“Understanding Lipid Metabolism and Cholesterol Synthesis: A Case Study in Hypercholesterolemia Treatment”

Book for this class: 
ANATOMY AND PHYSIOLOGY; THE UNITY OF FORM AND FUNCTION (LL)
BIOS251 WK 2 CASE
STUDY
Introduction
recap:
Lipids are essential
energy-yielding nutrients or macronutrients that are organic and composed of
carbon, hydrogen, and oxygen – but lack nitrogen. Characteristics of lipids
include:
•       Lipids
are characterized by their insolubility in water meaning that lipids do not
dissolve in water.
•       All
lipids are hydrophobic. 
•       Most of
the fat we eat is in the form of triglycerides.
Discussion
on Lipids
Chylomicrons
transport fats from the intestinal mucosa to the liver. Chylomicrons release
triglycerides and a portion of cholesterol into the liver, where they are
converted into low-density lipoproteins (LDL). LDL then transports cholesterol
and fat to the body’s cells. High-density lipoproteins (HDL) help lipids and
cholesterol return to the liver for elimination. When oxidized LDL cholesterol
levels rise significantly, atheroma develops in the arterial walls, causing
atherosclerosis. Because of its high cholesterol content, LDL is considered the
most atherogenic lipoprotein. HDL cholesterol can traverse the atheroma and
remove cholesterol.
Scenario/Summary
The following case
study demonstrates the importance of understanding the biochemical pathway of
cholesterol synthesis in treating clients diagnosed with
hypercholesterolemia.  
A 43-year-old client visits the
primary care practitioner for a cardiac stress test. As the nurse inquires
about the client’s past medical history, she learns that the client has a
strong family history of premature cardiac disease, and his two older brothers
are currently being treated for hypercholesterolemia. Other than mild
exertional dyspnea (shortness of breath), a review of systems is otherwise
negative. A physical examination reveals a body mass index of 31 kg/m² and an
abdominal waist circumference of 40 inches (102 cm), which, based on your
nursing education, is considered moderate abdominal obesity. The nurse educates
the client about simvastatin, a drug that inhibits Hydroxymethylglutaryl-CoA
(HMG-CoA) reductase, an enzyme needed for cholesterol synthesis in the
liver. 
Deliverables
Please
address the following questions in complete sentences.
1)    What clues in this clinical vignette make the
prescription of atorvastatin necessary for the treatment of this client’s
hypercholesterolemia?
2)    Explain the chemical structure and synthesis
of high-density lipoprotein (HDL), low-density lipoprotein (LDL), and
Very-low-density lipoprotein (VLDL) cholesterol.  Be sure to specify if HDL/LDL/VLDL is healthy
or unhealthy. 
3)    Describe the chemical structure of cholesterol
and lipids (fats).
4)    fibrates are a type of cholesterol-lowering
medication prescribed to lower triglyceride levels by increasing cells’ uptake
and subsequent usage of fatty acids to make what?
5)    Describe the difference between saturated vs
unsaturated fatty acids.