Lipid Metabolism Flashcards
Functions of lipids
- Major source of energy for body
- Major components of cell membranes
- Cell signalling
- Facilitate absorption of fat-soluble vitamins
- Biosynthetic precursors
- Protection & Insulation
Steps of lipid metabolism
- Lipid digestion
- Lipid absorption
- Lipid transport
- Lipid catabolism
- Lipid biosynthesis
Steps of lipid metabolism
- Lipid digestion
- Lipid absorption
- Lipid transport
- Lipid catabolism
- Lipid biosynthesis
How do bile salts and pancreatic lipase work
• Lipid digestion is controlled by digestive hormone, cholecystokinin
(CCK) - stimulate release of pancreatic lipase & bile salts
• Bile salts – Amphiphatic compound that emulsify fat to form micelles
• Pancreatic lipase – hydrolyse TG into monoglyceride, FA, glycerol
What is the function and types lipoproteins
Hydrophobic lipids require special transport proteins – lipoproteins
4 types of Lipoproteins:
1. Chylomicrons – highest %TG, lowest density
2. Very low density lipoproteins (VLDL) – high %TG
3. Low density lipoproteins (LDL) – Highest %cholesterol (Bad cholesterol)
4. High density lipoproteins (HDLs) – Highest %protein, (Good cholesterol)
What are the 4 classes of lipoproteins
What are the three different lipid transport pathways
- Exogenous (chylomicrons)
- Endogenous (LDL)
- Reverse transport pathway (HDL)
What process converts fatty acids into acetyl CoA
Beta-oxidation of fatty acids
What is ketogenesis and when is it used
• Synthesis of ketones/ketone bodies
• Occurs during starvation, they occur when there is low glucose so acetyl CoA is converted to ketone bodies
• From fatty acids and ketogenic amino acids
• Energy source used by brain as they can cross bbb
What is dka and why is dangerous
Diabetic ketoacidosis when lack of insulin to use glucose or too low blood sugar in diabetic patient, there are too many ketones produced which causes acidosis in patients
Process of ketogenesis
Role of cholesterol
• Cholesterol contain 4 fused rings. It is made from Acetyl CoA
• Makes cell membranes, precursor of bile acids, steroid
hormones and Vitamin D
Process of cholesterol synthesis
5 key steps in atherogenesis
- Endothelial dysfunction
- Formation of lipid layer/fatty streak within vessel wall
- Inflammation
- Foam cell formation
- Thrombosis to heart attack or stroke
