Randomised clinical trial: the effectiveness of Lactobacillus reuteri ATCC 55730 rectal enema in children with active distal ulcerative colitis

Probiotic formulations and gastro-intestinal diseases in the paediatric population: a narrative review

Background/Aim

Probiotics are live microbial supplements that improve the microbial balance in the host animal when administered in adequate amounts. They play an important role in relieving symptoms of many diseases associated with gastrointestinal tract, for example, in necrotizing enterocolitis (NEC), antibiotic-associated diarrhea, relapsing Clostridium difficile colitis, Helicobacter pylori infections, and inflammatory bowel disease (IBD). In this narrative review, the authors aim to evaluate the role of different probiotic formulations in treating gastrointestinal diseases in pediatric population aged 18 years or younger and highlight the main considerations for selecting probiotic formulations for use in this population.

Methodology

The authors searched PubMed and Clinicaltrials.gov from inception to 24th July 2022, without any restrictions. Using an iterative process, the authors subsequently added papers through hand-searching citations contained within retrieved articles and relevant systematic reviews and meta-analyses.

Results

The effectiveness of single-organism and composite probiotics in treating gastrointestinal disorders in pediatric patients aged 18 or under were analyzed and compared in this study. A total of 39 studies were reviewed and categorized based on positive and negative outcomes, and compared with a placebo, resulting in 25 studies for single-organism and 14 studies for composite probiotics. Gastrointestinal disorders studied included NEC, acute gastroenteritis (AGE), Acute Diarrhea, Ulcerative Colitis (UC), and others. The results show that probiotics are effective in treating various gastrointestinal disorders in children under 18, with single-organism probiotics demonstrating significant positive outcomes in most studies, and composite probiotics showing positive outcomes in all studies analyzed, with a low incidence of negative outcomes for both types.

Conclusion

This study concludes that single-organism and composite probiotics are effective complementary therapies for treating gastrointestinal disorders in the pediatric population. Hence, healthcare professionals should consider using probiotics in standard treatment regimens, and educating guardians can enhance the benefits of probiotic therapy. Further research is recommended to identify the optimal strains and dosages for specific conditions and demographics. The integration of probiotics in clinical practice and ongoing research can contribute to reducing the incidence and severity of gastrointestinal disorders in pediatric patients.

Probiotics for inflammatory bowel disease: Is there sufficient evidence?

Inflammatory bowel disease (IBD) refers to chronic inflammatory disorders of the gut. Ulcerative colitis (UC) and Crohn's disease (CD) are two subtypes of IBD. Evidence suggests that the intestinal microbiota plays a role in the pathogenesis of IBD, so probiotics have garnered a lot of interest as a potential treatment or prevention for IBD. However, clinical evidence of the efficacy of probiotics is still debatable. We performed a literature review. An advanced search considered clinical studies on probiotic for IBD from inception to 2023 in PubMed, Embase, Cochrane Library, and Web of Science. In the treatment of UC with probiotics, only Escherichia coli Nissle 1917 for maintenance treatment of UC in remission, and Bifidobacterium and VSL#3 for induction of remission in patients with mild to moderately active UC have shown strong evidence. Currently, there are no definitive conclusions regarding the effectiveness of probiotics in CD. The mechanism of probiotic treatment for IBD may be related to reducing oxidative stress, repairing the intestinal barrier, regulating intestinal flora balance, and modulating intestinal immune response. Differences in the benefits of probiotics between CD and UC may be attributable to the different lesion extent and immune-mediated pathophysiology. More robust randomized clinical trials are required to validate the efficacy and safety of diverse probiotic strains in IBD.

Additive efficacy and safety of probiotics in the treatment of ulcerative colitis: a systematic review and meta-analysis

BACKGROUND

We aim to report the latest pooled analyses to evaluate the additive efficacy and safety of probiotics in the treatment of ulcerative colitis (UC).

METHODS

We systematically searched the relevant literature investigating the efficacy and/or safety of probiotics in patients with UC from PubMed, Embase and Web of Science up to January 2023. Two researchers independently screened the literature, extracted data, and evaluated the quality of the included studies according to the inclusion and exclusion criteria. Any discrepancies throughout these processes were solved by consensus. All statistical analyses were performed by Review Manager version 5.4 and Stata version 15.0.

RESULTS

A total of 13 articles were included in the pooled analyses, and the studies were all randomized controlled trials with a total of 930 patients. There were no significant differences between the probiotics and placebo groups concerning demographic and baseline characteristics. For patients with active UC, the probiotic group boosted the remission rate by 87% compared to the placebo group, but failed to reach a statistical difference (OR: 1.87; 95% CI 0.98, 3.57; P = 0.06, I2 = 67%); furthermore, there were no statistical differences in maintenance of clinical remission, clinical response, change in UCDAI scores, or mucosal healing outcomes in the probiotic group compared to the placebo group. For patients in clinical remission, the clinical relapse rates were significantly lower in the probiotic group than in the placebo group (OR: 0.34; 95% CI 0.14, 0.79; P = 0.01). Moreover, this study did not observe a significant difference between the two groups for general adverse events rate (OR: 1.98; 95% CI 0.69, 5.68; P = 0.20).

CONCLUSION

Probiotic-assisted therapy may be effective in inhibiting UC recurrence in patients in clinical remission without increasing the risk of treatment-related adverse events; furthermore, probiotics may increase the rate of clinical remission in patients with active UC. However, caution is needed when interpreting the clinical efficacy of probiotics in improving the clinical outcome of patients with active UC.

Nutraceuticals and biotics in pediatric gastrointestinal disorders

In recent years there has been growing interest in the use of nutraceuticals and biotics in both pediatric and adult clinical practice. The overlapping and often ambiguous symptoms of both functional and organic gastrointestinal disorders have led to a search for alternative therapeutic approaches that avoid the use of synthetic or chemical treatments. However, while nutraceuticals and natural supplements are widely used, their health benefits are often not supported by adequate scientific evidence, and an unregulated use of nutraceuticals can be potentially harmful. The correct use of nutraceuticals, prebiotics, and probiotics can optimize the results of drug therapy in some cases and reduce the risk of side effects. This review aims to provide clinicians with guidance on the use of complementary therapies for pediatric gastrointestinal symptoms and disorders, highlighting the scarcity of studies on the kinetics and dynamics of nutraceuticals and biotics. While it is generally difficult to associate their intakes with adverse events due to the often-coexisting pharmacological treatments, it is essential to avoid the abandonment of traditional drugs with proven efficacy in the treatment of single diseases. Overall, the use of nutraceuticals, prebiotics, and probiotics in pediatric gastroenterological practice requires caution and medical supervision. Further research is needed to determine the effects of alternative therapies on pediatric gastrointestinal symptoms and disorders, and to ensure their safe and effective use in the clinical practice.

