Prevention and Alleviation of Dextran Sulfate Sodium Salt-Induced Inflammatory Bowel Disease in Mice With Bacillus subtilis-Fermented Milk via Inhibition of the Inflammatory Responses and Regulation of the Intestinal Flora

Interferon regulatory factor 7 alleviates the experimental colitis through enhancing IL-28A-mediated intestinal epithelial integrity

BACKGROUND

The incidence of inflammatory bowel disease (IBD) is on the rise in developing countries, and investigating the underlying mechanisms of IBD is essential for the development of targeted therapeutic interventions. Interferon regulatory factor 7 (IRF7) is known to exert pro-inflammatory effects in various autoimmune diseases, yet its precise role in the development of colitis remains unclear.

METHODS

We analyzed the clinical significance of IRF7 in ulcerative colitis (UC) by searching RNA-Seq databases and collecting tissue samples from clinical UC patients. And, we performed dextran sodium sulfate (DSS)-induced colitis modeling using WT and Irf7-/- mice to explore the mechanism of IRF7 action on colitis.

RESULTS

In this study, we found that IRF7 expression is significantly reduced in patients with UC, and also demonstrated that Irf7-/- mice display heightened susceptibility to DSS-induced colitis, accompanied by elevated levels of colonic and serum pro-inflammatory cytokines, suggesting that IRF7 is able to inhibit colitis. This increased susceptibility is linked to compromised intestinal barrier integrity and impaired expression of key molecules, including Muc2, E-cadherin, β-catenin, Occludin, and Interleukin-28A (IL-28A), a member of type III interferon (IFN-III), but independent of the deficiency of classic type I interferon (IFN-I) and type II interferon (IFN-II). The stimulation of intestinal epithelial cells by recombinant IL-28A augments the expression of Muc2, E-cadherin, β-catenin, and Occludin. The recombinant IL-28A protein in mice counteracts the heightened susceptibility of Irf7-/- mice to colitis induced by DSS, while also elevating the expression of Muc2, E-cadherin, β-catenin, and Occludin, thereby promoting the integrity of the intestinal barrier.

CONCLUSION

These findings underscore the pivotal role of IRF7 in preserving intestinal homeostasis and forestalling the onset of colitis.

The effects of dairy on the gut microbiome and symptoms in gastrointestinal disease cohorts: a systematic review

Bovine dairy foods provide several essential nutrients. Fermented bovine dairy foods contain additional compounds, increasing their potential to benefit gastrointestinal health. This review explores the effects of dairy consumption on the gut microbiome and symptoms in gastrointestinal disease cohorts. Human subjects with common gastrointestinal diseases (functional gastrointestinal disorders and inflammatory bowel disease) or associated symptoms, and equivalent animal models were included. A systematic literature search was performed using PubMed, Embase and Web of Science. The search yielded 3014 studies in total, with 26 meeting inclusion criteria, including 15 human studies (1550 participants) and 11 animal studies (627 subjects). All test foods were fermented bovine dairy products, primarily fermented milk and yogurt. Six studies reported increases in gastrointestinal bacterial alpha diversity, with nine studies reporting increases in relative Lactobacillus and Bifidobacterium abundance. Six studies reported increases in beneficial short-chain fatty acids, while three reported decreases. Gastrointestinal symptoms, specifically gut comfort and defecation frequency, improved in 14 human studies. Five animal studies demonstrated reduced colonic damage and improved healing. This review shows fermented bovine dairy consumption may improve gut microbial characteristics and gastrointestinal symptoms in gastrointestinal disease cohorts. Further human intervention studies are needed, expanding test foods and capturing non-self-reported gastrointestinal measures.

Probiotic characterization of Bacillus smithii: Research advances, concerns, and prospective trends

Bacillus smithii is a thermophilic Bacillus that can be isolated from white wine, hot spring soil, high-temperature compost, and coffee grounds, with various biofunctions and wide applications. It is resistant to both gastric acid and high temperature, which makes it easier to perform probiotic effects than traditional commercial probiotics, so it can maintain good vitality during food processing and has great application prospects. This paper starts with the taxonomy and genetics and focuses on aspects, including genetic transformation, functional enzyme production, waste utilization, and application in the field of food science as a potential probiotic. According to available studies during the past 30 years, we considered that B. smithii is a novel class of microorganisms with a wide range of functional enzymes such as hydrolytic enzymes and hydrolases, as well as resistance to pathogenic bacteria. It is available in waste degradation, organic fertilizer production, the feed and chemical industries, the pharmaceutical sector, and food fortification. Moreover, B. smithii has great potentials for applications in the food industry, as it presents high resistance to the technological processes that guarantee its health benefits. It is also necessary to systematically evaluate the safety, flavor, and texture of B. smithii and explore its biological mechanism of action, which is of great value for further application in multiple fields, especially in food and medicine.

