High-throughput clone library analysis of the mucosa-associated microbiota reveals dysbiosis and differences between inflamed and non-inflamed regions of the intestine in inflammatory bowel disease

Grifola frondosa polysaccharide's therapeutic potential in oxazolone-induced ulcerative colitis

Grifola frondosa polysaccharide (GFP) is a consumable fungus recognized for its potential health advantages. The present study aimed to investigate the development and potential etiologies of ulcerative colitis (UC) utilizing oxazolone (OXZ) as an inducer in mice, along with assessing the therapeutic effects of GFP at varying doses in UC mice, with sulfasalazine (SASP) serving as the positive control. The obtained results indicated that OXZ intervention in mice induced numerous physical manifestations of UC, including increased disease activity index (DAI), decreased goblet cell division, enhanced fibrosis, reduced expression of Claudin1 and Zona encludens protein1 (ZO-1), decreased proliferative activity of colonic mucosal epithelial cells, disturbed oxidation balance, and alterations in intestinal flora. Nonetheless, GFP intervention significantly ameliorated or even resolved these abnormal indicators to a considerable extent. Consequently, this study suggests that GFP might serve as a prebiotic to regulate intestinal flora, mitigate enterotoxin production, restore oxidative balance, thereby reducing the generation of inflammatory mediators, restoring the intestinal barrier, and ultimately improving OXZ-induced UC in mice. GFP demonstrates promising potential as a candidate drug for colitis treatment and as a dietary supplement for alleviating intestinal inflammatory issues.

Insecticide-Induced Metabolic Dysregulation in Model Microbe E. coli Discovered by Comprehensive Metabolic Profiling

Fipronil, malathion, and permethrin are widely used insecticides in agriculture, public areas, and residential spaces. The globally abused application of these chemicals results in residues surpassing established maximum residue levels, giving rise to potential toxicity in unintended organisms. Long-term exposure and the persistent accumulation of these insecticides in animals and humans pose threats such as neurotoxicity, liver and kidney damage, and microbiota dysbiosis. Despite the known risks, the specific impact of these insecticides on gut microbiota and their metabolic processes, as well as the subsequent effects on host health, remain largely unknown. This study aimed to address this gap by utilizing nonpathogenic Escherichia coli as a representative of human gut bacteria and examining its growth and metabolic perturbations induced by exposure to fipronil, malathion, and permethrin. Our research showed that exposure of E. coli to fipronil, malathion, and permethrin at physiologically relevant concentrations resulted in significant growth inhibition. Furthermore, we have observed the biodegradation of fipronil and permethrin by E. coli, while no biodegradation was found for malathion. Thus, E. coli is capable of degrading fipronil and permethrin, thereby enabling the removal of those substances. Next, we studied how insecticides affect bacterial metabolism to understand their influence on the functions of the microbes. Our metabolomics analysis revealed chemical-dependent alterations in metabolic profiles and metabolite compositions following insecticide exposure. These changes encompassed shifts in carboxylic acids and derivatives, organooxygen compounds, as well as indoles and their derivatives. To gain a deeper insight into the systematic changes induced by these insecticides, we conducted a metabolic pathway analysis. Our data indicated that fipronil, compared with malathion and permethrin, exhibited opposite regulation in glycine, serine, and threonine metabolism and valine, leucine, and isoleucine biosynthesis. In summary, our study demonstrates the capability of E. coli to degrade fipronil and permethrin, leading to their removal, while malathion remains unaffected. Additionally, we reveal chemical-dependent alterations in bacterial metabolism induced by insecticide exposure, with specific impacts on metabolic pathways, particularly in pathways related to amino acid metabolism.

The Role of Fecal Microbiota Transplantation in IBD

Gut microbiota dysbiosis has a critical role in the pathogenesis of inflammatory bowel diseases, prompting the exploration of novel therapeutic approaches like fecal microbiota transplantation, which involves the transfer of fecal microbiota from a healthy donor to a recipient with the aim of restoring a balanced microbial community and attenuating inflammation. Fecal microbiota transplantation may exert beneficial effects in inflammatory bowel disease through modulation of immune responses, restoration of mucosal barrier integrity, and alteration of microbial metabolites. It could alter disease course and prevent flares, although long-term durability and safety data are lacking. This review provides a summary of current evidence on fecal microbiota transplantation in inflammatory bowel disease management, focusing on its challenges, such as variability in donor selection criteria, standardization of transplant protocols, and long-term outcomes post-transplantation.

Enhanced anti-inflammatory activity of chlorogenic acid via folic acid-TPGS-modified liposomes encapsulation: characterization and In vivo evaluation on colitis mice

Introduction

Chlorogenic acid (CGA) has been identified to possess salient anti-inflammatory, antioxidant, and anticancer attributes. However, its application is limited by its instability and low bioavailability. Liposomes have been considered effective pharmaceutical delivery vehicles due to their ability to continuously release loaded drugs, improve drug stability, and display good biocompatibility. They can be easily modified by other small molecules to acquire additional biological functions. In this study, we developed and characterized folic acid-TPGS-modified chlorogenic acid liposome (FTCLP) and evaluated its anti-inflammatory activity.

Methods

The successful encapsulation of CGA within FTCLP was confirmed through examination using electron microscopy, fourier-transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). The in vitro release characteristics of FTCLP were evaluated using the dialysis bag membrane method. Meanwhile, a dextran sulfate sodium (DSS) -induced colitis model was employed to investigate the anti-inflammatory effect of FTCLP and its mechanism.

Results

The FTCLP exhibited an encapsulation efficiency (EE) of 84.85 ± 1.20% and a drug loading (DL) of 11.67 ± 0.04%. The particle size of FTCLP was determined to be 150.63 ± 0.71 nm, with a polydispersity index (PDI) of 0.198 ± 0.02 and a zeta potential of 2.61 ± 0.38 mV. The in vitro release profile followed the Higuchi model, indicating sustained-release characteristics. The in vivo study demonstrated that FTCLP treatment was effective in improving the symptoms of DSS-induced inflammatory response, as evidenced by mitigation of weight loss, reduction in the disease activity index (DAI) score, restoration of colon length, and attenuation of colon tissue damage. Furthermore, the levels of pro-inflammatory cytokines, including interferon-gamma (INF-γ), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6), were markedly diminished in both the serum and colon tissue. FTCLP was also observed to suppress the expression of INF-γ, IL-1β, IL-6, tumor necrosis factor-alpha (TNF-α), and nuclear factor kappa B (NF-κB) p65, while concomitantly upregulating the expression of Janus kinase (JAK) and signal transducer and activator of transcription 3 (STAT3). Besides, the administration of FTCLP was found to result in an increase in the abundance of Lactobacillaceae and Peptostreptococcaceae, while decreasing the abundance of Bacteroidaceae, Rikenellaceae, and Helicobacteraceae.

Conclusion

Following encapsulation of CGA within liposomes, FTCLP revealed favorable stability and sustained release properties, and enhanced the anti-inflammatory effects by modulating multiple inflammation-related biomarkers. FTCLP has the potential to be a safe and effective drug for targeted therapy of colitis.

Allium tuberosum-derived nanovesicles with anti-inflammatory properties prevent DSS-induced colitis and modify the gut microbiome

Edible plant-derived nanovesicles (ePDNs) have shown potential as a non-pharmacological option for inflammatory bowel disease (IBD) by maintaining gut health and showing anti-inflammatory effects. However, the effects of Allium tuberosum-derived nanovesicles (ADNs) on colitis have not been studied to date. Here, we extracted exosome-like nanovesicles from Allium tuberosum and investigated whether they have an anti-inflammatory effect in RAW 264.7 cells and colitis mice. The results showed that ADNs reduced the elevated levels of inflammatory factors such as IL-1β, IL-6, TNF-α, and NF-κB pathway-related proteins as a consequence of lipopolysaccharide (LPS) stimulation in RAW 264.7 cells. Furthermore, our mouse experiments demonstrated that ADNs could ameliorate dextran sulfate sodium (DSS)-induced colitis symptoms (e.g., increased disease activity index score, intestinal permeability, and histological appearance). Additionally, ADNs counteracted DSS-induced colitis by downregulating the expression of serum amyloid A (SAA), IL-1β, IL-6, and TNF-α and increasing the expression of tight junction proteins (ZO-1 and occludin) and the anti-inflammatory cytokine IL-10. 16S rRNA gene sequencing showed that ADN intervention restored the gut microbial composition, which was similar to that of the DSS non-treated group, by decreasing the ratio of Firmicutes to Bacteroidetes and the relative abundance of Proteobacteria. Furthermore, ADNs induced acetic acid production along with an increase in the abundance of Lactobacillus. Overall, our findings suggest that ADN supplementation has a crucial role in maintaining gut health and is a novel preventive therapy for IBD.

