Lactobacillus paracasei CBA L74 metabolic products and fermented milk for infant formula have anti-inflammatory activity on dendritic cells in vitro and protective effects against colitis and an enteric pathogen in vivo

Pre- to Postbiotics: The Beneficial Roles of Pediatric Dysbiosis Associated with Inflammatory Bowel Diseases

Probiotics are "live microorganisms which, when administered in adequate amount, confer health benefits on the host". They can be found in certain foods like yogurt and kefir and in dietary supplements. The introduction of bacterial derivatives has not only contributed to disease control but has also exhibited promising outcomes, such as improved survival rates, immune enhancement, and growth promotion effects. It is interesting to note that the efficacy of probiotics goes beyond the viability of the bacteria, giving rise to concepts like paraprobiotics, non-viable forms of probiotics, and postbiotics. Paraprobiotics offer various health benefits in children with intestinal dysbiosis, contributing to improved digestive health, immune function, and overall well-being. In this review, the potential of these therapeutic applications as alternatives to pharmacological agents for treating pediatric intestinal dysbiosis will be thoroughly evaluated. This includes an analysis of their efficacy, safety, long-term benefits, and their ability to restore gut microbiota balance, improve digestive health, enhance immune function, and reduce inflammation. The aim is to determine if these non-pharmacological interventions can effectively and safely manage intestinal dysbiosis in children, reducing the need for conventional medications and their side effects.

The Plethora of Microbes with Anti-Inflammatory Activities

Inflammation, which has important functions in human defense systems and in maintaining the dynamic homeostasis of the body, has become a major risk factor for the progression of many chronic diseases. Although the applied medical products alleviate the general status, they still exert adverse effects in the long term. For this reason, the solution should be sought in more harmless and affordable agents. Microorganisms offer a wide range of active substances with anti-inflammatory properties. They confer important advantages such as their renewable and inexhaustible nature. This review aims to provide the most recent updates on microorganisms of different types and genera, being carriers of anti-inflammatory activity.

Can Postbiotics Represent a New Strategy for NEC?

Intestinal bacteria, also known as gut microbiota, are a rich ecology of microorganisms found in the human digestive tract. Extensive study has highlighted their critical relevance in preserving human health. New research has revealed that bacterial viability is not invariably necessary to induce health benefits. Postbiotics (defined soluble substances produced as a byproduct of the metabolic processes of living microbes) have thus emerged as an important topic of research. They contribute to shaping the gut microbiota, exert immune-modulation activity, and improve the integrity of the gut barrier.Alterations in preterm gut colonization associated with intestinal barrier immaturity and the increased reactivity of the intestinal mucosa to colonizing bacteria have been implicated in the pathogenesis of necrotizing enterocolitis. Postbiotics have shown promising outcomes in reducing the risk of developing NEC, lowering inflammation, encouraging the development of good bacteria, and strengthening the intestinal barrier. This is an important advancement in newborn care and highlights the potential of postbiotics to avoid severe intestinal disorders.

Postbiotics: Functional Food Materials and Therapeutic Agents for Cancer, Diabetes, and Inflammatory Diseases

Postbiotics are (i) "soluble factors secreted by live bacteria, or released after bacterial lysis, such as enzymes, peptides, teichoic acids, peptidoglycan-derived muropeptides, polysaccharides, cell-surface proteins and organic acids"; (ii) "non-viable metabolites produced by microorganisms that exert biological effects on the hosts"; and (iii) "compounds produced by microorganisms, released from food components or microbial constituents, including non-viable cells that, when administered in adequate amounts, promote health and wellbeing". A probiotic- and prebiotic-rich diet ensures an adequate supply of these vital nutrients. During the anaerobic fermentation of organic nutrients, such as prebiotics, postbiotics act as a benevolent bioactive molecule matrix. Postbiotics can be used as functional components in the food industry by offering a number of advantages, such as being added to foods that are harmful to probiotic survival. Postbiotic supplements have grown in popularity in the food, cosmetic, and healthcare industries because of their numerous health advantages. Their classification depends on various factors, including the type of microorganism, structural composition, and physiological functions. This review offers a succinct introduction to postbiotics while discussing their salient features and classification, production, purification, characterization, biological functions, and applications in the food industry. Furthermore, their therapeutic mechanisms as antibacterial, antiviral, antioxidant, anticancer, anti-diabetic, and anti-inflammatory agents are elucidated.

Lactobacillus casei-Derived Postbiotics Elevate the Bioaccessibility of Proteins via Allosteric Regulation of Pepsin and Trypsin and Introduction of Endopeptidases

The potential of probiotics to benefit digestion has been widely reported, while its utilization in high-risk patients and potential adverse reactions have focused interest on postbiotics. A variable data-independent acquisition (vDIA)-based spatial-omics strategy integrated with unsupervised variational autoencoders was applied to profile the functional mechanism underlying the action of Lactobacillus casei-derived postbiotic supplementation in goat milk digestion in an infant digestive system, from a metabolomics-peptidomics-proteomics perspective. Amide and olefin derivatives were proved to elevate the activities of pepsin and trypsin through hydrogen bonding and hydrophobic forces based on allosteric effects, and recognition of nine endopeptidases and their cleavage to serine, proline, and aspartate were introduced by postbiotics, thereby promoting the generation of hydrophilic peptides and elevating the bioaccessibility of goat milk protein. The peptides originating from αs1-casein, β-casein, β-lactoglobulin, Ig-like domain-containing protein, κ-casein, and serum amyloid A protein, with multiple bioactivities including angiotensin I-converting enzyme (ACE)-inhibitory, osteoanabolic, dipeptidyl peptidase IV (DPP-IV) inhibitory, antimicrobial, bradykinin-potentiating, antioxidant, and anti-inflammatory activities, were significantly increased in the postbiotic supplementation group, which was also considered to potentially prevent necrotizing enterocolitis through inhibiting the multiplication of pathogenic bacteria and blocking signal transducer and activator of transcription 1 and nuclear factor kappa-light-chain-enhancer of activated B cells inflammatory pathways. This research deepened the understanding of the mechanism underlying the postbiotics affecting goat milk digestion, which established a critical groundwork for the clinical application of postbiotics in infant complementary foods.

