Exam3 HDL LDL PLA2 CoQ and radicals.txt

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Exam3 HDL LDL PLA2 CoQ and radicals.txt
2014-10-23 00:44:50
applied nutrition

applied nutrition
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  1. Why do we need AA (from linoleic) EPA and DHA (from a-linolenic)
    • They go onto phospholipids to become part of the membranes, mostly SMOOTH ER and NUCLEAR membranes
    • Phospholipase A2 (PLA2) then acts to chop these acids on the membranes and they are then generated into 2 enzymes in the ER:
    • 1. cyclooxygenase
    • 2. lipoxygenase
    • Responsible for formation of prostoglandins, thromboxanes and leukotrienes
  2. Phospholipase A2 role and how is activated
    • Activated by Calcium, or other signaling molecules such as JNK-MAPK, P38-MAPK
    • Chops the AAs (also EPA and DHAs) off of the PHOSPHOlipid membranes of the Smooth ER and nucleus
    • It uses these to make the two enzymes:
    • 1. CYCLOoxygenase
    • 2. LIPOxygenase, both which form prostoglandins, thromboxanes and leukotrienes
    • Cytochrome p450
    • Responsible for HYDROXYLATING steroids
  3. Major source of radicals
    • 1. Autooxidation of CoQ: floats in the matrix (NOT membrane-bound), picking up e-’s from FADH and transports it to site 2. When it floats in the aqueous envir. it acts with its MAIN FXN, to autooxidize B4 getting to the membrane where it can then act as an ANTIOXIDANT, a source of superoxide anions
    • 2. NADH can Autooxidize:
  4. Why is Damage NOT needed for inflammation
    Increase in radical species ALONE can activate PLA2, in order to lead to inflammation
  5. What aids in LACK of control of inflammation
    • 1. Inefficiencies of Vitamin C and E
    • 2. Not enough Essential FAs
  6. HDL function
    Donates fxnl proteins to LDLs to get them OUT of the blood to locations where CHOLESTEROL is NEEDED
  7. Chylomicron
    • Lipoproteins made by intestinal cell, in the blood stream.
    • HDLs activate ApoCII
    • Lipoprotein lipase enzyme also recognizes ApoCII receptor, binding and allowing it to CHOP off Fatty acids, so it can move out of the blood stream
  8. Apo-protein role
    • Needed for HDLs to recognize and bind and donate fxnl proteins to LDLs to get them out of blood
    • Play a role through the receptor: Lipases bind to APO receptors to chop up CHYLOMICRON
  9. What if lipases don’t get used
    If they don’t bind to Apo-receptors on chylomicrons, they get eaten by macrophages, cause pro-inflammatory response, increase disease progression and HEART DISEASE
  10. Macrophages impact on lipoproteins
    • They will attack if ApoB100 is present
    • recognize lipoprotein damage: ONLY recognize OXIDIZED HDL and LDLs..result is attack by macrophages