45- insulin i intro and early purification Flashcards
what are biologic drugs. what is their molecular weight, what are they manufactured using, and how are they administered
- vaccine, protein, antibody, nucleic acid
- normally high molecular weihgt (>2000) → no chemical synthesis
- manufactured using living things
- plants, animals, human, single cells
- generally injectable
- not able to survive digestive tract
- other routes (nasal spray, suppository) are possible
- digestive tract will ingest protein or nucleic acid
what is diabetes, what can it cause, how many people are affected, how many people die per year
- family of metabolic disorders
- chaaratcers by high blood sugar concentration (or low)
- cardivasulcar problems
- kidney disease
- skin ulcers
- eye damage
- > 170 million affect world
- 3.2 million deaths per year (leading cause) top ten causes of death in canada
what is insulin and what does it regulate, what does it promote
- hormone produced by the pancreas, in blood stream
- regulates metabolism of carbohydrates, fats, protein
- promotes absorption of blood glucose by fat and liver cells
- cells convert glucose into glycogen (glucose storage polymer) or fat
- insulin promotes removal of sugar in blood stream
what does high insulin include
- high insulin= low blood sugar
- glucose is converted to storage forms
- glycogens
- fats
- glucose is then unavailable to body cells
what does low insulin include
- low insulin=high blood sugar in blood
- storage glucose converted to glucose (soluble)
- body also begins to break down proteins (catabolism)
- can lead to damage
what are the characteristics of type 1 diabetes
- type 1 (10%)
- pancreas no longer produces insulin
- starts in late childhood
- autoimmune component (involved in process)
what are the characteristics of type 2 diabetes
- type 2 (90%)
- insulin resistance
- pancreas produces insulin but cells do not respond
- autoimmune component
- obesity
what was the progonosis for diabetes before 1923
- death
- disease starts in childhood for type 1
- die in early teenage years
- possible to extend lifespan slightly using special diets
what did the experiments by banting and best demonstrate
- surgically altered dogs to enable insulin isolation
- tired off pancreatic duct
- cells died leaving behind islets of langerhans
- isolated pancreatic extract from islets
- used dog pancreatic extract to treat diabetic dogs
- created by surgically removing pancreas (1921)
when did the first insulin experiments run and how did it turn out
- first human experiments failed (14 year old boy in 1922)
- dog insulin too impure
why does better purification methods of insulin give better results
- different animal sources (bovine)
- simply getting access to more raw material
- animal sources in slaughter houses
- small amounts in animal
- every time you purify you lose a bit of insulin
what are the animals you can isolate insulin from
- bovine → cows
- porcine → pigs
- equine → horses
- ichthyic → fish
why are their issues with animal source insulin
- mixture of insulin and other animal proteins
- proinsulin (immunogenic) → has similar amino acid sequence to insulin
- patients become allergic to a type of insulin
- switch every few years to dif animal source
- proinsulin has different structure and that’s why allergy the pro part is the problem
- glucagon
- somatostatin
- proteases
- slowly destroy other proteins in the drug
- limits the shelf life of insulin
what was the general isolation method in 1920s
- truck load of pancreases
- homogenization → blender
- clarification
- dialyze or centrifuge
- collect supranate
- separate liquids from solids, keep liquids
- serial precipitation
- isoelectric precipitation
- alcohol denaturation
how does clarification of biological suspensions work
- filtration of biological suspensions not practical
- colloids (fine suspensions) pass through filter
- oily materials filters clog very quickly
- solids suck
