Probiotic bacteria Bifidobacterium animalis MB5 and Lactobacillus rhamnosus GG protect intestinal Caco-2 cells from the inflammation-associated response induced by enterotoxigenic Escherichia coli K88

Taxonomic and phenotypic analysis of bifidobacteria isolated from IBD patients as potential probiotic strains

BACKGROUND

Inflammatory Bowel Diseases (IBD) are a major public health issue with unclear aetiology. Changes in the composition and functionality of the intestinal microbiota are associated with these pathologies, including the depletion of strict anaerobes such as Feacalibacterium prausnitzii. Less evidence is observed for depletion in other anaerobes, among which bifidobacteria. This study characterized the taxonomic and functional diversity of bifidobacteria isolated from the human intestinal microbiota in active and non-active IBD patients by a culturomics approach and evaluated if these bifidobacteria might be used as probiotics for gut health.

RESULTS

A total of 341 bifidobacteria were isolated from the intestinal microbiota of IBD patients (52 Crohn's disease and 26 ulcerative colitis patients), with a high proportion of Bifidobacterium dentium strains (28% of isolated bifidobacteria). In ulcerative colitis, the major species identified was B. dentium (39% of isolated bifidobacteria), in active and non-active ulcerative colitis. In Crohn's disease, B. adolescentis was the major species isolated from non-active patients (40%), while similar amounts of B. dentium and B. adolescentis were found in active Crohn's disease patients. The relative abundance of B. dentium was increased with age, both in Crohn's disease and ulcerative colitis and active and non-active IBD patients. Antibacterial capacities of bifidobacteria isolated from non-active ulcerative colitis against Escherichia coli LF82 and Salmonella enterica ATCC 14028 were observed more often compared to strains isolated from active ulcerative colitis. Finally, B. longum were retained as strains with the highest probiotic potential as they were the major strains presenting exopolysaccharide synthesis, antibacterial activity, and anti-inflammatory capacities. Antimicrobial activity and EPS synthesis were further correlated to the presence of antimicrobial and EPS gene clusters by in silico analysis.

CONCLUSIONS

Different bifidobacterial taxonomic profiles were identified in the microbiota of IBD patients. The most abundant species were B. dentium, mainly associated to the microbiota of ulcerative colitis patients and B. adolescentis, in the intestinal microbiota of Crohn's disease patients. Additionally, the relative abundance of B. dentium significantly increased with age. Furthermore, this study evidenced that bifidobacteria with probiotic potential (antipathogenic activity, exopolysaccharide production and anti-inflammatory activity), especially B. longum strains, can be isolated from the intestinal microbiota of both active and non-active Crohn's disease and ulcerative colitis patients.

The inhibition mechanism of co-cultured probiotics on biofilm formation of Klebsiella pneumoniae

AIMS

Klebsiella pneumoniae, an important opportunistic pathogen of nosocomial inflection, is known for its ability to form biofilm. The purpose of the current study is to assess how co- or mono-cultured probiotics affect K. pneumoniae's ability to produce biofilms and investigate the potential mechanisms by using a polyester nonwoven chemostat and a Caco-2 cell line.

METHODS AND RESULTS

Compared with pure cultures of Lactobacillus rhamnosus and Lactobacillus sake, the formation of K. pneumoniae biofilm was remarkably inhibited by the mixture of L. rhamnosus, L. sake, and Bacillus subtilis at a ratio of 5:5:1 by means of qPCR and FISH assays. In addition, Lactobacillus in combination with B. subtilis could considerably reduce the adherence of K. pneumoniae to Caco-2 cells by using inhibition, competition, and displacement assays. According to the RT-PCR assay, the adsorption of K. pneumoniae to Caco-2 cells was effectively inhibited by the co-cultured probiotics, leading to significant reduction in the expression of proinflammatory cytokines induced by K. pneumoniae. Furthermore, the HPLC and RT-PCR analyses showed that the co-cultured probiotics were able to successfully prevent the expression of the biofilm-related genes of K. pneumoniae by secreting plenty of organic acids as well as the second signal molecule (c-di-GMP), resulting in inhibition on biofilm formation.

CONCLUSION

Co-culture of L. sake, L. rhamnosus, and B. subtilis at a ratio of 5:5:1 could exert an antagonistic effect on the colonization of pathogenic K. pneumoniae by down-regulating the expression of biofilm-related genes. At the same time, the co-cultured probiotics could effectively inhibit the adhesion of K. pneumoniae to Caco-2 cells and block the expression of proinflammatory cytokines induced by K. pneumoniae.

The microbiota-gut-brain axis: A crucial immunomodulatory pathway for Bifidobacterium animalis subsp. lactis' resilience against LPS treatment in neonatal rats

An imbalanced gut microflora may contribute to immune disorders in neonates due to an immature gut barrier. Bacterial toxins, particularly, can trigger the immune system, potentially resulting in uncontrolled gut and systemic inflammation. Previous research has revealed that Bifidobacterium animalis subsp. lactis (B. lactis) could protect against early-life pathogen infections by enhancing the gut barrier. However, the effects of B. lactis on a compromised immune system remain uncertain. Hence, this study concentrated on the immunomodulatory effects and mechanisms of B. lactis in neonatal rats intraperitoneally injected with lipopolysaccharide (LPS), a bacterial toxin and inflammatory mediator. First, B. lactis significantly alleviated the adverse effects induced by LPS on the growth, development, and body temperature of neonatal rats. Second, B. lactis significantly reduced the immune responses and damage induced by LPS, affecting both systemic and local immune responses in the peripheral blood, gut, and brain. Notably, B. lactis exhibited extra potent neuroprotective and neurorepair effects. Our research found that pre-treatment with B. lactis shaped the diverse gut microecology by altering both microbial populations and metabolic biomolecules, closely linked to immunomodulation. Overall, this study elucidated the multifaceted roles of B. lactis in neonatal hosts against pathogenic infection and immune disorder, revealing the existence of the microbiota-gut-brain axis.

Neutrophils: from IBD to the gut microbiota

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the gastrointestinal tract that results from dysfunction in innate and/or adaptive immune responses. Impaired innate immunity, which leads to lack of control of an altered intestinal microbiota and to activation of the adaptive immune system, promotes a secondary inflammatory response that is responsible for tissue damage. Neutrophils are key players in innate immunity in IBD, but their roles have been neglected compared with those of other immune cells. The latest studies on neutrophils in IBD have revealed unexpected complexities, with heterogeneous populations and dual functions, both deleterious and protective, for the host. In parallel, interconnections between disease development, intestinal microbiota and neutrophils have been highlighted. Numerous IBD susceptibility genes (such as NOD2, NCF4, LRRK2, CARD9) are involved in neutrophil functions related to defence against microorganisms. Moreover, severe monogenic diseases involving dysfunctional neutrophils, including chronic granulomatous disease, are characterized by intestinal inflammation that mimics IBD and by alterations in the intestinal microbiota. This observation demonstrates the dialogue between neutrophils, gut inflammation and the microbiota. Neutrophils affect microbiota composition and function in several ways. In return, microbial factors, including metabolites, regulate neutrophil production and function directly and indirectly. It is crucial to further investigate the diverse roles played by neutrophils in host-microbiota interactions, both at steady state and in inflammatory conditions, to develop new IBD therapies. In this Review, we discuss the roles of neutrophils in IBD, in light of emerging evidence proving strong interconnections between neutrophils and the gut microbiota, especially in an inflammatory context.

Human Intestinal Organoids and Microphysiological Systems for Modeling Radiotoxicity and Assessing Radioprotective Agents

Radiotherapy is a commonly employed treatment for colorectal cancer, yet its radiotoxicity-related impact on healthy tissues raises significant health concerns. This highlights the need to use radioprotective agents to mitigate these side effects. This review presents the current landscape of human translational radiobiology, outlining the limitations of existing models and proposing engineering solutions. We delve into radiotherapy principles, encompassing mechanisms of radiation-induced cell death and its influence on normal and cancerous colorectal cells. Furthermore, we explore the engineering aspects of microphysiological systems to represent radiotherapy-induced gastrointestinal toxicity and how to include the gut microbiota to study its role in treatment failure and success. This review ultimately highlights the main challenges and future pathways in translational research for pelvic radiotherapy-induced toxicity. This is achieved by developing a humanized in vitro model that mimics radiotherapy treatment conditions. An in vitro model should provide in-depth analyses of host-gut microbiota interactions and a deeper understanding of the underlying biological mechanisms of radioprotective food supplements. Additionally, it would be of great value if these models could produce high-throughput data using patient-derived samples to address the lack of human representability to complete clinical trials and improve patients' quality of life.

