Project description:The interplay between the intestinal microbiota and host is critical to intestinal ontogeny and homeostasis. MicroRNAs (miRNAs) may be an underlying link. Intestinal miRNAs are microbiota-dependent and when shed in the lumen, affect resident microorganisms. Yet, longitudinal relationships between intestinal tissue miRNAs, luminal miRNAs, and luminal microorganisms have not been elucidated, especially in early life. Here, we investigated the postnatal cecal miRNA and microbiota populations, their relationship, and their impact on intestinal maturation in specific and opportunistic pathogen free mice; we also assessed if they can be modified by an intervention with allochthonous probiotic lactobacilli. We report that cecal and cecal content miRNA and microbiota signatures are temporally regulated, correlated, and modifiable by probiotics with implications for intestinal maturation. These findings help with understanding causal relationships within the gut ecosystem and provide a basis for preventing and managing their alterations in diseases throughout life.
Project description:Neonatal mice were susceptible to cryptosporidium infection at 1- and 2-weeks of age, but were resistant to infection at 3- and 6-weeks of age. Diet and microbial changes are known to occur during the weaning transition in mice and we hypothesized that these changes in the intestinal luminal environment might influence resistance and susceptibility to cryptosporidium infection. As one part of testing this hypothesis, cecal microbiota composition was determined by 16S ribosomal RNA sequencing of DNA isolated from the cecal contents of mice at 1 week, 2 weeks, 3 weeks, and 6 weeks of age.
