Altered respiratory microbiota composition and functionality associated with asthma early in life

Abstract

Background The microbiota of the respiratory tract has an important role in maintaining respiratory health. However, little is known on the respiratory microbiota in asthmatic patients among Middle Eastern populations. This study investigated the respiratory microbiota composition and functionality associated with asthma in Emirati subjects. Methods We performed 16S rRNA and ITS2-gene based microbial profiling of 40 expectorated sputum samples from adult and pediatric Emirati individuals averaging 52 and 7 years of age, respectively with or without asthma. Results We report bacterial difference belonging to Bacteroidetes, Firmicutes, Fusobacteria and Proteobacteria phyla between asthmatic and non-asthmatic controls. Similarly, fungal difference belonging to Ascomycota, Basidiomycota phyla and other unclassified fungi. Differential abundance testing among asthmatic individuals with relation to Asthma Control Test show a significant depletion of Penicillium aethiopicum and Alternaria spp., among poorly controlled asthmatics. Moreover, data suggest a significant expansion of Malassezia spp. and other unclassified fungi in the airways of those receiving steroids and leukotriene receptor antagonists’ combination therapy, in contrast to those receiving steroids alone. Functional profiling from 16S data showed marked differences between pediatric asthmatic and non-asthmatic controls, with pediatric asthmatic patients showing an increase in amino acid (p-value < 5.03 × 10− 7), carbohydrate (p-value < 4.76 × 10− 7), and fatty acid degradation (p-value < 6.65 × 10− 7) pathways, whereas non-asthmatic controls are associated with increase in amino acid (p-value < 8.34 × 10− 7), carbohydrate (p-value < 3.65 × 10− 7), and fatty acid (p-value < 2.18 × 10− 6) biosynthesis pathways in concordance with enterotype composition. Conclusions These differences provide an insight into respiratory microbiota composition in Emirati population and its possible role in the development of asthma early in life. This study provides important information that may eventually lead to the development of screening biomarkers to predict early asthma development and novel therapeutic approaches.

Altered Composition of the Oral Microbiota in Depression Among Cigarette Smokers: A Pilot Study

“…The oral microbiome primarily consists of phyla Actinobacteria, Bacteroidetes, Chlamydiae, Firmicutes, Fusobacteria, Proteobacteria, and Spirochaetes that influence oral health. Microbiome alterations due to changes in diet, aging, immune status, and many other factors have been linked to common mental health disorders such as depression and anxiety (2)(3)(4)(5). These factors play a significant role, in addition to smoking, in the microbiota complexity.…”

Malassezia in Inflammatory Bowel Disease: Accomplice of Evoking Tumorigenesis

“…There was a significant positive correlation between Malassezia-specific IgE levels and AD severity (97). Mittermann and colleagues reported that compared with healthy controls, Malassezia was more abundantly detected in sputum specimens of asthmatic patients, particularly in children (98). High detection rates of Malassezia were observed in respiratory tract of CF patients as well (99,100).…”

Chronic Diseases Associated with Malassezia Yeast

“…However, in a 18S rRNA pyrosequencing study of sputum from 30 asthma patients and 13 controls, Malassezia was abundantly detected only in asthma patients with a percentage of reads from 0.01% to 21.65% [54]. Another study based on ITS2 metabarcoding recently reported that Malassezia was very abundant in sputum specimens from 40 asthmatic patients, especially children, with a mean abundance of 67.69%, 27.04%, 2.02% and 2.94% in pediatric asthma, adult asthma, healthy adult and healthy pediatric participants, respectively [55]. In addition, asthmatic patients receiving a combination of steroid and leukotriene receptor antagonists therapy have a significantly increased abundance of Malassezia in their airways.…”