Lactobacillus paracasei CNCM I-5220-derived postbiotic protects from the leaky-gut

The maintenance of intestinal barrier function is essential for preventing different pathologies, such as the leaky gut syndrome (LGS), which is characterized by the passage of harmful agents, like bacteria, toxins, and viruses, into the bloodstream. Intestinal barrier integrity is controlled by several players, including the gut microbiota. Various molecules, called postbiotics, are released during the natural metabolic activity of the microbiota. Postbiotics can regulate host–microbe interactions, epithelial homeostasis, and have overall benefits for our health. In this work, we used in vitro and in vivo systems to demonstrate the role of Lactobacillus paracasei CNCM I-5220-derived postbiotic (LP-PBF) in preserving intestinal barrier integrity. We demonstrated in vitro that LP-PBF restored the morphology of tight junctions (TJs) that were altered upon Salmonella typhimurium exposure. In vivo, LP-PBF protected the gut vascular barrier and blocked S. typhimurium dissemination into the bloodstream. Interestingly, we found that LP-PBF interacts not only with the host cells, but also directly with S. typhimurium blocking its biofilm formation, partially due to the presence of biosurfactants. This study highlights that LP-PBF is beneficial in maintaining gut homeostasis due to the synergistic effect of its different components. These results suggest that LP-PBF could be utilized in managing several pathologies displaying an impaired intestinal barrier function.

Pre-, pro-, syn-, and Postbiotics in Infant Formulas: What Are the Immune Benefits for Infants?

The first objective of infant formulas is to ensure the healthy growth of neonates and infants, as the sole complete food source during the first months of life when a child cannot be breastfed. Beyond this nutritional aspect, infant nutrition companies also try to mimic breast milk in its unique immuno-modulating properties. Numerous studies have demonstrated that the intestinal microbiota under the influence of diet shapes the maturation of the immune system and influences the risk of atopic diseases in infants. A new challenge for dairy industries is, therefore, to develop infant formulas inducing the maturation of immunity and the microbiota that can be observed in breastfed delivered vaginally, representing reference infants. Streptococcus thermophilus, Lactobacillus reuteri DSM 17938, Bifidobacterium breve (BC50), Bifidobacterium lactis Bb12, Lactobacillus fermentum (CECT5716), and Lactobacillus rhamnosus GG (LGG) are some of the probiotics added to infant formula, according to a literature review of the past 10 years. The most frequently used prebiotics in published clinical trials are fructo-oligosaccharides (FOSs), galacto-oligosaccharides (GOSs), and human milk oligosaccharides (HMOs). This review sums up the expected benefits and effects for infants of pre-, pro-, syn-, and postbiotics added to infant formula regarding the microbiota, immunity, and allergies.

Evidence on the Preventive Effects of the Postbiotic Derived from Cow's Milk Fermentation with Lacticaseibacillus paracasei CBA L74 against Pediatric Gastrointestinal Infections

Postbiotics are commonly defined as preparations of inanimate probiotics and/or their cellular components and/or their metabolites/end products that confer health benefits on the host. They have been suggested as a promising strategy to limit infectious diseases. Emerging evidence support the efficacy of the postbiotic derived from cow's milk fermentation with the probiotic Lacticaseibacillus paracasei CBAL74 (FM-CBAL74) in preventing pediatric infectious diseases. We aimed at reviewing the evidence available.

Postbiotics: From emerging concept to application

The microbiome innovation has resulted in an umbrella term, postbiotics, which refers to non-viable microbial cells, metabolic byproducts and their microbial components released after lysis. Postbiotics, modulate immune response, gene expression, inhibit pathogen binding, maintain intestinal barriers, help in controlling carcinogenesis and pathogen infections. Postbiotics have antimicrobial, antioxidant, and immunomodulatory properties with favorable physiological, immunological, neuro-hormonal, regulatory and metabolic reactions. Consumption of postbiotics relieves symptoms of various diseases and viral infections such as SARS-CoV-2. Postbiotics can act as alternatives for pre-probiotic specially in immunosuppressed patients, children and premature neonates. Postbiotics are used to preserve and enhance nutritional properties of food, elimination of biofilms and skin conditioning in cosmetics. Postbiotics have numerous advantages over live bacteria with no risk of bacterial translocation from the gut to blood, acquisition of antibiotic resistance genes. The process of extraction, standardization, transport, and storage of postbiotic is more natural. Bioengineering techniques such as fermentation technology, high pressure etc., may be used for the synthesis of different postbiotics. Safety assessment and quality assurance of postbiotic is important as they may induce stomach discomfort, sepsis and/or toxic shock. Postbiotics are still in their infancy compared to pre- and pro- biotics but future research in this field may contribute to improved physiological functions and host health. The current review comprehensively summarizes new frontiers of research in postbiotics.

Probiotic-Based Intervention in the Treatment of Ulcerative Colitis: Conventional and New Approaches

Although there are number of available therapies for ulcerative colitis (UC), many patients are unresponsive to these treatments or experience secondary failure during treatment. Thus, the development of new therapies or alternative strategies with minimal side effects is inevitable. Strategies targeting dysbiosis of gut microbiota have been tested in the management of UC due to the unquestionable role of gut microbiota in the etiology of UC. Advanced molecular analyses of gut microbiomes revealed evident dysbiosis in UC patients, characterized by a reduced biodiversity of commensal microbiota. Administration of conventional probiotic strains is a commonly applied approach in the management of the disease to modify the gut microbiome, improve intestinal barrier integrity and function, and maintain a balanced immune response. However, conventional probiotics do not always provide the expected health benefits to a patient. Their benefits vary significantly, depending on the type and stage of the disease and the strain and dose of the probiotics administered. Their mechanism of action is also strain-dependent. Recently, new candidates for potential next-generation probiotics have been discovered. This could bring to light new approaches in the restoration of microbiome homeostasis and in UC treatment in a targeted manner. The aim of this paper is to provide an updated review on the current options of probiotic-based therapies, highlight the effective conventional probiotic strains, and outline the future possibilities of next-generation probiotic and postbiotic supplementation and fecal microbiota transplantation in the management of UC.

In vitro assessment of the probiotic properties of an industrial preparation containing Lacticaseibacillus paracasei in the context of athlete health

Intense physical activity is often associated with undesirable physiological changes, including increased inflammation, transient immunodepression, increased susceptibility to infections, altered intestinal barrier integrity, and increased oxidative stress. Several trials suggested that probiotics supplementation may have beneficial effects on sport-associated gastro-intestinal and immune disorders. Recently, in a placebo-controlled human trial, the AminoAlta™ probiotic formulation (AApf) was demonstrated to increase the absorption of amino acids from pea protein, suggesting that the administration of AApf could overcome the compositional limitations of plant proteins. In this study, human cell line models were used to assess in vitro the potential capacity of AApf to protect from the physiological damages that an intense physical activity may cause. The obtained results revealed that the bacteria in the AApf have the ability to adhere to differentiated Caco-2 epithelial cell layer. In addition, the AApf was shown to reduce the activation of NF-κB in Caco-2 cells under inflammatory stimulation. Notably, this anti-inflammatory activity was enhanced in the presence of partially hydrolyzed plant proteins. The AApf also triggered the expression of cytokines by the THP-1 macrophage model in a dose-dependent manner. In particular, the expression of cytokines IL-1β, IL-6, and TNF-α was higher than that of the regulatory cytokine IL-10, resembling a cytokine profile characteristic of M1 phenotype, which typically intervene in counteracting bacterial and viral infections. Finally, AApf was shown to reduce transepithelial permeability and increase superoxide dismutase activity in the Caco-2 cell model. In conclusion, this study suggests that the AApf may potentially provide a spectrum of benefits useful to dampen the gastro-intestinal and immune detrimental consequences of an intense physical activity.

