Insulin diabetes treatment

Question 1

Pre-pro insulin

Answer 1

Sequence cut off
Insulin folded = disulphide bonds – 2 cystine residues, join A and B region

Question 2

Storage of insulin

Answer 2

Hexamer stabilised by Zn2+ ions
Stable but not active

Question 3

Types of insulin

Answer 3

Animal
Human - DNA technology
Analogues - altered human insulin

Question 4

Insulin preparations

Answer 4

Short-acting: soluble, aspart, glulisine, lispro
Medium-acting: isophane
Long-acting: detemir, glargine

Question 5

Size of insulin

Answer 5

Monomer > dimer > hexamer > aggregates

Question 6

Humalin I

Answer 6

Contains protamine
Clustering of insulin, limiting diffusion

Question 7

Humanlin S

Answer 7

No protamine

Question 8

Protamine

Answer 8

Basic protein
Binds to negatively charged insulin and clusters insulin hexamers

Question 9

Rapid-acting insulin

Answer 9

Insulin aspart: Proline to aspartate substitution in B chain

Insulin lispro: Two substitutions in B chain

Insulin glulisine: Two substitutions in B chain. Asparagine to lysine then glutamic acid

Question 10

Long-acting insulin

Answer 10

Insulin glargine: Contains asparagine to glycine substitution in A chain. Two arginines added to carboxyl end of B chain. Less soluble

Insulin detemir: Covalently attached fatty acids, bind to albumin. Albumin and insulin compete for receptor, prolonging its action. Protects insulin from protease, increasing stability

Insulin degludec: Hexadecanedioc group added to B chain. Albumin binding multi-hexamers.

Question 11

Injecting insulin

Answer 11

Orally ingested insulin degraded by protease
Subcutaneous
Stomach, buttocks, thighs
Rotated to avoid lipohypertrophy
<25C

Question 12

Insulin pumps

Answer 12

Varied dose of rapid-acting insulin

Question 13

Type 1 therapeutics

Answer 13

Islet cell transplantation
Cells injected through catheter in upper abdomen

Stem cell derived beta cells