Imbalances in faecal and duodenal Bifidobacterium species composition in active and non-active coeliac disease

<p>Abstract</p> <p>Background</p> <p>Gut bifidobacteria are believed to influence immune-related diseases. The objective of this study was to assess the possible relationships between the gut bifidobacteria composition and coeliac disease (CD) in children.</p> <p>A total of 48 faecal samples (30 and 18 samples from active and no active CD patients, respectively) and 33 duodenal biopsy specimens of CD patients (25 and 8 samples from active and non-active CD patients, respectively) were analysed. Samples (30 faecal samples and 8 biopsies) from a control age-matched group of children were also included for comparative purposes. Gut <it>Bifidobacterium </it>genus and species were analyzed by real-time PCR.</p> <p>Results</p> <p>Active and non-active CD patients showed lower numbers of total <it>Bifidobacterium </it>and <it>B. longum </it>species in faeces and duodenal biopsies than controls, and these differences were particularly remarkable between active CD patients and controls. <it>B. catenulatum </it>prevalence was higher in biopsies of controls than in those of active and non-active CD patients, whereas <it>B. dentium </it>prevalence was higher in faeces of non-active CD patients than in controls. Correlations between levels of <it>Bifidobacterium </it>and <it>B. longum </it>species in faecal and biopsy samples were detected in both CD patients and controls.</p> <p>Conclusion</p> <p>Reductions in total <it>Bifidobacterium </it>and <it>B. longum </it>populations were associated with both active and non-active CD when compared to controls. These bacterial groups could constitute novel targets for adjuvant dietary therapies although the confirmation of this hypothesis would require further investigations.</p

Breast Milk Microbiota Is Shaped by Mode of Delivery and Intrapartum Antibiotic Exposure

The mode of delivery has been suggested to modulate the bacterial composition of breast milk but the impact of intrapartum antibiotic use on the milk microbiota is currently not known. The aim of this study was to analyze the effects of the mode of the delivery and intrapartum antibiotic administration on the microbial composition of breast milk. Breast milk samples were collected from 84 healthy mothers 1 month after the delivery. In total, 61 mothers had delivered vaginally, 23 of which had received intrapartum antibiotics, 13 women had delivered with non-elective cesarean section, 7 of which had received antibiotics, and 10 mothers had delivered with elective cesarean section without intrapartum antibiotic treatment. Both mode of delivery and intrapartum antibiotic exposure were significantly associated with changes in the milk microbial composition as assessed by analysis of similarities (ANOSIM) test (p = 0.001). The mode of delivery had a more profound effect on the milk microbiota composition as compared to intrapartum antibiotic exposure. Although the clinical significance of breast milk microbiota is currently poorly understood, this study shows that cesarean section delivery has an independent effect on breast milk microbiota composition. The dysbiosis observed in infants born by cesarean section delivery may be aggravated by the aberrant breast milk microbiota

Genetic variation in the TAS2R38 taste receptor contributes to the oral microbiota in North and South European locations: a pilot study

BackgroundMicrobial communities are influenced by environmental factors including host genetics. We investigated the relationship between host bitter taste receptor genotype hTAS2R38 and oral microbiota, together with the influence of geographical location.MethodshTAS2R38 polymorphisms and 16S bacterial gene sequencing from oral samples were analyzed from a total of 45 healthy volunteers from different geographical locations.ResultsGenetic variation in the bitter taste receptor TAS2R38 reflected in the microbial composition of oral mucosa in Finnish and Spanish subjects. Multivariate analysis showed significant differences in the microbial composition between country and also dependent on taste genotype. Oral microbiota was shown to be more stable to the geographical location impact among AVI-homozygotes than PAV-homozygotes or heterozygotes (PAV/AVI).ConclusionGeographical location and genetic variation in the hTAS2R38 taste receptor impact oral mucosa microbial composition. These findings provide an advance in the knowledge regarding the interactions between taste receptor genes and oral microbiota. This study suggests the role of host-microbiota interactions on the food taste perception in food choices, nutrition, and eating behavior.<br /

Urolithin metabotypes can determine the modulation of gut microbiota in healthy individuals by tracking walnuts consumption over three days

Walnuts are rich in polyphenols ellagitannins, modulate gut microbiota (GM), and exert health benefits after long-term consumption. The metabolism of ellagitannins to urolithins via GM depends on urolithin metabotypes (UM-A, -B, or -0), which have been reported to predict host responsiveness to a polyphenol-rich intervention. This study aims to assess whether UMs were associated with differential GM modulation after short-term walnut consumption. In this study, 27 healthy individuals consumed 33 g of peeled raw walnuts over three days. GM profiling was determined using 16S rRNA illumina sequencing and specific real-time quantitative polymerase chain reactions (qPCRs), as well as microbial activity using short-chain fatty acids analysis in stool samples. UMs stratification of volunteers was assessed using ultra performance liquid chromatography-electro spray ionization-quadrupole time of flight-mass spectrometry (UPLC-ESI-QTOF-MS) analysis of urolithins in urine samples. The gut microbiota associated with UM-B was more sensitive to the walnut intervention. Blautia, Bifidobacterium, and members of the Coriobacteriaceae family, including Gordonibacter, increased exclusively in UM-B subjects, while some members of the Lachnospiraceae family decreased in UM-A individuals. Coprococcus and Collinsella increased in both UMs and higher acetate and propionate production resulted after walnuts intake. Our results show that walnuts consumption after only three days modulates GM in a urolithin metabotype-depending manner and increases the production of short-chain fatty acids (SCFA)

