The Role of Postbiotics in Asthma Treatment

In recent years, there has been abundant research concerning human microbiome and its impact on the host's health. Studies have shown that not only the commensal bacteria itself, but also postbiotics, understood as inanimate microorganisms, possibly with the presence of their components, may themselves have an effect on various elements of human physiology. In this review, we take a closer look at the specific ways in which postbiotics can alter immune response in allergic asthma, which is one of the most prevalent allergic diseases in today's world and a serious subject of concern. Through altering patients' immune response, not only to allergens but also to pathogens, postbiotics could have a significant role in lowering the number of asthma exacerbations. We suggest that more profound research should be undertaken in order to launch postbiotics into clinical standards of asthma treatment, given the greatly promising findings in terms of their immunomodulating potential.

Mechanistic insights into the role of probiotics in modulating immune cells in ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is a persistent inflammatory disorder that affects the gastrointestinal tract, mainly the colon, which is defined by inflammatory responses and the formation of ulcers. Probiotics have been shown to directly impact various immune cells, including dendritic cells (DCs), macrophages, natural killer (NK) cells, and T and B cells. By interacting with cell surface receptors, they regulate immune cell activity, produce metabolites that influence immune responses, and control the release of cytokines and chemokines.

METHODS

This article is a comprehensive review wherein we conducted an exhaustive search across published literature, utilizing reputable databases like PubMed and Web of Science. Our focus centered on pertinent keywords, such as "UC," 'DSS," "TNBS," "immune cells," and "inflammatory cytokines," to compile the most current insights regarding the therapeutic potential of probiotics in managing UC.

RESULTS

This overview aims to provide readers with a comprehensive understanding of the effects of probiotics on immune cells in relation to UC. Probiotics have a crucial role in promoting the proliferation of regulatory T cells (Tregs), which are necessary for preserving immunological homeostasis and regulating inflammatory responses. They also decrease the activation of pro-inflammatory cells like T helper 1 (Th1) and Th17 cells, contributing to UC development. Thus, probiotics significantly impact both direct and indirect pathways of immune cell regulation in UC, promoting Treg differentiation, inhibiting pro-inflammatory cell activation, and regulating cytokine and chemokine release.

CONCLUSION

Probiotics demonstrate significant potential in modulating the immune reactions in UC. Their capacity to modulate different immune cells and inflammation-related processes makes them a promising therapeutic approach for managing UC. However, further studies are warranted to optimize their use and fully elucidate the molecular mechanisms underlying their beneficial effects in UC treatment.

Novel perspective on the regulation of food allergy by probiotic: The potential of its structural components

Food allergy (FA) is a global public health issue with growing prevalence. Increasing evidence supports the strong correlation between intestinal microbiota dysbiosis and food allergies. Probiotic intervention as a microbiota-based therapy could alleviate FA effectively. In addition to improving the intestinal microbiota disturbance and affecting microbial metabolites to regulate immune system, immune responses induced by the recognition of pattern recognition receptors to probiotic components may also be one of the mechanisms of probiotics protecting against FA. In this review, it is highlighted in detail about the regulatory effects on the immune system and anti-allergic potential of probiotic components including the flagellin, pili, peptidoglycan, lipoteichoic acid, exopolysaccharides, surface (S)-layer proteins and DNA. Probiotic components could enhance the function of intestinal epithelial barrier as well as regulate the balance of cytokines and T helper (Th) 1/Th2/regulatory T cell (Treg) responses. These evidences suggest that probiotic components could be used as nutritional or therapeutic agents for maintaining immune homeostasis to prevent FA, which will contribute to providing new insights into the resolution of FA and better guidance for the development of probiotic products.

FK506 and Lactobacillus acidophilus ameliorate acute graft-versus-host disease by modulating the T helper 17/regulatory T-cell balance

Background

Graft-versus-host disease (GvHD) is a critical complication after allogeneic hematopoietic stem cell transplantation (HSCT). The immunosuppressants given to patients undergoing allogeneic HSCT disturb the microbiome and the host immune system, potentially leading to dysbiosis and inflammation, and may affect immune function and bone marrow transplantation. The intestinal microbiome is a target for the development of novel therapies for GvHD. Lactobacillus species are widely used supplements to induce production of antimicrobial and anti-inflammatory factors.

Methods

We determined the effect of the combination of Lactobacillus acidophilus and FK506 on GvHD following major histocompatibility complex-mismatched bone marrow transplantation.

