Probiotic Lactobacillus-induced improvement in murine chronic inflammatory bowel disease is associated with the down-regulation of pro-inflammatory cytokines in lamina propria mononuclear cells

Screening for Lactic Acid Bacterial Strains as Probiotics Exhibiting Anti-inflammatory and Antioxidative Characteristic Via Immune Modulation in HaCaT Cell

In this study, the basic probiotic characteristics and functional properties of lactic acid bacteria (LAB) were investigated using two in vitro models of inflammation induced by lipopolysaccharide (LPS) and H2O2. Fifteen strains were prescreened out of 60 LAB candidates based on their radical scavenging activity to determine the antioxidant capacity of the strains. The top 15 candidates were further investigated to evaluate their survival rate under low pH and bile salt conditions that mimic the intestinal environment. Three strains, Levilactobacillus brevis D70 (Levilact), Lactiplantibacillus pentosus S16 (Lactipla), and Limosilactobacillus fermentum MF10 (Limosilact), were capable of scavenging free radicals and survived under artificial intestinal conditions. Therefore, Levilact. brevis D70, Lactipla. pentosus S16, and Limosilact. fermentum MF10 were selected for further antioxidant, anti-inflammation, and mitochondrial activity examinations via cell models of inflammation and oxidative stress. Among the three strains, Limosilact. fermentum MF10 showed the highest anti-inflammatory activities by significantly downregulating the relative mRNA expression levels of inflammatory biomarkers such as interleukin 8 (IL-8) and interferon-gamma (IFN-γ) induced by LPS (P < 0.05). Moreover, Limosilact. fermentum MF10 was also capable of upregulating the gene expression levels of antioxidative mediator glutathione peroxidase 4 (GPX4) induced by reactive oxygen species (ROS) in both human HT-29 epithelial cells and human HaCaT keratinocytes. Limosilact. fermentum MF10 was also capable of regulating mitochondrial membrane potential (MMP), which plays a key role in the mitochondrial activity of HaCaT cells. As a result, Limosilact. fermentum MF10 showed the highest potential for probiotic properties and impacts the immune-related gut-skin axis by altering proinflammatory cytokines, antioxidative biomarkers, and MMP.

Exploring the Benefits of Probiotics in Gut Inflammation and Diarrhea-From an Antioxidant Perspective

Inflammatory bowel disease (IBD), characterized by an abnormal immune response, includes two distinct types: Crohn's disease (CD) and ulcerative colitis (UC). Extensive research has revealed that the pathogeny of IBD encompasses genetic factors, environmental factors, immune dysfunction, dysbiosis, and lifestyle choices. Furthermore, patients with IBD exhibit both local and systemic oxidative damage caused by the excessive presence of reactive oxygen species. This oxidative damage exacerbates immune response imbalances, intestinal mucosal damage, and dysbiosis in IBD patients. Meanwhile, the weaning period represents a crucial phase for pigs, during which they experience pronounced intestinal immune and inflammatory responses, leading to severe diarrhea and increased mortality rates. Pigs are highly similar to humans in terms of physiology and anatomy, making them a potential choice for simulating human IBD. Although the exact mechanism behind IBD and post-weaning diarrhea remains unclear, the oxidative damage, in its progression and pathogenesis, is well acknowledged. Besides conventional anti-inflammatory drugs, certain probiotics, particularly Lactobacillus and Bifidobacteria strains, have been found to possess antioxidant properties. These include the scavenging of reactive oxygen species, chelating metal ions to inhibit the Fenton reaction, and the regulation of host antioxidant enzymes. Consequently, numerous studies in the last two decades have committed to exploring the role of probiotics in alleviating IBD. Here, we sequentially discuss the oxidative damage in IBD and post-weaning diarrhea pathogenesis, the negative consequences of oxidative stress on IBD, the effectiveness of probiotics in IBD treatment, the application of probiotics in weaned piglets, and the potential antioxidant mechanisms of probiotics.

Lactobacillus rhamnosus reduces CD8+T cell mediated inflammation in patients with rheumatoid arthritis

BACKGROUND

The T cells, components of adaptive immunity participate in immune pathology of the autoimmune inflammatory disorder called rheumatoid arthritis (RA). The presence of TLRs on the surface of the CD8⁺ T cells and their ability to recognize bacterial moieties adds to the inflammatory burden in case of RA. It has been reported that the gut microbiome is necessary for the crucial shift in the balance between proinflammatory and anti-inflammatory cytokines. The altered gut microbiome and the presence of TLRs emphasizes on the microbiome driven inflammatory responses in case of RA.

METHODS

Eighty-nine RA patients participated in this study. Clinical variations like disease duration, number of actively inflamed joints, number and type of bone deformities, CRP, RF, Anti-CCP, ESR, DAS 28 score were recorded for each patient. Co-culture of CD8⁺T cells and bacteria has been performed with proper culture condition. TLRs and inflammatory mediators' expression level were checked by both qPCR and flow cytometry analysis.

RESULTS

We observed in the suppression of pro-inflammatory molecules like Granzyme B and IFNƳ and expression of TLR2 in CD8 + T cells upon treatment with Lactobacillus rhamnosus (L. rhamnosus). Moreover, L. rhamnosus activated CD8⁺T cells such that they could induce FOXP3 expression in CD4⁺T cells thereby skewing T cell population towards a regulatory phenotype. On the contrary, TLR4 engagement on CD8⁺T cell by Escherichia coli (E.coli) increased in inflammatory responses following ERK activation.

CONCLUSIONS

Thus, we conclude that L. rhamnosus can effectively suppress CD8⁺T cell mediated inflammation by a simultaneous decrease of Th1 cells that may potentiate better treatment modalities for RA.

Are heat-killed probiotics more effective than live ones on colon length shortness, disease activity index, and the histological score of an inflammatory bowel disease-induced murine model? A meta-analysis

This study was conducted to compare the efficiency of heat-killed and live probiotics against colon length shortness, disease activity index (DAI), and the histological score of an inflammatory bowel disease (IBD) via a meta-analysis. In February 2022, the eligible papers were collected from four databases (Google Scholar, PubMed, ScienceDirect, and Scopus). Using common- and random-effects models, the effect sizes were estimated throughout the standardized mean difference. Forty-three papers were recorded for our meta-analysis, and the heterogeneity of the effect sizes was determined with Cochran's Q test, followed by meta-ANOVA and meta-regression analyses. The probiotics (live and heat-killed) had globally an improving or preventive effect on colon length shortness, DAI, and histological score. The sub-group analysis revealed that the heat-killed probiotics had statistically (P > .05) the same improving effect on colon length shortness, DAI, and histological score as live probiotics. In conclusion, this study suggested that live and heat-killed probiotics had a similar impact on IBD symptoms investigated in this study. The present outcomes would be a good base for researchers willing to further compare the effects of live and heat-killed probiotics on IBD.

The Effect of Limosilactobacillus reuteri on Social Behavior Is Independent of the Adaptive Immune System

Gut microbes can modulate almost all aspects of host physiology throughout life. As a result, specific microbial interventions are attracting considerable attention as potential therapeutic strategies for treating a variety of conditions. Nonetheless, little is known about the mechanisms through which many of these microbes work. Recently, we and others have found that the commensal bacterium Limosilactobacillus reuteri (formerly Lactobacillus reuteri) reverses social deficits in several mouse models (genetic, environmental, and idiopathic) for neurodevelopmental disorders in a vagus nerve-, oxytocin-, and biopterin-dependent manner. Given that gut microbes can signal to the brain through the immune system and L. reuteri promotes wound healing via the adaptive immune response, we sought to determine whether the prosocial effect mediated by L. reuteri also depends on adaptive immunity. Here, we found that the effects of L. reuteri on social behavior and related changes in synaptic function are independent of the mature adaptive immune system. Interestingly, these findings indicate that the same microbe (L. reuteri) can affect different host phenotypes through distinct mechanisms. IMPORTANCE Because preclinical animal studies support the idea that gut microbes could represent novel therapeutics for brain disorders, it is essential to fully understand the mechanisms by which gut microbes affect their host's physiology. Previously, we discovered that treatment with Limosilactobacillus reuteri selectively improves social behavior in different mouse models for autism spectrum disorder through the vagus nerve, oxytocin reward signaling in the brain, and biopterin metabolites (BH4) in the gut. However, given that (i) the immune system remains a key pathway for host-microbe interactions and that (ii) L. reuteri has been shown to facilitate wound healing through the adaptive immune system, we examined here whether the prosocial effects of L. reuteri require immune signaling. Unexpectedly, we found that the mature adaptive immune system (i.e., conventional B and T cells) is not required for L. reuteri to reverse social deficits and related changes in synaptic function. Overall, these findings add new insight into the mechanism through which L. reuteri modulates brain function and behavior. More importantly, they highlight that a given bacterial species can modulate different phenotypes (e.g., wound healing versus social behavior) through separate mechanisms.