Anti-inflammatory effect a specific Lactiplantibacillus plantarum in an ovalbumin-induced asthma model

Autoimmune, allergic, and respiratory inflammatory diseases are some of the most important health issues worldwide. Disorders of the gut microbiota have been associated with the induction of allergic and inflammatory diseases, and probiotics are being tested for disease prevention. We examined functional Lactiplantibacillus plantarum RGU (Lp-1) to mice with ovalbumin (OVA)-induced asthma model to elucidate the inhibitory effect on pathological progression in asthma model. Prior to the experiments, the intestinal lactic acid bacteria were reduced by administering multiple antibiotics (MAB) to evaluate the administration effect of lactic acid bacteria. Mice were administered with Lp-1 or comparative control lactic acid bacteria in each group. After that, OVA-induced asthma was induced, and cytokine gene expression and histological findings were compared. Exacerbation of lung lesions was confirmed in the MAB group. The Lp-1 group mice had alleviated lung lesions with a decrease in IL-1β, IL-13, IL-17 and an increase in IL-10 of the splenocytes and bronchial lymph nodes compared with the MAB group, but not in the other groups. In OVA-induced asthma, administration of specific Lactiplantibacillus was confirmed to induce anti-inflammatory cytokines.

Lactobacillus acidophilus Mitigates Osteoarthritis-Associated Pain, Cartilage Disintegration and Gut Microbiota Dysbiosis in an Experimental Murine OA Model

To test probiotic therapy for osteoarthritis (OA), we administered Lactobacillus acidophilus (LA) by oral gavage (2×/week) after induction of OA by partial medial meniscectomy (PMM). Pain was assessed by von Frey filament and hot plate testing. Joint pathology and pain markers were comprehensively analyzed in knee joints, spinal cords, dorsal root ganglia and distal colon by Safranin O/fast green staining, immunofluorescence microscopy and RT-qPCR. LA acutely reduced inflammatory knee joint pain and prevented further OA progression. The therapeutic efficacy of LA was supported by a significant reduction of cartilage-degrading enzymes, pain markers and inflammatory factors in the tissues we examined. This finding suggests a likely clinical effect of LA on OA. The effect of LA treatment on the fecal microbiome was assessed by 16S rRNA gene amplicon sequencing analysis. LA significantly altered the fecal microbiota compared to vehicle-treated mice (PERMANOVA p < 0.009). Our pre-clinical OA animal model revealed significant OA disease modifying effects of LA as reflected by rapid joint pain reduction, cartilage protection, and reversal of dysbiosis. Our findings suggest that LA treatment has beneficial systemic effects that can potentially be developed as a safe OA disease-modifying drug (OADMD).

Postbiotics as the key mediators of the gut microbiota-host interactions

The priority of the Sustainable Development Goals for 2022 is to reduce all causes related to mortality. In this regard, microbial bioactive compounds with characteristics such as optimal compatibility and close interaction with the host immune system are considered a novel therapeutic approach. The fermentation process is one of the most well-known pathways involved in the natural synthesis of a diverse range of postbiotics. However, some postbiotics are a type of probiotic response behavior to environmental stimuli that usually play well-known biological roles. Also, postbiotics with unique structure and function are key mediators between intestinal microbiota and host cellular processes/metabolic pathways that play a significant role in maintaining homeostasis. By further understanding the nature of parent microbial cells, factors affecting their metabolic pathways, and the development of compatible extraction and identification methods, it is possible to achieve certain formulations of postbiotics with special efficiencies, which in turn will significantly improve the performance of health systems (especially in developing countries) toward a wide range of acute/chronic diseases. The present review aims to describe the fundamental role of postbiotics as the key mediators of the microbiota-host interactions. Besides, it presents the available current evidence regarding the interaction between postbiotics and host cells through potential cell receptors, stimulation/improvement of immune system function, and the enhancement of the composition and function of the human microbiome.

Backslopping Time, Rinsing of the Grains During Backslopping, and Incubation Temperature Influence the Water Kefir Fermentation Process

For eight backslopping steps, eight series of water kefir fermentation processes differing in backslopping time and rinsing of the grains during each backslopping step and eight series of fermentation processes differing in incubation temperature and backslopping time were followed. Short backslopping times resulted in high relative abundances of Liquorilactobacillus nagelii and Saccharomyces cerevisiae, intermediate backslopping times in high relative abundances of Leuconostoc pseudomesenteroides, and long backslopping times in high relative abundances of Oenococcus sicerae and Dekkera bruxellensis. When the grains were rinsed during each backslopping step, the relative abundances of Lentilactobacillus hilgardii and Leuc. pseudomesenteroides increased and those of D. bruxellensis and Liql. nagelii decreased. Furthermore, rinsing of the grains during each backslopping step resulted in a slightly higher water kefir grain growth and lower metabolite concentrations. The relative abundances of Liquorilactobacillus mali were highest at 17°C, those of Leuc. pseudomesenteroides at 21 and 25°C, and those of Liql. nagelii at 29°C. With a kinetic modeling approach, the impact of the temperature and rinsing of the grains during the backslopping step on the volumetric production rates of the metabolites was determined.

Protective effects of the postbiotic deriving from cow's milk fermentation with L. paracasei CBA L74 against Rotavirus infection in human enterocytes

Rotavirus (RV) is the leading cause of acute gastroenteritis-associated mortality in early childhood. Emerging clinical evidence suggest the efficacy of the postbiotic approach based on cow's milk fermentation with the probiotic Lacticaseibacillus paracasei CBAL74 (FM-CBAL74) in preventing pediatric acute gastroenteritis, but the mechanisms of action are still poorly characterized. We evaluated the protective action of FM-CBAL74 in an in vitro model of RV infection in human enterocytes. The number of infected cells together with the relevant aspects of RV infection were assessed: epithelial barrier damage (tight-junction proteins and transepithelial electrical resistance evaluation), and inflammation (reactive oxygen species, pro-inflammatory cytokines IL-6, IL-8 and TNF-α, and mitogen-activated protein kinase pathway activation). Pre-incubation with FM-CBA L74 resulted in an inhibition of epithelial barrier damage and inflammation mediated by mitogen-activated protein kinase pathway activation induced by RV infection. Modulating several protective mechanisms, the postbiotic FM-CBAL74 exerted a preventive action against RV infection. This approach could be a disrupting nutritional strategy against one of the most common killers for the pediatric age.

