Clinical effects and gut microbiota changes of using probiotics, prebiotics or synbiotics in inflammatory bowel disease: a systematic review and meta-analysis

Systematically-designed mixtures outperform single fibers for gut microbiota support

Dietary fiber interventions to modulate the gut microbiota have largely relied on isolated fibers or specific fiber sources. We hypothesized that fibers systematically blended could promote more health-related bacterial groups. Initially, pooled in vitro fecal fermentations were used to design dietary fiber mixtures to support complementary microbial groups related to health. Then, microbial responses were compared for the designed mixtures versus their single fiber components in vitro using fecal samples from a separate cohort of 10 healthy adults. The designed fiber mixtures outperformed individual fibers in supporting bacterial taxa across donors resulting in superior alpha diversity and unexpected higher SCFA production. Moreover, unique shifts in community structure and specific taxa were observed for fiber mixtures that were not observed for single fibers, suggesting a synergistic effect when certain fibers are put together. Fiber mixture responses were remarkably more consistent than individual fibers across donors in promoting several taxa, especially butyrate producers from the Clostridium cluster XIVa. This is the first demonstration of synergistic fiber interactions for superior support of a diverse group of important beneficial microbes consistent across people, and unexpectedly high SCFA production. Overall, harnessing the synergistic potential of designed fiber mixtures represents a promising and more efficacious avenue for future prebiotic development.

Polyphenols-rich Portulaca oleracea L. (purslane) alleviates ulcerative colitis through restiring the intestinal barrier, gut microbiota and metabolites

Ulcerative colitis (UC) is a recurrent intestinal disease caused by a complex of factors, and there are serious adverse effects and tolerance problems associated with the current long-term use of therapeutic drugs. The development of natural food sources and multi-targeted drugs for the treatment of UC is imminent. Portulaca oleracea L. (PO), as a vegetable, has been shown in studies to have an anti-UC effects. However, the relationship between the abundant active ingredients contained in Portulaca oleracea L. and the improvement of intestinal barrier, gut microbiota and metabolites is unclear. In the present study, Portulaca oleracea L. which was found to be rich in phenolic acid-based active ingredients, were effective in alleviating dextran sulfate sodium (DSS)-induced body weight loss, disease activity index (DAI) score and colon length in mice. It also decreased C-reactive protein (CRP) and myeloperoxidase (MPO) responses, reduced the permeation of fluorescein isothiocyanate (FITC)-dextran, lipopolysaccharide (LPS) and evans blue (EB), and improved histopathological scores. Meanwhile, in vitro and in vivo validation revealed the protective effects of purslane on the intestinal barrier indicators ZO-1, Occludin and Claudin-1, and inhibited the expression of inflammation-associated iNOS and NLRP3 proteins through the NF-κB signaling pathway. In addition, purslane increased the diversity of the intestinal flora, enhancing the proportion of the genera Butyricoccus, Dorea and Bifidobacterium and decreasing the percentage of Bacteroides, Turicibacter and Parabacteroides. Serum metabolomics analysis showed that the imbalance of 39 metabolites was significantly reversed after PO deployment. Enrichment analysis showed that Pentose phosphate pathway and Pyruvate metabolism pathway were the key pathways of PO against UC. Overall, purslane effectively improved the intestinal barrier disruption and intestinal inflammation by inhibiting the NF-κB signaling pathway, and adjusted the disorder of gut microbiota and metabolites to exert anti-UC effects.

Impact of Ligilactobacillus salivarius Li01 on benzo[a]pyrene-induced colitis, based on host-microbiome interactions in Mongolian gerbils

Background

Probiotics supplementations have been regarded as an effective strategy for colitis treatment. However, the effect of Ligilactobacillus salivarius Li01 on benzo[a]pyrene (BaP)-induced colitis in Mongolian gerbils remains unclear. In this study, we leverage a BaP-induced model of colitis that exhibits significant remission following Ligilactobacillus salivarius Li01 intervention, to conduct an animal experiment that integrates histopathological assessment, inflammatory cytokines, 16S rRNA sequencing, targeted metabolomic profiling to investigate the relationship between Ligilactobacillus salivarius Li01, gut microbiota, and colitis.

Results

We demonstrated that the improvements in colon histopathological assessment and inflammatory cytokines by Ligilactobacillus salivarius Li01 supplementation are accompanied by alterations in gut microbiota structure marked by increased abundance of strains with probiotic potential belonging to Bifidobacterium and Eubacterium_coprostanoligenes. Targeted metabolomic profiling analysis showed that Ligilactobacillus salivarius Li01 supplementation increases the concentration of acetic, propionic, butyric, and valeric acid. Correlation analysis showed that the alteration in the indicators associated with colitis is closely correlated to the changed microbial taxa and short-chain fatty acids (SCFAs).

Conclusion

These data highlighted that Ligilactobacillus salivarius Li01 supplementation ameliorated the BaP-induced colitis, probably via modulating the structure of gut microbiota and promoting the production of SCFAs. Our findings provide preliminary evidence for a possible therapeutic strategy for the treatment of colitis based on host-microbiome interactions.

Ameba-inspired strategy enhances probiotic efficacy via prebound nutrient supply

Nutrient competition with indigenous microbes or pathogens presents a significant challenge for oral probiotic efficacy. To address this issue, we develop an ameba-inspired food-carrying strategy (AIFS) by prebinding ginger-derived exosome-like nanoparticles (GELNs) onto probiotics as food depots. AIFS enables probiotics to efficiently and exclusively consume GELNs in situ, even in the presence of competing bacteria. This results in up to 21 times higher uptake efficiency compared to unengineered probiotics, dramatically accelerating probiotic proliferation. Meanwhile, AIFS potentiates probiotics' resistance to multiple GI stressors. In a murine model of colitis, AIFS can improve the abundance of probiotics and inhibit pathogens, maintaining intestinal flora homeostasis. Additionally, it can upregulate the anti-inflammatory IL-10, reduce the proinflammatory IL-1β, and repair damaged intestinal mucus. Thereby, AIFS displays potently elevated prophylactic and therapeutic efficacy for colitis mice. This work provides a method for microbial engineering, with broad implications for microbiotherapy and gut health.

Targeting gut microbiota dysbiosis in inflammatory bowel disease: a systematic review of current evidence

Introduction

The dysbiosis of the gut microbiota has been identified as a central factor in the pathogenesis of inflammatory bowel disease (IBD), a chronic condition characterized by frequent recurrence and various adverse effects of traditional therapies. While treatments targeting the gut microbiota show promise, their efficacy in IBD management still requires extensive evaluation. Our systematic review analyzes recent studies to elucidate the advancements and challenges in treating IBD using microbial-based therapies.

Methods

Through a comprehensive systematic review spanning key scientific databases-PubMed, Embase, Cochrane, Web of Science, Scopus, and Google Scholar-we scrutinized the impact of probiotics, prebiotics, synbiotics, and fecal microbiota transplantation (FMT) on individuals with IBD. Our detailed analysis covered study and participant demographics, along with seven key outcome measures: disease activity index, inflammatory markers, serum cytokines, microbiome composition, adverse effects, and the rates of remission and relapse.

Results

From 6,080 initial search hits, we included 71 studies that assessed various interventions compared to placebo or standard medical therapy. Although there was notable variation in clinical results while assessing different outcomes, overall, probiotics, prebiotics, and synbiotics enhanced the success rates in inducing remission among IBD patients. Furthermore, we noted significant reductions in levels of pro-inflammatory markers and cytokines. Additionally, the requirement for steroids, hospitalization, and poor outcomes in endoscopic and histological scores were significantly reduced in individuals undergoing FMT.

Conclusion

Our investigation highlights the potential of targeting gut microbiota dysbiosis with microbial-based therapies in patients with IBD. We recommend conducting larger, placebo-controlled randomized trials with extended follow-up periods to thoroughly assess these treatments' clinical efficacy and safety before widespread recommendations for clinical application.

The effect of oral synbiotics on the gut microbiota and inflammatory biomarkers in healthy adults: a systematic review and meta-analysis

CONTEXT

Prior research has explored the effect of synbiotics, the combination of probiotics and prebiotics, on the gut microbiota in clinical populations. However, evidence related to the effect of synbiotics on the gut microbiota in healthy adults has not been reviewed to date.

OBJECTIVE

A systematic review and meta-analysis was conducted to comprehensively investigate the effect of synbiotics on the gut microbiota and inflammatory markers in populations of healthy adults.