Microbial-Derived Tryptophan Catabolites, Kidney Disease and Gut Inflammation

Uremic metabolites, molecules either produced by the host or from the microbiota population existing in the gastrointestinal tract that gets excreted by the kidneys into urine, have significant effects on both health and disease. Tryptophan-derived catabolites are an important group of bacteria-produced metabolites with an extensive contribution to intestinal health and, eventually, chronic kidney disease (CKD) progression. The end-metabolite, indoxyl sulfate, is a key contributor to the exacerbation of CKD via the induction of an inflammatory state and oxidative stress affecting various organ systems. Contrastingly, other tryptophan catabolites positively contribute to maintaining intestinal homeostasis and preventing intestinal inflammation—activities signaled through nuclear receptors in particular—the aryl hydrocarbon receptor (AhR) and the pregnane X receptor (PXR). This review discusses the origins of these catabolites, their effect on organ systems, and how these can be manipulated therapeutically in the future as a strategy to treat CKD progression and gut inflammation management. Furthermore, the use of biotics (prebiotics, probiotics, synbiotics) as a means to increase the presence of beneficial short-chain fatty acids (SCFAs) to achieve intestinal homeostasis is discussed.

Structural determination of the cell wall polysaccharide LCPS-1 in Lacticaseibacillus paracasei strain Shirota YIT 9029

The neutral polysaccharides LCPS-1 and LCPS-2 play functional roles in the cell wall of the lactic acid bacterium Lacticaseibacillus paracasei strain Shirota YIT 9029 (LcS; formerly Lactobacillus casei strain Shirota YIT 9029), which has long been used as a probiotic food product. Studies have shown that LCPS-1 is associated with the immunomodulatory functions of LcS. We hypothesized that the structure of LCPS-1 is crucial for elucidating the mechanism of action of LcS on host immune responses and aimed to solve the undetermined primary structure of LCPS-1. Our results showed that LCPS-1 has a molecular weight of >400 kDa and is composed of Glc, Rha, Gal, and GlcNAc, with a repeating structure. Using limited degradation reactions, including controlled Smith and deamination degradations, we obtained key fragments with low molecular weight. Subsequently, their structures were analyzed using NMR spectra and other analytical techniques. Further, we integrated the results for each key fragment to derive the complete structure of LCPS-1. Our results indicated that the most probable structure of LCPS-1 is composed of two types of units (X, Y), each with a basic structure of seven sugars in which the C2-position of Rha is substituted with an acetyl group. The structure of X is {6[Glcβ1-2] Galα1-3[2-OAc] Rhaβ1-4Glcβ1-4[Rhaα1-3] [Glcα1-6] Glcβ1-} and that of Y is {6[Glcβ1-2] Galα1-3[2-OAc] Rhaβ1-4Glcβ1-4[Rhaα1-3] [Glcα1-6)] GlcNAcβ1-}, which can be expressed as (X₆Y₁₂)_n. In this study, we identified the primary structure of LCPS-1, and our results may enable an improved understanding of the immunomodulatory abilities of LcS.

Protective Effect of Levilactobacillus brevis Against Yersinia enterocolitica Infection in Mouse Model via Regulating MAPK and NF-κB Pathway

Although the use of the probiotic bacterium Lactobacillus for the treatment and prevention of diseases caused by various pathogenic bacteria has received increasing attention in recent years, its mechanism remains incompletely understood. Levilactobacillus brevis 23017 is a select probiotic strain that can regulate the immunity of host animals and resist pathogen infections. In this study, we analyzed the effect of L. brevis 23017 on Yersinia enterocolitica intestinal infection in a BALB/c mouse model and discussed its underlying mechanism. We found that in the mouse model, L. brevis 23017 prevented the damage of villi in the small intestine and decelerated weight loss after Y. enterocolitica infection. Moreover, we focused on the mechanism of the protective effect of L. brevis 23017 from the perspective of the damage and repair of the intestinal mucosal barrier. We observed that L. brevis 23017 maintained a normal mucosal barrier by altering the expression of tight junction proteins. Notably, our results indicated that L. brevis 23017 effectively promoted the secretion of the intestine-specific secretory immunoglobulin A (SIgA) by B cells via regulating cytokines and oxidative damage levels. This mechanism may be the reason for its protective role in Y. enterocolitica infection. In addition, our results demonstrated that the mechanism of L. brevis 23017 was related to antibacterial colonization and inflammation regulation and closely related to antioxidative stress and SIgA promotion. The protective effect of L. brevis 23017 on mice was related to the signaling pathway protein p38 MAPK and the phosphorylation levels of NF-κB. Our study provided novel insight into the mechanism of Lactobacillus against pathogenic bacterial infections. Such insight is of great importance for the prevention, diagnosis, and treatment of related diseases.

Advances in pathogenesis and therapeutic strategies for osteoporosis

Osteoporosis, is the most common bone disorder worldwide characterized by low bone mineral density, leaving affected bones vulnerable to fracture. Bone homeostasis depends on the precise balance between bone resorption by osteoclasts and bone matrix formation by mesenchymal lineage osteoblasts, and involves a series of complex and highly regulated steps. Bone homeostasis will be disrupted when the speed of bone resorption is faster than bone formation. Based on various regulatory mechanisms of bone homeostasis, a series of drugs targeting osteoporosis have emerged in clinical practice, including bisphosphonates, selective estrogen receptor modulators, calcitonin, molecular-targeted drugs and so on. However, many drugs have major adverse effects or are unsuitable for long-term use. Therefore, it is very urgent to find more effective therapeutic drugs based on the new pathogenesis of osteoporosis. In this review, we summarize novel mechanisms involved in the pathological process of osteoporosis, including the roles of gut microbiome, autophagy, iron balance and cellular senescence. Based on the above pathological mechanism, we found promising drugs for osteoporosis treatment, such as: probiotics, alpha-ketoglutarate, senolytics and hydrogen sulfide. This new finding may provide an important basis for elucidating the complex pathological mechanisms of osteoporosis and provide promising drugs for clinical osteoporosis treatment.

Probiotic supplementation attenuates age-related sarcopenia via the gut-muscle axis in SAMP8 mice

BACKGROUND

Age-related muscle dysfunctions are common disorders resulting in poor quality of life in the elderly. Probiotic supplementation is a potential strategy for preventing age-related sarcopenia as evidence suggests that probiotics can enhance muscle function via the gut-muscle axis. However, the effects and mechanisms of probiotics in age-related sarcopenia are currently unknown. In this study, we examined the effects of Lactobacillus casei Shirota (LcS), a probiotic previously reported to improve muscle function in young adult mice.

METHODS

We administered LcS (1 × 10⁸ or 1 × 10⁹  CFU/mouse/day) by oral gavage to senescence-accelerated mouse prone-8 mice for 12 weeks (16- to 28-week-old). Sixteen-week-old and 28-week-old SMAP8 mice were included as non-aged and aged controls, respectively. Muscle condition was evaluated using dual-energy X-ray absorptiometry for muscle mass, holding impulse and grip strength tests for muscle strength, and oxygen consumption rate, gene expressions of mitochondrial biogenesis, and mitochondrial number assays for mitochondria function. Inflammatory cytokines were determined using enzyme-linked immunosorbent assay. Gas chromatography-mass spectrometry was utilized to measure the short-chain fatty acid levels. The gut microbiota was analysed based on the data of 16S rRNA gene sequencing of mouse stool.

