Microbiota-Immune Interactions in Ulcerative Colitis and Colitis Associated Cancer and Emerging Microbiota-Based Therapies

Mixed species biofilm: Structure, challenge and its intricate involvement in hospital associated infections

Hospital associated infections or healthcare associated infections (HAIs) are a major threat to healthcare and medical management, mostly because of their recalcitrant nature. The primary cause of these HAIs is bacterial associations, especially the interspecies interactions. In interspecies interactions, more than one species co-exists in a common platform of extracellular polymeric substances (EPS), establishing a strong interspecies crosstalk and thereby lead to the formation of mixed species biofilms. In this process, the internal microenvironment and the surrounding EPS matrix of the biofilms ensure the protection of the microorganisms and allow them to survive under antagonistic conditions. The communications between the biofilm members as well as the interactions between the bacterial cells and the matrix polymers, also aid in the rigidity of the biofilm structure and allow the microorganisms to evade both the host immune response and a wide range of anti-microbials. Therefore, to design a treatment protocol for HAIs is difficult and it has become a growing point of concern. This review therefore first aims to discuss the role of microenvironment, molecular structure, cell-cell communication, and metabolism of mixed species biofilms in manifestation of HAIs. In addition, we discuss the electrochemical properties of mixed-species biofilms and their mechanism in developing drug resistance. Then we focus on the most dreaded bacterial HAI including oral and gut multi-species infections, catheter-associated urinary tract infections, surgical site infections, and ventilator-associated pneumonia. Further, we highlight the challenges to eradication of the mixed species biofilms and the current and prospective future strategies for the treatment of mixed species-associated HAI. Together, the review presents a comprehensive understanding of mixed species biofilm-mediated infections in clinical scenario, and summarizes the current challenge and prospect of therapeutic strategies against HAI.

Artificial intelligence and machine learning technologies in ulcerative colitis

Interest in artificial intelligence (AI) applications for ulcerative colitis (UC) has grown tremendously in recent years. In the past 5 years, there have been over 80 studies focused on machine learning (ML) tools to address a wide range of clinical problems in UC, including diagnosis, prognosis, identification of new UC biomarkers, monitoring of disease activity, and prediction of complications. AI classifiers such as random forest, support vector machines, neural networks, and logistic regression models have been used to model UC clinical outcomes using molecular (transcriptomic) and clinical (electronic health record and laboratory) datasets with relatively high performance (accuracy, sensitivity, and specificity). Application of ML algorithms such as computer vision, guided image filtering, and convolutional neural networks have also been utilized to analyze large and high-dimensional imaging datasets such as endoscopic, histologic, and radiological images for UC diagnosis and prediction of complications (post-surgical complications, colorectal cancer). Incorporation of these ML tools to guide and optimize UC clinical practice is promising but will require large, high-quality validation studies that overcome the risk of bias as well as consider cost-effectiveness compared to standard of care.

Therapeutic effects and mechanisms of isoxanthohumol on DSS-induced colitis: regulating T cell development, restoring gut microbiota, and improving metabolic disorders

Ulcerative colitis (UC) is a severe hazard to human health. Since pathogenesis of UC is still unclear, current therapy for UC treatment is far from optimal. Isoxanthohumol (IXN), a prenylflavonoid from hops and beer, possesses anti-microbial, anti-oxidant, anti-inflammatory, and anti-angiogenic properties. However, the potential effects of IXN on the alleviation of colitis and the action of the mechanism is rarely studied. Here, we found that administration of IXN (60 mg/kg/day, gavage) significantly attenuated dextran sodium sulfate (DSS)-induced colitis, evidenced by reduced DAI scores and histological improvements, as well as suppressed the pro-inflammatory Th17/Th1 cells but promoted the anti-inflammatory Treg cells. Mechanically, oral IXN regulated T cell development, including inhibiting CD4+ T cell proliferation, promoting apoptosis, and regulating Treg/Th17 balance. Furthermore, IXN relieved colitis by restoring gut microbiota disorder and increasing gut microbiota diversity, which was manifested by maintaining the ratio of Firmicutes/Bacteroidetes balance, promoting abundance of Bacteroidetes and Ruminococcus, and suppressing abundance of proteobacteria. At the same time, the untargeted metabolic analysis of serum samples showed that IXN promoted the upregulation of D-( +)-mannose and L-threonine and regulated pyruvate metabolic pathway. Collectively, our findings revealed that IXN could be applied as a functional food component and served as a therapeutic agent for the treatment of UC.

