Lactic acid bacteria and bifidobacteria attenuate the proinflammatory response in intestinal epithelial cells induced by Salmonella enterica serovar Typhimurium

Effects of Lactobacillus rhamnosus DSM7133 on Intestinal Porcine Epithelial Cells

Antimicrobial resistance is one of the biggest health challenges nowadays. Probiotics are promising candidates as feed additives contributing to the health of the gastrointestinal tract. The beneficial effect of probiotics is species/strain specific; the potential benefits need to be individually assessed for each probiotic strain or species. We established a co-culture model, in which gastrointestinal infection was modeled using Escherichia coli (E. coli) and Salmonella enterica serovar Typhimurium (S. enterica serovar Typhimurium). Using intestinal porcine epithelial cells (IPEC-J2), the effects of pre-, co-, and post-treatment with Lactobacillus (L.) rhamnosus on the barrier function, intracellular (IC) reactive oxygen species (ROS) production, proinflammatory cytokine (IL-6 and IL-8) response, and adhesion inhibition were tested. E. coli- and S. Typhimurium-induced barrier impairment and increased ROS production could be counteracted using L. rhamnosus (p < 0.01). S. Typhimurium-induced IL-6 production was reduced via pre-treatment (p < 0.05) and post-treatment (p < 0.01); increased IL-8 secretion was decreased via pre-, co-, and post-treatment (p < 0.01) with L. rhamnosus. L. rhamnosus demonstrated significant inhibition of adhesion for both S. Typhimurium (p < 0.001) and E. coli (p < 0.001 in both pre-treatment and post-treatment; p < 0.05 in co-treatment). This study makes a substantial contribution to the understanding of the specific benefits of L. rhamnosus. Our findings can serve as a basis for further in vivo studies carried out in pigs and humans.

Effects of Bacillus licheniformis and Bacillus subtilis on Gut Barrier Function, Proinflammatory Response, ROS Production and Pathogen Inhibition Properties in IPEC-J2—Escherichia coli/Salmonella Typhimurium Co-Culture

The emergence of antimicrobial resistance raises serious concerns worldwide. Probiotics offer a promising alternative to enhance growth promotion in farm animals; however, their mode of action still needs to be elucidated. The IPEC-J2 cell line (porcine intestinal epithelial cells) is an appropriate tool to study the effect of probiotics on intestinal epithelial cells. In our experiments, IPEC-J2 cells were challenged by two gastrointestinal (GI) infection causing agents, Escherichia coli (E. coli) or Salmonella enterica ser. Typhimurium (S. Typhimurium). We focused on determining the effect of pre-, co-, and post-treatment with two probiotic candidates, Bacillus licheniformis or Bacillus subtilis, on the barrier function, proinflammatory cytokine (IL-6 and IL-8) response, and intracellular reactive oxygen species (ROS) production of IPEC-J2 cells, in addition to the adhesion inhibition effect. Bacillus licheniformis (B. licheniformis) and Bacillus subtilis (B. subtilis) proved to be anti-inflammatory and had an antioxidant effect under certain treatment combinations, and further effectively inhibited the adhesion of pathogenic bacteria. Interestingly, they had little effect on paracellular permeability. Based on our results, Bacillus licheniformis and Bacillus subtilis are both promising candidates to contribute to the beneficial effects of probiotic multispecies mixtures.

The Game for Three: Salmonella–Host–Microbiota Interaction Models

Colonization of the gastrointestinal (GI) tract by enteric pathogens occurs in a context strongly determined by host-specific gut microbiota, which can significantly affect the outcome of infection. The complex gameplay between the trillions of microbes that inhabit the GI tract, the host, and the infecting pathogen defines a specific triangle of interaction; therefore, a complete model of infection should consider all of these elements. Many different infection models have been developed to explain the complexity of these interactions. This review sheds light on current knowledge, along with the strengths and limitations of in vitro and in vivo models utilized in the study of Salmonella–host–microbiome interactions. These models range from the simplest experiment simulating environmental conditions using dedicated growth media through in vitro interaction with cell lines and 3-D organoid structure, and sophisticated “gut on a chip” systems, ending in various animal models. Finally, the challenges facing this field of research and the important future directions are outlined.

Effect of Enterococcus faecium NCIMB 10415 on Gut Barrier Function, Internal Redox State, Proinflammatory Response and Pathogen Inhibition Properties in Porcine Intestinal Epithelial Cells

In farm animals, intestinal diseases caused by Salmonella spp. and Escherichia coli may lead to significant economic loss. In the past few decades, the swine industry has largely relied on the prophylactic use of antibiotics to control gastrointestinal diseases. The development of antibiotic resistance has become an important issue both in animal and human health. The use of antibiotics for prophylactic purposes has been banned, moreover the new EU regulations further restrict the application of antibiotics in veterinary use. The swine industry seeks alternatives that are capable of maintaining the health of the gastrointestinal tract. Probiotics offer a promising alternative; however, their mode of action is not fully understood. In our experiments, porcine intestinal epithelial cells (IPEC-J2 cells) were challenged by Salmonella Typhimurium or Escherichia coli and we aimed at determining the effect of pre-, co-, and post-treatment with Enterococcus faecium NCIMB 10415 on the internal redox state, paracellular permeability, IL-6 and IL-8 secretion of IPEC-J2 cells. Moreover, the adhesion inhibition effect was also investigated. Enterococcus faecium was able to reduce oxidative stress and paracellular permeability of IPEC-J2 cells and could inhibit the adhesion of Salmonella Typhimurium and Escherichia coli. Based on our results, Enterococcus faecium is a promising candidate to maintain the health of the gastrointestinal tract.