Risk factors associated with post-weaning diarrhoea in Austrian piglet-producing farms

Post-weaning diarrhoea (PWD) is a frequent, multifactorial disease of piglets leading to increased mortality rates and high economic losses. Due to the emergence of multi-resistant Escherichia coli isolates and the ban of zinc oxide (ZnO) in the EU since June 2022, alternative measures to prevent PWD are urgently needed. While an abundance of feed supplements is described to prevent PWD, there are hardly any studies reflecting the current situation of PWD in the field. Thus, we aimed to identify differences in management practices, housing and feeding strategies between farms with PWD and farms without PWD. Data were personally collected using a semi-structured questionnaire in 257 Austrian piglet-producing farms. Farms with PWD in more than 10% of all weaned groups within twelve months prior to data collection were defined as case farms (n = 101), while the remaining 136 farms were defined as control farms. Data from 237 farms and 69 explanatory variables were analysed via penalized binary logistic regression using elastic-net in 100 different splits into randomly selected training and test datasets (80:20). Treatment with ZnO and/or colistin (136 farms) was negatively associated with PWD in all splits and had the biggest estimated absolute log odds ratio out of all tested variables. Implementation of an all-in/all-out system in the nursery units and administration of probiotics or horseradish also had preventive effects in most splits (≥ 97%). A higher number of feeding phases for piglets within the first seven weeks of life and housing on fully slatted floors was associated negatively with the occurrence of PWD as well in > 95% of all splits. PWD was more likely to occur on farms having problems with neonatal diarrhoea or postpartum dysgalactia syndrome. While our data demonstrate that treatment with ZnO or colistin had the biggest statistical effect on PWD, we were able to identify other preventive measures like supplementation with probiotics or horseradish. Since implementation of all-in/all-out measures and fully slatted floors were also negatively associated with the occurrence of PWD on visited farms, we assume that reduction of bacterial load by the implementation of simple hygiene measures are still crucial to prevent PWD.

Lactiplantibacillus plantarum Strains Modulate Intestinal Innate Immune Response and Increase Resistance to Enterotoxigenic Escherichia coli Infection

Currently, probiotic bacteria with not transferable antibiotic resistance represent a sustainable strategy for the treatment and prevention of enterotoxigenic Escherichia coli (ETEC) in farm animals. Lactiplantibacillus plantarum is among the most versatile species used in the food industry, either as starter cultures or probiotics. In the present work, the immunobiotic potential of L. plantarum CRL681 and CRL1506 was studied to evaluate their capability to improve the resistance to ETEC infection. In vitro studies using porcine intestinal epithelial (PIE) cells and in vivo experiments in mice were undertaken. Expression analysis indicated that both strains were able to trigger IL-6 and IL-8 expression in PIE cells in steady-state conditions. Furthermore, mice orally treated with these strains had significantly improved levels of IFN-γ and TNF-α in the intestine as well as enhanced activity of peritoneal macrophages. The ability of CRL681 and CRL1506 to beneficially modulate intestinal immunity was further evidenced in ETEC-challenge experiments. In vitro, the CRL1506 and CRL681 strains modulated the expression of inflammatory cytokines (IL-6) and chemokines (IL-8, CCL2, CXCL5 and CXCL9) in ETEC-stimulated PIE cells. In vivo experiments demonstrated the ability of both strains to beneficially regulate the immune response against this pathogen. Moreover, the oral treatment of mice with lactic acid bacteria (LAB) strains significantly reduced ETEC counts in jejunum and ileum and prevented the spread of the pathogen to the spleen and liver. Additionally, LAB treated-mice had improved levels of intestinal IL-10 both at steady state and after the challenge with ETEC. The protective effect against ETEC infection was not observed for the non-immunomodulatory TL2677 strain. Furthermore, the study showed that L. plantarum CRL1506 was more efficient than the CRL681 strain to modulate mucosal immunity highlighting the strain specific character of this probiotic activity. Our results suggest that the improved intestinal epithelial defenses and innate immunity induced by L. plantarum CRL1506 and CRL681 would increase the clearance of ETEC and at the same time, protect the host against detrimental inflammation. These constitute valuable features for future probiotic products able to improve the resistance to ETEC infection.

Dairy-Based Probiotic-Fermented Functional Foods: An Update on Their Health-Promoting Properties

Numerous studies have shown a link between the consumption of fermented dairy foods and improved health outcomes. Since the early 2000s, especially probiotic-based fermented functional foods, have had a revival in popularity, mostly as a consequence of claims made about their health benefits. Among them, fermented dairy foods have been associated with obesity prevention and in other conditions such as chronic diarrhea, hypersensitivity, irritable bowel syndrome, Helicobacter pylori infection, lactose intolerance, and gastroenteritis which all are intimately linked with an unhealthy way of life. A malfunctioning inflammatory response may affect the intestinal epithelial barrier’s ability to function by interfering with the normal metabolic processes. In this regard, several studies have shown that fermented dairy probiotics products improve human health by stimulating the growth of good bacteria in the gut at the same time increasing the production of metabolic byproducts. The fermented functional food matrix around probiotic bacteria plays an important role in the survival of these strains by buffering and protecting them from intestinal conditions such as low pH, bile acids, and other harsh conditions. On average, cultured dairy products included higher concentrations of lactic acid bacteria, with some products having as much as 109/mL or g. The focus of this review is on fermented dairy foods and associated probiotic products and their mechanisms of action, including their impact on microbiota and regulation of the immune system. First, we discussed whey and whey-based fermented products, as well as the organisms associated with them. Followed by the role of probiotics, fermented-product-mediated modulation of dendritic cells, natural killer cells, neutrophils, cytokines, immunoglobulins, and reinforcement of gut barrier functions through tight junction. In turn, providing the ample evidence that supports their benefits for gastrointestinal health and related disorders.

Recent Development of Probiotic Bifidobacteria for Treating Human Diseases

Bifidobacterium is a non-spore-forming, Gram-positive, anaerobic probiotic actinobacterium and commonly found in the gut of infants and the uterine region of pregnant mothers. Like all probiotics, Bifidobacteria confer health benefits on the host when administered in adequate amounts, showing multifaceted probiotic effects. Examples include B. bifidum, B. breve, and B. longum, common Bifidobacterium strains employed to prevent and treat gastrointestinal disorders, including intestinal infections and cancers. Herein, we review the latest development in probiotic Bifidobacteria research, including studies on the therapeutic impact of Bifidobacterial species on human health and recent efforts in engineering Bifidobacterium. This review article would provide readers with a wholesome understanding of Bifidobacteria and its potentials to improve human health.

Physicochemical Investigation of Biosynthesis of a Protein Coating on Glass That Promotes Mammalian Cell Growth Using Lactobacillus rhamnosus GG Bacteria

Glass surfaces, although the first to be used for culturing ex vivo adherent cells, are not the perfect substrates for this purpose. Today, plastics dominate these applications, but in light of the global trend to reduce the use of synthetic polymers, it is reasonable to consider a return to glass vessels with coatings for these purposes. The ideal surface for cell growth is one that simulates the composition and structure of the mainly protein-based intercellular matrix. The work presented here shows a new idea of preparing porous protein coatings on glass using biosynthesis. The process utilizes the colonization of the gold nanoparticle-coated glass surface with Lactobacillus rhamnosus GG bacteria, followed by permeabilization (using ethanol) of their membrane and partial thermal degradation (at 160 °C in vacuum) of the surface-bound protein components of these microorganisms. It results in a development of coating on the glass that promotes mammalian cell growth, which has been preliminary confirmed using Vero cells. Subsequent steps in the formation of coating components were documented by reflectance ultraviolet and visible spectra and infrared spectroscopy. The presence of microorganisms and mammalian cells was confirmed using scanning electron and optical microscopy and crystalline violet staining.

Probiotics in Counteracting the Role of Neutrophils in Cancer Metastasis

Neutrophils are known for their role geared towards pathogen clearance by different mechanisms that they initiate, primarily by the release of neutrophil extracellular traps (NETs). However, their immune-surveillance capacity accompanied with plasticity in existing as interchangeable subsets, discovered recently, has revealed their property to contribute to complex cancer pathologies including tumor initiation, growth, angiogenesis and metastasis. Although there is a growing body of evidence suggesting a critical balance between the protumoral and antitumoral neutrophil phenotypes, an in-depth signaling pathway analysis would aid in determination of anticipatory, diagnostic and therapeutic targets. This review presents a comprehensive overview of the potential pathways involved in neutrophil-triggered cancer metastasis and introduces the influence of the microbial load and avenues for probiotic intervention.

Potential probiotic Lacticaseibacillus rhamnosus MTCC-5897 attenuates Escherichia coli induced inflammatory response in intestinal cells

Probiotics are microbes having tremendous potential to prevent gastrointestinal disorders. In current investigation, immunomodulatory action of probiotic Lacticaseibacillus rhamnosus MTCC-5897 was studied during exclusion, competition and displacement of Escherichia coli on intestinal epithelial (Caco-2) cells. The incubation of intestinal cells with Escherichia coli, enhanced downstream signalling and activated nuclear factor kappa B (NF-κB). This significantly increased (p < 0.01) the pro-inflammatory cytokines (IL-8, TNF-α, IFN-ϒ) expression. While, incubation of epithelial cells with Lacticaseibacillus rhamnosus during exclusion and competition with Escherichia coli, counteracted these enhanced expressions. The immunomodulatory feature of Lacticaseibacillus rhamnosus was also highlighted with increased (p < 0.05) transcription of toll-like receptor-2 (TLR-2) and single Ig IL-1-related receptor (SIGIRR) along with diminished expression of TLR-4. Likewise, attenuation (p < 0.05) of E. coli-mediated enhanced nuclear translocation of NF-κB p-65 subunit by Lacticaseibacillus rhamnosus during exclusion was confirmed with western blotting. Thus, present finding establishes the prophylactic potential of Lacticaseibacillus rhamnosus against exclusion of Escherichia coli in intestinal cells.

