Epigenetics and sarcoidosis

Our plain-English summary of Epigenetics and sarcoidosis, by I.R. Konigsberg, L.A. Maier, I.V. Yang (European Respiratory Review, 2021).

The study

• Authors: I.R. Konigsberg, L.A. Maier, I.V. Yang
• Journal: European Respiratory Review
• Published: 2021;30(160)
• Type of article: Review
• Cited by: 15 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

Epigenetic modifications are emerging as important regulatory mechanisms of gene expression in lung disease, given that they are influenced by environmental exposures and genetic variants, and that they regulate immune and fibrotic processes. In this review, we introduce these concepts with a focus on the study of DNA methylation and histone modifications and discuss how they have been applied to lung disease, and how they can be applied to sarcoidosis. This information has implications for other exposure and immunologically mediated lung diseases, such as chronic beryllium disease, hypersensitivity pneumonitis, and asbestosis.

Copyright ©The authors 2021.

In plain English

This article was a review, not a new study. The authors explained epigenetics, meaning chemical changes that affect how genes are switched on or off without changing the DNA sequence. They focused on DNA methylation and histone modifications and discussed how these have been studied in lung disease and could be studied in sarcoidosis. They wrote that research on epigenetics in sarcoidosis had so far been limited to microRNA studies, one epigenome-wide study of DNA methylation, and no studies of histone modifications. They described their own group's earlier 2019 study, which compared lung fluid from 9 people with progressive sarcoidosis and 15 whose disease remitted, and found 516 DNA sites near 420 genes associated with progression. The authors noted that most earlier studies were small, and they recommended careful choice of tissue, larger samples and repeated sampling over time. They concluded that epigenomic studies would help link risk factors to disease and sort patients into subgroups. Asbestosis was named once, in the abstract, as a related disease. The article presented no data on asbestos.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: narrative review
• Who was studied: No study population. The authors reviewed published research on epigenetic changes in lung disease, focusing on sarcoidosis.
• Exposure: Environmental exposures were discussed in general terms in relation to sarcoidosis and epigenetics. These included tobacco smoke, air pollution, agricultural work, insecticide, mould/mildew, wood combustion and silica. Asbestos was not studied or discussed in the body of the article. Asbestosis appears only once, in the abstract, as a related disease.
• Main results:
  • According to the authors, epigenetic research in sarcoidosis had been limited to microRNA studies, one epigenome-wide association study of DNA methylation, and no studies of histone modifications.
  • The review described the authors' group's earlier 2019 study, which was cited here and is not new to this review. In lung lavage fluid from 9 progressive and 15 remitting sarcoidosis patients, it found 516 CpG sites near 420 unique genes significantly associated with disease progression (false discovery rate-adjusted p less than 0.05 and more than 5% methylation change).
  • In that earlier study, the authors reported considerable overlap in the direction of methylation changes between sarcoidosis and chronic beryllium disease.
  • The authors stated that most previous -omic studies in sarcoidosis were small, and they recommended longitudinal studies.
• The authors' conclusion: The authors concluded that epigenomic studies would provide a means of linking risk factors to disease biology, understanding disease course, aiding antigen studies and subclassifying patients by molecular profile.

Topics

Medical terms in this study, explained in our Lexicon: Environmental Exposure, Pneumonitis.

Related studies

• Relative release of interleukin-1 beta and interleukin-1 receptor antagonist by alveolar macrophages. A study in asbestos-induced lung disease, sarcoidosis, and idiopathic pulmonary fibrosis — J.N. Kline, D.A. Schwartz, et al. (1993)
• Chitotriosidase activity in sarcoidosis and some other pulmonary diseases — M. Tercelj, B. Salobir, et al. (2009)
• Pulmonary granulomatous reaction: talc pneumoconiosis or chronic sarcoidosis? — P. Tukiainen, J. Nickels, et al. (1984)
• Genetic factors predicting IFN-gamma generation potential in patients with sarcoidosis and after haematopoietic stem cell transplantation — A. Lange (2008)
• Environmental toxicants--induced epigenetic alterations and their reversers — M. Kim, M. Bae, et al. (2012)
• Risk of occupational exposure to asbestos, silicon and arsenic on pulmonary disorders: Understanding the genetic-epigenetic interplay and future prospects — P. Bhattacharjee, S. Paul, et al. (2016)

Browse more research in European Respiratory Review, or return to medical research.