APF	Aminophenyl fluorescein
ARE	Antioxidant response element
BALF	Bronchoalveolar lavage fluid
BSA	Bovine serum albumin
COPD	Chronic obstructive pulmonary disease
CSE	Cigarette smoke extract
DAB	3,3′-Diaminobenzidine
DCF	Dichlorofluorescein
DMF	Dimethyl fumarate
DNA	Deoxyribonucleic acid
FBS	Fetal bovine serum
GSTA2	Glutathione S-transferase A2
H&E	Hematoxylin and eosin
HBSS	Hanks’ balanced salt solution
HO-1	Heme oxygenase-1
Keap1	Kelch-like ECH-associated protein 1
LDH	Lactate dehydrogenase
Lm	Mean linear intercept
MDA	Malondialdehyde
MMF	Monomethyl fumarate
MMP-9	Matrix metalloproteinase 9
MTT	3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide
NAD+	Nicotinamide adenine dinucleotide (oxidized form)
NADH	Nicotinamide adenine dinucleotide (reduced form)
NF-κB	Nuclear factor kappa B
NQO1	NAD(P)H quinone dehydrogenase 1
Nrf2	Nuclear factor erythroid 2–related factor 2
PBS	Phosphate-buffered saline
PNK	Nitrotyrosine
PPE	Porcine pancreatic elastase
RPMI	Roswell Park Memorial Institute medium
ROS	Reactive oxygen species
RSN	Reactive species of nitrogen
SOD1	Superoxide dismutase 1
TBARS	Thiobarbituric acid reactive substances
TBS	Tris-buffered saline
Vv	Volume density