Biology subjects

Pruss, K. M.

Publications and source records attributed to Pruss, K. M..

5 recordsLinked to original sources

bioRxiv2026

Small intestinal microbiota of undernourished women perturbs placental development in mice

Children of undernourished women have impaired pre- and postnatal growth. Undernourished women and children have a high incidence of environmental enteric dysfunction (EED), an enteropathy characterized by gut barrier dysfunction and systemic inflammation. Here, we employ gnotobiotic mice to compare the effects of bacterial consortia cultured from the duodenal microbiota of Bangladeshi women with EED and their healthy counterparts. Female mice harboring the EED-derived consortium exhibited fetal and placental growth restriction. Transcriptomic and proteomic analyses disclosed pronounced effects of the EED-derived consortium on the decidual component of the maternal-fetal interface involving tissue-resident uterine natural killer (uNK) cells and disruption of TGF-{beta} signaling between uNK and decidual stromal cells. Co-housing mice with EED and healthy consortia ameliorated these effects, disclosing bacterial targets to improve prenatal development.

systems biology↗

bioRxiv2024

Effects of intergenerational transmission of small intestinal bacteria cultured from stunted Bangladeshi children with enteropathy

Environmental enteric dysfunction (EED), a small intestinal disorder found at a high prevalence in stunted children, is associated with gut mucosal barrier disruption and decreased absorptive capacity1-4. To test the hypothesis that intergenerational transmission of a perturbed small intestinal microbiota contributes to undernutrition by inducing EED5, we characterized two consortia of bacterial strains cultured from duodenal aspirates from stunted Bangladeshi children with EED - one of which induced local and systemic inflammation in female gnotobiotic mice. Offspring of dams colonized with the inflammatory consortium exhibited impaired prenatal and postnatal growth, as well as immunologic changes phenocopying features of EED in children. Dam-to-pup transmission of the inflammatory consortium produced, in recently weaned offspring, alterations in inter-cellular signaling pathways related to intestinal epithelial cell renewal, barrier integrity and immune function. Cohousing of mice harboring the inflammatory or non-inflammatory consortia and subsequent screening of candidate disease-promoting bacterial isolates identified Campylobacter concisus, an organism typically found in the oral microbiota, as a contributor to enteropathy. The C. concisus strain induced, in a host nitric oxide synthase (NOS)-dependent manner, pro-inflammatory cytokine signaling. Moreover, host-derived nutrients generated by NOS augmented C. concisus growth. This preclinical model should facilitate identification of small intestinal microbiota-targeted therapeutics for (intergenerational) undernutrition.

systems biology↗

bioRxiv2023

Prevotella copri-linked effects of a therapeutic food for malnutrition

Preclinical and clinical studies are providing evidence that the healthy growth of infants and children reflects, in part, healthy development of their gut microbiomes1-5. This process of microbial community assembly and functional maturation is perturbed in children with acute malnutrition. Gnotobiotic animals, colonized with microbial communities from children with severe and moderate acute malnutrition, have been used to develop microbiome-directed complementary food (MDCF) formulations for repairing the microbiomes of these children during the weaning period5. Bangladeshi children with moderate acute malnutrition (MAM) participating in a previously reported 3-month-long randomized controlled clinical study of one such formulation, MDCF-2, exhibited significantly improved weight gain compared to a commonly used nutritional intervention despite the lower caloric density of the MDCF6. Characterizing the metagenome assembled genomes (MAGs) of bacterial strains present in the microbiomes of study participants revealed a significant correlation between accelerated ponderal growth and the expression by two Prevotella copri MAGs of metabolic pathways involved in processing of MDCF-2 glycans1. To provide a direct test of these relationships, we have now performed reverse translation experiments using a gnotobiotic mouse model of mother-to-offspring microbiome transmission. Mice were colonized with defined consortia of age- and ponderal growth-associated gut bacterial strains cultured from Bangladeshi infants/children in the study population, with or without P. copri isolates resembling the MAGs. By combining analyses of microbial community assembly, gene expression and processing of glycan constituents of MDCF-2 with single nucleus RNA-Seq and mass spectrometric analyses of the intestine, we establish a principal role for P. copri in mediating metabolism of MDCF-2 glycans, characterize its interactions with other consortium members including Bifidobacterium longum subsp. infantis, and demonstrate the effects of P. copri-containing consortia in mediating weight gain and modulating the activities of metabolic pathways involved in lipid, amino acid, carbohydrate plus other facets of energy metabolism within epithelial cells positioned at different locations in intestinal crypts and villi. Together, the results provide insights into structure/function relationships between MDCF-2 and members of the gut communities of malnourished children; they also have implications for developing future prebiotic, probiotic and/or synbiotic therapeutics for microbiome restoration in children with already manifest malnutrition, or who are at risk for this pervasive health challenge.

microbiology↗

bioRxiv2020

Mucin-derived O-glycans supplemented to diet mitigate diverse microbiota perturbations

Microbiota-accessible carbohydrates (MACs) are powerful modulators of microbiota composition and function. These substrates are often derived from diet, such as complex polysaccharides from plants or human milk oligosaccharides (HMOs) during breastfeeding. Host-derived mucus glycans on gut-secreted mucin proteins may serve as a continuous endogenous source of MACs for resident microbes; here we investigate the potential role of purified, orally-administered mucus glycans in maintaining a healthy microbial community. In this study, we liberated and purified O-linked glycans from porcine gastric mucin and assessed their efficacy in shaping the recovery of a perturbed microbiota in a mouse model. We found that porcine mucin glycans (PMGs) and HMOs enrich for taxonomically similar resident microbes. We demonstrate that PMGs aid recovery of the microbiota after antibiotic treatment, suppress C. difficile abundance, delay the onset of diet-induced obesity, and increase relative abundance of resident Akkermansia muciniphila. In silico analysis revealed that genes associated with mucus utilization are abundant and diverse in prevalent gut commensals and rare in enteric pathogens, consistent with these glycan-degrading capabilities being selected for during host development and throughout evolution of the host-microbe relationship. Importantly, we identify mucus glycans as a novel class of prebiotic compounds that can be used to mitigate perturbations to the microbiota and provide benefits to host physiology.

microbiology↗

bioRxiv2019

Recovery of the gut microbiota after antibiotics depends on host diet and environmental reservoirs

That antibiotics alter microbiota composition and increase infection susceptibility is well known, but their generalizable effects on the gut commensal community and dependence on environmental variables remain open questions. Here, we systematically compared antibiotic responses in gnotobiotic and conventional mice across antibiotics, microbiotas, diets, and housing status. We identify remarkable resilience, whereby a humanized microbiota recovers before drug administration ends, with transient dominance of resistant Bacteroides and taxa-asymmetric reduction in diversity. In other cases, in vitro sensitivities were not predictive of in vivo responses, underscoring the significance of host and community contexts. A fiber-deficient diet exacerbated collapse of the microbiota and delayed recovery, despite the presence of a similar core community across diets at the point of maximal disturbance. Resilience to a second ciprofloxacin treatment was observed via response reprogramming, in which species replacement after ciprofloxacin treatment established resilience to a second treatment, and also through cross housing transmission. Single-housing drastically disrupted recovery, highlighting the importance of environmental microbial reservoirs and suggesting sanitation may exacerbate the duration of antibiotic-mediated disruption. Our findings highlight the ability of the commensal microbiota to deterministically adapt to large perturbations, and the translational potential for modulating diet, sanitation, and microbiota composition during antibiotics.

microbiology↗