GAPDH siRNA Regulates SH-SY5Y Cell Apoptosis Induced by Exogenous α-Synuclein Protein

The transport mechanism of intestinal α-synuclein to the central nervous system has become a new hot topic in Parkinson's disease (PD) research. It is worth noting that the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has been reported to be involved in the pathogenesis of PD. After silencing GAPDH expression by GAPDH siRNA, the normal human intestinal epithelial crypt-like (HIEC) and human SH-SY5Y neuroblastoma cell lines were co-cultured with Escherichia coli cells which were transfected with an α-synuclein overexpression plasmid. The levels of autophagy-related proteins (BECN1, ATG5, LC3A/B and p62) were determined by Western blot analysis. Changes in pro-apoptosis protein levels and flow cytometry analysis were used to assess cell apoptosis and relative intracellular ATP concentration was measured. Oxidative stress was assessed by measuring the levels of reactive oxygen species (ROS) using 2',7'-dichlorofluorescein diacetate (DCFH-DA), thiobarbituric acid-reactive substances (TBARS), and antioxidant capacity was assessed by measuring the glutathione (GSH) levels and superoxide dismutase (SOD) activity. The silencing of the expression of GAPDH pre-knockdown was found to reduce the intracellular levels of ROS and lipid peroxidation, enhance autophagy activity, thereby reducing the cell injury, apoptosis and necrosis induced by exogenous α-synuclein protein in SH-SY5Y cells. This study identifies a new therapeutic target of exogenous α-synuclein protein induced SH-SY5Y cell injury and improves our understanding of the pathophysiological role of GAPDH in vitro.

Health-Promoting Role of Lactiplantibacillus plantarum Isolated from Fermented Foods

Fermentation processes have been used for centuries for food production and preservation. Besides the contribution of fermentation to food quality, recently, scientific interest in the beneficial nature of fermented foods as a reservoir of probiotic candidates is increasing. Fermented food microbes are gaining attention for their health-promoting potential and for being genetically related to human probiotic bacteria. Among them, Lactiplantibacillus (Lpb.) plantarum strains, with a long history in the food industry as starter cultures in the production of a wide variety of fermented foods, are being investigated for their beneficial properties which are similar to those of probiotic strains, and they are also applied in clinical interventions. Food-associated Lpb. plantarum showed a good adaptation and adhesion ability in the gastro-intestinal tract and the potential to affect host health through various beneficial activities, e.g., antimicrobial, antioxidative, antigenotoxic, anti-inflammatory and immunomodulatory, in several in vitro and in vivo studies. This review provides an overview of fermented-associated Lpb. plantarum health benefits with evidence from clinical studies. Probiotic criteria that fermented-associated microbes need to fulfil are also reported.

Supplementation of postbiotic RI11 improves antioxidant enzyme activity, upregulated gut barrier genes, and reduced cytokine, acute phase protein, and heat shock protein 70 gene expression levels in heat-stressed broilers

The aim of this work was to evaluate the impacts of feeding different levels of postbiotic RI11 on antioxidant enzyme activity, physiological stress indicators, and cytokine and gut barrier gene expression in broilers under heat stress. A total of 252 male broilers Cobb 500 were allocated in cages in environmentally controlled chambers. All the broilers received the same basal diet from 1 to 21 d. On day 22, the broilers were weighed and grouped into 7 treatment groups and exhibited to cyclic high temperature at 36 ± 1°C for 3 h per day until the end of the experiment. From day 22 to 42, broilers were fed with one of the 7 following diets: negative control, basal diet (0.0% RI11) (NC group); positive control, NC diet + 0.02% (w/w) oxytetracycline (OTC group); antioxidant control, NC diet + 0.02% (w/w) ascorbic acid. The other 4 other groups were as follows: NC diet + 0.2% cell-free supernatant (postbiotic RI11) (v/w), NC diet + 0.4% cell-free supernatant (postbiotic RI11) (v/w), NC diet + 0.6% cell-free supernatant (postbiotic RI11) (v/w), and NC diet + 0.8% cell-free supernatant (postbiotic RI11) (v/w). Supplementation of different levels (0.4, 0.6, and 0.8%) of postbiotic RI11 increased plasma glutathione peroxidase, catalase, and glutathione enzyme activity. Postbiotic RI11 groups particularly at levels of 0.4 and 0.6% upregulated the mRNA expression of IL-10 and downregulated the IL-8, tumor necrosis factor alpha, heat shock protein 70, and alpha-1-acid glycoprotein levels compared with the NC and OTC groups. Feeding postbiotic RI11, particularly at the level of 0.6%, upregulated ileum zonula occludens-1 and mucin 2 mRNA expressions. However, no difference was observed in ileum claudin 1, ceruloplasmin, IL-6, IL-2, and interferon expression, but downregulation of occludin expression was observed as compared with the NC group. Supplementation of postbiotic RI11 at different levels quadratically increased plasma glutathione peroxidase, catalase and glutathione, IL-10, mucin 2, and zonula occludens-1 mRNA expression and reduced plasma IL-8, tumor necrosis factor alpha, alpha-1-acid glycoprotein, and heat shock protein 70 mRNA expression. The results suggested that postbiotics produced from Lactiplantibacillus plantarum RI11 especially at the level of 0.6% (v/w) could be used as an alternative to antibiotics and natural sources of antioxidants in poultry feeding.

