Iron laden macrophages in idiopathic pulmonary fibrosis: the telltale of occult alveolar hemorrhage?
Abstract
Rationale A number of observations suggest that iron accumulates in the lungs of patients with idiopathic pulmonary fibrosis (IPF) with vascular abnormalities, including pulmonary hypertension.Objectives The aim of this study was to determine the prevalence and intensity of accumulation of alveolar epithelial lining fluid (ELF) iron and of alveolar macrophage hemosiderin in IPF and its relationship with disease severity.Methods Forty seven IPF patients and 14 healthy controls were retrospectively evaluated for iron accumulation in the lower respiratory tract using total iron spectrophotometric measures and for hemosiderin accumulation using the Perls' stain with the Golde score.Measurements and main results Total iron levels in ELF were significantly increased in IPF patients compared to non-smoking controls (p < 0.05); there were no differences with healthy smokers (p = 0.2). Hemosiderin accumulation in alveolar macrophages was similar in never smoking and ever smoking IPF patients (p = 0.5), was significantly higher in IPF patients than in both smoking and non-smoking healthy controls (p < 0.05, all comparisons) and was positively correlated with echocardiographic estimates of pulmonary artery systolic pressure (p < 0.05) and with increasing disease severity scores (p < 0.05).Conclusions The data show exaggerated accumulation of iron in IPF broncho-alveolar ELF and alveolar cells with no association with tobacco smoke, thus suggesting, occult pulmonary hemorrhage as a likely cause.
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Conceivably, senescent cells account for the increased iron observed in aged tissues and in organs affected by age-related pathologies.
“Conceivably, senescent cells account for the increased iron observed in aged tissues [11], [12] and similarly in organs affected by age-related pathologies [13], [14], [15].”
From Iron accumulation in senescent cells is coupled with impaired ferritinophagy and inhibition of ferroptosis (2018) · cites this paper as [13]
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- Authors
- Puxeddu, E., Comandini, A., Cavalli, F., Pezzuto, G., D'Ambrosio, C., Senis, L., Paci, M., Curradi, G., Sergiacomi, G. L., & Saltini, C.
- Affiliations
- Policlinico Tor Vergata (IT)
- University of Rome Tor Vergata (IT)
- University of Bologna (IT)
- Corresponding author
- Saltini, Cesare
- Venue
- Pulmonary Pharmacology & Therapeutics
- Publisher
- Elsevier BV
- Published
- 2014-06
- Volume
- 28
- Issue
- 1
- Pages
- 35-40
- ISSN
- 1094-5539 (ISSN-L)
- OpenAlex
- W2097974689
- Cited by
- 57
- References
- 61
- Citations by year
- 2026: 5 · 2025: 8 · 2024: 5 · 2023: 4 · 2022: 2 · 2021: 9 · 2020: 6 · 2019: 5 · 2018: 4 · 2017: 6 · 2015: 1 · 2014: 2
- FWCI
- 0.81
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Pulmonary Pharmacology & Therapeutics (publishedVersion)
- PubMed (publishedVersion)
- Cineca Institutional Research Information System (Tor Vergata University) (submittedVersion)
- Funders
- Boehringer-Ingelheim
- Topics
- Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Interstitial Lung Diseases and Idiopathic Pulmonary Fibrosis
- Health Sciences › Medicine › Hematology › Iron Metabolism and Disorders
- Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Occupational and environmental lung diseases
- Keywords
- idiopathic pulmonary fibrosis, iron accumulation, alveolar macrophages, hemosiderin, pulmonary hypertension, disease severity, smoking
- MeSH terms
- Adult, Aged, Female, Hemorrhage, Hemosiderin, Humans, Iron, Male, Middle Aged, Pulmonary Alveoli, Retrospective Studies, Severity of Illness Index, Smoking, Spectrophotometry, Case-Control Studies, Macrophages, Alveolar, Idiopathic Pulmonary Fibrosis
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