Effect of Novel Lactobacillus paracaesi microcapsule on growth performance, gut health and microbiome community of broiler chickens

The beneficial action of probiotics is questioned time and again due to the loss of their survivability under gastrointestinal conditions, particularly gastric acid. In this experiment, a probiotic species was encapsulated to improve its delivery to the distal parts, and its effects on production performance, gut health, and microbial profile in broilers were investigated. A total of 240 Arbor acres (AA) broilers were randomly allotted into 3 treatments with 8 replicate pens per treatment and 10 broilers in each pen for 42 d. Dietary treatments were 1) basal feed without any additives (CON), 2) CON+15 ppm Virginiamycin (ANT), and 3) CON+500 ppm encapsulated Lactobacillus paracaesi (ELP). The result showed that the addition of ELP to the feed did not affect growth performance and carcass characteristics significantly. However, ELP increased the ratio of villus height to crypt depth (P < 0.05) and mRNA expression of ZO-1 (P < 0.05) relative to the CON or ANT group. Similarly, qPCR showed that dietary supplementation of ELP raised gene expression of the anti-inflammatory cytokine and tended to decrease proinflammatory cytokines resulting improve in immunity. Moreover, chicks fed with ELP had lower malondialdehyde (MDA) (P < 0.05) than CON and lower reactive oxygen species (ROS) (P < 0.05) level than ANT in serum. In contrast, the total antioxidant capacity (TAOC) level was tended to increase. The ammonia level of ileum and cecum chyme was decreased (P < 0.05) in the ELP group than CON while the level of propionic acid of cecal content was increased (P < 0.05). 16S rRNA sequencing revealed the dietary treatment modulated the diversity and composition of cecal microflora. At the phylum level, Bacteroidetes was enriched, and Proteobacteria was depleted in the ELP group. At the genus level, ELP increased Bacteroides (P < 0.05) compared to control. The results indicate that oral delivery of probiotics via microcapsule could impart beneficial effects on birds and be used as an alternative to antibiotics.

Baseline Concentrations of Various Immune Biomarkers Determine Their Increase after Consumption of a Postbiotic Based on Cow’s Milk Fermented with Lactobacillus paracasei CBA L74 in Both Newborns and Young Children

Intake of a postbiotic product can support immunity depending on specific conditions of the consumer. The present study evaluates the potential impact of baseline values on the change of various immune factors (α-defensin, β-defensin, cathelicidin, and secretory IgA) after three months of consumption of a postbiotic based on cow’s milk fermented with Lactobacillus paracasei CBA L74 in a young population. For the analysis, raw data of three studies were used in a multivariate analysis applying confounding factors. One study in newborns demonstrated that intake of the postbiotic yielded an increase in the concentrations of α-defensin and secretory IgA (at least p < 0.02), while for all factors, except β-defensin, the higher the baseline values the lower the increase (at least p < 0.002). Two combined studies in young children (aged 1–4 years) showed an increase in the concentration of all factors after intake of the postbiotic (at least p < 0.003), but now showing the higher the baseline values the higher the increase after three months (at least p < 0.02) in only the postbiotic group. It is concluded that consumption of the postbiotic leads to a baseline- and age-dependent increase in the concentrations of the immune factors under study in both newborns and young children. It is hypothesized that maturation of the immune system leads to different effects on optimizing host defense factors via this postbiotic intake.

Effect of lactic acid bacteria isolated from some fermented dairy products on carbon tetrachloride-induced hepatotoxicity and nephrotoxicity of albino rats

The current research was performed to evaluate the potential protective effect of Lactobacillus paracasei ssp. paracasei, Pediococcus acidilactici, Lactococcus lactis ssp. lactis, and silymarin in the alleviation of health (hepatic and renal) complications caused by carbon tetrachloride (CCl₄) in rats. Healthy sixty albino rats were divided into six groups, the first group was control (negative), the second group (control positive) was injected CCl₄ (1 ml/kg, 1:1 v/v paraffin oil mixture, i.p. every third day for 8 weeks), the third group (CCl₄ + silymarin group) receiving both CCl₄ and daily silymarin therapy (50 mg/kg, oral), and the fourth group: CCl₄ + Lactobacillus paracasei (1 ml orally). The fifth group (CCl₄ + Pediococcus acidilactici 1 ml orally) and the sixth group (CCl₄ + Lactococcus lactis 1 ml orally) for 8 weeks per day. Biochemical markers were tested for blood, liver, and kidney tissue. Histopathological examination of the liver and kidney tissues was performed. The findings obtained have shown that Lactobacillus paracasei ssp. paracasei, Pediococcus acidilactici, and Lactococcus lactis ssp. lactis improved the disrupted biochemical parameters caused by CCl₄ therapy. Besides, the findings of the histopathology are in consistent with biochemical parameters and the protective ability of lactic acid bacteria suggesting that the best lactic acid bacteria were Pediococcus acidilactici that helped strengthen liver fibrosis caused by CCl₄ therapy, while the best bacterium for improving renal damage was Lactococcus lactis.

Probiotics and gut microbiota: mechanistic insights into gut immune homeostasis through TLR pathway regulation

Consumption of probiotics as a useful functional food improves the host's wellbeing, and, when paired with prebiotics (indigestible dietary fibre/carbohydrate), often benefits the host through anaerobic fermentation.

Precision Postbiotics and Mental Health: the Management of Post-COVID-19 Complications

The health catastrophe originated by COVID-19 pandemic construed profound impact on a global scale. However, a plethora of research studies corroborated convincing evidence conferring severity of infection of SARS-CoV-2 with the aberrant gut microbiome that strongly speculated its importance for development of novel therapeutic modalities. The intense exploration of probiotics has been envisaged to promote the healthy growth of the host, and restore intestinal microecological balance through various metabolic and physiological processes. The demystifying effect of probiotics cannot be defied, but there exists a strong skepticism related to their safety and efficacy. Therefore, molecular signature of probiotics termed as "postbiotics" are of paramount importance and there is continuous surge of utilizing postbiotics for enhancing health benefits, but little is explicit about their antiviral effects. Therefore, it is worth considering their prospective role in post-COVID regime that pave the way for exploring the pastoral vistas of postbiotics. Based on previous research investigations, the present article advocates prospective role of postbiotics in alleviating the health burden of viral infections, especially SARS-CoV-2. The article also posits current challenges and proposes a futuristic model describing the concept of "precision postbiotics" for effective therapeutic and preventive interventions that can be used for management of this deadly disease.