Gut Microbiome Disruption Following SARS-CoV-2: A Review

COVID-19 has been associated with having a negative impact on patients' gut microbiome during both active disease and in the post-acute phase. In acute COVID-19, rapid alteration of the gut microbiome composition was observed, showing on one side a reduction in beneficial symbionts (e.g., Roseburia, Lachnospiraceae) and on the other side an increase in opportunistic pathogens such as Enterococcus and Proteobacteria. Alpha diversity tends to decrease, especially initially with symptom onset and hospital admission. Although clinical recovery appears to align with improved gut homeostasis, this process could take several weeks, even in mild infections. Moreover, patients with COVID-19 post-acute syndrome showed changes in gut microbiome composition, with specific signatures associated with decreased respiratory function up to 12 months following acute disease. Potential treatments, especially probiotic-based therapy, are under investigation. Open questions remain on the possibility to use gut microbiome data to predict disease progression and on potential confounders that may impair result interpretation (e.g., concomitant therapies in the acute phase; reinfection, vaccines, and occurrence of novel conditions or diseases in the post-acute syndrome). Understanding the relationships between gut microbiome dynamics and disease progression may contribute to better understanding post-COVID syndrome pathogenesis or inform personalized treatment that can affect specific targets or microbiome markers.

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.

Reviewing the potential of probiotics, prebiotics and synbiotics: advancements in treatment of ulcerative colitis

Inflammatory bowel diseases (IBD) like Crohn's and ulcerative colitis (UC) are multifactorial pathologies caused by environmental factors and genetic background. UC is a chronic inflammatory disorder that specifically targets the colon, resulting in inflammation. Various chemical interventions, including aminosalicylates, corticosteroids, immunomodulators, and biological therapies, have been extensively employed for the purpose of managing symptoms associated with UC. Nevertheless, it is important to note that these therapeutic interventions may give rise to undesirable consequences, including, but not limited to, the potential for weight gain, fluid retention, and heightened vulnerability to infections. Emerging therapeutic approaches for UC are costly due to their chronic nature. Alternatives like synbiotic therapy, combining prebiotics and probiotics, have gained attention for mitigating dysbiosis in UC patients. Prebiotics promote beneficial bacteria proliferation, while probiotics establish a balanced gut microbiota and regulate immune system functionality. The utilisation of synbiotics has been shown to improve the inflammatory response and promote the resolution of symptoms in individuals with UC through the stimulation of beneficial bacteria growth and the enhancement of intestinal barrier integrity. Hence, this review article aims to explore the potential benefits and underlying reasons for incorporating alternative approaches in the management of UC with studies performed using prebiotics, probiotics, and synbiotics to treat ulcerative colitis and to highlight safety and considerations in UC and future perspectives. This will facilitate the utilisation of novel treatment strategies for the safer and more efficacious management of patients with UC.

The Role of Gut Microbiome Supplementation in COVID-19 Management

COVID-19, which is caused by the RNA virus, SARS-CoV-2, mainly affects the respiratory system and has a varied clinical presentation. However, several studies have shown that COVID-19 can also affect the gastrointestinal (GI) system. Patients can experience various GI symptoms, such as vomiting and diarrhea, and the virus has been detected in the stool samples of patients hospitalized with COVID-19. There have also been rare reports of COVID-19 presenting with isolated GI symptoms and lack of respiratory symptoms, and the virus has also been detected for prolonged periods in the fecal samples of COVID-19 patients. Major alterations in the gut microbiome in the form of depletion of beneficial organisms and an abundance of pathogenic organisms have been reported in the fecal samples of hospitalized COVID-19 patients. Although the US FDA has approved several drugs to manage COVID-19, their efficacy remains modest. So, there is a constant ongoing effort to investigate novel treatment options for COVID-19. Health supplements like probiotics, prebiotics, postbiotics, and synbiotics have been popularly known for their various health benefits. In this review, we have summarized the current literature, which shows the potential benefit of these health supplements to mitigate and/or prevent the clinical presentation of COVID-19.

Chemotherapy-induced gastrointestinal toxicity: Pathogenesis and current management

Chemotherapy is the most common treatment for malignant tumors. However, chemotherapy-induced gastrointestinal toxicity (CIGT) has been a major concern for cancer patients, which reduces their quality of life and leads to treatment intolerance and even cessation. Nevertheless, prevention and treatment for CIGT are challenging, due to the prevalence and complexity of the condition. Chemotherapeutic drugs directly damage gastrointestinal mucosa to induce CIGT, including nausea, vomiting, anorexia, gastrointestinal mucositis, and diarrhea, etc. The pathogenesis of CIGT involves multiple factors, such as gut microbiota disorders, inflammatory responses and abnormal neurotransmitter levels, that synergistically contribute to its occurrence and development. In particular, the dysbiosis of gut microbiota is usually linked to abnormal immune responses that increases inflammatory cytokines' expression, which is a common characteristic of many types of CIGT. Chemotherapy-induced intestinal neurotoxicity is also a vital concern in CIGT. Currently, modern medicine is the dominant treatment of CIGT, however, traditional Chinese medicine (TCM) has attracted interest as a complementary and alternative therapy that can greatly alleviate CIGT. Accordingly, this review aimed to comprehensively summarize the pathogenesis and current management of CIGT using PubMed and Google Scholar databases, and proposed that future research for CIGT should focus on the gut microbiota, intestinal neurotoxicity, and promising TCM therapies, which may help to develop more effective interventions and optimize managements of CIGT.

Lactobacillus reuteri in digestive system diseases: focus on clinical trials and mechanisms

Objectives

Digestive system diseases have evolved into a growing global burden without sufficient therapeutic measures. Lactobacillus reuteri (L. reuteri) is considered as a new potential economical therapy for its probiotic effects in the gastrointestinal system. We have provided an overview of the researches supporting various L. reuteri strains' application in treating common digestive system diseases, including infantile colic, diarrhea, constipation, functional abdominal pain, Helicobacter pylori infection, inflammatory bowel disease, diverticulitis, colorectal cancer and liver diseases.

Methods

The summarized literature in this review was derived from databases including PubMed, Web of Science, and Google Scholar.

Results

The therapeutic effects of L. reuteri in digestive system diseases may depend on various direct and indirect mechanisms, including metabolite production as well as modulation of the intestinal microbiome, preservation of the gut barrier function, and regulation of the host immune system. These actions are largely strain-specific and depend on the activation or inhibition of various certain signal pathways. It is well evidenced that L. reuteri can be effective both as a prophylactic measure and as a preferred therapy for infantile colic, and it can also be recommended as an adjuvant strategy to diarrhea, constipation, Helicobacter pylori infection in therapeutic settings. While preclinical studies have shown the probiotic potential of L. reuteri in the management of functional abdominal pain, inflammatory bowel disease, diverticulitis, colorectal cancer and liver diseases, its application in these disease settings still needs further study.

Conclusion

This review focuses on the probiotic effects of L. reuteri on gut homeostasis via certain signaling pathways, and emphasizes the importance of these probiotics as a prospective treatment against several digestive system diseases.

Probiotics for the treatment of ulcerative colitis: a review of experimental research from 2018 to 2022

Ulcerative colitis (UC) has become a worldwide public health problem, and the prevalence of the disease among children has been increasing. The pathogenesis of UC has not been elucidated, but dysbiosis of the gut microbiota is considered the main cause of chronic intestinal inflammation. This review focuses on the therapeutic effects of probiotics on UC and the potential mechanisms involved. In animal studies, probiotics have been shown to alleviate symptoms of UC, including weight loss, diarrhea, blood in the stool, and a shortened colon length, while also restoring intestinal microecological homeostasis, improving gut barrier function, modulating the intestinal immune response, and attenuating intestinal inflammation, thereby providing theoretical support for the development of probiotic-based microbial products as an adjunctive therapy for UC. However, the efficacy of probiotics is influenced by factors such as the bacterial strain, dose, and form. Hence, the mechanisms of action need to be investigated further. Relevant clinical trials are currently lacking, so the extension of animal experimental findings to clinical application requires a longer period of consideration for validation.

