Profiles of Intestinal Flora in Breastfed Obese Children and Selecting Functional Strains Against Obesity.

SCOPE: Breast milk has the potential to prevent childhood obesity by providing probiotics, but there are still instances of obesity in breastfed children. METHODS AND RESULTS: This study investigates the difference in intestinal flora structure between breastfed children with obesity (OB-BF) and normal-weight breastfed children (N-BF). Building upon this foundation, it employs both cell and mouse models to identify an antiobesity strain within the fecal matter of N-BF children and explore its underlying mechanisms. The results reveal a reduction in lactobacillus levels within the intestinal flora of OB-BF children compared to N-BF children. Consequently, Lactobacillus plantarum H-72 (H-72) is identified as a promising candidate due to its capacity to stimulate glucagon-like peptide-1 (GLP-1) secretion in enteroendocrine cells (ECCs). In vivo, H-72 effectively increases serum GLP-1 concentration, reduces food intake, regulates the expression of genes related to energy metabolism (SCD-1, FAS, UCP-1, and UCP-3), and regulates gut microbiota structure in mice. Moreover, the lipoteichoic acid of H-72 activates toll-like receptor 4 to enhanced GLP-1 secretion in STC-1 cells. CONCLUSIONS: L. plantarum H-72 is screened out for its potential antiobesity effect, which presents a potential and promising avenue for future interventions aimed at preventing pediatric obesity in breastfed children.

Lactobacillus rhamnosus MN-431 Metabolic Tryptophan Alleviates Complementary Food-Induced Diarrhea through PXR-NF-κB Pathway and AHR-Th17 Cell Response Pathways.

SCOPE: Lactobacillus rhamnosus MN-431 tryptophan broth culture (MN-431 TBC) can prevent complementary food-induced diarrhea (CFID). However, it is not clear whether this effect is related to indole derivatives. METHODS AND RESULTS: In this study, the anti-CFID effects of different components in MN-431 TBC including MN-431 cells, unfermented tryptophan broth, and supernatant of MN-431 TBC (MN-431 TBS) are investigated. Only MN-431 TBS can significantly prevent CFID, indicating that indole derivatives produced by MN-431 can exert antidiarrheal effects. Intestinal morphological analysis reveals that MN-431 TBS can increase the number of goblet cells, height of ileal villi, and length of rectal glands while also increasing the expression of ZO-1 in colon. Furthermore, HPLC analysis reveals the indole derivatives in MN-431 TBS are IAld and skatole. Cell experiments demonstrate that MN-431 TBS promotes the transcription of aryl hydrocarbon receptor (AHR) and pregnane X receptor (PXR), comparable to the synergistic effect of IAld and skatole. MN-431 TBS can activate AHR and reduces the concentrations of Th17 cell-inflammatory factors IL-17A and IL-21 in intestine and IL-17F, IL-21, and IL-22 in serum. MN-431 TBS can also activate PXR and reduces the concentrations of TNF-α and IL-6 in intestine and serum. CONCLUSION: MN-431 TBS, containing IAld and skatole, can exert anti-CFID effects through the AHR-Th17 and PXR-NF-κB pathways.

Lactobacillus derived from breast milk facilitates intestinal development in IUGR rats.

AIM: The intestinal microbiota contributes to infant's intestine homeostasis. This study aimed to analyse how probiotics derived from breast milk promote infant intestinal development in rat pups. METHODS AND RESULTS: The effect of potential probiotics derived from breast milk on development of intrauterine growth retardation (IUGR) newborn rats' intestine was investigated. Limosilactobacillus oris ML-329 and Lacticaseibacillus paracasei ML-446 exhibited good hydrophobicity percentages (p < 0.05). ML-446 showed a significant effect on intestinal length and weight (p < 0.05). Meanwhile, the villus height of the IUGR newborn rats fed with ML-329 was significantly higher compared with those fed with Lacticaseibacillus rhamnosus GG (p < 0.05). Moreover, ML-329 and ML-446 both significantly stimulated the proliferation and differentiation of intestinal epithelial cells by increasing the number of ki67-positive cells, goblet cells, and lysozyme-positive Paneth cells (p < 0.05) through Wnt and Notch pathway. CONCLUSIONS: The proliferation and differentiation stimulating effects of ML-329 and ML-446 on IECs in the jejunum, ileum, and colon were mediated by activating the Wnt pathway with increased expression of wnt, lrp5, and ß-catenin genes and accumulation of ß-catenin, and by downregulating the Notch signalling pathway with decreased expression of the activated notch protein. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus could facilitate IUGR rat pups' intestinal development and enhance the proliferation of Paneth cells and goblet cells. These findings provide further insights into promotion of the intestinal development by breast milk-derived beneficial microbes in early life of the IUGR newborn rats.

