Cholesterol'''

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Cholesterol... The Silent Killer
Babylyn, Tonna, Lena, Janine
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Question
Familial hypercholesterolemia is the most common
inherited disease associated with mutations in
the LDL receptor (LDLR) gene on chromosome 19.
About 1 in 500 people is heterozygous for this
autosomal dominant trait and are therefore
genetically predisposed to having high levels of
LDLs and the associated pathogenesis of heart
attack or stroke. Imagine that despite lifestyle
changes, both of your parents have elevated LDLs
. What is your risk of also having high LDLs?
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What is Familial Hypercholsterolemia?

• Familial hypercholesterolemia (FH) is an
  inherited autosomal dominant disorder that causes
  severe elevations in total cholesterol and
  low-density lipoprotein (LDL) cholesterol. The
  defect concerns the cell membrane receptor for
  LDL. This is a binding defect due to a
  dysfunctional receptor.
• Heterozygous FH occurs approximately in 1 in 500
  persons.
• Homozygous FH occurs approximately in 1 in
  1,000,000 persons
• Associated with heart attack and stroke

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Available online at http//courses.washington.edu/
luca201/homework/pathway.gif
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LDL

• LDL circles fatty acids keeping them soluble in
  the aqueous environment
• LDL transports cholesterol and triglycerides from
  the liver and small intestine to cells and
  tissues which are taking up cholesterol and
  triglycerides
• LDL transports cholesterol to tissues which need
  it

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Difference Between Good and Bad Cholsterol

• LDL Bad Cholesterol. This is when too much LDL
  cholesterol in the blood can slowly build up in
  the inner walls of the arteries that feed the
  heart and brain. With other substances, it can
  form plaques in the arteries and will make them
  less flexible artherosclerosis.
• HDL Good Cholesterol. High levels of HDL seem
  to protect against heart attack. It tends to
  carry cholesterol away from the arteries.

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What are Your Chances?
The Gene for Hypercholesterolemia is found on
Chromosome 19. Homozygous FH (LL) is extremely
rare and serious. It becomes apparent in children
and without aggressive treatment, most patients
dont live past 30
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Risk of Hypercholesterolemia

• High levels of LDL can lead to premature
  atherosclerosis of the coronary arteries.
• Heterozygous FH (Ll) In men, this creates an
  increased risk of heart attack by the age of 60.
  For women, they are still at high risk, but it
  will occur about 10 years later than in men.
• Homozygous FH (LL) Those that inherit two
  mutated genes from their parents are even more at
  risk. They will develop waxy plaques on several
  areas of the skin, and will be at risk for having
  atherosclerosis beginning before puberty, and
  heart attacks before the age of 30.

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Treatment

• Diet Change
• Reduce fat intake to less than 30 of calories
  consume
• Substituting beef, pork and lamb, with low-fat
  diary products.

• Exercise
• Drug Therapy
• Statins-inhibit synthesis of HMG-CoA reductase, a
  rate limiting step in the hepatic synthesis of
  cholesterol. When this is limited, the liver
  increases the amount of LDL receptors, meaning
  more LDL is removed from circulation. This means
  that there is less cholesterol available to for
  atherosclerotic plaques that cause coronary heart
  disease (CHD)

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Analogy
Car crash on busy I-5 in Seattle. Cars in front
of you are stopped, cars behind you are still
going, and there are people on the sides of you.
You have a slim chance of not getting into an
accident. In FH, if both parents have it, there
is a good chance you will get it too. Poor
little mosquitoThe mosquito is being chased by a
little kid, there is a spider web in front and a
zapper light to the side. Will the mosquito make
it?