The Impact of Probiotics and Egg Yolk IgY on Behavior and Blood Parameters in a Broiler Immune Stress Model

Feed additives are used frequently in variable combinations to maximize broiler productivity and consumer safety. Therefore, we evaluated the efficiency of feed additives used in four different diets: a basal diet, a probiotic (PRO-PAC^®) supplement diet, an egg yolk purified immunoglobulin Y (IgY) supplemented diet, and a combination of IgY and PRO-PAC^® supplement (n = 15 for each group). We assessed the improvement of behavioral and hematological parameters of Ross broilers before and after an immune stress challenge using lipopolysaccharide (LPS). Behavioral as well as physiological parameters were analyzed. The standing frequency was the highest (P < 0.05) in broilers supplemented with a combination of probiotics and IgY. Likewise, latency approach score to a novel object improved (P < 0.01) in the combination group at week-3. After intraperitoneal injection of LPS, this combination group achieved the best gait score at week-3, followed by week-5, compared to birds fed the basal diet. The heterophil/lymphocyte (H/L) ratio, heterophil differential count, and eosinophil differential count in the basal diet group that was challenged with LPS were significantly increased (P < 0.01, P < 0.001, P < 0.05, respectively) compared to the combination groups. Therefore, we concluded that the combination of IgY and probiotics can significantly improve the behavior and the underlying physiological parameters of Ross broilers. Consequently, this combination can improve the broilers′ health, welfare and produce a safe meat free from harmful chemical residues.

Investigating the Proteomic Profile of HT-29 Colon Cancer Cells After Lactobacillus kefiri SGL 13 Exposure Using the SWATH Method

Despite some studies revealed that kefir acts on different cancers, such as colorectal cancer, the proteomic changes that occur in the colon cancer cells remain to be explored. In this study, the proteomic analysis was combined with determination of kefir characteristics (e.g., adhesion capacity, gastrointestinal and antibiotic resistances), in order to confirm its use as a probiotic. Therefore, a label-free strategy based on SWATH-MS was applied to investigate the proteomic profile of HT-29 cells after exposure for 24 h to a specific strain of Lactobacillus kefiri named SGL 13. We identified a total of 60 differentially expressed proteins in HT-29 cells, among which most are located into the extracellular exosome, playing important/crucial roles in translation and cell adhesion, as indicated by the enrichment analysis. The eIF2 and retinoid X receptor activation pathways appeared to be correlated with the anti-tumoral effect of SGL 13. Immunoblot analysis showed an increase in Bax and a decrease in caspase 3 and mutant p53, and ELISA assay revealed inhibition of IL-8 secretion from HT-29 cells stimulated with LPS upon SGL 13 treatment, suggesting pro-apoptotic and anti-inflammatory properties of kefir. In conclusion, the results of this study, the first of its kind using co-culture of kefir and colon cancer cells, demonstrate that L. kefiri SGL 13 possesses probiotic potency and contribute to elucidate the molecular mechanisms involved in the L. kefiri-colon cancer cell interactions.

Analysis of Health Benefits Conferred by Lactobacillus Species from Kefir

Lactobacilli are among the most common microorganisms found in kefir; a traditional fermented milk beverage produced locally in many locations around the world. Kefir has been associated with a wide range of purported health benefits; such as antimicrobial activity; cholesterol metabolism; immunomodulation; anti-oxidative effects; anti-diabetic effects; anti-allergenic effects; and tumor suppression. This review critically examines and assesses these claimed benefits and mechanisms with regard to particular Lactobacillus species and/or strains that have been derived from kefir; as well as detailing further potential avenues for experimentation.