Inflammatory Bowel Disease and Cardiovascular Disease: An Integrative Review With a Focus on the Gut Microbiome

Inflammatory bowel disease (IBD), which includes Crohn's disease and ulcerative colitis, is a chronic inflammatory condition of the gastrointestinal tract. Recent research indicates a significant link between IBD and cardiovascular disease (CVD), the leading cause of global morbidity and mortality. This review examines the association between IBD and CVD, emphasizing the role of the gut microbiome in this relationship. IBD patients have a higher risk of cardiovascular events, such as coronary artery disease, heart failure, and cerebrovascular incidents, primarily due to chronic systemic inflammation, genetic factors, and gut microbiota imbalance (dysbiosis). Dysbiosis in IBD increases intestinal permeability, allowing bacterial products to enter the bloodstream, which promotes inflammation and endothelial dysfunction, contributing to CVD. Understanding the gut microbiome's role in IBD and CVD suggests new therapeutic interventions. Modulating the microbiome through diet, probiotics, and fecal microbiota transplantation (FMT) are promising research avenues. These interventions aim to restore a healthy gut microbiota balance, potentially reducing inflammation and improving cardiovascular outcomes. Additionally, the review emphasizes the importance of regular cardiovascular risk assessments and personalized preventive measures in managing IBD patients. Such measures include routine monitoring of cardiovascular health, tailored lifestyle modifications, and early intervention strategies to mitigate cardiovascular risk. By integrating current knowledge, this review aims to improve understanding and management of the interconnected pathophysiology of IBD and CVD. This approach will ultimately enhance patient outcomes and provide a foundation for future research and clinical practice guidelines in this area.

Explore the underlying oral efficacy of α-, β-, γ-Cyclodextrin against the ulcerative colitis using in vitro and in vivo studies assisted by network pharmacology

The incidence of ulcerative colitis (UC) is rising worldwide. As a refractory and recurrent disease, UC could seriously affect the patients' quality of life. However, current clinical medical treatments for UC are accompanied by various side effects, especially for long-term applications. Here, the underlying efficacy of cyclodextrins (CDs) was studied. As common excipients, CDs endow proven safety for long-term applications. Results of predictive methods derived from network pharmacology prompted the potential anti-inflammatory effects of CDs by oral administration. RAW264.7 cell experiments verified that CDs could inhibit the excessive secretion of TNF-α (β-CD > α-CD ≈ γ-CD), IL-6, and NO (α-CD > β-CD ≈ γ-CD) as predicted. In mice with DSS-induced acute UC, oral administration of CDs could effectively mitigate the pathological damage of colon tissue and reduce the level of inflammatory mediators. Moreover, 16S rRNA sequencing displayed that gut microbes disturbed by DSS were significantly regulated by CDs. Conclusively, the study showed the therapeutic application prospects of CDs in UC treatment and indicated the feasibility and advantages of developing 'new' therapeutic activities of 'old' ingredients.Communicated by Ramaswamy H. Sarma.

An energy landscape approach reveals the potential key bacteria contributing to the development of inflammatory bowel disease

The dysbiosis of microbiota has been reported to be associated with numerous human pathophysiological processes, including inflammatory bowel disease (IBD). With advancements in high-throughput sequencing, various methods have been developed to study the alteration of microbiota in the development and progression of diseases. However, a suitable approach to assess the global stability of the microbiota in disease states through time-series microbiome data is yet to be established. In this study, we have introduced a novel Energy Landscape construction method, which incorporates the Latent Dirichlet Allocation (LDA) model and the pairwise Maximum Entropy (MaxEnt) model for their complementary advantages, and demonstrate its utility by applying it to an IBD time-series dataset. Through this approach, we obtained the microbial assemblages' energy profile of the whole microbiota under the IBD condition and uncovered the hidden stable stages of microbiota structure during the disease development with time-series microbiome data. The Bacteroides-dominated assemblages presenting in multiple stable states suggest the potential contribution of Bacteroides and interactions with other microbial genera, like Alistipes, and Faecalibacterium, to the development of IBD. Our proposed method provides a novel and insightful tool for understanding the alteration and stability of the microbiota under disease states and offers a more holistic view of the complex dynamics at play in microbiota-mediated diseases.

Microbiota and IBD: Current knowledge and future perspectives

Inflammatory Bowel Disease (IBD) is a chronic relapsing-remitting disease with a remarkable increase in incidence worldwide and a substantial disease burden. Although the pathophysiology is not fully elucidated yet an aberrant immune reaction against the intestinal microbiota and the gut microbial dysbiosis have been identified to play a major role. The composition of gut microbiota in IBD patients is distinct from that of healthy individuals, with certain organisms predominating over others. Differences in the microbial dysbiosis have been also observed between Crohn Disease (CD) and Ulcerative Colitis (UC). A disruption of the microbiota's balance can lead to inflammation and intestinal damage. Microbiota composition in IBD can be affected both by endogenous (i.e., interaction with the immune system and intestinal epithelial cells) and exogenous (i.e., medications, surgery, diet) factors. The complex interplay between the gut microbiota and IBD is an area of great interest for understanding disease pathogenesis and developing new treatments. The purpose of this review is to summarize the latest evidence on the role of microbiota in IBD pathogenesis and to explore possible future areas of research.

Microbiome and its relevance to indigenous inflammatory bowel diseases in China

BACKGROUND

Inflammatory Bowel Disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract with an unknown etiology. Although dysbiosis is implicated in its pathogenesis, deep sequencing and oral microbiota study in Chinese IBD patients is absent.

AIM

To explore the role of oral / intestinal microbiota in patients with IBD and the potential associations therein.

METHODS

Clinical data, fecal and saliva samples were harvested from 80 patients with IBD (Crohn's disease, CD, n = 69; Ulcerative colitis, UC, n = 11) and 24 normal controls. Microbiomics (16S rRNA sequencing and 16S rRNA full-length sequencing) were used to detect and analyze the difference between IBD patients and normal control.

RESULTS

Compared with normal controls, a higher abundance of the intestinal Shigella spp. (Shigella flexneri and Shigella sonnei, which were positively relate to the severity of IBD), lower abundance of intestinal probiotics (Prevotella, Faecalibacterium and Roseburia), and higher abundance of oral Neisseria were present in IBD patients with microbiome. The higher inflammation-related markers, impaired hepatic and renal function, and dyslipidaemia were present in patients with IBD. A higher intake of red meat and increased abundance of Clostridium in the gut were found in CD patients, while the elevated abundance of Ruminococcus in the gut was showed in UC ones. The bacterial composition of saliva and fecal samples was completely different, yet there was some correlation in the distribution of dominant probiotics.

CONCLUSION

Enteric dysbacteriosis and the infections of pathogenic bacteria (Shigella) may associate with the occurrence or development of IBD.

Dysbiosis in inflammatory bowel diseases: egg, not chicken

There is agreement that inflammatory bowel diseases are, both in terms of species composition and function, associated with an altered intestinal microbiome. This is usually described by the term "dysbiosis," but this is a vague definition lacking quantitative precision. In this brief narrative review, the evidence concerning the primary or secondary role of this dysbiotic state is critically evaluated. Among others, the following facts argue against a primary etiological impact: 1) There is no specific dysbiotic microbiome in IBD, 2) the presence or absence of mucosal inflammation has a profound impact on the composition of the microbiome, 3) dysbiosis is not specific for IBD but linked to many unrelated diseases, 4) antibiotics, probiotics, and microbiome transfer have a very limited therapeutic effect, 5) the microbiome in concordant twins is similar to disease-discordant twins, and 6) the microbiome in relatives of IBD patients later developing IBD is altered, but these individuals already display subclinical inflammation.

The development of probiotics and prebiotics therapy to ulcerative colitis: a therapy that has gained considerable momentum

Ulcerative colitis (UC) is increasingly common, and it is gradually become a kind of global epidemic. UC is a type of inflammatory bowel disease (IBD), and it is a lifetime recurrent disease. UC as a common disease has become a financial burden for many people and has the potential to develop into cancer if not prevented or treated. There are multiple factors such as genetic factors, host immune system disorders, and environmental factors to cause UC. A growing body of research have suggested that intestinal microbiota as an environmental factor play an important role in the occurrence and development of UC. Meanwhile, evidence to date suggests that manipulating the gut microbiome may represent effective treatment for the prevention or management of UC. In addition, the main clinical drugs to treat UC are amino salicylate and corticosteroid. These clinical drugs always have some side effects and low success rate when treating patients with UC. Therefore, there is an urgent need for safe and efficient methods to treat UC. Based on this, probiotics and prebiotics may be a valuable treatment for UC. In order to promote the wide clinical application of probiotics and prebiotics in the treatment of UC. This review aims to summarize the recent literature as an aid to better understanding how the probiotics and prebiotics contributes to UC while evaluating and prospecting the therapeutic effect of the probiotics and prebiotics in the treatment of UC based on previous publications.

