The probiotic Lacticaseibacillus rhamnosus HN001 influences the architecture and gene expression of small intestine tissue in a piglet model.

This study investigated the effects of Lacticaseibacillus rhamnosus HN001 supplementation on the architecture and gene expression in small intestinal tissues of piglets used as an animal model for infant humans. Twenty-four 10-d-old entire male piglets (4·3 (sd 0·59) kg body weight) were fed an infant formula (IF) (control) or IF supplemented with 1·3 × 105 (low dose) or 7·9 × 106 (high dose) colony-forming units HN001 per ml of reconstituted formula (n 8 piglets/treatment). After 24 d, piglets were euthanised. Samples were collected to analyse the histology and gene expression (RNAseq and qPCR) in the jejunal and ileal tissues, blood cytokine concentrations, and blood and faecal calprotectin concentrations. HN001 consumption altered (false discovery rate < 0·05) gene expression (RNAseq) in jejunal tissues but not in ileal tissues. The number of ileal goblet cells and crypt surface area increased quadratically (P < 0·05) as dietary HN001 levels increased, but no increase was observed in the jejunal tissues. Similarly, blood plasma concentrations of IL-10 and calprotectin increased linearly (P < 0·05) as dietary HN001 levels increased. In conclusion, supplementation of IF with HN001 affected the architecture and gene expression of small intestine tissue, blood cytokine concentration and frequencies, and blood calprotectin concentrations, indicating that HN001 modulated small intestinal tissue maturation and immunity in the piglet model.

Short communication: Processed bovine colostrum milk protein concentrate increases epithelial barrier integrity of Caco-2 cell layers.

Colostrum plays an important role in initiating the development of the intestinal barrier in newborn mammals. Given its bioactivity, there is much interest in the potential use of bovine colostrum to improve human gastrointestinal health throughout the life span. There is evidence that bovine colostrum is effective at improving small intestinal barrier integrity and some indication that it may alter colonic motility. However, for colostrum to be used as a product to improve intestinal health, it needs to be bioactive after processing. The aim of this study was to determine whether industrial processing of bovine colostrum affects its ability to improve small intestinal barrier integrity or alter distal colon motility. Three colostrum sample types were compared; raw whole colostrum powder (WCP), raw skim colostrum powder (SCP), and industrially produced colostrum milk protein concentrate (CMPC). To determine whether these colostrum powders had different effects on small intestinal barrier integrity, their effects on the transepithelial electrical resistance across an in vitro intestinal epithelial layer (Caco-2 cells) were measured, both with and without a challenge from the proinflammatory cytokine tumor necrosis factor-α. These results showed that CMPC enhanced transepithelial electrical resistance across unchallenged epithelial cell layers, whereas the raw colostrum samples, WCP and SCP, did not have an effect. The colostrum samples were also compared to determine how they affect contractility in the distal colon isolated from the rat. Skim colostrum powder was the only sample to act directly on colonic tissue to modulate motility, increasing the amplitude of contractions. The results show that bovine colostrum is able to improve small intestinal barrier integrity and alter colon motility, and they implicate different components. The barrier integrity enhancement was apparent only in the industrial CMPC, which may have been due to the increase in protein concentration or the release of small peptides as a result of processing. The ability to alter colon motility was present in SCP but absent in WCP, again implying that an increase in protein concentration is responsible for the effect. However, this effect was not apparent for the industrially processed CMPC, suggesting denaturation or degradation of the active component. The beneficial effect of colostrum on small intestinal barrier integrity was present after processing, confirming that it is feasible to industrially produce an active product for gut health.

Impacts of Formula Supplemented with Milk Fat Globule Membrane on the Neurolipidome of Brain Regions of Piglets.