DATA SOURCES

Scopus, PubMed, Web of Science, ScienceDirect, MEDLINE, CINAHL, and The Cochrane Library were systematically searched to retrieve randomized controlled trials examining the primary outcome of gut microbiota or intestinal permeability changes after synbiotic consumption in healthy adults. Secondary outcomes of interest were short-chain fatty acids, inflammatory biomarkers, and gut microbiota diversity.

DATA EXTRACTION

Weighted (WMD) or standardized mean difference (SMD) outcome data were pooled in restricted maximum likelihood models using random effects. Twenty-seven articles reporting on 26 studies met the eligibility criteria (n = 1319).

DATA ANALYSIS

Meta-analyses of 16 studies showed synbiotics resulted in a significant increase in Lactobacillus cell count (SMD, 0.74; 95% confidence interval [CI], 0.15, 1.33; P = 0.01) and propionate concentration (SMD, 0.22; 95% CI, 0.02, 0.43; P = 0.03) compared with controls. A trend for an increase in Bifidobacterium relative abundance (WMD, 0.97; 95% CI, 0.42, 2.52; P = 0.10) and cell count (SMD, 0.82; 95% CI, 0.13, 1.88; P = 0.06) was seen. No significant differences in α-diversity, acetate, butyrate, zonulin, IL-6, CRP, or endotoxins were observed.

CONCLUSION

This review demonstrates that synbiotics modulate the gut microbiota by increasing Lactobacillus and propionate across various healthy adult populations, and may result in increased Bifidobacterium. Significant variations in synbiotic type, dose, and duration should be considered as limitations when applying findings to clinical practice.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO no. CRD42021284033.

[The intestinal microbiota in inflammatory bowel diseases]

BACKGROUND

The intestinal microbiota comprises all living microorganisms in the gastrointestinal tract and is crucial for its function. Clinical observations and laboratory findings confirm a central role of the microbiota in chronic inflammatory bowel diseases (IBD). However, many mechanistic details remain unclear.

OBJECTIVES

Changes in the microbiota and the causal relationship with the pathogenesis of IBD are described and current and future diagnostic and therapeutic options are discussed.

MATERIALS AND METHODS

Narrative review.

RESULTS

The intestinal microbiota is altered in composition, diversity, and function in IBD patients, but specific (universal) IBD-defining bacteria have not been identified. The healthy microbiota has numerous anti-inflammatory functions such as the production of short-chain fatty acids or competition with pathogens. In contrast, the IBD microbiota promotes inflammation through the destruction of the intestinal barrier and direct interaction with the immune system. The balance between pro- and anti-inflammatory effects of the microbiota appears to be crucial for the development of intestinal inflammation. Microbiota-based IBD diagnostics show promise but are not yet ready for clinical use. Probiotics and fecal microbiota transplantation have clinical effects, especially in ulcerative colitis, but the potential of microbiota-based therapies is far from being fully realized.

CONCLUSION

IBD dysbiosis remains undefined so far. It is unclear how the many parallel pro- and anti-inflammatory mechanisms contribute to IBD pathogenesis. An inadequate mechanistic understanding hinders the development of microbiota-based diagnostics and therapies.

The Interplay of Nutrition, the Gut Microbiota and Immunity and Its Contribution to Human Disease

Nutrition, the gut microbiota and immunity are all important factors in the maintenance of health. However, there is a growing realization of the complex interplay between these elements coalescing in a nutrition-gut microbiota-immunity axis. This regulatory axis is critical for health with disruption being implicated in a broad range of diseases, including autoimmune disorders, allergies and mental health disorders. This new perspective continues to underpin a growing number of innovative therapeutic strategies targeting different elements of this axis to treat relevant diseases. This review describes the inter-relationships between nutrition, the gut microbiota and immunity. It then details several human diseases where disruption of the nutrition-gut microbiota-immunity axis has been identified and presents examples of how the various elements may be targeted therapeutically as alternate treatment strategies for these diseases.

Recent advances in clinical practice: mastering the challenge-managing IBS symptoms in IBD

Many patients with IBD report persisting symptoms, despite resolution of the inflammatory process. Although by definition, a diagnosis of IBS cannot be made, the prevalence of 'IBS in IBD' surpasses the rate of IBS in the global population by fivefold. Because IBS-like symptoms are associated with a decreased quality of life and increased healthcare utilisation in IBD, diagnosis and treatment are necessary. In this review, we summarise the current knowledge on IBS-like symptoms in IBD. A pathophysiological common ground is present, which includes genetic susceptibility, environmental triggers, gut microbial dysbiosis, increased intestinal permeability, visceral hypersensitivity and involvement of brain-gut interaction. When symptoms persist after resolution of inflammation, other GI diseases should be excluded based on the chief complaint, considering any possible psychological co-morbidity early in the diagnostic work-up. Subsequent treatment should be initiated that is evidence-based and often multimodal, including classical and non-classical pharmacological agents as well as lifestyle and microbiota-based approaches, spanning the breadth of the gut, brain and its interaction. Treatment goals in this substantial part of the IBD population should be adapted to not only focus on treating the inflammation but taking care of the patient.

Effects of non-pharmacological interventions on gut microbiota and intestinal permeability in older adults: A systematic review: Non-pharmacological interventions on gut microbiota/barrier

This systematic review appraised previous findings of non-pharmacological interventions on gut microbiota and/ or intestinal permeability in older adults. A literature search was performed using PubMed, Scopus, ScienceDirect and the Cochrane Library. Relevant studies were shortlisted based on the inclusion and exclusion criteria, and evaluated for risks of bias using the "Cochrane Collaboration's Risk of Bias 2" and the "NIH Quality Assessment Tool for Before-After (Pre-Post) Studies with No Control Group". The primary outcomes were the effects of non-pharmacological interventions on gut microbiota diversity and composition, and intestinal permeability in older adults. Out of 85,114 studies, 38 were shortlisted. Generally, the non-pharmacological interventions were beneficial against dysbiosis and the leaky gut in older adults. Considering specific interventions with two or more studies that reported consistent outcomes, a pattern was observed amongst the Mediterranean diet (MD), polyphenol-rich (PR) diet and supplements (i.e., probiotics, prebiotics and synbiotics). As for the other interventions, the very few studies that have been conducted did not allow a strong conclusion to be made just yet. The MD (single and multidomain interventions) restored gut microbiota by increasing species richness (alpha diversity) and reduced intestinal permeability (zonulin) and inflammation (CRP). The PR diet only showed slight changes in the gut microbiota but improved the gut barrier by reducing zonulin, CRP and IL-6. Probiotics, prebiotics and synbiotics increased the genus Bifidobacterium spp. which are considered beneficial bacteria. This review has uncovered insights into the relationship between gut microbiota and intestinal epithelial barriers of specific non-pharmacological interventions in older adults.

Gut microbiome-targeted therapies as adjuvant treatments in inflammatory bowel diseases: a systematic review and network meta-analysis

BACKGROUND AND AIM

Gut microbiome-targeted therapies (MTTs), including prebiotics, probiotics, synbiotics, and fecal microbiota transplantation (FMT), have been widely used in inflammatory bowel diseases (IBD), but the best MTTs has not yet been confirmed. We performed a network meta-analysis (NMA) to examine this in ulcerative colitis (UC) and Crohn's disease (CD).

METHODS

We searched for randomized controlled trials (RCTs) on the efficacy and safety of MTTs as adjuvant therapies for IBD until December 10, 2023. Data were pooled using a random effects model, with efficacy reported as pooled relative risks with 95% CIs, and interventions ranked according to means of surfaces under cumulative ranking values.

RESULTS

Thirty-eight RCTs met the inclusion criteria. Firstly, we compared the efficacy of MTTs in IBD patients. Only FMT and probiotics were superior to placebo in all outcomes, but FMT ranked best in improving clinical response rate and clinical and endoscopic remission rate, and probiotics ranked second in reducing clinical relapse rate showed significant efficacy, while prebiotics ranked first showed nonsignificant efficacy. Subsequently, we conducted NMA for specific MTT formulations in UC and CD separately, which revealed that FMT, especially combined FMT via colonoscopy and enema, showed significant efficacy and was superior in improving clinical response and remission rate of active UC patients. As for endoscopic remission and clinical relapse, multistrain probiotics based on specific genera of Lactobacillus and Bifidobacterium showed significant efficacy and ranked best in UC. In CD, we found that no MTTs were significantly better than placebo, but synbiotics comprising Bifidobacterium and fructo-oligosaccharide/inulin mix and Saccharomyces ranked best in improving clinical remission and reducing clinical relapse, respectively. Moreover, FMT was safe in both UC and CD.

