Gut bacterial microbiota in patients with myasthenia gravis: results from the MYBIOM study

Background: Myasthenia gravis (MG) is an autoimmune neuromuscular disease, with gut microbiota considered to be a pathogenetic factor. Previous pilot studies have found differences in the gut microbiota of patients with MG and healthy individuals. To determine whether gut microbiota has a pathogenetic role in MG, we compared the gut microbiota of patients with MG with that of patients with non-inflammatory and inflammatory neurological disorders of the peripheral nervous system (primary endpoint) and healthy volunteers (secondary endpoint). Methods: Faecal samples were collected from patients with MG ( n = 41), non-inflammatory neurological disorder (NIND, n = 18), chronic inflammatory demyelinating polyradiculoneuropathy (CIDP, n = 6) and healthy volunteers ( n = 12). DNA was isolated from these samples, and the variable regions of the 16S rRNA gene were sequenced and statistically analysed. Results: No differences were found in alpha- and beta-diversity indices computed between the MG, NIND and CIDP groups, indicating an unaltered bacterial diversity and structure of the microbial community. However, the alpha-diversity indices, namely Shannon, Chao 1 and abundance-based coverage estimators, were significantly reduced between the MG group and healthy volunteers. Deltaproteobacteria and Faecalibacterium were abundant within the faecal microbiota of patients with MG compared with controls with non-inflammatory diseases. Conclusion: Although the overall diversity and structure of the gut microbiota did not differ between the MG, NIND and CIDP groups, the significant difference in the abundance of Deltaproteobacteria and Faecalibacterium supports the possible role of gut microbiota as a contributor to pathogenesis of MG. Further studies are needed to confirm these findings and to develop possible treatment strategies.

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Gut microbiota of endangered crested ibis: Establishment, diversity, and association with reproductive output

PLoS ONE ◽

10.1371/journal.pone.0250075 ◽

2021 ◽

Vol 16 (4) ◽

pp. e0250075

Author(s):

Jian Ran ◽

Qiu-Hong Wan ◽

Sheng-Guo Fang

Keyword(s):

Gut Microbiota ◽

Alpha Diversity ◽

16S Rrna Gene Sequencing ◽

Diversity Indices ◽

Reproductive Capacity ◽

Rrna Gene ◽

Alpha And Beta Diversity ◽

Microbiome Composition ◽

Crested Ibis ◽

Significant Difference

Gut microbiota is known to influence the host’s health; an imbalance of the gut microbial community leads to various intestinal and non-intestinal diseases. Research on gut microbes of endangered birds is vital for their conservation. However, a thorough understanding of the gut microbiome composition present in crested ibises at different ages and its correlation with crested ibis reproductive capacity has remained elusive. Here, we used 16S rRNA gene sequencing to explore the fecal microbial structure of nestlings and adult birds, and the difference in gut microbiota between healthy and sterile crested ibises. We observed that (1) bacterial microbiota, alpha and beta diversity of one-day-old nestlings significantly distinguished from other nestlings; abundance of Proteobacteria decreased, while that of Fusobacteria increased with an increase in the age of the nestlings; (2) there was no significant difference in community composition among adult crested ibises aged one, two, three, and five years; (3) the abundance of Proteobacteria and alpha diversity indices were higher in sterile crested ibises than in healthy crested ibises; thus, Proteobacteria can act as a diagnostic biomarker of reproductive dysfunction in crested ibises. This study significantly contributes to the field of ecology and conservation, as it provides a platform for assessing the reproductive capacity of endangered crested ibises, based on the gut microbiota composition. Further studies may unravel additional factors influencing crested ibises’ reproductive health, which will further help the management and control of the crested ibis population.

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Gut microbiota composition is associated with narcolepsy type 1

Neurology Neuroimmunology & Neuroinflammation ◽

10.1212/nxi.0000000000000896 ◽

2020 ◽

Vol 7 (6) ◽

pp. e896

Author(s):

Alexandre Lecomte ◽

Lucie Barateau ◽

Pedro Pereira ◽

Lars Paulin ◽

Petri Auvinen ◽

...