Nicotine improves DSS-induced colitis by inhibiting NLRP3 and altering gut microbiota

Ulcerative colitis (UC) is a chronic recurrent inflammatory disease affecting the rectum and colon. Numerous epidemiological studies have identified smoking as a protective factor for UC. Dysbiosis of intestinal microbiota and release of inflammatory factors are well-established characteristics associated with UC. Therefore, we have observed that nicotine exhibits the potential to ameliorate colitis symptoms in UC mice. Additionally, it exerts a regulatory effect on colonic microbiota dysbiosis by promoting the growth of beneficial bacteria while suppressing harmful bacteria. Combined in vivo and in vitro investigations demonstrate that nicotine primarily impedes the assembly of NLRP3, subsequently inhibiting downstream IL-1β secretion.

Current Knowledge on the Preparation and Benefits of Cruciferous Vegetables as Relates to In Vitro, In Vivo, and Clinical Models of Inflammatory Bowel Disease

Inflammatory bowel disease is a chronic condition with a significant economic and social burden. The disease is complex and challenging to treat because it involves several pathologies, such as inflammation, oxidative stress, dysbiosis, and intestinal damage. The search for an effective treatment has identified cruciferous vegetables and their phytochemicals as potential management options for inflammatory bowel disease because they contain prebiotics, probiotics, and anti-inflammatory and antioxidant metabolites essential for a healthy gut. This critical narrative style review provides a robust insight into the pharmacological effects and benefits of crucifers and their documented bioactive compounds in in vitro and in vivo models, as well as clinical inflammatory bowel disease. The review highlights the significant impact of crucifer preparation and the presence of glucosinolates, isothiocyanates, flavonoids, and polyphenolic compounds, which are essential for the anti-inflammatory and antioxidative benefits of cruciferous vegetables, as well as their ability to promote the healthy microbial community and maintain the intestinal barrier. This review may serve as a viable nutritional guide for future research on methods and features essential to developing experiments, preventions, and treatments for inflammatory bowel disease. There is limited clinical information and future research may utilize current innovative tools, such as metabolomics, for adequate knowledge and effective translation into clinical therapy.

Pharmacological effects of ginseng and ginsenosides on intestinal inflammation and the immune system

Intestinal inflammatory imbalance and immune dysfunction may lead to a spectrum of intestinal diseases, such as inflammatory bowel disease (IBD) and gastrointestinal tumors. As the king of herbs, ginseng has exerted a wide range of pharmacological effects in various diseases. Especially, it has been shown that ginseng and ginsenosides have strong immunomodulatory and anti-inflammatory abilities in intestinal system. In this review, we summarized how ginseng and various extracts influence intestinal inflammation and immune function, including regulating the immune balance, modulating the expression of inflammatory mediators and cytokines, promoting intestinal mucosal wound healing, preventing colitis-associated colorectal cancer, recovering gut microbiota and metabolism imbalance, alleviating antibiotic-induced diarrhea, and relieving the symptoms of irritable bowel syndrome. In addition, the specific experimental methods and key control mechanisms are also briefly described.

Assessment of the Inflammatory Effects of Gut Microbiota from Human Twins Discordant for Ulcerative Colitis on Germ-free Mice

Disturbances in gut microbiota are prevalent in inflammatory bowel disease (IBD), which includes ulcerative colitis (UC). However, whether these disturbances contribute to development of the disease or are a result of the disease is unclear. In pairs of human twins discordant for IBD, the healthy twin has a higher risk of developing IBD and a gut microbiota that is more similar to that of IBD patients as compared with healthy individuals. Furthermore, appropriate medical treatment may mitigate these disturbances. To study the correlation between microbiota and IBD, we transferred stool samples from a discordant human twin pair: one twin being healthy and the other receiving treatment for UC. The stool samples were transferred from the disease-discordant twins to germ-free pregnant dams. Colitis was induced in the offspring using dextran sodium sulfate. As compared with offspring born to mice dams inoculated with stool from the healthy cotwin, offspring born to dams inoculated with stool from the UC-afflicted twin had a lower disease activity index, less gut inflammation, and a microbiota characterized by higher α diversity and a more antiinflammatory profile that included the presence and higher abundance of antiinflammatory species such as Akkermansia spp., Bacteroides spp., and Parabacteroides spp. These findings suggest that the microbiota from the healthy twin may have had greater inflammatory properties than did that of the twin undergoing UC treatment.

A Report of Ulcerative Colitis With Relapse on the Rectal Side of the Loop Sigmoid Colostomy and Not on the Oral Side

A patient who received a loop sigmoid colostomy was diagnosed with ulcerative colitis (pancolitis type) and treated with infliximab. Thereafter, he relapsed with intestinal inflammation only on the rectal side of the loop sigmoid colostomy and not on the oral side. Autologous fecal microbiota transplantation from the proximal intestine to the distal intestine was performed to treat the inflammation but was ineffective. He was treated with oral prednisolone and induced into remission. After analyzing fecal samples from the patient, we observed an alteration of the composition of the intestinal microbiota with intestinal inflammation, including a reduction of phylum Firmicutes in the inflamed distal intestine, whereas Firmicutes was conserved in the proximal non-inflamed intestine and recovered in the distal intestine after induction of remission. Thus, our results indicated that the inflammation was associated with an alteration of the intestinal microbiota.

Composition of the colon microbiota in the individuals with inflammatory bowel disease and colon cancer

The human intestine is a habitat for microorganisms and, recently, the composition of the intestinal microbiota has been correlated with the etiology of diseases such as inflammations, sores, and tumors. Although many studies have been conducted to understand the composition of that microbiota, expanding these studies to more samples and different backgrounds will improve our knowledge. In this work, we showed the colon microbiota composition and diversity of healthy subjects, patients with inflammatory bowel disease (IBD), and colon cancer by metagenomic sequencing. Our results indicated that the relative abundance of prokaryotic and eukaryotic microbes differs between the healthy vs. tumor biopsies, tumor vs. IBD biopsies, and fresh vs. paraffin-embedded tumor biopsies. Fusobacterium, Escherichia-Shigella, and Streptococcus genera were relatively abundant in fresh tumor biopsies, while Pseudomonas was significantly elevated in IBD biopsies. Additionally, another opportunist pathogen Malasseziales was revealed as the most abundant fungal clade in IBD biopsies, especially in ulcerative colitis. We also found that, while the Basidiomycota:Ascomycota ratio was slightly lower in tumor biopsies compared to biopsies from healthy subjects, there was a significant increase in IBD biopsies. Our work will contribute to the known diversity of prokaryotic and eukaryotic microbes in the colon biopsies in patients with IBD and colon cancer.

Adenosine in Intestinal Epithelial Barrier Function

At the intestinal front, several lines of defense are in place to resist infection and injury, the mucus layer, gut microbiome and strong epithelial junctions, to name a few. Their collaboration creates a resilient barrier. In intestinal disorders, such as inflammatory bowel disease (IBD), barrier function is compromised, which results in rampant inflammation and tissue injury. In response to the destruction, the intestinal epithelium releases adenosine, a small but powerful nucleoside that functions as an alarm signal. Amidst the chaos of inflammation, adenosine aims to restore order. Within the scope of its effects is the ability to regulate intestinal epithelial barrier integrity. This review aims to define the contributions of adenosine to mucus production, microbiome-dependent barrier protection, tight junction dynamics, chloride secretion and acid-base balance to reinforce its importance in the intestinal epithelial barrier.

Natural history and impact of irritable bowel syndrome-type symptoms in inflammatory bowel disease during 12 months of longitudinal follow-up

BACKGROUND

Little is known about the natural history and impact of irritable bowel syndrome (IBS)-type symptoms on psychological health and quality of life in inflammatory bowel disease (IBD). We aimed to address this in a 12-month longitudinal follow-up study of secondary care patients.

METHODS

We collected demographic, Rome III IBS-type symptom, psychological, and quality of life data, with questionnaires at 3-month intervals, over 12 months of follow-up in patients with IBD in clinical remission at baseline. We assessed the natural history of Rome III IBS-type symptoms over the 12 months of the study and compared psychological and quality of life data between those reporting Rome III IBS-type symptoms at each of the points of follow-up with those not reporting such symptoms.

