Diabetes

Question 1

What is the half life of insulin?

Answer 1

3-5 mins

Question 2

How does an increase in glucose lead to insulin release?

Answer 2

Increase of glucose increases ATP, which leads to a slight depolarization and influx of Ca, causing insulin to be released

Question 3

What type of receptor is the insulin receptor?

Answer 3

Tyrosine protein kinase, phosphorylates IRS (insulin receptor substrates) leading to downstream pathways

Question 4

What happens in type 1 diabetes?

Answer 4

Beta cells are selectively destroyed resulting in insulin deficiency

Question 5

What happens in type 2 diabetes?

Answer 5

Tissue resistance is build against insulin resulting in no insulin action

Question 6

What are the 2 diagnostic criteria for diabetes?

Answer 6

Elevated glucose -> fasting plasma glucose, oral glucose tolerance test
Increased Hemoglobin A1C (glycosylated hemoglobinm more long term snapshot)

Question 7

What is the first line treatment of diabetes?

Answer 7

Well balanced diet
Exercise for weight loss
Education: rationale behind controlling glucose intake

Question 8

Why can’t you take an insulin pill?

Answer 8

1st pass metabolism

Question 9

What are the different types of insulin, and what do they do?

Answer 9

Regular: dimerizes, but needs to be monomeric to act
Rapid acting: unable to dimerize
Regular short acting: can’t dimerize
NPH: protamine makes it soluble (lower peak but lasts longer)
Long acting: Low peak but constant action

Question 10

What drugs can you take for Type 2 diabetes?

Answer 10

Metformin (biguanides) - goto for type2
sulfonylureas
GLP1 receptor agonists
DDP4 inhibitors
Thiazolidinediones 
SGLUT2 inhibitors
Alpha-glucosidase inhibitors

Question 11

What does Metformin do?

Answer 11

Supresses hepatic glucose production (increases AMPK activation)
inactivating glucagon receptor

Question 12

What do sulfonylureas, GLP1 receptor agonistsm and DDP4 inhibitors do?

Answer 12

Promote insulin secretion

Question 13

How do sulfonylureas such as Glyburide work?

Answer 13

Blocks the ATP-sensitive K channel

Side effects: loss of efficacy, hypoglycemia, weight gain

Question 14

How do GLP1 receptor agonists such as Liraglutide work?

Answer 14

Increases cAMP to promote insulin secretion and growth of beta cells, impairs glucagon secretion

Question 15

How do DDP4 inhibitors such as Sitagliptin work?

Answer 15

Inhibits enzyme that inactivates endogenous incretins

Question 16

How do Thialidinediones and Amyin analogues work?

Answer 16

Decrease insulin resistance

Question 17

How do Thiazolidinediones such as Rosiglitazone and Pioglitazone work?

Answer 17

Act on different tissues to increase insulin sensitivity
Side effects weight gain, heart failure, bladder tumor
Binds to TFs for lipid/glucose enzymes

Question 18

How do amylin analogues such as pramlintide work?

Answer 18

Affects neural transmission to inhibit glucagon secretion

Question 19

How do SGLUT2 inhibitors such as Canaglifozin work?

Answer 19

Inhibits renal reabsorption of glucose to increase its excretion
Side effects: UTIs (glucose rich urine), orthostatic hypotension (diuretic effect, RAAS_

Question 20

How do alpha glucosidase inhibitors such as acarbose work?

Answer 20

Blocks intestinal glucose absorption
delays ingestion/digestion of starch
doesn’t cause hypoglycemia because doesn’t touch insulin
Side effects: gastrointestinal