Impact of “chemical cocktails” exposure in shaping mice gut microbiota and the role of selenium supplementation combining metallomics, metabolomics, and metataxonomics

Biological systems are exposed to a complex environment in which pollutants can interact through synergistic or antagonistic mechanisms, but limited information is available on the combined effects. To this end, conventional and antibiotic-treated (Abx) mice models were fed regular rodent or selenium (Se) supplemented diets and exposed to a “chemical cocktail” (CC) including metals and pharmaceuticals. Metallomics, metabolomics, and metataxomics were combined to delve into the impact on gut microbiota, plasma selenoproteome, metabolome,and arsenic metabolization. At the molecular level, Se decreased the concentration of the antioxidant glutathione peroxidase in plasma and increased the arsenic methylation rate, possibly favoring its excretion, but not in the Abx and also plasma metabolomes of Abx, and Abx-Se were not differentiated. Moreover, numerous associations were obtained between plasma selenoproteins and gut microbes. Se-supplementation partially antagonizes the gut microbiota alteration caused by Abx, and slightly by CC, but strongly altered profiles were observed in CCAbx- Se, suggesting synergistic deleterious effects between pollutants, Abx and Se. Moreover, although CC and Abx changed gut microbiota, several common taxa were enriched in CC-Abx and control mice, indicating possible synergistic effects. Our results suggest a potential beneficial impact of supplementation, but mediated by gut microbes being reversed in their absence.Biological systems are exposed to a complex environment in which pollutants can interact through synergistic or antagonistic mechanisms, but limited information is available on the combined effects. To this end, conventional and antibiotic-treated (Abx) mice models were fed regular rodent or selenium (Se) supplemented diets and exposed to a “chemical cocktail” (CC) including metals and pharmaceuticals. Metallomics, metabolomics, and metataxomics were combined to delve into the impact on gut microbiota, plasma selenoproteome, metabolome, and arsenic metabolization. At the molecular level, Se decreased the concentration of the antioxidant glutathione peroxidase in plasma and increased the arsenic methylation rate, possibly favoring its excretion, but not in the Abx and also plasma metabolomes of Abx, and Abx-Se were not differentiated. Moreover, numerous associations were obtained between plasma selenoproteins and gut microbes. Se-supplementation partially antagonizes the gut microbiota alteration caused by Abx, and slightly by CC, but strongly altered profiles were observed in CC-Abx-Se, suggesting synergistic deleterious effects between pollutants, Abx and Se. Moreover, although CC and Abx changed gut microbiota, several common taxa were enriched in CC-Abx and control mice, indicating possible synergistic effects. Our results suggest a potential beneficial impact of supplementation, but mediated by gut microbes being reversed in their absence.This work was supported by the projects: PG2018–096608-B-C21 from the Spanish Ministry of Science and Innovation (MICIN). Generaci´on del Conocimiento. MCIN/ AEI /10.13039/501100011033/ FEDER “Una manera de hacer Europa’’, UHU-1256905 and UHU- 202009 from the FEDER Andalusian Operative Program 2014–2020 (Ministry of Economy, Knowledge, Business and Universities, Regional Government of Andalusia, Spain). The authors are grateful to FEDER (European Community) for financial support, Grant UNHU13–1E-1611. Funding for open access charge: Universidad de Huelva / CBUA. The authors would like to acknowledge the support from The Ram´on Areces Foundation (ref. CIVP19A5918)

Pregestational overweight and obesity are associated with differences in gut microbiota composition and systemic inflammation in the third trimester

The obesity epidemic is a global challenge, and the velocity of propagation is high in the population at reproductive age. Overweight and obesity during pregnancy have been associated with high birth weight and an increased risk of childhood obesity, reinforcing the risk of other non-communicable diseases. Obesity involves chronic low-grade systemic inflammation. New biomarkers for early detection of obesity risk are urgently required. The aim of this study was to identify the connection between pregestational BMI (pre-BMI) status and inflammatory biomarkers during the third trimester of pregnancy and their association with intestinal microbiota composition. Fifty-four pregnant women were classified according to pre-pregnancy BMI as normoweight, overweight, or obese. Weight gain, inflammatory biomarkers (hs_CRP, haptoglobin, and suPAR), and microbiota composition were assessed during the third trimester. A significant lower weight gain for obese mothers and a positive correlation between pre-BMI and inflammatory biomarkers were detected (Spearman's correlation). Haptoglobin levels were significantly higher in overweight and obese mothers. Higher Firmicutes levels and a higher ratio Firmicutes/Bacteroidetes were observed in the overweight and obese subjects. High hs_CRP and haptoglobin levels were also correlated with decreased microbiota diversity (Shannon index), whereas haptoglobin and hs_CRP values were correlated with several microbiota components, such as Ruminococcus gnavus and Faecalibacterium, and with specific phyla in the normoweight and overweight mothers; no significant associations with microbiota were found for suPAR. In conclusion, haptoglobin and hs_CRP reflected pregestational BMI status and related microbiota components, but haptoglobin was a better biomarker for microbiota associated with overweight. suPAR was associated with low grade inflammation dependent on pre-pregnancy BMI, but it was not related to deviated microbiota profiles