The role of gut microbiota and probiotics in preventing, treating, and boosting the immune system in colorectal cancer

The gut microbiome plays a significant role in developing colorectal cancer (CRC). The gut microbiome usually acts as a protective barrier against harmful pathogens and infections in the intestine, while also regulating inflammation by affecting the human immune system. The gut microbiota and probiotics play a role not only in intestinal inflammation associated with tumor formation but also in regulating anti-cancer immune response. As a result, they associated with tumor progression and the effectiveness of anti-cancer therapies. Research indicates that gut microbiota and probiotics can be used as biomarkers to predict the impact of immunotherapy and enhance its efficacy in treating CRC by regulating it. This review examines the importance of gut microbiota and probiotics in the development and progression of CRC, as well as their synergistic impact on anti-cancer treatments.

Panaxynol improves crypt and mucosal architecture, suppresses colitis-enriched microbes, and alters the immune response to mitigate colitis

Ulcerative colitis (UC) is an idiopathic inflammatory disease of the large intestine, which impacts millions worldwide. Current interventions aimed at treating UC symptoms can have off-target effects, invoking the need for alternatives that may provide similar benefits with less unintended consequences. This study builds on our initial data, which showed that panaxynol-a novel, potent, bioavailable compound found in American ginseng-can suppress disease severity in murine colitis. Here we explore the underlying mechanisms by which panaxynol improves both chronic and acute murine colitis. Fourteen-week-old C57BL/6 female mice were either given three rounds of dextran sulfate sodium (DSS) in drinking water to induce chronic colitis or one round to induce acute colitis. Vehicle or panaxynol (2.5 mg/kg) was administered via oral gavage three times per week for the study duration. Consistent with our previous findings, panaxynol significantly (P < 0.05) improved the disease activity index and endoscopic scores in both models. Using the acute model to examine potential mechanisms, we show that panaxynol significantly (P < 0.05) reduced DSS-induced crypt distortion, goblet cell loss, and mucus loss in the colon. 16S Sequencing revealed panaxynol altered microbial composition to suppress colitis-enriched genera (i.e., Enterococcus, Eubacterium, and Ruminococcus). In addition, panaxynol significantly (P < 0.05) suppressed macrophages and induced regulatory T-cells in the colonic lamina propria. The beneficial effects of panaxynol on mucosal and crypt architecture, combined with its microbial and immune-mediated effects, provide insight into the mechanisms by which panaxynol suppresses murine colitis. Overall, this data is promising for the use of panaxynol to improve colitis in the clinic.NEW & NOTEWORTHY In the current study, we report that panaxynol ameliorates chemically induced murine colitis by improving colonic crypt and mucosal architecture, suppressing colitis-enriched microbes, reducing macrophages, and promoting the differentiation of regulatory T-cells in the colonic lamina propria. This study suggests that this novel natural compound may serve as a safe and effective treatment option for colitis patients.

Plant-derived vesicle-like nanoparticles: A new tool for inflammatory bowel disease and colitis-associated cancer treatment

Long-term use of conventional drugs to treat inflammatory bowel diseases (IBD) and colitis-associated cancer (CAC) has an adverse impact on the human immune system and easily leads to drug resistance, highlighting the urgent need to develop novel biotherapeutic tools with improved activity and limited side effects. Numerous products derived from plant sources have been shown to exert antibacterial, anti-inflammatory and antioxidative stress effects. Plant-derived vesicle-like nanoparticles (PDVLNs) are natural nanocarriers containing lipids, protein, DNA and microRNA (miRNA) with the ability to enter mammalian cells and regulate cellular activity. PDVLNs have significant potential in immunomodulation of macrophages, along with regulation of intestinal microorganisms and friendly antioxidant activity, as well as overcoming drug resistance. PDVLNs have utility as effective drug carriers and potential modification, with improved drug stability. Since immune function, intestinal microorganisms, and antioxidative stress are commonly targeted key phenomena in the treatment of IBD and CAC, PDVLNs offer a novel therapeutic tool. This review provides a summary of the latest advances in research on the sources and extraction methods, applications and mechanisms in IBD and CAC therapy, overcoming drug resistance, safety, stability, and clinical application of PDVLNs. Furthermore, the challenges and prospects of PDVLN-based treatment of IBD and CAC are systematically discussed.

Effects of acupuncture and moxibustion on ulcerative colitis: An overview of systematic reviews

Ulcerative colitis (UC) is a gastrointestinal disease with an unknown etiology that severely affects patients' quality of life. Acupuncture and moxibustion therapies are effective in the treatment of UC, but existing systematic reviews (SRs) and meta-analyses (MAs) on this subject have variable methodological and outcome quality. Therefore, this study aimed to summarize and evaluate the evidence of existing SRs and MAs to provide more reliable evidence for clinical practice. Data were extracted from seven databases through systematic search and evaluated in terms of the methodological quality, reporting quality, risk of bias, and quality of evidence using the AMSTAR-2, PRISMA, ROBIS, and GRADE systems, respectively. Ten studies were finally included, and all of them showed many problems with the overall design and quality of outcomes. Because of the lack of high-quality evidence to support the findings from the existing studies, we should take this conclusion with caution and strictly implement the registration, design, and implementation of trials based on evidence to provide high-quality results in future studies.