Protective effects elicited by cow milk fermented with L. Paracasei CBAL74 against SARS-CoV-2 infection in human enterocytes

Fermented foods have been proposed in limiting SARS-CoV-2 infection. Emerging evidence suggest the efficacy of cow's milk fermented with the probiotic L. paracasei CBAL74 (FM-CBAL74) in preventing infectious diseases. We evaluated the protective action of FM-CBAL74 against SARS-CoV-2 infection in human enterocytes. Relevant aspects of SARS-CoV-2 infection were assessed: infectivity, host functional receptor angiotensin-converting enzyme-2 (ACE2), transmembrane protease serine 2 (TMPRSS2), and pro-inflammatory cytokines expression (IL-6, IL-15, IL-1β, VEGFβ, TNF-α, MCP-1, CXCL1). Pre-incubation with FM-CBA L74 reduced the number of infected cells. The expression of ACE2 and the pro-inflammatory cytokines IL-6, VEGFβ, IL-15, IL-1β was downregulated by the pre-treatment with this fermented food. No effect on TMPRSS2, MCP-1, TNF-α and CXCL1 expression was observed. Modulating the crucial aspects of the infection, the fermented food FM-CBAL74 exerts a preventive action against SARS-CoV-2. These evidence could pave the way to innovative nutritional strategy to mitigate the COVID-19.

Involvement of Probiotics and Postbiotics in the Immune System Modulation

Intestinal microbiota interacts with other systems, especially the immune system, which is responsible for protecting the body by recognizing “stranger” (pathogen associated molecular patterns-PAMPs) and “danger” (damage-associated molecular patterns-DAMPs) molecular motifs. In this manner, it plays an important role in the pathogenesis of various diseases and health. Despite the use of probiotics that modulate the intestinal microbiota in providing health benefits and in the treatment of diseases, there are some possible concerns about the possibility of developing adverse effects, especially in people with suppressed immune systems. Since probiotics provide health benefits with bioactive compounds, studies are carried out on the use of products containing non-living probiotic microorganisms (paraprobiotics) and/or their metabolites (postbiotics) instead of probiotic products. It is even reported that these microbial compounds have more immunomodulatory activities than living microorganisms via some possible mechanism and eliminates some disadvantages of probiotics. Considering the increasing use of functional foods in health and disease, further studies are needed with respect to the benefits and advantages of parabiotic and/or postbiotic use in the food and pharmaceutical industry as well as immune system modulation. Although probiotics have been extensive studied for a long time, it seems that postbiotics are promising tools for future research and applications according to the recent literature. This review aimed to evaluate the interaction of probiotics and postbiotics with the immune systems and also their advantages and disadvantages in the area of food-pharmaceutical industry and immune system modulation.

Effect of probiotic fermented dairy products on incidence of respiratory tract infections: a systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Previous studies have suggested that the consumption of probiotic fermented dairy products (PFDP) may have a protective effect on respiratory tract infections (RTIs). However, the results of studies are inconclusive. We aimed to systematically investigate the effect of PFDP on RTIs by performing a meta-analysis of randomized controlled trials (RCTs).

METHODS

PubMed and Scopus databases were systematically searched up to October 2020 to identify eligible RCTs. Meta-analysis outcomes were risk of incidence of upper (URTIs ) and lower (LRTIs ) respiratory tract infections. A random-effects model was used to pool the relative risks (RR) and corresponding 95 % confidence intervals (CI) for outcomes following conception of PFDP.

RESULTS

A total of 22 RCTs, with a total sample size of 10,190 participants, were included in this meta-analysis. Compared with placebo, consumption of PFDP had a significant protective effect against RTIs in the overall analysis (RR = 0.81, 95 %CI: 0.74 to 0.89) and in children (RR = 0.82, 95 %CI: 0.73 to 0.93), adults (RR = 0.81, 95 %CI: 0.66 to 1.00), and elderly population (RR = 0.78, 95 %CI: 0.61 to 0.98). The significant decreased risk of RTIs was also observed for URTIs (RR = 0.83, 95 %CI: 0.73 to 0.93), while, this effect was marginal for LRTIs (RR = 0.78, 95 %CI: 0.60 to 1.01, P = 0.06). The disease-specific analysis showed that PFDP have a protective effect on pneumonia (RR = 0.76, 95 %CI: 0.61 to 0.95) and common cold (RR = 0.68, 95 %CI: 0.49 to 0.96).

CONCLUSIONS

Consumption of PFDP is a potential dietary approach for the prevention of RTIs.

Gut vascular barrier impairment leads to intestinal bacteria dissemination and colorectal cancer metastasis to liver

Metastasis is facilitated by the formation of a "premetastatic niche," which is fostered by primary tumor-derived factors. Colorectal cancer (CRC) metastasizes mainly to the liver. We show that the premetastatic niche in the liver is induced by bacteria dissemination from primary CRC. We report that tumor-resident bacteria Escherichia coli disrupt the gut vascular barrier (GVB), an anatomical structure controlling bacterial dissemination along the gut-liver axis, depending on the virulence regulator VirF. Upon GVB impairment, bacteria disseminate to the liver, boost the formation of a premetastatic niche, and favor the recruitment of metastatic cells. In training and validation cohorts of CRC patients, we find that the increased levels of PV-1, a marker of impaired GVB, is associated with liver bacteria dissemination and metachronous distant metastases. Thus, PV-1 is a prognostic marker for CRC distant recurrence and vascular impairment, leading to liver metastases.

Gastrointestinal biofilms in health and disease

Microorganisms colonize various ecological niches in the human habitat, as they do in nature. Predominant forms of multicellular communities called biofilms colonize human tissue surfaces. The gastrointestinal tract is home to a profusion of microorganisms with intertwined, but not identical, lifestyles: as isolated planktonic cells, as biofilms and in biofilm-dispersed form. It is therefore of major importance in understanding homeostatic and altered host-microorganism interactions to consider not only the planktonic lifestyle, but also biofilms and biofilm-dispersed forms. In this Review, we discuss the natural organization of microorganisms at gastrointestinal surfaces, stratification of microbiota taxonomy, biogeographical localization and trans-kingdom interactions occurring within the biofilm habitat. We also discuss existing models used to study biofilms. We assess the contribution of the host-mucosa biofilm relationship to gut homeostasis and to diseases. In addition, we describe how host factors can shape the organization, structure and composition of mucosal biofilms, and how biofilms themselves are implicated in a variety of homeostatic and pathological processes in the gut. Future studies characterizing biofilm nature, physical properties, composition and intrinsic communication could shed new light on gut physiology and lead to potential novel therapeutic options for gastrointestinal diseases.

In the Age of Viral Pandemic, Can Ingredients Inspired by Human Milk and Infant Nutrition Be Repurposed to Support the Immune System?

In 2020, with the advent of a pandemic touching all aspects of global life, there is a renewed interest in nutrition solutions to support the immune system. Infants are vulnerable to infection and breastfeeding has been demonstrated to provide protection. As such, human milk is a great model for sources of functional nutrition ingredients, which may play direct roles in protection against viral diseases. This review aims to summarize the literature around human milk (lactoferrin, milk fat globule membrane, osteopontin, glycerol monolaurate and human milk oligosaccharides) and infant nutrition (polyunsaturated fatty acids, probiotics and postbiotics) inspired ingredients for support against viral infections and the immune system more broadly. We believe that the application of these ingredients can span across all life stages and thus apply to both pediatric and adult nutrition. We highlight the opportunities for further research in this field to help provide tangible nutrition solutions to support one's immune system and fight against infections.