KEY RESULTS

Among 206 patients with IBD in clinical remission at baseline (104 [50.5%] women, mean age 56.9 years [range 18-83 years], 79 [38.3%] Crohn's disease), 33 (16.0%) reported Rome III IBS-type symptoms at baseline and 72 (35.0%) reported Rome III IBS-type symptoms at one or more time points. Among the 33 patients with Rome III IBS-type symptoms at baseline, symptoms resolved in 6 (18.2%) patients, were present throughout in 6 (18.2%) patients, and fluctuated in the remaining 21 (63.6%) patients. Among the 39 patients with new onset of Rome III IBS-type symptoms after baseline, 24 (65.1%) had symptoms at one point in time only, 10 (25.6%) at two points, four (10.3%) at three points, and one (2.6%) at four points. At each point in time, reporting IBS-type symptoms was associated with significantly higher anxiety, depression, or somatoform symptom-reporting scores, and/or lower quality of life scores.

CONCLUSIONS & INFERENCES

In this 12-month follow-up study, one-third of patients with IBD reported presence of Rome III IBS-type symptoms at any point in time. Reporting such symptoms was associated with significant impacts on psychological health and/or quality of life.

α-mangostin derivatives ameliorated mouse DSS-induced chronic colitis via regulating Th17/Treg balance

Th17 cell, an important subpopulation of helper T cell, plays an important role in the development of inflammatory bowel disease (IBD) and is thought to be a potential target for the treatment of IBD. In our previous study, we demonstrated that α-mangostin could relieve lupus nephritis via inhibiting Th17 cell function. In our preliminary study, we obtained four derivatives by adding chemical modification of α-mangostin which could also inhibit Th17 cell differentiation in vitro. In this study, we constructed a chronic IBD mouse model and demonstrated the therapeutic effects of α-mangostin and its derivatives as therapeutic agents for IBD. In compounds treating groups, intestinal inflammation showed significant improvement in symptoms which included weight loss, high disease activity index, colon length shorten and the change of intestinal flora. We also found that compounds could effectively either suppress the number of Th17 cell or increase the number of Treg cell detected by flow cytometry, thus reducing the Th17/Treg ratio and suppressing the level of intestinal inflammation. Notably, IL17-F levels, rather than IL17-A, were reduced in the colon of mice of compounds treating groups. Thus, α-mangostin and its derivatives ameliorate DSS-induced chronic colitis in mice by regulating Th17/Treg balance to alleviate intestinal inflammation and can modulate the intestinal microbial community. These results suggest that α-mangostin and its derivatives may be the new therapeutic option for chronic colitis.

Deciphering the different phases of preclinical inflammatory bowel disease

Inflammatory bowel disease (IBD) is an immune-mediated inflammatory disease (IMID) of the gastrointestinal tract and includes two subtypes: Crohn's disease and ulcerative colitis. It is well-recognized that IBD is associated with a complex multifactorial aetiology that includes genetic predisposition and environmental exposures, with downstream dysregulation of systemic immune function and host-microbial interactions in the local environment in the gut. Evidence to support the notion of a multistage development of IBD is growing, as has been observed in other IMIDs such as rheumatoid arthritis and systemic lupus erythematosus. With the rising worldwide incidence of IBD, it is increasingly important to understand the complex interplay of pathological events during the different stages of disease development to enable IBD prediction and prevention strategies. In this article, we review comprehensively the current evidence pertaining to the preclinical phase of IBD, including at-risk, initiation and expansion phases. We also discuss the framework of preclinical IBD, expanding on underlying pathways in IBD development, future research directions and IBD development in the context of other IMIDs.

Global knowledge mapping and emerging research trends in the microbiome and asthma: A bibliometric and visualized analysis using VOSviewer and CiteSpace

Background

Numerous prior studies have extensively highlighted the significance of the microbiome in association with asthma. While several studies have concentrated on the asthma microbiome in previous research, there is currently a lack of publications that employ bibliometric methods to assess this area.

Methods

In this study, the Web of Science Core Collection database was utilized as the data source, and the SCI-EXPANDED index was employed to ensure that the retrieved data were comprehensive and accurate. All original research articles and review articles related to the correlation between asthma and the microbiome were systematically searched from the inception of the database until June 20, 2023. These articles were subsequently visualized and analyzed using VOSviewer and CiteSpace software.

Results

A total of 1366 relevant publications were acquired, indicating a consistent annual increase in global publications in the field. The United States and China emerged as the top two contributors to international publications. Among prolific authors, Susan V. Lynch achieved the highest publication record, with Hans Bisgaard and Jakob Stokholm sharing the second position. The majority of publications concentrated on allergy-related and microbiome areas, with a few comprehensive journals standing out. Journals with 40 or more publications included the Journal of Allergy and Clinical Immunology, Allergy, Frontiers in Immunology, and PLOS One. The top 5 cited journals were the Journal of Allergy and Clinical Immunology, PLOS One, American Journal of Respiratory and Critical Care Medicine, Clinical and Experimental Allergy, and Nature. Upon analyzing keywords, high-frequency terms, such as asthma, gut microbiota, microbiome, children, childhood asthma, allergy, risk, exposure, inflammation, diversity, and chain fatty acids emerged as representative terms in the field.

Conclusion

This study systematically presented a comprehensive overview of the literature regarding the association between asthma and the microbiome over the last two decades. Through a bibliometric perspective, the findings may assist researchers with a better understanding of the essential information in the field.

Circadian Rhythm Perturbation Aggravates Gut Microbiota Dysbiosis in Dextran Sulfate Sodium-Induced Colitis in Mice

Circadian rhythm disruption is increasingly considered an environmental risk factor for the development and exacerbation of inflammatory bowel disease. We have reported in a previous study that nychthemeral dysregulation is associated with an increase in intestinal barrier permeability and inflammation in mice with dextran sulfate sodium (DSS)-induced colitis. To investigate the effect of circadian rhythm disruption on the composition and diversity of the gut microbiota (GM), sixty male C57BL/6J mice were initially divided to two groups, with the shifted group (n = 30) exposed to circadian shifts for three months and the non-shifted group (n = 30) kept under a normal light-dark cycle. The mice of the shifted group were cyclically housed for five days under the normal 12:12 h light-dark cycle, followed by another five days under a reversed light-dark cycle. At the end of the three months, a colitis was induced by 2% DSS given in the drinking water of 30 mice. Animals were then divided into four groups (n = 15 per group): sham group non-shifted (Sham-NS), sham group shifted (Sham-S), DSS non-shifted (DSS-NS) and DSS shifted (DSS-S). Fecal samples were collected from rectal content to investigate changes in GM composition via DNA extraction, followed by high-throughput sequencing of the bacterial 16S rRNA gene. The mouse GM was dominated by three phyla: Firmicutes, Bacteroidetes and Actinobacteria. The Firmicutes/Bacteroidetes ratio decreased in mice with induced colitis. The richness and diversity of the GM were reduced in the colitis group, especially in the group with inverted circadian rhythm. Moreover, the GM composition was modified in the inverted circadian rhythm group, with an increase in Alloprevotella, Turicibacter, Bacteroides and Streptococcus genera. Circadian rhythm inversion exacerbates GM dysbiosis to a less rich and diversified extent in a DSS-induced colitis model. These findings show possible interplay between circadian rhythm disruption, GM dynamics and colitis pathogenesis.

Co-Administration of Proton Pump Inhibitors May Negatively Affect the Outcome in Inflammatory Bowel Disease Treated with Vedolizumab

Concomitant medications may alter the effect of biological therapy in inflammatory bowel disease. The aim was to investigate the effect of proton pump inhibitors on remission rates in patients with inflammatory bowel disease treated with the gut-selective vedolizumab. Patients from the Hungarian nationwide, multicenter vedolizumab cohort were selected for post hoc analysis. Primary outcomes were the assessment of clinical response and endoscopic and clinical remission at weeks 14 and 54. Secondary outcomes were the evaluation of the combined effect of concomitant steroid therapy and other factors, such as smoking, on remission. A total of 108 patients were identified with proton pump inhibitor data from 240 patients in the original cohort. Patients on steroids without proton pump inhibitors were more likely to have a clinical response at week 14 than patients on concomitant PPI (95% vs. 67%, p = 0.005). Non-smokers with IBD treated with VDZ were more likely to develop a clinical response at week 14 than smokers, particularly those not receiving PPI compared with patients on co-administered PPI therapy (81% vs. 53%, p = 0.041, and 92% vs. 74%, p = 0.029, respectively). We found that the use of PPIs in patients treated with VDZ may impair the achievement of response in certain subgroups. Unnecessary PPI prescriptions should be avoided.