Keyword(s):

Community Structure ◽

Gut Microbiota ◽

Bacterial Communities ◽

Beta Diversity ◽

Alpha Diversity ◽

Amplicon Sequencing ◽

Rrna Gene ◽

Differential Abundance ◽

Alpha And Beta Diversity

ObjectiveTo test the hypothesis that narcolepsy type 1 (NT1) is related to the gut microbiota, we compared the microbiota bacterial communities of patients with NT1 and control subjects.MethodsThirty-five patients with NT1 (51.43% women, mean age 38.29 ± 19.98 years) and 41 controls (57.14% women, mean age 36.14 ± 12.68 years) were included. Stool samples were collected, and the fecal microbiota bacterial communities were compared between patients and controls using the well-standardized 16S rRNA gene amplicon sequencing approach. We studied alpha and beta diversity and differential abundance analysis between patients and controls, and between subgroups of patients with NT1.ResultsWe found no between-group differences for alpha diversity, but we discovered in NT1 a link with NT1 disease duration. We highlighted differences in the global bacterial community structure as assessed by beta diversity metrics even after adjustments for potential confounders as body mass index (BMI), often increased in NT1. Our results revealed differential abundance of several operational taxonomic units within Bacteroidetes, Bacteroides, and Flavonifractor between patients and controls, but not after adjusting for BMI.ConclusionWe provide evidence of gut microbial community structure alterations in NT1. However, further larger and longitudinal multiomics studies are required to replicate and elucidate the relationship between the gut microbiota, immunity dysregulation and NT1.

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Standardization of Plant Microbiome Studies: Which Proportion of the Microbiota is Really Harvested?

Microorganisms ◽

10.3390/microorganisms8030342 ◽

2020 ◽

Vol 8 (3) ◽

pp. 342 ◽

Cited By ~ 2

Author(s):

Abdoul Razack Sare ◽

Gilles Stouvenakers ◽

Mathilde Eck ◽

Amber Lampens ◽

Sofie Goormachtig ◽

...

Keyword(s):

16S Rrna ◽

Scientific Community ◽

Human Microbiome ◽

Alpha Diversity ◽

Rrna Gene ◽

Alpha And Beta Diversity ◽

Significant Difference ◽

Plant Microbiota ◽

Root Microbiome ◽

Plant Microbiome

Studies in plant-microbiome currently use diverse protocols, making their comparison difficult and biased. Research in human microbiome have faced similar challenges, but the scientific community proposed various recommendations which could also be applied to phytobiome studies. Here, we addressed the isolation of plant microbiota through apple carposphere and lettuce root microbiome. We demonstrated that the fraction of the culturable epiphytic microbiota harvested by a single wash might only represent one-third of the residing microbiota harvested after four successive washes. In addition, we observed important variability between the efficiency of washing protocols (up to 1.6-fold difference for apple and 1.9 for lettuce). QIIME2 analysis of 16S rRNA gene, showed a significant difference of the alpha and beta diversity between protocols in both cases. The abundance of 76 taxa was significantly different between protocols used for apple. In both cases, differences between protocols disappeared when sequences of the four washes were pooled. Hence, pooling the four successive washes increased the alpha diversity for apple in comparison to a single wash. These results underline the interest of repeated washing to leverage abundance of microbial cells harvested from plant epiphytic microbiota whatever the washing protocols, thus minimizing bias.

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Effects of tobacco smoke and electronic cigarette vapor exposure on the oral and gut microbiota in humans: a pilot study

PeerJ ◽

10.7717/peerj.4693 ◽

2018 ◽

Vol 6 ◽

pp. e4693 ◽

Cited By ~ 24

Author(s):

Christopher J. Stewart ◽

Thomas A. Auchtung ◽

Nadim J. Ajami ◽

Kenia Velasquez ◽

Daniel P. Smith ◽

...

Keyword(s):