Postbiotic Supplementation for Children and Newborn's Health

It is now well known how the microbiota can positively or negatively influence humans health, depending on its composition. The microbiota's countless beneficial effects have allowed it to be defined as a genuine symbiont for our species. In an attempt to positively influence the microbiota, research has focused on probiotics and prebiotics. Probiotics are viable beneficial bacteria of various strains. Prebiotics are specific substances able to favor the development of advantageous bacteria strains. Postbiotics are a new category of compounds capable of affecting the microbiota. According to the different definitions, postbiotics include both nonviable bacteria and substances deriving from bacterial metabolism. Postbiotics are particularly promising in pediatric settings, as they offer some advantages over probiotics, including the absence of the risk of intestinal translocation or worsening of local inflammation. For these reasons, their use in fragile population categories such as newborns, and even more prematures, seems to be the best solution for improving microbiota's health in this population. This narrative review aims to collect the research conducted so far on postbiotics' potential in the first stages of life.

Improving Human Health with Milk Fat Globule Membrane, Lactic Acid Bacteria, and Bifidobacteria

The milk fat globule membrane (MFGM), the component that surrounds fat globules in milk, and its constituents have gained significant attention for their gut function, immune-boosting properties, and cognitive-development roles. The MFGM can directly interact with probiotic bacteria, such as bifidobacteria and lactic acid bacteria (LAB), through interactions with bacterial surface proteins. With these interactions in mind, increasing evidence supports a synergistic effect between MFGM and probiotics to benefit human health at all ages. This important synergy affects the survival and adhesion of probiotic bacteria through gastrointestinal transit, mucosal immunity, and neurocognitive behavior in developing infants. In this review, we highlight the current understanding of the co-supplementation of MFGM and probiotics with a specific emphasis on their interactions and colocalization in dairy foods, supporting in vivo and clinical evidence, and current and future potential applications.

Functional characterization and immunomodulatory properties of Lactobacillus helveticus strains isolated from Italian hard cheeses

Lactobacillus helveticus carries many properties such as the ability to survive gastrointestinal transit, modulate the host immune response, accumulate biopeptides in milk, and adhere to the epithelial cells that could contribute to improving host health. In this study, the applicability as functional cultures of four L. helveticus strains isolated from Italian hard cheeses was investigated. A preliminary strain characterization showed that the ability to produce folate was generally low while antioxidant, proteolytic, peptidase, and β-galactosidase activities resulted high, although very variable, between strains. When stimulated moDCs were incubated in the presence of live cells, a dose-dependent release of both the pro-inflammatory cytokine IL-12p70 and the anti-inflammatory cytokine IL-10, was shown for all the four strains. In the presence of cell-free culture supernatants (postbiotics), a dose-dependent, decrease of IL-12p70 and an increase of IL-10 was generally observed. The immunomodulatory effect took place also in Caciotta-like cheese made with strains SIM12 and SIS16 as bifunctional (i.e., immunomodulant and acidifying) starter cultures, thus confirming tests in culture media. Given that the growth of bacteria in the cheese was not necessary (they were killed by pasteurization), the results indicated that some constituents of non-viable bacteria had immunomodulatory properties. This study adds additional evidence for the positive role of L. helveticus on human health and suggests cheese as a suitable food for delivering candidate strains and modulating their anti-inflammatory properties.

Postbiotics against Pathogens Commonly Involved in Pediatric Infectious Diseases

The Sustainable Development goals for 2020 included reducing all causes associated with infant and perinatal mortality in their priorities. The use of compounds with bioactive properties has been proposed as a therapeutic strategy due to their stimulating effect on the host's immune system. Additionally, biotherapeutic products such as postbiotics, tentatively defined as compounds produced during a fermentation process that support health and well-being, promote intestinal barrier integrity without posing considerable risks to children's health. Although this is a concept in development, there are increasing studies in the field of nutrition, chemistry, and health that aim to understand how postbiotics can help prevent different types of infections in priority populations such as minors under the age of five. The present review aims to describe the main mechanisms of action of postbiotics. In addition, it presents the available current evidence regarding the effects of postbiotics against pathogens commonly involved in pediatric infections. Postbiotics may constitute a safe alternative capable of modulating the cellular response and stimulating the host's humoral response.

Postbiotic-Enabled Targeting of the Host-Microbiota-Pathogen Interface: Hints of Antibiotic Decline?

Mismanagement of bacterial infection therapies has undermined the reliability and efficacy of antibiotic treatments, producing a profound crisis of the antibiotic drug market. It is by now clear that tackling deadly infections demands novel strategies not only based on the mere toxicity of anti-infective compounds. Host-directed therapies have been the first example as novel treatments with alternate success. Nevertheless, recent advances in the human microbiome research have provided evidence that compounds produced by the microbial metabolism, namely postbiotics, can have significant impact on human health. Such compounds target the host-microbe-pathogen interface rescuing biotic and immune unbalances as well as inflammation, thus providing novel therapeutic opportunities. This work discusses critically, through literature review and personal contributions, these novel nonantibiotic treatment strategies for infectious disease management and resistance prevention, which could represent a paradigm change rocking the foundation of current antibiotic therapy tenets.

Postbiotics and paraprobiotics: A review of current evidence and emerging trends

In recent years, new probiotic-related concepts such as postbiotics and paraprobiotics have been coined to indicate that non-viable microorganisms or bacterial-free extracts may provide benefits to the host by offering additional bioactivities to probiotics, including but not limited to anti-inflammatory, immunomodulatory, anti-proliferative and antioxidant activities. Despite in vitro and in vivo studies that support the promising use of postbiotics and paraprobiotics as health promoters, the mechanism of action and the signaling pathway involved have not yet been fully elucidated. Therefore, the aim of this chapter is to provide an overview of novel probiotic-related concepts and the scientific evidence that supports their bioactivities as well as the possible mechanisms underlying their health-promoting effects. Additionally, current trends in food, feed, and pharmaceutical applications are discussed.