Suppression of Intestinal Epithelial Cell Chemokine Production by Lactobacillus rhamnosus R0011 and Lactobacillus helveticus R0389 Is Mediated by Secreted Bioactive Molecules

Host intestinal epithelial cells (IEC) present at the gastrointestinal interface are exposed to pathogenic and non-pathogenic bacteria and their products. Certain probiotic lactic acid bacteria (LAB) have been associated with a range of host-immune modulatory activities including down-regulation of pro-inflammatory gene expression and cytokine production by IEC, with growing evidence suggesting that these bacteria secrete bioactive molecules with immunomodulatory activity. The aim of this study was to determine whether two lactobacilli with immunomodulatory activity [Lactobacillus rhamnosus R0011 (Lr) and Lactobacillus helveticus R0389 (Lh)], produce soluble mediators able to influence IEC responses to Pattern Recognition Receptor (PRR) ligands and pro-inflammatory cytokines [Tumor Necrosis Factor α (TNFα), Interleukin-1β (IL-1β)], signals inducing IEC chemokine production during infection. To this end, the effects of cell-free supernatants (CFS) from Lr and Lh on IEC production of the pro-inflammatory chemokines interleukin (IL)-8 and cytokine-induced neutrophil chemoattractant 1 (CINC-1) induced by a range of host- or pathogen-derived pro-inflammatory stimuli were determined, and the impact on human HT-29 IEC and a primary IEC line (rat IEC-6) was compared. The Lr-CFS and Lh-CFS did not significantly modulate basal IL-8 production from HT-29 IECs or CINC-1 production from IEC-6 cells. However, both Lr-CFS and Lh-CFS significantly down-regulated IL-8 production from HT-29 IECs challenged with varied PRR ligands. Lr-CFS and Lh-CFS had differential effects on PRR-induced CINC-1 production by rat IEC-6 IECs, with no significant down-regulation of CINC-1 observed from IEC-6 IECs cultured with Lh-CFS. Further analysis of the Lr-CFS revealed down-regulation of IL-8 production induced by the pro-inflammatory cytokines IL-1β and TNFα Preliminary characterization of the bioactive constituent(s) of the Lr-CFS indicates that it is resistant to treatment with DNase, RNase, and an acidic protease, but is sensitive to alterations in pH. Taken together, these results indicate that these lactobacilli secrete bioactive molecules of low molecular weight that may modulate host innate immune activity through interactions with IEC.

Orally administered heat-killed Lactobacillus paracasei MCC1849 enhances antigen-specific IgA secretion and induces follicular helper T cells in mice

Antigen-specific immunoglobulin (Ig) A plays a major role in host defense against infections in gut mucosal tissue. Follicular helper T (Tfh) cells are located in germinal centers and promote IgA production via interactions with germinal center B cells. Several studies have demonstrated that some lactic acid bacteria (LAB) strains activate the host’s acquired immune system, inducing IgA secretion in the intestine. However, the precise molecular mechanisms underlying the effects of LAB on IgA production and Tfh cells are not fully resolved. Lactobacillus paracasei MCC1849 is a probiotic strain isolated from the intestine of a healthy adult. In this study, we investigated the effects of orally administered heat-killed MCC1849 on IgA production in the intestine and on Tfh cell induction in vivo. We found that orally administered MCC1849 induced antigen-specific IgA production in the small intestine, serum and lungs. We also observed that MCC1849 increased the proportion of IgA⁺ B cells and Tfh cells in Peyer’s patches (PPs). In addition, MCC1849 increased the gene expression of IL-12p40, IL-10, IL-21, STAT4 and Bcl-6 associated with Tfh cell differentiation. These results suggest that orally administered MCC1849 enhances antigen-specific IgA production and likely affects Tfh cell differentiation in PPs.

High Molecular Weight Polymer Promotes Bone Health and Prevents Bone Loss Under Salmonella Challenge in Broiler Chickens

As a consequence of rapid growth, broiler chickens are more susceptible to infection as well as bone fractures that result in birds being culled. Intestinal infection/inflammation has been demonstrated to promote bone loss in mice and humans. Given this link, we hypothesize that therapeutics that target the gut can benefit bone health. To test this, we infected broiler chickens (7 days old) with Salmonella and treated the birds with or without MDY, a non-absorbable mucus supplement known to benefit intestinal health, from day 1–21 or from day 14–21. Chicken femoral trabecular and cortical bone parameters were analyzed by microcomputed tomography at 21 days. Birds infected with Salmonella displayed significant trabecular bone loss and bone microarchitecture abnormalities that were specific to the femoral neck region, a common site of fracture in chickens. Histological analyses of the chicken bone indicated an increase in osteoclast surface/bone surface in this area indicating that infection-induced bone resorption likely causes the bone loss. Of great interest, treatment with MDY effectively prevented broiler chicken bone loss and architectural changes when given chronically throughout the experiment or for only a week after infection. The latter suggests that MDY may not only prevent bone loss but reverse bone loss. MDY also increased cortical bone mineral density in Salmonella-treated chickens. Taken together, our studies demonstrate that Salmonella-induced bone loss in broiler chickens is prevented by oral MDY.