The role of Lactobacillus in inflammatory bowel disease: from actualities to prospects

Inflammatory Bowel Disease (IBD), a chronic nonspecific intestinal inflammatory disease, is comprised of Ulcerative Colitis (UC) and Crohn's Disease (CD). IBD is closely related to a systemic inflammatory reaction and affects the progression of many intestinal and extraintestinal diseases. As one of the representative bacteria for probiotic-assisted therapy in IBD, multiple strains of Lactobacillus have been proven to alleviate intestinal damage and strengthen the intestinal immunological barrier, epithelial cell barrier, and mucus barrier. Lactobacillus also spares no effort in the alleviation of IBD-related diseases such as Colitis-associated Colorectal cancer (CAC), Alzheimer's Disease (AD), Depression, Anxiety, Autoimmune Hepatitis (AIH), and so on via gut-brain axis and gut-liver axis. This article aims to discuss the role of Lactobacillus in IBD and IBD-related diseases, including its underlying mechanisms and related curative strategies from the present to the future.

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.

Bifidobacterium lactis TY-S01 protects against alcoholic liver injury in mice by regulating intestinal barrier function and gut microbiota

Alcohol-induced liver injury poses a significant threat to human health. Probiotics have been proven to prevent and treat alcohol-induced liver injury. In this study, the preventive effect of Bifidobacterium lactis TY-S01 on alcohol-induced liver injury in mice was investigated. TY-S01 pretreatment effectively protected mice against alcohol-induced liver injury by preserving the levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, triglyceride and high-density lipoprotein-cholesterol in serum and maintaining the levels of the inflammatory cytokines tumor necrosis factor-α, interleukin-6 and interleukin-1β in liver tissue. Additionally, TY-S01 could maintain the endotoxin levels in serum, maintain the mRNA expression levels of zonula occluden-1, occludin, claudin-1 and claudin-3 in the gut, and prevent gut microbiota dysbiosis in mice with alcoholic liver injury. Spearman's correlation analysis revealed that there was a clear correlation among serum indicators, inflammatory cytokines and gut microbiota. In conclusion, TY-S01 attenuates alcohol-induced liver injury by protecting the integrity of the intestinal barrier and maintaining the balance of the gut microbiota.

Bifidobacterium lactis TY-S01 protects against alcoholic liver injury in mice by regulating intestinal barrier function and gut microbiota

Alcohol-induced liver injury poses a significant threat to human health. Probiotics have been proven to prevent and treat alcohol-induced liver injury. In this study, the preventive effect of Bifidobacterium lactis TY-S01 on alcohol-induced liver injury in mice was investigated. TY-S01 pretreatment effectively protected mice against alcohol-induced liver injury by preserving the levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, triglyceride and high-density lipoprotein-cholesterol in serum and maintaining the levels of the inflammatory cytokines tumor necrosis factor-α, interleukin-6 and interleukin-1β in liver tissue. Additionally, TY-S01 could maintain the endotoxin levels in serum, maintain the mRNA expression levels of zonula occluden-1, occludin, claudin-1 and claudin-3 in the gut, and prevent gut microbiota dysbiosis in mice with alcoholic liver injury. Spearman's correlation analysis revealed that there was a clear correlation among serum indicators, inflammatory cytokines and gut microbiota. In conclusion, TY-S01 attenuates alcohol-induced liver injury by protecting the integrity of the intestinal barrier and maintaining the balance of the gut microbiota.

Carbon dots induce pathological damage to the intestine via causing intestinal flora dysbiosis and intestinal inflammation

BACKGROUND

Carbon dots (CDs), as excellent antibacterial nanomaterials, have gained great attention in treating infection-induced diseases such as periodontitis and stomatitis. Given the eventual exposure of CDs to the intestine, elucidating the effect of CDs on intestinal health is required for the safety evaluation of CDs.