The anti-inflammatory and antiapoptotic effects of probiotic on induced neurotoxicity in juvenile hamsters

Brain inflammation and apoptosis play crucial roles in the pathogenesis of various neurodevelopmental disorders. Probiotics have been shown to confer protection against many stresses, including apoptosis and inflammation, by modulating the gut function. The short-chain fatty acid, propionic acid (PPA), plays an important intermediate of cellular metabolism. Although PPA exhibits numerous beneficial biological effects, its accumulation is neurotoxic. This study focused on the therapeutic potency of probiotics against PPA-induced apoptosis and neuroinflammation in hamsters. Five groups of male golden Syrian hamsters were treated as follows: Group I as control; Group II as PPA-treated with three doses of 250 mg PPA/kg/day; Group III as clindamycin-treated with a single dose of 30 mg clindamycin/kg; Group IV as PPA-probiotic; and Group V as clindamycin-probiotic were two therapeutic groups which were treated with the same doses of PPA and clindamycin, respectively, followed by treatment with 0.2 g kg-1 d-1 of probiotic (ProtexinR, Probiotics International Limited) for three weeks. Proapoptotic markers, such as caspases 3 and 7; neuroinflammation markers, such as interleukins 1β and 8; and heat shock protein 70 were measured in the brain. Significant increase of all measured markers (p ˂ .001) was observed in PPA and clindamycin-treated hamsters compared with controls. Probiotics significantly reduced the damages and ameliorated all the test markers in both therapeutic groups compared with the control. Our results confirmed that probiotics can be utilized as a feasible strategy for managing apoptotic and inflammation-related stresses in brain disorders by retaining the gut function.

Protective effect of Bifidobacterium bifidum FSDJN7O5 and Bifidobacterium breve FHNFQ23M3 on diarrhea caused by enterotoxigenic Escherichia coli

Enterotoxigenic Escherichia coli (ETEC) is the main bacterial cause of diarrhea among children in developing countries and of traveler's diarrhea. In this study, a mouse model was used to evaluate the effect of Bifidobacterium on alleviating diarrhea caused by ETEC. The results showed that B. breve FHNFQ23M3 and B. bifidum FSDJN7O5 could relieve the symptoms of diarrhea. Both strains significantly reduced the stool water content, restored the villi structure in the jejunum and ameliorated the fecal short-chain fatty acid (SCFA) content. In addition, B. breve FHNFQ23M3 restored body weight to the level before ETEC challenge and significantly reduced interferon-γ (IFN-γ), while B. bifidum FSDJN7O5 significantly improved interleukin (IL)-10. Furthermore, all the Bifidobacterium strains used in this study could significantly downregulate tumor necrosis factor-α (TNF-α) and restore the unbalanced gut microbiota, which had a high content of pathogenic Escherichia-Shigella and low content of Blautia and Clostridium innocuum groups due to ETEC. All the results proved that Bifidobacterium could be a potential probiotic for alleviating diarrhea from ETEC infection.

Evaluation of the probiotic and functional potential of Lactobacillus agilis 32 isolated from pig manure

Escherichia coli is a symbiotic bacterium in humans and animals and an important pathogen of humans and animals. Prevention and suppression of E. coli infection is of great concern. In this study, we isolated a strain of Lactobacillus agilis 32 from pig manure and evaluated its biological characteristics, and found that its bacterial survival rate was 25% after 4 h of treatment at pH 2, and under the condition of 0·5% bile concentration, its survival rate exceeds 30%. In addition, L. agilis 32 has a cell surface hydrophobicity of 77·8%, and exhibits 67·1% auto-aggregation and 63·2% aggregation with Enterotoxigenic E. coli 10 (ETEC 10). FITC fluorescence labelling showed that the fluorescence intensity of cecum was significantly higher than that of duodenum, jejunum or colon (P < 0·05), but no significant difference from ileum. Lactobacillus agilis 32 bacterial culture and CFS showed average inhibition zone diameters of 14·2 and 15·4 mm respectively. Lactobacillus agilis 32 CFS treatment can significantly reduce the pathogenicity of ETEC 10. These results show that L. agilis 32 is an active and potential probiotic, and it has a good antibacterial effect on ETEC10, which provides basic research for probiotics to prevent and treat intestinal diarrhoea pathogen infection.

Dietary inclusion of multispecies probiotics to reduce the severity of post-weaning diarrhea caused by Escherichia coli F18+ in pigs

This study was aimed to determine the efficacy of multispecies probiotics in reducing the severity of post-weaning diarrhea caused by enterotoxigenic Escherichia coli (ETEC) F18⁺ on newly weaned pigs. Thirty-two pigs (16 barrows and 16 gilts, BW = 6.99 ± 0.33 kg) at 21 d of age were individually allotted in a randomized complete block design with 2 × 2 factorial arrangement of treatments. Pigs were selected from sows not infected previously and not vaccinated against ETEC. Pigs were fed experimental diets for 25 d based on 10 d phase 1 and 15 d phase 2. The factors were ETEC challenge (oral inoculation of saline solution or E. coli F18⁺ at 2 × 10⁹ CFU) and probiotics (none or multispecies probiotics 0.15% and 0.10% for phase 1 and 2, respectively). Body weight and feed intake were measured on d 5, 9, 13, 19, and 25. Fecal scores were measured daily. Blood samples were taken on d 19 and 24. On d 25, all pigs were euthanized to obtain samples of digesta, intestinal tissues, and spleen. The tumor necrosis factor alpha (TNFα), malondialdehyde (MDA), peptide YY (PYY), and neuropeptide Y (NPY) were measured in serum and intestinal tissue. Data were analyzed using the MIXED procedure of SAS. The fecal score of pigs was increased (P < 0.05) by ETEC challenge at the post–challenge period. The ETEC challenge decreased (P < 0.05) jejunal villus height and crypt depth, tended to increase (P = 0.056) jejunal TNFα, increased (P < 0.05) ileal crypt depth, and decreased (P < 0.05) serum NPY. The probiotics decreased (P < 0.05) serum TNFα, tended to reduce (P = 0.064) jejunal MDA, tended to increase (P = 0.092) serum PYY, and increased (P < 0.05) jejunal villus height, and especially villus height-to-crypt depth ratio in challenged pigs. Growth performance of pigs were not affected by ETEC challenge, whereas the probiotics increased (P < 0.05) ADG and ADFI and tended to increase (P = 0.069) G:F ratio. In conclusion, ETEC F18⁺ challenge caused diarrhea, intestinal inflammation and morphological damages without affecting the growth performance. The multispecies probiotics enhanced growth performance by reducing intestinal inflammation, oxidative stress, morphological damages.

Towards Zero Zinc Oxide: Feeding Strategies to Manage Post-Weaning Diarrhea in Piglets

Simple Summary

Zinc oxide (ZnO) supplementation at pharmacological doses in post-weaning piglets is a consolidated practice that allows efficient control of post-weaning diarrhea (PWD), a condition exacerbated by Escherichia coli F4 (K88) infections. Far from being completely elucidated, the multifactorial ZnO mechanism of action is in all likelihood exerted at the gastrointestinal level. However, increasing environmental concerns are arising from prolonged ZnO use. This article reviews the utilization of ZnO in piglets, the biological rationale behind its powerful activity, and the emerging threats that are leading towards a significant reduction in its use. Finally, a wide analysis of the strengths and weaknesses of innovative alternative strategies to manage PWD at the nutritional level is given.

Abstract

Zinc oxide (ZnO) at pharmacological doses is extensively employed in the pig industry as an effective tool to manage post-weaning diarrhea (PWD), a condition that causes huge economic losses because of its impact on the most pivotal phase of a piglet’s production cycle. In a multifactorial way, ZnO exerts a variety of positive effects along the entire gastrointestinal tract by targeting intestinal architecture, digestive secretions, antioxidant systems, and immune cells. ZnO also has a moderate antibacterial effect against Escherichia coli F4 (K88), the main causative agent of PWD. However, the environmental impact of ZnO and new emerging threats are posing serious questions to the sustainability of its extensive utilization. To work towards a future free from pharmacological ZnO, novel nutritional approaches are necessary, and many strategies have been investigated. This review article provides a comprehensive framework for ZnO utilization and its broad mode of action. Moreover, all the risks related to pharmacological ZnO levels are presented; we focus on European institutions’ decisions subsequently. The identification of a novel, complete solution against PWD should be accompanied by the adoption of holistic strategies, thereby combining good management practices to feeding approaches capable of mitigating Escherichia coli F4 (K88) infections and/or lowering ZnO utilization. Promising results can be obtained by adjusting diet composition or employing organic acids, natural identical compounds, polyphenol-rich extracts, prebiotics, and probiotics.

Functional in vitro screening of probiotic strains for inoculation of piglets as a prophylactic measure towards Enterotoxigenic Escherichia coli infection

Enterotoxigenic Escherichia coli (ETEC), being the major cause of post-weaning diarrhoea (PWD) in newly weaned piglets, induces poor performance and economic losses in pig production. This functional in vitro screening study investigated probiotic strains for use in suckling piglets as a prophylactic strategy towards PWD. Nine strains were evaluated based on their ability to: enhance intestinal epithelial barrier function, reduce adherence of ETEC F18 to intestinal cells, inhibit growth of ETEC F18, and grow on porcine milk oligosaccharides. Strains included in the screening were of the species Lactobacillus, Enterococcus, Bifidobacterium and Bacillus. Our in vitro screening demonstrated genus-, species and strain-specific differences in the mode of action of the tested probiotic strains. Some of the tested bifidobacteria were able to grow on the two porcine milk oligosaccharides, 3'-sialyllactose sodium salt (3'SL) and Lacto-N-neotetraose (LNnT), whereas most lactic acid bacteria strains and both Bacillus subtilis strains failed to do so. All probiotic strains inhibited growth of ETEC F18 on agar plates. All but the bifidobacteria reduced binding of ETEC F18 to Caco-2 cell monolayers, with the Enterococcus faecium strain having the most profound effect. All three lactic acid bacteria and Bifidobacterium animalis subsp. lactis counteracted the ETEC F18-induced permeability across Caco-2 cell monolayers with the E. faecium strain exhibiting the most pronounced protective effect. The findings from this in vitro screening study indicate that, when selecting probiotic strains for suckling piglets as a prophylactic strategy towards PWD, it would be advantageous to choose a multi-species product including strains with different modes of action in order to increase the likelihood of achieving beneficial effects in vivo.