RESULTS

The LcS supplementation reduced age-related declines in muscle mass (>94.6%, P < 0.04), strength (>66% in holding impulse and >96.3% in grip strength, P < 0.05), and mitochondrial function (P < 0.05). The concentration of short-chain fatty acids (acetic, isobutyric, butyric, penic, and hexanoic acid) was recovered by LcS (>65.9% in the mice given high dose of LcS, P < 0.05) in the aged mice, and LcS attenuated age-related increases in inflammation (P < 0.05) and reactive oxygen species (>89.4%, P < 0.001). The high dose of LcS supplementation was also associated with distinct microbiota composition as indicated by the separation of groups in the beta-diversity analysis (P = 0.027). LcS supplementation altered predicted bacterial functions based on the gut microbiota. Apoptosis (P = 0.026), p53 signalling (P = 0.017), and non-homologous end-joining (P = 0.031) were significantly reduced, whereas DNA repair and recombination proteins (P = 0.043), RNA polymerase (P = 0.008), and aminoacyl-tRNA biosynthesis (P = 0.003) were increased. Finally, the genera enriched by high-dose LcS [linear discriminant analysis (LDA) score > 2.0] were positively correlated with healthy muscle and physiological condition (P < 0.05), while the genera enriched in aged control mice (LDA score > 2.0) were negatively associated with healthy muscle and physiological condition (P < 0.05).

CONCLUSIONS

Lactobacillus casei Shirota represents an active modulator that regulates the onset and progression of age-related muscle impairment potentially via the gut-muscle axis.

Probiotic Molecules That Inhibit Inflammatory Diseases

Consumption of probiotics for health purposes has increased vastly in the past few decades, and yet the scientific evidence to support health benefits from probiotics is only beginning to emerge. As more probiotics are studied, we are beginning to understand the mechanisms of action by which they benefit human health, as well as to identify the bacterial molecules responsible for these benefits. A new era of therapeutics is on the horizon in which purified molecules from probiotics will be used to prevent and treat diseases. In this review, we summarize the active molecules from probiotic bacteria that have been shown to affect innate and adaptive immunity and have health benefits in experimental settings. We focus particularly on the cellular and molecular mechanisms of the probiotic Bacillus subtilis and its active molecule, exopolysaccharide (ESPBs).

How Microbes Affect Depression: Underlying Mechanisms via the Gut-Brain Axis and the Modulating Role of Probiotics

Accumulating evidence suggests that the gut microbiome influences the brain functions and psychological state of its host via the gut-brain axis, and gut dysbiosis has been linked to several mental illnesses, including major depressive disorder (MDD). Animal experiments have shown that a depletion of the gut microbiota leads to behavioral changes, and is associated with pathological changes, including abnormal stress response and impaired adult neurogenesis. Short-chain fatty acids such as butyrate are known to contribute to the up-regulation of brain-derived neurotrophic factor (BDNF), and gut dysbiosis causes decreased levels of BDNF, which could affect neuronal development and synaptic plasticity. Increased gut permeability causes an influx of gut microbial components such as lipopolysaccharides, and the resultant systemic inflammation may lead to neuroinflammation in the central nervous system. In light of the fact that gut microbial factors contribute to the initiation and exacerbation of depressive symptoms, this review summarizes the current understanding of the molecular mechanisms involved in MDD onset, and discusses the therapeutic potential of probiotics, including butyrate-producing bacteria, which can mediate the microbiota-gut-brain axis.

Lactobacillus plantarum FNCC 0137 fermented red Moringa oleifera exhibits protective effects in mice challenged with Salmonella typhi via TLR3/TLR4 inhibition and down-regulation of proinflammatory cytokines

Background

Salmonella typhi is a foodborne pathogenic bacterium that threatens health. S. typhi infection exacerbated the antibiotic resistance problem that needs alternative strategies. Moringa oleifera possesses anti-inflammatory and antimicrobial effects. However, there is a lack of information about the pharmacological value of red M. oleifera. The fermentation of red M. oleifera leaves extract (RMOL) is expected to add to its nutritional value.

Objective

The present study aimed to evaluate non-fermented RMOL (NRMOL) and fermented RMOL (FRMOL) effects on S. typhi infection in mice.

Materials and methods

Female Balb/C mice were randomly divided into eight groups. The treatment groups were orally administered with NRMOL or FRMOL at doses 14, 42, and 84 mg/kg BW during the 28 days experimental period. Then S. typhi was introduced to mice through intraperitoneal injection except in the healthy groups. The NRMOL or FRMOL administration was continued for the next seven days. Cells that expressed CD11b⁺ TLR3⁺, CD11b⁺TLR4⁺, CD11b⁺IL-6⁺, CD11b⁺IL-17⁺, CD11b⁺TNF-a⁺, and CD4⁺CD25⁺CD62L⁺ were assessed by flow cytometry.

Results

Our result suggested that NRMOL and FRMOL extracts significantly reduced (p < 0.05) the expression of CD11b⁺TLR3⁺, CD11b⁺TLR4⁺, CD11b⁺IL-6⁺, CD11b⁺IL-17⁺, and CD11b⁺TNF-α⁺ subsets. In contrast, NRMOL and FRMOL extracts significantly increased (p < 0.05) the expression of CD4⁺CD25⁺CD62L⁺ subsets. NRMOL at dose 14 and 42 mg/kg BW was more effective compared to FRMOL in reducing the expression of CD11b⁺TLR3⁺, CD11b⁺TLR4⁺, and CD11b⁺TNF-α⁺ subsets.

Conclusion

Our findings demonstrated that NRMOL and FRMOL extracts could be promising agents for protection against S. typhi infection via modulation of TLR3/TLR4, regulatory T cells, and proinflammatory cytokines.

Autochthonous Probiotics Alleviate the Adverse Effects of Dietary Histamine in Juvenile Grouper (Epinephelus coioides)

High dose (0.3%) of dietary histamine can cause adverse effects on growth performance, innate immunity, and gut health in juvenile grouper (Epinephelus coioides). In the present study, three autochthonous probiotics (Bacillus pumilus SE5, Psychrobacter sp. SE6, and Bacillus clausii DE5) were supplemented separately to diets containing 0.3% of histamine and their effects on growth performance, innate immunity, and gut health of grouper (E. coioides) were evaluated in a 56-day feeding trial. The results showed considerable increase in weight gain, specific growth rate, hepatosomatic index, and decreased feed conversion rate in groupers fed with probiotic-supplemented diets. Supplementation of autochthonous probiotics has improved antioxidant capacity and innate immunity of E. coioides by measuring correlative parameters, such as total antioxidant capacity, superoxide dismutase activity, malondialdehyde content, and so on. Additionally, dietary probiotics have significantly reduced the levels of serum interleukin-1β (at days 28 and 56), fatty acid-binding protein 2, and intestinal trefoil factor (at day 28), and promoted intestinal integrity following remarkably increased muscle thickness and mucosal fold height at day 56, especially in grouper fed with B. pumilus SE5 containing diet (P < 0.05). On day 56, the gut microbial composition of E. coioides was positively shaped by autochthonous probiotics, the relative abundance of potentially pathogenic Photobacterium decreased while beneficial Lactobacillus increased in fish fed with probiotic strains, especially with B. pumilus SE5 and B. clausii DE5. These results suggest that among the three autochthonous probiotic strains tested, B. pumilus SE5 is showing better efficiency in alleviating the adverse effects of (high levels) dietary histamine by decreasing the expression of inflammatory markers and by improving the growth, innate immunity, and gut health of juvenile grouper E. coioides.

Insight Into the Beneficial Role of Lactiplantibacillus plantarum Supernatant Against Bacterial Infections, Oxidative Stress, and Wound Healing in A549 Cells and BALB/c Mice

Lactiplantibacillus plantarum MTCC 2621 is a well-characterized probiotic strain and is reported to possess many health benefits. However, the wound healing potential of this probiotic is yet to be explored. Here, we have assessed the antibacterial, antioxidant, and wound healing activities of cell-free supernatant of Lactiplantibacillus plantarum MTCC 2621 (Lp2621). Lp2621 exhibited excellent antibacterial activity against the indicator bacteria in the agar well diffusion assay. Lp2621 did not show any hemolytic activity. The safety of Lp2621 gel was established using the skin irritation assay in BALB/c mice, and no dermal reactions were observed. The supernatant showed 60–100% protection of A549 cells against H₂O₂-induced stress. In the scratch assay, Lp2621 accelerated wound healing after 24 h of treatment. The percent wound healing was significantly higher in cells treated with Lp2621 at 18–24 h posttreatment. In an excision wound healing in mice, topical application of Lp2621 gel showed faster healing than the vehicle- and betadine-treated groups. Similar wound healing activity was observed in wounds infected with Staphylococcus aureus. Histological examination revealed better wound healing in Lp2621-treated mice. Topical treatment of the wounds with Lp2621 gel resulted in the upregulation of pro-inflammatory cytokine IL-6 in the early phase of wound healing and enhanced IL-10 expression in the later phase. These findings unveil a protective role of Lp2621 against bacterial infection, oxidative stress, and wound healing.