RESULTS

Herein, CDs extracted from ε-poly-L-lysine (PL) were chosen to explore the modulation effect of CDs on probiotic behavior in vitro and intestinal remodeling in vivo. Results verify that PL-CDs negatively regulate Lactobacillus rhamnosus (L. rhamnosus) growth via increasing reactive oxygen species (ROS) production and reducing the antioxidant activity, which subsequently destroys membrane permeability and integrity. PL-CDs are also inclined to inhibit cell viability and accelerate cell apoptosis. In vivo, the gavage of PL-CDs is verified to induce inflammatory infiltration and barrier damage in mice. Moreover, PL-CDs are found to increase the Firmicutes to Bacteroidota (F/B) ratio and the relative abundance of Lachnospiraceae while decreasing that of Muribaculaceae.

CONCLUSION

Overall, these evidences indicate that PL-CDs may inevitably result in intestinal flora dysbiosis via inhibiting probiotic growth and simultaneously activating intestinal inflammation, thus causing pathological damage to the intestine, which provides an effective and insightful reference for the potential risk of CDs from the perspective of intestinal remodeling.

Disturbances of the Gut Microbiota and Microbiota-Derived Metabolites in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), is characterized as a chronic and recurrent inflammatory disease whose pathogenesis is still elusive. The gut microbiota exerts important and diverse effects on host physiology through maintaining immune balance and generating health-benefiting metabolites. Many studies have demonstrated that IBD is associated with disturbances in the composition and function of the gut microbiota. Both the abundance and diversity of gut microbiota are dramatically decreased in IBD patients. Furthermore, some particular classes of microbiota-derived metabolites, principally short-chain fatty acids, tryptophan, and its metabolites, and bile acids have also been implicated in the pathogenesis of IBD. In this review, we aim to define the disturbance of gut microbiota and the key classes of microbiota-derived metabolites in IBD pathogenesis. In addition, we also focus on scientific evidence on probiotics, not only on the molecular mechanisms underlying the beneficial effects of probiotics on IBD but also the challenges it faces in safe and appropriate application.

Cow’s milk-induced gastrointestinal disorders: From infancy to adulthood

Milk is related to many gastrointestinal disorders from the cradle to the grave due to the many milk ingredients that can trigger gastrointestinal discomfort and disorders. Cow’s milk protein allergy (CMPA) is the most common food allergy, especially in infancy and childhood, which may persist into adulthood. There are three main types of CMPA; immunoglobulin E (IgE)-mediated CMPA, non-IgE-mediated CMPA, and mixed type. CMPA appears before the first birthday in almost all cases. Symptoms may start even during the neonatal period and can be severe enough to simulate neonatal sepsis. CMPA (often non-IgE mediated) can present with symptoms of gastroesophageal reflux, eosinophilic esophagitis, hemorrhagic gastritis, food protein-induced protein-losing enteropathy, and food protein-induced enterocolitis syndrome. Most CMPAs are benign and outgrown during childhood. CMPA is not as common in adults as in children, but when present, it is usually severe with a protracted course. Lactose intolerance is a prevalent condition characterized by the development of many symptoms related to the consumption of foods containing lactose. Lactose intolerance has four typical types: Developmental, congenital, primary, and secondary. Lactose intolerance and CMPA may be the underlying pathophysiologic mechanisms for many functional gastrointestinal disorders in children and adults. They are also common in inflammatory bowel diseases. Milk consumption may have preventive or promoter effects on cancer development. Milk may also become a source of microbial infection in humans, causing a wide array of diseases, and may help increase the prevalence of antimicrobial resistance. This editorial summarizes the common milk-related disorders and their symptoms from childhood to adulthood.

Nattokinase enhances the preventive effects of Escherichia coli Nissle 1917 on dextran sulfate sodium-induced colitis in mice

Nattokinase with excellent anti-thrombotic, anti-inflammatory, anti-tumor, and anti-hypertension properties has been used in the development of several healthcare products in many countries. The probiotic Escherichia coli Nissle 1917 (EcN) with anti-inflammatory effect is commonly used to treat inflammatory bowel disease. To determine whether nattokinase could enhance the therapeutic efficacy of EcN in colitis, a recombinant E. coli Nissle 1917 strain (EcNnatto) with nattokinase-expressing ability was successfully constructed, and the protective effect of the engineered strain on mice with experimental chronic colitis was investigated. Although both EcN and EcNnatto strains substantially alleviated the clinical symptoms and pathological abnormalities in colitis mice by regulating gut flora and maintaining intestinal barrier function, the EcNnatto strain was found to perform better than the control strain, based on a further increase in colon length and a downregulation in pro-inflammatory cytokines (IL-6 and TNF-α). Nattokinase expressed in EcN attenuated DSS-induced epithelial damage and restored the mucosal integrity by upregulating the levels of tight junction proteins, including ZO-1 and occludin. The expression level of Lgr5, a marker of intestinal stem cells, was also increased. Moreover, constitutively expressed nattokinase in EcN reversed the gut microbial richness and diversity in colitis mice. Based on our findings, nattokinase could strengthen the capacity of EcN to treat intestinal inflammation.

