Lipid Advanced Metabolism Flashcards
Endogenous lipid comes from where?
Within the body
Exogenous lipids come from where?
Outside the body through the diet e.g. burgers n pizz
Define Lipid
A biological substance that is insoluble in water but soluble in organic solvents such as alcohol, chloroform, ether, and acetone. Some phospholipids are not soluble in acetone & some have limited solubility in H2O.
What does the body use lipids for in terms of nutrition?
Primary source of fuel for the body
What is the significance of lipids to structure of cells?
- Gives cell membrane stability and rigidity
*Allow for transmembrane transport of important molecules
What kind of hormones have lipids
Steroid hormones such as… vitamin D, cortisol, and aldosterone.
What kind of fat produces heat?
Brown. Fat
What is the fat surrounding nerves and help conduct signals in the neuron?
Myelin sheet
List major lipids
*Free fatty acids
*Phospholipids
*Cholesterol (free & esterified)
*Triglycerides
*Glycolipids
*Prostaglandins
What are triglycerides made up of?
Glycerol esters combined with free fatty acids. Refer to Major lipid slide
What kind of fatty acid has no double bonds?
Saturated fatty acids
What kind of fatty acid has one double bond?
mono-unsaturated fatty acid
What fatty acid has 2 or more double bonds?
Polyunsaturated fatty acid
what’s the range of carbons for a short chain FA?
4 - 6 carbon atoms
What’s the carbon range for a medium - chain FA?
8 - 12 carbon atoms
What’s the carbon range for a long chain FA?
12 + carbon atoms
Complete the phrase; _____ are essential component of cell membranes.
Phospholipids
What acts as a detergent in clearing other fats out of the body?
Phospholipids
What is the term to describe a molecule that has a hydrophilic and hydrophobic structure?
Amphiphilic structure
Cis versus Trans fatty acids?
Where are phospholipids synthesized?
Liver & intestinal epithelium
What are three kinds of important phospholipids?
- Lecithin (phosphatidyl choline)
- Cephalins (phosphorylated ethanolamine, inositol, and serine)
- Spingomyelin (spingolipid)
Cholesterol has a ______ ring with side chain of carbon atoms.
Perhydrocyclophenanthrone ring with side chain of carbon atoms
Cholesterol (endogenous) is made from what?
Acetyl - CoA
What is the product of the enzyme aceto acetyl CoA synthetase?
Aceto acetyl CoA
What is the product of HMG - CoA Synthetase?
HMG - COA important for cholesterol or ketogenesis
What is the rate limiting enzyme in cholesterol synthesis?
HMG - CoA Reductase, a build up of HMG CoA will suggest a defect in HMG CoA reductase.
What are the important functions of cholesterol? (Name 4)
- Manufacture & repair of cell membrane
- Synthesis of Bile acids
- Synthesis of Vitamin D (steroid hormone)
- Precursor of five major classes of steroid hormone (Progestins, glucocorticoids, mineralocorticoids, androgen, and estrogen)
What are the five major classes of steroid hormones?
- Progestins
- glucocorticoids
- mineralocorticoids
- androgen
- estrogen
Surplus cholesterol goes where?
Into the bile acid synthesis pathway to help digest fat (turns fat into droplets)
Where is endogenous cholesterol made in the body?
The liver
What is the purpose of LCAT, lecithin cholesterol acyltransferase?
Trasnfer FA from Carbon 2 of phosphatidylcholin to cholesterol
If there is a deficiency with LCAT, lecithin cholesterol acyltransferase, what will we see?
Elevated levels of cholesterol
LCAT, lecithin cholesterol acyltransferase is bound to what protein?
Lipoprotein (HDL)
Acyl - CoA : cholesterol acyltransferase (ACAT) does what?
Catalyzes the formation of CoA and cholesterol ester
A person with high cholesterol is at risk for what?
Cardiovascular disease
Where does esterification of cholesterol by LCAT take place?
Plasma
Hydrolysis of cholesterol takes place where?
Liver
What fat is considered majority of neutral fats?
Triglycerides
What is triglycerides made of?
A glycerol ester + 3 Fatty acids
Triglycerides are a main storage form of _____?
Fats
Stored triglycerides can be catabolized into what during fasting or between meals?
Free fatty acids
Where do plasma triglycerides come from?
Intestine and liver
Intestinal triglycerides come from where?
Dietary fat
What organ is the manufacturer of plasma triglycerides?
Liver
If a patient requires a lipid profile what do they need to do?
Fast for about 12 hours
Cerebroside contains what?
Ceramide with a sugar at the 1 - OH moiety.