Pathobionts in Inflammatory Bowel Disease: Origins, Underlying Mechanisms, and Implications for Clinical Care

The gut microbiota plays a significant role in the pathogenesis of both forms of inflammatory bowel disease (IBD), namely, Crohn's disease (CD) and ulcerative colitis (UC). Although evidence suggests dysbiosis and loss of beneficial microbial species can exacerbate IBD, many new studies have identified microbes with pathogenic qualities, termed "pathobionts," within the intestines of patients with IBD. The concept of pathobionts initiating or driving the chronicity of IBD has largely focused on the putative aggravating role that adherent invasive Escherichia coli may play in CD. However, recent studies have identified additional bacterial and fungal pathobionts in patients with CD and UC. This review will highlight the characteristics of these pathobionts and their implications for IBD treatment. Beyond exploring the origins of pathobionts, we discuss those associated with specific clinical features and the potential mechanisms involved, such as creeping fat (Clostridium innocuum) and impaired wound healing (Debaryomyces hansenii) in patients with CD as well as the increased fecal proteolytic activity (Bacteroides vulgatus) seen as a biomarker for UC severity. Finally, we examine the potential impact of pathobionts on current IBD therapies, and several new approaches to target pathobionts currently in the early stages of development. Despite recognizing that pathobionts likely contribute to the pathogenesis of IBD, more work is needed to define their modes of action. Determining whether causal relationships exist between pathobionts and specific disease characteristics could pave the way for improved care for patients, particularly for those not responding to current IBD therapies.

Post-Finasteride Syndrome And Post-Ssri Sexual Dysfunction: Two Clinical Conditions Apparently Distant, But Very Close

Post-finasteride syndrome and post-SSRI sexual dysfunction, are two poorly explored clinical conditions in which men treated for androgenetic alopecia with finasteride or for depression with SSRI antidepressants show persistent side effects despite drug suspension (e.g., sexual dysfunction, psychological complaints, sleep disorders). Because of some similarities in the symptoms, common pathological mechanisms are proposed here. Indeed, as discussed, clinical studies and preclinical data obtained so far suggest an important role for brain modulators (i.e., neuroactive steroids), neurotransmitters (i.e., serotonin, and cathecolamines), and gut microbiota in the context of the gut-brain axis. In particular, the observed interconnections of these signals in these two clinical conditions may suggest similar etiopathogenetic mechanisms, such as the involvement of the enzyme converting norepinephrine into epinephrine (i.e., phenylethanolamine N-methyltransferase). However, despite the current efforts, more work is still needed to advance the understanding of these clinical conditions in terms of diagnostic markers and therapeutic strategies.

Loss of claudin-3 expression increases colitis risk by promoting Gut Dysbiosis

Dysregulation of both the gut barrier and microbiota (dysbiosis) promotes susceptibility to and severity of Inflammatory Bowel Diseases (IBD). Leaky gut and dysbiosis often coexist; however, potential interdependence and molecular regulation are not well understood. Robust expression of claudin-3 (CLDN3) characterizes the gut epithelium, and studies have demonstrated a positive association between CLDN3 expression and gut barrier maturity and integrity, including in response to probiotics. However, the exact status and causal role of CLDN3 in IBD and regulation of gut dysbiosis remain unknown. Analysis of mouse and human IBD cohorts helped examine CLDN3 expression in IBD. The causal role was determined by modeling CLDN3 loss of expression during experimental colitis. 16S sequencing and in silico analysis helped examine gut microbiota diversity between Cldn3KO and WT mice and potential host metabolic responses. Fecal microbiota transplant (FMT) studies were performed to assess the role of gut dysbiosis in the increased susceptibility of Cldn3KO mice to colitis. A significant decrease in CLDN3 expression characterized IBD and CLDN3 loss of expression promoted colitis. 16S sequencing analysis suggested gut microbiota changes in Cldn3KO mice that were capable of modulating fatty acid metabolism and oxidative stress response. FMT from naïve Cldn3KO mice promoted colitis susceptibility in recipient germ-free mice (GFM) compared with GFM-receiving microbiota from WT mice. Our data demonstrate a critical role of CLDN3 in maintaining normal gut microbiota and inflammatory responses, which can be harnessed to develop novel therapeutic opportunities for patients with IBD.

Dextran sulfate sodium and uracil induce inflammatory effects and disrupt the chitinous peritrophic matrix in the midgut of Tribolium castaneum

Dextran sulfate sodium is used in inflammatory bowel disease (IBD) mice models to trigger chronic intestinal inflammation. In this study, we have analyzed DSS effects in the genetic model and pest beetle, Tribolium castaneum, which can be easily and cost-effectively cultivated and examined in very large quantities compensating for individual variations. We fed the larvae with DSS and uracil, which is known to induce the production of reactive oxygen species by activating DUOX, a member of the NADPH oxidase family. Both chemicals induced IBD-like phenotypes, including impaired growth and development, midgut thickening, epithelial swelling, and a loss of epithelial barrier function. RNAi mediated knockdown of DUOX expression enhanced the effects of DSS and uracil on mortality. Finally, we showed that both treatments result in an altered activity of the intestinal microbiome, similar as observed in IBD patients. Our findings suggest that both chemicals impair the epithelial barrier by increasing the permeability of the peritrophic matrix. The loss of the barrier function may facilitate the entry of midgut bacteria triggering innate immune responses that also affect the intestinal microbiome. As the observed effects resemble those induced by DSS treatment in mice, T. castaneum might be suitable high-throughput invertebrate model for IBD research and preclinical studies.

Comparison of vaginal microbiota between women with inflammatory bowel disease and healthy controls

BACKGROUND

The gut microbiota in patients with inflammatory bowel disease are perturbed in both composition and function. The vaginal microbiome and its role in the reproductive health of women with inflammatory bowel disease is less well described.

OBJECTIVE

We aim to compare the vaginal microbiota of women with inflammatory bowel disease to healthy controls.

METHODS

Women with inflammatory bowel disease enrolled in a longitudinal cohort study provided self-collected vaginal swabs. Healthy controls underwent provider-collected vaginal swabs at routine gynecologic exams. All participants completed surveys on health history, vulvovaginal symptoms and gastrointestinal symptoms, if applicable. Microbiota were characterized by sequencing the V4 region of the 16S rRNA gene. Associations between patient characteristics and microbial community composition were evaluated by PERMANOVA and Principal Components Analysis. Lactobacillus dominance of the microbial community was compared between groups using chi-square and Poisson regression.

RESULTS

The cohort included 54 women with inflammatory bowel disease (25 Ulcerative colitis, 25 Crohn's Disease) and 26 controls. A majority, 72 (90%) were White; 17 (31%) with inflammatory bowel disease and 7 (27%) controls were postmenopausal. The composition of the vaginal microbiota did not vary significantly by diagnosis or severity of inflammatory bowel disease but did vary by menopausal status (p = 0.042). There were no significant differences in Shannon Diversity Index between healthy controls and women with IBD in premenopausal participants. There was no difference in proportion of Lactobacillus dominance according to diagnosis in premenopausal participants. A subgroup of postmenopausal women with Ulcerative colitis showed a significant higher alpha diversity and a lack of Lactobacillus dominance in the vaginal microbiome.

CONCLUSIONS

Menopausal status had a larger impact on vaginal microbial communities than inflammatory bowel disease diagnosis or severity.

Cardiovascular implications of inflammatory bowel disease: An updated review

Emerging data highlights the heightened risk of atherosclerotic cardiovascular diseases (ASCVD) in patients with chronic inflammatory disorders, particularly those afflicted with inflammatory bowel disease (IBD). This review delves into the epidemiological connections between IBD and ASCVD, elucidating potential underlying mechanisms. Furthermore, it discusses the impact of current IBD treatments on cardiovascular risk. Additionally, the cardiovascular adverse effects of novel small molecule drugs used in moderate-to-severe IBD are investigated, drawing parallels with observations in patients with rheumatoid arthritis. This article aims to comprehensively evaluate the existing evidence supporting these associations. To achieve this, we conducted a meticulous search of PubMed, spanning from inception to August 2023, using a carefully selected set of keywords. The search encompassed topics related to IBD, such as Crohn's disease and ulcerative colitis, as well as ASCVD, including coronary artery disease, cardiovascular disease, atrial fibrillation, heart failure, conduction abnormalities, heart blocks, and premature coronary artery disease. This review encompasses various types of literature, including retrospective and prospective cohort studies, clinical trials, meta-analyses, and relevant guidelines, with the objective of providing a comprehensive overview of this critical intersection of inflammatory bowel disease and cardiovascular health.