Effect of Lactobacillus rhamnosus MN-431 Producing Indole Derivatives on Complementary Feeding-Induced Diarrhea Rat Pups Through the Enhancement of the Intestinal Barrier Function.

SCOPE: Many infants suffer from complementary feeding-induced diarrhea (CFID). Studies have shown that intestinal microbes can enhance the intestinal barrier and prevent diarrhea by producing indole derivatives that promote pregnane X receptor (PXR) expression. METHODS AND RESULTS: In this study, the indole test and determination of the PXR concentration are performed on tryptophan broth cultures of 320-suspected Lactobacillus and Enterococcus strains. Four strains that produce indole derivatives that promote the expression of PXR are screened as potential functional probiotics. Both Lactobacillus rhamnosus MN-431 (L. rhamnosus MN-431) and Lactobacillus oris FN-448 (L. oris FN-448) can colonize the intestine of rat pups, and L. rhamnosus MN-431 can significantly decrease the incidence of diarrhea and intestinal permeability in rat pups. Using real-time qPCR and the analysis of the intestinal morphology using immunohistochemistry, it is observed that the metabolized tryptophan from L. rhamnosus MN-431 can reduce small intestinal mucosal damage by stimulating PXR/NF-κB signaling and activating PXR and aryl hydrocarbon receptor. The intestinal barrier is also enhanced by promoting the expression of tight junction proteins such as Occludin and zonula occludens-1 in baby rats. CONCLUSION: The results demonstrate that L. rhamnosus MN-431 can metabolize tryptophan to prevent infantile CFID by promoting the expression of PXR.

Delivery Mode Affects Intestinal Microbial Composition and the Development of Intestinal Epithelial Cells.

BACKGROUND: The infant's intestine contains diverse microbiota, which play an important role in an infant's health. OBJECTIVE: This study aimed to analyze the different intestinal microbiota and their function in two delivery modes [vaginal delivery and cesarean section (C-section)] and to investigate the proprieties of bacteria associated with vaginal delivery on the development of intestinal epithelial cells in rat pups. MATERIALS AND METHODS: We evaluated the intestinal microbial diversity of the stool samples of 51 infants of subjects who underwent vaginal delivery and C-section by sequencing the V4 regions of the 16S rRNA gene and predicted the function of the microbiotas. The infant stool microbiota in the vaginal delivery group was associated with the digestive system and cell growth and death, whereas that of the C-section group was associated with membrane transport. Then, we isolated the strains based on function prediction. RESULTS: A total of 95 strains were isolated in the vaginal delivery group. Bifidobacterium bifidum FL-228.1 (FL-228.1) was screened and selected owing to its good surface hydrophobicity, bacterial survivability in the simulated gastrointestinal condition and adhesion ability to the IEC-6 cell line as well as owing to the development of intestinal epithelial cells. Furthermore, in vivo experiments revealed that FL-228.1 exhibited favorable effects on the development of intestinal epithelial cells in rat pups. CONCLUSION: The results of this study indicate an apparent difference in the bacterial composition of the stool samples collected from infants of the two delivery modes. By analyzing and screening the bacteria in infant stool samples, we found that one strain, i.e., B bifidum FL-228.1, exhibited favorable effects on the development of intestinal epithelial cells.

Ligilactobacillus Salivarius LCK11 Prevents Obesity by Promoting PYY Secretion to Inhibit Appetite and Regulating Gut Microbiota in C57BL/6J Mice.

SCOPE: Obesity is a common disease worldwide and there is an urgent need for strategies to preventing obesity. METHODS AND RESULTS: The anti-obesity effect and mechanism of Ligilactobacillus salivarius LCK11 (LCK11) is studied using a C57BL/6J male mouse model in which obesity is induced by a high-fat diet (HFD). Results show that LCK11 can prevent HFD-induced obesity, reflected as inhibited body weight gain, abdominal and liver fat accumulation and dyslipidemia. Analysis of its mechanism shows that on the one hand, LCK11 can inhibit food intake through significantly improving the transcriptional and translational levels of peptide YY (PYY) in the rectum, in addition to the eventual serum PYY level; this is attributed to the activation of the toll-like receptor 2/nuclear factor-κB signaling pathway in enteroendocrine L cells by the peptidoglycan of LCK11. On the other hand, LCK11 supplementation effectively reduces the Firmicutes/Bacteroidetes ratio and shifts the overall structure of the HFD-disrupted gut microbiota toward that of mice fed on a low-fat diet; this also contributes to preventing obesity. CONCLUSION: LCK11 shows the potential to be used as a novel probiotic for preventing obesity by both promoting PYY secretion to inhibit food intake and regulating gut microbiota.

