Steroids Workshop Flashcards
how do glucocorticoids work?
water insoluble, hydrophobic and lipophilic
present in blood bound to proteins (albumin etc)
exposed to all body cells
bind to the glucocorticoid receptor
GR translocates to the nucleus, then binds to DNA and can inhibit transcription of inflammatory genes
GRE?
glucocorticoid recognition element
in what 2 ways can glucocorticoid receptor bind to DNA and what effect does each have?
two receptors bind as a dimer
= increases transcription
one receptor binds as a monomer
= inhibits transcription
what is glucocorticoid response element?
specific sequence of DNA in the promotor which dictates whether target gene transcription in activated or inhibited
what are the types of GRE and what do they do?
+GRE sequence
= favours binding of Glucocorticoid dimer and therefore activation of gene transcription
nGRE sequence
= favours binding of monomer GR and therefore target gene expression is inhibited
all cells in the body are susceptible to steroid action, true or false?
true
as all cells have the GRE present at all times
what other actions can steroid bound GR have?
can tether other transcription factors
- GR monomer or dimer blocks NF kappa B
glucocorticoids only activate the glucocorticoid receptor, true or false?
false
can activate the mineralocorticoid receptor
name a mineralocorticoid
aldosterone
what effect can administration of mineralocorticoid alongside glucocorticoid?
can reduce the side effects of delayed wound healing and skin atrophy seen in glucocorticoid therapy
how do mineralocorticoids have this effect on glucocorticoid side effects?
bind to the mineralocorticoid receptor so the glucocorticoids cant bind and cause the side effects
how is glucocorticoid receptor related to alcohol craving?
the GR is activated in the brain region related to reward
blocking the GR therefore can reduce alcohol cravings and improve liver function as such