Functional contribution of the intestinal microbiome in autism spectrum disorder, attention deficit hyperactivity disorder, and Rett syndrome: a systematic review of pediatric and adult studies

Introduction

Critical phases of neurodevelopment and gut microbiota diversification occur in early life and both processes are impacted by genetic and environmental factors. Recent studies have shown the presence of gut microbiota alterations in neurodevelopmental disorders. Here we performed a systematic review of alterations of the intestinal microbiota composition and function in pediatric and adult patients affected by autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), and Rett syndrome (RETT).

Methods

We searched selected keywords in the online databases of PubMed, Cochrane, and OVID (January 1980 to December 2021) with secondary review of references of eligible articles. Two reviewers independently performed critical appraisals on the included articles using the Critical Appraisal Skills Program for each study design.

Results

Our systematic review identified 18, 7, and 3 original articles describing intestinal microbiota profiles in ASD, ADHD, and RETT, respectively. Decreased Firmicutes and increased Bacteroidetes were observed in the gut microbiota of individuals affected by ASD and ADHD. Proinflammatory cytokines, short-chain fatty acids and neurotransmitter levels were altered in ASD and RETT. Constipation and visceral pain were related to changes in the gut microbiota in patients affected by ASD and RETT. Hyperactivity and impulsivity were negatively correlated with Faecalibacterium (phylum Firmicutes) and positively correlated with Bacteroides sp. (phylum Bacteroidetes) in ADHD subjects. Five studies explored microbiota-or diet-targeted interventions in ASD and ADHD. Probiotic treatments with Lactobacillus sp. and fecal microbiota transplantation from healthy donors reduced constipation and ameliorated ASD symptoms in affected children. Perinatal administration of Lactobacillus sp. prevented the onset of Asperger and ADHD symptoms in adolescence. Micronutrient supplementation improved disease symptomatology in ADHD without causing significant changes in microbiota communities' composition.

Discussion

Several discrepancies were found among the included studies, primarily due to sample size, variations in dietary practices, and a high prevalence of functional gastrointestinal symptoms. Further studies employing longitudinal study designs, larger sample sizes and multi-omics technologies are warranted to identify the functional contribution of the intestinal microbiota in developmental trajectories of the human brain and neurobehavior.

Systematic review registration

https://clinicaltrials.gov/, CRD42020158734.

Physical Activity in Pediatric Inflammatory Bowel Disease: A Scoping Review

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic, systemic condition affecting the gastrointestinal tract. IBD can be severe and are associated with impairment in growth, school absences, abdominal pain, and fatigue. Physical activity (PA) could have an anti-inflammatory effect in addition to other benefits. It is important to address the possible risks, physiological effects of PA, and potential barriers, and facilitators for PA participation in pediatric IBD. However, potential barriers and facilitators to PA have yet to be adequately described.

METHODS

We conducted a scoping review to map and describe the current literature on PA in pediatric IBD populations between 1980 and April 2022 using Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines for Scoping reviews.

RESULTS

Nineteen articles were identified including 10 descriptive, 6 interventional, and 3 physiological responses to PA studies. Patients and healthy controls demonstrated similar responses to exercise. Barriers to participation were low self-esteem, body image, and active IBD symptoms. Facilitators included personal interest, activity with friends, and support from family.

CONCLUSION

This review highlighted that PA participation may reduce in children with IBD-related symptoms. Short- and medium-term impacts of PA on immune modulation require further study; it is possible that regular PA does not negatively affect biomarkers of disease activity.

Overcoming cancer risk in inflammatory bowel disease: new insights into preventive strategies and pathogenesis mechanisms including interactions of immune cells, cancer signaling pathways, and gut microbiota

Inflammatory bowel disease (IBD), characterized primarily by gastrointestinal inflammation, predominantly manifests as Crohn's disease (CD) and ulcerative colitis (UC). It is acknowledged that Inflammation plays a significant role in cancer development and patients with IBD have an increased risk of various cancers. The progression from inflammation to carcinogenesis in IBD is a result of the interplay between immune cells, gut microbiota, and carcinogenic signaling pathways in epithelial cells. Long-term chronic inflammation can lead to the accumulation of mutations in epithelial cells and the abnormal activation of carcinogenic signaling pathways. Furthermore, Immune cells play a pivotal role in both the acute and chronic phases of IBD, contributing to the transformation from inflammation to tumorigenesis. And patients with IBD frequently exhibit dysbiosis of the intestinal microbiome. Disruption of the gut microbiota and subsequent immune dysregulation are central to the pathogenesis of both IBD and colitis associated colorectal cancer (CAC). The proactive management of inflammation combined with regular endoscopic and tumor screenings represents the most direct and effective strategy to prevent the IBD-associated cancer.

