. Whereas thiozolidine diones or TZDs increase insulin sensitivity of cells and
the efficiency of glucose uptake by them. The class of medications called Gliptins are DPP4 inhibitors
that block the function of the regulator DPP4, thereby prolonging the life of the GLP-1 hormone,
which in turn signals increase in insulin production. Synthetic GLP-1 analogues are
stable molecules that mimic the function of the GLP-1 hormone. They promote satiety and can lead
to weight loss. Some of these medications can be taken just once a week making them user friendly.
Diabetes is a progressive metabolic disorder. The first medication prescribed after diagnosis
is commonly metformin. Over time one or more other classes of medications
may be added to the treatment plan for better management of blood glucose levels.
In really advanced stages the pancreas may stop making insulin altogether. At this stage
insulin injections may be necessary for managing blood glucose levels. To learn
more about diabetes and its various treatment approaches in molecular detail visit PDB-101.