The probiotic supplementation role in improving the immune system among people with ulcerative colitis: a narrative review

OBJECTIVES

The purpose of this paper is to summarize the current evidence on probiotics' uses as an adjuvant for ulcerative colitis (UC) and provide an understanding of the effect of probiotics supplement on the immune system and inflammatory responses among UC patients and subsequent therapeutic benefits.

CONTENT

A narrative review of all the relevant published papers known to the author was conducted.

SUMMARY

UC is a chronic inflammatory bowel disease (IBD) that results in inflammation and ulceration of the colon and rectum. The primary symptoms of active disease are diarrhea, abdominal pain, and rectal bleeding. About 70% of the human immune system (mucosal-associated lymphoid tissue) originates in the intestine. Probiotics are live microorganisms that help in stabilizing the gut microbiota (nonimmunologic gut defense), restores normal flora, and enhance the humoral immune system. Probiotics especially Bifidobacterium, Saccharomyces boulardii, and lactic acid-producing bacteria have been used as an adjunct therapy for treating UC to ameliorate disease-related symptoms and reduce relapse rate. Probiotics, in general, modulate the immune system through their ability to enhance the mucosal barrier function, or through their interaction with the local immune system to enhance regulatory T cell responses, decrease the pro-inflammatory cytokines such as tumor necrosis factor alpha and interleukin 1 beta and increase anti-inflammatory factor interleukin 10.

OUTLOOK

More studies are needed to explore the properties of the various probiotic bacterial strains, their different uses, as well as the dosage of probiotics and duration for treating different disorders. Further clinical investigations on mechanisms of action and how probiotics modulate the immune system may lead to further advances in managing IBD.

The probiotic supplementation role in improving the immune system among people with ulcerative colitis: a narrative review

OBJECTIVES

The purpose of this paper is to summarize the current evidence on probiotics' uses as an adjuvant for ulcerative colitis (UC) and provide an understanding of the effect of probiotics supplement on the immune system and inflammatory responses among UC patients and subsequent therapeutic benefits.

CONTENT

A narrative review of all the relevant published papers known to the author was conducted.

SUMMARY

UC is a chronic inflammatory bowel disease (IBD) that results in inflammation and ulceration of the colon and rectum. The primary symptoms of active disease are diarrhea, abdominal pain, and rectal bleeding. About 70% of the human immune system (mucosal-associated lymphoid tissue) originates in the intestine. Probiotics are live microorganisms that help in stabilizing the gut microbiota (nonimmunologic gut defense), restores normal flora, and enhance the humoral immune system. Probiotics especially Bifidobacterium, Saccharomyces boulardii, and lactic acid-producing bacteria have been used as an adjunct therapy for treating UC to ameliorate disease-related symptoms and reduce relapse rate. Probiotics, in general, modulate the immune system through their ability to enhance the mucosal barrier function, or through their interaction with the local immune system to enhance regulatory T cell responses, decrease the pro-inflammatory cytokines such as tumor necrosis factor alpha and interleukin 1 beta and increase anti-inflammatory factor interleukin 10.

OUTLOOK

More studies are needed to explore the properties of the various probiotic bacterial strains, their different uses, as well as the dosage of probiotics and duration for treating different disorders. Further clinical investigations on mechanisms of action and how probiotics modulate the immune system may lead to further advances in managing IBD.

Anti-inflammatory and Anti-osteoporotic Potential of Lactobacillus plantarum A41 and L. fermentum SRK414 as Probiotics

This study involves an investigation on the probiotic properties of lactic acid bacteria and their potential applications in an in vitro model of lipopolysaccharide (LPS)-stimulated inflammation and dexamethasone-induced osteoporosis. Nine strains were pre-screened from 485 lactic acid bacteria based on their survival at a low pH and in a solution containing bile salts. All candidates were capable of surviving in an environment with low pH and with bile salts and could successfully colonize the intestine. Furthermore, their functional properties, such as anti-oxidation and anti-inflammation, were evaluated. Of the nine probiotic candidates, Lactobacillus plantarum A41 and L. fermentum SRK414 exhibited the highest anti-oxidative capacity. Moreover, only L. plantarum A41 and L. fermentum SRK414 could increase gut barrier function by upregulating the mRNA expression of tight junction proteins and inhibit the expression of inflammatory mediators induced by LPS-stimulated inflammation. Interestingly, these two strains were also capable of regulating several bone metabolism-related markers playing a role in bone homeostasis and osteoblast differentiation. In brief, L. plantarum A41 and L. fermentum SRK414 exhibited high probiotic potential and potentially impact immune-related bone health by modulating pro-inflammatory cytokines and bone metabolism-related markers.

Lactobacillus-Based Probiotics Reduce the Adverse Effects of Stress in Rodents: A Meta-analysis

Lactobacillus species play a critical role in the bidirectional communication between the gut and the brain. Consequently, they have the potential to aid in the treatment of psychological disorders. The impact of Lactobacillus supplementation on the stress responses triggering psychological disorders has not been systematically reviewed. Therefore, the aim of this meta-analysis is to summarize the body of research assessing the effects of Lactobacillus-based probiotics in rodents that underwent an experimental stress treatment or not. The duration of immobility in a Forced Swim Test (FST) was the outcome used to measure changes induced by various treatments. Four online databases were systematically searched for relevant studies published in English. Fourteen studies meeting the criteria were included in the meta-analysis. The effects of probiotic supplementation and stress treatment on the duration of immobility in the FST were analyzed using a generalized linear mixed model. Publication bias was evaluated by funnel plots. Our analysis shows that Lactobacillus-based probiotic supplements significantly reduce immobility in the FST (P < 0.001) in stressed rodents. However, probiotics did not affect the rodents that did not undergo the stress treatment (P = 0.168). These findings provide a better understanding of the potential of Lactobacillus-based probiotics for the management of stress-induced behavior.

Probiotic and Functional Properties of Limosilactobacillus reuteri INIA P572

Limosilactobacillus reuteri INIA P572 is a strain able to produce the antimicrobial compound reuterin in dairy products, exhibiting a protective effect against some food-borne pathogens. In this study, we investigated some probiotic properties of this strain such as resistance to gastrointestinal passage or to colonic conditions, reuterin production in a colonic environment, and immunomodulatory activity, using different in vitro and in vivo models. The results showed a high resistance of this strain to gastrointestinal conditions, as well as capacity to grow and produce reuterin in a human colonic model. Although the in vitro assays using the RAW 264.7 macrophage cell line did not demonstrate direct immunomodulatory properties, the in vivo assays using a Dextran Sulphate Sodium (DSS)-induced colitic mice model showed clear immunomodulatory and protective effects of this strain.

Oral administration of Moringa oleifera leaf powder relieves oxidative stress, modulates mucosal immune response and cecal microbiota after exposure to heat stress in New Zealand White rabbits

Background

Heat stress (HS) disrupts the gut barrier allowing the uptake of lipopolysaccharide (LPS) and leads to an inflammatory response and changes in gut microbiota composition. Moringa oleifera leaf powder (MOLP) has been proposed to combat HS, yet its alleviate role is currently under investigation. The current study investigated the effects of chronic HS and MOLP supplementation on changes in redox status and immune response of cecal mucosa along with alteration in cecal microbiota.

Methods

A total of 21 young New Zealand White (NZW) rabbits (male) about 32 weeks old (mean body weight of 3318 ± 171 g) reared on a commercial pelleted diet were employed; divided into three groups (n = 7): control (CON, 25 °C), heat stress (HS, 35 °C for 7 h daily), and HS supplemented orally with MOLP (HSM, 35 °C) at 200 mg/kg body weight per day for 4 weeks.

