Effects of Lactiplantibacillus plantarum and Lacticaseibacillus paracasei supplementation on the single-cell fecal parasitome in children with celiac disease autoimmunity: a randomized, double-blind placebo-controlled clinical trial.

BACKGROUND: Lactiplantibacillus plantarum HEAL9 and Lacticaseibacillus paracasei 8700:2 positively affect the fecal bacteriome in children with celiac disease autoimmunity after 6 months of supplementation. The aim of the present investigation was to study the effects of Lactiplantibacillus plantarum HEAL9 and Lacticaseibacillus paracasei 8700:2 on the single-cell parasitome, with a primary focus on Blastocystis. METHODS: Stool samples were collected from 78 Swedish children with celiac disease autoimmunity participating in a randomized, double-blind, placebo-controlled clinical trial to either receive a mixture of supplementation with L. plantarum HEAL9 and L. paracasei 8700:2 (n = 38) or placebo (n = 40). A total of 227 stool samples collected at baseline and after 3 and 6 months of intervention, respectively, were retrospectively analyzed for Blastocystis by quantitative real-time PCR and subtyped by massively parallel amplicon sequencing. Other single-cell parasites were detected by untargeted 18S rDNA amplicon sequencing and verified by real-time PCR. The relation between the parasites and the bacteriome community was characterized by using 16S rDNA profiling of the V3-V4 region. RESULTS: Three different single-cell protists were identified, of which the highest prevalence was found for Dientamoeba fragilis (23.1%, 18/78 children), followed by Blastocystis (15.4%, 12/78) and Entamoeba spp. (2.6%, 2/78). The quantity of the protists was stable over time and not affected by probiotic intervention (P = 0.14 for Blastocystis, P = 0.10 for D. fragilis). The positivity of the protists was associated with increased bacteriome diversity (measured by multiple indices, P < 0.03). Bacterial composition was influenced by the presence of the protists: positivity of Blastocystis was inversely associated with Akkermansia (at the levels of the genus as well as its family, order, class and phylum); P < 0.002), Faecalibacterium (P = 0.003) and Romboutsia (P = 0.029); positivity of D. fragilis was inversely associated with families Enterobacteriaceae (P = 0.016) and Coriobacteriaceae (P = 0.022) and genera Flavonifractor (P < 0.001), Faecalibacterium (P = 0.009), Lachnoclostridium (P = 0.029), Ruminococcus (P < 0.001) and Granulicatella (P = 0.018). CONCLUSIONS: The prevalence of single-cell protists is low in children with celiac disease autoimmunity. The colonization was stable regardless of the probiotic intervention and associated with increased diversity of the fecal bacteriome but inversely associated with some beneficial bacteria.

Comparative immunomodulatory effects in mice and in human dendritic cells of five bacterial strains selected for biocontrol of leafy green vegetables.

The market for ready-to eat vegetables is increasing, but unfortunately so do the numbers of food-borne illness outbreaks related to these products. A previous study has identified bacterial strains suitable for biocontrol of leafy green vegetables to reduce the exposure to pathogens in these products. As a tentative safety evaluation, five selected strains (Rhodococcus cerastii MR5x, Bacillus coagulans LMG P-32205, Bacillus coagulans LMG P-32206, Pseudomonas cedrina LMG P-32207 and Pseudomonas punonensis LMG P-32204) were individually compared for immunomodulating effects in mice and in human monocyte-derived dendritic cells (MoDCs). Mice receiving the two B. coagulans strains consistently resemble the immunological response of the normal control, and no, or low, cell activation and pro-inflammatory cytokine expression was observed in MoDCs exposed to B. coagulans strains. However, different responses were seen in the two models for the Gram-negative P. cedrina and the Gram-positive R. cerastii. Moreover, P. punonensis and B. coagulans increased the microbiota diversity in mice as seen by the Shannon-Wiener index. In conclusion, the two strains of B. coagulans showed an immunological response that indicate that they lack pathogenic abilities, thus encouraging further safety evaluation and showing great potential to be used as biocontrol agents on leafy green vegetables.

Effects on Microbiota Composition after Consumption of Quinoa Beverage Fermented by a Novel Xylose-Metabolizing L. plantarum Strain.

Demands for novel lactic acid bacteria with potential to be used as probiotics along with healthy fermented plant-based products increase worldwide. In this study, a novel Lactiplantibacillus plantarum P31891 strain with enzymatic capacity to degrade tannins and ferment xylose was used as starter culture for fermentation of a quinoa-based beverage. The probiotic potential of the selected strain was evaluated in healthy volunteers. Twenty participants consumed the beverage for 14 days; microbiota changes in saliva and faecal samples were analyzed by Terminal Restriction Fragment Length Polymorphism (T-RFLP), Next Generation Sequencing (NGS) and qPCR; and gastrointestinal well-being and digestive symptoms were recorded. The results indicated that the consumption of the beverage with Lactiplantibacillus plantarum P31891 in a probiotic dose (1012 CFU/mL) increased the number of Lactobacillus in the feces but not in saliva. Overall, the bacterial community did not seem to be influenced by the bacterium or by the beverage, as expressed by the diversity indexes, but specific genera were affected, as reflected in changes in amplicon sequence variants. Consequently, Lactiplantibacillus plantarum P31891 showed potential to be categorized as a probiotic strain in the fermented quinoa-based beverage.