Comparative Study of Intestinal Microbiome in Patients with Ulcerative Colitis and Healthy Controls in Korea

Ulcerative colitis (UC) poses a contemporary medical challenge, with its exact cause still eluding researchers. This is due to various factors, such as the rising incidence, diagnostic complexities, and difficulties associated with its management. We compared the intestinal microbiome of patients with UC to that of healthy controls to determine the qualitative and quantitative changes associated with UC that occur in the intestinal microbiota. The intestinal bacterial abundance in 40 Korean patients with UC and 25 healthy controls was assayed using via next-generation sequencing. There were five major phyla in both groups: Firmicutes (UC patients: 51.12%; healthy controls: 46.90%), Bacteroidota (UC patients: 37.04%; healthy controls: 40.34%), Proteobacteria (UC patients: 6.01%; healthy controls: 11.05%), Actinobacteriota (UC patients: 5.71%; healthy controls: 1.56%), and Desulfobacteriota (UC patients: 0.13%; healthy controls: 0.14%). Firmicutes was more prevalent in patients with UC (51.12%) compared to that of healthy controls (46.90%). Otherwise, Bacteroidota was more prevalent in healthy controls (40.34%) compared to patients with UC (37.04%). Although there was no significant difference, our results showed a substantially lower gut microbiome diversity in patients with UC (mean: 16.5; 95% confidence interval (CI) = 14.956-18.044) than in healthy controls (mean: 17.84; 95% CI = 15.989-19.691), the beta diversity and the flora structure of the microbiome in patients with UC differed from those in healthy controls. This will be helpful for the development of new treatment options and lay the groundwork for future research on UC. To understand the disease mechanism, it is essential to define the different types of microbes in the guts of patients with UC.

Characterization of the bacterial fecal microbiota composition of pigs preceding the clinical signs of swine dysentery

Swine dysentery (SD) is a worldwide production-limiting disease of growing-finishing pigs in commercial farms. The importance of the large intestinal microbiota in the swine dysentery pathogenesis has been established, but not well characterized. The objective of this study was to characterize the fecal bacterial microbiota of pigs immediately prior to developing clinical signs of swine dysentery. A total of 60 fecal samples were collected from 15 pigs with SD. Sampling times included a time point prior to SD (d0, n=15), 2 days before mucohaemorrhagic diarrhea was observed (d-2SD, n=15), 1 day before mucohaemorrhagic diarrhea was observed (d-1SD, n=15), and the day when pigs developed mucohemorragic diarrhea (MHD, n=15). Sequencing of cpn60 amplicons was used to profile the microbiome, and analyses were performed on QIIME2. Increased Chao1 index in d-1SD and MHD samples when compared to the d0 was the only change observed in alpha diversity. No differences between sampling times on beta diversity (Bray-Curtis dissimilarity) were found. Although a small sample size was investigated, differential abundance analysis revealed that Alistipes dispar and Parabacteroides gordonii were increased in MHD fecal samples when compared to d-2SD and d-1SD. It is suggested that these taxa may play a role in the pathogenesis of SD, which is known to require the presence of Brachyspira spp. and an anaerobe for severe disease development.

Microbiota-Accessible Boron-Containing Compounds in Complex Regional Pain Syndrome

The microbiota-gut-brain axis has garnered increasing attention in recent years for its role in various health conditions, including neuroinflammatory disorders like complex regional pain syndrome (CRPS). CRPS is a debilitating condition characterized by chronic neuropathic pain, and its etiology and pathophysiology remain elusive. Emerging research suggests that alterations in the gut microbiota composition and function could play a significant role in CRPS development and progression. Our paper explores the implications of microbiota in CRPS and the potential therapeutic role of boron (B). Studies have demonstrated that individuals with CRPS often exhibit dysbiosis, with imbalances in beneficial and pathogenic gut bacteria. Dysbiosis can lead to increased gut permeability and systemic inflammation, contributing to the chronic pain experienced in CRPS. B, an essential trace element, has shown promise in modulating the gut microbiome positively and exerting anti-inflammatory effects. Recent preclinical and clinical studies suggest that B supplementation may alleviate neuropathic pain and improve CRPS symptoms by restoring microbiota balance and reducing inflammation. Our review highlights the complex interplay between microbiota, inflammation, and neuropathic pain in CRPS and underscores the potential of B as a novel therapeutic approach to target the microbiota-gut-brain axis, offering hope for improved management of this challenging condition.

Orange juice containing Pediococcus acidilactici CE51 modulates the intestinal microbiota and reduces induced inflammation in a murine model of colitis

The management of inflammatory bowel diseases has been widely investigated, especially ulcerative colitis. Thus, studies with the application of new probiotic products are needed in the prevention/treatment of these clinical conditions. The objective of this work was to evaluate the effects of probiotic orange juice containing Pediococcus acidilactici CE51 in a murine model of colitis. 45 male Swiss lineage mice were used, divided into five groups (n = 9): control, colitis, colitis + probiotic (probiotic orange juice containing CE51), colitis + placebo (orange juice) and colitis + sulfasalazine (10 mg/kg/Weight). The induction of colitis was performed with dextran sodium sulfate (3%). The treatment time was 5 and 15 days after induction. Histopathological analysis, serum measurements of TNF-α and C-reactive protein and metagenomic analysis of feces were performed after euthanasia. Probiotic treatment reduced inflammation in the small intestine, large intestine and spleen. The probiotic did not alter the serum dosages of TNF-α and C-reactive protein. Their use maintained the quantitative ratio of the phylum Firmicutes/Bacteroidetes and increased Lactobacillus helveticus with 15 days of treatment (p < 0.05). The probiotic orange juice containing P. acidilactici CE51 positively modulated the gut microbiota composition and attenuated the inflammation induced in colitis.

Oxygen enrichment protects against intestinal damage and gut microbiota disturbance in rats exposed to acute high-altitude hypoxia

Acute high-altitude hypoxia can lead to intestinal damage and changes in gut microbiota. Sustained and reliable oxygen enrichment can resist hypoxic damage at high altitude to a certain extent. However, it remains unclear whether oxygen enrichment can protect against gut damage and changes in intestinal flora caused by acute altitude hypoxia. For this study, eighteen male Sprague-Dawley rats were divided into three groups, control (NN), hypobaric hypoxic (HH), and oxygen-enriched (HO). The NN group was raised under normobaric normoxia, whereas the HH group was placed in a hypobaric hypoxic chamber simulating 7,000 m for 3 days. The HO group was exposed to oxygen-enriched air in the same hypobaric hypoxic chamber as the HH group for 12 h daily. Our findings indicate that an acute HH environment caused a fracture of the crypt structure, loss of epithelial cells, and reduction in goblet cells. Additionally, the structure and diversity of bacteria decreased in richness and evenness. The species composition at Phylum and Genus level was characterized by a higher ratio of Firmicutes and Bacteroides and an increased abundance of Lactobacillus with the abundance of Prevotellaceae_NK3B31_group decreased in the HH group. Interestingly, after oxygen enrichment intervention, the intestinal injury was significantly restrained. This was confirmed by an increase in the crypt depth, intact epithelial cell morphology, increased relative density of goblet cells, and higher evenness and richness of the gut microbiota, Bacteroidetes and Prevotellaceae as the main microbiota in the HO group. Finally, functional analysis showed significant differences between the different groups with respect to different metabolic pathways, including Amino acid metabolism, energy metabolism, and metabolism. In conclusion, this study verifies, for the first time, the positive effects of oxygen enrichment on gut structure and microbiota in animals experiencing acute hypobaric hypoxia.

From nitrate to NO: potential effects of nitrate-reducing bacteria on systemic health and disease

Current research has described improving multisystem disease and organ function through dietary nitrate (DN) supplementation. They have provided some evidence that these floras with nitrate (NO3-) reductase are mediators of the underlying mechanism. Symbiotic bacteria with nitrate reductase activity (NRA) are found in the human digestive tract, including the mouth, esophagus and gastrointestinal tract (GT). Nitrate in food can be converted to nitrite under the tongue or in the stomach by these symbiotic bacteria. Then, nitrite is transformed to nitric oxide (NO) by non-enzymatic synthesis. NO is currently recognized as a potent bioactive agent with biological activities, such as vasodilation, regulation of cardiomyocyte function, neurotransmission, suppression of platelet agglutination, and prevention of vascular smooth muscle cell proliferation. NO also can be produced through the conventional L-arginine-NO synthase (L-NOS) pathway, whereas endogenous NO production by L-arginine is inhibited under hypoxia-ischemia or disease conditions. In contrast, exogenous NO3-/NO2-/NO activity is enhanced and becomes a practical supplemental pathway for NO in the body, playing an essential role in various physiological activities. Moreover, many diseases (such as metabolic or geriatric diseases) are primarily associated with disorders of endogenous NO synthesis, and NO generation from the exogenous NO3-/NO2-/NO route can partially alleviate the disease progression. The imbalance of NO in the body may be one of the potential mechanisms of disease development. Therefore, the impact of these floras with nitrate reductase on host systemic health through exogenous NO3-/NO2-/NO pathway production of NO or direct regulation of floras ecological balance is essential (e.g., regulation of body homeostasis, amelioration of diseases, etc.). This review summarizes the bacteria with nitrate reductase in humans, emphasizing the relationship between the metabolic processes of this microflora and host systemic health and disease. The potential effects of nitrate reduction bacteria on human health and disease were also highlighted in disease models from different human systems, including digestive, cardiovascular, endocrine, nervous, respiratory, and urinary systems, providing innovative ideas for future disease diagnosis and treatment based on nitrate reduction bacteria.

