Porcine Milk Exosome MiRNAs Attenuate LPS-Induced Apoptosis through Inhibiting TLR4/NF-κB and p53 Pathways in Intestinal Epithelial Cells

Abstract

Lipopolysaccharide (LPS) is a bacterial endotoxin that induces intestine inflammation. Milk exosomes improve the intestine and immune system development of newborns. This study aims to establish the protective mechanisms of porcine milk exosomes on the attenuation of LPS-induced intestinal inflammation and apoptosis. In vivo, exosomes prevented LPSinduced intestine damage and inhibited (p < 0.05) LPS-induced inflammation. In vitro, exosomes inhibited (p < 0.05) LPSinduced intestinal epithelial cells apoptosis (23% ± 0.4% to 12% ± 0.2%). Porcine milk exosomes also decreased (p < 0.05) the LPS-induced TLR4/NF-κB signaling pathway activation. Furthermore, exosome miR-4334 and miR-219 reduced (p < 0.05) LPS-induced inflammation through the NF-κB pathway and miR-338 inhibited (p < 0.05) the LPS-induced apoptosis via the p53 pathway. Cotransfection with these three miRNAs more effectively prevented (p < 0.05) LPS-induced cell apoptosis than these miRNAs individual transfection. The apoptosis percentage in the group cotransfected with the three miRNAs (14% ± 0.4%) was lower (p < 0.05) than that in the NC miRNA group (28% ± 0.5%), and also lower than that in each individual miRNA group. In conclusion, porcine milk exosomes protect the intestine epithelial cells against LPS-induced injury by inhibiting cell inflammation and protecting against apoptosis through the action of exosome miRNAs. The presented results suggest that the physiological amounts of miRNAs-enriched exosomes addition to infant formula could be used as a novel preventative measure for necrotizing enterocolitis.

The Oviductal Extracellular Vesicles’ RNA Cargo Regulates the Bovine Embryonic Transcriptome

“…It has been proposed that exosomal miRNAs such as let-7, miR-21, and miR-29a, identified in oEVs, can act as an unconventional mode to activate TLR7 in mice and cause neurodegeneration and tumor growth and metastasis [59,60]. In the same line, milk exosomal miRNAs have been shown to decrease LPS-induced TLR4/NF-κB signaling pathway activation, reducing LPS-induced inflammation through the NF-κB pathway and inhibiting LPS-induced apoptosis via the p53 pathway [61]. Altogether, these data suggest that miRNAs present in oEVs could regulate components of TLR pathways in the embryo, modulating the maternal immune system at the maternal-fetal interface.…”

Oral Administration of Bovine Milk‐Derived Extracellular Vesicles Alters the Gut Microbiota and Enhances Intestinal Immunity in Mice

“…And numerous studies further showed that mEVs and their cargos played a critical role on attenuating LPS‐induced apoptosis, preventing the development of experimental necrotizing enterocolitis and promoting microbial growth. [ 15–17 ] In addition, mEVs could resist the harsh environment (low pH, high temperature, enzymatic treatment) of the gastrointestinal tract and reach the intestinal lumen. [ 18–20 ] Thus, mEVs might involve in several immunomodulatory mechanisms, intestinal tract development, and reshaping of the gut microbiota.…”

Milk Exosomes Prevent Intestinal Inflammation in a Genetic Mouse Model of Ulcerative Colitis: A Pilot Experiment

“…Whether nonabsorbed exosomes also act from the luminal side is not elucidated. Recent evidence indicates that milk exosomes play a critical role for intestinal maturation and function in humans and rodent models [22][23][24][25][26][27][28]. It has been demonstrated in murine models that human, bovine, and porcine milk exosomes support intestinal cell growth [22][23][24], attenuate LPS-induced apoptosis [25], prevent intestinal endothelial cell damage [26,27], enhance goblet cell numbers and mucin production [28], modify bacterial growth, and promote intestinal microbiota [29,30].…”

“…Recent evidence indicates that milk exosomes play a critical role for intestinal maturation and function in humans and rodent models [22][23][24][25][26][27][28]. It has been demonstrated in murine models that human, bovine, and porcine milk exosomes support intestinal cell growth [22][23][24], attenuate LPS-induced apoptosis [25], prevent intestinal endothelial cell damage [26,27], enhance goblet cell numbers and mucin production [28], modify bacterial growth, and promote intestinal microbiota [29,30]. Accumulating evidence indicates that milk exosomes exert barrier-protective and anti-inflammatory effects in rodent models of necrotizing enterocolitis (NEC) and NEC in human infants [25][26][27][28][29][30][31][32].…”