PHRD5025 Biochem Lecture 11 (Bain) - Metabolic Regulation – Mechanisms and Applications I

  1. if a molecule is "saturated" what does that mean?
    it contains no double bonds
  2. in the well-fed state, the body will store ___ in the adipose tissue.
    triglycerides (TGs)
  3. enzymes that catalyze the hydrolysis of stored TGs
    lipases
  4. during fasting ____ provides energy
    adipose tissue
  5. how does low blood glucose trigger mobilization of TGs?
    through epinephrine & glucagon via adenylyl cyclase
  6. what do FAs bind to in the blood stream?
    albumin
  7. where does albumin transfer FAs to? (3)
    • 1) skeletal muscle
    • 2) heart
    • 3) renal cortex (kidneys)
  8. 1st stage of FA oxidation
    Image Upload 2-oxidation
  9. how many times does Image Upload 4-oxidation occur?
    the cycle repeats 2 carbons at a time until only acetyl-CoA remains

    ex: 14C FA undergoes 6 cycles
  10. where does b-oxidation occur in the cell?
    mitochondria
  11. signals liver, skeletal muscle, & adipose tissue that blood glucose is higher than necessary
    insulin
  12. carries message that blood glucose is too low
    glucagon
  13. body response to insulin
    glucose is taken up from the blood into cells & converted to glycogen & TGs
  14. body response to glucagon
    produce glucose through glycogen breakdown & gluconeogenesis, & by oxidizing fats to reduce use of glucose
  15. True or False - Insulin release increases fatty acid synthesis?
    true
  16. key enzyme involved in FA synthesis
    acetyl-CoA carboxylase
  17. key enzyme involved in glycogen breakdown
    glycogen phosphorylase
  18. glucogenic liver
    liver in the fasting state
  19. lipogenic liver
    liver in the well-fed state
  20. during starvation, how does the body compensate for the decrease in free CoA needed for b-oxidation?
    produce & export ketone bodies
  21. 3 important ketone body molecules
    • 1) acetone
    • 2) acetoacetate
    • 3) D-Image Upload 6-hydroxybutyrate
  22. where do reactions of ketone body formation occur?
    matrix of liver mitochondria
  23. what uses ketone bodies as fuel?
    extrahepatic tissues
  24. increased ketone bodies are found in... (2)
    • 1) severe starvation
    • 2) untreated diabetes
  25. major sterol in animal tissue
    cholesterol
  26. sterols are precursors of what significant biological molecules? (2)
    • hormones
    • bile acids
  27. accumulation of cholesterol in blood vessels, leading to obstruction/reduction of blood flow
    atherosclerosis
  28. narrowing of the arteries to the heart via atherosclerotic plaques, often leads to heart attack
    coronary heart disease
  29. rate limiting step during cholesterol synthesis
    HMG-CoA -> mevalonate (by HMG-CoA reductase)
  30. HMG-CoA activator
    insulin
  31. HMG-CoA inhibitors (2)
    • 1) glucagon
    • 2) cholesterol (neg feedback)
  32. mechanism of statin drugs
    • mevalonate mimics
    • initiate negative feedback to inhibit HMG-CoA reductase -> less cholesterol synthesized
Author
daynuhmay
ID
243310
Card Set
PHRD5025 Biochem Lecture 11 (Bain) - Metabolic Regulation – Mechanisms and Applications I
Description
Metabolic Regulation – Mechanisms and Applications
Updated