Pilot Study ◽

Gut Microbiota ◽

Tobacco Smoking ◽

Electronic Cigarettes ◽

Alpha Diversity ◽

Rrna Gene ◽

Cross Sectional ◽

Buccal Swabs ◽

Significant Difference

BackgroundThe use of electronic cigarettes (ECs) has increased drastically over the past five years, primarily as an alternative to smoking tobacco cigarettes. However, the adverse effects of acute and long-term use of ECs on the microbiota have not been explored. In this pilot study, we sought to determine if ECs or tobacco smoking alter the oral and gut microbiota in comparison to non-smoking controls.MethodsWe examined a human cohort consisting of 30 individuals: 10 EC users, 10 tobacco smokers, and 10 controls. We collected cross-sectional fecal, buccal swabs, and saliva samples from each participant. All samples underwent V4 16S rRNA gene sequencing.ResultsTobacco smoking had a significant effect on the bacterial profiles in all sample types when compared to controls, and in feces and buccal swabs when compared to EC users. The most significant associations were found in the gut, with an increased relative abundance ofPrevotella(P= 0.006) and decreasedBacteroides(P= 0.036) in tobacco smokers. The Shannon diversity was also significantly reduced (P= 0.009) in fecal samples collected from tobacco smokers compared to controls. No significant difference was found in the alpha diversity, beta-diversity or taxonomic relative abundances between EC users and controls.DiscussionFrom a microbial ecology perspective, the current pilot data demonstrate that the use of ECs may represent a safer alternative compared to tobacco smoking. However, validation in larger cohorts and greater understanding of the short and long-term impact of EC use on microbiota composition and function is warranted.

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Bioconversion Variation of Ginsenoside CK Mediated by Human Gut Microbiota From Healthy Volunteers and Colorectal Cancer Patients

10.21203/rs.3.rs-181900/v1 ◽

2021 ◽

Author(s):

Yin-Ping Guo ◽

Li Shao ◽

Li Wang ◽

Man-Yun Chen ◽

Wei Zhang ◽

...

Keyword(s):

Colorectal Cancer ◽

16S Rrna ◽

Gut Microbiota ◽

Healthy Volunteers ◽

Healthy Subjects ◽

Positive Association ◽

16S Rrna Gene Sequencing ◽

Rrna Gene ◽

Significant Difference

Abstract Background: Ginsenoside CK (GCK) serves as the potential anti-colorectal cancer (CRC) protopanaxadiol (PPD)-type saponin, which could be mainly bio-converted to yield PPD by gut microbiota. Meanwhile, the anti-CRC effects of GCK could be altered by gut microbiota due to its different diversity in CRC patients. We aimed to investigate the bioconversion variation of GCK mediated by gut microbiota from CRC patients by comparing with healthy subjects.Methods: Gut microbiota profiled by 16S rRNA gene sequencing was collected from healthy volunteers and CRC patients. GCK was incubated with gut microbiota in vitro. A LC-MS/MS method was validated to quantify GCK and PPD after incubation at different time points.Results: The bioconversion of GCK in healthy subjects group was much faster than CRC group, as well as the yield of PPD. Moreover, significant difference of PPD concentration between healthy subjects group and CRC group could be observed at 12 h, 48 h and 72 h check points. According to 16S rRNA sequencing, the profiles of gut microbiota derived from healthy volunteers and CRC patients significantly varied, in which 12 differentially abundant taxon were found, such as Bifidobacterium, Roseburia, Bacteroides and Collinsella. Spearman’s correlation analysis showed bacteria enriched in healthy subjects group were positively associated with biotransformation of GCK, while bacteria enriched in CRC group displayed non correlation characters. Among them, Roseburia which could secrete β-glycosidase showed the strongest positive association with the bioconversion of GCK.Conclusion: The bioconversion of GCK in healthy subjects was much faster than CRC patients mediated by gut microbiota, which might alter the anti-CRC effects of GCK.

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Evaluation of the gut microbiome in association with biological signatures of inflammation in murine polytrauma and shock

Scientific Reports ◽

10.1038/s41598-021-85897-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sandra A. Appiah ◽

Christine L. Foxx ◽

Dominik Langgartner ◽

Annette Palmer ◽

Cristian A. Zambrano ◽

...

Keyword(s):

Gut Microbiota ◽

Community Composition ◽

Gut Microbiome ◽

Beta Diversity ◽

Microbial Community Composition ◽

Alpha Diversity ◽

Global Changes ◽

Rrna Gene ◽

Alpha And Beta Diversity ◽

Increased Risk

AbstractSevere injuries are frequently accompanied by hemorrhagic shock and harbor an increased risk for complications. Local or systemic inflammation after trauma/hemorrhage may lead to a leaky intestinal epithelial barrier and subsequent translocation of gut microbiota, potentially worsening outcomes. To evaluate the extent with which trauma affects the gut microbiota composition, we performed a post hoc analysis of a murine model of polytrauma and hemorrhage. Four hours after injury, organs and plasma samples were collected, and the diversity and composition of the cecal microbiome were evaluated using 16S rRNA gene sequencing. Although cecal microbial alpha diversity and microbial community composition were not found to be different between experimental groups, norepinephrine support in shock animals resulted in increased alpha diversity, as indicated by higher numbers of distinct microbial features. We observed that the concentrations of proinflammatory mediators in plasma and intestinal tissue were associated with measures of microbial alpha and beta diversity and the presence of specific microbial drivers of inflammation, suggesting that the composition of the gut microbiome at the time of trauma, or shortly after trauma exposure, may play an important role in determining physiological outcomes. In conclusion, we found associations between measures of gut microbial alpha and beta diversity and the severity of systemic and local gut inflammation. Furthermore, our data suggest that four hours following injury is too early for development of global changes in the alpha diversity or community composition of the intestinal microbiome. Future investigations with increased temporal-spatial resolution are needed in order to fully elucidate the effects of trauma and shock on the gut microbiome, biological signatures of inflammation, and proximal and distal outcomes.