The protective effect of Schisandra chinensis (Turcz.) Baill. polysaccharide on DSS-induced ulcerative colitis in mice via the modulation of gut microbiota and inhibition of NF-κB activation

BACKGROUND

Schisandra chinensis (Turcz.) Baill, a fruit utilized in traditional Chinese medicine (TCM), has a long history of medical application. It has been used to treat diseases of the gastrointestinal tract. Schisandra chinensis (Turcz.) Baill polysaccharide (SACP) is an important biologically active ingredient that has been shown to have a variety of beneficial effects including immune regulation and anti-oxidative properties. Ulcerative colitis (UC) is a complicated gastrointestinal inflammatory disease. We explore the protective effect of SACP against UC.

RESULTS

Schisandra chinensis (Turcz.) Baill polysaccharide significantly reduced the disease activity index (DAI) and levels of myeloperoxidase(MPO) and malondialdehyde (MDA) in colonic tissue. It also alleviated weight loss and histopathological damage of mice. The expression of MUC2 and occludin proteins was increased and the barrier function of the colonic mucosa was enhanced by SACP treatment. NF-κB pathway activation was also inhibited and the production of pro-inflammatory cytokines was decreased whereas anti-inflammatory cytokines were increased. 16SrDNA sequencing of fecal flora showed that SACP increased the abundance of Muribaculaceaeunclassified, LachnospiraceaeNK4A136group and reduced the abundance of Bacteroides and Erysipelatoclostridium.

CONCLUSION

Schisandra chinensis (Turcz.) Baill polysaccharide can protect against Dextran Sulfate Sodium Salt (DSS)-induced ulcerative colitis in mice. © 2023 Society of Chemical Industry.

The role of intestinal microecology in inflammatory bowel disease and colorectal cancer: A review

Intestinal microecology is a dominant and complex microecological system in human body. Generally, intestinal microecosystem consists of normal symbiotic flora and its living environment (including intestinal epithelial tissue and intestinal mucosal immune system). Commensal flora is the core component of microecology. Both structures of intestinal mucosa and functions of immune system are essential to maintain homeostasis of intestinal microecosystem. Under normal conditions, intestinal microorganisms and intestinal mucosa coordinate with each other to promote host immunity. When certain factors in the intestine are altered, such as disruption of the intestinal barrier causing dysbiosis of the intestinal flora, the immune system of the host intestinal mucosa makes a series of responses, which leads to the development of intestinal inflammation and promotes colorectal cancer. In this review, to further understand the relationship between intestinal microecology and intestinal diseases, we systematically elaborate the composition of the intestinal mucosal immune system, analyze the relationship between intestinal flora and mucosal immune system, and the role of intestinal flora on intestinal inflammatory diseases and colorectal cancer.

Intestinal Microbiota and Metabolomics Reveal the Role of Auricularia delicate in Regulating Colitis-Associated Colorectal Cancer

BACKGROUND

The edible fungus Auricularia delicate (ADe) is commonly employed in traditional medicine for intestinal disorders; however, its inhibitory effect on colitis-associated colorectal cancer (CAC) and the underlying mechanisms remain unexplored. (2) Methods: The inhibitory effect of ADe on CAC was investigated using a mouse model induced by azoxymethane/dextran sulfate sodium.

RESULTS

ADe effectively suppressed the growth and number of intestinal tumors in mice. Intestinal microbiota analyses revealed that ADe treatment increased Akkermansia and Parabacteroides while it decreased Clostridium, Turicibacter, Oscillospira, and Desulfovibrio. ADe regulated the levels of 2'-deoxyridine, creatinine, 1-palmitoyl lysophosphatidylcholine, and choline in serum. Furthermore, the levels of these metabolites were associated with the abundance of Oscillospira and Paraacteroides. ADe up-regulated the free fatty acid receptor 2 and β-Arrestin 2, inhibited the nuclear factor kappa B (NF-κB) pathway, and significantly attenuated the levels of inflammatory cytokines, thereby mitigating the inflammatory in CAC mice.

CONCLUSIONS

The protective effect of ADe in CAC mice is associated with the regulation of intestinal microbiota, which leads to the inhibition of NF-kB pathway and regulation of inflammation.

