Gene promoter methylation is associated with lung function in the elderly: the Normative Aging Study

Area of Science:

• Epigenetics
• Pulmonology
• Immunology

Background:

• Lung function decline is a significant mortality predictor.
• Inflammatory pathways are implicated in lung function decrease, but mechanisms remain unclear.
• Epigenetic modifications, such as DNA methylation, may play a role in lung function decline.

Purpose of the Study:

• To investigate the association between DNA methylation in nine inflammatory genes and lung function.
• To explore the role of epigenetic changes in the mechanisms of lung function decline.

Main Methods:

• Cross-sectional study of 756 elderly men in Boston.
• DNA methylation analysis from blood samples.
• Spirometry measurements (Forced Vital Capacity and Forced Expiratory Volume in one second) conducted every 3-5 years from 1999-2006.
• Multivariate mixed-effects regression models used to assess associations.

Main Results:

• Decreased DNA methylation in CRAT, F3, and TLR2 genes was significantly associated with lower lung function (FVC and FEV1).
• Decreased DNA methylation in IFNγ and IL6 genes was significantly associated with better lung function (FEV1).
• Specific quantitative associations were provided for the impact of one IQR decrease in methylation on lung function parameters.

Conclusions:

• DNA methylation is implicated in the biological processes underlying lung function decline.
• IFNγ and IL6 may exhibit ambivalent roles in lung function through negative feedback mechanisms.
• These findings highlight potential epigenetic targets for understanding and potentially intervening in lung function changes.