Results

The results demonstrated that MOLP supplementation increased organ index of cecal tissue compared with the HS group (P > 0.05). Levels of malonaldehyde (MDA) and activity of superoxide dismutase (SOD) as well as lactate dehydrogenase (LDH) were reduced in the cecal mucosa of the HSM group compared with the HS group. MOLP downregulated the contents of cecal mucosa LPS, several inflammatory markers (TNF-α/IL-1α/IL-1β), and myeloperoxidase (MPO) in the HSM group (P < 0.05). Secretory immunoglobulin A (SIgA) was increased in the HSM group compared with the HS group (P < 0.05). The transcriptome of cecal mucosa showed that MOLP reduced gene expression relative to several immune factors, including IL-10, IFNG, and RLA, whereas both HS and MOLP increased the gene expression of fat digestion and absorption pathway, including APOA1, FABP1, FABP2, MTTP, and LOC100344166, compared to the CON group (P < 0.001). At the phylum level, the relative abundance of Proteobacteria was increased by HS, while Actinobacteria was significantly increased by HSM compared to other groups (P < 0.05). At genus level, Papillibacter was higher in abundance in HSM groups compared to CON and HS groups (P < 0.05). Higher butyrate concentrations were observed in the HSM group than HS and CON groups (P < 0.05).

Conclusion

In conclusion, HS in growing rabbits resulted in alteration of cecal microbiota at phyla level as well as increased oxidative stress and expression of mucosal inflammatory genes. Whereas, oral MOLP supplementation elevated the relative weight of cecum, affected their immunological and cecal micro-ecosystem function by improving antioxidant status and down-regulating mucosal tissue inflammatory response.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40104-021-00586-y.

Protective effects of a novel Lactobacillus rhamnosus strain with probiotic characteristics against lipopolysaccharide-induced intestinal inflammation in vitro and in vivo

Lipopolysaccharides (LPS), a main component of the Gram-negative bacterial cell wall, can damage the epithelial wall barrier and induce chronic intestinal inflammation. The purpose of this study is to evaluate whether the novel L. rhamnosus could alleviate intestinal inflammation and damage induced by LPS and explore the possible underlying molecular mechanism. L. rhamnosus JL-1 was selected from five L. rhamnosus strains due to its strong adherence capacity to Caco-2 cells (92.89%) and it could survive in simulated gastrointestinal juices. Whole genome sequencing analysis showed that there were no translocation and inversion regions in the genome of L. rhamnosus JL-1 compared with L. rhamnosus GG. Comparative genomic analysis showed that there were encoding genes related to adhesion, acid resistance and bile salt resistance in the genome of L. rhamnosus JL-1. Both in vitro and in vivo experiments indicated that LPS challenge inhibited the mRNA and protein expression of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6). However, the mRNA and protein expressions of pro-inflammatory cytokines were inhibited by pre-treatment with L. rhamnosus JL-1 in a dose-dependent manner. The result of histopathology analysis of ileum showed that oral administration of L. rhamnosus JL-1 reduced pathological damage induced by LPS. Furthermore, it was revealed that L. rhamnosus JL-1 could inhibit the mRNA and protein expressions of TLR4 and NF-κB. These results strongly suggested that L. rhamnosus JL-1 relieved LPS-induced intestinal inflammation by inhibiting the TLR4/NF-κB signaling pathway. To sum up, L. rhamnosus JL-1 has a potential probiotic function and plays an important role in preventing LPS-induced intestinal inflammation and damage.

Probiotics Lactobacillus rhamnosus GG ATCC53103 and Lactobacillus plantarum JL01 induce cytokine alterations by the production of TCDA, DHA, and succinic and palmitic acids, and enhance immunity of weaned piglets

Probiotics, including Lactobacillus rhamnosus GG ATCC53103 and Lactobacillus plantarum JL01, can improve growth performance and immunity of piglets, and relieve weaning stress-related immune disorders such as intestinal infections and inflammation. This study aimed to evaluate the ability of co-administration of the probiotics L. rhamnosus GG ATCC53103 and L. plantarum JL01 to stimulate immune responses and improve gut health during the critical weaning period in piglets. Forty-eight weaned piglets were randomly divided into four groups, and fed daily for 28 days either without, or with the two probiotics independently, or in combination. On day 28, we analyzed the cytokine and bacterial changes in intestinal mucosa and the hepatic portal vein blood metabolites of the weaned piglets. Our results showed that combined L. rhamnosus GG ATCC53103 and L. plantarum JL01 significantly increased (p < 0.05) the growth performance and expression of IL-10 and TGF-β1 mRNAs. In contrast, this treatment significantly decreased (p < 0.05) IL-1β mRNA level in the jejunum, ileum, and cecum. Furthermore, the secretion of IL-6 in the cecum, IL-1β in the jejunum, ileum, and cecum, and TNF-α in the jejunum and ileum was significantly decreased (p < 0.05). The relative abundance of Prevotella_9 and Enterococcus in ileum and cecum was significantly increased (p < 0.05). The relative abundance of Ruminococcus_1 and Ruminococcaceae_UCG-005 in cecum was significantly decreased (p < 0.05). Prevotella_9 and Enterococcus may increase the accumulation of (4Z,7Z,10Z,13Z,16Z,19Z)-4,7,10,13,16,19-docosahexaenoic acid (DHA) and tauroursodeoxycholic acid (TCDA) in portal vein blood, while Ruminococcus_1 and Ruminococcaceae_UCG-005 may decrease the accumulation of succinic and palmitic acids. These results indicate that L. rhamnosus GG ATCC53103 and L. plantarum JL01 may regulate cytokine levels by reducing the accumulation of succinic and palmitic acids and increasing the accumulation of TCDA and DHA, thereby enhancing the immunity of weaned piglets.

Immune System Efficiency in Cancer and the Microbiota Influence

The immune system plays a critical role in preventing cancer development and progression. However, the complex network of cells and soluble factor that form the tumor microenvironment (TME) can dictate the differentiation of tumor-infiltrating leukocytes and shift the antitumor immune response into promoting tumor growth. With the advent of cancer immunotherapy, there has been a reinvigorated interest in defining how the TME shapes the antitumor immune response. This interest brought to light the microbiome as a novel player in shaping cancer immunosurveillance. Indeed, accumulating evidence now suggests that the microbiome may confer susceptibility or resistance to certain cancers and may influence response to therapeutics, particularly immune checkpoint inhibitors. As we move forward into the age of precision medicine, it is vital that we define the factors that influence the interplay between the triad immune system-microbiota-cancer. This knowledge will contribute to improve the therapeutic response to current approaches and will unravel novel targets for immunotherapy.

Feline comorbidities: What do we really know about feline triaditis?

PRACTICAL RELEVANCE

Feline triaditis describes concurrent pancreatitis, cholangitis and inflammatory bowel disease (IBD). The reported prevalence is 17-39% in ill referral patients. While the aetiology is poorly understood, it is known to include infectious, autoimmune and physical components. What is not known is whether different organs are affected by different diseases, or the same process; indeed, triaditis may be part of a multiorgan inflammatory disease. Feline gastrointestinal tract anatomy plays its role too. Specifically, the short small intestine, high bacterial load and anatomic feature whereby the pancreatic duct joins the common bile duct before entering the duodenal papilla all increase the risk of bacterial reflux and parenchymal inflammation. Inflammation may also be a sequela of bowel bacterial translocation and systemic bacteraemia.

DIAGNOSTIC CHALLENGES

Cholangitis, pancreatitis and IBD manifest with overlapping, vague and non-specific clinical signs. Cholangitis may be accompanied by increased serum liver enzymes, total bilirubin and bile acid concentrations, and variable ultrasonographic changes. A presumptive diagnosis of pancreatitis is based on increased serum pancreatic lipase immunoreactivity or feline pancreas-specific lipase, and/or abnormal pancreatic changes on ultrasonography, though these tests have low sensitivity. Diagnosis of IBD is challenging without histopathology; ultrasound findings vary from normal to mucosal thickening or loss of layering. Triaditis may cause decreased serum folate or cobalamin (B12) concentrations due to intestinal disease and/or pancreatitis. Triaditis can only be confirmed with histopathology; hence, it remains a presumptive diagnosis in most cases.