Effects of lactic acid bacteria-fermented formula milk supplementation on ileal microbiota, transcriptomic profile, and mucosal immunity in weaned piglets

BACKGROUND

Lactic acid bacteria (LAB) participating in milk fermentation naturally release and enrich the fermented dairy product with a broad range of bioactive metabolites, which has numerous roles in the intestinal health-promoting of the consumer. However, information is lacking regarding the application prospect of LAB fermented milk in the animal industry. This study investigated the effects of lactic acid bacteria-fermented formula milk (LFM) on the growth performance, intestinal immunity, microbiota composition, and transcriptomic responses in weaned piglets. A total of 24 male weaned piglets were randomly divided into the control (CON) and LFM groups. Each group consisted of 6 replicates (cages) with 2 piglets per cage. Each piglet in the LFM group were supplemented with 80 mL LFM three times a day, while the CON group was treated with the same amount of drinking water.

RESULTS

LFM significantly increased the average daily gain of piglets over the entire 14 d (P < 0.01) and the average daily feed intake from 7 to 14 d (P < 0.05). Compared to the CON group, ileal goblet cell count, villus-crypt ratio, sIgA, and lactate concentrations in the LFM group were significantly increased (P < 0.05). Transcriptomic analysis of ileal mucosa identified 487 differentially expressed genes (DEGs) between two groups. Especially, DEGs involved in the intestinal immune network for IgA production pathways, such as polymeric immunoglobulin receptor (PIGR), were significantly up-regulated (P < 0.01) by LFM supplementation. Moreover, trefoil factor 2 (TFF2) in the LFM group, one of the DEGs involved in the secretory function of goblet cells, was also significantly up-regulated (P < 0.01). Sequencing of the 16S rRNA gene of microbiota demonstrated that LFM led to selective enrichment of lactate-producing and short-chain fatty acid (SCFA)-producing bacteria in the ileum, such as an increase in the relative abundance of Enterococcus (P = 0.09) and Acetitomaculum (P < 0.05).

CONCLUSIONS

LFM can improve intestinal health and immune tolerance, thus enhancing the growth performance of weaned piglets. The changes in microbiota and metabolites induced by LFM might mediate the regulation of the secretory function of goblet cells.

Peptides, Exopolysaccharides, and Short-Chain Fatty Acids from Fermented Milk and Perspectives on Inflammatory Bowel Diseases

Crohn's disease and ulcerative colitis are characterized by chronic inflammatory processes and an imbalanced immune response along the gastrointestinal (GI) tract. Pharmacological treatments have been widely used, although their long-term application has adverse side effects. On the other hand, milks fermented with specific lactic acid bacteria (LAB) have been shown to be useful as alternative or complementary aids. Many metabolites such as peptides, exopolysaccharides, and short-chain fatty acids are produced during milk fermentation. These components have been shown to change the pH of the gastrointestinal lumen, aid intestine mucosal recovery, modulate the microbiota, and reduce the inflammatory response (innate and adaptive immune system), both in vitro and in vivo. Therefore, the objective of the present review is to describe how these bioactive compounds from fermented milk by specific LAB can decrease the deleterious symptoms of inflammatory bowel disease.