Regulatory Effect of Lactobacillus brevis Bmb6 on Gut Barrier Functions in Experimental Colitis

The integrity of gut barrier functions is closely associated with the pathogenesis of colitis. It is speculated that Lactobacillus brevis Bmb6 alleviates colitis by improving the tight junction (TJ) of the inflamed intestinal epithelial layer. In the present study, the regulatory effects of L. brevis Bmb6 on the TJ barrier to ameliorate colitis-symptoms were investigated. Preliminary screening showed that L. brevis Bmb6 exhibited strong acid and bile acid tolerance, along with antioxidants and β-galactosidase activities. In a 14-day dextran sulfate sodium (DSS)-induced colitis mouse model, treatment with L. brevis Bmb6 significantly decreased in the disease activity index score. In addition, histological analyses showed that treatment with L. brevis Bmb6 protected the structural integrity of the intestinal epithelial layer and mucin-secreting goblet cells from DSS-induced damage, with only slight infiltration of immune cells. Interestingly, western blotting analyses showed that the expression of the TJ protein, zona occluden-1, was restored in Bmb6-treated mice, but not in DSS-induced mice. Consistently, the gene expression of inflammatory cytokines (tumor necrosis factor-α and interferon-γ) was also suppressed in the Bmb6-treated mice. Hence, our findings suggest that suppression of inflammatory conditions enhanced expression of TJ protein, ZO-1, or vice versa, contributing to a colitis-ameliorating effect in L. brevis Bmb6.

Bio-functional properties of probiotic Lactobacillus: current applications and research perspectives

Lactic acid bacteria as a starter culture are very important component in the fermentation process of dairy and food industry. Application of lactic acid bacteria as probiotic bacteria adds more functionality to the developed product. Gut colonizing bacteria have attractive benefits related to human health. Bio-functional properties such as antimicrobial activity, anti-inflammatory, ACE-inhibitory, antioxidant, antidiarrheal, antiviral, immunomodulatory, hypocholesterolemic, anti-diabetic and anti-cancer activities are the most applicable research areas of lactic acid bacteria. Different strains of Lactobacillus are generally consumed as probiotics and colonize the gastrointestinal tract. Sometimes these bacteria may possess antimicrobial activity and may positively influence the effect of antibiotics. Use of Lactobacillus spp. for the development of functional foods is one of the promising areas of current research and applications. Individual bacterial species have unique biological activity, which may vary from strains to strains and identification of this uniqueness could be helpful in the development of functional and therapeutic food products.

Analysis of immune, microbiota and metabolome maturation in infants in a clinical trial of Lactobacillus paracasei CBA L74-fermented formula

Mother’s milk is the best choice for infants nutrition, however when it is not available or insufficient to satisfy the needs of the infant, formula is proposed as an effective substitute. Here, we report the results of a randomized controlled clinical trial (NCT03637894) designed to evaluate the effects of two different dietary regimens (standard formula and Lactobacillus paracasei CBA L74-fermented formula) versus breastfeeding (reference group) on immune defense mechanisms (primary endpoint: secretory IgA, antimicrobial peptides), the microbiota and its metabolome (secondary outcomes), in healthy full term infants according to the type of delivery (n = 13/group). We show that the fermented formula, safe and well tolerated, induces an increase in secretory IgA (but not in antimicrobial peptides) and reduces the diversity of the microbiota, similarly, but not as much as, breastmilk. Metabolome analysis allowed us to distinguish subjects based on their dietary regimen and mode of delivery. Together, these results suggest that a fermented formula favors the maturation of the immune system, microbiota and metabolome.

Milk breastfeeding and prebiotic-supplemented formulas have varying effects on the infant gut microbiome. Here, in a randomized controlled clinical trial, the authors investigate the effects of a Lactobacillus paracasei-fermented formula on the immune defense mechanisms, microbiota and its metabolome in full term infants.

Dairy Propionibacterium freudenreichii ameliorates acute colitis by stimulating MUC2 expression in intestinal goblet cell in a DSS-induced colitis rat model

An intact mucus layer is important in managing inflammatory bowel disease (IBD). Dairy Propionibacterium freudenreichii has probiotic potential, produces propionic acid and is known to promote health. The aim of this study was to evaluate the effects of P. freudenreichii on the improvement of colitis. LS 174T goblet cells and a dextran sodium sulfate (DSS)-induced colitis rat model were used to investigate the P. freudenreichii-induced stimulation of mucin production in vitro and in vivo, respectively. The mRNA and protein expression levels of MUC2, a main component of intestinal mucus, increased in the supernatant of P. freudenreichii culture (SPFC)-treated LS 174 cells. The SPFC and live P. freudenreichii (LPF) reduced the disease activity index (DAI) in the rats with DSS-induced colitis. After treatment with SPFC or LPF, the mRNA levels of typical pro-inflammatory cytokines decreased and the inflammatory state was histologically improved in the rats with DSS-induced colitis. The SPFC and LPF treatments increased the gene and protein expression levels of MUC2 in the rats with DSS-induced colitis compared with the expression levels in the negative control rats, and immunohistochemistry (IHC) showed an increase of the intestinal MUC2 level. In addition, SPFC and LPF augmented the level of propionate in the faeces of the rats with DSS-induced colitis. In conclusion, P. freudenreichii might improve acute colitis by restoring goblet cell number and stimulating the expression of MUC2 in intestinal goblet cells.

Lactobacillus paracasei-derived extracellular vesicles attenuate the intestinal inflammatory response by augmenting the endoplasmic reticulum stress pathway

Lactobacillus paracasei is a major probiotic and is well known for its anti-inflammatory properties. Thus, we investigated the effects of L. paracasei-derived extracellular vesicles (LpEVs) on LPS-induced inflammation in HT29 human colorectal cancer cells and dextran sulfate sodium (DSS)-induced colitis in C57BL/6 mice. ER stress inhibitors (salubrinal or 4-PBA) or CHOP siRNA were utilized to investigate the relationship between LpEV-induced endoplasmic reticulum (ER) stress and the inhibitory effect of LpEVs against LPS-induced inflammation. DSS (2%) was administered to male C57BL/6 mice to induce inflammatory bowel disease, and disease activity was measured by determining colon length, disease activity index, and survival ratio. In in vitro experiments, LpEVs reduced the expression of the LPS-induced pro-inflammatory cytokines IL-1α, IL-1β, IL-2, and TNFα and increased the expression of the anti-inflammatory cytokines IL-10 and TGFβ. LpEVs reduced LPS-induced inflammation in HT29 cells and decreased the activation of inflammation-associated proteins, such as COX-2, iNOS and NFκB, as well as nitric oxide. In in vivo mouse experiments, the oral administration of LpEVs also protected against DSS-induced colitis by reducing weight loss, maintaining colon length, and decreasing the disease activity index (DAI). In addition, LpEVs induced the expression of endoplasmic reticulum (ER) stress-associated proteins, while the inhibition of these proteins blocked the anti-inflammatory effects of LpEVs in LPS-treated HT29 cells, restoring the pro-inflammatory effects of LPS. This study found that LpEVs attenuate LPS-induced inflammation in the intestine through ER stress activation. Our results suggest that LpEVs have a significant effect in maintaining colorectal homeostasis in inflammation-mediated pathogenesis.