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.

The role of complex interactions between the intestinal flora and host in regulating intestinal homeostasis and inflammatory bowel disease

Pharmacological treatment of inflammatory bowel disease (IBD) is inefficient and difficult to discontinue appropriately, and enterobacterial interactions are expected to provide a new target for the treatment of IBD. We collected recent studies on the enterobacterial interactions among the host, enterobacteria, and their metabolite products and discuss potential therapeutic options. Intestinal flora interactions in IBD are affected in the reduced bacterial diversity, impact the immune system and are influenced by multiple factors such as host genetics and diet. Enterobacterial metabolites such as SCFAs, bile acids, and tryptophan also play important roles in enterobacterial interactions, especially in the progression of IBD. Therapeutically, a wide range of sources of probiotics and prebiotics exhibit potential therapeutic benefit in IBD through enterobacterial interactions, and some have gained wide recognition as adjuvant drugs. Different dietary patterns and foods, especially functional foods, are novel therapeutic modalities that distinguish pro-and prebiotics from traditional medications. Combined studies with food science may significantly improve the therapeutic experience of patients with IBD. In this review, we provide a brief overview of the role of enterobacteria and their metabolites in enterobacterial interactions, discuss the advantages and disadvantages of the potential therapeutic options derived from such metabolites, and postulate directions for further research.

A probiotic bi-functional peptidoglycan hydrolase sheds NOD2 ligands to regulate gut homeostasis in female mice

Secreted proteins are one of the direct molecular mechanisms by which microbiota influence the host, thus constituting a promising field for drug discovery. Here, through bioinformatics-guided screening of the secretome of clinically established probiotics from Lactobacillus, we identify an uncharacterized secreted protein (named LPH here) that is shared by most of these probiotic strains (8/10) and demonstrate that it protects female mice from colitis in multiple models. Functional studies show that LPH is a bi-functional peptidoglycan hydrolase with both N-Acetyl-β-D-muramidase and DL-endopeptidase activities that can generate muramyl dipeptide (MDP), a NOD2 ligand. Different active site mutants of LPH in combination with Nod2 knockout female mice confirm that LPH exerts anti-colitis effects through MDP-NOD2 signaling. Furthermore, we validate that LPH can also exert protective effects on inflammation-associated colorectal cancer in female mice. Our study reports a probiotic enzyme that enhances NOD2 signaling in vivo in female mice and describes a molecular mechanism that may contribute to the effects of traditional Lactobacillus probiotics.

Microbiota-derived tryptophan catabolites mediate the chemopreventive effects of statins on colorectal cancer

Epidemiological studies have indicated an association between statin use and reduced incidence of colorectal cancer (CRC), and work in preclinical models has demonstrated a potential chemopreventive effect. Statins are also associated with reduced dysbiosis in the gut microbiome, yet the role of the gut microbiome in the protective effect of statins in CRC is unclear. Here we validated the chemopreventive role of statins by retrospectively analysing a cohort of patients who underwent colonoscopies. This was confirmed in preclinical models and patient cohorts, and we found that reduced tumour burden was partly due to statin modulation of the gut microbiota. Specifically, the gut commensal Lactobacillus reuteri was increased as a result of increased microbial tryptophan availability in the gut after atorvastatin treatment. Our in vivo studies further revealed that L. reuteri administration suppressed colorectal tumorigenesis via the tryptophan catabolite, indole-3-lactic acid (ILA). ILA exerted anti-tumorigenic effects by downregulating the IL-17 signalling pathway. This microbial metabolite inhibited T helper 17 cell differentiation by targeting the nuclear receptor, RAR-related orphan receptor γt (RORγt). Together, our study provides insights into an anti-cancer mechanism driven by statin use and suggests that interventions with L. reuteri or ILA could complement chemoprevention strategies for CRC.

Effect of probiotics as an immune modulator for the management of COVID-19

COVID-19, an acute respiratory viral infection conveyed by pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has affected millions of individuals globally, and is a public health emergency of international concern. Till now, there are no highly effective therapies for this infection without vaccination. As they can evolve quickly and cross the strain level easily, these viruses are causing epidemics or pandemics that are allied with more severe clinical diseases. A new approach is needed to improve immunity to confirm the protection against emerging viral infections. Probiotics can modify gut microbial dysbiosis, improve the host immune system, and stimulate immune signaling, increasing systemic immunity. Several probiotic bacterial therapies have been proven to decrease the period of bacterial or viral infections. Superinduction of inflammation, termed cytokine storm, has been directly linked with pneumonia and severe complications of viral respiratory infections. In this case, probiotics as potential immunomodulatory agents can be an appropriate candidate to improve the host's response to respiratory viral infections. During this COVID-19 pandemic, any approach that can induce mucosal and systemic immunity could be helpful. Here, we summarize contexts regarding the effectiveness of various probiotics for preventing virus-induced respiratory infectious diseases, especially those that could be employed for COVID-19 patients. In addition, the effects of probiotics, their mechanisms on different aspects of immune responses against respiratory viral infection, and their antiviral properties in clinical findings have been described in detail.

Combination of Lactobacillus plantarum improves the effects of tacrolimus on colitis in a mouse model

The gut microbiome has been considered to play an important role in inflammatory bowel disease (IBD). Our previous study reported that tacrolimus-altered gut microbiota elicited immunoregulatory effects in both colonic mucosa and circulation, contributing to an increased allograft survival rate in mice. Here, we aimed to observe the changes in the tacrolimus-induced microbiome in a dextran sulfate sodium (DSS)-induced colitis mouse model and explore the possibility and efficacy of combination therapy with tacrolimus and the microbiome on colitis. Mice were divided into the control, DSS, tacrolimus monotherapy and tacrolimus plus Lactobacillus plantarum 550 (Lacto)-treated groups. The body weight, stool consistency, hematochezia and survival of mice were observed daily. Total RNA from colonic mucosa was extracted and subjected to transcriptome sequencing. Cecal contents were collected and the 16S rRNA sequencing was performed to characterize the gut microbiome and the ultrahigh- performance liquid chromatography-MS/MS (UHPLC-MS/MS) was used for targeted quantification of bile acids. The results confirmed that tacrolimus significantly ameliorated DSS-induced colitis in mice. Beneficial alterations of the gut microbiome characterized by a remarkable expansion of the genus Lactobacillus were induced by tacrolimus treatment. Oral supplementation with Lacto further improved the tacrolimus-mediated suppression of body weight loss in colitis, while the survival time of mice was further prolonged and the inflammation of colonic mucosa was obviously relieved. The immune and inflammation-related signaling pathways, including IFN-γ and IFN-α response, allograft rejection, IL2 STAT5 signaling and the inflammatory response pathways, were further downregulated in the tacrolimus plus Lacto cotreatment group. Cotreatment also improved the diversity of the gut microbiome and rescued the concentration of taurochenodeoxycholic acid (TCDCA) in colitis. The latter was positively correlated with the abundance of Lactobacillus but negatively related to the disease activity index score. Overall, our results indicated that Lactobacillus plantarum promoted the therapeutic effect of tacrolimus in experimental colitis, offering a promising strategy to combine tacrolimus and Lactobacillus in the treatment of colitis patients.