Results

The combination treatment suppressed IFN-γ and IL-17-producing T cell differentiation, but increased Foxp3⁺Treg differentiation and IL-10 production. Also, the combination treatment and combination treated-induced Treg cells modulated the proliferation of murine alloreactive T cells in vitro. Additionally, the combination treatment upregulated Treg-related genes—Nt5e, Foxp3, Ikzf2, Nrp1 and Itgb8—in murine CD4⁺-T cells. The combination treatment also alleviated GvHD clinically and histopathologically by controlling the effector T cell and Treg balance in vivo. Moreover, the combination treatment decreased Th17 differentiation significantly and significantly upregulated Foxp3 and IL-10 expression in peripheral blood mononuclear cells from healthy controls and liver transplantation (LT) patients.

Conclusions

Therefore, the combination of L. acidophilus and FK506 is effective and safe for patients undergoing allogeneic hematopoietic stem cell transplantation.

Effect of Lactiplantibacillus plantarum HM-22 on immunoregulation and intestinal microbiota in α-lactalbumin-induced allergic mice

Milk protein is one of the eight major allergens, and α-lactalbumin (α-LA) is one of the major allergens of bovine milk protein. Our previous studies found that Lactiplantibacillus plantarum HM-22 (L. plantarum HM-22) showed a good gastrointestinal survival rate and intestinal colonization. To investigate the effect of L. plantarum HM-22 on intestinal inflammation and intestinal microbiota in α-LA-induced allergic mice, in this study, L. plantarum HM-22 at low and high doses was intragastrically administered to α-LA-induced allergic mice for 5 weeks. The results showed that L. plantarum HM-22 significantly relieved the weight loss and organ index of α-LA-induced allergic mice (p < 0.05). L. plantarum HM-22 increased the levels of interleukin-10 (IL-10), interferon-γ (IFN-γ) and transforming growth factor-β (TGF-β) in the serum of α-LA-induced allergic mice and decreased the levels of total immunoglobulin E (IgE) and the proinflammatory factor interleukin-4 (IL-4) (p < 0.05). The crypt structure of the colon tissues of α-LA-induced allergic mice changed, goblet cells decreased, and the phenomenon of a large number of inflammatory corpuscles that appeared was improved and alleviated with the intervention of L. plantarum HM-22 by hematoxylin-eosin (HE) staining. Western blot analysis showed that L. plantarum HM-22 significantly increased the expression of occludin and claudin-1 in the colon of α-LA-induced allergic mice and decreased the expression of the inflammatory proteins p65 and IκBα (p < 0.05). The intestinal microbiota of mice in each group was determined by 16S rRNA amplicon sequencing, and the results showed that intervention with L. plantarum HM-22 improved the intestinal microbes of α-LA-induced allergic mice. Spearman's correlation analysis revealed the correlation between intestinal microbiota changes and the α-LA-induced allergy-related index. This study provides a theoretical basis for probiotics to prevent allergies by changing the intestinal microbiota.

Modulatory Effects of Probiotics During Pathogenic Infections With Emphasis on Immune Regulation

In order to inhibit pathogenic complications and to enhance animal and poultry growth, antibiotics have been extensively used for many years. Antibiotics applications not only affect target pathogens but also intestinal beneficially microbes, inducing long-lasting changes in intestinal microbiota associated with diseases. The application of antibiotics also has many other side effects like, intestinal barrier dysfunction, antibiotics residues in foodstuffs, nephropathy, allergy, bone marrow toxicity, mutagenicity, reproductive disorders, hepatotoxicity carcinogenicity, and antibiotic-resistant bacteria, which greatly compromise the efficacy of antibiotics. Thus, the development of new antibiotics is necessary, while the search for antibiotic alternatives continues. Probiotics are considered the ideal antibiotic substitute; in recent years, probiotic research concerning their application during pathogenic infections in humans, aquaculture, poultry, and livestock industry, with emphasis on modulating the immune system of the host, has been attracting considerable interest. Hence, the adverse effects of antibiotics and remedial effects of probiotics during infectious diseases have become central points of focus among researchers. Probiotics are live microorganisms, and when given in adequate quantities, confer good health effects to the host through different mechanisms. Among them, the regulation of host immune response during pathogenic infections is one of the most important mechanisms. A number of studies have investigated different aspects of probiotics. In this review, we mainly summarize recent discoveries and discuss two important aspects: (1) the application of probiotics during pathogenic infections; and (2) their modulatory effects on the immune response of the host during infectious and non-infectious diseases.