The milk fat globule membrane (MFGM) appears to play an important role in infant neurocognitive development; however, its mechanism(s) of action remains unclear. This study aimed to investigate the role of a dietary MFGM supplement on the lipid profiles of different neonatal brain regions. Ten-day-old male piglets (4−5 kg) were fed unsupplemented infant formula (control, n = 7) or an infant formula supplemented with low (4%) or high (8%) levels of MFGM (n = 8 each) daily for 21 days. Piglets were then euthanized, and brain tissues were sectioned. Untargeted liquid chromatography-mass spectrometry lipidomics was performed on the cerebellum, hippocampus, prefrontal cortex, and the rest of the brain. The analyses identified 271 and 171 lipids using positive and negative ionization modes, respectively, spanning 16 different lipid classes. MFGM consumption did not significantly alter the lipidome in most brain regions, regardless of dose, compared to the control infant formula. However, 16 triacylglyceride species were increased in the hippocampus (t-test, p-value < 0.05) of the high-supplemented piglets. Most lipids (262 (96.7%) and 160 (93.6%), respectively) differed significantly between different brain regions (ANOVA, false discovery rate corrected p-value < 0.05) independent of diet. Thus, this study highlighted that dietary MFGM altered lipid abundance in the hippocampus and detected large differences in lipid profiles between neonatal piglet brain regions.

Lacticaseibacillus rhamnosus HN001 alters the microbiota composition in the cecum but not the feces in a piglet model.

The probiotic Lacticaseibacillus rhamnosus strain HN001 has been shown to have several beneficial health effects for both pediatric and maternal groups, including reduced risk of eczema in infants and gestational diabetes and postnatal depression in mothers. While L. rhamnosus HN001 appears to modify immune and gut barrier biomarkers, its mode of action remains to be fully elucidated. To gain insights into the role of HN001 on the infant microbiome, the impacts of L. rhamnosus HN001 supplementation was studied in 10-day old male piglets that were fed either infant formula, or infant formula with L. rhamnosus HN001 at a low (1.3 × 105 CFU/ml) or high dose (7.9 × 106 CFU/ml) daily for 24 days. The cecal and fecal microbial communities were assessed by shotgun metagenome sequencing and host gene expression in the cecum and colon tissue was assessed by RNA-seq. Piglet fecal samples showed only modest differences between controls and those receiving dietary L. rhamnosus HN001. However, striking differences between the three groups were observed for cecal samples. While total lactobacilli were significantly increased only in the high dose L. rhamnosus HN001 group, both high and low dose groups showed an up to twofold reduction across the Firmicutes phylum and up to fourfold increase in Prevotella compared to controls. Methanobrevibacter was also decreased in HN001 fed piglets. Microbial genes involved in carbohydrate and vitamin metabolism were among those that differed in relative abundance between those with and without L. rhamnosus HN001. Changes in the cecal microbiome were accompanied by increased expression of tight junction pathway genes and decreased autophagy pathway genes in the cecal tissue of piglets fed the higher dose of L. rhamnosus HN001. Our findings showed supplementation with L. rhamnosus HN001 caused substantial changes in the cecal microbiome with likely consequences for key microbial metabolic pathways. Host gene expression changes in the cecum support previous research showing L. rhamnosus HN001 beneficially impacts intestinal barrier function. We show that fecal samples may not adequately reflect microbiome composition higher in the gastrointestinal tract, with the implication that effects of probiotic consumption may be missed by examining only the fecal microbiome.

Goat milk increases gastric emptying and alters caecal short chain fatty acid profile compared with cow milk in healthy rats.

Goat and cow milk share similar protein and lipid content, yet goat milk forms softer curds during stomach digestion. This has been assumed to hasten gastric emptying (GE) on consumption of goat milk compared with cow milk, although there is no direct evidence for this. We hypothesised that goat milk would increase GE and gastrointestinal transit compared with cow milk and alter short-chain fatty acid (SCFA) profiles. Ten week old rats were provided with a non-dairy diet and goat milk, cow milk, or water, ad libitum for two weeks. On day 14, X-ray imaging tracked the transit of metallic beads in vivo over 15 h. SCFA analysis of the caecal content was carried out post-mortem. Goat milk consumption increased GE compared with cow milk and controls, whereas colonic transit was slowed for both milk consuming groups. Goat milk altered the SCFA profile compared to controls. In particular, acetic and propionic acids in the caecum were present at a higher concentration in goat milk-fed rats. There was no difference between the SCFA profiles of cow milk and control animals. The more rapid gastric emptying conferred by goat milk supplementation provides evidence for improved digestibility. The slower colonic transit by both milks was associated with similar changes in motility associated with SCFA that suggest altered carbohydrate fermentation and lower levels of amino acid fermentation in the caecum.