Gluconeogenesis- Metabolism of Carbohydrates

1. GLUCONEOGENESIS
-Dr. Rushikesh K. Joshi, PT
-MPT (Neurology)
1Dr. Rushikesh K. Joshi, PT (MPT Neurology)

2. Introduction
• The synthesis of glucose or glycogen from
non-carbohydrate compounds is called as
GLUCONEOGENESIS.
• Major precursors for this process are
pyruvate, amino acids, and glycerol.
• Mainly occurs in the cytosol.
2Dr. Rushikesh K. Joshi, PT (MPT Neurology)

3. The source of pyruvate and oxaloacetate for
gluconeogenesis during fasting or carbohydrate
starvation is mainly amino acid catabolism.
Some amino acids are catabolized to pyruvate,
oxaloacetate, or precursors of these.
Muscle proteins may break down to supply amino acids.
These are transported to liver where they are
deaminated and converted to gluconeogenesis inputs.
Glycerol, derived from hydrolysis of triacylglycerols in fat
cells, is also a significant input to gluconeogenesis.
3Dr. Rushikesh K. Joshi, PT (MPT Neurology)

4. Dietary & muscle
proteins
Amino acids
Triglycerols
glycerol
Fatty acids
Noncarbohydrate precursors of
glucose
4Dr. Rushikesh K. Joshi, PT (MPT Neurology)

5. 5Dr. Rushikesh K. Joshi, PT (MPT Neurology)

6. Main sites of gluconeogenesis:
• Major site: Liver.
• Minor site: Kidney.
• Very little:
– Brain.
– Muscle (skeletal and heart).
In liver and kidney it helps to maintain the
glucose level in the blood so that brain and
muscle can extract sufficient glucose from it to
meet their metabolic demands.
6Dr. Rushikesh K. Joshi, PT (MPT Neurology)

7. Importance of gluconeogenesis
• Brain , CNS, RBCs, kidneys are dependant on
glucose for continuous supply of energy.
• Through this process, under the lack of
glucose in body ( starvation/fasting) , the
protiens fats are converted to glucose.
7Dr. Rushikesh K. Joshi, PT (MPT Neurology)