Relationship between gut microbiota composition and sensitization to inhaled allergens

BACKGROUND

An imbalance in gut microbiota is implicated in several pathological conditions, including allergic diseases. This study investigates the association between gut microbiota composition and sensitization to two inhaled antigens.

METHODS

The study comprised 1109 local residents who had participated in the Iwaki Health Promotion Project in 2016. Blood samples were analyzed for levels of antigen-specific IgE against Japanese cedar pollen (JCP) and house dust (HD1). Fecal samples were analyzed for bacterial 16S rRNA (ribosomal ribonucleic acid) using next generation sequencing. The percent composition of gut microbes was compared between patients sensitized and unsensitized group for JCP and HD1 to determine whether the rate of sensitization to inhaled antigens associates with specific bacterial orders composing the gut microbiota.

RESULTS

In participants aged 20-49 years, the percent composition of Bacteroidales was significantly higher among participants sensitized to JCP than in those unsensitized. The percent composition of Lactobacillales was significantly higher in participants unsensitized to HD group than in those sensitized to that antigen. In addition, participants with low Bacteroidales and high Bifidobacteriales or Lactobacillales has low sensitization rates to HD compared with high Bacteroidales and low Bifidobacteriales or Lactobacillales.

CONCLUSIONS

The presence of bacteria of order Lactobacillales, Bifidobacteriales, and Bacteroidales in the gut microbiota may affect sensitization to inhaled allergens.

Modulation effect of Lactobacillus acidophilus KLDS 1.0738 on gut microbiota and TLR4 expression in β-lactoglobulin-induced allergic mice model

OBJECTIVES

β-lactoglobulin (β-Lg)-sensitized mice model was employed to investigate the correlation between Lactobacillus acidophilus KLDS 1.0738 (Lap KLDS 1.0738) modulating gut microbiota and inducting Toll-like receptors (TLRs) expression.

METHODS

The alterations of mice fecal microbiota were analyzed by 16S rRNA gene sequencing. The serum cytokines production and TLR4/NF-κB mRNA expression in the colon tissues were measured by ELISA kit and quantitative RT-PCR, respectively.

RESULTS

The results showed that Lap KLDS 1.0738 pretreatment attenuated β-Lg-induced hypersensitivity, accompanied with a diminished expression of TLR4/NF-κB signaling. Moreover, oral administration of Lap KLDS 1.0738 improved the richness and diversity of fecal microbiota, which was characterized by fewer Proteobacteria phylum and Helicobacteraceae family, and higher Firmicutes phylum and Lachnospiraceae family than allergic group. Notably, TLR4/NF-κB expression was positively correlated with the family of Helicobacteraceae in allergic group, but negatively correlated with the family of Lachnospiraceae, Ruminococcaceae and anti-inflammatory cytokines level. A significant positive correlation was observed between TLR4/NF-κB expression and the production of histamine, total IgE and pro-inflammatory cytokines.

CONCLUSIONS

Intake of Lap KLDS 1.0738 can influence the gut bacterial composition, which might result in recognizing TLRs signaling so as to inhibit allergic response.

Modulatory effect of Lactobacillus acidophilus KLDS 1.0738 on intestinal short-chain fatty acids metabolism and GPR41/43 expression in β-lactoglobulin-sensitized mice

We investigated the correlation between the beneficial effect of Lactobacillus acidophilus on gut microbiota composition, metabolic activities, and reducing cow's milk protein allergy. Mice sensitized with β-lactoglobulin (β-Lg) were treated with different doses of L. acidophilus KLDS 1.0738 for 4 weeks, starting 1 week before allergen induction. The results showed that intake of L. acidophilus significantly suppressed the hypersensitivity responses, together with increased fecal microbiota diversity and short-chain fatty acids (SCFAs) concentration (including propionate, butyrate, isobutyrate, and isovalerate) when compared with the allergic group. Moreover, treatment with L. acidophilus induced the expression of SCFAs receptors, G-protein-coupled receptors 41 (GPR41) and 43 (GPR43), in the spleen and colon of the allergic mice. Further analysis revealed that the GPR41 and GPR43 messenger RNA expression both positively correlated with the serum concentrations of transforming growth factor-β and IFN-γ (p < .05), but negatively with the serum concentrations of IL-17, IL-4, and IL-6 in the L. acidophilus-treated group compared with the allergic group (p < .05). These results suggested that L. acidophilus protected against the development of allergic inflammation by improving the intestinal flora, as well as upregulating SCFAs and their receptors GPR41/43.

