METHODS: Relevant published studies, literature and reports were searched from accessible electronic databases and related institutional databases. We used keywords, viz; microbiome, microbiota, microbiome drug delivery and respiratory disease. Selected articles were carefully read through, clustered, segregated into subtopics and reviewed.
FINDINGS: The traditional belief of sterile lungs was challenged by the emergence of culture-independent molecular techniques and the recently introduced invasive broncho-alveolar lavage (BAL) sampling method. The constitution of a lung microbiome mainly depends on three main ecological factors, which include; firstly, the immigration of microbes into airways, secondly, the removal of microbes from airways and lastly, the regional growth conditions. In healthy conditions, the microbial communities that co-exist in our lungs can build significant pulmonary immunity and could act as a barrier against diseases, whereas, in an adverse way, microbiomes may interact with other pathogenic bacteriomes and viromes, acting as a cofactor in inflammation and host immune responses, which may lead to the progression of a disease. Thus, the use of microbiota as a target, and as a drug delivery system in the possible modification of a disease state, has started to gain massive attention in recent years. Microbiota, owing to its unique characteristics, could serve as a potential drug delivery system, that could be bioengineered to suit the interest. The engineered microbiome-derived therapeutics can be delivered through BC, bacteriophage, bacteria-derived lipid vesicles and microbe-derived extracellular vesicles. This review highlights the relationships between microbiota and different types of respiratory diseases, the importance of microbiota towards human health and diseases, including the role of novel microbiome drug delivery systems in targeting various respiratory diseases.
METHODS: A systematic review on ischemic stroke was carried out for all articles obtained from databases until 22nd October 2020. Main findings were extracted from all the eligible studies.
RESULTS: Eighteen eligible studies were included in the systematic review. These studies suggested that aging, inflammation, and different microbial compositions could contribute to ischemic stroke. Phyla Firmicutes and Bacteroidetes also appeared to manipulate post-stroke outcome. The important role of microbiota-derived short-chain fatty acids and trimethylamine N-oxide in ischemic stroke were also highlighted.
CONCLUSIONS: This is the first systematic review that investigates the relationship between microbiome and ischemic stroke. Aging and inflammation contribute to differential microbial compositions and predispose individuals to ischemic stroke.
METHODS: Oral swab samples were collected from smokers, smokeless tobacco users, and healthy controls (n = 44). Microbial DNA was extracted and the 16S rRNA gene profiled using the Illumina MiSeq platform. Sequencing reads were processed using DADA2, and taxonomical classification was performed using the phylogenetic placement method. Differentially abundant taxa were identified using DESeq2, while functional metagenomes based on KEGG orthology abundance were inferred using LIMMA.
RESULTS: A significantly higher microbial diversity was observed in smokeless tobacco users and smokers relative to controls (P 1.5; BH adj P
RESEARCH DESIGN & METHODS: Here, we present an interesting case of a 22-year-old woman treated with FMT primarily to treat recurrent Clostridioides difficile infection, which coincidentally alleviated her ADHD symptoms. We also present the pre- and post-FMT gut microbiota profiles conducted using shotgun metagenomic sequencing on the patient's fecal samples to thereby highlight potential microbial-associated mechanisms associated with the relief of ADHD symptoms.
RESULTS & CONCLUSIONS: Our case report provides preliminary evidence regarding the use of FMT in a patient with C. difficile and ADHD. We speculate that gut microbiome modulation, in particular the gain or loss of specific microbial species and pathways involving the metabolism of SCFAs, tryptophan and GABA, may merit further exploration as a potential therapeutic strategy for ADHD.
DESIGN: A single-centre cohort study of 155 patients infected with Campylobacter jejuni. Features of the initial illness as well as current bowel symptoms and the intestinal microbiota composition were recorded soon after infection (visit 1, <40 days) as well as 40-60 days and >80 days later (visits 2 and 3). Microbiota were assessed using 16S rRNA sequencing.
RESULTS: PI-BD was found in 22 of the 99 patients who completed the trial. The cases reported significantly looser stools, with more somatic and gastrointestinal symptoms. Microbiota were assessed in 22 cases who had significantly lower diversity and altered microbiota composition compared with the 44 age-matched and sex-matched controls. Moreover 60 days after infection, cases showed a significantly lower abundance of 23 taxa including phylum Firmicutes, particularly in the order Clostridiales and the family Ruminoccocaceae, increased Proteobacteria abundance and increased levels of Fusobacteria and Gammaproteobacteria. The microbiota changes were linked with diet; higher fibre consumption being associated with lower levels of Gammaproteobacteria.
CONCLUSION: The microbiota of PI-BD patients appeared more disturbed by the initial infection compared with the microbiota of those who recovered. The prebiotic effect of high fibre diets may inhibit some of the disturbances seen in PI-BD.
TRIAL REGISTRATION NUMBER: NCT02040922.