EVIDENCE BASE

The literature on feline triaditis, pancreatitis, cholangitis and IBD is reviewed, focusing on histopathology, clinical significance and diagnostic challenges. Current management recommendations are provided. Further studies are needed to understand the complex pathophysiology, and in turn improve diagnosis and treatment.

Probiotics: A Dietary Factor to Modulate the Gut Microbiome, Host Immune System, and Gut-Brain Interaction

Various benefits of probiotics to the host have been shown in numerous human clinical trials. These organisms have been proposed to act by improving the balance of the gut microbiota and enhancing the production of short-chain fatty acids, as well as by interacting with host cells in the gastrointestinal tract, including immune cells, nerve cells, and endocrine cells. Although the stimulation of host cells by probiotics and subsequent signaling have been explained by in vitro experiments and animal studies, there has been some skepticism as to whether probiotics can actually interact with host cells in the human gastrointestinal tract, where miscellaneous indigenous bacteria coexist. Most recently, it has been shown that the ileal microbiota in humans after consumption of a fermented milk is occupied by probiotics for several hours, indicating that there is adequate opportunity for the ingested strain to stimulate the host cells continuously over a period of time. As the dynamics of ingested probiotics in the human gastrointestinal tract become clearer, further progress in this research area is expected to elucidate their behavior within the tract, as well as the mechanism of their physiological effects on the host.

Interactions Between Food and Gut Microbiota: Impact on Human Health

Understanding the relationship between food and the gut microbiota, their interactions, and how each modulates the other is critical for successful promotion of human health. This review seeks to summarize ( a) the current knowledge on the effects of food and food components on gut microbiota and ( b) the association between gut microbiota, consumption of food, and food bioactive components and the resulting beneficial health outcomes. Our goal is to provide state-of-the-art information on food and gut microbiota interactions and to stimulate discussions and research approaches that will move the field forward.

The effect of selected Lactobacillus strains on dextran sulfate sodium-induced mouse colitis model

Inflammatory bowel disease (IBD) comprises two major illnesses: Crohn's disease (CD) and ulcerative colitis (UC). Dextran sulfate sodium (DSS) mouse colitis model has been used in understanding the mechanism of IBD. This study was conducted to examine selected Lactobacillus spp. as potential IBD treatment in the DSS-induced animal model. Balb/c mice were used and colitis was induced by adding 5% dextran sodium sulfate into the drinking water for 8 days. Colon length, disease activity index (DAI) and histological analysis were measured as markers of inflammation in DSS colitis mice. The majority of the Lactobacillus species significantly prevented the shortening of the colon length compared with the DSS group. The DAI scores of mice were significantly reduced following usage of four Lactobacillus strains included: Lactobacillus plantarum 03 and 06, Lactobacillus brevis 02 and Lactobacillus rhamnosus 01. The histological analysis exhibited that oral administration of Lactobacillus strains had therapeutic effects on mice colitis. L. plantarum and L. brevis showed better therapeutic effect against DSS-induced acute colitis mice. The probiotic activities of these three isolates indicated that the probiotic effects were strain specific and none of these useful bacteria could exhibit all of the valued probiotic properties simultaneously.

Surface Modifications for Improved Delivery and Function of Therapeutic Bacteria

Live therapeutic bacteria (LTBs) hold promise to treat microbiome-related diseases. However, few approaches to improve the colonization of LTBs in the gastrointestinal tract exist, despite colonization being a prerequisite for efficacy of many LTBs. Here, a modular platform to rapidly modify the surface of LTBs to enable receptor-specific interactions with target surfaces is reported. Inspired by bacterial adhesins that facilitate colonization, synthetic adhesins (SAs) are developed for LTBs in the form of antibodies conjugated to their surface. The SA platform is nontoxic, does not alter LTB growth kinetics, and can be used with any antibody or bacterial strain combination. By improving adhesion, SA-modified bacteria demonstrate enhanced in vitro pathogen exclusion from cell monolayers. In vivo kinetics of SA-modified LTBs is tracked in the feces and intestines of treated mice, demonstrating that SA-modified bacteria alter short-term intestinal transit and improve LTB colonization and pharmacokinetics. This platform enables rapid formation of an intestinal niche, leading to an increased maximum concentration and a 20% improvement in total LTB exposure. This work is the first application of traditional pharmacokinetic analysis to design and evaluate LTB drug delivery systems and provides a platform toward controlling adhesion, colonization, and efficacy of LTBs.

A review on the consumption of vended fruits: microbial assessment, risk, and its control

Fruits are very beneficial to health and their consumption has been recommended in daily diets. However, when fresh fruits are harvested and processed into sliced ready-to-eat or vended forms for sale, hygienic procedures are neglected. Thus, they are easily infested by pathogens. In addition, uneducated vendors who sell these fruits often display or hawk them on the streets in contaminated containers, utensils, or dirty environments. This poses a great threat to the health of consumers. In the light of this realization, some microbial assessments have been carried out to ascertain the safety of these vended fruits, thus making it a necessity to exploit the outcomes of some of these microbial assessments on vended fruits in order to sensitize the consumers on the effect of their consumption and mitigate risk by improving their quality. This will assist to lower certain health concerns, an outbreak of diseases, and death.

Lactobacillus paracasei PS23 decelerated age-related muscle loss by ensuring mitochondrial function in SAMP8 mice

Sarcopenia is a common impairment in the elderly population responsible for poor outcomes later in life; it can be caused by age-related alternations. Only a few strategies have been reported to reduce sarcopenia. Lactobacillus paracasei PS23 (LPPS23) has been reported to delay some age-related disorders. Therefore, here we investigated whether LPPS23 decelerates age-related muscle loss and its underlying mechanism. Female senescence-accelerated mouse prone-8 (SAMP8) mice were divided into three groups (n=6 each): non-aging (16-week-old), control (28-week-old), and PS23 (28-week-old) groups. The control and PS23 groups were given saline and LPPS23, respectively. We evaluated the effects of LPPS23 by analyzing body weight and composition, muscle strength, protein uptake, mitochondrial function, reactive oxygen species (ROS), antioxidant enzymes, and inflammation-related cytokines. LPPS23 significantly attenuated age-related decreases of muscle mass and strength. Compared to the control group, the non-aging and PS23 groups exhibited higher mitochondrial function, IL10, antioxidant enzymes, and protein uptake. Moreover, inflammatory cytokines and ROS were lower in the non-aging and PS23 groups than the control group. Taken together, LPPS23 extenuated sarcopenia progression during aging; this effect might have been enacted by preserving the mitochondrial function via reducing age-related inflammation and ROS and by retaining protein uptake in the SAMP8 mice.

Probiotics and bone disorders: the role of RANKL/RANK/OPG pathway

The skeleton is the framework and in charge of body configuration preservation. As a living tissue, bones are constantly being formed and absorbed. Osteoblasts and osteoclasts are the main bone cells and balance between their activities indicates bone health. Several mechanisms influence the bone turnover and RANKL/RANK/OPG pathway is one of them. This system, whose components are part of the tumor necrosis factor (TNF) superfamily, exists in many organs and could play a role in bone modeling and remodeling. RANKL/RANK pathway controls osteoclasts activity and formation. In addition, they are identified as key factors on bone turnover in different pathological situations. At the same time, OPG (RANKL's decoy receptor) plays role as a bone-protective factor by binding to RANKL and prevention of extra resorption. The lack of balance between RANKL and OPG could result in excessive bone resorption. Probiotics, the beneficial microorganisms for human health, entail bones in their advantages. Recent studies suggest that probiotics could reduce inflammatory factors (for example TNF-α and IL-1β) and increase bone OPG expression. In addition, probiotics have shown to maintain bones in various ways. Although current evidence is not enough for definitive approval of probiotics' efficacy on RANKL/RANK/OPG, its positive responses from conducted studies are significant. Understanding of the probiotics' effects on RANKL/RANK/OPG pathway will help focus future studies, and assist in developing efficient treatment strategies.

Lactobacillus casei LH23 modulates the immune response and ameliorates DSS-induced colitis via suppressing JNK/p-38 signal pathways and enhancing histone H3K9 acetylation

Probiotics are thought to have immunomodulatory functions, improve inflammatory disorders and treat inflammatory bowel disease (IBD).