Celiac disease and reproductive failures: An update on pathogenic mechanisms

Celiac disease (CD) is an autoimmune disorder that occurs in genetically predisposed people in which the ingestion of gluten leads to damage in the small intestine that clinically presents with malabsorption-related symptoms. CD can also be the underlying cause of several non-gastrointestinal symptoms. This review summarizes evidence on the relationship between CD and gynecological/obstetric disorders like reproductive failures. Although much has been reported on such a linkage, the pathogenic mechanisms remain unclear, especially those underlying extra-gastrointestinal clinical manifestations. Studies conducted on celiac subjects presenting gynecological/obstetric disorders have pointed to intestinal malabsorption, coagulation alterations, immune-mediated tissue damage, and endometrial inflammation as the main responsible pathogenic mechanisms. Currently, however, the knowledge of such mechanisms is insufficient, and further studies are needed to gain a more thorough understanding of the matter.

Psychological Stress, Intestinal Barrier Dysfunctions, and Autoimmune Disorders: An Overview

Autoimmune disorders (ADs) are multifactorial diseases involving, genetic, epigenetic, and environmental factors characterized by an inappropriate immune response toward self-antigens. In the past decades, there has been a continuous rise in the incidence of ADs, which cannot be explained by genetic factors alone. Influence of psychological stress on the development or the course of autoimmune disorders has been discussed for a long time. Indeed, based on epidemiological studies, stress has been suggested to precede AD occurrence and to exacerbate symptoms. Furthermore, compiling data showed that most of ADs are associated with gastrointestinal symptoms, that is, microbiota dysbiosis, intestinal hyperpermeability, and intestinal inflammation. Interestingly, social stress (acute or chronic, in adult or in neonate) is a well-described intestinal disrupting factor. Taken together, those observations question a potential role of stress-induced defect of the intestinal barrier in the onset and/or the course of ADs. In this review, we aim to present evidences supporting the hypothesis for a role of stress-induced intestinal barrier disruption in the onset and/or the course of ADs. We will mainly focus on autoimmune type 1 diabetes, multiple sclerosis and systemic lupus erythematosus, ADs for which we could find sufficient circumstantial data to support this hypothesis. We excluded gastrointestinal (GI) ADs like coeliac disease to privilege ADs not focused on intestinal disorders to avoid confounding factors. Indeed, GIADs are characterized by antibodies directed against intestinal barrier actors.

The Development of High-Quality Multispecies Probiotic Formulations: From Bench to Market

Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. To date, there is an increasing number of commercially available products containing probiotics on the market. Probiotics have been recommended by health care professionals for reasons ranging from their long-term immunomodulatory effects to proven benefits in the management of different health conditions. For probiotic products, there are several important aspects that determine the success rate of the development from bench to market. The aim of this review is to explore how the current knowledge on microbe–microbe and host–microbe interactions can be used to develop high-quality, evidence-based probiotic formulations, specifically probiotic dietary supplements, with a focus on the selection of safe strains with relevant functional properties. In addition, we will highlight aspects of the probiotic manufacturing process that need to be considered during the product development and the subsequent manufacturing process to guarantee consistent efficacy of a probiotic product. For each high-quality probiotic formulation, it is important to screen multiple strains, and select only those strains that show relevant functional properties and that can be considered safe for human consumption. In addition, it is imperative that attention is paid to the product development and manufacturing process, and that safety and quality properties are monitored. Importantly, the beneficial effects of probiotics should be evaluated in product efficacy studies and post-marketing surveys in order to demonstrate their clinical efficacy. All these aspects need to be evaluated and validated during the development of a successful high-quality and ready-to-market probiotic.

The Prospects for the Therapeutic Implications of Genetically Engineered Probiotics

The interest in the therapeutic use of probiotic microorganisms has been increased during the last decade although the doubts have ascended about the probiotics mainly because their beneficial effects are not fully understood, and, in many cases, their usefulness has not been validated in clinical trials. Consequently, the notion got a considerable interest in those strains having proven probiotic potential to be engineered for improvement in their beneficial features. The process of genetic engineering can also be used for probiotic strains for the reversion of antimicrobial resistance and other modifications for their safer and effective human applications. The lactic acid bacilli are predominantly opposite as they already have gained attention owing to their health-promoting benefits and their safety for human consumption; therefore, their use, especially as a delivery agent of vaccines and drugs, is gaining attention. The tailoring of probiotic strains will not only improve the data regarding the probiotic potential of these strains but also clinch the doubts concerning these probiotics. This article focuses on the approaches of bioengineered probiotics and discusses the potential prospects for their therapeutic applications including immunomodulation, cognitive health, and anticancer therapeutics.

Lactic acid bacteria decrease Salmonella enterica Javiana virulence and modulate host inflammation during infection of an intestinal epithelial cell line

Salmonella enterica Javiana is a leading cause of severe foodborne Salmonellosis. Despite its emergence as a major foodborne pathogen, little is known of how S. Javiana interacts with intestinal epithelial cells, or of potential methods for ameliorating the bacterial-host interaction. Using cell-based adhesion, invasion and lactate dehydrogenase release assays, we observed an invasive and cytotoxic effect of S. Javiana on intestinal epithelial cells. We assessed the effect of probiotic species of lactic acid bacteria (LAB) on the S. Javiana-host cell interaction, and hypothesized that LAB would reduce S. Javiana infectivity. Salmonella enterica Javiana invasion was significantly impaired in host cells pre-treated with live Lactobacillus acidophilus and Lactobacillus rhamnosus. In addition, pre-exposure of host cells to live L. acidophilus, L. rhamnosus and L. casei reduced S. Javiana-induced cytotoxicity, while heat-killed LAB cultures had no effect on S. Javiana invasion or cytotoxicity. qRT-PCR analysis revealed that S. Javiana exposed to L. acidophilus and L. rhamnosus exhibited reduced virulence gene expression. Moreover, pre-treating host cells with LAB prior to S. Javiana infection reduced host cell production of inflammatory cytokines. Data suggest a potential protective effect of L. acidophilus, L. rhamnosus and L. casei against intestinal epithelial infection and pathogen-induced damage caused by S. Javiana.

Are Probiotics Effective in Targeting Alcoholic Liver Diseases?

Alcoholic liver disease (ALD) encompasses a broad spectrum of disorders including steatosis, steatohepatitis, fibrosis, and cirrhosis. Despite intensive research in the last two decades, there is currently no Food and Drug Administration-approved therapy for treating ALD. Several studies have demonstrated the importance of the gut-liver axis and gut microbiome on the pathogenesis of ALD. Alcohol may induce intestinal dysbiosis and increased intestinal permeability, which in turn result in increased levels of pathogen-associated molecular patterns such as lipopolysaccharide (LPS) and translocation of microbial products from the gut to the liver (bacterial translocation). LPS is an inflammatory signal that activates toll-like receptor 4 on Kupffer cells, contributing to the inflammation observed in ALD. Recently, probiotics have been shown to be effective in reducing or preventing the progression of ALD. A potential mechanism is that the probiotics transforms the composition of intestinal microbiota, which leads to reductions in alcohol-induced dysbiosis, intestinal permeability, bacterial translocation, endotoxemia, and consequently, the development of ALD. While transformation of intestinal microbiota by probiotics appears to be a promising therapeutic strategy for the treatment of intestinal barrier dysfunction, there is a scarcity of research that studies probiotics in the context of ALD. In this review, we discuss the potential therapeutic applications of probiotics in the treatment of ALD.

Early downregulation of P-glycoprotein facilitates bacterial attachment to intestinal epithelial cells and thereby triggers barrier dysfunction in a rodent model of total parenteral nutrition

Intestinal barrier dysfunction is a major complication of total parenteral nutrition (TPN). Our preliminary study revealed that intestinal P-glycoprotein (P-gp) was significantly downregulated under TPN treatment followed by disruption of barrier function, and thus the significance of early downregulation of P-gp needs to be addressed. Herein, we report a pivotal role of P-gp in the development of intestinal barrier dysfunction under TPN. Functional suppression of P-gp may facilitate bacterial attachment to intestinal epithelial cells (IECs) and thereby induce degradation of tight junctions to trigger barrier dysfunction. By using a rat model of TPN, we found early downregulation of P-gp function in ileum after 3-day TPN, followed by disruption of barrier function after 7-day TPN. By using Escherichia coli (E. coli) k88 and DH5α as type strains, we found significantly increased bacterial attachment to IECs in TPN group compared to sham. By using Caco-2 cells as an IEC model in vitro, we found that functional suppression of P-gp remarkably facilitated bacterial attachment to Caco-2 cells, leading to subsequent disruption of intestinal barrier function. Of note, Occludin was significantly downregulated by bacterial attachment when P-gp was functionally suppressed. Mechanistically, changes on Occludin were attributed to enhanced protein degradation instead of suppressed protein translation. Despite the half-life of Occludin protein being unchanged by DH5α treatment alone, it was decreased by about 40% when P-gp was simultaneously suppressed. Taken together, our findings revealed that early downregulation of intestinal P-gp under TPN may be a potential therapeutic target to prevent the development of barrier dysfunction.

