Ketone Metabolism Flashcards
During what state are ketone bodies made
Fasting state
Ketone bodies are made from which excess molecule from beta-oxidation
Acetyl coA
Apart from ketone bodies which other 2 molecules are produced during the fasting state
acetoacetate and 3-hydroxybutyrate
What is ketoacidosis
Build up of ketone bodies
In which organelle of what cell does ketogenesis occur
Mitochondria of hepatocytes
Which organ uses ketone bodies during prolonged starvation
The brain
Function of HMG-CoA synthase
Forms HMG-CoA from acetyl-CoA
Which enzyme converts HMG-CoA to Acetoacetate
HMG-CoA lyase
What is a clinical manifestation of ketoacidosis
A strong fruity/sweet smelling breath
Production of what molecule causes a strong fruity/sweet smelling breath
Acetone
Which enzyme is needed to convert Acetoacetate to acetoacetyl-CoA
Thiophorase
Why is it only ketogenesis that occurs in the liver and not ketogenolysis
The liver does not have thiophorase
Why doesn’t ketone synthesis occur in RBCs
They have no mitochondria
What effect does glucagon and epinepherine have on ketogenesis
Glucagon and epinepherine increases lipolysis which increases ketogenesis
What effect does insulin have on ketogenesis
Insulin decreases lipolysis which decreases ketogenesis
Which type of diabetic patients are more likely to have ketoacidosis
Patients with type I diabetes not treated wit insulin because that can cause release of fatty acids from adipose, promoting ketogenesis
How can hormone sensitive lipase induce ketoacidosis
It will call more lipid metabolism leading to more productin of acetyl coA and hence more ketogenesis
How are alcoholics prone to ketoacidosis
They are usually hypoglycemic which causes fatty acid release from adipose, leading to ketone production in the liver