CONCLUSIONS

FMT and multistrain probiotics showed superior efficacy in UC. However, the efficacy of MTTs varies among different IBD subtypes and disease stages; thus, the personalized treatment strategies of MTTs are necessary.

Recognizing the biological barriers and pathophysiological characteristics of the gastrointestinal tract for the design and application of nanotherapeutics

The gastrointestinal tract (GIT) is an important and complex system by which humans to digest food and absorb nutrients. The GIT is vulnerable to diseases, which may led to discomfort or even death in humans. Therapeutics for GIT disease treatment face multiple biological barriers, which significantly decrease the efficacy of therapeutics. Recognizing the biological barriers and pathophysiological characteristics of GIT may be helpful to design innovative therapeutics. Nanotherapeutics, which have special targeting and controlled therapeutic release profiles, have been widely used for the treatment of GIT diseases. Herein, we provide a comprehensive review of the biological barrier and pathophysiological characteristics of GIT, which may aid in the design of promising nanotherapeutics for GIT disease treatment. Furthermore, several typical diseases of the upper and lower digestive tracts, such as Helicobacter pylori infection and inflammatory bowel disease, were selected to investigate the application of nanotherapeutics for GIT disease treatment.

Lactiplantibacillus plantarum L47 and inulin affect colon and liver inflammation in piglets challenged by enterotoxigenic Escherichia coli through regulating gut microbiota

Introduction

Infection by pathogenic bacteria during weaning is a common cause of diarrhea and intestinal inflammation in piglets. Supplementing the diet with synbiotics is beneficial for animal health. The strain of Lactiplantibacillus plantarum L47 (L47) isolated in our lab exhibited good probiotic properties when combined with inulin. Here, the effectiveness of combining L47 and inulin (CLN) in protecting against enterotoxigenic Escherichia coli (ETEC) induced colon and liver inflammation in weaned piglets was evaluated.

Methods

Twenty-eight piglets aged 21 days were randomly assigned into 4 groups: CON (control), LI47 (oral CLN culture fluid, 1010 CFU/d of L47 and 1 g/d of inulin), ECON (oral ETEC culture fluid, 1010 CFU/d), and ELI47 (oral CLN and ETEC culture fluid). After 24 days, the colon and liver samples were collected for further analysis.

Results and discussion

CLN alleviated colon damage caused by ETEC challenge, as evidenced by an increase of colonic crypt depth, mRNA expression of tight junction Claudin-1 and Occludin, GPX activity, the concentration of IL-10 and sIgA (p < 0.05). Moreover, there was a decrease in MDA activity, the load of E. coli, the concentration of LPS, gene expression of TLR4, and the concentration of TNF-α and IL-6 (p < 0.05) in colonic mucosa. Additionally, CLN counteracted liver damage caused by ETEC challenge by modulating pathways associated with immunity and disease occurrence (p < 0.05).

Conclusion

Supplementing with CLN alleviated colon inflammation induced by ETEC challenge by decreasing the E. coli/LPS/TLR4 pathway and regulating hepatic immune response and disease-related pathways, suggesting that CLN could protect intestinal and liver health in animals.

Dietary Lactobacillus johnsonii-derived extracellular vesicles ameliorate acute colitis by regulating gut microbiota and maintaining intestinal barrier homeostasis

Inflammatory bowel disease (IBD) is a chronic gastrointestinal disease with intricate pathogenesis, and clinical treatment is still not ideal. The imbalance of gut microbiota is associated with IBD progression. Various probiotics have been used as functional foods for the prevention and treatment of IBD, but the specific mechanism is still not fully understood. Lactobacillus johnsonii (L. johnsonii) is a potential anti-inflammatory bacterium, and compared to other probiotic Lactobacillus species, its colonization in the gut of colitis patients is significantly reduced. In this study, we first found that dietary L. johnsonii exerts strong anti-inflammatory and antioxidant effects in colitis mice, and this beneficial effect is directly related to its derived extracellular vesicles (LJ-EVs). Further experimental results indicate that LJ-EVs effectively prevented colitis symptoms and modulated gut microbiota and metabolic pathways. Meanwhile, we have studied for the first time the protective effect of LJ-EVs on the intestinal barrier from the perspective of reducing oxidative stress. We found that LJ-EVs can be directly taken up by intestinal epithelial cells and activate the Nrf2/HO-1 antioxidant signaling pathway, reducing endotoxin damage to cells and maintaining intestinal barrier homeostasis, which cascades to alleviate intestinal inflammation response. This study reveals the mechanism of L. johnsonii in treating colitis and provides a new approach for the development of oral LJ-EVs for the treatment of colitis.

Design and reporting of prebiotic and probiotic clinical trials in the context of diet and the gut microbiome

Diet is a major determinant of the gastrointestinal microbiome composition and function, yet our understanding of how it impacts the efficacy of prebiotics and probiotics is limited. Here we examine current evidence of dietary influence on prebiotic and probiotic efficacy in human studies, including potential mechanisms. We propose that habitual diet be included as a variable in prebiotic and probiotic intervention studies. This recommendation is based on the potential mechanisms via which diet can affect study outcomes, either directly or through the gut microbiome. We consider the challenges and opportunities of dietary assessment in this context. Lastly, we provide recommendations for the design, conduct and reporting of human clinical trials of prebiotics and probiotics (and other biotic interventions) to account for any effect of diet and nutrition.

Review article: The role of the gut-brain axis in inflammatory bowel disease and its therapeutic implications

BACKGROUND

Treatments targeting the gut-brain axis (GBA) are effective at reducing symptom burden in irritable bowel syndrome (IBS). The prevalence of common mental disorders and IBS-type symptom reporting is significantly higher in inflammatory bowel disease (IBD) than would be expected, suggesting potential GBA effects in this setting. Manipulation of the GBA may offer novel treatment strategies in selected patients with IBD. We present a narrative review of the bi-directional effects of the GBA in IBD and explore the potential for GBA-targeted therapies in this setting.

METHODS

We searched MEDLINE, EMBASE, EMBASE Classic, PsychINFO, and the Cochrane Central Register of Controlled Trials for relevant articles published by March 2024.

RESULTS

The bi-directional relationship between psychological well-being and adverse longitudinal disease activity outcomes, and the high prevalence of IBS-type symptom reporting highlight the presence of GBA-mediated effects in IBD. Treatments targeting gut-brain interactions including brain-gut behavioural treatments, neuromodulators, and dietary interventions appear to be useful adjunctive treatments in a subset of patients.

CONCLUSIONS

Psychological morbidity is prevalent in patients with IBD. The relationship between longitudinal disease activity outcomes, IBS-type symptom reporting, and poor psychological health is mediated via the GBA. Proactive management of psychological health should be integrated into routine care. Further clinical trials of GBA-targeted therapies, conducted in selected groups of patients with co-existent common mental disorders, or those who report IBS-type symptoms, are required to inform effective integrated models of care in the future.

Biological Response of Treatment with Saffron Petal Extract on Cytokine-Induced Oxidative Stress and Inflammation in the Caco-2/Human Leukemia Monocytic Co-Culture Model

The pathogenesis of Inflammatory Bowel Disease (IBD) involves complex mechanisms, including immune dysregulation, gut microbiota imbalances, oxidative stress, and defects in the gastrointestinal mucosal barrier. Current treatments for IBD often have significant limitations and adverse side effects, prompting a search for alternative therapeutic strategies. Natural products with anti-inflammatory and antioxidant properties have demonstrated potential for IBD management. There is increasing interest in exploring food industry waste as a source of bioactive molecules with healthcare applications. In this study, a co-culture system of Caco-2 cells and PMA-differentiated THP-1 macrophages was used to simulate the human intestinal microenvironment. Inflammation was induced using TNF-α and IFN-γ, followed by treatment with Saffron Petal Extract (SPE). The results demonstrated that SPE significantly attenuated oxidative stress and inflammation by downregulating the expression of pro-inflammatory mediators such as iNOS, COX-2, IL-1β, and IL-6 via modulation of the NF-κB pathway. Given that NF-κB is a key regulator of macrophage-driven inflammation, our findings support further investigation of SPE as a potential complementary therapeutic agent for IBD treatment.

