Insulin is a hormone produced by the pancreas that regulates blood sugar levels. It allows glucose in the bloodstream to enter cells and be used for energy. Without insulin, blood sugar builds up and cells are deprived of energy, leading to serious health issues. Diabetes occurs when the body does not produce enough insulin or the cells do not respond properly to insulin. Historically, insulin was purified from animals but is now commonly produced through recombinant DNA technology using modified bacteria. This process involves isolating the human insulin gene, inserting it into bacterial DNA, and causing the bacteria to express and mass produce human insulin.

1. INSULIN
 Definition
 Function
 Importance
 History
 Production

2. Insulin
-Insulin is a hormone that regulates the
amount of glucose (sugar) in the blood
and is required for the body to function
normally.
-Insulin is produced by cells in the
pancreas, called the islets of
Langerhans.

3. How does Insulin works?
 Certain cells in the body change the food ingested
into energy or blood glucose that cells can use.
Every time a person eats, the blood glucose rises.
Raised blood glucose triggers the cells in the islets
of Langerhans to release the necessary amount of
insulin. Insulin allows the blood glucose to be
transported from the blood into the cells.
Researchers do not yet know exactly how insulin
works, but they do know insulin binds to receptors
on the cell's membrane. This activates a set of
transport molecules so that glucose and proteins
can enter the cell. The cells can then use the
glucose as energy to carry out its functions. Once
transported into the cell, the blood glucose level is
returned to normal within hours.

4. Importance of Insulin
 Without insulin, the blood glucose builds up in the
blood and the cells are starved of their energy
source. Some of the symptoms that may occur
include fatigue, constant infections, blurred eye
sight, numbness, tingling in the hands or legs,
increased thirst, and slowed healing of bruises or
cuts. The cells will begin to use fat, the energy
source stored for emergencies. When this happens
for too long a time the body produces ketones,
chemicals produced by the liver. Ketones can
poison and kill cells if they build up in the body over
an extended period of time. This can lead to serious
illness and coma.

5. Diabetes
 People who do not produce the necessary
amount of insulin have diabetes. There
are two general types of diabetes.
 The most severe type, known as Type I or
juvenile-onset diabetes, is when the body
does not produce any insulin.
Type II diabetics produce some insulin, but it
is either not enough or their cells do not
respond normally to insulin. This usually
occurs in obese or middle aged and older
people.

6. History
250 BC-Apollonius of Memphis coined
the name "diabetes” meaning "to go
through".
1869- Paul Langerhans, a German
medical student, discovered islet cells in
the pancreas
1910- Sharpey-Shafer of Edinburgh
suggested a single chemical was
missing from the pancreas. He proposed
calling this chemical "insulin."

7. 1921- Frederick G. Banting and Charles H.
Best successfully purified insulin from a
dog's pancreas.

8. In 1919, Moses Barron, a researcher at the
University of Minnesota, showed blockage of the
duct connecting the two major parts of the
pancreas caused shriveling of a second cell type,
the acinar. Banting believed that by tying off the
pancreatic duct to destroy the acinar cells, he
could preserve the hormone and extract it from
islet cells.
In May 1921, Banting and Best tied off pancreatic
ducts in dogs so the acinar cells would atrophy,
then removed the pancreases to extract fluid from
islet cells. Meanwhile, they removed pancreases
from other dogs to cause diabetes, then injected
the islet cell fluid. In January 1922, 14 year-old
Leonard Thompson became the first human to be
successfully treat-ed for diabetes using insulin.

9. 1936- researchers found a way to make insulin
with a slower release in the blood. They added a
protein found in fish sperm, protamine, which
the body breaks down slowly. One injection
lasted 36 hours.
1950- researchers produced a type of insulin
that acted slightly faster and does not remain in
the bloodstream as long.
1970- researchers began to try and produce an
insulin that more mimicked how the body's
natural insulin worked: releasing a small amount
of insulin all day with surges occurring at
mealtimes.

10. -Researchers continued to improve insulin but the basic
production method remained the same for decades.
Insulin was extracted from the pancreas of cattle and
pigs and purified. The chemical structure of insulin in
these animals is only slightly different than human
insulin, which is why it functions so well in the human
body. (Although some people had negative immune
system or allergic reactions.)
Early 1980- biotechnology revolutionized insulin
synthesis. Researchers had already decoded the
chemical structure of insulin in the mid1950s. They
soon determined the exact location of the insulin
gene at the top of chromosome 11. By 1977, a
research team had spliced a rat insulin gene into a
bacterium that then produced insulin.

11. Recombinant DNA technology
 Joining together of DNA molecules from
two different species that are inserted into
a host organism to produce new genetic
combinations.
 Genetically modified organism is the
product of this experiment.
organism whose genome has been
engineered in the laboratory in order to favour
the expression of desired physiological traits
or the production of desired biological
products.

12. Process of Producing Insulin Using
Recombinant DNA Technology

13. First Step (Preparing)
 The human gene is isolated. The mRNA is
taken from the cell of islet of Langerhans.
 Messenger RNA is a molecule of RNA that encodes a
chemical "blueprint" for a protein product.
 The isolated gene contains the code of the human DNA for
the production of insulin.
 The plasmid DNA of the bacterial cell is taken
out of the cell.
 NOTE: Escherichia coli (E. Coli) bacteria is widely used
in producing insulin but yeast may also be used.

14. Second Step (Cutting)
 The plasmid DNA of the bacteria is cut out
producing plasmid ring which is an empty
segment of the DNA.
A Restriction Enzyme is an enzyme that
cuts DNA at specific recognition nucleotide
sequences known as restriction sites.
A segment of DNA known as sticky ends.

15. Third Step (Combining)
 With the plasmid ring open, the gene
obtained from human cell that contains the
code of protein responsible for the
production of insulin is inserted into the
plasmid ring and the ring is closed. The
human insulin gene is now combined with
the bacterial DNA plasmid.

16. Fourth Step (Inserting)
 The resulting DNA is inserted back to the
bacteria.

17. How does the resulting bacteria
works?
 The cells need nutrients in order to grow,
divide, and live. While they live, the bacterial
cell processes turn on the gene for human
insulin and the insulin is produced in the cell.
When the bacterial cells reproduce by
dividing, the human insulin gene is also
reproduced in the newly created cells.

18. Insulin
Presented by: Vince Lowel H. Rosete
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