Mucosal healing and inflammatory bowel disease: Therapeutic implications and new targets

Mucosal healing (MH) is vital in maintaining homeostasis within the gut and protecting against injury and infections. Multiple factors and signaling pathways contribute in a dynamic and coordinated manner to maintain intestinal homeostasis and mucosal regeneration/repair. However, when intestinal homeostasis becomes chronically disturbed and an inflammatory immune response is constitutively active due to impairment of the intestinal epithelial barrier autoimmune disease results, particularly inflammatory bowel disease (IBD). Many proteins and signaling pathways become dysregulated or impaired during these pathological conditions, with the mechanisms of regulation just beginning to be understood. Consequently, there remains a relative lack of broadly effective therapeutics that can restore MH due to the complexity of both the disease and healing processes, so tissue damage in the gastrointestinal tract of patients, even those in clinical remission, persists. With increased understanding of the molecular mechanisms of IBD and MH, tissue damage from autoimmune disease may in the future be ameliorated by developing therapeutics that enhance the body’s own healing response. In this review, we introduce the concept of mucosal healing and its relevance in IBD as well as discuss the mechanisms of IBD and potential strategies for altering these processes and inducing MH.

Lentilactobacillus kefiri SGL 13 and Andrographis paniculata alleviate dextran sulfate sodium induced colitis in mice

Introduction

Inflammatory bowel diseases (IBD) are chronic inflammatory conditions that typically involve diarrhea, abdominal pain, fatigue, and weight loss, with a dramatic impact on patients' quality of life. Standard medications are often associated with adverse side effects. Thus, alternative treatments such as probiotics are of great interest. The purpose of the present study was to evaluate the effects of oral administration of Lentilactobacillus kefiri (basonym: Lactobacillus kefiri) SGL 13 and Andrographis paniculata, namely, Paniculin 13™, on dextran sodium sulfate (DSS)- treated C57BL/6J mice.

Methods

Colitis was induced by administering 1.5% DSS in drinking water for 9 days. Forty male mice were divided into four groups, receiving PBS (control), 1.5% DSS, Paniculin 13™ and 1.5% DSS + Paniculin 13™.

Results

The results showed that body weight loss and Disease Activity Index (DAI) score were improved by Paniculin 13™. Moreover, Paniculin 13™ ameliorated DSS-induced dysbiosis, by modulating the gut microbiota composition. The gene expression of MPO, TNFα and iNOS in colon tissue was reduced and these data matched with the histological results, supporting the efficacy of Paniculin 13™ in reducing the inflammatory response. No adverse effects were associated to Paniculin 13™ administration.

Discussion

In conclusion, Paniculin 13™ could be an effective add-on approach to conventional therapies for IBD.

The role of potential probiotic strains Lactobacillus reuteri in various intestinal diseases: New roles for an old player

Lactobacillus reuteri (L. reuteri), a type of Lactobacillus spp., is a gut symbiont that can colonize many mammals. Since it was first isolated in 1962, a multitude of research has been conducted to investigate its function and unique role in different diseases as an essential probiotic. Among these, the basic functions, beneficial effects, and underlying mechanisms of L. reuteri have been noticed and understood profoundly in intestinal diseases. The origins of L. reuteri strains are diverse, with humans, rats, and piglets being the most common. With numerous L. reuteri strains playing significant roles in different intestinal diseases, DSM 17938 is the most widely used in humans, especially in children. The mechanisms by which L. reuteri improves intestinal disorders include protecting the gut barrier, suppressing inflammation and the immune response, regulating the gut microbiota and its metabolism, and inhibiting oxidative stress. While a growing body of studies focused on L. reuteri, there are still many unknowns concerning its curative effects, clinical safety, and precise mechanisms. In this review, we initially interpreted the basic functions of L. reuteri and its related metabolites. Then, we comprehensively summarized its functions in different intestinal diseases, including inflammatory bowel disease, colorectal cancer, infection-associated bowel diseases, and pediatric intestinal disorders. We also highlighted some important molecules in relation to the underlying mechanisms. In conclusion, L. reuteri has the potential to exert a beneficial impact on intestinal diseases, which should be further explored to obtain better clinical application and therapeutic effects.

Differential reinforcement of intestinal barrier function by various Lactobacillus reuteri strains in mice with DSS-induced acute colitis

AIMS

Inflammatory bowel disease is a complex, refractory disorder characterised by chronic gastrointestinal inflammation. Studies have reported that Lactobacillus reuteri alleviates gastrointestinal inflammation and strengthens the intestinal barrier. However, further biochemical and genetic studies are required to correctly understand the therapeutic potential of L. reuteri.

MATERIALS AND METHODS

This study sought to further understand the anti-colitis effect of L. reuteri isolated from faecal samples of healthy locals by focusing on biochemical (immunological, mechanical, chemical and biological barriers) and genetic studies.

KEY FINDINGS

In this study, we assessed and compared the benefits and efficacy of L. reuteri FYNDL13 and FCQHC8L in the treatment of colitis and found strain FYNDL13 to be superior to FCQHC8L in this regard. Compared with FCQHC8L, FYNDL13 was associated with more diverse and powerful regulatory pathways. Meanwhile, it encouraged butyric acid formation, upregulated antimicrobial peptide-coding gene transcription and prevented hyperimmune reactions on the intestinal periphery and within the intestine. Moreover, it enhanced the abundance of beneficial bacteria (Bifidobacterium, Akkermansia, Blautia and Oscillospira), thereby limiting the relative abundance of harmful bacteria (Bacteroides and Sutterella). Furthermore, the advantage might be attributed to metabolism- and defence system-related genomic characteristics.

SIGNIFICANCE

Taken together, our study compares and summarizes a pathway paradigm of these two L. reuteri strains in reinforcing the intestinal barrier against colitis and identifies candidate genes responsible for microbiota-immune axis balance.

Intake of Pro- and/or Prebiotics as a Promising Approach for Prevention and Treatment of Colorectal Cancer

Colorectal cancer (CRC) is the third most common type of cancer, posing a serious threat to human life. It is widely believed that dietary factors may be crucial modifiers of CRC risk, with pro-and/or prebiotics being especially promising. In this review, a synthesis of CRC prevention and treatment of strategies relying on usage of pro- and/or prebiotics supplements is given, as well as discuss mechanisms underlying the contribution of pro-and/or prebiotics to the suppression of colonic carcinogenesis. Furthermore, a framework for personalizing such supplements according to the composition of an individual's gut microbiome is suggested. Various factors including diversity of one's intestinal microflora, integrity of their intestinal barrier, and the presence of mutagenic/carcinogenic/genotoxic and beneficial compounds are known to have a prominent influence on the development of CRC; thus, clarifying the role of pro- and/or prebiotics will yield valuable insight toward optimizing interventions for enhanced patient outcomes in the future.

Prodrug Integrated Envelope on Probiotics to Enhance Target Therapy for Ulcerative Colitis

Ulcerative colitis (UC), affecting millions of patients worldwide, is associated with disorders of the gut microbiota. Probiotics-based therapy positively regulating the community structure of gut microbiota is regarded as an efficient intervention for UC. However, oral probiotics delivery is restricted by limited bioactivity, short retention time, complex pathological condition, and single therapeutic efficacy. Here, a bioengineered probiotic decorated with a multifunctional prodrug coating is constructed to ameliorate the aforementioned shortcomings. The results of UC mice induced by dextran sulfate sodium demonstrate that the intrinsic features of the fabricated coating integrate gut microbes protection, colon-targeted drug release, prolonged drug retention, and inflammation regulation. In parallel, the probiotics Lactobacillus rhamnosus GG (LGG) could regulate the composition of the gut microbiota and improve epithelial barrier function, thereby synergistically ameliorating UC. These results provide ample shreds of evidence of the therapeutic effect on UC, therefore, demonstrate a great promise as the potential therapeutic strategy for UC treatment.