The emerging role of the gut microbiota and its application in inflammatory bowel disease

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, is a complex disorder with an unknown cause. However, the dysbiosis of the gut microbiome has been found to play a role in IBD etiology, including exacerbated immune responses and defective intestinal barrier integrity. The gut microbiome can also be a potential biomarker for several diseases, including IBD. Currently, conventional treatments targeting pro-inflammatory cytokines and pathways in IBD-associated dysbiosis do not yield effective results. Other therapies that directly target the dysbiotic microbiome for effective outcomes are emerging. We review the role of the gut microbiome in health and IBD and its potential as a diagnostic, prognostic, and therapeutic target for IBD. This review also explores emerging therapeutic advancements that target gut microbiome-associated alterations in IBD, such as nanoparticle or encapsulation delivery, fecal microbiota transplantation, nutritional therapies, microbiome/probiotic engineering, phage therapy, mesenchymal stem cells (MSCs), gut proteins, and herbal formulas.

Efficacy and safety of probiotics in IBD: An overview of systematic reviews and updated meta-analysis of randomized controlled trials

BACKGROUND AND OBJECTIVE

Probiotics show promise in inflammatory bowel disease (IBD), yet knowledge gaps persist. We performed an overview of systematic reviews and an updated metanalysis of randomized controlled trials (RCT) assessing the effect of probiotics on Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

MEDLINE, Web of Science, and the Cochrane Central Register of Controlled Trials were searched up to September 2023. Primary outcomes were clinical remission and recurrence; secondary outcomes included endoscopic response and remission, and adverse events. We calculated odds ratios (OR) using a random-effects model in R. The quality of systematic reviews was assessed using the AMSTAR-2; the trials' risk of bias was evaluated using the Cochrane Collaboration tool. Evidence certainty was rated using the GRADE framework.

RESULTS

Out of 2613 results, 67 studies (22 systematic reviews and 45 RCTs) met the eligibility criteria. In the updated meta-analysis, the OR for clinical remission in UC and CD was 2.00 (95% CI 1.28-3.11) and 1.61 (95% CI 0.21-12.50), respectively. The subgroup analysis suggested that combining 5-ASA and probiotics may be beneficial for inducing remission in mild-to-moderate UC (OR 2.35, 95% CI 1.29-4.28). Probiotics decreased the odds of recurrence in relapsing pouchitis (OR 0.03, 95% CI 0.00-0.25) and trended toward reducing clinical recurrence in inactive UC (OR 0.65, 95% CI 0.42-1.01). No protective effect against recurrence was identified for CD. Multi-strain formulations appear superior in achieving remission and preventing recurrence in UC. The use of probiotics was not associated with better endoscopic outcomes. Adverse events were similar to control. However, the overall certainty of evidence was low.

CONCLUSION

Probiotics, particularly multi-strain formulations, appear efficacious for the induction of clinical remission and the prevention of relapse in UC patients as well as for relapsing pouchitis. Notwithstanding, no significant effect was identified for CD. The favorable safety profile of probiotics was also highlighted.

Lactobacillus gasseri ATCC33323 affects the intestinal mucosal barrier to ameliorate DSS-induced colitis through the NR1I3-mediated regulation of E-cadherin

Inflammatory bowel disease (IBD) is an immune system disorder primarily characterized by colitis, the exact etiology of which remains unclear. Traditional treatment approaches currently yield limited efficacy and are associated with significant side effects. Extensive research has indicated the potent therapeutic effects of probiotics, particularly Lactobacillus strains, in managing colitis. However, the mechanisms through which Lactobacillus strains ameliorate colitis require further exploration. In our study, we selected Lactobacillus gasseri ATCC33323 from the intestinal microbiota to elucidate the specific mechanisms involved in modulation of colitis. Experimental findings in a DSS-induced colitis mouse model revealed that L. gasseri ATCC33323 significantly improved physiological damage in colitic mice, reduced the severity of colonic inflammation, decreased the production of inflammatory factors, and preserved the integrity of the intestinal epithelial structure and function. It also maintained the expression and localization of adhesive proteins while improving intestinal barrier permeability and restoring dysbiosis in the gut microbiota. E-cadherin, a critical adhesive protein, plays a pivotal role in this protective mechanism. Knocking down E-cadherin expression within the mouse intestinal tract significantly attenuated the ability of L. gasseri ATCC33323 to regulate colitis, thus confirming its protective role through E-cadherin. Finally, transcriptional analysis and in vitro experiments revealed that L. gasseri ATCC33323 regulates CDH1 transcription by affecting NR1I3, thereby promoting E-cadherin expression. These findings contribute to a better understanding of the specific mechanisms by which Lactobacillus strains alleviate colitis, offering new insights for the potential use of L. gasseri as an alternative therapy for IBD, particularly in dietary supplementation.

Fecal microbiota and metabolites in the pathogenesis and precision medicine for inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract, and its pathogenesis is believed to be associated with an imbalance between commensal organisms and the intestinal immune system. This imbalance is significantly influenced by the intestinal microbiota and metabolites and plays a critical role in maintaining intestinal mucosal homeostasis. However, disturbances in the intestinal microbiota cause dysregulated immune responses and consequently induce intestinal inflammation. Recent studies have illustrated the roles of the intestinal microbiota in the pathogenesis of IBD and underscored the potential of precision diagnosis and therapy. This work summarises recent progress in this field and particularly focuses on the application of the intestinal microbiota and metabolites in the precision diagnosis, prognosis assessment, treatment effectiveness evaluation, and therapeutic management of IBD.

The Microbiome in Inflammatory Bowel Disease

The management of patients with inflammatory bowel disease (IBD) aims to control inflammation through the use of immunosuppressive treatments that target various points in the inflammatory cascade. However, the efficacy of these therapies in the long term is limited, and they often are associated with severe side effects. Although the pathophysiology of the disease is not completely understood, IBD is regarded as a multifactorial disease that occurs due to an inappropriate immune response in genetically susceptible individuals. The gut microbiome is considered one of the main actors in the development of IBD. Gut dysbiosis, characterised by significant changes in the composition and functionality of the gut microbiota, often leads to a reduction in bacterial diversity and anti-inflammatory anaerobic bacteria. At the same time, bacteria with pro-inflammatory potential increase. Although changes in microbiome composition upon biological agent usage have been observed, their role as biomarkers is still unclear. While most studies on IBD focus on the intestinal bacterial population, recent studies have highlighted the importance of other microbial populations, such as viruses and fungi, in gut dysbiosis. In order to modulate the aberrant immune response in patients with IBD, researchers have developed therapies that target different players in the gut microbiome. These innovative approaches hold promise for the future of IBD treatment, although safety concerns are the main limitations, as their effects on humans remain unknown.

Diet and Microbiome-Directed Therapy 2.0 for IBD

Inflammatory bowel disease (IBD) comprises chronic and relapsing disorders of the gastrointestinal tract, characterized by dysregulated immune responses to the gut microbiome. The gut microbiome and diet are key environmental factors that influence the onset and progression of IBD and can be leveraged for treatment. In this review, we summarize the current evidence on the role of the gut microbiome and diet in IBD pathogenesis, and the potential of microbiome-directed therapies and dietary interventions to improve IBD outcomes. We discuss available data and the advantages and drawbacks of the different approaches to manipulate the gut microbiome, such as fecal microbiota transplantation, next-generation and conventional probiotics, and postbiotics. We also review the use of diet as a therapeutic tool in IBD, including the effects in induction and maintenance, special diets, and exclusive enteral nutrition. Finally, we highlight the challenges and opportunities for the translation of diet and microbiome interventions into clinical practice, such as the need for personalization, manufacturing and regulatory hurdles, and the specificity to take into account for clinical trial design.

Importance of Gut Microbiota in Patients with Inflammatory Bowel Disease

Inflammatory bowel diseases (IBDs), such as Crohn's disease (CD) and ulcerative colitis (UC), are chronic diseases of the digestive system with a multifactorial and not fully understood etiology. There is research suggesting that they may be initiated by genetic, immunological, and lifestyle factors. In turn, all of these factors play an important role in the modulation of intestinal microflora, and a significant proportion of IBD patients struggle with intestinal dysbiosis, which leads to the conclusion that intestinal microflora disorders may significantly increase the risk of developing IBD. Additionally, in IBD patients, Toll-like receptors (TLRs) produced by intestinal epithelial cells and dendritic cells treat intestinal bacterial antigens as pathogens, which causes a disruption of the immune response, resulting in the development of an inflammatory process. This may result in the occurrence of intestinal dysbiosis, which IBD patients are significantly vulnerable to. In this study, we reviewed scientific studies (in particular, systematic reviews with meta-analyses, being studies with the highest level of evidence) regarding the microflora of patients with IBD vs. the microflora in healthy people, and the use of various strains in IBD therapy.

