Effect of indoor environment on microbiota balance

The human gut is home to millions of microorganisms, mostly bacteria, which have positive and negative effects on health.Recent Environmental research A journal paper evaluated how the indoor microbiome and metabolites influence the human gut microbiome.

study: Effects of environmental characteristics on children’s gut microbiota – a pilot study to assess the role of the indoor microbiome and metabolites. Image credit: CI Photos / Shutterstock

Background

Gut microbiota abnormalities are associated with the incidence of many diseases, such as colorectal cancer, inflammatory skin disease, and chronic kidney disease. Several indices, such as the Shannon Index, Simpson Index, Gut Microbiome Health Index (GMHI), and Faith’s PD, have been developed to examine gut health by measuring microbial diversity and abundance. increase.

Several studies have shown that the surrounding environment and personal lifestyle have a significant impact on the gut microbiota. Interestingly, changes in the abundance of gut microbiota taxa in children exposed to pets and increased gut microbial diversity in children exposed to house dust and soil were noted. I’m here. People living near lush areas have enhanced alpha-diversity in the human gut. In contrast, people living in areas with high air pollution levels are at increased risk of gut microbiota abnormalities that affect metabolic health.

Previous studies have shown links between the indoor microbiome and microbial metabolites and chronic diseases such as rhinitis, asthma, sick building syndrome, and dermatitis.Common indoor microbiome Corinthella Aspergillus subversicolor, and Cutibacterium It is believed to be associated with the development of many chronic diseases. However, not all indoor microbes are harmful. for example, Inactive lactic acid bacteria, Prevotella and Dorosi Granuram The indoor environment has a negative impact on the incidence of rhinitis. Additionally, some indoor microbiomes (e.g. Clostridium difficile) also modulates the human gut microbiota.

Diet plays an important role in the number and abundance of gut microbes. A fiber-rich diet favors beneficial bacteria, while a high-fat diet increases levels of harmful bacteria, promotes intestinal inflammation, and alters intestinal permeability. Further research is needed to understand the effects of the indoor microbiome and metabolites on gut microbiota composition and diversity.

About research

This pilot study evaluated the effects of the indoor microbiome and metabolites on the human gut microbiome. A total of 56 children aged 3 to her 10 years were recruited for this study. An electronic questionnaire was used to collect health information and relevant environmental characteristics. A distance-weighted method was used to estimate annual outdoor air pollutants.

Fecal samples were collected from participants and dust samples were collected using a sterile sampler. DNA was extracted from dust samples and analyzed using a culture-independent shotgun metagenomic sequencing technique. Additionally, liquid chromatography-mass spectrometry (LC-MS) was used for chemical profiling of dust samples.

The associations between environmental microbial and non-microbial traits and gut microbiota diversity/composition were investigated using PERMANOVA and regression models. In addition, we investigated the effect of environmental properties on GMHI.

research result

Children recruited in this study were randomly selected from 12 of 16 districts in Shanghai, China. The study cohort consisted of 38% males and 62% females. More than half of the cohort had siblings, and approximately 59% of the children had pets or indoor plants in early childhood. Twenty-one children lived in areas with high traffic. Some children started attending kindergarten. Approximately 16% of children were exposed to environmental tobacco smoking during early childhood.

A total of 6,247 microorganisms were characterized from indoor dust samples. The majority of microorganisms belonged to the classes Bacillus, Gammaproteobacteria and Actinomycetes, followed by Bacteroidia, Flavobacteria, Alphaproteobacteria, Betaproteobacteria, Clostridium and Tissiereria. Some of the most abundantly discovered microbial species include: Acne bacteria, Staphylococcus aureus, Staphylococcus epidermidisand staphylococcus.

Facultative pathogens, etc. Pseudomonas aeruginosa, Mycobacterium tuberculosis, and Klebsiella pneumoniae, was also detected. The virulence factor (VF) and antimicrobial resistance gene (ARG) were determined using molecular sequencing techniques. VF was primarily derived from facultative pathogens.

A total of 1,442 metabolites and chemicals were characterized by mass spectrometry second stage (MS2). Metabolites, mainly lipids (fatty acyl, flavonoid, steroid derivatives, etc.), xenobiotics, amino acids, carbohydrates, cofactors and vitamins were identified during chemical profiling.

A total of 318 bacteria belonging to the phyla Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes were characterized from intestinal samples. Children’s intestinal environment became rich, Flavoni Fractor Plutoi, Ocillibacter, Faecalibacterium. A child’s age and when he or she started kindergarten had a significant impact on gut microbial composition. In addition, living near high-traffic areas also affected gut microbial composition.

Among dietary characteristics, the frequency of soft drinks had a significant effect on the gut microbial composition. Indoor abundance of metabolites and chemicals did not affect overall gut microbial composition.

Conclusion

The authors claim that this study is the first to examine associations between the indoor microbiome/metabolites and the gut microbiota. This study has revealed how exposure to indoor microbes affects the human gut microbiota.