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Untreated diabetic + ketosis = even higher blood sugar?

  1. Apr 14, 2015 #1
    Since most normal body cells do need insulin to take up glucose, do type 1 diabetics instead have to run off of ketone bodies when insulin is not present?
    *If this is the case, wouldn't weight loss in untreated type 1 diabetics actually make their blood sugar go even higher but also be necessary, since their other body cells can't function without ketone bodies for fuel?

    Thanks! :)
     
  2. jcsd
  3. Apr 14, 2015 #2
    In order to break down body fat or muscle, do you first have to undergo glycogenolysis and then gluconeogenesis?

    I assume ketone bodies (made in the liver from fatty acids) are just used as a way to export acetyl CoA (derived from body fat, fat from food, muscle, or protein from food) to other body cells... Is this right?

    In order to even break down fat and access the fatty acids, don't you have to be out of sugar to metabolize?
    Does the drop in blood sugar trigger glycogenolysis and then gluconeogenesis after glycogen stores are depleted?
    I was thinking that gluconeogenesis was the only way fat or protein could get broken down...

    Is that right...? :/ ...very confused... :(
    Thanks so much!
     
    Last edited by a moderator: Apr 21, 2015
  4. Apr 14, 2015 #3
    My understanding is that monosaccharides circulating in the bloodstream enter cells to undergo cellular respiration.
    Glucose requires insulin to enter cells, but fructose and galactose do not (insulin-independent)?

    Is the above statement correct?

    I was wondering, then, if untreated diabetics only ate fructose and galactose-would their blood sugar always be normal? They wouldn't need insulin, then, it seems...
     
  5. Apr 14, 2015 #4
    Glucose is taken into cells using GLUT proteins, which enable their facilitated diffusion. GLUT4 proteins found in muscles cells are not permanently present in the plasma membrane, and are usually kept in the cytoplasm. When insulin binds to its specific receptor outside the cell, thr GLUT4 proteins fuse with the plasma membrane, and glucose is then able to move into the cell. In reality of course, insulin concentrations vary continuously, and so does the number of these protein molecules present on the plasma membranes of muscle cells.

    Brain cells and liver cells have GLUT1 and GLUT2 proteins respectively, and these are always present in the plasma membrane of these cells, so their glucose uptake would continue even in the absence of insulin.
     
  6. Apr 14, 2015 #5
  7. Apr 14, 2015 #6
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