Does Modification of the Large Intestinal Microbiome Contribute to the Anti-Inflammatory Activity of Fermentable Fiber?

Fiber is an inadequately understood and insufficiently consumed nutrient. This review examines the possible causal relation between fiber-induced microbiome changes and the anti-inflammatory activity of fiber. To demonstrate the dominant role of fermentable plant fiber in shaping the intestinal microbiome, animal and human fiber-feeding studies are reviewed. Using culture-, PCR-, and sequencing-based microbial analyses, a higher prevalence of Bifidobacterium and Lactobacillus genera was observed from the feeding of different types of fermentable fiber. This finding was reported in studies performed on several host species including human. Health conditions and medications that are linked to intestinal microbial alterations likely also change the nutrient environment of the large intestine. The unique gene clusters of Bifidobacterium and Lactobacillus that enable the catabolism of plant glycans and the ability of Bifidobacterium and Lactobacillus to reduce the colonization of proteobacteria probably contribute to their prevalence in a fiber-rich intestinal environment. The fiber-induced microbiome changes could contribute to the anti-inflammatory activity of fiber. Although most studies did not measure fecal microbial density or total daily fecal microbial output (colon microbial load), limited evidence suggests that the increase in intestinal commensal microbial load plays an important role in the anti-inflammatory activity of fiber. Various probiotic supplements, including Bifidobacterium and Lactobacillus, showed anti-inflammatory activity only in the presence of fiber, which promoted microbial growth as indicated by increasing plasma short-chain fatty acids. Probiotics alone or pure fiber administered under sterile conditions showed no anti-inflammatory activity. The potential mechanisms that could mediate the anti-inflammatory effect of common microbial metabolites are reviewed, but more in vivo trials are needed. Future studies including simultaneous microbial composition and load measurements are also important.

Dual Effects of Cell Free Supernatants from Lactobacillus acidophilus and Lactobacillus rhamnosus GG in Regulation of MMP-9 by Up-Regulating TIMP-1 and Down-Regulating CD147 in PMADifferentiated THP-1 Cells

Objective

Recent studies have reported dysregulated expression of matrix metalloproteinases (MMPs), especially MMP-2, MMP-9, tissue inhibitor of metalloproteinase-1, -2 (TIMP-1, TIMP-2), and extracellular matrix metalloproteinase inducer (EMMPRIN/CD147) in activated macrophages of patients with inflammatory diseases. Therefore, MMP-2, MMP-9, and their regulators may represent a new target for treatment of inflammatory diseases. Probiotics, which are comprised of lactic acid bacteria, have the potential to modulate inflammatory responses. In this experimental study, we investigated the anti-inflammatory effects of cell-free supernatants (CFS) from Lactobacillus acidophilus (L. acidophilus) and L. rhamnosus GG (LGG) in phorbol myristate acetate (PMA)-differentiated THP-1 cells.

Materials and Methods

In this experimental study, PMA-differentiated THP-1 cells were treated with CFS from L. acidophilus, LGG and uninoculated bacterial growth media (as a control). The expression of MMP-2, MMP-9, TIMP-1, and TIMP-2 mRNAs were determined using real-time quantitative reverse transcription polymerase chain reaction (RT- PCR). The levels of cellular surface expression of CD147 were assessed by flow cytometry, and the gelatinolytic activity of MMP-2 and MMP-9 were determined by zymography.

Results

Our results showed that CFS from both L. acidophilus and LGG significantly inhibited the gene expression of MMP-9 (P=0.0011 and P=0.0005, respectively), increased the expression of TIMP-1 (P<0.0001), decreased the cell surface expression of CD147 (P=0.0307 and P=0.0054, respectively), and inhibited the gelatinolytic activity of MMP-9 (P=0.0003 and P<0.0001, respectively) in PMA-differentiated THP-1 cells. Although, MMP-2 expression and activity and TIMP-2 expression remained unchanged.

Conclusion

Our results indicate that CFS from L. acidophilus and LGG possess anti-inflammatory properties and can modulate the inflammatory response.

Lactobacillus fermentum IM12 attenuates inflammation in mice by inhibiting NF-κB-STAT3 signalling pathway

In the present study, we isolated Lactobacillus fermentum IM12 from human gut microbiota, which strongly inhibited interleukin (IL)-6 expression and STAT3 activation in lipopolysaccharide (LPS)-stimulated murine peritoneal macrophages, and examined its anti-inflammatory effect in mice with carrageenan-induced hind-paw oedema (CIE) or 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis (TIC). Oral administration of IM12 (0.2×109, 1×109 or 5×109 cfu/mouse, once a day for 3 days) in mice with CIE significantly suppressed the increase of oedema volume and thickness, as well as myeloperoxidase activity and IL-6, IL-17, NO, and prostaglandin E2 levels in the carrageenan-stimulated paw. Treatment with IM12 (1×109 cfu/mouse, once a day for 3 days) in mice with TIC significantly suppressed colon shortening, and myeloperoxidase activity and IL-6 and IL-17 levels. Treatment with IM12 in mice with CIE or TIC also suppressed the expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2, as well as activation of nuclear factor kappa beta (NF-κB) and signal transducer and activator of transcription 3 (STAT3). Furthermore, IM12 significantly inhibited the expression of iNOS, and COX-2, as well as activation of NF-κB in LPS-stimulated mouse peritoneal macrophages. The inflammatory effect of heat-inactivated IM12 was significantly different to that of live IM12 in mice with TIC, although anti-inflammatory effect of IM12 was reduced by heat treatment. Based on these findings, IM12 may attenuate inflammation by inhibiting NF-κB-STAT3 signalling pathway.

