Insulin is a
peptide hormone secreted by beta cells of the pancreas. Insulin has a number of
important functions in the human body; it helps control blood glucose levels
and allows your body to use glucose for energy.
 |
| Insulin is a hormone made by the pancreas |
What is the Function of Insulin in the Human Body?
What is Insulin?
Insulin is defined as a type of protein hormone that plays a
central role in controlling blood sugar levels in the body and allows our body
to use glucose from carbohydrates in the food we eat for energy or to store
glucose for future use.
Insulin consists of fifty-one amino acids, distributed
in two peptide chains (dimer) named A chain (with 21 amino acids) and B chain (with 30 amino acids), and the two chains can be combined by two disulfide bonds.
The human insulin has a molecular mass of 5808 Da
and the molecular formula is C257H383N65O77S6.
What is
responsible for insulin secretion in the body?
The hormone insulin is normally
secreted by the beta cells of the pancreas. Beta cells are found in islets
of Langerhans in the pancreas gland and then excreted directly into the
blood.
Insulin
travels and binds to its own receptors on the cell wall, opens it, and allows
sugar to enter the cell wall and burn to produce the energy needed for the
body. Hence, insulin has great importance as a private key opening
receptor in cells.
The Function of Insulin in the
Body
Insulin has a very important function in
the body, as it is secreted by the pancreas when the blood sugar level rises
above the normal limit for glucose and sugar to enter the cells to burn
it.
Insulin helps
control blood glucose levels by sending a signal to the liver, muscles, and fat
cells to absorb glucose from the blood. If the body has enough energy,
insulin refers to the liver to absorb glucose and store it as
glycogen. The liver helps convert glucose into glycogen, thereby reducing
the blood sugar level.
Insulin can be
infused under the skin of the arms, abdomen, thigh, or cripples.
The
main functions of insulin can be summarized as follows:
Insulin helps
control blood glucose level and keep it from getting too high (hyperglycemia)
or too low (hypoglycemia).
Insulin
promotes glucose uptake, lipogenesis, glycogenesis and protein synthesis of fat
tissue and skeletal muscle through the tyrosine kinase receptor pathway.
Insulin helps
regulate the plasma glucose homeostasis, as it counteracts glucagon and other
catabolic hormones.
Insulin also
plays an important role in other body functions, such as vascular compliance and
cognition.
Insulin and Diabetes Treatment
Insulin is
used medically to treat some types of diabetes, especially those who suffer
from type 1 diabetes, as they rely on obtaining insulin to survive because of
the inability of their pancreas to produce the hormone insulin.
How many types
of insulin are used for diabetes?
The insulin is
divided into five categories according to its ability to treat diabetes after
injecting it into the body. The five types of insulin used for
diabetes are:
Rapid-acting
insulin: This insulin is very fast in effect and it
covers insulin needs for meals eaten at the same time as the injection.
Short-acting
insulin: This takes longer to start working than
the rapid-acting insulins and covers insulin needs for meals eaten within 30-60
minutes.
Intermediate-acting
insulin: This covers insulin needs for about half
the day or overnight.
Mixed
insulin: This insulin contains a pre-mixed
combination of either rapid-acting insulin or short-acting insulin, together with
intermediate-acting insulin.
Long-acting
insulin: This covers insulin needs for about one
full day. Long-acting insulin is often combined, when needed, with rapid-acting
insulin or short-acting insulin.