Probiotics for the Management of Pediatric Gastrointestinal Disorders: Position Paper of the ESPGHAN Special Interest Group on Gut Microbiota and Modifications

BACKGROUND

Probiotics, defined as live microorganisms that, when administered in adequate amounts, confer a health benefit on the host, are widely used despite uncertainty regarding their efficacy and discordant recommendations about their use. The European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) Special Interest Group on Gut Microbiota and Modifications provides updated recommendations for the use of probiotics for the management of selected pediatric gastrointestinal disorders.

METHODS

All systematic reviews and/or meta-analyses, as well as subsequently published randomized controlled trials (RCTs) (until December 2021), that compared the use of probiotics in all delivery vehicles and formulations, at any dose, with no probiotic (ie, placebo or no treatment), were eligible for inclusion. The recommendations were formulated only if at least 2 RCTs on a similar well-defined probiotic strain were available. The modified Delphi process was used to establish consensus on the recommendations.

RESULTS

Recommendations for the use of specific probiotic strains were made for the management of acute gastroenteritis, prevention of antibiotic-associated diarrhea, nosocomial diarrhea and necrotizing enterocolitis, management of Helicobacter pylori infection, and management of functional abdominal pain disorders and infant colic.

CONCLUSIONS

Despite evidence to support the use of specific probiotics in some clinical situations, further studies confirming the effect(s) and defining the type, dose, and timing of probiotics are still often required. The use of probiotics with no documented health benefits should be discouraged.

The role of Th17 cells in inflammatory bowel disease and the research progress

Th17 cells play an important role in the abnormal immune response in inflammatory bowel disease (IBD) and are involved in the development and progression of inflammation and fibrosis. An increasing amount of data has shown that gut microbes are important parts of intestinal immunity and regulators of Th17 cellular immunity. Th17 cell differentiation is regulated by intestinal bacteria and cytokines, and Th17 cells regulate the intestinal mucosal immune microenvironment by secreting cytokines, such as IL-17, IL-21, and IL-26. Solid evidence showed that, regarding the treatment of IBD by targeting Th17 cells, the therapeutic effect of different biological agents varies greatly. Fecal bacteria transplantation (FMT) in the treatment of IBD has been a popular research topic in recent years and is safe and effective with few side effects. To further understand the role of Th17 cells in the progression of IBD and associated therapeutic prospects, this review will discuss the progress of related research on Th17 cells in IBD by focusing on the interaction and immune regulation between Th17 cells and gut microbiota.

Evaluation of microbial and vancomycin treatments in ulcerative colitis in murine models

BACKGROUND

Despite the number of available therapies for ulcerative colitis (UC), severe side effects and high cost has limited their clinical application. Thus, finding new alternative strategies with minimal side effects is inevitable. Therefore, this study aimed to compare the effectiveness of different therapeutic approaches in DSS-induced colitis.

METHODS

Firstly, we designed oral bio-therapeutic products, Live Bacterial Products (LBP), which include a mixture of fecal bacteria strains isolated from healthy mice and prepared by microencapsulation and freeze-dried techniques. Then we investigated the efficiency of 7 days of freeze-dried FMT, LBP, and vancomycin treatments in DSS-induced colitis. Secondly, we compared the effect of 15 days of microbial therapies (freeze-dried powder of FMT and LBP microcapsules) and seven days of oral vancomycin on the severity of colitis in mice. Furthermore, the levels of IL-1β and TNF-α were measured in serum by ELISA, and the fecal microbiota diversity was analyzed by high-throughput sequencing for all mice groups.

RESULTS

After seven days of treatments, our results indicated that oral vancomycin reduced the severity of DSS-induced colitis in mice, where weight gain and a decrease in IL-1 β and TNF-α levels were observed in the vancomycin group compared with other treatment groups. While after two weeks of treatment, the LBP microcapsules were able to reduce the severity of colitis. And at the end of the treatment period, weight gain and a decrease in the DAI scores and the levels of IL-1β and TNF-α were noted in the LBP treatment group compared to other treatment groups. By high-throughput sequencing of the 16S rRNA gene, our results showed that while the microcapsules LBP treatment increased the fecal microbial diversity, after vancomycin therapy, most of the fecal microbiota genera and operational taxonomic units (OTUs) were depleted.

CONCLUSION

Our results concluded that treatment duration and preparation methods affect the microbial therapies' efficiency in UC. Furthermore, this study highlighted the negative consequences of oral vancomycin administration on gut health that should be known before using this medication.

Probiotics and gastrointestinal diseases

During the past decades, scientists have discovered the intimate role of the gut microbiome in human health, and since then, several papers have been published to investigate if the use of biotics (probiotics, prebiotics, synbiotics, and postbiotics) may have a beneficial impact on human health both in treatment and prevention. We now ask ourselves whether we have reached the finish line or just a new starting point, as the evidence supporting the use of biotics in several conditions still needs a lot of work. Many questions remain unanswered today because the evidence differs depending on the indication, used strain, and amount and duration of administration. Herein we will summarize the evidence on probiotics in some gastrointestinal diseases such as infantile colic, functional abdominal pain disorders, celiac disease, acute gastroenteritis, inflammatory bowel disease, and Helicobacter pylori infection.

Using probiotics in paediatric populations

This statement defines probiotics and reviews the most recent literature on their use in paediatrics. Many studies have examined the potential benefit of probiotics, but significant variation in the strains and doses of probiotics used, the patient populations studied, and in study design, have led to heterogeneous results. Present evidence suggests that probiotics can decrease mortality and lower incidence of necrotizing enterocolitis in preterm and low birth weight neonates. Probiotics may also be beneficial in reducing feeding intolerance. In infants, probiotics may be considered to reduce symptoms of colic. In older children, probiotics can be considered to prevent antibiotic-associated diarrhea and Clostridium difficile -associated diarrhea. Probiotic supplements used in conjunction with standard therapy can help with Helicobacter pylori eradication and decrease the side effects of treatment. Lactobacillus species can be considered to treat irritable bowel syndrome. Probiotics can also be considered to help prevent atopic dermatitis and eczema. To optimize paediatric policy and practice, large, quality studies are needed to determine what types and combinations of probiotics are most efficacious.

L’utilisation des probiotiques dans la population pédiatrique

Le présent document de principes définit les probiotiques et fournit une analyse des publications scientifiques les plus récentes sur leur utilisation en pédiatrie. De nombreuses études ont évalué les avantages potentiels des probiotiques, mais en raison des variations importantes dans les souches et les doses utilisées, des populations de patients étudiées et des méthodologies privilégiées, les résultats sont hétérogènes. Selon les données probantes à jour, les probiotiques peuvent réduire le taux de mortalité et l’incidence d’entérocolite nécrosante chez les nouveau-nés prématurés et de petit poids à la naissance. Ils peuvent également être bénéfiques pour réduire l’intolérance alimentaire. Chez les nourrissons, on peut envisager de les utiliser pour limiter les symptômes de coliques, et chez les enfants plus âgés, pour prévenir la diarrhée associée aux antibiotiques ou au Clostridium difficile . Les suppléments de probiotiques utilisés conjointement avec un traitement standard peuvent contribuer à éradiquer l’Helicobacter pylori et à atténuer les effets secondaires du traitement. On peut envisager d’utiliser des espèces de Lactobacillus pour traiter le syndrome du côlon irritable ou de recourir à des probiotiques pour contribuer à prévenir la dermatite atopique et l’eczéma. Afin d’optimiser les politiques et les pratiques en pédiatrie, de vastes études de qualité devront être réalisées pour déterminer les types et les combinaisons de probiotiques les plus efficaces.