Deleterious Metabolic Effects of High Fructose Intake: The Preventive Effect of Lactobacillus kefiri Administration

Modern lifestyle and diets have been associated with metabolic disorders and an imbalance in the normal gut microbiota. Probiotics are widely known for their health beneficial properties targeting the gut microbial ecosystem. The aim of our study was to evaluate the preventive effect of Lactobacillus kefiri (L. kefiri) administration in a fructose-rich diet (FRD) mice model. Mice were provided with tap water or fructose-added (20% w/v) drinking water supplemented or not with L. kefiri. Results showed that probiotic administration prevented weight gain and epidydimal adipose tissue (EAT) expansion, with partial reversion of the adipocyte hypertrophy developed by FRD. Moreover, the probiotic prevented the increase of plasma triglycerides and leptin, together with the liver triglyceride content. Leptin adipocyte secretion was also improved by L. kefiri, being able to respond to an insulin stimulus. Glucose intolerance was partially prevented by L. kefiri treatment (GTT) and local inflammation (TNFα; IL1β; IL6 and INFγ) was completely inhibited in EAT. L. kefiri supplementation generated an impact on gut microbiota composition, changing Bacteroidetes and Firmicutes profiles. Overall, our results indicate that the administration of probiotics prevents the deleterious effects of FRD intake and should therefore be promoted to improve metabolic disorders.

Dietary Bacillus subtilis-based direct-fed microbials alleviate LPS-induced intestinal immunological stress and improve intestinal barrier gene expression in commercial broiler chickens

This study investigated the effects of Bacillus subtilis-based probiotics on the performance, modulation of host inflammatory responses and intestinal barrier gene expression of broilers subjected to LPS challenge. Chickens were randomly allocated to one of the 3 dietary treatment groups - control, antibiotic, or probiotic. At 14days, half of the chickens in each treatment were injected with LPS (1mg/kg body weight), and the other half injected with sterile PBS. Chickens fed probiotics weighed significantly more than controls at 15days of age, irrespective of immune challenge. LPS challenge significantly reduced weight gain at 24h post-injection, and the probiotics did not alleviate the LPS-induced reduction of weight gain. Serum α-1-AGP levels were significantly higher in LPS-injected chickens, and probiotic supplementation significantly reduced their levels. The percentages of CD4+ lymphocytes were significantly increased in probiotic groups in the absence of immunological challenge but were reduced during LPS challenge compared to controls. CD8+ lymphocytes were significantly reduced in probiotic-fed birds. The LPS-induced increase in the expression of cytokines IL8 and TNFSF15 was reduced by probiotic supplementation, and IL17F, iNOS expression was found to be significantly elevated in probiotic-fed birds subjected to LPS challenge. The reduced gene expression of tight junction proteins (JAM2, occludin and ZO1) and MUC2 induced by LPS challenge was reversed by probiotic supplementation. The results indicate that B. subtilis-based probiotics differentially regulate intestinal immune and tight junction protein mRNA expression during states of LPS-mediated immunological challenge.

Impact of Enteric Health and Mucosal Permeability on Skeletal Health and Lameness in Poultry

Intestinal barrier leakage and/or altered gut microbial composition has been shown to markedly impact both osteoblast and osteoclast activities, systemically through circulation of gut immune cells and cytokines and locally by causing inflammation of extraintestinal organs such as the liver and bone marrow. Mild cases of heightened intestinal inflammation can cause bone loss in male mice in the absence of any overt nutritional deficiencies or weight loss, which has also been shown in chickens that have been infected with Salmonella. For poultry, ingredients selected for feed formulation have also a significant impact on gut health, intestinal microbiota, bone quality, and performance parameters. Consumption of diets with a high content of soluble non-starch polysaccharides (NSP) can affect bone quality parameters by reducing the amount of conjugated bile acids in the intestine, therefore diminishing the absorption of fat-soluble vitamins such as vitamin D and minerals like calcium and phosphorus. Recent enteric inflammation studies have shown that high NSP-containing diets have effects on intestinal viscosity, bone mineral content, and breaking strength, along with increased fluorescein isothiocyanate-dextran (FITC-d) leakage. Other skeletal diseases, such as bacterial chondronecrosis with osteomyelitis and enterococcal spondylitis, have a microbial component that is associated with increased mucosal permeability of the gut. Probiotics targeted toward control of enteric inflammation, either created through infectious disease or poor diet, may serve as a strategy for control of predisposing factors that lead to bone disorders.