Consortium of Probiotics Attenuates Colonization of Clostridioides difficile

Clostridioides difficile infection (CDI) is increasing morbidity and mortality rates globally. Fecal microbiota transplantation (FMT), an effective therapy for eliminating Clostridioides difficile (C. difficile), cannot be used extensive due to a range of challenges. Probiotics thus constitutes a promising alternative therapy. In our study, we evaluated the effect of consortium of probiotics including five Lactobacilli strains and two Bifidobacterium strains on the colonization of toxigenic BI/NAP1/027 C. difficile in a mouse model. The results of 16S rRNA sequencing and targeted metabolomics showed the consortium of probiotics effectively decreased the colonization of C. difficile, changed the α- and β-diversity of the gut microbiota, decreased the primary bile acids, and increased the secondary bile acids. Spearman’s correlation showed that some of the OTUs such as Akkermansia, Bacteroides, Blautia et al. were positively correlated with C. difficile numbers and the primary bile acids, and negatively correlated with the secondary bile acids. However, some of the OTUs, such as Butyricicoccus, Ruminococcus, and Rikenellaceae, were negatively correlated with C. difficile copies and the primary bile acids, and positively correlated with the secondary bile acids. In summary, the consortium of probiotics effectively decreases the colonization of C. difficile, probably via alteration of gut microbiota and bile acids. Our probiotics mixture thus offers a promising FMT alternative.

Lactobacillus rhamnosus GG and Saccharomyces cerevisiae boulardii exert synergistic antipathogenic activity in vitro against enterotoxigenic Escherichia coli

Short-term colonic in vitro batch incubations were performed to elucidate the possible synergistic effects of Lactobacillus rhamnosus GG (CNCM-I-4798) and Saccharomyces cerevisiae boulardii (CNCM-I-1079) (associated in Smebiocta/Smectaflora Protect®) on the colonic microbial fermentation process, as well as their antipathogenic activity against enterotoxigenic Escherichia coli (LMG2092) (ETEC). These incubations adequately simulate the native microbiota and environmental conditions of the proximal colon of both adult and toddler donors, including the colonic mucosal layer. Results indicated that both strains were capable of growing together without showing antagonistic effects. Co-cultivation of both strains resulted in increased butyrate (stimulated by L. rhamnosus GG), propionate (stimulated by S. boulardii), and ethanol (produced by S. boulardii) production compared to the control incubations, revealing the additive effect of both strains. After inoculation of ETEC under simulated dysbiotic conditions, a 40 and 46% reduction in the concentration of ETEC was observed upon addition of both strains during the experiments with the adult and toddler donor, respectively. Furthermore, ETEC toxin levels decreased upon S. boulardii inoculation, probably due to proteolytic activity of this strain, with a synergistic effect being observed upon co-cultivation of L. rhamnosus GG and S. boulardii resulting in a reduction of 57 and 46% for the adult and toddler donor, respectively. Altogether, the results suggest that both probiotics together may help microbiota functionality, in both adults and toddlers and under healthy or impaired conditions, which could be of great interest when the colonic microbiota is dysbiotic and therefore sensitive to pathogenic invasion such as during antibiotic treatment.

Lactobacillus rhamnosus Lcr35 as an effective treatment for preventing Candida albicans infection in the invertebrate model Caenorhabditis elegans: First mechanistic insights

The increased recurrence of Candida albicans infections is associated with greater resistance to antifungal drugs. This involves the establishment of alternative therapeutic protocols, such as probiotic microorganisms whose antifungal potential has already been demonstrated using preclinical models (cell cultures, laboratory animals). Understanding the mechanisms of action of probiotic microorganisms has become a strategic need for the development of new therapeutics for humans. In this study, we investigated the prophylactic anti-C. albicans properties of Lactobacillus rhamnosus Lcr35® using the in vitro Caco-2 cell model and the in vivo Caenorhabditis elegans model. In Caco-2 cells, we showed that the strain Lcr35® significantly inhibited the growth (~2 log CFU.mL-1) and adhesion (150 to 6,300 times less) of the pathogen. Moreover, in addition to having a pro-longevity activity in the nematode (+42.9%, p = 3.56.10-6), Lcr35® protects the animal from the fungal infection (+267% of survival, p < 2.10-16) even if the yeast is still detectable in its intestine. At the mechanistic level, we noticed the repression of genes of the p38 MAPK signalling pathway and genes involved in the antifungal response induced by Lcr35®, suggesting that the pathogen no longer appears to be detected by the worm immune system. However, the DAF-16/FOXO transcription factor, implicated in the longevity and antipathogenic response of C. elegans, is activated by Lcr35®. These results suggest that the probiotic strain acts by stimulating its host via DAF-16 but also by suppressing the virulence of the pathogen.

Bacteroides fragilis Strain ZY-312 Defense against Cronobacter sakazakii-Induced Necrotizing Enterocolitis In Vitro and in a Neonatal Rat Model

Cronobacter sakazakii is an important pathogen associated with the development of necrotizing enterocolitis (NEC), infant sepsis, and meningitis. Several randomized prospective clinical trials demonstrated that oral probiotics could decrease the incidence of NEC. Previously, we isolated and characterized a novel probiotic, Bacteroides fragilis strain ZY-312. However, it remains unclear how ZY-312 protects the host from the effects of C. sakazakii infection. To understand the underlying mechanisms triggering the probiotic effects, we tested the hypothesis that there was cross talk between probiotics/probiotics-modulated microbiota and the local immune system, governed by the permeability of the intestinal mucosa, using in vitro and in vivo models for the intestinal permeability. The probiotic effects of ZY-312 on intestinal epithelial cells were first examined, and the results revealed that ZY-312 inhibited C. sakazakii invasion, C. sakazakii-induced dual cell death (pyroptosis and apoptosis), and epithelial barrier dysfunction in vitro and in vivo The presence of ZY-312 also resulted in decreased expression of an inflammasome (NOD-like receptor family member pyrin domain-containing protein 3 [NLRP3]), caspase-3, and serine protease caspase-1 in a neonatal rat model. Furthermore, ZY-312 significantly modulated the compositions of the intestinal bacterial communities and decreased the relative abundances of Proteobacteria and Gammaproteobacteria but increased the relative abundances of Bacteroides and Bacillus in neonatal rats. In conclusion, our findings have shown for the first time that the probiotic B. fragilis ZY-312 suppresses C. sakazakii-induced NEC by modulating the proinflammatory response and dual cell death (apoptosis and pyroptosis).IMPORTANCE Cronobacter sakazakii is an opportunistic pathogenic bacterium that can cause necrotizing enterocolitis (NEC). However, the mechanism of pathogenicity of C. sakazakii is largely unknown. Here we have now demonstrated that apoptotic and pyroptotic stimuli are effectors of C. sakazakii-induced NEC. Previously, we isolated a novel probiotic strain candidate from fecal samples from healthy infants and characterized it as Bacteroides fragilis strain ZY-312. Functional characterization reveals that ZY-312 inhibited C. sakazakii invasion, restoring epithelial barrier dysfunction, decreasing the expression of inflammatory cytokines, and reducing dual cell death (pyroptosis and apoptosis). Furthermore, the presence of ZY-132 was sufficient to hinder the adverse reaction seen with C. sakazakii in a C. sakazakii-induced NEC model. Taking the results together, our study demonstrated the utility of ZY-312 as a promising probiotic agent for the prevention of NEC.

Lactobacillus plantarum TW1-1 Alleviates Diethylhexylphthalate-Induced Testicular Damage in Mice by Modulating Gut Microbiota and Decreasing Inflammation

Diethylhexylphthalate (DEHP), acting as an endocrine disruptor, disturbed reproductive health. Here, we evaluated the effects of Lactobacillus plantarum TW1-1 (L. plantarum TW1-1) on DEHP-induced testicular damage in adult male mice. Results showed that oral supplementation of L. plantarum TW1-1 significantly increased the serum testosterone concentration, enhanced the semen quality, and attenuated gonad development defects in DEHP-exposed mice. L. plantarum TW1-1 also alleviated DEHP-induced oxidative stress and inflammatory responses by decreasing the mRNA expression and serum protein concentration of different inflammatory factors [tumor necrosis factor-α, interleukin (IL)-1β and IL-6]. Furthermore, L. plantarum TW1-1 significantly reduced DEHP-induced intestinal hyper-permeability and the increase in the serum lipopolysaccharide level. Gut microbiota diversity analysis revealed that L. plantarum TW1-1 shifted the DEHP-disrupted gut microbiota to that of the control mice. At phylum level, L. plantarum TW1-1 reversed DEHP-induced Bacteroidetes increase and Firmicutes decrease, and restored Deferribacteres in DEHP-exposed mice. Spearman's correlation analysis showed that Bacteroidetes, Deferribacteres, and Firmicutes were associated with DEHP-induced testicular damage. In addition, the ratio of Firmicutes to Bacteroidetes (Firm/Bac ratio) significantly decreased from 0.28 (control group) to 0.13 (DEHP-exposed group), which was restored by L. plantarum TW1-1 treatment. Correlation analysis showed that the Firm/Bac ratio was negatively correlated with testicular damage and inflammation. These findings suggest that L. plantarum TW1-1 prevents DEHP-induced testicular damage via modulating gut microbiota and decreasing inflammation.