Regulation of gut microbiota-bile acids axis by probiotics in inflammatory bowel disease

Inflammatory bowel disease (IBD) is characterized by chronic and relapsing inflammation of gastrointestinal tract, with steadily increased incidence and prevalence worldwide. Although the precise pathogenesis remains unclear, gut microbiota, bile acids (BAs), and aberrant immune response play essential roles in the development of IBD. Lately, gut dysbiosis including certain decreased beneficial bacteria and increased pathogens and aberrant BAs metabolism have been reported in IBD. The bacteria inhabited in human gut have critical functions in BA biotransformation. Patients with active IBD have elevated primary and conjugated BAs and decreased secondary BAs, accompanied by the impaired transformation activities (mainly deconjugation and 7α-dehydroxylation) of gut microbiota. Probiotics have exhibited certain positive effects by different mechanisms in the therapy of IBD. This review discussed the effectiveness of probiotics in certain clinical and animal model studies that might involve in gut microbiota-BAs axis. More importantly, the possible mechanisms of probiotics on regulating gut microbiota-BAs axis in IBD were elucidated, which we focused on the elevated gut bacteria containing bile salt hydrolase or BA-inducible enzymes at genus/species level that might participate in the BA biotransformation. Furthermore, beneficial effects exerted by activation of BA-activated receptors on intestinal immunity were also summarized, which might partially explain the protect effects and mechanisms of probiotics on IBD. Therefore, this review will provide new insights into a better understanding of probiotics in the therapy targeting gut microbiota-BAs axis of IBD.

The role of intestinal stem cell within gut homeostasis: Focusing on its interplay with gut microbiota and the regulating pathways

Intestinal stem cells (ISCs) play an important role in maintaining intestinal homeostasis via promoting a healthy gut barrier. Within the stem cell niche, gut microbiota linking the crosstalk of dietary influence and host response has been identified as a key regulator of ISCs. Emerging insights from recent research reveal that ISC and gut microbiota interplay regulates epithelial self-renewal. This article reviews the recent knowledge on the key role of ISC in their local environment (stem cell niche) associating with gut microbiota and their metabolites as well as the signaling pathways. The current progress of intestinal organoid culture is further summarized. Subsequently, the key challenges and future directions are discussed.

Probiotics Interact With Lipids Metabolism and Affect Gut Health

Probiotics have attracted much attention due to their ability to modulate host intestinal microbe, participate in nutrient metabolism or immunomodulatory. Both inflammatory bowel disease (IBD) and bowel cancer are digestive system disease, which have become a global public health problem due to their unclear etiology, difficult to cure, and repeated attacks. Disturbed gut microbiota and abnormal lipid metabolism would increase the risk of intestinal inflammation. However, the link between lipid metabolism, probiotics, and IBD is unclear. In this review, we found that different lipids and their derivatives have different effects on IBD and gut microbes. ω-3 polyunsaturated fatty acids (PUFAs) docosahexaenoic acid, eicosapentaenoic acid, and their derivatives resolvin E1, resolvin D can inhibit oxidative stress and reactive oxygen species activate NFκB and MAPk pathway. While ω-6 PUFAs linoleic acid and arachidonic acid can be derived into leukotrienes and prostaglandins, which will aggravate IBD. Cholesterol can be converted into bile acids to promote lipid absorption and affect microbial survival and colonization. At the same time, it is affected by microbial bile salt hydrolase to regulate blood lipids. Low denstiy lipoprotein (LDL) is easily converted into oxidized LDL, thereby promoting inflammation, while high denstiy lipoprotein (HDL) has the opposite effect. Probiotics compete with intestinal microorganisms for nutrients or ecological sites and thus affect the structure of intestinal microbiota. Moreover, microbial short chain fatty acids, bile salt hydrolase, superoxide dismutase, glutathione, etc. can affect lipid metabolism and IBD. In conclusion, probiotics are directly or indirectly involved in lipids metabolism and their impact on IBD, which provides the possibility to explore the role of probiotics in improving gut health.

Mucosa-Colonizing Microbiota Correlate With Host Autophagy Signaling in Patients With Inflammatory Bowel Disease

Both bacteria and autophagy are implicated in inflammatory bowel disease (IBD) pathogenesis. However, how bacteria crosstalk with autophagy signaling remains largely known, especially in intestinal mucosa. This study aimed to profile the internal complex autophagy signaling cascade and their external correlation with these bacteria, and consequently provide a systematic and precise target for future IBD diagnosis and therapy. We found the Ulcerative colitis (UC) patients exhibited more severe dysbiosis than the Crohn’s disease (CD) patients, as represented by alpha diversity, community phenotypes, and functional annotation compared with the control population. Meanwhile, CD patients showed greater transcriptional signaling activities of autophagy, endoplasmic reticulum (ER) stress, and bile acid production. Dominant bacteria (e.g., Rhodococcus, Escherichia, Shigella, and Enterococcus) were positively correlated and low-abundance bacteria (e.g., Bacillus, Acidovorax, Acinetobacter, and Stenotrophomonas) were negatively correlated with the autophagy signaling cascade (184 autophagy genes, 52 ER stress genes, and 22 bile acid production genes). Our observations suggested UC patients showed temporary and widespread microbiota turbulence and CD patients showed processive and local autophagy activity during IBD progression. Intestinal mucosa-colonizing bacteria were correlated with the bile/ER stress/autophagy signaling axis in IBD pathogenesis.