Enterococcus faecium HDRsEf1 Protects the Intestinal Epithelium and Attenuates ETEC-Induced IL-8 Secretion in Enterocytes

The probiotic Enterococcus faecium HDRsEf1 (Ef1) has been shown to have positive effects on piglet diarrhoea, but the mechanism has not yet been elucidated. In this study, using the IPEC-J2 cell line to mimic intestinal epithelial cells and enterotoxigenic Escherichia coli (ETEC) K88ac as a representative intestinal pathogen, the mechanism underlying Ef1 protection against an enteropathogen was investigated. The results demonstrated that Ef1 was effective in displacing K88ac from the IPEC-J2 cell layer. Moreover, Ef1 and its cell-free supernatant (S-Ef1) modulate IL-8 released by IPEC-J2 cells. Ef1 and its cell-free supernatant showed the potential to protect enterocytes from an acute inflammatory response. In addition, Ef1 and its cell-free supernatant increased the transepithelial electrical resistance (TEER) of the enterocyte monolayer, thus strengthening the intestinal barrier against ETEC. These results may contribute to the development of therapeutic interventions using Ef1 in intestinal disorders of piglets.

Immunomodulatory Effects of Lactobacillus plantarum Lp62 on Intestinal Epithelial and Mononuclear Cells

Probiotic lactic acid bacteria are known for their ability to modulate the immune system. They have been shown to inhibit inflammation in experiments with animal models, cell culture, and clinical trials. The objective of this study was to elucidate the anti-inflammatory potential of Lactobacillus plantarum Lp62, isolated from cocoa fermentation, in a cell culture model. Lp62 inhibited IL-8 production by Salmonella Typhi-stimulated HT-29 cells and prevented the adhesion of pathogens to these epithelial cells. The probiotic strain was able to modulate TNF-α, IL1-β, and IL-17 secretion by J774 macrophages. J774 activation was reduced by coincubation with Lp62. PBMC culture showed significantly higher levels of CD4⁺CD25⁺ T lymphocytes following treatment with Lp62. Probiotics also induced increased IL-10 secretion by mononuclear cells. L. plantarum Lp62 was able to inhibit inflammatory stimulation in epithelial cells and macrophages and activated a tolerogenic profile in mononuclear cells of healthy donors. These results indicate this strain for a possible application in the treatment or prevention of inflammatory diseases.

Enterococcus faecium NCIMB 10415 modulates epithelial integrity, heat shock protein, and proinflammatory cytokine response in intestinal cells

Probiotics have shown positive effects on gastrointestinal diseases; they have barrier-modulating effects and change the inflammatory response towards pathogens in studies in vitro. The aim of this investigation has been to examine the response of intestinal epithelial cells to Enterococcus faecium NCIMB 10415 (E. faecium), a probiotic positively affecting diarrhea incidence in piglets, and two pathogenic Escherichia coli (E. coli) strains, with specific focus on the probiotic modulation of the response to the pathogenic challenge. Porcine (IPEC-J2) and human (Caco-2) intestinal cells were incubated without bacteria (control), with E. faecium, with enteropathogenic (EPEC) or enterotoxigenic E. coli (ETEC) each alone or in combination with E. faecium. The ETEC strain decreased transepithelial resistance (TER) and increased IL-8 mRNA and protein expression in both cell lines compared with control cells, an effect that could be prevented by pre- and coincubation with E. faecium. Similar effects were observed for the increased expression of heat shock protein 70 in Caco-2 cells. When the cells were challenged by the EPEC strain, no such pattern of changes could be observed. The reduced decrease in TER and the reduction of the proinflammatory and stress response of enterocytes following pathogenic challenge indicate the protective effect of the probiotic.

Impact of kefir derived Lactobacillus kefiri on the mucosal immune response and gut microbiota

The evaluation of the impact of probiotics on host health could help to understand how they can be used in the prevention of diseases. On the basis of our previous studies and in vitro assays on PBMC and Caco-2 ccl20:luc reporter system presented in this work, the strain Lactobacillus kefiri CIDCA 8348 was selected and administrated to healthy Swiss mice daily for 21 days. The probiotic treatment increased IgA in feces and reduced expression of proinflammatory mediators in Peyer Patches and mesenteric lymph nodes, where it also increased IL-10. In ileum IL-10, CXCL-1 and mucin 6 genes were upregulated; meanwhile in colon mucin 4 was induced whereas IFN-γ, GM-CSF, and IL-1β genes were downregulated. Moreover, ileum and colon explants showed the anti-inflammatory effect of L. kefiri since the LPS-induced increment of IL-6 and GM-CSF levels in control mice was significantly attenuated in L. kefiri treated mice. Regarding fecal microbiota, DGGE profiles allowed differentiation of experimental groups in two separated clusters. Quantitative PCR analysis of different bacterial groups revealed only significant changes in Lactobacillus population. In conclusion, L. kefiri is a good candidate to be used in gut inflammatory disorders.