The Influence of Heat-Killed Enterococcus faecium BGPAS1-3 on the Tight Junction Protein Expression and Immune Function in Differentiated Caco-2 Cells Infected With Listeria monocytogenes ATCC 19111

Listeria monocytogenes, the common foodborne pathogenic bacteria species, compromises the intestinal epithelial barrier, leading to development of the listeriosis, a severe disease especially among immunocompromised individuals. L. monocytogenes infection usually requires antibiotic treatment, however, excessive use of antibiotics promotes emergence of antibiotic resistance and the destruction of gut microbiota. Probiotics, including lactic acid bacteria (LAB), have been repeatedly proven as an alternative approach for the treatment of various infections. We have analyzed the potential of Enterococcus faecium BGPAS1-3, a dairy isolate exhibiting strong direct antilisterial effect, to modulate the response of differentiated Caco-2 intestinal epithelial cells to L. monocytogenes ATCC 19111 infection. We showed that the molecule with antilisterial effect is a bacterial cell-wall protein that is highly resistant to the high-temperature treatment. When we tested the antilisterial potential of heat-killed BGPAS1-3, we found that it could prevent tight junction disruption in differentiated Caco-2 monolayer infected with L. monocytogenes ATCC 19111, induce antilisterial host response mechanisms, and stimulate the production of protective TGF-β in intestinal epithelial cells. We also showed that the modulation of MyD88 dependent TLR2 and TLR4 pathways by BGPAS1-3 are involved in host response against L. monocytogenes ATCC 19111. Since heat-killed BGPAS1-3 possess strong antilisterial effects, such postbiotic could be used as a controllable and safe therapeutic.

The Foodborne Strain Lactobacillus fermentum MBC2 Triggers pept-1-Dependent Pro-Longevity Effects in Caenorhabditis elegans

Lactic acid bacteria (LAB) are involved in several food fermentations and many of them provide strain-specific health benefits. Herein, the probiotic potential of the foodborne strain Lactobacillus fermentum MBC2 was investigated through in vitro and in vivo approaches. Caenorhabditis elegans was used as an in vivo model to analyze pro-longevity and anti-aging effects. L. fermentum MBC2 showed a high gut colonization capability compared to E. coli OP50 (OP50) or L.rhamnosus GG (LGG). Moreover, analysis of pumping rate, lipofuscin accumulation, and body bending showed anti-aging effects in L. fermentum MBC2-fed worms. Studies on PEPT-1 mutants demonstrated that pept-1 gene was involved in the anti-aging processes mediated by this bacterial strain through DAF-16, whereas the oxidative stress protection was PEPT-1 independent. Moreover, analysis of acid tolerance, bile tolerance, and antibiotic susceptibility were evaluated. L. fermentum MBC2 exerted beneficial effects on nematode lifespan, influencing energy metabolism and oxidative stress resistance, resulted in being tolerant to acidic pH and able to adhere to Caco-2 cells. Overall, these findings provide new insight for application of this strain in the food industry as a newly isolated functional starter. Furthermore, these results will also shed light on C. elegans molecular players involved in host-microbe interactions.

Roles of Probiotic Lactobacilli Inclusion in Helping Piglets Establish Healthy Intestinal Inter-environment for Pathogen Defense

The gastrointestinal tract of pigs is densely populated with microorganisms that closely interact with the host and with ingested feed. Gut microbiota benefits the host by providing nutrients from dietary substrates and modulating the development and function of the digestive and immune systems. An optimized gastrointestinal microbiome is crucial for pigs' health, and establishment of the microbiome in piglets is especially important for growth and disease resistance. However, the microbiome in the gastrointestinal tract of piglets is immature and easily influenced by the environment. Supplementing the microbiome of piglets with probiotic bacteria such as Lactobacillus could help create an optimized microbiome by improving the abundance and number of lactobacilli and other indigenous probiotic bacteria. Dominant indigenous probiotic bacteria could improve piglets' growth and immunity through certain cascade signal transduction pathways. The piglet body provides a permissive habitat and nutrients for bacterial colonization and growth. In return, probiotic bacteria produce prebiotics such as short-chain fatty acids and bacteriocins that benefit piglets by enhancing their growth and reducing their risk of enteric infection by pathogens. A comprehensive understanding of the interactions between piglets and members of their gut microbiota will help develop new dietary interventions that can enhance piglets' growth, protect piglets from enteric diseases caused by pathogenic bacteria, and maximize host feed utilization.

Deoxynivalenol decreased intestinal immune function related to NF-κB and TOR signalling in juvenile grass carp (Ctenopharyngodon idella)

Deoxynivalenol (DON) is one of the most common mycotoxins in animal feed worldwide and causes significant threats to the animal production. The intestine is an important mucosal immune organ in teleost, and it is also the first target for feed-borne toxicants in animal. However, studies concerning the effect of DON on fish intestine are scarce. This study explored the effects of DON on intestinal immune function in juvenile grass carp (Ctenopharyngodon idella). A total of 1440 juvenile grass carp (12.17 ± 0.01 g) were fed six diets containing graded levels of DON (27, 318, 636, 922, 1243 and 1515 μg/kg diet) for 60 days. After the growth trial, fish were challenged with Aeromonas hydrophila. The results were analysed by the Duncan's multiple-range test (P < 0.05), indicating that compared with the control group (27 μg/kg diet), dietary DON levels up to 318 μg/kg diet: (1) decreased lysozyme (LZ) and acid phosphatase (ACP) activities, as well as complement 3 (C3), C4 and immunoglobulin M (IgM) content in the proximal intestine (PI), middle intestine (MI) and distal intestine (DI) of juvenile grass carp (P < 0.05); (2) down-regulated the mRNA levels of anti-microbial substance: liver expressed antimicrobial peptide (LEAP) -2A, LEAP-2B, hepcidin, β-defensin-1 and mucin2 in the PI, MI and DI of juvenile grass carp (P < 0.05); (3) up-regulated the mRNA levels of pro-inflammatory cytokines [interleukin 1β (IL-1β), tumour necrosis factor α (TNF-α), interferon γ2 (INF-γ2), IL-6 (only in PI), IL-8, IL-12p35, IL-12p40, IL-15 and IL-17D] in the PI, MI and DI of juvenile grass carp (P < 0.05), which might be partly related to nuclear factor kappa B (NF-κB) signalling [IκB kinase β (IKKβ) and IKKγ/inhibitor of κBα (IκBα)/NF-κB (p65 and c-Rel)]; and (4) down-regulated the mRNA levels of anti-inflammatory cytokines [IL-10, IL-11, IL-4/13A (not IL-4/13B), transforming growth factor β1 (TGF-β1) (not TGF-β2)] in the PI, MI and DI of juvenile grass carp (P < 0.05), which might be partly related to target of rapamycin (TOR) signalling [TOR/ribosomal protein S6 kinases 1 (S6K1) and eIF4E-binding proteins (4E-BP)]. All data indicated that DON could impair the intestinal immune function, and its potential regulation mechanisms were partly associated with NF-κB and TOR signalling pathways. Finally, based on the enteritis morbidity, and the LZ and ACP activities as well as IgM content in the PI, the reasonable dose of DON for grass carp were estimated to be 251.66, 305.83, 252.34 and 309.94 μg/kg diet, respectively.

Lactobacillus plantarum TW1-1 Alleviates Diethylhexylphthalate-Induced Testicular Damage in Mice by Modulating Gut Microbiota and Decreasing Inflammation

Diethylhexylphthalate (DEHP), acting as an endocrine disruptor, disturbed reproductive health. Here, we evaluated the effects of Lactobacillus plantarum TW1-1 (L. plantarum TW1-1) on DEHP-induced testicular damage in adult male mice. Results showed that oral supplementation of L. plantarum TW1-1 significantly increased the serum testosterone concentration, enhanced the semen quality, and attenuated gonad development defects in DEHP-exposed mice. L. plantarum TW1-1 also alleviated DEHP-induced oxidative stress and inflammatory responses by decreasing the mRNA expression and serum protein concentration of different inflammatory factors [tumor necrosis factor-α, interleukin (IL)-1β and IL-6]. Furthermore, L. plantarum TW1-1 significantly reduced DEHP-induced intestinal hyper-permeability and the increase in the serum lipopolysaccharide level. Gut microbiota diversity analysis revealed that L. plantarum TW1-1 shifted the DEHP-disrupted gut microbiota to that of the control mice. At phylum level, L. plantarum TW1-1 reversed DEHP-induced Bacteroidetes increase and Firmicutes decrease, and restored Deferribacteres in DEHP-exposed mice. Spearman's correlation analysis showed that Bacteroidetes, Deferribacteres, and Firmicutes were associated with DEHP-induced testicular damage. In addition, the ratio of Firmicutes to Bacteroidetes (Firm/Bac ratio) significantly decreased from 0.28 (control group) to 0.13 (DEHP-exposed group), which was restored by L. plantarum TW1-1 treatment. Correlation analysis showed that the Firm/Bac ratio was negatively correlated with testicular damage and inflammation. These findings suggest that L. plantarum TW1-1 prevents DEHP-induced testicular damage via modulating gut microbiota and decreasing inflammation.

