Diabetes Flashcards
(33 cards)
List classes of oral anti diabetic drugs
Biguanides, insulin secretagogues, thiazolidinediones (tzds), alpha glucosidase inhibitors, bile acid binding resins, amylin analogs, glifozins.
MOA and examples of biguanides
Decrease liver production of glucose.
Example: metformin
MOA and example of insulin secretagogues
Block inward rectifying K channel. Leads to depolarization and opening of voltage gated calcium channel. Calcium influx leads to insulin containing vesicle fusing to membrane.
Example: sulfonureas and meglitinide.
Differences between 1st and 2nd gen sulfonureas and meglitinide.
1st gen requires higher dose. 2nd gen lower dose with less side effect.
Meglitinide to be taken with meals, shorter half-life, more freq dosing.
MOA and example of tzds
Tzds increase insulin signal transduction to insulin receptors that have desensitized to elevated glucose.
Example: avandia and actos
Risks associated with tzds
Increased risks of MI
MOA and example of alpha glucosidase inhibitors
Block digestion of complex carbs. Block sucrase which converts disaccharides to monosaccharides.
Example: Acarbose
MOA and example of incretin based therapies
GLP-1 agonist increases insulin secretion and blocks glucagon release.
Example: trulicity
DPP-4 Antagonist: DPP-4 enzyme inactivated GLP-1. Inhibition of DPP-4 prolongs GLP-1 activity.
Example: Januvia
MOA and example of Amylin Analog
Decreases glucagon release.
Amylin is released from beta cells
Example: symlin
Exocrine function of pancreas
Pancreatic enzymes breakdown fats and proteins
Endocrine function of pancreas
Pancreatic islet cells: alpha cells and beta cells
Function of islet alpha cells
Glucagon release, stimulated by decreased glucose levels
Function of islet beta cells
Release insulin and c peptide and amylin in response to elevated glucose.
What is unique about c peptide
C peptide holds A chain and B chain of insulin together. It can be used as a marker for endogenous insulin release.
List four main types of diabetes
Type I- insulin dependent
Type II- non-insulin dependent
Type III- other causes of high glucose related to transient release in pancreatic hormone release (pancreatitis/pancreatic cancer, drug tx)
Type IV- gestational
Main s/s of diabetes
Polydipsia, polyuria, polyphagia
Polyol pathway
Take glucose into cell but stores it in the form of sorbitol (sugar alcohol). Sorbitol doesn’t leave cell, it will increase osmotic pressure. This causes water to enter cell until it bursts.
Where is the sorbitol pathway most evident (where it can be seen more commonly)
Eye lens, nerves, RBCs
List the high affinity GLUT transporters
GLUT 1 Brain and RBC. RBC only utilize glucose as energy. Brain prefers glucose but can use fatty acid oxidation.
List low affinity GLUT transporter
GLUT 2: pancreas, liver, kidney and gut. Only active with high levels of glucose.
Primary GLUT transporter in cells
GLUT 4
Endocrine effects of insulin
Decrease glycogenolysis, decrease amino acids and fatty acid metabolism into ketoacids, enhances glucose storage into glycogen.
Insulin receptor
Tyrosine kinase receptor, needs two insulin molecules to activate. Self dimerize. When activated cause GLUT 4 to locate at cell membrane.
Inhibition of insulin secretion
- Insulin operates via negative feedback
- Leptin: secreted when stomach full inhibits insulin secretion
- SNS: epi acts like glucagon
- Chronically high glucose: initially higher insulin but chronically will desensitize insulin receptors
- Drug therapy: phenytoin
