Title : The research on Lactobacillus reuteri ZY15 in improving intestinal inflammation in offspring within a mother-piglet model
Abstract:
Weaning stress triggers inflammatory diarrhea in piglets, presenting a substantial challenge to the growth performance and mortality rate of piglets. Consequently, the mother-piglet relationship serves as an ideal model for mother-offspring research. Based on the differences in gut microbiota between weaned healthy and diarrheal piglets, functional bacterial communities, such as Bifidobacterium, Lactobacillus, Limosilactobacillus, Prevotella, Mitsuokella, Megasphaera, Acidaminococcus, were cultured using the external simulation culture technique. Subsequently, Lactobacillus reuteri ZY15 was isolated from the in vitro culture system by means of culture omics technology. In vitro evaluation indicated that L. reuteri ZY15 exhibited excellent properties in terms of acid resistance, bile salt tolerance, adhesion to Caco-2 and IPEC-J2 cells, and inhibition of the growth of E. coli K88, Staphylococcus aureus, and Salmonella. Twenty healthy sows in late gestation (14 days prior to farrowing) with similar body weights were randomly assigned to two groups: a control group (CS) fed a basal diet and a treatment group (LS) fed a basal diet supplemented with L. reuteri ZY15. After farrowing, the piglets from both groups were further divided into two subgroups: one subgroup was gavaged with L. reuteri ZY15 daily until weaning at 21 days (LP group), and the other subgroup received physiological saline (CP group). Sows fed L. reuteri ZY15 exhibited a significant increase of over 10% in the birth weight and weanling weight of piglets. Moreover, when sows were fed with L. reuteri ZY15 and Piglets were gavaged with L. reuteri ZY15, there were significant improvements in intestinal inflammation and cell apoptosis of weaned piglets. Combined with transcriptome analysis, it was demonstrated that L. reuteri ZY15 alleviated intestinal inflammation via the Akt/mTOR/HIF-1α/RORγt/IL-17 pathway in an ETEC K88-challenge miouse model. Non-targeted metabolomics revealed that sows fed with L. reuteri ZY15 significantly altered the lysophospholipids metabolism in cord blood and breast milk. These may be the key maternal metabolites that alleviated intestinal inflammation. Sows fed L. reuteri ZY15 restructured the gut microbial community in piglets. Specifically, this led to an increase in the relative abundances of Lactobacillus and Treponema, while reducing the relative abundances of Phascolarctobacterium. In addition, it significantly modified the transfer of passive immunity (immunoglobulin A, M and G) from mother to offspring. This, in turn, reshaped the gut bacterial community of piglets and thus alleviated weanling stress in these piglets. Taken together, our findings uncovered the protective mechanism of L. reuteri ZY15 in piglets and the key maternal metabolites. The corresponding results provided a theoretical foundation for the mother-offspring integration research and its nutritional regulation strategies.
