Diabetes Flashcards
Metformin: What is its primary mechanism of action?
- Metformin activates AMPK in hepatocyte mitochondria.
- This inhibits ATP production.
- This blocks gluconeogenesis and subsequent glucose output. It also blocks adenylate cyclase which promotes fat oxidation.
- Both help to restore insulin sensitivity.
Metformin: What does it target?
AMP activated protein kinase in Hepatocyte mitochondria
Metformin: What is its main side effect?
GI side effects with high doses (20-30% of patients)
e.g. Abdominal pain, decreased appetite, diarrhoea, vomiting)
Dipeptidyl-peptidase 4 (DPP-4) inhibitors: Give the name of one.
Sitagliptin
Dipeptidyl-peptidase 4 (DPP-4) inhibitors: What does it target?
DPP-4 (enzyme) in the vascular endothelium
Dipeptidyl-peptidase 4 (DPP-4) inhibitors: What is the role of DPP-4 enzymes?
Metabolism of incretins in the plasma. Therefore, these inhibitors increase incretin levels.
Dipeptidyl-peptidase 4 (DPP-4) inhibitors: What is the role of incretins?
- stimulate the production of insulin when it is needed (e.g. after eating)
- reduce the production of glucagon by the liver when it is not needed (e.g. during digestion)
- slow down digestion
- decrease appetite
Dipeptidyl-peptidase 4 (DPP-4) inhibitors: Where are incretins released from?
Enteroendocrine cells
Dipeptidyl-peptidase 4 (DPP-4) inhibitors: What are the main side effects?
- Upper respiratory tract infections (5% of patients) Flu-like symptoms e.g. headache, runny nose, sore throat
- RARE: Serious allergic reactions
Dipeptidyl-peptidase 4 (DPP-4) inhibitors: Who shouldn’t be given this drug?
patients with pancreatitis
Sulphonylureas: Give the name of a Sulphonylurea.
Gliclazide
Sulphonylureas: What does it target?
ATP-sensitive potassium channel in Beta pancreatic cells.
Sulphonylureas: What is its primary mechanism of action?
- Inhibits the ATP-sensitive potassium (KATP) channel on the pancreatic beta cell. Potassium can no longer leave the cells.
- This causes depolarisation which stimulates Ca2+ influx and subsequent insulin vesicle exocytosis.
Sulphonylureas: What are its main side effects?
- Weight gain
- Hypoglycaemia
Sulphonylureas: How can weight gain be mitigated?
Concurrent administration of metformin