Effect of a bioactive product SEL001 from Lactobacillus sakei probio65 on gut microbiota and its anti-colitis effects in a TNBS-induced colitis mouse model

This study underpins the therapeutic potential of SEL001, a bioactive product isolated from Lactobacillus sakei probio65, in terms of its anti-inflammatory properties and its effect on gut-microbiota in a TNBS-induced ulcerative colitis mouse model. Ulcerative colitis was developed in mice by intra rectal administration of trinitrobenzene sulfonic acid. Bioactive product SEL001 (50 mg/kg b.w.) was administered orally. Myeloperoxidase activity was measured using 3,3', 5,5'-tetramethylbenzidine. The entire colon was sampled for post-mortem clinical assessment. Colonic injury was assessed through histological and histomorphometric examinations. The 454 pyrosequencing and QIIME pipeline were used for gut microbiota analysis and statistical analysis were conducted using R. mRNA extraction from colon tissue and RT-PCR approaches were employed to determine the changes in the level of specific biomarker genes associated with UC. The results depict that SEL001 significantly lowered pro-inflammatory cytokines, including CD4, TNF-α, and interleukin-6. Examination of clinical and histopathological traits revealed that SEL001 was effective and potent in reducing the inflammatory signatures of UC to a similar extent as did by the standard drug mesalamine (5-ASA). Pyro-sequencing 16S data revealed that the reduction in the major member of phylum Firmicutes, which has been previously associated with a higher risk of UC. The SEL001, an anti-inflammatory bioactive product originated from a probiotic strain L. sakei probio65 could be an alternative therapeutic agent for treatment of UC.

Potential Evaluation and Health Fostering Intrinsic Traits of Novel Probiotic Strain Enterococcus durans F3 Isolated from the Gut of Fresh Water Fish Catla catla

Over the last few years, marine environment was found to be a source of surplus natural products and microorganisms with new bioactive secondary metabolites of interest which can divulge nutritional and biological impact on the host. This study aims to assess the possible, inherent and functional probiotic properties of a novel probiotic strain Enterococcus durans F3 (E. durans F3) isolated from the gut of fresh water fish Catla catla. Parameters for evaluating and describing the probiotics described in FAD/WHO guidelines were followed. E. durans F3 demonstrated affirmative results including simulated bile, acid and gastric juice tolerance with exhibited significant bactericidal effect against pathogens Staphylococcus aureus, Salmonella Typhi, Escherichia coli and Pseudomonas aeruginosa. This can be due to the enterocin produced by E. durans F3 strain, which was resolute by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) gel with amplification of the anticipated fragment of a structural gene; enterocin A, followed by antibiotic susceptibility assessment. Effective antioxidant potentiality against α-diphenyl-α-picrylhydrazyl free radicals including lipase, bile salt hydrolase activity with auto-aggregation and cell surface hydrophobicity was similarly observed. Results are proving the potentiality of E. durans F3, which can also be used as probiotic starter culture in dairy industries for manufacturing new products that imparts health benefits to the host. Finding the potent and novel probiotic strains will also satisfy the current developing market demand for probiotics.

Milk Fermented with Lactobacillus fermentum Ameliorates Indomethacin-Induced Intestinal Inflammation: An Exploratory Study

The aim of this study was to evaluate the effect of milk fermented with Lactobacillus fermentum J20 (FMJ20) or J28 (FMJ28) on ameliorating indomethacin-induced inflammation. Twenty-eight male C57Bl/6 mice were divided into four experimental groups: indomethacin, indomethacin + FMJ20, indomethacin + FMJ28, and untreated (control). Groups were fed fermented milk for 15 days, followed by administration of indomethacin supplied in three sub-doses over experimental period. Body weight, and food consumption were recorded. Additionally, spleen, kidney, and liver were weighed, and the small intestine length was measured. The cytokines in serum (IL-2, IL-4, IL-6, IL-10, IL-17, IL-23 and TNFα) and in intestinal mucosa (IL-17 and IFNγ) were also determined. Compared to the control, all indomethacin-supplemented groups lost weight (~2.7 g; p < 0.05), but no changes were found in the organ-specific morphometry analysis. FMJ28 showed better results in attenuating serum and intestinal IL-17 levels. Furthermore, showed less epithelial cell loss and inflammatory infiltrates than the other indomethacin-treated groups. These results suggest that FMJ28 may be effective in reducing intestinal and systemic acute inflammation, specifically in mice.

Lactobacillus bulgaricus or Lactobacillus rhamnosus Suppresses NF-κB Signaling Pathway and Protects against AFB₁-Induced Hepatitis: A Novel Potential Preventive Strategy for Aflatoxicosis?

Aflatoxin B₁ (AFB₁), a mycotoxin found in food and feed, is immunotoxic to animals and poses significant threat to the food industry and animal production. The primary target of AFB₁ is the liver. To overcome aflatoxin toxicity, probiotic-mediated detoxification has been proposed. In the present study, to investigate the protective effects and molecular mechanisms of Lactobacillus bulgaricus or Lactobacillus rhamnosus against liver inflammatory responses to AFB₁, mice were administered with AFB₁ (300 μg/kg) and/or Lactobacillus intragastrically for 8 weeks. AML12 cells were cultured and treated with AFB₁, BAY 11-7082 (an NF-κB inhibitor), and different concentrations of L. bulgaricus or L. rhamnosus. The body weight, liver index, histopathological changes, biochemical indices, cytokines, cytotoxicity, and activation of the NF-κB signaling pathway were measured. AFB₁ exposure caused changes in liver histopathology and biochemical functions, altered inflammatory response, and activated the NF-κB pathway. Supplementation of L. bulgaricus or L. rhamnosus significantly prevented AFB₁-induced liver injury and alleviated histopathological changes and inflammatory response by decreasing NF-κB p65 expression. The results of in vitro experiments revealed that L.rhamnosus evidently protected against AFB₁-induced inflammatory response and decreased NF-κB p65 expression when compared with L. bulgaricus. These findings indicated that AFB₁ exposure can cause inflammatory response by inducing hepatic injury, and supplementation of L. bulgaricus or L. rhamnosus can produce significant protective effect against AFB₁-induced liver damage and inflammatory response by regulating the activation of the NF-κB signaling pathway.

DHA-phospholipids (DHA-PL) and EPA-phospholipids (EPA-PL) prevent intestinal dysfunction induced by chronic stress

DHA-PL and EPA-PL may effectively protect mice against intestinal dysfunction under chronic stress exposure.

Effects of heat-treated Lactobacillus crispatus KT-11 strain consumption on improvement of oral cavity environment: a randomised double-blind clinical trial

Heat-treated lactic acid bacteria is added to some foods because it is easier to store and transport, and have less interference with other food ingredient compared with living lactic acid bacteria. We have reported that oral administration of heat-treated Lactobacillus crispatus KT-11 strain (KT-11) suppressed the symptoms of periodontal disease in mice orally infected with Porphyromonas gingivalis. However, the preventive effect of KT-11 on periodontal disease in human is unclear. The aim of this randomised double-blind clinical trial was to examine the effects of KT-11 consumption on the oral environment in healthy volunteers. Sixteen healthy volunteers were randomly assigned to two groups (KT-11 or placebo), and they consumed a KT-11 food tablet (1.2×1010 KT-11 cells) or a placebo food tablet (without KT-11) every day for 4 weeks. Clinical parameters including numbers of major periodontopathic bacteria in saliva, plaque score, gum conditions, and oral mucosal fluid level were evaluated at weeks 0 and 4. Amount of change in P. gingivalis numbers decreased in the KT-11 group compared to that in the placebo group at week 4. Female participants in the KT-11 group had decreased plaque scores, reddish tinge, and gingival swelling scores compared to those in the placebo group at week 4. Furthermore, male participants in the KT-11 group demonstrated increased oral mucosa fluid scores. These clinical findings suggest that daily KT-11 intake can prevent periodontal disease through the improvement of oral conditions.