Diet-mediated gut microbial community modulation and signature metabolites as potential biomarkers for early diagnosis, prognosis, prevention and stage-specific treatment of colorectal cancer

BACKGROUND

Over the last decade, studies have shown an increased incidence of colorectal cancer (CRC), particularly early onset colorectal cancer (EOCRC). Researchers have demonstrated that dietary behavior, especially among young adults, influences alterations in the gut microbial community, leading to an increased accumulation of pathogenic gut microbiota and a decrease in beneficial ones. Unfortunately, CRC is likely to be diagnosed at a late stage, increasing CRC-related mortality. However, this alteration in the gut microbiota (gut dysbiosis) can be harnessed as a biomarker for non-invasive diagnosis, prognosis, prevention, and treatment of CRC in an effort to prevent late diagnosis and poor prognosis associated with CRC.

AIM OF REVIEW

This review discusses identification of potential biomarkers by targeting diet-mediated gut dysbiosis for the stage-specific diagnosis, prognosis, treatment, and prevention of CRC. Our findings provide a comprehensive insight into the potential of protumorigenic bacteria (e.g.pathogenic Escherichia coli,enterotoxigenic Bacteroides fragilis and Fusobacterium nucleatum) and their metabolites (e.g., colibactin and B. fragilis toxin) from gut dysbiosis as biomarkers for the diagnosis of CRC.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Collectively, a detailed understanding of the available data from current studies suggests that, further research on quantification of metabolites and stage-specific pathogenic microbial abundance is required for the diagnosis and treatment of CRC based on microbial dysbiosis. Specifically, future studies on faecal samples, from patient with CRC, should be conducted for F. nucleatum among different opportunistic bacteria, given its repeated occurrence in faecal samples and CRC biopsies in numerous studies. Finally, we discuss the potential of faecal microbial transplantation (FMT) as an intervention to restore damaged gut microbiota during CRC treatment and management.

Altered gut microbiota and metabolites in untreated myasthenia gravis patients

Objective

The homeostasis of the immune system is influenced by the gut microbiota. Previous studies have reported dysbiosis in the gut microbiota of myasthenia gravis (MG) patients. To investigate potential alterations in gut microbiota and metabolites in newly diagnosed and untreated MG patients, we conducted a case-control study.

Methods

Fecal samples were collected from 11 newly diagnosed and untreated MG patients as well as 11 age-and sex-matched healthy controls. These samples underwent analysis for gut microbiota using 16S ribosomal RNA (rRNA) gene sequencing, while fecal metabolome was analyzed using liquid chromatography-electrospray tandem mass spectrometry system (LC-ESI-MS/MS).

Results

The microbial community richness (observed species) and diversity (Shannon and Simpson indices) were significantly lower in the MG group compared to the control group. Microbiota composition analysis revealed significant differences between the MG and control groups at phylum, family, and genus levels. Linear discriminant analysis effect size (LEfSe) analysis showed a substantial decrease in abundance of the genus Faecalibacterium within the MG group. Fecal metabolome analysis identified three up-regulated metabolites involved in amino acid metabolism (taurine, creatinine, L-carnitine), one up-regulated metabolite involved in lipid metabolism (oleic acid), with correlation analysis indicating a positive association between Faecalibacterium abundance and creatinine levels.

Conclusion

Our findings suggest that dysbiosis already exists in newly diagnosed and untreated MG patients, implying that dysbiosis within the gut microbiota may be an initiating factor contributing to MG pathogenesis. Furthermore, F. prausnitzii may hold promise as a probiotic for treating MG.

Associations between Ileal Juice Bile Acids and Colorectal Advanced Adenoma

BACKGROUND

There is an urgent need to identify biomarkers for advanced adenoma, an important precursor of colorectal cancer (CRC). We aimed to determine alterations in ileal juice bile acids associated with colorectal advanced adenoma.

METHODS

We quantified a comprehensive panel of primary and secondary bile acids and their conjugates using an ultraperformance liquid chromatography triple-quadrupole mass spectrometric assay in ileal juice collected at colonoscopy from 46 study subjects (i.e., 14 biopsy-confirmed advanced adenomas and 32 controls free of adenoma or cancer). Using analysis of covariance (ANCOVA), we examined the differences in bile acid concentrations by disease status, adjusting for age, sex, body mass index, smoking status and type 2 diabetes.

RESULTS

The concentrations of hyodeoxycholic acid (HCA) species in ileal juice of the advanced adenoma patients (geometric mean = 4501.9 nM) were significantly higher than those of controls (geometric mean = 1292.3 nM, p = 0.001). The relative abundance of ursodeoxycholic acid (UDCA) in total bile acids was significantly reduced in cases than controls (0.73% in cases vs. 1.33% in controls; p = 0.046). No significant difference between cases and controls was observed for concentrations of total or specific primary bile acids (i.e., cholic acid (CA), chenodeoxycholic acid (CDCA) and their glycine- and taurine-conjugates) and total and specific major secondary bile acids (i.e., deoxycholic acid and lithocholic acid).

CONCLUSIONS

Colorectal advanced adenoma was associated with altered bile acids in ileal juice. The HCA species may promote the development of colorectal advanced adenoma, whereas gut microbiota responsible for the conversion of CDCA to UDCA may protect against it. Our findings have important implications for the use of bile acids as biomarkers in early detection of colorectal cancer.

Effects of urbanization and lifestyle habits on the intestinal microbiota of adolescents in eastern China

Introduction

Owing to urbanization, living habits have changed widely, leading to alterations in the intestinal microbiota of urban residents. However, there are few studies on the characteristics of intestinal microbiota of adolescents living in different urbanized areas in China.

Methods

A total of 302 fecal samples collected from adolescent students in eastern China were examined. 16S rRNA high-throughput sequencing was used to identify the fecal microbiota. These data were combined with questionnaire survey results to investigate the effect of urbanization on the intestinal microbiota of adolescents in eastern China. Moreover, the role of lifestyle habits in this relationship was also evaluated.

Results

The results revealed significant differences in the structure of the intestinal microbiota among adolescents living in regions with different levels of urbanization. Adolescents living in urban regions had a significantly higher proportion of Bacteroides (p <  0.001, FDR = 0.004), whereas those living in towns and rural regions had higher proportions of Bifidobacterium (p < 0.001, FDR < 0.001) and Prevotella (p  < 0.05, FDR = 0.019). The diversity of the intestinal microbiota was higher in urban residents than in adolescents living in towns and rural regions (p  <  0.05). In addition, the differences in intestinal microbiota across individuals living in cities, towns, and rural regions were related to dietary preferences, flavor preferences, and sleep and exercise durations. Adolescents who ate more meat had more Dorea (LDA = 3.622, p = 0.04), while the abundance of Escherichia-Shigella is higher among adolescents who ate more condiments (LDA = 4.285, p = 0.02). The abundance of Dialister was significantly increased in adolescents with longer sleep durations (LDA = 4.066, p = 0.03). Adolescents who exercised for a long duration had more Faecalibacterium than those who exercised for a shorter duration (LDA = 4.303, p = 0.04).

Discussion

Our research has preliminarily demonstrated that there were differences in the composition of Gut microbiome in stool samples of adolescents living in different urbanized areas, and provide a scientific basis for the maintenance of a healthy intentional microbota in adolescences.

Quantitative analysis of the three gut microbiota in UC and non-UC patients using real-time PCR

BACKGROUND

and study aims: Gastrointestinal microbiota are closely related to the pathogenesis of ulcerative colitis (UC). This study aimed at quantification of F. prausnitzii, Provetella, and Peptostreptococcus in UC and non-UC patients using Real-Time PCR and a new set of primers were also validated for this purpose.

MATERIALS AND METHODS

In this study, the relative abundance of microbial populations between the UC and non-UC subjects were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). DNA extraction from biopsies and polymerase chain reaction (PCR) amplification of bacterial 16S rRNA gene-targeted species-specific primers was performed to detect the anaerobic bacterial species. The qRT-PCR was used to show the relative change in the bacterial populations of F. prausnitzii, Provetella, and Peptostreptococcus in the UC and non-UC subjects.

RESULTS

Our data for detection of the anaerobic intestinal flora showed Faecalibacterium prausnitzii, Provetella and Peptostreptococcus were the predominant microflora in the controls and showed significant differences (p = 0.002, 0.025 and 0.039, respectively). The qRT-PCR analyses of F. prausnitzii, Provetella and Peptostreptococcus were 8.69-, 9.38- and 5.77-higher, respectively, in the control group than in the UC group.