Lactiplantibacillus plantarum H-87 prevents high-fat diet-induced obesity by regulating bile acid metabolism in C57BL/6J mice.

Bile salt hydrolase (BSH)-producing bacteria are negatively related to the body weight gain and energy storage of the host. We aimed to obtain a novel BSH-producing strain with excellent anti-obesity effect and explained its mechanism. Here, we selected a strain named Lactiplantibacillus plantarum H-87 (H-87) with excellent ability to hydrolyze glycochenodeoxycholic acid (GCDCA) and tauroursodeoxycholic acid (TUDCA) in vitro from 12 lactobacilli, and evaluated its anti-obesity effect in high-fat diet (HFD)-fed C57BL/6J mice. The results suggested that H-87 could inhibit HFD-induced body weight gain, fat accumulation, liver lipogenesis and injury, insulin resistance and dyslipidemia. In addition, H-87 could colonize in the ileum and hydrolyze GCDCA and TUDCA, reflected as changes in the concentrations of GCDCA, TUDCA, CDCA and UDCA in the ileum or liver. Furthermore, the study identified that H-87 reduced TUDCA and GCDCA levels in the ileum, which decreased the GLP-1 secretion by L cells to alleviate insulin resistance in HFD-fed mice. Furthermore, H-87 increased the CDCA level in the ileum and liver to activate FXR signaling pathways to inhibit liver lipogenesis in HFD-fed mice. In addition, the decrease of intestinal conjugated bile acids (TUDCA and GCDCA) also increased fecal lipid content and decreased intestinal lipid digestibility. In conclusion, H-87 could inhibit liver fat deposition, insulin resistance and lipid digestion by changing bile acid enterohepatic circulation, and eventually alleviate HFD-induced obesity.

Breast milk contains probiotics with anti-infantile diarrhoea effects that may protect infants as they change to solid foods.

Infants often experience complementary food-induced diarrhoea (CFID), which occurs when infants switch from breast milk to solid foods. The relative abundances of Prevotella and Rothia were higher in stools of infants with CFID, while the relative abundances of Enterococcus and Escherichia were higher in healthy infants. The abundance of Lactobacillus spp. normally found in breast milk fed to infants with CFID was significantly reduced, and Enterococcus spp. were less abundant when diarrhoea occurred. Furthermore, Lactobacillus and Enterococcus were present as shared bacteria in both mother and infant, and they were considered potential anti-CFID probiotics as their relative abundances in breast milk were negatively correlated to infant CFID. Kyoto encyclopedia of genes and genomes (KEGG) functional analysis showed that the function of amino acid metabolism differed between infants with CFID and healthy infants. Therefore, CFID might be related to the decomposition of proteins in food supplements. The screening revealed seven hydrolytic casein and five hydrolytic casein and rice protein isolates from 320 suspected Lactobacillus and Enterococcus isolates. The animal experiments demonstrated that a mixture of five isolates effectively hydrolysed the casein and rice protein and prevented diarrhoea in young rats. Thus, the occurrence of CFID was found to be closely related to the intestinal and breast milk microbiota, and bacteria that could assist in the digestion of cereal proteins were involved in CFID.

Enhancing spray drying tolerance of Lactobacillus bulgaricus by intracellular trehalose delivery via electroporation.

Spray-drying is an efficient drying technique for preparing probiotic powders, but the high temperatures employed during the process results in low survival rates of lactic acid bacteria. This study aimed to enhance spray-drying tolerance of lactic acid bacteria by intracellular delivery of trehalose via electroporation. Diverse electroporation conditions were applied to Lactobacillus delbrueckii ssp. bulgaricus sp1.1 cells exposed to 10% trehalose prior to spray drying with 30% re-constituted skimmed milk. Survival rates of spray-dried bacteria increased with an intracellular trehalose content of ≥3.5 µg/107 colony-forming units (CFU) and reached 100% with intracellular trehalose content of 10.1 µg/107 CFU. The application of two electroporation pulses at 2.5 kV/cm helped increase the survival rate of L. bulgaricus from 38% to 61% after spray drying. Membrane damage and pore formation caused by excessive pulsed electric field treatment resulted in cell death after spray drying. Sufficient intracellular trehalose protected cell walls and membranes from further damage by spray drying. Multi-pulse electroporation of trehalose into lactic acid bacteria prior to spray drying can potentially increase cell viability.