Characterization of gut microbiome and metabolome in Helicobacter pylori patients in an underprivileged community in the United States

BACKGROUND Helicobacter pylori(H.pylori),a bacterium that infects approximately half of the world’s population,is associated with various gastrointestinal diseases,including peptic ulcers,non-ulcer dyspepsia,gastric adenocarcinoma,and gastric lymphoma.As the burden of antibiotic resistance increases,the need for new adjunct therapies designed to facilitate H.pylori eradication and reduce negative distal outcomes associated with infection has become more pressing.Characterization of the interactions between H.pylori,the fecal microbiome,and fecal fatty acid metabolism,as well as the mechanisms underlying these interactions,may offer new therapeutic approaches.AIM To characterize the gut microbiome and metabolome in H.pylori patients in a socioeconomically challenged and underprivileged inner-city community.METHODS Stool samples from 19 H.pylori patients and 16 control subjects were analyzed.16S rRNA gene sequencing was performed on normalized pooled amplicons using the Illumina MiSeq System using a MiSeq reagent kit v2.Alpha and beta diversity analyses were performed in QIIME 2.Non-targeted fatty acid analysis of the samples was carried out using gas chromatography-mass spectrometry,which measures the total content of 30 fatty acids in stool after conversion into their corresponding fatty acid methyl esters.Multi-dimensional scaling(MDS)was performed on Bray-Curtis distance matrices created from both the metabolomics and microbiome datasets and a Procrustes test was performed on the metabolomics and microbiome MDS coordinates.RESULTS Fecal microbiome analysis showed that alpha diversity was lowest in H.pylori patients over 40 years of age compared to control subjects of similar age group.Beta diversity analysis of the samples revealed significant differences in microbial community structure between H.pylori patients and control subjects across all ages.Thirty-eight and six taxa had lower and higher relative abundance in H.pylori patients,respectively.Taxa that were enriched in H.pylori patients included Atopobium,Gemellaceae,Micrococcaceae,Gemellales and Rothia(R.mucilaginosa).Notably,relative abundance of the phylum Verrucomicrobia was decreased in H.pylori patients compared to control subjects.Procrustes analysis showed a significant relationship between the microbiome and metabolome datasets.Stool samples from H.pylori patients showed increases in several fatty acids including the polyunsaturated fatty acids(PUFAs)22:4n6,22:5n3,20:3n6 and 22:2n6,while decreases were noted in other fatty acids including the PUFA 18:3n6.The pattern of changes in fatty acid concentration correlated to the Bacteroidetes:Firmicutes ratio determined by 16S rRNA gene analysis.CONCLUSION This exploratory study demonstrates H.pylori-associated changes to the fecal microbiome and fecal fatty acid metabolism.Such changes may have implications for improving eradication rates and minimizing associated negative distal outcomes.

Intensity-specific considerations for exercise for patients with inflammatory bowel disease

The rising prevalence of inflammatory bowel disease(IBD)necessitates that patients be given increased access to costeffective interventions to manage the disease.Exercise is a non-pharmacologic intervention that advantageously affects clinical aspects of IBD,including disease activity,immune competency,inflammation,quality of life,fatigue,and psychological factors.It is well established that exercise performed at low-to-moderate intensity across different modalities manifests many of these diseased-related benefits while also ensuring patient safety.Much less is known about higher-intensity exercise.The aim of this review is to summarize findings on the relationship between strenuous exercise and IBD-related outcomes.In healthy adults,prolonged strenuous exercise may unfavorably alter a variety of gastrointestinal(GI)parameters including permeability,blood flow,motility,and neuro-endocrine changes.These intensity-and gut-specific changes are hypothesized to worsen IBD-related clinical presentations such as diarrhea,GI bleeding,and colonic inflammation.Despite this,there also exists the evidence that higher-intensity exercise may positively influence microbiome as well as alter the inflammatory and immunomodulatory changes seen with IBD.Our findings recognize that safety for IBD patients doing prolonged strenuous exercise is no more compromised than those doing lower-intensity work.Safety with prolonged,strenuous exercise may be achieved with adjustments including adequate hydration,nutrition,drug avoidance,and careful attention to patient history and symptomatology.Future work is needed to better understand this intensity-dependent relationship so that guidelines can be created for IBD patients wishing to participate in high-intensity exercise or sport.