The Function of Probiotics and Prebiotics on Canine Intestinal Health and Their Evaluation Criteria

Maintaining homeostasis within the intestinal microbiota is imperative for assessing the health status of hosts, and dysbiosis within the intestinal microbiota is closely associated with canine intestinal diseases. In recent decades, the modulation of canine intestinal health through probiotics and prebiotics has emerged as a prominent area of investigation. Evidence indicates that probiotics and prebiotics play pivotal roles in regulating intestinal health by modulating the intestinal microbiota, fortifying the epithelial barrier, and enhancing intestinal immunity. This review consolidates literature on using probiotics and prebiotics for regulating microbiota homeostasis in canines, thereby furnishing references for prospective studies and formulating evaluation criteria.

ACE2 mediates tryptophan alleviation on diarrhea by repairing intestine barrier involved mTOR pathway

The membrane-delimited receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), angiotensin-converting enzyme 2 (ACE2), which is expressed in the intestine, collaborates with broad neutral amino acid transporter 1 (B0AT1). Tryptophan (Trp) is transported into intestinal epithelial cells by ACE2 and B0AT1. However, whether ACE2 and its binding protein B0AT1 are involved in Trp-mediated alleviation of intestinal injury is largely unknown. Here, we used weaned piglets and IPEC-J2 cells as models and found that ACE2/B0AT1 alleviated lipopolysaccharide (LPS)-induced diarrhea and promoted intestinal barrier recovery via transport of Trp. The levels of the aryl hydrocarbon receptor (AhR) and mechanistic target of rapamycin (mTOR) pathways were altered by ACE2. Dietary Trp supplementation in LPS-treated weaned piglets revealed that Trp alleviated diarrhea by promoting ACE2/B0AT1 expression, and examination of intestinal morphology revealed that the damage to the intestinal barrier was repaired. Our study demonstrated that ACE2 accompanied by B0AT1 mediated the alleviation of diarrhea by Trp through intestinal barrier repair via the mTOR pathway.

Prevention and treatment of antibiotics-associated adverse effects through the use of probiotics: A review

BACKGROUND

The human gut hosts a diverse microbial community, essential for maintaining overall health. However, antibiotics, commonly prescribed for infections, can disrupt this delicate balance, leading to antibiotic-associated diarrhea, inflammatory bowel disease, obesity, and even neurological disorders. Recognizing this, probiotics have emerged as a promising strategy to counteract these adverse effects.

AIM OF REVIEW

This review aims to offer a comprehensive overview of the latest evidence concerning the utilization of probiotics in managing antibiotic-associated side effects.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Probiotics play a crucial role in preserving gut homeostasis, regulating intestinal function and metabolism, and modulating the host immune system. These mechanisms serve to effectively alleviate antibiotic-associated adverse effects and enhance overall well-being.

Immunomodulatory Activity on Human Macrophages by Cell-Free Supernatants to Explore the Probiotic and Postbiotic Potential of Lactiplantibacillus plantarum Strains of Plant Origin

Upon dietary administration, probiotic microorganisms can reach as live cells the human gut, where they interact with the microbiota and host cells, thereby exerting a beneficial impact on host functions, mainly through immune-modulatory activities. Recently, attention has been drawn by postbiotics, i.e. non-viable probiotic microbes, including their metabolic products, which possess biological activities that benefit the host. Lactiplantibacillus plantarum is a bacterial species that comprises recognised probiotic strains. In this study, we investigated in vitro the probiotic (and postbiotic) potential of seven L. plantarum strains, including five newly isolated from plant-related niches. The strains were shown to possess some basic probiotic attributes, including tolerance to the gastrointestinal environment, adhesion to the intestinal epithelium and safety. Besides, their cell-free culture supernatants modulated cytokine patterns in human macrophages in vitro, promoting TNF-α gene transcription and secretion, while attenuating the transcriptional activation and secretion of both TNF-α and IL-8 in response to a pro-inflammatory signal, and enhancing the production of IL-10. Some strains induced a high IL-10/IL-12 ratio that may correlate to an anti-inflammatory capacity in vivo. Overall, the investigated strains are good probiotic candidates, whose postbiotic fraction exhibits immunomodulatory properties that need further in vivo studies. The main novelty of this work consists in the polyphasic characterisation of candidate beneficial L. plantarum strains obtained from relatively atypical plant-associated niches, by an approach that explores both probiotic and postbiotic potentials, in particular studying the effect of microbial culture-conditioned media on cytokine pattern, analysed at both transcriptional and secretion level in human macrophages.

Recent progress on engineered micro/nanomaterials mediated modulation of gut microbiota for treating inflammatory bowel disease

Inflammatory bowel disease (IBD) is a type of chronic recurrent inflammation disease that mainly includes Crohn's disease and ulcerative colitis. Currently, the treatments for IBD remain highly challenging, with clinical treatment drugs showing limited efficacy and adverse side effects. Thus, developing drug candidates with comprehensive therapeutic effects, high efficiency, and low toxicity is urgently needed. Recently, micro/nanomaterials have attracted considerable interest because of their bioavailability, multitarget and efficient effects on IBD. In addition, gut modulation plays a substantial role in restoring intestinal homeostasis. Therefore, efficient microbiota-based strategies modulating gut microenvironment have great potential in remarkably treating IBD. With the development of micro- and nanomaterials for the treatment of IBD and more in-depth studies of their therapeutic mechanisms, it has been found that these treatments also have a tendency to positively regulate the intestinal flora, resulting in an increase in the beneficial flora and a decrease in the level of pathogenic bacteria, thus regulating the composition of the intestinal flora to a normal state. In this review, we first present the interactions among the immune system, intestinal barrier, and gut microbiome. In addition, recent advances in administration routes and methods that positively arouse the regulation of intestinal flora for IBD using probiotics, prebiotics, and redox-active micro/nanomaterials have been reviewed. Finally, the key challenges and critical perspectives of gut microbiota-based micro/nanomaterial treatment are also discussed.

Gastrointestinal microbiota-directed nutritional and therapeutic interventions for inflammatory bowel disease: opportunities and challenges

Evidence-based research has confirmed the role of gastrointestinal microbiota in regulating intestinal inflammation. These data have generated interest in developing microbiota-based therapies for the prevention and management of inflammatory bowel disease (IBD). Despite in-depth understanding of the etiology of IBD, it currently lacks a cure and requires ongoing management. Accumulating data suggest that an aberrant gastrointestinal microbiome, often referred to as dysbiosis, is a significant environmental instigator of IBD. Novel microbiome-targeted interventions including prebiotics, probiotics, fecal microbiota transplant, and small molecule microbiome modulators are being evaluated as therapeutic interventions to attenuate intestinal inflammation by restoring a healthy microbiota composition and function. In this review, the effectiveness and challenges of microbiome-centered interventions that have the potential to alleviate intestinal inflammation and improve clinical outcomes of IBD are explored.

Exploring the efficacy of a novel prebiotic-like growth promoter on broiler chicken production performance

This study attempts to isolate a candidate growth promoter from the ovine paunch waste and scrutinize its effects on the production performance of broiler chickens as compared to mannan-oligosaccharide (MOS), a prebiotic, and lincomycin, an antibiotic growth promoter (AB). The paunch waste collected from slaughtered sheep was processed to remove particulate matter. The clarified liquid was then added to an excess of ethanol (1:9 ratio), and the resultant precipitate {(novel growth-promoting paunch extract (NGPE)} was collected, dried, and stored. In vitro increase in cell density for probiotic bacteria viz. Lactobacillus rhamnosus and Enterococcus faecalis (Log10 CFU/ml) were significantly higher (P < 0.01) in NGPE supplemented media (2.78 ± 0.11 and 2.77 ± 0.10) as compared to that on MOS (1.28 ± 0.05 and 2.49 ± 0.09) and glucose (1.09 ± 0.04 and 1.12 ± 0.04) supplemented media. In the in-vivo trial of six weeks duration with broiler chickens (Cobb-400), NGPE supplementation resulted in significantly higher growth in weeks IV (P < 0.05) and VI (P < 0.01) of age in comparison to MOS and AGP supplemented groups, a lower (P < 0.01) cumulative feed conversion ratio in comparison to MOS supplemented groups, and a higher (P < 0.01) cumulative protein efficiency ratio compared to MOS and AGP supplementation. NGPE supplementation also lowered lipid peroxidation (P < 0.01), increased reduced glutathione activity (P < 0.01) in chicken erythrocytes, and boosted the lactic acid bacteria count in the cecal contents (P < 0.01). This is the first report of the isolation of a paunch waste extract that increased the in vitro growth of probiotic bacteria and improved the production performance of broiler chickens.