Effect of Lactobacillus acidophilus KLDS 1.0738 on miRNA expression in in vitro and in vivo models of β-lactoglobulin allergy

This study aims to investigate the correlation between the ability of L. acidophilus to modulate miRNA expression and prevent Th17-dominated β-lactoglobulin (β-Lg) allergy. In vitro immunomodulation was evaluated by measuring splenocyte proliferation, Th17-related immune response and miRNA expression in β-Lg-sensitized splenocytes cultured with live L. acidophilus. Next, the allergic mouse model was used to evaluate anti-allergy capability of lactobacilli. The β-Lg challenge led to induction of up-regulation of miR-146a, miR-155, miR-21 and miR-9 expression in both in vivo and in vitro, along with increased Th17-related cytokine levels and mRNA expression of RORγt and IL-17. However, treatment of live L. acidophilus significantly suppressed hypersensitivity responses and Th17 cell differentiation. Moreover, administration of live L. acidophilus reduced expression of four miRNAs, especially miR-146a and miR-155. In addition, the decreased expression of the miRNAs in the spleen of the L. acidophilus-treated group was closely associated with decrease of IL-17 and RORγt mRNA expression.

Supplementation of a Lactobacillus acidophilus fermentation product can attenuate the acute phase response following a lipopolysaccharide challenge in weaned pigs

Lactobacillus acidophilus fermentation products have been used to improve the performance of nursery pigs. However, research on the influence of this supplement on health is lacking. This study was designed to determine if feeding a Lactobacillus acidophilus fermentation product to weaned pigs would reduce stress and acute phase responses (APR) following a lipopolysaccharide (LPS) challenge. Pigs (n=30; 6.4±0.1 kg) were individually housed in stainless steel pens with ad libitum access to feed and water. Pigs were weighed upon arrival, assigned to one of three groups (n=10/treatment), and fed for 18 days: (1) Control, fed a non-medicated starter diet; (2) Control diet with the inclusion of a Lactobacillus acidophilus fermentation product at 1 kg/metric ton (SGX1) and (3) Control diet with the inclusion of a Lactobacillus acidophilus fermentation product at 2 kg/metric ton (SGX2). On day 7 pigs were anesthetized for insertion of an i.p. temperature device, and similarly on day 14 for insertion of a jugular catheter. Pigs were challenged i.v. with LPS (25 µg/kg BW) on day 15. Blood samples were collected at 0.5 h (serum) and 1 h (complete blood cell counts) intervals from -2 to 8 h and at 24 h relative to LPS administration at 0 h. Pigs and feeders were weighed on days 7, 14 and 18. The supplemented pigs had increased BW and average daily gain before the challenge. In response to LPS, there was a greater increase in i.p. temperature in Control pigs compared with supplemented pigs. In addition, cortisol was reduced in SGX2 pigs while cortisol was elevated in SGX1 pigs at several time points post-challenge. White blood cells, neutrophils and lymphocytes were decreased in SGX1 and SGX2 compared with Control pigs. Furthermore, the pro-inflammatory cytokine response varied by treatment and dose of treatment. Specifically, serum TNF-α was greatest in SGX2, intermediate in Control, and least in SGX1 pigs, while the magnitude and temporal pattern of IFN-γ in SGX2 pigs was delayed and reduced. In contrast, IL-6 concentrations were reduced in both SGX treatment groups compared with Control pigs. These data demonstrate that different supplementation feed inclusion rates produced differential responses, and that feeding SynGenX to weaned pigs attenuated the APR to an LPS challenge.

Vitamin D/VDR, Probiotics, and Gastrointestinal Diseases

Vitamin D is an important factor in regulating inflammation, immune responses, and carcinoma inhibition via action of its receptor, vitamin D receptor (VDR). Recent studies have demonstrated the role of vitamin D/VDR in regulating host-bacterial interactions. Probiotics are beneficial bacteria with the power of supporting or favoring life on the host. In the current review, we will discuss the recent progress on the roles of vitamin D/VDR in gut microbiome and inflammation. We will summarize evidence of probiotics in modulating vitamin D/VDR and balancing gut microbiota in health and gastrointestinal diseases. Moreover, we will review the clinical application of probiotics in prevention and therapy of IBD or colon cancer. Despite of the gains, there remain several barriers to advocate broad use of probiotics in clinical therapy. We will also discuss the limits and future direction in scientific understanding of probiotics, vitamin D/VDR, and host responses.