The Impact of Intestinal Inflammation on Nematode's Excretory-Secretory Proteome

Parasitic nematodes and their products are promising candidates for therapeutics against inflammatory bowel diseases (IBD). Two species of nematodes, the hookworm Necator americanus and the whipworm Trichuis suis, are being used in clinical treatment trials of IBD referred to as "helminth therapy". Heligmosomoides polygyrus is a well-known model for human hookworm infections. Excretory-secretory (ES) products of H. polygyrus L4 stage that developed during colitis show a different immunomodulatory effect compared to the ES of H. polgyrus from healthy mice. The aim of the study was to evaluate excretory-secretory proteins produced by H. polygyrus L4 stage males and females that developed in the colitic milieu. Mass spectrometry was used to identify proteins. Blast2GO was used to investigate the functions of the discovered proteins. A total of 387 proteins were identified in the ES of H. polygyrus L4 males (HpC males), and 330 proteins were identified in the ES of L4 females that developed in the colitic milieu (HpC females). In contrast, only 200 proteins were identified in the ES of L4 males (Hp males) and 218 in the ES of L4 females (Hp females) that developed in control conditions. Most of the proteins (123) were detected in all groups. Unique proteins identified in the ES of HpC females included annexin, lysozyme-2, apyrase, and galectin. Venom allergen/Ancylostoma-secreted protein-like, transthyretin-like family proteins, and galectins were found in the secretome of HpC males but not in the secretome of control males. These molecules may be responsible for the therapeutic effects of nematodes in DSS-induced colitis.

The Underrated Gut Microbiota Helminths, Bacteriophages, Fungi, and Archaea

The microbiota inhabits the gastrointestinal tract, providing essential capacities to the host. The microbiota is a crucial factor in intestinal health and regulates intestinal physiology. However, microbiota disturbances, named dysbiosis, can disrupt intestinal homeostasis, leading to the development of diseases. Classically, the microbiota has been referred to as bacteria, though other organisms form this complex group, including viruses, archaea, and eukaryotes such as fungi and protozoa. This review aims to clarify the role of helminths, bacteriophages, fungi, and archaea in intestinal homeostasis and diseases, their interaction with bacteria, and their use as therapeutic targets in intestinal maladies.

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.

Sacral neuromodulation for refractory ulcerative colitis: safety and efficacy in a prospective observational series of eight patients

PURPOSE

Ulcerative colitis (UC) treatment is mainly based on immunosuppressive therapy. As anti-inflammatory effects of sacral neuromodulation (SNM) have been previously reported in animal models, we conducted a pilot study aimed at assessing clinical, biological, and endoscopic response but also safety of SNM use in UC refractory to medical therapy.

METHODS

Adult patients with histologically proven UC resistant to immunosuppressive therapy were invited to enroll in the study. Primary outcome was the rate of UC remission (UCDAI score ≤ 2, without any criteria > 1) at 8 weeks (W8). Secondary outcomes were biological and endoscopic response also evaluated at W8 and W16. Subsequently, every patient was followed every 6 months. Adverse events were prospectively collected for safety assessment during the follow-up.

RESULTS

Eight patients, with mean age 47 years old, suffering from UC for 2-13 years were included. There were no complications in relation to SNM procedure. The acceptance of the device was excellent in all patients. Clinical and endoscopic remission was obtained at W8 in one patient (12.5%) and three other patients (37.5%) were responders at W16. At review (mean follow-up of 4 years), two patients (25%) were in remission and two (25%) were responders.

CONCLUSION

SNM application is safe in patients suffering from refractory UC. Effects on disease activity were mainly observed after 16 weeks. Larger prospective studies are mandatory, but SNM could be a way to reinforce medical therapy and reduce the use of immunosuppressive drugs.

Safety and Efficacy of Fecal Microbiota Transplantation in Treatment of Inflammatory Bowel Disease in the Pediatric Population: A Systematic Review and Meta-Analysis

Background and Aims: Fecal microbiota transplantation (FMT) has been increasingly studied in the inflammatory bowel disease (IBD) population. However, most studies have focused on the adult population, and the safety and efficacy of FMT in a pediatric population is less well understood. This systematic review and meta-analysis investigates the safety and efficacy of FMT in a pediatric IBD population. Methods: A comprehensive literature search of publications published prior to 30 June 2022 was undertaken. Safety data, IBD-related outcomes, and microbiome analysis were obtained from these studies when accessible. Individual estimates of each study were pooled, and sensitivity analysis was conducted. Results: Eleven studies satisfied our eligibility criteria. The calculated pooled rate of adverse events was 29% (95% confidence interval [CI]: 15.0%, 44.0%; p < 0.001; I2 = 89.0%, Q = 94.53), and the calculated pooled rate of serious adverse events was 10% (95% confidence interval [CI]: 6.0%, 14.0%; p = 0.28; I2 = 18.0%, Q = 9.79). One month after FMT, clinical response was achieved in 20/34 (58.8%) pediatric IBD patients, clinical remission was achieved in 22/34 (64.7%), and both clinical response and remission were achieved in 15/34 (44.1%) pediatric IBD patients. Conclusions: FMT can be a safe and effective treatment in the pediatric IBD population and may demonstrate improved safety and efficacy in the pediatric population compared to the adult population. However, our results are limited by a lack of established protocol as well as long-term follow-up for FMT in a pediatric IBD population.