Integrative Multiomics Profiling Unveils the Protective Function of Ulinastatin against Dextran Sulfate Sodium-Induced Colitis

Ulcerative colitis is an inflammatory bowel disease with multiple pathogeneses. Here, we aimed to study the therapeutic role of ulinastatin (UTI), an anti-inflammatory bioagent, and its associated mechanisms in treating colitis. Dextran sulfate sodium was administrated to induce colitis in mice, and a subgroup of colitis mice was treated with UTI. The gut barrier defect and inflammatory manifestations of colitis were determined via histological and molecular experiments. In addition, transcriptomics, metagenomics, and metabolomics were employed to explore the possible mechanisms underlying the effects of UTI. We found that UTI significantly alleviated the inflammatory manifestations and intestinal barrier damage in the mice with colitis. Transcriptome sequencing revealed a correlation between the UTI treatment and JAK-STAT signaling pathway. UTI up-regulated the expression of SOCS1, which subsequently inhibited the phosphorylation of JAK2 and STAT3, thus limiting the action of inflammatory mediators. In addition, 16S rRNA sequencing illustrated that UTI maintained a more stable intestinal flora, protecting the gut from dysbiosis in colitis. Moreover, metabolomics analysis demonstrated that UTI indeed facilitated the production of some bile acids and short-chain fatty acids, which supported intestinal homeostasis. Our data provide evidence that UTI is effective in treating colitis and support the potential use of UTI treatment for patients with ulcerative colitis.

Feeding Broiler Chicks with Bacillus subtilis, Clostridium butyricum, and Enterococcus faecalis Mixture Improves Growth Performance and Regulates Cecal Microbiota

A total of 300 day-old Arbor Acres Plus broiler chicks (mixed sex) was used to evaluate the effects of dietary supplementation of Bacillus subtilis, Clostridium butyricum, and Enterococcus faecalis mixture (PB) on growth performance, ileal morphology, and cecal microbiota. All birds were randomly assigned into 3 groups based on the initial body weight. There were 5 replicate cages per group and 20 birds per cage. The experimental period was 42 days. Dietary treatments were based on a basal diet and supplemented with 0, 0.05, or 0.10% PB. The results indicated that broiler chicks fed with the diet supplemented with graded levels of PB have quadratically improved their body weight gain and feed intake; the highest value was presented in 0.05% PB-containing group. In addition, villus to crypt ratio linearly increased with the concentration of PB increased in the diet. The alpha diversity linearly increased by PB supplementation, and the highest value was presented in 0.10% PB-containing group. In terms of growth performance, the suitable dose of PB used in the diet was 0.05%. However, ternary plot showed that the harmful bacteria, Escherichia-Shigella, was enriched in 0.05% PB-containing group. In brief, we considered that dietary supplementation of graded levels of PB improved growth performance and regulated cecal microbiota in broiler chicks.

The Role of Gut Microbiome in the Pathogenesis and the Treatment of Inflammatory Bowel Diseases

Inflammatory bowel disease (IBD), which includes ulcerative colitis and Crohn's disease, is a chronic condition characterized by inflammation of the gastrointestinal tract. Its exact cause is unknown, but it's thought to result from a dysregulated immune response influenced by various factors, including changes in the intestinal microbiota, diet, lifestyle, and genetics. The gut microbiome, consisting of diverse microorganisms, plays a crucial role in maintaining physiological balance, with its disruption leading to inflammatory responses typical of IBD. Treatments primarily aim at symptom control, employing immunomodulators, corticosteroids, and newer approaches like probiotics, prebiotics, fecal transplants, and dietary modifications, all focusing on leveraging the microbiota's potential in disease management. These strategies aim to restore the delicate balance of the gut microbiome, typically altered in IBD, marked by a decrease in beneficial bacteria and an increase in harmful pathogens. This review underscores the importance of the gut microbiome in the pathogenesis and treatment of IBD, highlighting the shift towards personalized medicine and the necessity for further research in understanding the complex interactions between the gut microbiota, immune system, and genetics in IBD. It points to the potential of emerging treatments and the importance of a multifaceted approach in managing this complex and challenging disease.

The effects of synbiotic supplementation on blood pressure and other maternal outcomes in pregnant mothers with mild preeclampsia: a triple-blinded randomized controlled trial

INTRODUCTION

Preeclampsia affects a significant percentage of pregnancies which is a leading cause of premature birth. Probiotics have the potential to affect inflammatory factors, and oxidative stress, which are linked to the development of preeclampsia. The study aimed to compare the effect of synbiotic and placebo on blood pressure and pregnancy duration as primary outcomes, and other pregnancy outcomes.

METHODS

This study comprised 128 pregnant women with mild preeclampsia and gestational ages exceeding 24 weeks who were referred to the high-risk pregnancy clinic. It was a randomized, controlled, phase III, triple-blinded clinical experiment. The intervention and control groups were distributed to the participants at random. Intervention group received one oral synbiotic capsule, and control group received placebo daily until delivery. Based on gestational age at the time of diagnosis, preeclampsia was stratificated as early (< 34 weeks) or late (≥ 34 weeks). Data obtained from questionnaires, and biochemical serum factors were analyzed using SPSS software version 23 software.

RESULTS

With the exception of the history of taking vitamin D3, there were no statistically significant variations in socio-demographic variables between the research groups. After the intervention, the means of systolic blood pressure (adjusted mean difference: -13.54, 95% CI: -5.01 to -22.07), and diastolic blood pressure (adjusted mean difference: -10.30, 95% CI: -4.70 to -15.90) were significantly lower in the synbiotic-supplemented group than in the placebo group. Compared to the placebo group, the incidence of severe PE (p < 0.001), proteinuria (p = 0.044), and mean serum creatinine level (p = 0.005) significantly declined in the synbiotic-supplemented group after the intervention. However, our analysis found no significant association for other outcomes.

CONCLUSION

Based on our results, synbiotic had beneficial effects on some pregnancy outcomes. Further studies with larger samples are needed to verify the advantages of synbiotic supplementation for high-risk pregnancies, particularly with regards to higher doses, and longer intervention periods.

TRIAL REGISTRATION

IRCT20110606006709N20.

The Potential Impact of Probiotics on Human Health: An Update on Their Health-Promoting Properties

Probiotics, known to be live microorganisms, have been shown to improve or restore the gut microbiota, which in turn has been linked to improved health. It is believed that probiotics are the modern equivalent of a panacea, with claims that they may treat or prevent different diseases both in children and adults (e.g., from colic in babies to cardiovascular disease, respiratory infection, and cancer in adults). Ever since the early 2000s, probiotic-based fermented foods have had a resurgence in popularity, mostly due to claims made regarding their health benefits. Fermented foods have been associated with the prevention of irritable bowel syndrome, lactose intolerance, gastroenteritis, and obesity, but also other conditions such as chronic diarrhea, allergies, dermatitis, and bacterial and viral infections, all of which are closely related to an unhealthy lifestyle. Recent and ongoing developments in microbiome/microbiota science have given us new research directions for probiotics. The new types, mechanisms, and applications studied so far, and those currently under study, have a great potential to change scientific understanding of probiotics' nutritional applications and human health care. The expansion of fields related to the study of the microbiome and the involvement of probiotics in its improvement foreshadow an era of significant changes. An expanding range of candidate probiotic species is emerging that can address newly elucidated data-driven microbial niches and host targets. In the probiotic field, new variants of microbiome-modulating interventions are being developed, including prebiotics, symbiotics, postbiotics, microbial consortia, live biotherapeutic products, and genetically modified organisms, with renewed interest in polyphenols, fibers, and fermented foods to ensure human health. This manuscript aims to analyze recent, emerging, and anticipated trends in probiotics (sources, doses, mechanism of action, diseases for which probiotics are administered, side effects, and risks) and create a vision for the development of related areas of influence in the field.

