Aging Lung: Molecular Drivers and Impact on Respiratory Diseases-A Narrative Clinical Review

Abstract

The aging process significantly impacts lung physiology and is a major risk factor for chronic respiratory diseases, including chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), asthma, and non-IPF interstitial lung fibrosis. This narrative clinical review explores the molecular and biochemical hallmarks of aging, such as oxidative stress, telomere attrition, genomic instability, epigenetic modifications, proteostasis loss, and impaired macroautophagy, and their roles in lung senescence. Central to this process are senescent cells, which, through the senescence-associated secretory phenotype (SASP), contribute to chronic inflammation and tissue dysfunction. The review highlights parallels between lung aging and pathophysiological changes in respiratory diseases, emphasizing the role of cellular senescence in disease onset and progression. Despite promising research into modulating aging pathways with interventions like caloric restriction, mTOR inhibitors, and SIRT1 activators, clinical evidence for efficacy in reversing or preventing age-related lung diseases remains limited. Understanding the interplay between aging-related mechanisms and environmental factors, such as smoking and pollution, is critical for developing targeted therapies. This review underscores the need for future studies focusing on therapeutic strategies to mitigate aging's detrimental effects on lung health and improve outcomes for patients with chronic respiratory conditions.

Keywords: COPD; IPF; aging; asthma; cellular senescence; fibrotic ILD; oxidative stress.

Figure 1

Changes of lung volumes during aging. Abbreviations: ERV—expiratory reserve volume, FRC—functional residual capacity, IRV—inspiratory reserve volume, RV—residual volume, TLC—total lung capacity, VC—vital capacity. Adopted from Janssens et al. [9].

Figure 2

Schematic representation of the different stages of cellular life.

Figure 3

Cell transformation in senescence—the senescence-associated secretory phenotype (SASP).

Figure 4

Possible mechanisms of senescence (simplified).