Introduction to Diabetes Mellitus 5 Flashcards
What are the effects of Insulin?
- decrease hepatic glucose output
- increase glycogenesis
- increase glucose uptake by muscles
- decreased proteolysis
- decrease lipolysis
- decrease ketogenesis
- growth, vascular effects, ovarian function
What is the main glucose transporter?
GLUT-4. It is primarily in muscles and adipose tissue. It has hydrophobic elements on the outside and a hydrophilic core allowing glucose through. It is insulin responsive as it sits in vesicles in the cytoplasm and waits to be recruited
What does Cortisol do?
Increases proteolysis when were stressed. Insulin prevents the oxidation of amino acids and increases re-synthesis of proteins
What are the effects of Insulin on the Liver?
- Increase amino acid uptake to increase protein synthesis
- decrease gluconeogenesis using amino acids
- Somatotropin, catecholamines, cortisol and glucagon all increase gluconeogenesis
- increase glycogenesis
What are the four counter-regulatory hormones?
- Glucagon
- Cortisol
- Catecholamines
- Somatotrophin
How does Insulin affect the adipocytes?
- It increases action of lipoprotein lipase so triglycerides can be broken down and therefore enter the adipocytes
- Increases formation of NEFA from glucose
- Promotes breakdown of glucose into glycerol and everntually triglycerides
- Ultimately, increase storage of glucose,/fats and prevent lipolysis
What fuels can the brain use?
- glucose
- ketone bodies
What can the brain not use as fuel?
Fatty Acids
Effect of Insulin on Ketone Body formation in the liver?
Insulin inhibits the conversion of Fatty Acyl CoA to Ketone bodies while glucagon promotes it.
What are the 3 ketone bodies?
- Acetone
- Acetoacetic Acid
- Beta-hydroxybutyric Acid
Whats the presentation of Diabetes Mellitus?
- proteolysis with weight loss
- hyperglycaemia
- glycosuria with osmotic symptoms (polyuria/polydispsia)
- Ketonuria
Where is insulin resistance located?
Liver, muscle and adipose tissue
What happens in LDL increase (Dyslipidaemia)?
Increase:
- in circulating NEFA
- Triglyceride
- LDL Cholesterol
Decrease:
- Lipoprotein Lipase Activity
- VLDL clearance
- HDL Cholesterol
How can you differ between T1 and T2 Diabetes Mellitus?
In T2, there is usually enough insulin to suppress Ketone body formation. In T1, there is usually high glucose and ketone body formation
What are the two pathways Insulin effects?
- Mitogenic (MAPK)
- Metabolic (PI3K-AKT)