A novel probiotic, Lactobacillus johnsonii 456, resists acid and can persist in the human gut beyond the initial ingestion period

Probiotics are considered to have multiple beneficial effects on the human gastrointestinal tract, including immunomodulation, pathogen inhibition, and improved host nutrient metabolism. However, extensive characterization of these properties is needed to define suitable clinical applications for probiotic candidates. Lactobacillus johnsonii 456 (LBJ 456) was previously demonstrated to have anti-inflammatory and anti-genotoxic effects in a mouse model. Here, we characterize its resistance to gastric and bile acids as well as its ability to inhibit gut pathogens and adhere to host mucosa. While bile resistance and in vitro host attachment properties of LBJ 456 were comparable to other tested probiotics, LBJ 456 maintained higher viability at lower pH conditions compared to other tested strains. LBJ 456 also altered pathogen adhesion to LS 174T monolayers and demonstrated contact-dependent and independent inhibition of pathogen growth. Genome analyses further revealed possible genetic elements involved in host attachment and pathogen inhibition. Importantly, we show that ingestion of Lactobacillus johnsonii 456 over a one week yogurt course leads to persistent viable bacteria detectable even beyond the period of initial ingestion, unlike many other previously described probiotic species of lactic acid bacteria.

Cell Signaling of Caenorhabditis elegans in Response to Enterotoxigenic Escherichia coli Infection and Lactobacillus zeae Protection

Enterotoxigenic Escherichia coli (ETEC) infection causes the death of Caenorhabditis elegans, which can be prevented by certain Lactobacillus isolates. The host response of C. elegans to ETEC infection and its regulation by the isolates are, however, largely unclear. This study has revealed that, in agreement with the results of life-span assays, the expression of the genes encoding p38 mitogen-activated protein kinase (MAPK) pathway (nsy-1, sek-1, and pmk-1), insulin/insulin-like growth factor (DAF/IGF) pathway (daf-16), or antimicrobial peptides (lys-7, spp-1, and abf-3) and other defensing molecules (abf-2, clec-85) was upregulated significantly when the wild-type nematode (N2) was subjected to ETEC infection. This upregulation was further enhanced by the pretreatment with Lactobacillus zeae LB1, but not with L. casei CL11. Mutants defective in the cell signaling of C. elegans were either more susceptible (defective in NSY-1, SEK-1, PMK-1, or DAF16) or more resistant (defective in AGE-1, DBL-1, SKN-1, or SOD-3) to ETEC infection compared with the wild-type. Mutants defective in antimicrobial peptides (LYS-7, SPP1, or ABF-3) were also more susceptible. In addition, mutants that are defective in NSY-1, SEK-1, PMK-1, DAF16, ABF-3, LYS-7, or SPP1 showed no response to the protection from L. zeae LB1. The expression of the genes encoding antimicrobial peptides (lys-7, spp-1, and abf-3) and other defensing molecules (abf-2, clec-60, and clec-85) were almost all upregulated in AGE-1- or DBL-1-defective mutant compared with the wild-type, which was further enhanced by the pretreatment of L. zeae LB1. The expression of these genes was, however, mostly downregulated in NSY-1- or DAF-16-defective mutant. These results suggest that L. zeae LB1 regulates C. elegans signaling through the p38 MAPK and DAF/IGF pathways to control the production of antimicrobial peptides and defensing molecules to combat ETEC infection.

Characterization and anti-salmonella activities of lactic acid bacteria isolated from cattle faeces

Background

Non typhoidal salmonellosis is one of the neglected zoonoses in most African countries. The use of sub-therapeutic doses of antibiotics as animal growth promoter enhances the emergence and dissemination of antimicrobial resistance in bacteria with food animal reservoirs and may also results in antibiotics residue in animal products. One promising alternative to antibiotics in animal feed is Lactic Acid Bacteria (LAB) as probiotics. This study was carried out to determine the anti-salmonella activities and suitability of LAB isolated from cattle faeces in Nigeria as potential probiotics in cattle feed.

Method

The test Salmonella enterica spp strains and LAB were isolated from cattle faeces and identified by MALDI-TOF MS and partial sequencing of 16S rRNA genes respectively. The anti-salmonella activities of the isolated LAB in co-culture, cell-free supernatant, inhibition of growth by viable LAB cells and quantification of organic acids were determined by standard techniques. The ability of the LAB strains to withstand gastric conditions, antibiotic susceptibility and their haemolytic ability on blood agar were also determined.

Results

A total of 88 LAB belonging to 15 species were isolated and identified from cattle faeces. The most abundant species were Streptococcus infantarius (26), Enterococcus hirae (12), Lactobacillus amylovorus (10), Lactobacillus mucosae (10) and Lactobacillus ingluviei (9). Most of the LAB strains showed good anti-salmonella activities against the test Salmonella enterica spp. with 2 Lactobacillus strains; Lactobacillus amylovorus C94 and Lactobacillus salivarius C86 exhibiting remarkable anti-salmonella activities with total inhibition of Salmonella spp after 18 hours of co-incubation. The selected strains were able to survive simultaneous growth at pH 3 and 7% bile concentration and are non hemolytic.

Conclusion

This study reports the vast diversity of culturable LAB in cattle faeces from Nigeria and their putative in-vitro antibacterial activity against Salmonella enterica spp isolated from cattle. Lactobacillus amylovorus C94 and Lactobacillus salivarius C86 demonstrated promising probiotic potentials in-vitro and will be further tested in-vivo in animal field trial.

Bifidobacterium animalis subspecies lactis modulates the local immune response and glucose uptake in the small intestine of juvenile pigs infected with the parasitic nematode Ascaris suum

An evaluation of a localized intestinal allergic type-2 response concomitant with consumption of probiotic bacteria is not well documented. This study investigated the effect of feeding probiotic Bifidobacterium animalis subspecies lactis (Bb12) or a placebo in weaned pigs that were also inoculated with Ascaris suum (A. suum) eggs to induce a strong Th2-dependent allergic type 2 immune response. Sections of jejunal mucosa were mounted in Ussing chambers to determine changes in permeability and glucose absorption, intestine and liver samples were collected for analysis of type-2 related gene expression, jejunum examined histologically, and sera and intestinal fluid were assayed for parasite antigen specific antibody. The prototypical parasite-induced secretory response to histamine and reduced absorption of glucose in the jejunum were attenuated by feeding Bb12 without a change in mucosal resistance. Parasite antigen-specific IgA response in the serum and IgG1 and IgG2 response in the ileal fluid were significantly increased in A. suum-infected pigs treated with Bb12 compared to infected pigs given the placebo. Ascaris suum-induced eosinophilia in the small intestinal mucosa was inhibited by Bb12 treatment without affecting the normal expulsion of A. suum 4th stage larvae (L4) or the morphometry of the intestine. Expression of genes associated with Th1/Th2 cells, Treg cells, mast cells, and physiological function in the intestine were modulated in A. suum infected-pigs treated with Bb12. These results suggested that Bb12 can alter local immune responses and improve intestinal function during a nematode infection by reducing components of a strong allergenic type-2 response in the pig without compromising normal parasite expulsion.

Protective Effects of Lactic Acid Bacteria Against TLR4 Induced Inflammatory Response in Hepatoma HepG2 Cells Through Modulation of Toll-Like Receptor Negative Regulators of Mitogen-Activated Protein Kinase and NF-κB Signaling

The beneficial effects of probiotics in several liver diseases have been investigated in both animal and clinical models; however, the precise mechanisms responsible for their effects have not yet been elucidated. Gut transmitted endotoxins such as LPS have been shown to play critical roles in hepatic inflammation and injury. Therefore, in this study, we investigated the beneficial role of selected lactic acid bacteria (LABs) on reduction of hepatic steatosis (HS) and attenuation of LPS induced inflammatory response in vitro. Total cellular fluid (TCF) of LABs treatment reduced HS by decreasing the amount of lipid accumulation in vitro. Additionally, HepG2 cells exposed to LPS showed increased expression of exacerbated inflammatory cytokines, such as IL-6, CXCL8, CCL2, and TNF-α, but these effects were counteracted when cells were treated with TCF of LABs prior to LPS challenge. Moreover, TCF of LABs was able to modulate mRNA levels of TLR negative regulators and protein levels of p38 MAPK and p65 NF-κB transcription factors. However, these modulations were differed remarkably between both free fatty acid treated and untreated HepG2 cells. Heat-killed LABs were also indirectly suppressed THP-1 cells to produce higher level of IL-10, TLR4, and lower at genes level of TGF-β, IL-1β, and IL-6, and at protein level of TNF-α in response to LPS. Taken together, our findings indicate that selected LABs exhibit profound immunoregulatory effects on liver cells via modulation of TLR negative regulators of the MAPK and NF-κB pathways.

Swine-Derived Probiotic Lactobacillus plantarum Inhibits Growth and Adhesion of Enterotoxigenic Escherichia coli and Mediates Host Defense

Weaning stress renders piglets susceptible to pathogen infection, which leads to post-weaning diarrhea, a severe condition characterized by heavy diarrhea and mortality in piglets. Enterotoxigenic Escherichia coli (ETEC) is one of typical strains associated with post-weaning diarrhea. Thus, prevention and inhibition of ETEC infection are of great concern. Probiotics possess anti-pathogenic activity and can counteract ETEC infection; however, their underlying mechanisms and modes of action have not yet been clarified. In the present study, the direct and indirect protective effects of Lactobacillus plantarum ZLP001 against ETEC infection were investigated by different methods. We found that bacterial culture and culture supernatant of L. plantarum ZLP001 prevented ETEC growth by the Oxford cup method, and ETEC growth inhibition was observed in a co-culture assay as well. This effect was suggested to be caused mainly by antimicrobial metabolites produced by L. plantarum ZLP001. In addition, adhesion capacity of L. plantarum ZLP001 to IPEC-J2 cells were observed using microscopy and counting. L. plantarum ZLP001 also exhibited a concentration-dependent ability to inhibit ETEC adhesion to IPEC-J2 cells, which mainly occurred via exclusion and competition mode. Furthermore, quantitative real time polymerase chain reaction (qPCR) analysis showed that L. plantarum ZLP001 upregulated the expression of host defense peptides (HDPs) but did not trigger an inflammatory response. In addition, L. plantarum ZLP001 induced HDP secretion, which enhanced the potential antimicrobial activity of IPEC-J2 cell-culture supernatant after incubation with L. plantarum ZLP001. Our findings demonstrate that L. plantarum ZLP001, an intestinal Lactobacillus species associated with piglet health, possesses anti-ETEC activity. L. plantarum ZLP001 might prevent ETEC growth, inhibit ETEC adhesion to the intestinal mucosa, and activate the innate immune response to secret antimicrobial peptides. L. plantarum ZLP001 is worth investigation as a potential probiotics.