Interaction between gut microbiota and immune checkpoint inhibitor-related colitis

Immune checkpoint inhibitors (ICIs) have become a promising therapeutic strategy for malignant tumors, improving patient prognosis, along with a spectrum of immune-related adverse events (irAEs), including gastrointestinal toxicity, ICI-related colitis (IRC), and diarrhea. The gut microbiota has been suggested as an important regulator in the pathogenesis of IRC, and microbiota modulations like probiotics and fecal microbiota transplantation have been explored to treat the disease. This review discusses the interaction between the gut microbiota and IRC, focusing on the potential pathogenic mechanisms and promising interventions.

The Therapeutic Role of Short-Chain Fatty Acids Mediated Very Low-Calorie Ketogenic Diet-Gut Microbiota Relationships in Paediatric Inflammatory Bowel Diseases

The very low-calorie ketogenic diet (VLCKD) has been recognized as a promising dietary regimen for the treatment of several diseases. Short-chain fatty acids (SCFAs) produced by anaerobic bacterial fermentation of indigestible dietary fibre in the gut have potential value for their underlying epigenetic role in the treatment of obesity and asthma-related inflammation through mediating the relationships between VLCKD and the infant gut microbiota. However, it is still unclear how VLCKD might influence gut microbiota composition in children, and how SCFAs could play a role in the treatment of inflammatory bowel disease (IBD). To overcome this knowledge gap, this review aims to investigate the role of SCFAs as key epigenetic metabolites that mediate VLCKD-gut microbiota relationships in children, and their therapeutic potential in IBD.

Gut Microbiota Dynamics in Relation to Long-COVID-19 Syndrome: Role of Probiotics to Combat Psychiatric Complications

Increasing numbers of patients who recover from COVID-19 report lasting symptoms, such as fatigue, muscle weakness, dementia, and insomnia, known collectively as post-acute COVID syndrome or long COVID. These lasting symptoms have been examined in different studies and found to influence multiple organs, sometimes resulting in life-threating conditions. In this review, these symptoms are discussed in connection to the COVID-19 and long-COVID-19 immune changes, highlighting oral and psychiatric health, as this work focuses on the gut microbiota’s link to long-COVID-19 manifestations in the liver, heart, kidney, brain, and spleen. A model of this is presented to show the biological and clinical implications of gut microbiota in SARS-CoV-2 infection and how they could possibly affect the therapeutic aspects of the disease. Probiotics can support the body’s systems in fighting viral infections. This review focuses on current knowledge about the use of probiotics as adjuvant therapies for COVID-19 patients that might help to prevent long-COVID-19 complications.

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

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

Gut bacteria, bacteriophages, and probiotics: Tripartite mutualism to quench the SARS-CoV2 storm

Patients with SARS-CoV-2 infection, exhibit various clinical manifestations and severity including respiratory and enteric involvements. One of the main reasons for death among covid-19 patients is excessive immune responses directed toward cytokine storm with a low chance of recovery. Since the balanced gut microbiota could prepare health benefits by protecting against pathogens and regulating immune homeostasis, dysbiosis or disruption of gut microbiota could promote severe complications including autoimmune disorders; we surveyed the association between the imbalanced gut bacteria and the development of cytokine storm among COVID-19 patients, also the impact of probiotics and bacteriophages on the gut bacteria community to alleviate cytokine storm in COVID-19 patients. In present review, we will scrutinize the mechanism of immunological signaling pathways which may trigger a cytokine storm in SARS-CoV2 infections. Moreover, we are explaining in detail the possible immunological signaling pathway-directing by the gut bacterial community. Consequently, the specific manipulation of gut bacteria by using probiotics and bacteriophages for alleviation of the cytokine storm will be investigated. The tripartite mutualistic cooperation of gut bacteria, probiotics, and phages as a candidate prophylactic or therapeutic approach in SARS-CoV-2 cytokine storm episodes will be discussed at last.

Microbiome and paediatric gut diseases

In the human gut resides a vast community of microorganisms which perform critical functions for the maintenance of whole body homeostasis. Changes in the composition and function of this community, termed microbiome, are believed to provoke disease onset, including non-communicable diseases. In this review, we debate the current evidence on the role of the gut microbiome in the pathogenesis, outcomes and management of paediatric gut disease. We conclude that even though the gut microbiome is altered in paediatric inflammatory bowel disease, coeliac disease, intestinal failure, necrotising enterocolitis and irritable bowel syndrome, there are currently very few implications for unravelling disease pathogenesis or guiding clinical practice. In the future, the gut microbiome may aid in disease differential diagnosis and prediction of clinical outcomes, and comprise a target for therapeutic interventions.

The gut microbiota - a vehicle for the prevention and treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) arises principally against a background of cirrhosis and these two diseases are responsible globally for over 2 million deaths a year. There are few treatment options for liver cirrhosis and HCC, so it is vital to arrest these pathologies early in their development. To do so, we propose dietary and therapeutic solutions that involve the gut microbiota and its consequences. Integrated dietary, environmental and intrinsic signals result in a bidirectional connection between the liver and the gut with its microbiota, known as the gut-liver axis. Numerous lifestyle factors can result in dysbiosis with a change in the functional composition and metabolic activity of the microbiota. A panoply of metabolites can be produced by the microbiota, including ethanol, secondary bile acids, trimethylamine, indole, quinolone, phenazine and their derivatives and the quorum sensor acyl homoserine lactones that may contribute to HCC but have yet to be fully investigated. Gram-negative bacteria can activate the pattern recognition receptor toll-like receptor 4 (TLR4) in the liver leading to nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling, which can contribute to HCC initiation and progression. The goal in preventing HCC should be to ensure a healthy gut microbiota using probiotic supplements containing beneficial bacteria and prebiotic plant fibers such as oligosaccharides that stimulate their growth. The clinical development of TLR4 antagonists is urgently needed to counteract the pathological effects of dysbiosis on the liver and other organs. Further nutrigenomic studies are required to understand better how the diet influences the gut microbiota and its adverse effects on the liver.

Lactobacillus rhamnosus sepsis, endocarditis and septic emboli in a patient with ulcerative colitis taking probiotics

A man in his 60s presented to the emergency room with fever and fatigue after a 2.5-month course of corticosteroids. His medical history was significant for bioprosthetic aortic valve replacement and moderately severe ulcerative colitis treated with balsalazide and daily lactobacillus-containing probiotics. Initial investigations revealed Lactobacillus rhamnosus bacteraemia without complication. Four days after hospital discharge, the patient experienced acute-onset right-sided paraesthesia and lower-limb paresis. On return to the emergency room, MRI of the brain demonstrated innumerable ring-enhancing lesions with haemorrhagic transformation. Transoesophageal echocardiogram revealed a small mobile density on the bioprosthetic aortic valve, raising the suspicion for L. rhamnosus infective endocarditis with secondary septic emboli to the brain. The patient was subsequently treated with intravenous gentamycin and ampicillin, with transition to indefinite oral amoxicillin suppressive therapy. The current case highlights the potential risk of lactobacilli translocation in an immunosuppressed patient with ulcerative colitis taking probiotics.

