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Pausan, M.-R.

Publications and source records attributed to Pausan, M.-R..

3 recordsLinked to original sources

First-Year Dynamics of the Anaerobic Microbiome and Archaeome in Infants Oral and Gastrointestinal Systems

Recent research provides new insights into the early establishment of the infant gut microbiome, emphasizing the influence of breastfeeding on the development of gastrointestinal (GIT) microbiomes. In our study, we longitudinally examined the taxonomic and functional dynamics of the oral and GIT microbiomes of healthy infants (n=30) in their first year, focusing on the often over-looked aspects, the development of archaeal and anaerobic microbiomes. Breastfed (BF) infants exhibit a more defined transitional phase in their oral microbiome compared to non-breastfed (NBF) infants, marked by a decrease in Streptococcus and the emergence of anaerobic genera such as Granulicatella. This phase, characterized by increased alpha diversity and significant changes in beta diversity, occurs earlier in NBF infants (months 1-3) than in BF infants (months 4-6), suggesting that breastfeeding supports later, more defined microbiome maturation. We demonstrated the presence of archaea in the infant oral cavity and GIT microbiome from early infancy, with Methanobrevibacter being the predominant genus. Still, transient patterns show that no stable archaeome is formed. The GIT microbiome exhibited gradual development, with BF infants showing increased diversity and complexity between months 3 and 8, marked by anaerobic microbial networks. NBF infants displayed complex microbial co-occurrence patterns from the start. Those strong differences between BF and NBF infants GIT microbiomes are less pronounced on functional levels than on taxonomic level. Overall, the infant microbiome differentiates and stabilizes over the first year, with breastfeeding playing a crucial role in shaping anaerobic microbial networks and overall microbiome maturation.

microbiology↗

The Dynamics of the Female Microbiome: Unveiling Abrupt Changes of Microbial Domains across Body Sites from Preconception to Perinatal Phase

The microbial ecosystem of women undergoes enormous changes during pregnancy and the perinatal period. Little is known about the extent of changes in the maternal microbiome beyond the vaginal cavity and its recovery after birth. In this study, we followed pregnant women (mpre, n = 30) into the postpartum period (1 month postpartum, mpost, n = 30). We profiled their oral, urinary, and vaginal microbiome, archaeome, mycobiome and urinary metabolome and compared them with nonpregnant women (np, n = 29). Overall, pregnancy status (np, mpre, mpost) had a smaller effect on the microbiomes than body site, but massive transitions were observed for the oral and urogenital (vaginal and urinary) microbiomes. While the oral microbiome fluctuates during pregnancy but stabilizes rapidly within the first month postpartum, the urogenital microbiome is characterized by a major remodeling caused by a massive loss of Lactobacillus and thus a shift from vaginal community state type (CST) I (40% of women) to CST IV (85% of women). The urinary metabolome rapidly reached an np-like composition after delivery, apart from lactose and oxaloacetic acid, which were elevated during active lactation. Fungal and archaeal profiles were indicative of pregnancy status. Methanobacterium signatures were found exclusively in np women, and Methanobrevibacter showed opposite behavior in oral cavity (increased) and vagina (decreased) during pregnancy. Our findings suggest that the massive remodeling of the maternal microbiome and metabolome needs more attention and that potential interventions could be envisioned to optimize recovery and avoid long-term effects on maternal health and subsequent pregnancies.

microbiology↗

Human Milk Oligosaccharides modulate the risk for preterm birth in a microbiome dependent and independent manner

BackgroundPreterm birth is one of the leading causes of neonatal mortality. The causes for spontaneous preterm birth (PTB) are multifactorial and remain often unknown. In this study, we tested the hypothesis that human milk oligosaccharides (HMOs) in blood and urine modulate the maternal urinary and vaginal microbiome and influence the risk for PTB. We analyzed the vaginal and urinary microbiome of a cross-sectional cohort of women with and without preterm labor and correlated our findings with measurements of metabolites and HMOs in urine and blood.\n\nResultsWe identified several microbial signatures associated with short cervix, PTB and/or preterm contractions such as Lactobacillus jensenii, L. gasseri, Ureaplasma sp. and Gardnerella sp.. Additionally, we observed associations between sialylated HMOs, in particular 3-sialyllactose, with PTB, short cervix and increased inflammation and confirmed an influence of HMOs on the microbiome profile.\n\nConclusionsIdentifying serum and urinary HMOs and several key microorganisms associated with PTB, our findings point at two distinct processes modulating the risk for PTB. One process seems to be driven by sterile inflammation, characterized by increased concentrations of sialylated HMOs in serum. Another process might be microbiome-mediated, potentially driven by secretor-active HMOs in urine. Our results support current efforts to improve diagnostics and therapeutic strategies.

microbiology↗