The Networked Interaction between Probiotics and Intestine in Health and Disease: A Promising Success Story

Probiotics are known to promote human health either precautionary in healthy individuals or therapeutically in patients suffering from certain ailments. Although this knowledge was empirical in past tomes, modern science has already verified it and expanded it to new limits. These microorganisms can be found in nature in various foods such as dairy products or in supplements formulated for clinical or preventive use. The current review examines the different mechanisms of action of the probiotic strains and how they interact with the organism of the host. Emphasis is put on the clinical therapeutic use of these beneficial microorganisms in various clinical conditions of the human gastrointestinal tract. Diseases of the gastrointestinal tract and particularly any malfunction and inflammation of the intestines seriously compromise the health of the whole organism. The interaction between the probiotic strains and the host's microbiota can alleviate the clinical signs and symptoms while in some cases, in due course, it can intervene in the underlying pathology. Various safety issues of the use of probiotics are also discussed.

Mechanisms and Clinical Implications of Human Gut Microbiota-Drug Interactions in the Precision Medicine Era

The human gut microbiota, comprising trillions of microorganisms residing in the gastrointestinal tract, has emerged as a pivotal player in modulating various aspects of human health and disease. Recent research has shed light on the intricate relationship between the gut microbiota and pharmaceuticals, uncovering profound implications for drug metabolism, efficacy, and safety. This review depicted the landscape of molecular mechanisms and clinical implications of dynamic human gut Microbiota-Drug Interactions (MDI), with an emphasis on the impact of MDI on drug responses and individual variations. This review also discussed the therapeutic potential of modulating the gut microbiota or harnessing its metabolic capabilities to optimize clinical treatments and advance personalized medicine, as well as the challenges and future directions in this emerging field.

Traditional Chinese Medicine: A promising strategy to regulate the imbalance of bacterial flora, impaired intestinal barrier and immune function attributed to ulcerative colitis through intestinal microecology

ETHNOPHARMACOLOGICAL RELEVANCE

Globally, plant materials are widely used as an additional and alternative therapy for the treating of diverse diseases. Ulcerative colitis (UC) is a chronic, recurrent and nonspecific inflammation of the bowel, referred to as "modern intractable disease" according to the World Health Organization. With the continuous development of theoretical research in Traditional Chinese Medicine (TCM) and the advantages of TCM in terms of low side effects, TCM has shown great progress in the research of treating UC.

AIM OF THIS REVIEW

This review aimed to explore the correlation between intestinal microbiota and UC, summarize research advances in TCM for treating UC, and discuss the mechanism of action of TCM remedies in regulating intestinal microbiota and repairing damaged intestinal barrier, which will provide a theoretical basis for future studies to elucidate the mechanism of TCM remedies based on gut microbiota and provide novel ideas for the clinical treatment of UC.

METHODS

We have collected and collated relevant articles from different scientific databases in recent years on the use of TCM in treating UC in relation to intestinal microecology. Based on the available studies, the therapeutic effects of TCM are analysed and the correlation between the pathogenesis of UC and intestinal microecology is explored.

RESULTS

TCM is used to further protect the intestinal epithelium and tight junctions, regulate immunity and intestinal flora by regulating intestinal microecology, thereby achieving the effect of treating UC. Additionally, TCM remedies can effectively increase the abundance of beneficial bacteria that produce short-chain fatty acids, decrease the abundance of pathogenic bacteria, restore the balance of intestinal microbiota, and indirectly alleviate intestinal mucosal immune barrier dysfunction and promote the repair of damaged colorectal mucosa.

CONCLUSION

Intestinal microbiota is closely related to UC pathogenesis. The alleviation of intestinal dysbiosis can be a potential novel therapeutic strategy for UC. TCM remedies can exert protective and therapeutic effects on UC through various mechanisms. Although intestinal microbiota can aid in the identification of different TCM syndromes types, further studies are needed using modern medical technology. This will improve the clinical therapeutic efficacy of TCM remedies in UC and promote the application of precision medicine.

The INHABIT (synergIstic effect of aNtHocyAnin and proBIoTics in) Inflammatory Bowel Disease trial: a study protocol for a double-blind, randomised, controlled, multi-arm trial

Ulcerative Colitis (UC), a type of Inflammatory Bowel Disease (IBD), is a chronic, relapsing gastrointestinal condition with increasing global prevalence. The gut microbiome profile of people living with UC differs from healthy controls and this may play a role in the pathogenesis and clinical management of UC. Probiotics have been shown to induce remission in UC; however, their impact on the gut microbiome and inflammation is less clear. Anthocyanins, a flavonoid subclass, have shown anti-inflammatory and microbiota-modulating properties; however, this evidence is largely preclinical. To explore the combined effect and clinical significance of anthocyanins and a multi-strain probiotic, a 3-month randomised controlled trial will be conducted in 100 adults with UC. Participants will be randomly assigned to one of four groups: anthocyanins (blackcurrant powder) + placebo probiotic, probiotic + placebo fruit powder, anthocyanin + probiotic, or double placebo. The primary outcome is a clinically significant change in the health-related quality-of-life measured with the Inflammatory Bowel Disease Questionnaire-32. Secondary outcomes include shotgun metagenomic sequencing of the faecal microbiota, faecal calprotectin, symptom severity, and mood and cognitive tests. This research will identify the role of adjuvant anti-inflammatory dietary treatments in adults with UC and elucidate the relationship between the gut microbiome and inflammatory biomarkers in this disease, to help identify targeted individualised microbial therapies. ANZCTR registration ACTRN12623000630617.

Gut microbiota in pathophysiology, diagnosis, and therapeutics of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a multifactorial disease, which is thought to be an interplay between genetic, environment, microbiota, and immune-mediated factors. Dysbiosis in the gut microbial composition, caused by antibiotics and diet, is closely related to the initiation and progression of IBD. Differences in gut microbiota composition between IBD patients and healthy individuals have been found, with reduced biodiversity of commensal microbes and colonization of opportunistic microbes in IBD patients. Gut microbiota can, therefore, potentially be used for diagnosing and prognosticating IBD, and predicting its treatment response. Currently, there are no curative therapies for IBD. Microbiota-based interventions, including probiotics, prebiotics, synbiotics, and fecal microbiota transplantation, have been recognized as promising therapeutic strategies. Clinical studies and studies done in animal models have provided sufficient evidence that microbiota-based interventions may improve inflammation, the remission rate, and microscopic aspects of IBD. Further studies are required to better understand the mechanisms of action of such interventions. This will help in enhancing their effectiveness and developing personalized therapies. The present review summarizes the relationship between gut microbiota and IBD immunopathogenesis. It also discusses the use of gut microbiota as a noninvasive biomarker and potential therapeutic option.

Comparative efficacy and tolerability of probiotic, prebiotic, and synbiotic formulations for adult patients with mild-moderate ulcerative colitis in an adjunctive therapy: A network meta-analysis

BACKGROUND & AIMS

Probiotics, prebiotics, and synbiotics (PPS) have been widely used as adjuvant treatments in patients with ulcerative colitis (UC) in recent years. However, the most effective formulations of PPS have yet to be identified. We thus aimed to compare the efficacy and tolerability of different PPS formulations for mild-moderate UC.

METHODS

We searched PubMed, Embase, Web of Science, and Cochrane CENTRAL from inception to June 24, 2023 for double-blind randomized controlled trials. We used a frequentist approach in random-effects models for network meta-analysis and the Grading of Recommendations Assessment, Development, and Evaluation approach to evaluate the certainty of evidence.

RESULTS

We analysed data from 20 trials involving 1153 patients. The combinations of specific strains of Lactobacillus and Bifidobacterium (CLB) (odds ratio (OR), 3.85; 95 % confidence interval (CI), 1.40-10.60; low certainty) and combinations of specific strains of Lactobacillus, Bifidobacterium, and Streptococcus (CLBS) (OR, 2.20; 95 % CI, 1.47-3.28; low certainty) significantly increased the clinical remission rate in intention-to-treat analysis (ITT) when compared to placebo. Similarly, compared with placebo, the two combinations significantly reduced clinical activity scores (standardized mean difference (SMD), -1.17 (95 % CI, -1.68 to -0.65), low certainty; and SMD, -1.33 (95 % CI, -1.81 to -0.86), low certainty, respectively). Hierarchical cluster analyses showed the two combinations formed clusters with high efficacy (clinical remission in ITT and clinical activity score) and tolerability (withdrawal due to worsening symptoms) within 12 weeks.

CONCLUSION

In this systematic review, we found CLB and CLBS demonstrated a clinical benefit in adjuvant treatments, with a comparable tolerability and safety profile to placebo. Further trials are needed.