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Age-Related Differences in the Gut Microbiome of Rhesus Macaques

The Journals of Gerontology Series A ◽

10.1093/gerona/glaa048 ◽

2020 ◽

Vol 75 (7) ◽

pp. 1293-1298 ◽

Cited By ~ 4

Author(s):

Julie Adriansjach ◽

Scott T Baum ◽

Elliot J Lefkowitz ◽

William J Van Der Pol ◽

Thomas W Buford ◽

...

Keyword(s):

Sex Differences ◽

Gut Microbiota ◽

Relative Abundance ◽

Rhesus Macaques ◽

Alpha Diversity ◽

Multiple Comparisons ◽

Rrna Gene ◽

Alpha And Beta Diversity ◽

Age Related ◽

The Impact

Abstract Aging is a multifactorial process characterized by progressive changes in gut physiology and the intestinal mucosal immune system. These changes, along with alterations in lifestyle, diet, nutrition, inflammation and immune function alter both composition and stability of the gut microbiota. Given the impact of environmental influences on the gut microbiota, animal models are particularly useful in this field. To understand the relationship between the gut microbiota and aging in nonhuman primates, we collected fecal samples from 20 male and 20 female rhesus macaques (Macaca mulatta), across the natural macaque age range, for 16S rRNA gene analyses. Operational taxonomic units were then grouped together to summarize taxon abundance at different hierarchical levels of classification and alpha- and beta-diversity were calculated. There were no age or sex differences in alpha diversity. At the phylum level, relative abundance of Proteobacteria and Firmicutes and Firmicutes to Bacteriodetes ratio were different between age groups though significance disappeared after correction for multiple comparisons. At the class level, relative abundance of Firmicutes_Bacilli decreased and Proteobacteria_Alphaproteobacteria and Proteobacteria_Betaproteobacteria increased with each successively older group. Only differences in Firmicutes_Bacilli remained significant after correction for multiple comparisons. No sex differences were identified in relative abundances after correction for multiple comparisons. Our results are not surprising given the known impact of environmental factors on the gut microbiota.

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Influence of Host Plants on the Diversity of Gut Microbiota Communities of Fall Armyworm Spodoptera frugiperda J.E. Smith (Lepidoptera: Noctuidae)

10.21203/rs.3.rs-657579/v1 ◽

2021 ◽

Author(s):

Juliana Amaka Ugwu ◽

Fred Asiegbu

Keyword(s):

Gut Microbiota ◽

Sweet Potato ◽

Spodoptera Frugiperda ◽

Sugar Cane ◽

Host Plants ◽

Hypervariable Region ◽

Alpha Diversity ◽

Diversity Indices ◽

Rrna Gene ◽

Linear Discriminant

Abstract The gut bacteria of insects influence their host physiology positively, although their mechanism is not yet understood. This study characterized the microbiome of the gut of Spodoptera frugiperda larvae fed with nine different host plants; sugar cane (M1), maize (M2), onion (M3), cucumber (R1), tomato (R2), sweet potato (R3), cabbage L1), green amaranth (L2), and celocia (L3) by sequencing the theV3-V4 hypervariable region of the 16S rRNA gene using Illumina PE250 NovaSeq system. The results revealed that gut bacterial composition varied among larvae samples fed on different host plants. Three alpha diversity indices revealed highly significant differences on the gut bacterial diversity of S. frugiperda fed with different host plants.. Analysis of Molecular Variance (AMOVA) and Analysis of Similarity (ANOSIM) also revealed significant variations on the bacterial communities among the various host plants. Five bacteria phyla (Firmicutes, Proteobacteria, Cyanobacteria, Actinobacteria and Bacteroidetes) were prevalent across the larvae samples. Firmicutes (44.1%) was the most dominant phylum followed by Proteobacteria (28.5%). Linear discriminant analysis effect size (LEfSe) analyses showed that S. frugiperda larvae were enriched by diverse bacteria groups. Celocia (L3) and sweet potato (R3) were enriched in phylum Firmicutes by 15.1% and 14.2 % respectively while green amaranth (L2) and sugar cane (M1) were enriched in proteobacteria by 18.5% and 14.3% respectively. Genus Enterococcus was predominant and mostly enhanced by L3 with 21.7% incidence. Mann-Whitney’ test revealed highly significant differences (p<0.001) on OTUs number among larvae samples. Our findings indicate that host plant is a major driver shaping insect gut microbiota.