CONCLUSION

The results of this study showed decreased abundance of F. prausnitzii, Provetella and Peptostreptococcus in the intestine of UC patients in comparison to non-UC patients. Quantitative RT-PCR, as a progressive and sensitive method, could be useful for evaluation of bacterial populations in patients with inflammatory bowel diseases to attain appropriate therapeutic strategies.

Safety and Potential Role of Lactobacillus rhamnosus GG Administration as Monotherapy in Ulcerative Colitis Patients with Mild-Moderate Clinical Activity

Probiotics are microorganisms that confer benefits to the host, and, for this reason, they have been proposed in several pathologic states. Specifically, probiotic bacteria have been investigated as a therapeutic option in ulcerative colitis (UC) patients, but clinical results are dishomogeneous. In particular, many probiotic species with different therapeutic schemes have been proposed, but no study has investigated probiotics in monotherapy in adequate trials for the induction of remission. Lactobacillus rhamnosus GG (LGG) is the more intensively studied probiotic and it has ideal characteristics for utilization in UC patients. The aim of the present study is to investigate the clinical efficacy and safety of LGG administration in an open trial, delivered in monotherapy at two different doses, in UC patients with mild-moderate disease. The UC patients with mild-moderate disease activity (Partial Mayo score ≥ 2) despite treatment with oral mesalamine were included. The patients stopped oral mesalamine and were followed up for one month, then were randomized to receive LGG supplement at dose of 1.2 or 2.4 × 10¹⁰ CFU/day for one month. At the end of the study, the clinical activity was evaluated and compared to that at the study entrance (efficacy). Adverse events were recorded (safety). The primary end-point was clinical improvement (reduction in the Partial Mayo score) and no serious adverse events, while the secondary end-points were the evaluation of different efficacies and safeties between the two doses of LGG. The patients with disease flares dropped out of the study and went back to standard therapy. The efficacy data were analyzed in an intention-to-treat (ITT) and per-protocol (PP) analysis. Out of the 76 patients included in the study, 75 started the probiotic therapy (n = 38 and 37 per group). In the ITT analysis, 32/76 (42%) responded to treatment, 21/76 (28%) remained stable, and 23/76 (30%) had a worsening of their clinical condition; 55 (72%) completed the treatment and were analyzed in a PP analysis: 32/55 (58%) had a clinical response, 21 (38%) remained stable, and 2 (4%) had a light worsening of their clinical condition (p < 0.0001). Overall, 37% of the patients had a disease remission. No severe adverse event was recorded, and only one patient stopped therapy due to obstinate constipation. No difference in the clinical efficacy and safety has been recorded between groups treated with different doses of LGG. The present prospective clinical trial demonstrates, for the first time, that LGG in monotherapy is safe and effective for the induction of remission in UC patients with mild-moderate disease activity (ClinicalTrials.gov identifier: NCT04102852).

Impact of Gut Microbiota on the Peripheral Nervous System in Physiological, Regenerative and Pathological Conditions

It has been widely demonstrated that the gut microbiota is responsible for essential functions in human health and that its perturbation is implicated in the development and progression of a growing list of diseases. The number of studies evaluating how the gut microbiota interacts with and influences other organs and systems in the body and vice versa is constantly increasing and several 'gut-organ axes' have already been defined. Recently, the view on the link between the gut microbiota (GM) and the peripheral nervous system (PNS) has become broader by exceeding the fact that the PNS can serve as a systemic carrier of GM-derived metabolites and products to other organs. The PNS as the communication network between the central nervous system and the periphery of the body and internal organs can rather be affected itself by GM perturbation. In this review, we summarize the current knowledge about the impact of gut microbiota on the PNS, with regard to its somatic and autonomic divisions, in physiological, regenerative and pathological conditions.

Definition of a Dietary Pattern Expressing the Intake of Vegetables and Fruits and Its Association with Intestinal Microbiota

Daily dietary habits directly or indirectly influence the intestinal microbiota, and the resulting changes in its composition and metabolic activity alter the health conditions of the host. Although many studies have analyzed the association between individual nutrients/food items and intestinal microbiota, the assessment of the diet and intestinal microbiota from a macroscopic perspective has not yet been performed in Japan. Therefore, we focused on vegetables and fruits and aimed to identify dietary patterns of high intake of these foods and to examine their relationship with the intestinal microbiota. This cross-sectional study included 1019 healthy individuals aged ≥20 years in a rural area in northern Japan. Six dietary patterns were detected by factor analysis using the brief-type self-administered diet history questionnaire (BDHQ) data to identify the "vege pattern", which was the dietary pattern rich in vegetables and fruits. Permutational multivariate analysis of variance revealed changes in β-diversity according to dietary patterns. In multivariable-adjusted models, the adherence to the vege pattern was positively correlated with α-diversity. This is the first study to reveal a correlation between intestinal microbiota and dietary habits rich in vegetables and fruits in a rural area of Japan.

Metagenomic insights into the composition and function of the gut microbiota of mice infected with Toxoplasma gondii

Introduction

Despite Toxoplasma gondii infection leading to dysbiosis and enteritis, the function of gut microbiota in toxoplasmosis has not been explored.

Methods

Here, shotgun metagenomics was employed to characterize the composition and function of mouse microbial community during acute and chronic T. gondii infection, respectively.

Results

The results revealed that the diversity of gut bacteria was decreased immediately after T. gondii infection, and was increased with the duration of infection. In addition, T. gondii infection led to gut microbiota dysbiosis both in acute and chronic infection periods. Therein, several signatures, including depression of Firmicutes to Bacteroidetes ratio and infection-enriched Proteobacteria, were observed in the chronic period, which may contribute to aggravated gut inflammation and disease severity. Functional analysis showed that a large amount of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and carbohydrate-active enzymes (CAZy) family displayed distinct variation in abundance between infected and healthy mice. The lipopolysaccharide biosynthesis related pathways were activated in the chronic infection period, which might lead to immune system imbalance and involve in intestinal inflammation. Moreover, microbial and functional spectrums were more disordered in chronic than acute infection periods, thus implying gut microbiota was more likely to participate in disease process in the chronically infected mice, even exacerbated immunologic derangement and disease progression.

Discussion

Our data indicate that the gut microbiota plays a potentially important role in protecting mice from T. gondii infection, and contributes to better understand the association between gut microbiota and toxoplasmosis.

Inhibitory effects of Clostridium butyricum culture and supernatant on inflammatory colorectal cancer in mice

Clostridium butyricum (CB) is a spore-forming, gram-positive and obligate anaerobic rod bacterium. CB can modulate the composition of the gut microbiome and promote the growth of beneficial microbes in the intestine by generating short-chain fatty acids (SCFAs), which in turn protect against colitis and prevents the formation of inflammatory-associated colorectal cancer (CRC) by ameliorating colon inflammatory processes. Yet, it remains unclear whether the culture and supernatant of CB could directly influence inflammatory CRC in mice. In this study, azoxymethane (AOM)+dextran sodium sulphate (DSS) was used to induce CRC model in C57BL/6 mice. Next, the serum levels of inflammatory cytokines, including interleukin-6 (IL-6), interleukin-10 (IL-10), and cytokines TNF-α, were measured and the pathohistological examination of the large intestine was performed. Both CB culture and supernatant were found to have anti-inflammatory properties. Subsequently, Western blot and Real-Time Quantitative PCR (RT-qPCR) revealed that CB and supernatant regulate the NF-κB/p65 pathway to inhibit the development and progression of inflammatory CRC in AOM+DSS-treated mice, which could be due to the high levels of butyric acid in the supernatant.

Identification reproducible microbiota biomarkers for the diagnosis of cirrhosis and hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a malignant tumor with high incidence in China, which is mainly related to chronic hepatitis B (CHB) and liver cirrhosis (LC) caused by hepatitis B virus (HBV) infection. This study aimed to identify reproducible gut microbial biomarkers across Chinese population for LC and HCC diagnosis. In this study, a group of 21 CHB, 25 LC, 21 HCC and 15 healthy control (HC) were examined, and used as the training data. Four published faecal datasets from different regions of China were collected, totally including 121 CHB, 33 LC, 70 HCC and 96 HC. Beta diversity showed that the distribution of community structure in CHB, LC, HCC was significantly different from HC. Correspondingly, 14 and 10 reproducible differential genera across datasets were identified in LC and HCC, respectively, defined as LC-associated and HCC-associated genera. Two random forest (RF) models based on these reproducible genera distinguished LC or HCC from HC with an area under the curve (AUC) of 0.824 and 0.902 in the training dataset, respectively, and achieved cross-region validations. Moreover, AUCs were greatly improved when clinical factors were added. A reconstructed random forest model on eight genera with significant changes between HCC and non-HCC can accurately distinguished HCC from LC. Conclusively, two RF models based on 14 reproducible LC-associated and 10 reproducible HCC-associated genera were constructed for LC and HCC diagnosis, which is of great significance to assist clinical early diagnosis.