The anti-apoptotic and anti-inflammatory effect of Lactobacillus acidophilus on Shigella sonnei and Vibrio cholerae interaction with intestinal epithelial cells: A comparison between invasive and non-invasive bacteria

The aim of this study was to compare the effect of Lactobacillus acidophilus on the attachment, invasion, and interaction of Shigella sonnei and Vibrio cholerae with Caco-2 epithelial cells. Also, the anti-apoptotic and anti-inflammatory effect of L. acidophilus was investigated on S. sonnei and V. cholerae interaction with Caco-2 cells as the representatives of invasive and non-invasive intestinal bacteria. It was found that pretreatment with L. acidophilus significantly prevented from adherence and internalization of S. sonnei/V. cholerae and reduced the expression of tumour necrosis factor-α and interleukin-8 in host cells. No significant difference was observed in inhibitory effect of Lactobacilli in V. cholerae and S. sonnei attachment, emphasizing on the role of lactobacilli as a physical barrier in inhibiting direct contact with host cell by competitive exclusion, which may affect attachment and subsequent internalization of both invasive and non-invasive pathogenic bacteria in a same scale. The evaluation of early and late apoptosis in Caco-2 cells exposed to V. cholerae/S. sonnei and pretreated by L. acidophilus indicated no remarkable difference in L. acidophilus anti-apoptotic effect on Caco-2 cells against invasive and non-invasive bacterial infection. Moreover, L. acidophilus by itself showed no apoptotic effect on Caco-2 cells. Statistical analysis revealed that L. acidophilus in S. sonnei infected cells was able to reduce pro-inflammatory immune responses (TNF-α, IL-8 and IL-1β) and NO and PGE₂ secretion more strongly compared with V. cholerae infected cells. These data showed for the first time that the protective effect of Lactobacilli, as a probiotic bacterium, in interaction suppression was more in invasive bacteria including S. sonnei than in non-invasive V. cholerae.

Effects of Lactobacillus rhamnosus GG and Escherichia coli Nissle 1917 Cell-Free Supernatants on Modulation of Mucin and Cytokine Secretion on Human Intestinal Epithelial HT29-MTX Cells

This study examined modulation effects of cell-free supernatants of two commonly studied probiotic bacteria Lactobacillus rhamnosus GG (LGG) and Escherichia coli Nissle 1917 (EcN) on mucin and cytokine profiles of human intestinal epithelial HT29-MTX cells. It was found that LGG and EcN supernatants differentially modulated MUC5AC and MUC5B mRNA and protein, and total mucin-like glycoprotein secretion. Regarding modulation of cytokine profiles, LGG supernatants moderately influenced the secretion of anti-inflammatory cytokines such as interleukin (IL)-4, IL-5, and IL-10, while those of EcN exerted a broad proinflammatory effect to intestinal epithelial cells by inducing the secretion of proinflammatory cytokines such as IL-8, monocyte chemotactic protein-1, transforming growth factor α, tumor necrosis factor α, granulocyte macrophage colony-stimulating factor, and interferon γ. These results suggested that LGG and EcN might produce different bioactive products that display differential modulation of mucin and cytokines, which may contribute to intestinal health and/or defense against bacteria/pathogens.

PRACTICAL APPLICATION

The results suggested that LGG and EcN might produce different bioactive products that display differential modulation of mucin and cytokines, which may contribute to intestinal health and/or defense against bacteria/pathogens.

Connecting the immune system, systemic chronic inflammation and the gut microbiome: The role of sex

Unresolved low grade systemic inflammation represents the underlying pathological mechanism driving immune and metabolic pathways involved in autoimmune diseases (AID). Mechanistic studies in animal models of AID and observational studies in patients have found alterations in gut microbiota communities and their metabolites, suggesting a microbial contribution to the onset or progression of AID. The gut microbiota and its metabolites have been shown to influence immune functions and immune homeostasis both within the gut and systematically. Microbial derived-short chain fatty acid (SCFA) and bio-transformed bile acid (BA) have been shown to influence the immune system acting as ligands specific cell signaling receptors like GPRCs, TGR5 and FXR, or via epigenetic processes. Similarly, intestinal permeability (leaky gut) and bacterial translocation are important contributors to chronic systemic inflammation and, without repair of the intestinal barrier, might represent a continuous inflammatory stimulus capable of triggering autoimmune processes. Recent studies indicate gender-specific differences in immunity, with the gut microbiota shaping and being concomitantly shaped by the hormonal milieu governing differences between the sexes. A bi-directional cross-talk between microbiota and the endocrine system is emerging with bacteria being able to produce hormones (e.g. serotonin, dopamine and somatostatine), respond to host hormones (e.g. estrogens) and regulate host hormones' homeostasis (e.g by inhibiting gene prolactin transcription or converting glucocorticoids to androgens). We review herein how gut microbiota and its metabolites regulate immune function, intestinal permeability and possibly AID pathological processes. Further, we describe the dysbiosis within the gut microbiota observed in different AID and speculate how restoring gut microbiota composition and its regulatory metabolites by dietary intervention including prebiotics and probiotics could help in preventing or ameliorating AID. Finally, we suggest that, given consistent observations of microbiota dysbiosis associated with AID and the ability of SCFA and BA to regulate intestinal permeability and inflammation, further mechanistic studies, examining how dietary microbiota modulation can protect against AID, hold considerable potential to tackle increased incidence of AID at the population level.

In vitro adhesion and anti-inflammatory properties of native Lactobacillus fermentum and Lactobacillus delbrueckii spp

AIMS

This study aimed at characterizing the adhesion and immune-stimulatory properties of native probiotic Lactobacillus fermentum (MCC 2759 and MCC 2760) and Lactobacillus delbrueckii MCC 2775.

METHODS AND RESULTS

Adhesion of the strains was assessed in Caco-2 and HT-29 cell lines. Expression of adhesion and immune markers were evaluated in Caco-2 cells by real-time qPCR. The cultures displayed >80% of adhesion to both cell lines and also induced the expression of mucin-binding protein (mub) gene in the presence of mucin, bile and pancreatin. Adhesion was mediated by carbohydrate and proteinaceous factors. The cultures stimulated the expression of inflammatory cytokines in Caco-2 cells. However, pro-inflammatory genes were down-regulated upon challenge with lipopolysaccharide and IL-10 was up-regulated by the cultures. Cell wall extract of L. fermentum MCC 2760 induced the expression of IL-6 by 5·47-fold, whereas crude culture filtrate enhanced the expression of IL-10 by 14·87-fold compared to LPS control.

CONCLUSIONS

The bacterial cultures exhibited strong adhesion and anti-inflammatory properties.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first report to reveal the role of adhesion markers of L. fermentum and L. delbrueckii by qPCR. The strain-specific anti-inflammatory property of native cultures may be useful to alleviate inflammatory conditions and develop a target-based probiotic.

In Vitro and in Vivo Selection of Potentially Probiotic Lactobacilli From Nocellara del Belice Table Olives

Table olives are increasingly recognized as a vehicle as well as a source of probiotic bacteria, especially those fermented with traditional procedures based on the activity of indigenous microbial consortia, originating from local environments. In the present study, we report characterization at the species level of 49 Lactic Acid Bacteria (LAB) strains deriving from Nocellara del Belice table olives fermented with the Spanish or Castelvetrano methods, recently isolated in our previous work. Ribosomal 16S DNA analysis allowed identification of 4 Enterococcus gallinarum, 3 E. casseliflavus, 14 Leuconostoc mesenteroides, 19 Lactobacillus pentosus, 7 L. coryniformis, and 2 L. oligofermentans. The L. pentosus and L. coryniformis strains were subjected to further screening to evaluate their probiotic potential, using a combination of in vitro and in vivo approaches. The majority of them showed high survival rates under in vitro simulated gastro-intestinal conditions, and positive antimicrobial activity against Salmonella enterica serovar Typhimurium, Listeria monocytogenes and enterotoxigenic Escherichia coli (ETEC) pathogens. Evaluation of antibiotic resistance to ampicillin, tetracycline, chloramphenicol, or erythromycin was also performed for all selected strains. Three L. coryniformis strains were selected as very good performers in the initial in vitro testing screens, they were antibiotic susceptible, as well as capable of inhibiting pathogen growth in vitro. Parallel screening employing the simplified model organism Caenorhabditis elegans, fed the Lactobacillus strains as a food source, revealed that one L. pentosus and one L. coryniformis strains significantly induced prolongevity effects and protection from pathogen-mediated infection. Moreover, both strains displayed adhesion to human intestinal epithelial Caco-2 cells and were able to outcompete foodborne pathogens for cell adhesion. Overall, these results are suggestive of beneficial features for novel LAB strains, which renders them promising candidates as starters for the manufacturing of fermented table olives with probiotic added value.