Oral administration of Clostridium butyricum CGMCC0313-1 inhibits β-lactoglobulin-induced intestinal anaphylaxis in a mouse model of food allergy

Background

Probiotic bacteria can induce immune regulation or immune tolerance in patients with allergic diseases, but the underlying mechanisms are still unclear. There has been a growing interest in the use of beneficial bacteria for allergic diseases recently. This study aimed at exploring whether Clostridium butyricum CGMCC0313-1 (C. butyricum) can reduce β-lactoglobulin(BLG)-induced intestinal anaphylaxis in a murine model of food allergy.

Methods

The preventive and therapeutic effects of oral C. butyricum on anaphylactic symptoms induced via BLG in food allergy mice were investigated. Intestinal anaphylaxis, T helper (Th)-specific cytokines and transcription factors, secretory IgA (sIgA), CD4+ CD25+ Foxp3Treg cell and histopathological alterations were examined.

Results

Clostridium butyricum significantly ameliorated intestinal anaphylaxis symptoms in the food allergy mice. sIgA and CD4+ CD25+ Foxp3Treg cell were increased by oral C. butyricum. It also reversed the imbalance of Th1/Th2 andTh17/Treg.

Conclusions

Clostridium butyricum reduces BLG-induced intestinal anaphylaxis in mice and might be an additional or supplementary therapy for food allergy.

Milk: a postnatal imprinting system stabilizing FoxP3 expression and regulatory T cell differentiation

BACKGROUND

Breastfeeding has protective effects for the development of allergies and atopy. Recent evidence underlines that consumption of unboiled farm milk in early life is a key factor preventing the development of atopic diseases. Farm milk intake has been associated with increased demethylation of FOXP3 and increased numbers of regulatory T cells (Tregs). Thus, the questions arose which components of farm milk control the differentiation and function of Tregs, critical T cell subsets that promote tolerance induction and inhibit the development of allergy and autoimmunity.

FINDINGS

Based on translational research we identified at least six major signalling pathways that could explain milk's biological role controlling stable FoxP3 expression and Treg differentiation: (1) via maintaining appropriate magnitudes of Akt-mTORC1 signalling, (2) via transfer of milk fat-derived long-chain ω-3 fatty acids, (3) via transfer of milk-derived exosomal microRNAs that apparently decrease FOXP3 promoter methylation, (4) via transfer of exosomal transforming growth factor-β, which induces SMAD2/SMAD3-dependent FoxP3 expression, (5) via milk-derived Bifidobacterium and Lactobacillus species that induce interleukin-10 (IL-10)-mediated differentiation of Tregs, and (6) via milk-derived oligosaccharides that serve as selected nutrients for the growth of bifidobacteria in the intestine of the new born infant.

CONCLUSION

Accumulating evidence underlines that milk is a complex signalling and epigenetic imprinting network that promotes stable FoxP3 expression and long-lasting Treg differentiation, crucial postnatal events preventing atopic and autoimmune diseases.

Lactobacillus plantarum NCU116 Attenuates Cyclophosphamide-Induced Immunosuppression and Regulates Th17/Treg Cell Immune Responses in Mice

The balance of T helper cells 17 (Th17)/regulatory T cells (Treg) plays a key role in maintaining a normal immune response. It is well-known that cyclophosphamide (CTX) applied at high dose often damages the immune system by inhibiting immune cell proliferation. In this study, the immunomodulating effects of Lactobacillus plantarum NCU116 in CTX-induced immunosuppression mice were investigated. Results showed that the levels of cytokines interleukin (IL)-17 and IL-21 were significantly increased after 10 days of treatment with a high dose of NCU116 (46.92 ± 4.28 and 119.92 ± 10.89, respectively) compared with the model group (36.20 ± 2.63, 61.00 ± 6.92, respectively), and the levels of cytokines IL-23 and TGF-β3 of the three NCU116 treatment groups were significantly higher than that of the model group (90.48 ± 6.33 and 140.45 ± 14.30, respectively) (p < 0.05) and close to 62 and 69% of the normal group's level (140.98 ± 14.74 and 266.95 ± 23.11, respectively) at 10 days. The bacterium was also found to increase the expression levels of Th17 immune response and Treg immune response specific transcription factors RORγt and Foxp3. In addition, the bacterium significantly increased the number of CD4(+)T cells and dendrtic cells (DCs) and up-regulated mRNA expression of Toll-like receptors (TLRs). These findings demonstrated that NCU116 has the potential ability to enhance intestinal mucosa immunity and regulate the Th17/Treg balance, which may be attributed to the TLR pathway in DCs.