Eicosanoids, NSAIDs, DMARDs Flashcards
What the hell is a DMARD?
Disease Modifying Anti-Rheumatic Drug
What is the precursor of eicosanoids and where is this released from?
Arachidonic acid, released from membrane via phospholipase A2
What do COX1 / COX2 do?
They catalyze the oxygenation and peroxidation of arachidonic acid
Where are COX1 / COX2 expressed?
COX1: expressed constitutively everywhere, especially in stomach and platelets
COX2: inducible form, present in inflammatory tissues but constitutive in kidney / vascular endothelium
Which COX is the major source of prostanoids in inflammation and cancer?
COX2
Which major eicosanoids are vasodilators vs vasoconstrictors?
Vasodilators: PGE2 and PGI2 (prostacyclin)
Vasoconstrictors: TXA2 (thromboxane) - contract SM
Overall, tend to favor causing vasodilation of blood vessels and hypotension
What is the function of prostaglandins in the stomach?
Maintain secretion of mucins and limit pepsin / acid secretion (inhibition of COX1 causes GI distress / ulcer formation)
COX2 is needed to help existing ulcers heal
What is the CNS effect of prostaglandins?
Pyrogenic and sensitizes nerve endings of pain fibers
What does PGE2 do to the uterus?
Causes contraction
What is the most likely explanation of anti-inflammatory effect of COX-inhibitors?
Diminished eicosanoid effects of vasodilation and sensitization of nociceptive nerves
What can be used to treat pulmonary hypertensions?
Prostacyclin and epoprostenol and Iloprost
PGI2 analogs which are vasodilators
What is alprostadil used for?
Maintaining patent ductus arterosus during caridac surgery
What is the first prostanoid used for glaucoma?
Latanoprost - long-acting derivative of PGF2alpha, increased corneal aqueous humor outflow
What are lipoxygenases and generally what do the products do? Do NSAIDs inhibit this?
Family of enzymes catalyzing oxygenation of arachadonic acid to hydroperoxides called “Leukotrienes”.
Products are chemoattractants for immune cells, which play a role in asthma and inflammatory bowel disease
NO-> NSAIDs are just COX inhibitors
What is the mechanism of action of aspirin?
Inhibits COX1 and COX2, but preferentially COX1 by irreversibly acetylating the active site.