Probiotics for inflammatory bowel diseases: a promising adjuvant treatment

Inflammatory bowel diseases (IBD) encompass ulcerative colitis (UC), Crohn's disease (CD) and indeterminate colitis (IC), characterising chronic inflammation in the gastrointestinal tract, associated with changes in the immune system and in the intestinal microbiota. Thus, probiotics may offer an alternative or adjuvant approach to conventional therapy. The present review aims to summarise the mechanisms of action of probiotics in IBD and their therapeutic effects. Most of the studies suggest that probiotics are effective in the treatment of UC, especially when several strains are concomitantly administered. Species of Lactobacillus and Bifidobacterium genres are the most commonly used, and some studies even indicate that it is possible to replace medical therapy with probiotic supplementation. Regarding CD, the results of clinical trials are controversial and do not support the use of probiotics in this disease. In conclusion, probiotic supplementation is a promising adjuvant treatment in UC, but not in CD.

Probiotic Lactobacillus sakei proBio-65 Extract Ameliorates the Severity of Imiquimod Induced Psoriasis-Like Skin Inflammation in a Mouse Model

This study was designed to evaluate the protective effect of ethanol extract (SEL001) isolated from a potent probiotic strain Lactobacillus sakei proBio-65 on imiquimod (IMQ)-induced psoriasis-like skin inflammation in a mouse model. Histopathological and histomorphometrical changes in the ear and dorsal skin tissues were observed under hematoxylin and eosin stain for general histopathological architectures or Masson's trichrome stain for collagen fibers. The expression profile of psoriasis-associated specific genes was determined using Real-Time PCR analysis. As a result, topical application of IMQ resulted in a significant increase of mean total and epithelial (epidermis) thicknesses, the number of inflammatory cells infiltrated in the dermis, and the decrease of dermis collagen fiber occupied regions in the ear tissues of IMQ and IMQ plus vaseline treated groups when compared to the intact control group. A significant increase of epithelial thickness and number of inflammatory cells infiltrated in the dermis of dorsal skin tissues were also noticed in IMQ and IMQ plus vaseline treated groups as compared to the intact control group, suggesting classic IMQ-induced hypersensitive psoriasis. IMQ-induced hypersensitive psoriasis related histopathological changes to the ear and dorsal skin tissues were significantly inhibited by the treatment of a standard drug clobetasol and SEL001. Further, mRNA expression analysis indicated a significant increase in gene expression levels of pro-inflammatory cytokines, including IL-19, IL-17A, and IL-23 in IMQ and IMQ plus vaseline treated groups than that of the control. Clobetasol and SEL001 treated groups resulted in a lower gene expression level of IL-19, IL-17A, and IL-23 as compared to IMQ and IMQ plus vaseline treated groups. These results enforce that SEL001 could be a novel treatment for psoriasis and an alternative to other drugs that pose a number of side effects on the skin.

Modulation of Gut Microbiota: A Novel Paradigm of Enhancing the Efficacy of Programmed Death-1 and Programmed Death Ligand-1 Blockade Therapy

Blockade of programmed death 1 (PD-1) protein and its ligand programmed death ligand 1 (PD-L1) has been used as cancer immunotherapy in recent years, with the blockade of PD-1 being more widely used than blockade of PD-L1. PD-1 and PD-L1 blockade therapy showed benefits in patients with various types of cancer; however, such beneficial effects were seen only in a subgroup of patients. Improving the efficacy of PD-1 and PD-L1 blockade therapy is clearly needed. In this review, we summarize the recent studies on the effects of gut microbiota on PD-1 and PD-L1 blockade and discuss the new perspectives on improving efficacy of PD-1 and PD-L1 blockade therapy in cancer treatment through modulating gut microbiota. We also discuss the possibility that chronic infections or inflammation may impact on PD-1 and PD-L1 blockade therapy.

Lactobacillus rhamnosus L34 Attenuates Gut Translocation-Induced Bacterial Sepsis in Murine Models of Leaky Gut

Gastrointestinal (GI) bacterial translocation in sepsis is well known, but the role of Lactobacillus species probiotics is still controversial. We evaluated the therapeutic effects of Lactobacillus rhamnosus L34 in a new sepsis model of oral administration of pathogenic bacteria with GI leakage induced by either an antibiotic cocktail (ATB) and/or dextran sulfate sodium (DSS). GI leakage with ATB, DSS, and DSS plus ATB (DSS+ATB) was demonstrated by fluorescein isothiocyanate (FITC)-dextran translocation to the circulation. The administration of pathogenic bacteria, either Klebsiella pneumoniae or Salmonella enterica serovar Typhimurium, enhanced translocation. Bacteremia was demonstrated within 24 h in 50 to 88% of mice with GI leakage plus the administration of pathogenic bacteria but not with GI leakage induction alone or bacterial gavage alone. Salmonella bacteremia was found in only 16 to 29% and 0% of mice with Salmonella and Klebsiella administrations, respectively. Klebsiella bacteremia was demonstrated in 25 to 33% and 10 to 16% of mice with Klebsiella and Salmonella administrations, respectively. Lactobacillus rhamnosus L34 attenuated GI leakage in these models, as shown by the reductions of FITC-dextran gut translocation, serum interleukin-6 (IL-6) levels, bacteremia, and sepsis mortality. The reduction in the amount of fecal Salmonella bacteria with Lactobacillus treatment was demonstrated. In addition, an anti-inflammatory effect of the conditioned medium from Lactobacillus rhamnosus L34 was also demonstrated by the attenuation of cytokine production in colonic epithelial cells in vitro In conclusion, Lactobacillus rhamnosus L34 attenuated the severity of symptoms in a murine sepsis model induced by GI leakage and the administration of pathogenic bacteria.

The application of molecular topology for ulcerative colitis drug discovery

INTRODUCTION

Although the therapeutic arsenal against ulcerative colitis has greatly expanded (including the revolutionary advent of biologics), there remain patients who are refractory to current medications while the safety of the available therapeutics could also be improved. Molecular topology provides a theoretic framework for the discovery of new therapeutic agents in a very efficient manner, and its applications in the field of ulcerative colitis have slowly begun to flourish. Areas covered: After discussing the basics of molecular topology, the authors review QSAR models focusing on validated targets for the treatment of ulcerative colitis, entirely or partially based on topological descriptors. Expert opinion: The application of molecular topology to ulcerative colitis drug discovery is still very limited, and many of the existing reports seem to be strictly theoretic, with no experimental validation or practical applications. Interestingly, mechanism-independent models based on phenotypic responses have recently been reported. Such models are in agreement with the recent interest raised by network pharmacology as a potential solution for complex disorders. These and other similar studies applying molecular topology suggest that some therapeutic categories may present a 'topological pattern' that goes beyond a specific mechanism of action.

Effect of Lactobacillus casei strain Shirota-fermented milk on metabolic abnormalities in obese prediabetic Japanese men: a randomised, double-blind, placebo-controlled trial

An obesity-related prediabetic state is characterised by metabolic abnormalities such as post-glucose load hyperglycaemia and dyslipidaemia and consequently increases the risk for type 2 diabetes and cardiovascular disease. This study aimed to investigate the effects of Lactobacillus casei strain Shirota (LcS) on metabolic abnormalities in obese prediabetic subjects in a randomised, double-blind, placebo-controlled trial. Herein, 100 obese subjects (body mass index ≥25), who had moderate post-load hyperglycaemia (1-hr post-load plasma glucose (PG) levels ≥180 mg/dl during the oral glucose tolerance test), consumed LcS-fermented milk or placebo milk daily for 8 weeks. The post-load PG and fasting blood markers were evaluated. Although post-load PG levels were not significantly different between the groups, 1-hr post-load PG, glycoalbumin, and HbA1c levels decreased at 8 weeks compared with the baseline levels only in the LcS group (p=0.036, p=0.002, and p=0.006, respectively). The reduction in glycoalbumin levels was statistically significantly greater in the LcS group than in the placebo group (p=0.030). Stratified analyses revealed significantly improved 1-hr post-load PG and glycoalbumin levels in the LcS group compared with the placebo group among subjects with severe glucose intolerance (2-hr post-load PG levels higher than the median at baseline; p=0.036 and p=0.034, respectively). In terms of lipidic outcomes, total, low-density lipoprotein, and non-high-density lipoprotein cholesterol levels were significantly lower in the LcS group than in the placebo group (p=0.023, p=0.022, and p=0.008, respectively). These findings suggest that LcS may favourably affect metabolic abnormalities in obese prediabetic subjects, though the effects on glycaemic control may be limited.