Mice brain metabolomics after the exposure to a “chemical cocktail” and selenium supplementation through the gut-brain axis

Several environmental pollutants have been shown to damage brain and affect gut microbiota. Limited evidence is available about the impact of “chemical cocktails” (CC) of xenobiotics on brain metabolome and their possible influence in the gut-brain crosstalk. To this end, BALB/c mice were exposed to heavy metals (As, Hg, Cd) and pharmaceuticals (diclofenac and flumequine) under regular rodent diet or supplemented with selenium (Se). Selenium, an antioxidant well-known for its antagonism against the neurotoxicity of several pollutants, modulated several brain metabolic impairments caused by CC (e.g., brain levels of the excitatory amino acid N-acetyl aspartic acid) by influencing mainly the metabolisms of purine, glycosylate and dicarboxylate, glutamate, glycerophospholipid, alanine and aspartate. Numerous associations were obtained between brain metabolites and gut microbes and they changed after Se-supplementation (e.g., Lactobacillus was positively associated with a brain ceramide, phosphoserine, phosphocholine, vitamin D3 derivative, fatty acids, malic acid, amino acids, and urea after the exposure, but not after Se-supplementation). Our results showed numerous evidences about the impact of CC on brain metabolome, the potential role of Se as an antagonist and their impact on the gut-brain axis. Further research is needed to understand the complex mechanism of action implied on CC-brain-microbiota interactions.This work was supported by the projects: PG2018–096608-B-C21 and PID2021-123073NB-C21 from the Spanish Ministry of Science and Innovation (MICIN). Generación del Conocimiento. MCI/AEI/ FEDER “Una manera de hacer Europa”, UHU-1256905 and UHU-202009 from the FEDER Andalusian Operative Program 2014–2020 (Ministry of Economy, Knowledge, Business and Universities, Regional Government of Andalusia, Spain). The authors are grateful to FEDER (European Community) for financial support, Grant UNHU13–1E-1611. CPM thanks MICIN for a predoctoral grant (ref. PRE2019–091650). Funding for open access charge: Universidad de Huelva / CBUA. The authors would like to acknowledge the support from The Ramón Areces Foundation (ref. CIVP19A5918)

HPV infection and bacterial microbiota in the placenta, uterine cervix and oral mucosa

We investigated the association between HPV infection and bacterial microbiota composition in the placenta, uterine cervix and mouth in thirty-nine women. HPV DNA genotyping of 24 types was conducted using Multimetrix (R). Microbiota composition was characterized by 16S rRNA gene sequencing. HPV DNA was detected in 33% of placenta, 23% cervical and 33% oral samples. HPV16 was the most frequent type in all regions. HPV infection was associated with higher microbiota richness (p = 0.032) in the mouth but did not influence microbial diversity or richness in other samples. HPV infection was associated with higher abundance of Lactobacillaceae (p = 0.0036) and Ureaplasma (LDA score > 4.0, p < 0.05) in the placenta, Haemophilus (p = 0.00058) and Peptostreptococcus (p = 0.0069) genus in the cervix and Selenomonas spp. (p = 0.0032) in the mouth compared to HPV negative samples. These data suggest altered bacterial microbiota composition in HPV positive placenta, cervix and mouth. Whether the changes in bacterial microbiota predispose or result from HPV remains to be determined in future studies

Maternal and perinatal factors associated with the human milk microbiome

Microbes are present in human milk regardless of the mother's health. The origins of the milk microbiota likely include the mother's skin, infant's mouth, and transfer from the maternal gastrointestinal (GI) tract. Prominent bacterial taxa in human milk are Staphylococcus and Streptococcus, but many other genera are also found including anaerobic Lactobacillus, Bifidobacterium, and Bacteroides. The milk microbiome is highly variable and potentially influenced by geographic location, delivery mode, time postpartum, feeding mode, social networks, environment, maternal diet, and milk composition. Mastitis alters the milk microbiome, and the intake of Lactobacilli has shown potential for mastitis treatment and prevention. Although milk and infant fecal microbiomes are different, their variations appear to be related – suggesting that milk is an important contributor of early GI colonization. Nonetheless, nothing is known regarding whether the milk microbiome influences infant health. Further research and clinical interventions are needed to determine if changes in the microbiomes of human milk and infant formula/food impact health.</p