Response Variability to Drug Testing in Two Models of Chemically Induced Colitis

The lack of knowledge regarding the pathogenesis of IBD is a challenge for the development of more effective and safer therapies. Although in vivo preclinical approaches are critical for drug testing, none of the existing models accurately reproduce human IBD. Factors that influence the intra-individual response to drugs have barely been described. With this in mind, our aim was to compare the anti-inflammatory efficacy of a new molecule (MTADV) to that of corticosteroids in TNBS and DSS-induced colitis mice of both sexes in order to clarify further the response mechanism involved and the variability between sexes. The drugs were administered preventively and therapeutically, and real-time bioluminescence was performed for the in vivo time-course colitis monitoring. Morphometric data were also collected, and colonic cytokines and acute plasma phase proteins were analyzed by qRT-PCR and ELISA, respectively-bioluminescence images correlated with inflammatory markers. In the TNBS model, dexamethasone worked better in females, while MTADV improved inflammation in males. In DSS-colitis, both therapies worked similarly. Based on the molecular profiles, interaction networks were constructed to pinpoint the drivers of therapeutic response that were highly dependent on the sex. In conclusion, our results suggest the importance of considering sex in IBD preclinical drug screening.

Wogonin regulates colonocyte metabolism via PPARγ to inhibit Enterobacteriaceae against dextran sulfate sodium-induced colitis in mice

To investigate the potential effects and mechanism of wogonin on dextran sulfate sodium (DSS)-induced colitis, 70 male mice were administered wogonin (12.5, 25, 50 mg·kg^-1 ·d^-1 , i.g.) for 10 days, meanwhile, in order to induce colitis, the mice were free to drink 3% DSS for 6 days. We found that wogonin could obviously ameliorate DSS-induced colitis, including preventing colon shortening and inhibiting pathological damage. In addition, wogonin could increase the expression of PPARγ, which not only restores intestinal epithelial hypoxia but also inhibits iNOS protein to reduce intestinal nitrite levels. All these effects facilitated a reduction in the abundance of Enterobacteriaceae in DSS-induced colitis mice. Therefore, compared with the DSS group, the number of Enterobacteriaceae in the intestinal flora was significantly reduced after administration of wogonin or rosiglitazone by 16s rDNA technology. We also verified that wogonin could promote the expression of PPARγ mRNA and protein in Caco-2 cells, and this effect disappeared when PPARγ signal was inhibited. In conclusion, our study suggested that wogonin can activate the PPARγ signal of the Intestinal epithelium to ameliorate the Intestinal inflammation caused by Enterobacteriaceae bacteria expansion.

Risk of Cancer in Patients with Inflammatory Bowel Diseases and Keys for Patient Management

Chronic inflammation in patients with Inflammatory Bowel Disease (IBD) leads to an increased risk of colorectal cancer, small bowel cancer, intestinal lymphoma and cholangiocarcinoma. However, treatments for IBD have also been associated with an increased risk of neoplasms. Patients receiving Thiopurines (TPs) have an increased risk of hematologic malignancies, non-melanoma skin cancer, urinary tract neoplasms and cervical cancer. Anti-TNFs have been associated with a higher risk of neoplasms, mainly lymphomas and melanomas; however, the data are controversial, and some recent studies do not confirm the association. Nevertheless, other biologic agents, such as ustekinumab and vedolizumab, have not shown an increased risk of any neoplasm to date. The risk of malignancies with tofacitinib exists, but its magnitude and relationship with previous treatment with TPs is not defined, so more studies from daily clinical practice are needed. Although biologic therapy seems to be safe for patients with current cancer or a prior history of cancer, as has been demonstrated in other chronic inflammatory conditions, prospective studies in this specific population are needed. Until that time, it is crucial to manage such conditions via the combined clinical expertise of the gastroenterologist and oncologist.

