Role of the Microbiome in Interstitial Lung Diseases

Abstract

There are trillions of microorganisms in the human body, consisting of bacteria, viruses, fungi, and archaea; these collectively make up the microbiome. Recent studies suggest that the microbiome may serve as a biomarker for disease, a therapeutic target, or provide an explanation for pathophysiology in lung diseases. Studies describing the impact of the microorganisms found in the respiratory tract on lung health have been published and are discussed here in the context of interstitial lung diseases. Additionally, epidemiological and experimental evidence highlights the importance of cross-talk between the gut microbiota and the lungs, called the gut–lung axis. The gut-lung axis postulates that alterations in gut microbial communities may have a profound effect on lung disease. Dysbiosis in the microbial community of the gut is linked with changes in immune responses, homeostasis in the airways, and inflammatory conditions in the gastrointestinal tract itself. In this review, we summarize studies describing the role of the microbiome in interstitial lung disease and discuss the implications of these findings on the diagnosis and treatment of these diseases. This paper describes the impact of the microbial communities on the pathogenesis of lung diseases by assessing recent original research and identifying remaining gaps in knowledge.

Change of Intestinal Microbiota in Mice Model of Bronchopulmonary Dysplasia

“…Thus, there is a close interaction between respiratory and intestinal diseases [17,18], which is de ned as gut-lung axis. To our best knowledge, the micro ora in gut and lung are rather complicated, which play important roles in the pathogenesis of pulmonary and intestinal diseases through the gut-lung axis [19][20][21]. In previous studies, disturbance of microorganism was closely associated with the progression and prognosis of lung cancer [22,23].…”

Humidifier Disinfectant Consumption and Humidifier Disinfectant-Associated Lung Injury in South Korea: A Nationwide Population-Based Study

“…In addition, a study of human alveolar epithelial cells showed that exposure to PHMG and PGH elevates the level of the epithelial–mesenchymal transition (EMT)-related protein, an indicator of fibrotic response [ 10 ]. Additionally, there is a possibility for the role of microbiome advances in lung injuries and idiopathic pulmonary fibrosis (IPF), which may potentially link to the environmental exposures [ 26 , 27 , 28 ]. Taken together, it seems plausible that HD-induced inflammation and mRNA expression of fibronectin might trigger a wound-healing response, causing epithelial cells to be stiff and thickened, eventually leading to pulmonary fibrosis, which is identical to the features of HDLI cases.…”

Nutritional Status and the Critically Ill Patient: Gut Microbiota and Immuno-Nutrition in I.C.U. at the Time of SARS-COV 2 Pandemic

“…Over the notable and wide evidences on gut microbiota, lung has its own "microbiota" [57]. While in the gut Bacteroidetes and Firmicutes are predominant, Bacteroidetes, Firmicutes and Proteobacteria are the most represented in the lung [58].…”

“…The "gut-lung axis" is a pathophysiological bidirectional model involved in the pathogenesis of several pulmonary diseases. Specifically, endotoxins (e.g., bacterial lypopolisaccharide (LPS)), microbial metabolites of gut origin can reach the lung through the bloodstream, bringing to the inflammation of the lung tissues and, in a circle, back to the intestine [58]. Thus, it is conceivable that the novel SARS-Cov2 might affect the gut microbiota such as in other interstitial and non-interstitial lung diseases [59].…”

“…By blocking this interleukin, autophagy mediated by endoplasmic reticulum stress and inflammation can be prevented [69]. Interestingly, Bifdobacterium strains are able to inhibit interleukin-17 [58]. Thus, administration of high doses of Bifdobacterium strains (e.g., B. animalis subsp.…”