Tiny vesicles released by a bacterial species found in the human gut can reduce symptoms of inflammatory bowel disease (IBD) and prevent disease progression. People with IBD have a decreased abundance of Lactobacilli bacteria in their gut, creating an imbalance that perpetuates the disease. Replenishment of this bacteria may become a valuable therapy. Chang Mo Moon at Ewha Womans University, Yoon-Keun Kim at MD Healthcare, both in Seoul, South Korea, and co-workers demonstrated how extracellular vesicles (EVs) released by Lactobacilli paracasei can actively prevent bowel inflammation. These EVs contain a mixture of proteins, nucleic acids and other biomolecules. The team administered EV to cultured human colorectal cancer cells and to mice with induced colitis. The EVs decreased pro-inflammatory protein activity and boosted levels of protective cellular membrane proteins via augmenting ER stress pathway.

Postbiotics and Their Potential Applications in Early Life Nutrition and Beyond

Postbiotics are functional bioactive compounds, generated in a matrix during fermentation, which may be used to promote health. The term postbiotics can be regarded as an umbrella term for all synonyms and related terms of these microbial fermentation components. Therefore, postbiotics can include many different constituents including metabolites, short-chain fatty acids (SCFAs), microbial cell fractions, functional proteins, extracellular polysaccharides (EPS), cell lysates, teichoic acid, peptidoglycan-derived muropeptides and pili-type structures. Postbiotics is also a rather new term in the '-biotics' field. Where consensus exists for the definitions of pre- and probiotics, this is not yet the case for postbiotics. Here we propose a working definition and review currently known postbiotic compounds, their proposed mechanisms, clinical evidence and potential applications. Research to date indicates that postbiotics can have direct immunomodulatory and clinically relevant effects and evidence can be found for the use of postbiotics in healthy individuals to improve overall health and to relief symptoms in a range of diseases such as infant colic and in adults atopic dermatitis and different causes of diarrhea.

Effect of fermented milk from Lactococcus lactis ssp. cremoris strain JFR1 on Salmonella invasion of intestinal epithelial cells

The process of fermentation contributes to the organoleptic properties, preservation, and nutritional benefits of food. Fermented food may interfere with pathogen infections through a variety of mechanisms, including competitive exclusion or improving intestinal barrier integrity. In this study, the effect of milk fermented with Lactococcus lactis ssp. cremoris JFR1 on Salmonella invasion of intestinal epithelial cell cultures was investigated. Epithelial cells (HT29-MTX, Caco-2, and cocultures of the 2) were treated for 1 h with Lactococcus lactis ssp. cremoris JFR1 fermented milk before infection with Salmonella enterica ssp. enterica Typhimurium. Treatment with fermented milk resulted in increased transepithelial electrical resistance, which remained constant for the duration of infection (up to 3 h), illustrating a protective effect. After gentamicin treatment to remove adhered bacterial cells, enumeration revealed a reduction in numbers of intracellular Salmonella. Quantitative reverse-transcription PCR data indicated a downregulation of Salmonella virulence genes hilA, invA, and sopD after treatment with fermented milk. Fermented milk treatment of epithelial cells also exhibited an immunomodulatory effect reducing the production of proinflammatory IL-8. In contrast, chemically acidified milk (glucono delta-lactone) failed to show the same effect on monolayer integrity, Salmonella Typhimurium invasion, and gene expression as well as immune modulation. Furthermore, an oppA knockout mutant of Salmonella Typhimurium infecting treated epithelial cells did not show suppressed virulence gene expression. Collectively, these results suggest that milk fermented with Lactococcus lactis ssp. cremoris JFR1 is effective in vitro in the reduction of Salmonella invasion into intestinal epithelial cells. A functional OppA permease in Salmonella is required to obtain the antivirulence effect of fermented milk.

Celiac disease-associated Neisseria flavescens decreases mitochondrial respiration in CaCo-2 epithelial cells: Impact of Lactobacillus paracasei CBA L74 on bacterial-induced cellular imbalance

We previously identified a Neisseria flavescens strain in the duodenum of celiac disease (CD) patients that induced immune inflammation in ex vivo duodenal mucosal explants and in CaCo‐2 cells. We also found that vesicular trafficking was delayed after the CD‐immunogenic P31‐43 gliadin peptide‐entered CaCo‐2 cells and that Lactobacillus paracasei CBA L74 (L. paracasei‐CBA) supernatant reduced peptide entry. In this study, we evaluated if metabolism and trafficking was altered in CD‐N. flavescens‐infected CaCo‐2 cells and if any alteration could be mitigated by pretreating cells with L. paracasei‐CBA supernatant, despite the presence of P31‐43. We measured CaCo‐2 bioenergetics by an extracellular flux analyser, N. flavescens and P31‐43 intracellular trafficking by immunofluorescence, cellular stress by TBARS assay, and ATP by bioluminescence. We found that CD‐N. flavescens colocalised more than control N. flavescens with early endocytic vesicles and more escaped autophagy thereby surviving longer in infected cells. P31‐43 increased colocalisation of N. flavescens with early vesicles. Mitochondrial respiration was lower (P < .05) in CD‐N. flavescens‐infected cells versus not‐treated CaCo‐2 cells, whereas pretreatment with L. paracasei‐CBA reduced CD‐N. flavescens viability and improved cell bioenergetics and trafficking. In conclusion, CD‐N. flavescens induces metabolic imbalance in CaCo‐2 cells, and the L. paracasei‐CBA probiotic could be used to correct CD‐associated dysbiosis.

Nutrimune and immune defence against pathogens in the gastrointestinal and upper respiratory tracts: evaluation of a health claim pursuant to Article 14 of Regulation (EC) No 1924/2006

Following an application from H.J. Heinz Supply Chain Europe B.V. submitted for authorisation of a health claim pursuant to Article 14 of Regulation (EC) No 1924/2006 via the Competent Authority of the Netherlands, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on the scientific substantiation of a health claim related to Nutrimune and immune defence against pathogens in the gastrointestinal (GI) tract and upper respiratory tract (URT). The food Nutrimune (a pasteurised cow's skim milk fermented with Lactobacillus paracasei CBA L74) which is the subject of the health claim is sufficiently characterised. The Panel considers that immune defence against pathogens in GI tract and URT is a beneficial physiological effect. Two human intervention studies were submitted as being pertinent to the claim, which were evaluated by the Panel in the previous application. One human intervention study from which conclusions could be drawn showed an effect of Nutrimune on immune defence against pathogens in the GI tract and the URT. The post hoc re‐analysis of the two human studies combined does not address the methodological limitations of the second study raised in the previous opinion, i.e. that the study was not planned, designed, randomised and analysed as a multicentre study, and that the large disparity of subjects in the three centres was not duly justified. The results from one animal study could support an effect of Nutrimune on defence against pathogens in the GI tract. No evidence was provided for a plausible mechanism by which Nutrimune could exert the claimed effect in vivo in humans. The Panel concludes that the evidence provided is insufficient to establish a cause and effect relationship between the consumption of Nutrimune and immune defence against pathogens in the GI tract and URT.