Nutrition and Supplementation in Ulcerative Colitis

Ulcerative colitis (UC) belongs to the group of inflammatory bowel diseases (IBD). UC is an incurable, diffuse, and chronic inflammatory process of the colonic mucosa with alternating periods of exacerbation and remission. This review aimed to analyze the scientific research conducted to date to determine what impact different nutritional plans and dietary supplements may have on the course of UC. The latest 98 articles about nutrition and supplementation in ulcerative colitis were used to prepare the work. Certain components in food can greatly influence the course of UC, inducing changes in the composition and function of the gut microbiome. This activity may be an important part of therapy for people with IBD. The Mediterranean diet has shown the most promising results in the treatment of patients with UC due to its high content of biologically active foods. Patients with UC may benefit from the UC Exclusion Diet (UCED); however, it is a new nutritional plan that requires further research. Patents frequently resort to unconventional diets, which, because of their frequent elimination of nutrient-rich foods, can worsen the health and nutritional status of those who follow them. The benefits of omega-3 fatty acids and probiotics supplementation may have additional therapeutic effects; however, the evidence is not unequivocal.

Lactobacillus plantarum strains attenuated DSS-induced colitis in mice by modulating the gut microbiota and immune response

Gut microbiota has become a new therapeutic target in the treatment of inflammatory Bowel Disease (IBD). Probiotics are known for their beneficial effects and have shown good efficacy in the clinical treatment of IBD and animal models of colitis. However, how these probiotics contribute to the amelioration of IBD is largely unknown. In the current study, the DSS-induced mouse colitis model was treated with oral administration of Lactobacillus plantarum strains to investigate their effects on colitis. The results indicated that the L. plantarum strains improved dysbiosis and enhanced the abundance of beneficial bacteria related to short-chain fatty acids (SCFAs) production. Moreover, L. plantarum strains decreased the level of pro-inflammatory cytokines, i.e., IL-17A, IL-17F, IL-6, IL-22, and TNF-α and increased the level of anti-inflammatory cytokines, i.e., TGF-β, IL-10. Our result suggests that L. plantarum strains possess probiotic effects and can ameliorate DSS colitis in mice by modulating the resident gut microbiota and immune response.

Efficacy of Probiotics-Based Interventions as Therapy for Inflammatory Bowel Disease: A Recent Update

Probiotics such as Lactobacillus spp. play an important role in human health as they embark beneficial effect on the human gastrointestinal microflora composition and immune system. Dysbiosis in the gastrointestinal microbial composition has been identified as a major contributor to chronic inflammatory conditions, such as inflammatory bowel disease (IBD). Higher prevalence of IBD is often recorded in most of the developed Western countries, but recent data has shown an increase in previously regarded as lower risk regions, such as Japan, Malaysia, Singapore, and India. Although the IBD etiology remains a subject of speculation, the disease is likely to have developed because of interaction between extrinsic environmental elements; the host’s immune system, and the gut microbial composition. Compared to conventional treatments, probiotics and probiotic-based interventions including the introduction of specific prebiotics, symbiotic and postbiotic products had been demonstrated as more promising therapeutic measures. The present review discusses the association between gut dysbiosis, the pathogenesis of IBD, and risk factors leading to gut dysbiosis. In addition, it discusses recent studies focused on the alteration of the gastrointestinal microbiome as an effective therapy for IBD. The impact of the COVID-19 pandemic and other viral infections on IBD are also discussed in this review. Clinical and animal-based studies have shown that probiotic-based therapies can restore the gastrointestinal microbiota balance and reduce gut inflammations. Therefore, this review also assesses the status quo of these microbial-based therapies for the treatment of IBD. A better understanding of the mechanisms of their actions on modulating altered gut microbiota is required to enhance the effectiveness of the IBD therapeutics.

Reuterin in the healthy gut microbiome suppresses colorectal cancer growth through altering redox balance

Microbial dysbiosis is a colorectal cancer (CRC) hallmark and contributes to inflammation, tumor growth, and therapy response. Gut microbes signal via metabolites, but how the metabolites impact CRC is largely unknown. We interrogated fecal metabolites associated with mouse models of colon tumorigenesis with varying mutational load. We find that microbial metabolites from healthy mice or humans are growth-repressive, and this response is attenuated in mice and patients with CRC. Microbial profiling reveals that Lactobacillus reuteri and its metabolite, reuterin, are downregulated in mouse and human CRC. Reuterin alters redox balance, and reduces proliferation and survival in colon cancer cells. Reuterin induces selective protein oxidation and inhibits ribosomal biogenesis and protein translation. Exogenous Lactobacillus reuteri restricts colon tumor growth, increases tumor reactive oxygen species, and decreases protein translation in vivo. Our findings indicate that a healthy microbiome and specifically, Lactobacillus reuteri, is protective against CRC through microbial metabolite exchange.

Construction of the Enterococcal Strain Expressing Immunogenic Fragment of SARS-Cov-2 Virus

Contemporary SARS-Cov-2 pandemic, besides its dramatic global influence on the human race including health care systems, economies, and political decisions, opened a window for the global experiment with human vaccination employing novel injectable vaccines providing predominantly specific IgG response with little knowledge of their impact on the mucosal immunity. However, it is widely accepted that protection against the pathogens at the gates of the infection - on mucosal surfaces—predominantly rely on an IgA response. Some genetically modified bacteria, including probiotics, represent attractive vehicles for oral or nasal mucosal delivery of therapeutic molecules. Probiotic-based vaccines for mucous membranes are easy to produce in large quantities; they have low cost, provide quite a long T-cell memory, and gut IgA response to oral vaccines is highly synchronized and strongly oligoclonal. Here we present a study demonstrating construction of the novel SARS-Cov-2 vaccine candidate employing the gene fragment of S1 SARS-Cov-2 gene. This DNA fragment was inserted in frame into major pili protein gene with d2 domain of enterococcal operon encoding for pili. The DNA sequencing proved the presence of the insert in enterococcal genome. RNA transcription, immunoprecipitation, and immune electron microscopy with human sera obtained from the SARS-Cov-2 patients demonstrated expression of SARS-Cov-2 antigens in bacteria. Taken together the data obtained allowed considering this genetically modified probiotic strain as an interesting candidate for vaccine against SARS-Cov-2.