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Diversity, Composition and Functional Inference of Gut Microbiota in Indian Cabbage white Pieris canidia (Lepidoptera: Pieridae)

Life ◽

10.3390/life10110254 ◽

2020 ◽

Vol 10 (11) ◽

pp. 254

Author(s):

Ying Wang ◽

Jianqing Zhu ◽

Jie Fang ◽

Li Shen ◽

Shuojia Ma ◽

...

Keyword(s):

Gut Microbiota ◽

16S Rrna Gene Sequencing ◽

Adult Survival ◽

Rrna Gene ◽

Life Stages ◽

Microbial Composition ◽

Significant Difference ◽

Functional Inference ◽

Rrna Gene Sequencing ◽

Insect Fitness

We characterized the gut microbial composition and relative abundance of gut bacteria in the larvae and adults of Pieris canidia by 16S rRNA gene sequencing. The gut microbiota structure was similar across the life stages and sexes. The comparative functional analysis on P. canidia bacterial communities with PICRUSt showed the enrichment of several pathways including those for energy metabolism, immune system, digestive system, xenobiotics biodegradation, transport, cell growth and death. The parameters often used as a proxy of insect fitness (development time, pupation rate, emergence rate, adult survival rate and weight of 5th instars larvae) showed a significant difference between treatment group and untreated group and point to potential fitness advantages with the gut microbiomes in P. canidia. These data provide an overall view of the bacterial community across the life stages and sexes in P. canidia.

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Multiple bacteria associated with the more dysbiotic genitourinary microbiomes in patients with type 2 diabetes mellitus

Scientific Reports ◽

10.1038/s41598-021-81507-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hua Zha ◽

Fengping Liu ◽

Zongxin Ling ◽

Kevin Chang ◽

Jiezuan Yang ◽

...

Keyword(s):

Diabetes Mellitus ◽

Type 2 Diabetes ◽

Type 2 Diabetes Mellitus ◽

Alpha Diversity ◽

Amplicon Sequencing ◽

Diversity Indices ◽

Vital Role ◽

Rrna Gene ◽

Beta Glucosidase

AbstractType 2 diabetes mellitus (T2DM) influences the human health and can cause significant illnesses. The genitourinary microbiome profiles in the T2DM patients remain poorly understood. In the current study, a series of bioinformatic and statistical analyses were carried out to determine the multiple bacteria associated with the more dysbiotic genitourinary microbiomes (i.e., those with lower dysbiosis ratio) in T2DM patients, which were sequenced by Illumina-based 16S rRNA gene amplicon sequencing. All the genitourinary microbiomes from 70 patients with T2DM were clustered into three clusters of microbiome profiles, i.e., Cluster_1_T2DM, Cluster_2_T2DM and Cluster_3_T2DM, with Cluster_3_T2DM at the most dysbiotic genitourinary microbial status. The three clustered T2DM microbiomes were determined with different levels of alpha diversity indices, and driven by distinct urinalysis variables. OTU12_Clostridiales and OTU28_Oscillospira were likely to drive the T2DM microbiomes to more dysbiotic status, while OTU34_Finegoldia could play a vital role in maintaining the least dysbiotic T2DM microbiome (i.e., Cluster_1_T2DM). The functional metabolites K08300_ribonuclease E, K01223_6-phospho-beta-glucosidase and K00029_malate dehydrogenase (oxaloacetate-decarboxylating) (NADP+) were most associated with Cluster_1_T2DM, Cluster_2_T2DM and Cluster_3_T2DM, respectively. The characteristics and multiple bacteria associated with the more dysbiotic genitourinary microbiomes in T2DM patients may help with the better diagnosis and management of genitourinary dysbiosis in T2DM patients.

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