Genetic and environmental factors shape the host response to Helicobacter hepaticus: insights into IBD pathogenesis

Probiotic Mixture Attenuates Colorectal Tumorigenesis in Murine AOM/DSS Model by Suppressing STAT3, Inducing Apoptotic p53 and Modulating Gut Microbiota

Colorectal cancer (CRC) is one of the most common cancers worldwide. The standard CRC chemo drug, 5-Fluorouracil (5-FU), has a poor response rate and chemoresistance, prompting the need for a more effective and affordable treatment. In this study, we aimed to evaluate whether Prohep, a novel probiotic mixture, would alleviate azoxymethane/dextran sodium sulfate (AOM/DSS)-induced colorectal tumorigenesis and enhance 5-FU efficacy and its mechanism. Our results suggested that Prohep showed stronger anti-tumorigenesis effects than 5-FU alone or when combined in the AOM/DSS model. Prohep significantly reduced the total tumor count, total tumor size, caecum weight, colonic crypt depth, colonic inflammation, and collagen fibrosis. Prohep downregulated pro-inflammatory TNF-α and proliferative p-STAT3 and upregulated apoptotic p53. Metagenomics analysis indicated that Prohep-enriched Helicobacter ganmani, Desulfovibrio porci, Helicobacter hepaticus, and Candidatus Borkfalkia ceftriaxoniphila were inversely correlated to the total tumor count. In addition, Prohep-enriched Prevotella sp. PTAC and Desulfovibrio porci were negatively correlated to AOM/DSS enriched bacteria, while forming a co-existing community with other beneficial bacteria. From KEGG analysis, Prohep downregulated CRC-related pathways and enhanced pathways related to metabolites suppressing CRC like menaquinone, tetrapyrrole, aminolevulinic acid, and tetrahydrofolate. From Metacyc analysis, Prohep downregulated CRC-related peptidoglycan, LPS, and uric acid biosynthesis, and conversion. Prohep elevated the biosynthesis of the beneficial L-lysine, lipoic acid, pyrimidine, and palmitate. Prohep also elevated metabolic pathways related to energy utilization of lactic acid-producing bacteria (LAB) and acetate producers. Similarly, fecal acetate concentration was upregulated by Prohep. To sum up, Prohep demonstrated exceptional anti-tumorigenesis effects in the AOM/DSS model, which revealed its potential to develop into a novel CRC therapeutic in the future.

Protective effect of a newly probiotic Lactobacillus reuteri LY2-2 on DSS-induced colitis

PURPOSE

This study aimed to investigate the role of a newly isolated strain L.reuteri LY2-2 in colitis in mice and explored the underlying mechanisms. METHODS L.

REUTERI

LY2-2 was orally administered to mice with dextran sulfate sodium (DSS)-induced colitis. 5-Aminosalicylic acid (5-ASA) treatment was used as the drug control.

RESULTS

The results showed that the disease severity of colitis mice was significantly alleviated. The intestinal inflammation was restricted by synergistically reducing pro-inflammatory cytokines, inhibiting TLR4-NF-κB signaling, restoring the abnormal immune response, and enhancing intestinal barrier function. Of note, L.reuteri LY2-2 showed great potential in modulating macrophages polarization in colonic tissues. Moreover, the gut dysbiosis was improved. The potentially pro-inflammatory pathogenic bacteria such as Helicobacter and Romboutsia decreased and the probiotics including L.rhamnosus and L.plantarum increased. Interestingly, the above pathological indexes in the L.reuteri LY2-2 group were better than those in the 5-ASA group.

CONCLUSION

L.reuteri LY2-2 had a better protective effect on DSS-induced colitis via its anti-inflammatory and microbiota-balancing properties, which supports the potential value of this probiotic against colitis. These results contribute to product development of functional probiotics for colitis and provide valuable insights for their mechanisms of biological function to affect human health status.

Pristimerin Alleviates DSS-Induced Colitis in Mice by Modulating Intestinal Barrier Function, Gut Microbiota Balance and Host Metabolism

Pristimerin is a pentacyclic triterpenoid mainly derived from Celastraceae plants such as Maytenus ilicifolia, which has been traditionally used for the treatment of gastrointestinal disorders. Pharmacological studies have shown that pristimerin exhibited anti-inflammatory, antioxidant, anticancer and antibacterial activities. However, the potential mechanism of pristimerin for the treatment of ulcerative colitis (UC) remains elusive. In the present study, pristimerin could effectively inhibit the NO generation induced by LPS in RAW 264.7 cells and upregulate the decreased expression of tight junction proteins such as occludin and claudin-1. In vivo, oral administration of pristimerin (0.5 mg/kg and 1 mg/kg) could significantly relieve UC symptoms such as body weight loss, disease activity index, shortened colon length and colonic pathological damage. Meanwhile, pristimerin decreased the TNF-α, MPO and MDA levels and increased the levels of IL-10, IL-22, SOD activity, occludin and claudin-1 in colon tissues. Gut microbiota analysis of cecum contents revealed that pristimerin treatment effectively alleviated gut microbiota dysbiosis. Additionally, serum metabolomics showed that 33 potential biomarkers involving lipid and tryptophan metabolism were identified, which may account for the therapeutic effects of pristimerin on UC mice. In conclusion, our findings indicate that pristimerin attenuates UC symptoms in DSS-induced mice through modulating intestinal barrier integrity, gut microbiota composition, lipid and tryptophan metabolism.

