Table 1.

Alterations of Iron metabolism Proteins upon Cigarette smoke Exposure

Iron Parameter	Cell type(s)	Regulated	Disease Relevance	Reference
Intracellular Iron Regulation
Ferritin	Alveolar epithelial cells (AECs)	Increased by cigarette smoke (CS), wood smoke	COPD	[11, 18]
Ferritin	Whole lung, AMs	Increased mRNA in COPD, increased sequestration in AMs increased staining in AMs in IPF	COPD (increased disease severity), IPF (increased pulmonary artery pressure)	[16, 17, 19-23]
IREB2/IRP2	Whole lung, AMs	Increased mRNA in whole lung, decreased in AMs in COPD patients	COPD	[21]
Mitochondrial Iron	Whole lung	Increased by CS	COPD	[30]
Iron Transporters
Divalent metal transporter 1 (DMT1)	AECs	Increased by cigarette smoke (CS), wood smoke	COPD	[18]
Transferrin Receptor (TfR)	Whole	Increased mRNA in whole lung	COPD	[21]
Ferroportin	Whole lung, AMs	Increased mRNA in whole lung, altered in AMs in COPD patients	COPD	[21]
ZIP8	Whole lung	Increased in smokers	Not clear	[64, 65]
Extracellular Iron Transporters/Siderophores/Regulators
Transferrin (Tf)	Whole lung, AMs	Increased mRNA in whole lung, decreased in AMs in COPD patients	COPD	[21]
Lipocalin-2	AMs, AECs	Increased secretion	COPD, lung cancer, cystic fibrosis	[7, 109–115]
Hepcidin	Cellular source?	Pro- form increased in serum of COPD patients; mutation resulting in restrictive disease	COPD, restrictive lung disease	[25, 150]