Effects of Probiotic Bacteria Lactobacillaceae on the Gut Microbiota in Children With Celiac Disease Autoimmunity: A Placebo-Controlled and Randomized Clinical Trial.

Disturbances of the gut microbiota may influence the development of various autoimmune diseases. This study investigated the effects of supplementations with the probiotic bacteria, Lactiplantibacillus plantarum HEAL9 and Lacticaseibacillus paracasei 8700:2, on the microbial community in children with celiac disease autoimmunity (CDA). The study included 78 genetically predisposed children for celiac disease with elevated levels of tissue transglutaminase autoantibodies (tTGA) signaling for ongoing CDA. Among those children, 38 received a placebo and 40 received the probiotic supplement daily for 6 months. Fecal and plasma samples were collected at baseline and after 3 and 6 months, respectively. The bacterial community was investigated with 16S rRNA gene sequencing and terminal restriction fragment length polymorphism (T-RFLP), and tTGA levels were measured in radiobinding assays. In children that received probiotic supplementation, the relative abundance of Lactobacillaceae increased over time, while it remained unchanged in the placebo group. There was no overall correlation between tTGA levels and bacterial genus except for a positive correlation between Dialister and IgG-tTG in the probiotic group. The abundance of specific bacterial amplicon sequence variant (ASV:s) changed during the study in both groups, indicating that specific bacterial strains might be affected by probiotic supplementation.

Processed meat products with added plant antioxidants affect the microbiota and immune response in C57BL/6JRj mice with cyclically induced chronic inflammation.

Epidemiological studies have found that there is a correlation between red and processed meat consumption and an increased risk of colorectal cancer. There are numerous existing hypotheses on what underlying mechanisms are causative to this correlation, but the results remain unclear. A common hypothesis is that lipid oxidation, which occurs in endogenous lipids and phospholipids in consumed food, are catalyzed by the heme iron in meat. In this study, five pre-selected plant antioxidant preparations (sea buckthorn leaves and sprouts, summer savory leaves, olive polyphenols, onion skin and lyophilized black currant leaves) were added to a meatball type prone to oxidize (pork meat, 20 % fat, 2% salt, deep-fried and after 2 weeks of storage). Pro-inflammatory markers, neutrophil infiltration and microbiota composition were studied after four months in a chronic inflammation model in C57BL6/J female mice. We found that the bacterial diversity index was affected, as well as initial immunological reactions.

Changes in Intestinal Permeability Ex Vivo and Immune Cell Activation by Three Commonly Used Emulsifiers.

Food additives such as emulsifiers are used in increasing quantities in the food industry. The aim of this study was to compare three different emulsifiers (polysorbate 80 (P80), carboxymethyl cellulose (CMC), and ß-lactoglobulin (ß-lac) with regards to their effect on the stimulation of immune cells and intestinal permeability. The immune stimulatory effects were studied in the myeloid cell line MUTZ-3-cells, while the change in intestinal permeability was studied in the Caco-2 cell line and ex vivo in the Ussing chamber system using small intestinal fragments from rats. The tested concentrations of the emulsifiers ranged from 0.02% up to 1%, which are concentrations commonly used in the food industry. The results showed that P80 affected both the myeloid cells and the intestinal permeability more than CMC (p < 0.05) and ß-lac (p < 0.05) at the highest concentration. CMC was found to neither affect the permeability in the intestine nor the MUTZ-3 cells, while ß-lac changed the permeability in the total part of the small intestine in rats. These findings indicate that P80 might be more cytotoxic compared to the other two emulsifiers.

Effects of Lactobacillus plantarum and Lactobacillus paracasei on the Peripheral Immune Response in Children with Celiac Disease Autoimmunity: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

Two Lactobacillus strains have proven anti-inflammatory properties by reducing pro-inflammatory responses to antigens. This randomized double-blind placebo-controlled trial tested the hypothesis that L. plantarum HEAL9 and L. paracasei 8700:2 suppress ongoing celiac disease autoimmunity in genetically at risk children on a gluten-containing diet in a longitudinally screening study for celiac disease. Seventy-eight children with celiac disease autoimmunity participated of whom 40 received 1010 CFU/day of L. plantarum HEAL9 and L. paracasei 8700:2 (probiotic group) and 38 children maltodextrin (placebo group) for six months. Blood samples were drawn at zero, three and six months and phenotyping of peripheral blood lymphocytes and IgA and IgG autoantibodies against tissue transglutaminase (tTG) were measured. In the placebo group, naïve CD45RA+ Th cells decreased (p = 0.002) whereas effector and memory CD45RO+ Th cells increased (p = 0.003). In contrast, populations of cells expressing CD4+CD25highCD45RO+CCR4+ increased in the placebo group (p = 0.001). Changes between the groups were observed for NK cells (p = 0.038) and NKT cells (p = 0.008). Median levels of IgA-tTG decreased more significantly over time in the probiotic (p = 0.013) than in the placebo (p = 0.043) group whereas the opposite was true for IgG-tTG (p = 0.062 respective p = 0.008). In conclusion, daily oral administration of L. plantarum HEAL9 and L. paracasei 8700:2 modulate the peripheral immune response in children with celiac disease autoimmunity.