Probiotics Mechanism of Action on Immune Cells and Beneficial Effects on Human Health

Immune cells and commensal microbes in the human intestine constantly communicate with and react to each other in a stable environment in order to maintain healthy immune activities. Immune system-microbiota cross-talk relies on a complex network of pathways that sustain the balance between immune tolerance and immunogenicity. Probiotic bacteria can interact and stimulate intestinal immune cells and commensal microflora to modulate specific immune functions and immune homeostasis. Growing evidence shows that probiotic bacteria present important health-promoting and immunomodulatory properties. Thus, the use of probiotics might represent a promising approach for improving immune system activities. So far, few studies have been reported on the beneficial immune modulatory effect of probiotics. However, many others, which are mainly focused on their metabolic/nutritional properties, have been published. Therefore, the mechanisms behind the interaction between host immune cells and probiotics have only been partially described. The present review aims to collect and summarize the most recent scientific results and the resulting implications of how probiotic bacteria and immune cells interact to improve immune functions. Hence, a description of the currently known immunomodulatory mechanisms of probiotic bacteria in improving the host immune system is provided.

Cross talk between the gut microbiome and host immune response in ulcerative colitis: nonpharmacological strategies to improve homeostasis

Ulcerative colitis (UC) is a chronic disease that is characterized by diffuse inflammation of the colonic and rectal mucosa. The burden of UC is rising globally with significant disparities in levels and trends of disease in different countries. The pathogenesis of UC involves the presence of pathogenic factors including genetic, environmental, autoimmune, and immune-mediated components. Evidence suggests that disturbed interactions between the host immune system and gut microbiome contribute to the origin and development of UC. Current medications for UC include antibiotics, corticosteroids, and biological drugs, which can have deleterious off-target effects on the gut microbiome, contributing to increased susceptibility to severe infections and chronic immunosuppression. Alternative, nonpharmacological, and behavioral interventions have been proposed as safe and effective treatments to alleviate UC, while also holding the potential to improve overall life quality. This mini-review will discuss the interactions between the immune system and the gut microbiome in the case of UC. In addition, we suggest nonpharmacological and behavioral strategies aimed at restoring a proper microbial-immune relationship.

Global research trends on inflammatory bowel diseases and colorectal cancer: A bibliometric and visualized study from 2012 to 2021

Inflammatory bowel disease (IBD) is a chronic non-specific inflammatory disease of intestinal tract and a common digestive system disease. Current studies have shown that IBD significantly increases the incidence of colorectal cancer (CRC), and is positively correlated with the degree and extent of inflammation of IBD. The relationship between IBD and CRC has attracted extensive attention. However, the relationship between IBD and CRC has not been systematically studied by bibliometrics and visual analysis. This study conducted bibliometric analysis based on 3528 publications from the Core Collection of Web of Science to determine the research status, research hotspots and frontiers of this field. The results show that the number of publications has increased significantly over the past 10 years. The cooperative network analysis shows that the United States, Mayo Clin and Bo Shen are the country, institution and author with the most publications respectively. Belgium, Icahn Sch Med Mt Sinai and Erik Mooiweer are the most collaborative country, institution and author respectively. Analysis of keywords and references showed that inflammation, intestinal flora, and obesity were hot topics in this field. Analysis of keyword outbreaks shows that the gut microbiome and metabolism will be an emerging new research area and a potential hot spot for future research. This study is the first to visually examine the association between IBD and CRC using bibliometrics and visual analysis, and to predict potential future research trends.

Effects of Long Non-Coding RNAs Induced by the Gut Microbiome on Regulating the Development of Colorectal Cancer

Although an imbalanced gut microbiome is closely associated with colorectal cancer (CRC), how the gut microbiome affects CRC is not known. Long non-coding RNAs (lncRNAs) can affect important cellular functions such as cell division, proliferation, and apoptosis. The abnormal expression of lncRNAs can promote CRC cell growth, proliferation, and metastasis, mediating the effects of the gut microbiome on CRC. Generally, the gut microbiome regulates the lncRNAs expression, which subsequently impacts the host transcriptome to change the expression of downstream target molecules, ultimately resulting in the development and progression of CRC. We focused on the important role of the microbiome in CRC and their effects on CRC-related lncRNAs. We also reviewed the impact of the two main pathogenic bacteria, Fusobacterium nucleatum and enterotoxigenic Bacteroides fragilis, and metabolites of the gut microbiome, butyrate, and lipopolysaccharide, on lncRNAs. Finally, available therapies that target the gut microbiome and lncRNAs to prevent and treat CRC were proposed.

