PHARMACOLOGIC THERAPY - ANTIDIABETIC AGENTS Flashcards
what is the first line pharmacologic therapy (anti diabetic agents)?
Biguanides (metformin)
what is the function of biguanides (metformin)?
reduce hepatic glucose output and increasing the insulin sensitivity of liver and peripheral tissues
- metformin-only biguanide in Canada
what is the function of incretions?
are released by enteroendocrine cells following a meal an stimulate insulin secretion from pancreatic beta cells and reduce glucagon release from alpha cells
what is the function of DPP-4 inhibitors?
promote activity of incretions by inhibiting the dipeptidyl peptidase-4 enzyme which degrades the main incretions GLP-1 (glucagon-like peptide 1) and glucose dependent insulin tropic polypeptide (or GIP)
what is the function of GLP-1?
receptor agonists that are injectable agents that promote GLP-1 receptor signalling to enhance glucose dependent insulin release from beta cells - slows gastric emptying and reduces apetite
what is the function of SGLT -2 inhibitors?
these inhibitors act to inhibit the renal sodium glucose cotransporter of the proximal convoluted tubule to prevent glucose reabsorption by the kidney
what is the renal sodium glucose cotransporter responsible for?
moves sodium and glucose in a 1 to 1 ratio and is responsible for 90% of renal glucose reabsorption
when should SGLT -2 inhibitors be used with caution?
patients with renal dysfunction, loop diuretics and elderly
- can increase risk of developing UTI
- contradicted in those with reduced GFR
what are the insulin secretagogues? And what do they cause?
sulfanylurea and non-sulfanylurea agents
-cause hypoglycaemia, an patient should be evaluated on how to avoid, recognize and manage hypoglycaemia episodes
what is the function of sulfanylureas?
-acts by binding to sulfanylurea receptor on the beta cell which is linked to ATP sensitive K+ channel
-this causes K+ channel to close and depolarization to occur
-depolarization causes an influx of Ca+ ions and insulin secretion ensues
what is the function of non-sulfanylureas?
-require glucose to be present in order to close the ATP dependent K+ channel of the beta cell
-leads to depolarization of beta cell and subsequent insulin release
what is the function of alpha-glucosidase inhibitors (acarbose)?
-are used when insulin secretagogues or metformin is not effective in decreasing post prandial hyperglycaemia
-it is enzyme that breaks down complex carbs in small intestine
-if enzyme is inhibited, it delays the breakdown of carbs- thus blunting post prandial increase in glucose an insulin levels
does hypo or hyper -glycemia occur when alpha glucoseidase inhibitors are used in conjunction with sulfanylurea agents
HYPOglycemia
what is the function of Thiazoilidinediones?
-target insulin resistance by binding to the nuclear peroxisome proliferator-activated receptor gamma (PPAR gamma) that is highly expressed in adipose tissue an is responsible for changes in adipokines observed in T2D
what changes occur in adipokines observed in T2D?
increased levels of serum leptin, resistin an decreased levels of adiponectin
