ATRA	All-trans retinoic acid
RAR	Retinoic acid receptor
RXR	Retinoid X receptor
CYP26	Cytochrome P450 family 26 enzymes
RAMBAs	Retinoic acid metabolism blocking agents
RARMs	Retinoic acid receptor modulators
SAR	Structure-activity relationship
ADH	Alcohol dehydrogenase
ALDH	Aldehyde dehydrogenase
RDH	Retinol dehydrogenase
SDR	Short-chain dehydrogenase/reductase
LRAT	Lecithin-retinol acyltransferase
NLC	Nanostructured lipid carrier
PLGA	Poly(lactic-co-glycolic acid)
PEG	Polyethylene glycol
DSP	Digital signal processing
CRABP-II	Cellular retinoic acid-binding protein II
blh	β-carotene 15,15’-oxygenase