TRIAL REGISTRATION NUMBER

CRD42022344905.

SARS-CoV-2 infection threatening intestinal health: A review of potential mechanisms and treatment strategies

The outbreak of the COVID-19 pandemic has brought great problems to mankind, including economic recession and poor health. COVID-19 patients are frequently reported with gastrointestinal symptoms such as diarrhea and vomiting in clinical diagnosis. Maintaining intestinal health is the key guarantee to maintain the normal function of multiple organs, otherwise it will be a disaster. Therefore, the purpose of this review was deeply understanded the potential mechanism of SARS-CoV-2 infection threatening intestinal health and put forward reasonable treatment strategies. Combined with the existing researches, we summarized the mechanism of SARS-CoV-2 infection threatening intestinal health, including intestinal microbiome disruption, intestinal barrier dysfunction, intestinal oxidative stress and intestinal cytokine storm. These adverse intestinal events may affect other organs through the circulatory system or aggravate the course of the disease. Typically, intestinal disadvantage may promote the progression of SARS-CoV-2 through the gut-lung axis and increase the disease degree of COVID-19 patients. In view of the lack of specific drugs to inhibit SARS-CoV-2 replication, the current review described new strategies of probiotics, prebiotics, postbiotics and nutrients to combat SARS-CoV-2 infection and maintain intestinal health. To provide new insights for the prevention and treatment of gastrointestinal symptoms and pneumonia in patients with COVID-19.

Anti-inflammatory effects of probiotics and synbiotics on patients with non-alcoholic fatty liver disease: An umbrella study on meta-analyses

BACKGROUND AND AIM

The impact of chronic low-grade inflammation in the development of non-alcoholic fatty liver disease (NAFLD) has been studied widely. Previous studies showed gut pathogens' effects on inflammation development in NAFLD patients; hence, hypothetically, gut microbial therapy by administration of probiotics, synbiotics, and prebiotics may alleviate inflammation in these individuals. Several studies were performed in this regard; however, conflicting results were obtained. In this study, we aimed to comprehensively evaluate the effects of gut microbial therapy on inflammatory markers in NAFLD patients in a meta-umbrella design.

METHODS

Two independent researchers investigated international databases, including PubMed, Web of Science, Scopus, and Cochrane Library, from inception until March 2023. Meta-analyses evaluating the impact of probiotics, synbiotics, or prebiotics on inflammatory markers of patients with NAFLD were eligible for our study. AMASTAR 2 checklist was used to evaluate the quality of included studies. Random effect model was performed for the analysis, and Egger's regression test was conducted to determine publication bias.

RESULTS

A total number of 12 studies were entered into our analysis. Our findings revealed that gut microbial therapy could significantly reduce serum C-reactive protein (CRP) levels among NAFLD patients (ES: -0.58; 95% CI: -0.73, -0.44, P < 0.001). In subgroup analysis, this reduction was observed with both probiotics (ES: -0.63; 95% CI: -0.81, -0.45, P < 0.001) and synbiotics (ES: -0.49; 95% CI: -0.74, -0.24, P < 0.001). In addition, gut microbial therapy could significantly decrease tumor necrosis factor-a (TNF-a) levels in NAFLD patients (ES: -0.48; 95% CI: -0.67 to -0.30, P < 0.001). In subgroup analysis, this decrease was observed with probiotics (ES: -0.32; 95% CI: -0.53, -0.11, P = 0.002) and synbiotics (ES: -0.96; 95% CI: -1.32, -0.60, P < 0.001). Not enough information was available for assessing prebiotics' impacts.

CONCLUSION

The results of this umbrella review suggest that probiotics and synbiotics have promising effects on inflammatory markers, including TNF-a and CRP; however, more research is needed regarding the effects of prebiotics.

PROSPERO REGISTRATION CODE

CRD42022346998.

Recent Advances in Nanozyme-Based Materials for Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a type of chronic inflammatory disorder that interferes with the patient's lifestyle and, in extreme situations, can be deadly. Fortunately, with the ever-deepening understanding of the pathological cause of IBD, recent studies using nanozyme-based materials have indicated the potential toward effective IBD treatment. In this review, the recent advancement of nanozymes for the treatment of enteritis is summarized from the perspectives of the structural design of nanozyme-based materials and therapeutic strategies, intending to serve as a reference to produce effective nanozymes for moderating inflammation in the future. Last but not least, the potential and current restrictions for using nanozymes in IBD will also be discussed. In short, this review may provide a guidance for the development of innovative enzyme-mimetic nanomaterials that offer a novel and efficient approach toward the effective treatment of IBD.

Role of mucosal immunity and epithelial-vascular barrier in modulating gut homeostasis

The intestinal mucosa represents the most extensive human barrier having a defense function against microbial and food antigens. This barrier is represented externally by a mucus layer, consisting mainly of mucins, antimicrobial peptides, and secretory immunoglobulin A (sIgA), which serves as the first interaction with the intestinal microbiota. Below is placed the epithelial monolayer, comprising enterocytes and specialized cells, such as goblet cells, Paneth cells, enterochromaffin cells, and others, each with a specific protective, endocrine, or immune function. This layer interacts with both the luminal environment and the underlying lamina propria, where mucosal immunity processes primarily take place. Specifically, the interaction between the microbiota and an intact mucosal barrier results in the activation of tolerogenic processes, mainly mediated by FOXP3+ regulatory T cells, underlying intestinal homeostasis. Conversely, the impairment of the mucosal barrier function, the alteration of the normal luminal microbiota composition (dysbiosis), or the imbalance between pro- and anti-inflammatory mucosal factors may result in inflammation and disease. Another crucial component of the intestinal barrier is the gut-vascular barrier, formed by endothelial cells, pericytes, and glial cells, which regulates the passage of molecules into the bloodstream. The aim of this review is to examine the various components of the intestinal barrier, assessing their interaction with the mucosal immune system, and focus on the immunological processes underlying homeostasis or inflammation.

Prebiotics Progress Shifts in the Intestinal Microbiome That Benefits Patients with Type 2 Diabetes Mellitus

Hypoglycemic medications that could be co-administered with prebiotics and functional foods can potentially reduce the burden of metabolic diseases such as Type 2 Diabetes Mellitus (T2DM). The efficacy of drugs such as metformin and sulfonylureas can be enhanced by the activity of the intestinal microbiome elaborated metabolites. Functional foods such as prebiotics (e.g., oligofructose) and dietary fibers can treat a dysbiotic gut microbiome by enhancing the diversity of microbial niches in the gut. These beneficial shifts in intestinal microbiome profiles include an increased abundance of bacteria such as Faecalibacterium prauznitzii, Akkermancia muciniphila, Roseburia species, and Bifidobacterium species. An important net effect is an increase in the levels of luminal SCFAs (e.g., butyrate) that provide energy carbon sources for the intestinal microbiome in cross-feeding activities, with concomitant improvement in intestinal dysbiosis with attenuation of inflammatory sequalae and improved intestinal gut barrier integrity, which alleviates the morbidity of T2DM. Oligosaccharides administered adjunctively with pharmacotherapy to ameliorate T2DM represent current plausible treatment modalities.

Dietary Fat Modulation of Gut Microbiota and Impact on Regulatory Pathways Controlling Food Intake

Obesity is a multifactorial disease that continues to increase in prevalence worldwide. Emerging evidence has shown that the development of obesity may be influenced by taxonomic shifts in gut microbiota in response to the consumption of dietary fats. Further, these alterations in gut microbiota have been shown to promote important changes in satiation signals including gut hormones (leptin, ghrelin, GLP-1, peptide YY and CCK) and orexigenic and anorexigenic neuropeptides (AgRP, NPY, POMC, CART) that influence hyperphagia and therefore obesity. In this review, we highlight mechanisms by which gut microbiota can influence these satiation signals both locally in the gastrointestinal tract and via microbiota-gut-brain communication. Then, we describe the effects of dietary interventions and associated changes in gut microbiota on satiety signals through microbiota-dependent mechanisms. Lastly, we present microbiota optimizing therapies including prebiotics, probiotics, synbiotics and weight loss surgery that can help restore beneficial gut microbiota by enhancing satiety signals to reduce hyperphagia and subsequent obesity. Overall, a better understanding of the mechanisms by which dietary fats induce taxonomical shifts in gut microbiota and their impact on satiation signaling pathways will help develop more targeted therapeutic interventions in delaying the onset of obesity and in furthering its treatment.