Strains producing different short-chain fatty acids alleviate DSS-induced ulcerative colitis by regulating intestinal microecology

B. bifidum H3-R2, P. freudenreichii B1 and C. butyricum C1-6 exert protective effects against DSS-induced UC in mice by modulating inflammatory factors, intestinal barrier, related signalling pathways, gut microbiome and SCFAs levels.

Probiotic Bacillus cereus Alleviates Dextran Sulfate Sodium-Induced Colitis in Mice through Improvement of the Intestinal Barrier Function, Anti-Inflammation, and Gut Microbiota Modulation

Dysbiosis leads to continuous progress of inflammatory bowel disease (IBD). However, current therapeutic approaches for IBD have limited efficacy and are associated with various side effects. This study focused on exploring the positive effect of a new Bacillus cereus (B. cereus) strain (HMPM18123) in a colitis mouse model and elucidate the underlying molecular mechanisms. The colitis symptoms were alleviated by the B. cereus administration as evidenced by decreased body weight loss, colon length shortening, disease activity index score, and histopathological score. The B. cereus mitigated intestinal epithelial barrier damage by upregulating tight junction protein expression. Moreover, B. cereus exerted anti-inflammatory effects by regulating macrophage polarization and suppressing the TLR4-NF-κB-NLRP3 inflammasome signaling pathways. B. cereus also rebalanced the damaged gut microbiota. Thus, the molecular mechanism of alleviating colitis by B. cereus treatment involved the regulation of the TLR4-NF-κB-NLRP3 inflammasome signaling pathways in intestinal mucosal barriers by modulating gut microbiota composition.

Serum Untargeted Metabolism Reveals the Mechanism of L. plantarum ZDY2013 in Alleviating Kidney Injury Induced by High-Salt Diet

A high-salt diet (HSD) is one of the key risk factors for hypertension and kidney injury. In this study, a HSD C57BL/6J mice model was established with 4% NaCl, and then different concentrations of Lactobacillus plantarum ZDY2013 were intragastrically administered for 2 weeks to alleviate HSD-induced renal injury. For the study, 16S rRNA gene sequencing, non-targeted metabonomics, real-time fluorescent quantitative PCR, and Masson’s staining were used to investigate the mechanism of L. plantarum ZDY2013 in alleviating renal damage. Results showed that HSD caused intestinal inflammation and changed the intestinal permeability of mice, disrupted the balance of intestinal flora, and increased toxic metabolites (tetrahydrocorticosteron (THB), 3-methyhistidine (3-MH), creatinine, urea, and L-kynurenine), resulting in serious kidney damage. Interestingly, L. plantarum ZDY2013 contributed to reconstructing the intestinal flora of mice by increasing the level of Lactobacillus and Bifidobacterium and decreasing that of Prevotella and Bacteroides. Moreover, the reconstructed intestinal microbiota significantly changed the concentration of the metabolites of hosts through metabolic pathways, including TCA cycle, ABC transport, purine metabolism, and histidine metabolism. The content of uremic toxins such as L-kynurenine, creatinine, and urea in the serum of mice was found to be decreased by L. plantarum ZDY2013, which resulted in renal injury alleviation. Our data suggest that L. plantarum ZDY2013 can indeed improve chronic kidney injury by regulating intestinal flora, strengthening the intestinal barrier, limiting inflammatory response, and reducing uremic toxins.