Comprehensive analysis of microbiome, metabolome and transcriptome revealed the mechanisms of Moringa oleifera polysaccharide on preventing ulcerative colitis

This study aimed to investigate the protective effect of Moringa oleifera polysaccharide (MOP) on ulcerative colitis (UC) and explore its mechanism through the combined analysis of microbiome, metabolome and transcriptome. A UC model in mice was established using dextran sulphate sodium. After a 21-day experiment, results showed that MOP could inhibit the weight loss and disease activity index in UC mice. The intervention of MOP decreased the expression of inflammatory cytokines and promoted the secretion of tight junctions. MOP could promote the growth of probiotics such as Lachnospiraceae_NK4A136, Intestinimonas and Bifidobacterium in UC mice. The results of metabolomic and transcriptomic analysis indicated that MOP could regulated the metabolism of polyunsaturated fatty acid and PPAR, TLR and TNF signalling pathways might play important roles in the process. Altogether, MOP could be used as a functional food to prevent UC.

Gut microbiota, inflammatory bowel disease and colorectal cancer

The gut microbiota is a complex community of microorganisms that inhabit the digestive tracts of humans, living in symbiosis with the host. Dysbiosis, characterized by an imbalance between the beneficial and opportunistic gut microbiota, is associated with several gastrointestinal disorders, such as irritable bowel syndrome (IBS); inflammatory bowel disease (IBD), represented by ulcerative colitis and Crohn’s disease; and colorectal cancer (CRC). Dysbiosis can disrupt the mucosal barrier, resulting in perpetuation of inflammation and carcinogenesis. The increase in some specific groups of harmful bacteria, such as Escherichia coli (E. coli) and enterotoxigenic Bacteroides fragilis (ETBF), has been associated with chronic tissue inflammation and the release of pro-inflammatory and carcinogenic mediators, increasing the chance of developing CRC, following the inflammation-dysplasia-cancer sequence in IBD patients. Therefore, the aim of the present review was to analyze the correlation between changes in the gut microbiota and the development and maintenance of IBD, CRC, and IBD-associated CRC. Patients with IBD and CRC have shown reduced bacterial diversity and abundance compared to healthy individuals, with enrichment of Firmicute sand Bacteroidetes. Specific bacteria are also associated with the onset and progression of CRC, such as Fusobacterium nucleatum, E. coli, Enterococcus faecalis, Streptococcus gallolyticus, and ETBF. Future research can evaluate the advantages of modulating the gut microbiota as preventive measures in CRC high-risk patients, directly affecting the prognosis of the disease and the quality of life of patients.

Effect of gut microbiota in the colorectal cancer and potential target therapy

The symbiotic interaction between gut microbiota and the digestive tract is an important factor in maintaining the intestinal environment balance. Colorectal cancer (CRC) is a complex disease involving the interaction between tumour cells and a large number of microorganisms. The microbiota is involved in the occurrence, development and prognosis of colorectal cancer. Several microbiota species have been studied, such as Fusobacterium nucleatum (F. nucleatum), Enterotoxigenic Bacteroides fragilis (ETBF), Streptococcus bovis (S. bovis), Lactobacillus, and Bifidobacterium. Studies about the interaction between microbiota and CRC were retrieved from Embase, PubMed, Ovid and Web of Science up to 21 Oct 2021. This review expounded on the effect of microbiota on CRC, especially the dysregulation of bacteria and carcinogenicity. The methods of gut microbiota modifications representing novel prognostic markers and innovative therapeutic strategies were also described.

The Role of C-Type Lectin Receptor Signaling in the Intestinal Microbiota-Inflammation-Cancer Axis

As a subset of pattern recognition receptors (PRRs), C-type lectin-like receptors (CLRs) are mainly expressed by myeloid cells as both transmembrane and soluble forms. CLRs recognize not only pathogen associated molecular patterns (PAMPs), but also damage-associated molecular patterns (DAMPs) to promote innate immune responses and affect adaptive immune responses. Upon engagement by PAMPs or DAMPs, CLR signaling initiates various biological activities in vivo, such as cytokine secretion and immune cell recruitment. Recently, several CLRs have been implicated as contributory to the pathogenesis of intestinal inflammation, which represents a prominent risk factor for colorectal cancer (CRC). CLRs function as an interface among microbiota, intestinal epithelial barrier and immune system, so we firstly discussed the relationship between dysbiosis caused by microbiota alteration and inflammatory bowel disease (IBD), then focused on the role of CLRs signaling in pathogenesis of IBD (including Mincle, Dectin-3, Dectin-1, DCIR, DC-SIGN, LOX-1 and their downstream CARD9). Given that CLRs mediate intricate inflammatory signals and inflammation plays a significant role in tumorigenesis, we finally highlight the specific effects of CLRs on CRC, especially colitis-associated cancer (CAC), hoping to open new horizons on pathogenesis and therapeutics of IBD and CAC.