Construction of the Enterococcal Strain Expressing Immunogenic Fragment of SARS-Cov-2 Virus

Contemporary SARS-Cov-2 pandemic, besides its dramatic global influence on the human race including health care systems, economies, and political decisions, opened a window for the global experiment with human vaccination employing novel injectable vaccines providing predominantly specific IgG response with little knowledge of their impact on the mucosal immunity. However, it is widely accepted that protection against the pathogens at the gates of the infection - on mucosal surfaces—predominantly rely on an IgA response. Some genetically modified bacteria, including probiotics, represent attractive vehicles for oral or nasal mucosal delivery of therapeutic molecules. Probiotic-based vaccines for mucous membranes are easy to produce in large quantities; they have low cost, provide quite a long T-cell memory, and gut IgA response to oral vaccines is highly synchronized and strongly oligoclonal. Here we present a study demonstrating construction of the novel SARS-Cov-2 vaccine candidate employing the gene fragment of S1 SARS-Cov-2 gene. This DNA fragment was inserted in frame into major pili protein gene with d2 domain of enterococcal operon encoding for pili. The DNA sequencing proved the presence of the insert in enterococcal genome. RNA transcription, immunoprecipitation, and immune electron microscopy with human sera obtained from the SARS-Cov-2 patients demonstrated expression of SARS-Cov-2 antigens in bacteria. Taken together the data obtained allowed considering this genetically modified probiotic strain as an interesting candidate for vaccine against SARS-Cov-2.

Gut-lung cross talk in COVID-19 pathology and fatality rate

Coronavirus disease 2019 (COVID-19) is the leading pandemic facing the world in 2019/2020; it is caused by a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which necessitates clear understanding of the infectious agent. The virus manifests aggressive behavior with severe clinical presentation and high mortality rate, especially among the elderly and patients living with chronic diseases. In the recent years, the role of gut microbiota, in health and disease, has been progressively studied and highlighted. It is through gut microbiota-organ bidirectional pathways, such as gut-brain axis, gut-liver axis, and gut-lung axis, that the role of gut microbiota in prompting lung disease, among other diseases, has been proposed and accepted. It is also known that respiratory viral infections, such as COVID-19, induce alterations in the gut microbiota, which can influence immunity. Based on the fact that gut microbiota diversity is decreased in old age and in patients with certain chronic diseases, which constitute two of the primary fatality groups in COVID-19 infections, it can be assumed that the gut microbiota may play a role in COVID-19 pathology and fatality rate. Improving gut microbiota diversity through personalized nutrition and supplementation with prebiotics/probiotics will mend the immunity of the body and hence could be one of the prophylactic strategies by which the impact of COVID-19 can be minimized in the elderly and immunocompromised patients. In this chapter, the role of dysbiosis in COVID-19 will be clarified and the possibility of using co-supplementation of personalized prebiotics/probiotics with current therapies will be discussed.

The Communication Between Intestinal Microbiota and Ulcerative Colitis: An Exploration of Pathogenesis, Animal Models, and Potential Therapeutic Strategies

Ulcerative Colitis (UC) is a chronic inflammatory bowel disease. The prolonged course of UC and the lack of effective treatment management make it difficult to cure, affecting the health and life safety of patients. Although UC has received more attention, the etiology and pathogenesis of UC are still unclear. Therefore, it is urgent to establish an updated and comprehensive understanding of UC and explore effective treatment strategies. Notably, sufficient evidence shows that the intestinal microbiota plays an important role in the pathogenesis of UC, and the treating method aimed at improving the balance of the intestinal microbiota exhibits a therapeutic potential for UC. This article reviews the relationship between the genetic, immunological and microbial risk factors with UC. At the same time, the UC animal models related to intestinal microbiota dysbiosis induced by chemical drugs were evaluated. Finally, the potential value of the therapeutic strategies for restoring intestinal microbial homeostasis and treating UC were also investigated. Comprehensively, this study may help to carry out preclinical research, treatment theory and methods, and health management strategy of UC, and provide some theoretical basis for TCM in the treatment of UC.

Effect of infant formula supplemented with prebiotics and probiotics on incidence of respiratory tract infections: A systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Previous investigations have proposed that the consumption of infant formula supplemented with prebiotics, probiotics and synbiotics (PRO-formula) may have protective impacts on respiratory tract infections (RTIs). Nevertheless, the findings of studies are contradictory. This meta-analysis aimed to explore the influence of PRO-formula on RTIs in infants by pooling randomized controlled trials (RCTs).

METHODS

To obtain eligible RCTs, Scopus and PubMed databases were systematically searched from their inception to November 2020. A random-effects model was applied to pool the relative risks (RR) and corresponding 95% confidence intervals (CI) for RTIs following consumption of PRO-formula.

RESULTS

A total of 15 RCTs, with a total sample size of 3805 participants (1957 for intervention and 1848 for placebo), were included in the present meta-analysis. In the overall analysis, in comparison to placebo, consumption of PRO-formula had a significant protective impact against RTIs (RR = 0.89, 95%CI: 0.82-0.97) in infants, with a remarkable evidence of heterogeneity across studies (I2 = 61.4%, P < 0.001). In the meta-regression analysis, the effect of PRO-formula on RTIs was not modified by the follow-up duration. No evidence for publication bias was detected.

CONCLUSIONS

Administration of PRO-formula may be a potential approach for the prevention of respiratory tract infections in infants.

Therapeutic Advances in Gut Microbiome Modulation in Patients with Inflammatory Bowel Disease from Pediatrics to Adulthood

There is mounting evidence that the gut microbiota plays an important role in the pathogenesis of inflammatory bowel disease (IBD). For the past decade, high throughput sequencing-based gut microbiome research has identified characteristic shifts in the composition of the intestinal microbiota in patients with IBD, suggesting that IBD results from alterations in the interactions between intestinal microbes and the host’s mucosal immune system. These studies have been the impetus for the development of new therapeutic approaches targeting the gut microbiome, such as nutritional therapies, probiotics, fecal microbiota transplant and beneficial metabolic derivatives. Innovative technologies can further our understanding of the role the microbiome plays as well as help to evaluate how the different approaches in microbiome modulation impact clinical responses in adult and pediatric patients. In this review, we highlight important microbiome studies in patients with IBD and their response to different microbiome modulation therapies, and describe the differences in therapeutic response between pediatric and adult patient cohorts.

Limosilactobacillus reuteri ATCC 6475 metabolites upregulate the serotonin transporter in the intestinal epithelium

The serotonin transporter (SERT) readily takes up serotonin (5-HT), thereby regulating the availability of 5-HT within the intestine. In the absence of SERT, 5-HT remains in the interstitial space and has the potential to aberrantly activate the many 5-HT receptors distributed on the epithelium, immune cells and enteric neurons. Perturbation of SERT is common in many gastrointestinal disorders as well as mouse models of colitis. Select commensal microbes regulate intestinal SERT levels, but the mechanism of this regulation is poorly understood. Additionally, ethanol upregulates SERT in the brain and dendritic cells, but its effects in the intestine have never been examined. We report that the intestinal commensal microbe Limosilactobacillus (previously classified as Lactobacillus) reuteri ATCC PTA 6475 secretes 83.4 mM ethanol. Consistent with the activity of L. reuteri alcohol dehydrogenases, we found that L. reuteri tolerated various levels of ethanol. Application of L. reuteri conditioned media or exogenous ethanol to human colonic T84 cells was found to upregulate SERT at the level of mRNA. A 4-(4-(dimethylamino) phenyl)-1-methylpyridinium (APP+) uptake assay confirmed the functional activity of SERT. These findings were mirrored in mouse colonic organoids, where L. reuteri metabolites and ethanol were found to upregulate SERT at the apical membrane. Finally, in a trinitrobenzene sulphonic acid model of acute colitis, we observed that mice treated with L. reuteri maintained SERT at the colon membrane compared with mice receiving phosphate buffered saline vehicle control. These data suggest that L. reuteri metabolites, including ethanol, can upregulate SERT and may be beneficial for maintaining intestinal homeostasis with respect to serotonin signalling.