Synergistic Protective Effect of Konjac Mannan Oligosaccharides and Bacillus subtilis on Intestinal Epithelial Barrier Dysfunction in Caco-2 Cell Model and Mice Model of Lipopolysaccharide Stimulation

As the first line of defense against intestinal bacteria and toxins, intestinal epithelial cells are always exposed to bacteria or lipopolysaccharide (LPS), whereas pathogenic bacteria or LPS can cause intestinal epithelial cell damage. Previous studies have shown that konjac mannan oligosaccharides (KMOS) have a positive effect on maintaining intestinal integrity, and Bacillus subtilis (BS) can promote the barrier effect of the intestine. However, it is still unknown whether KMOS and BS have a synergistic protective effect on the intestines. In this study, we used the LPS-induced Caco-2 cell injury model and mouse intestinal injury model to study the synergistic effects of KMOS and BS. Compared with KMOS or BS alone, co-treatment with KMOS and BS significantly enhanced the activity and antioxidant capacity of Caco-2 cell, protected mouse liver and ileum from LPS-induced oxidative damage, and repaired tight junction and mucus barrier damage by up-regulating the expression of Claudin-1, ZO-1 and MUC-2. Our results demonstrate that the combination of KMOS and BS has a synergistic repair effect on inflammatory and oxidative damage of Caco-2 cells and aIIeviates LPS-induced acute intestinal injury in mice.

Gut Microbiota and Dietary Factors as Modulators of the Mucus Layer in Inflammatory Bowel Disease

The gastrointestinal tract is optimized to efficiently absorb nutrients and provide a competent barrier against a variety of lumen environmental compounds. Different regulatory mechanisms jointly collaborate to maintain intestinal homeostasis, but alterations in these mechanisms lead to a dysfunctional gastrointestinal barrier and are associated to several inflammatory conditions usually found in chronic pathologies such as inflammatory bowel disease (IBD). The gastrointestinal mucus, mostly composed of mucin glycoproteins, covers the epithelium and plays an essential role in digestive and barrier functions. However, its regulation is very dynamic and is still poorly understood. This review presents some aspects concerning the role of mucus in gut health and its alterations in IBD. In addition, the impact of gut microbiota and dietary compounds as environmental factors modulating the mucus layer is addressed. To date, studies have evidenced the impact of the three-way interplay between the microbiome, diet and the mucus layer on the gut barrier, host immune system and IBD. This review emphasizes the need to address current limitations on this topic, especially regarding the design of robust human trials and highlights the potential interest of improving our understanding of the regulation of the intestinal mucus barrier in IBD.

Correlation Between Sleep, Life, Mood, and Diet and Severity of Inflammatory Bowel Disease in China: A Retrospective Study

Background

The aim of the present study was to assess the relationship between inflammatory bowel disease (IBD) and quality of sleep, quality of life (QoL), mental health, and dietary intake to identify potential risk factors for IBD.

Material/Methods

This was a retrospective analysis from September 2019 to August 2020. We enrolled 71 patients with IBD aged 14 to 69 years who completed the IBD-Life Habits Questionnaire, which included data on demographics, environmental factors, and dietary habits; the Pittsburgh Sleep Quality Index (PSQI); Patient Health Questionnaire (PHQ-9); Generalized Anxiety Disorder-7 (GAD-7); and the Inflammatory Bowel Disease Questionnaire (IBDQ). Of the patients, 46 had IBD that was in remission and in 25 the disease was active, based on scores used to assess clinical symptoms. The Crohn’s Disease Activity Index (CDAI) and the Partial Mayo Score were used for Crohn disease (CD) and ulcerative colitis (UC), respectively.

The patients were divided into 2 groups, based on disease status: remission (CDAI <150 or Mayo Score=0) and active (CDAI ≥150 or Mayo Score >0). Because sleep and dietary habits in the patients with UC and CD were not significantly different, the 2 groups of patients were eventually combined into a single IBD group. The IBD-Life Habits Questionnaire, except for IBDQ, was completed by 68 age- and sex-matched healthy controls.

Results

Scores for PSQI (P=.001), PHQ-9 (P=.003), GAD-7 (P=.007), and IBDQ (P=.001) were significantly higher in the patients with active IBD. An IBDQ score >168.0 (PSQI score >7.5) indicates a clinically active state of IBD with a sensitivity of 84.8% (72.0%) and a specificity of 88.0% (82.6%). Diet composition was not related to disease activity. An analysis of patients and controls showed that lack of siblings could be a protective factor for onset of IBD (OR 0.300, 95% CI 0.119–0.785), while not being breastfed (OR 2.753, 95% CI 1.025–7.396) and consuming spicy foods could be risk factors for onset of IBD (OR 2.186, 95% CI 1.370–3.488).

Conclusions

In patients with IBD, poor sleep quality, poor QoL, depression, and anxiety were related to having active disease, whereas diet was not. Attempting to control dietary composition in patients with IBD may not be effective in preventing disease flare, but attention should be paid to intake of spicy foods.