Diabetes Flashcards
What is diabetic ketoacidosis?
Complication of untreated T1 diabetes where the body has insufficient insulin for glucose to enter cells, so the body starts burning fatty acids and producing acidic ketone bodies - can lead to coma or even death.
Name some symptoms of ketoacidosis.
- hyperventilation
- n+v
- dehydration
- abdo pain
Name some symptoms of hyperglycaemia.
- extreme thirst
- dry mouth
- blurred vision
- drowsiness
Name some symptoms of hypoglycaemia.
- sweating
- feeling weak
- nausea
- shaky/tremors
What is lactic acidosis?
Low pH of bloodstream due to increased lactate, caused by acute or chronic underlying medical condition.
Describe the synthesis of insulin.
- pre-proinsulin synthesised in ribosomes on rER
- signal peptide (pre) removed once inside rER
- folding of proinsulin
- proinsulin transport to Golgi for modification
- C-peptide cleaved from middle of proinsulin to create 2 shorter chains joined by disulphide bonds
- C-peptide and insulin released in equimolar amounts
What measure in the blood is a good indicator of how much insulin is being produced?
C-peptide
What is the common history of someone being diagnosed with T1 diabetes?
Classically a young person with a recent history of viral infection (caused by genetic predisposition + environmental trigger).
Name the triad of symptoms for T1 diabetes.
Polyuria
Polydipsia
Weight loss
What are the symptoms of people with T2 diabetes?
Can have the triad, but more likely to have a lack of energy or recurrent infections.
How is T1 diabetes treated?
Insulin injections.
What is metabolic syndrome?
A group of symptoms and diseases e.g. Insulin resistance, hypertension etc. Associated with central adiposity.
Explain why diabetes can cause cataracts.
Some cells e.g. In the eye don’t require insulin and their glucose uptake is determined by extracellular glucose concentration. Extra glucose is metabolised by aldose reductase - this reaction depletes NADPH and produces sorbitol - less NADPH can lead to cataracts.
What is the use of measuring HbA1c?
Measures the amount of glycation in the blood - the higher the levels of glucose over the last few months, the higher HbA1c (more glucose has reacted with Hb).
Name the different types of insulin available.
Animal - from pigs or cows.
Recombinant DNA - ultrafast, rapid, short, intermediate, long or very long acting.
What does ultrafast, rapid, short, intermediate, long or very long acting mean?
Reflects the rate of absorption.
How does the rate of absorption affect when insulin needs to be given?
Slower acting insulin needs to be given earlier before a meal as it takes longer for the peak to be reached.
What is Novomix 30?
A combination of insulins - contains 30% rapid acting and 70% slow acting - this means that you can inject it fewer times a day.
Name a rapid acting insulin.
Novorapid.
Name a short-acting insulin.
Actrapid.
What class of drug is metformin?
Biguanide.
What is the MOA of metformin?
- decreases insulin resistance
- decreases gluconeogenesis
- limits weight gain
- decreases risk of CVS events
Name some side effects of metformin.
- GI symptoms
- nausea
- lactic acidosis (rare)
Which diabetic drug would be suitable for someone with renal impairment e.g. CKD?
Sulphonylureas - they are metabolised by the liver.
Name a sulphonylurea.
Glicazide
What is the MOA of glicazide?
Sulphonylurea - stimulates beta cells to release insulin by antagonising ATP sensitive K+ channels and decreasing K+ efflux.
What diabetic drug is most suitable for someone who has a higher BMI?
Which drugs should not be given to these people?
Biguanides
Don’t give sulphonylureas as they stimulate appetite slightly.
What is the MOA of alpha-glucosidase inhibitors?
Blocks action of enzyme alpha-glucosidase, which inhibits glycogenolysis.
Name some side effects of alpha-glucosidase inhibitors.
GI side effects e.g. Flatulence, loose stools, diarrhoea.
What type of drug is pioglitazone and rosiglitazone?
Glitzones - used for T2DM.
What is the MOA of glitazones?
- increase insulin sensitivity
- decrease insulin resistance
Name 2 glucagon like peptide 1 therapies.
Exenatide
Liraglutide
What is the MOA of GLP1 therapies?
- increases insulin secretion
- decreases glucagon production
Name some side effects of GLP1 therapies.
- GI symptoms e.g. Loose stools, GORD
- nausea
What class are Linagliptin and Sitagliptin and what are they used for?
DPP4 inhibitors
T2DM
What is the MOA of DPP4 inhibitors?
-inhibit DPP4 activity, which increases GLP1 concentrations (which increases insulin secretion and decreases glucagon production).
If the therapies for T2DM are no longer working, what should be given to the patient?
Start them on insulin.