Diet type dictates the gut microbiota and the immune response against Yersinia ruckeri in rainbow trout (Oncorhynchus mykiss)

This study investigated the influence of the rainbow trout (Oncorhynchus mykiss) commensal intestinal microbiota in connection to an experimental Yersina ruckeri infection, the causative agent of enteric redmouth disease. One marine and one plant diet was administered to two different groups of rainbow trout. The plant-based diet gave rise to an intestinal microbiota dominated by the genera Streptococcus, Leuconostoc and Weissella from phylum Firmicutes whereas phylum Proteobacteria/Bacteroidetes/Actinobacteria dominated the community in the marine fed fish. In connection to the Y. ruckeri bath challenge there was no effect of the diet type on the cumulative survival, but the number of Y. ruckeri positive fish as measured by plate count and the number of fish with a 'high' number of reads belonging to genus Yersinia as measured by 16S rRNA next-generation sequencing was higher for marine diet fed fish. Furthermore, the two experimental groups of fish showed a differential immune response, where Y. ruckeri challenged marine fed fish had a higher transcription of IL-1β and MBL-2 relative to challenged plant diet fed fish. The data suggest that the plant diet gave rise to a prebiotic effect favouring the presence of bacterial taxons proving protective in connection to bath challenge by Y. ruckeri.

Regulation of toll-like receptors-mediated inflammation by immunobiotics in bovine intestinal epitheliocytes: role of signaling pathways and negative regulators

Intestinal epithelial cells (IECs) detect bacterial and viral associated molecular patterns via germline-encoded pattern-recognition receptors (PRRs) and are responsible for maintaining immune tolerance to the communities of resident commensal bacteria while being also capable to mount immune responses against pathogens. Toll-like receptors (TLRs) are a major class of PRRs expressed on IECs and immune cells, which are involved in the induction of both tolerance and inflammation. In the last decade, experimental and clinical evidence was generated to support the application of probiotics with immunoregulatory capacities (immunobiotics) for the prevention and treatment of several gastrointestinal inflammatory disorders in which TLRs exert a significant role. The majority of these studies were performed in mouse and human cell lines, and despite the growing interest in the bovine immune system due to the economic importance of cattle as livestock, only few studies have been conducted on cattle. In this regard, our group has established a bovine intestinal epithelial (BIE) cell line originally derived from fetal bovine intestinal epitheliocytes and used this cell line to evaluate the impact of immunobiotics in TLR-mediated inflammation. This review aims to summarize the current knowledge of the beneficial effects of immunobiotics in the regulation of intestinal inflammation/infection in cattle. Especially, we discuss the role of TLRs and their negative regulators in both the inflammatory response and the beneficial effects of immunobiotics in bovine IECs. This review article emphasizes the cellular and molecular interactions of immunobiotics with BIE cells through TLRs and gives the scientific basis for the development of immunomodulatory feed for bovine healthy development.

Diversity, ecology and intestinal function of bifidobacteria

The human gastrointestinal tract represents an environment which is a densely populated home for a microbiota that has evolved to positively contribute to host health. At birth the essentially sterile gastrointestinal tract (GIT) is rapidly colonized by microorganisms that originate from the mother and the surrounding environment. Within a short timeframe a microbiota establishes within the (breastfed) infant's GIT where bifidobacteria are among the dominant members, although their numerical dominance disappears following weaning. The numerous health benefits associated with bifidobacteria, and the consequent commercial relevance resulting from their incorporation into functional foods, has led to intensified research aimed at the molecular understanding of claimed probiotic attributes of this genus. In this review we provide the current status on the diversity and ecology of bifidobacteria. In addition, we will discuss the molecular mechanisms that allow this intriguing group of bacteria to colonize and persist in the GIT, so as to facilitate interaction with its host.

Enterococcus faecalis from healthy infants modulates inflammation through MAPK signaling pathways

Colonizing commensal bacteria after birth are required for the proper development of the gastrointestinal tract. It is believed that bacterial colonization pattern in neonatal gut affects gut barrier function and immune system maturation. Studies on the development of faecal microbiota in infants showed that the neonatal gut was first colonized with enterococci followed by other microbiota such as Bifidobacterium. Other studies showed that babies who developed allergy were less often colonized with Enterococcus during the first month of life as compared to healthy infants. Many studies have been conducted to elucidate how bifidobacteria or lactobacilli, some of which are considered probiotic, regulate infant gut immunity. However, fewer studies have been focused on enterococi. In our study, we demonstrate that E. faecalis, isolated from healthy newborns, suppress inflammatory responses activated in vivo and in vitro. We found E. faecalis attenuates proinflammatory cytokine secretions, especially IL-8, through JNK and p38 signaling pathways. This finding shed light on how the first colonizer, E.faecalis, regulates inflammatory responses in the host.