AMP	adenosine monophosphate
ANOVA	analysis of variance
CT	Cholera toxin
DMEM	Dulbecco’s modified Eagle’s medium
DUSP	Dual specific phosphatase
EGF	Epidermal growth factor
ERK	Extracellular signal-regulated protein kinase
FBS	Fetal bovine serum
GSK3β	Glycogen synthase kinase 3β
HKGS	Human keratinocyte growth supplement
JNK	C-Jun N-terminal kinase
l-DOPA	l-3,4-dihydroxyphenylalanine
LPS	Lipopolysaccharide
MAP	Mitogen-activated protein
MITF	Microphthalmia-associated transcription factor
OD	Optical density
PBS	Phosphate-buffered saline
PDRN	Polydeoxyribonucleotide
PG	prostaglandin
PIH	Post-inflammatory hyperpigmentation
PI3K	Phosphatidylinositide 3-kinase
PMP	Photoaging-associated mottled pigmentation
PTU	N’-phenylthiourea
TNF	Tumor necrosis factor
TPA	Phorbol 12-myristate 13-acetate
TRP	Tyrosinase-related protein
UV	Ultraviolet
VEGF	Vascular endothelial growth factor