UVR	Ultraviolet radiation
ROS	Reactive oxygen species
NADPH	Nicotinamide adenine dinucleotide phosphate
HaCaT	Human epidermal keratinocytes
IL	Interleukin
TNF- α	Tumor necrosis factor α
NF-kB	Nuclear factor kappa light chain enhancer of activated B
HIF-1a	Hypoxia-inducible factor 1-alpha
Nrf-2	Nuclear factor erythroid 2-related factor 2
AP-1	Activator protein 1
SC	Stratum corneum
TEWL	Transepidermal water loss
EGFR	Epidermal growth factor receptor
TGFR	Transforming growth factor receptors
TLRs	Toll-like receptors
TNFR	TNF-α receptor
CSF	Colony stimulating factors
TGF-α	Transforming growth factor α
TGF- β	Transforming growth factor β
HMGB1	High-mobility group box 1
PDGF	Platelet-derived growth factor
COX2	Cyclooxygenases 2
MAP	Mitogen-activated protein
PGE2	Prostaglandin 2
TβRII	TGF-β type II receptor
ECM	Extracellular matrix
HDFs	Human dermal fibroblasts
NHDFs	Normal human dermal fibroblasts
HSF2	Human skin fibroblasts
MED	Minimal erythemal dose
iNOS	Inducible nitric oxide synthase
FGF	Fibroblast growth factors
MMPs	Matrix-degrading metalloproteinases
MMP-1	Collagenase-1
MMP-3	Stromelysin-1
MMP-9	Gelatinase B
COL1A2	Type I collagen gene
SASP	Senescence-associated secretory phenotype