Preparation Process Optimization of Glycolipids from Dendrobium officinale and the Difference in Antioxidant Effects Compared with Ascorbic Acid

Background:Dendrobium officinale glycolipids (DOG), often left as residues after hot water extraction for polysaccharide production, are often discarded.

METHODS

This study investigates the optimal extraction of DOG using response surface methodology, focusing on liquid-solid ratios, ethanol concentrations, extraction temperatures, and extraction times, while preliminarily analyzing DOG's structural properties. Additionally, the differences in antioxidant effects between DOG and ascorbic acid based on intestinal flora metabolism were further evaluated.

RESULTS

The optimal parameters for DOG extraction were determined as follows: liquid-solid ratio of 20 mL/g, ethanol concentration of 70%, extraction temperature of 70 °C, and extraction time of 2.5 h, yielding 2.64 ± 0.18%. In addition, DOG was identified as a diglyceride, mainly composed of glucose, mannose, linoleic acid, 9,12,15-octadecatrienoic acid, and presented certain direct free radicals scavenging effects. In animal experiments, unlike the direct free scavenging effects of ascorbic acid, DOG increased intestinal Bacteroides acidifaciens abundance in mice, up-regulated piceatannol expression, and down-regulated 1-naphthol expression, which contributed to antioxidant effects by enhancing the activities of SOD and GSH-Px while reducing MDA content.

CONCLUSIONS

DOG was a diglyceride isolated from D. officinale residues after hot water extraction, and presented strong antioxidant effects by regulating intestinal flora metabolism. These findings could promote the efficient utilization of D. officinale and support further development of DOG in functional food applications.

Classification of cancer types based on microRNA expression using a hybrid radial basis function and particle swarm optimization algorithm

The diagnosis and treatment of cancer is one of the most challenging aspects of the medical profession, despite advances in disease diagnosis. MicroRNAs are small noncoding RNA molecules involved in regulating gene expression and are associated with several cancer types. Therefore, the analysis of microRNA data has become one of the most important areas of cancer research in recent years. This paper presents an improved method for cancer-type classification based on microRNA expression data using a hybrid radial basis function (RBF) and particle swarm optimization (PSO) algorithm. Two datasets containing microRNA information were used, and preprocessing and normalization operations were performed on the raw data. Feature selection was carried out by using the PSO algorithm, which can identify the most relevant and informative features in the data along with helping to prioritize them. Using a PSO algorithm for feature selection is an effective approach to microRNA analysis. This enhances the accuracy and reliability of cancer-type classifications based on microRNA expression data. In the proposed method, we, respectively, achieved an accuracy of 0.95% and 0.91% on both datasets, with an average of 0.93%, using an improved RBF neural network classifier. These results demonstrate that the proposed method outperforms previous works. RESEARCH HIGHLIGHTS: To enhance the accuracy of cancer-type classifications based on microRNA expression data. We present a minimal feature selection method using particle swarm optimization to reduce computational load & radial basis function to improve accuracy.

Crude Tieguanyin oolong tea polysaccharides regulate intestinal immune and gut microflora in dextran sulfate sodium-induced mice colitis

BACKGROUND

The global incidence and prevalence of inflammatory bowel diseases (IBDs) have been increasing. Epidemiological studies, clinical trials, and animal experiments have indicated a negative association between the consumption of tea and IBD. This study aims to investigate the protective effects of crude Tieguanyin oolong tea polysaccharides (CTPS) on experimental colitis, while also exploring the underlying mechanisms.

RESULTS

The administration of CTPS significantly alleviated IBD in the mouse model, and was found to regulate T-cell mediated immune responses in the colon by modulating cytokine production associated with T cells. Furthermore, CTPS demonstrated a positive impact on the gut microbiota, reversing the increase in pathogenic Helicobacter and enhancing the relative abundances of beneficial bacteria such as Akkermansia, Lachnospiraceae, and Odoribacter. Oral administration of CTPS also led to an improvement in intestinal metabolism, specifically by increasing the levels of short-chain fatty acids.

CONCLUSION

This study provides the first in vivo evidence of the protective effects of CTPS on colitis in mice. The effects are likely facilitated through the regulation of T cell-mediated responses and modulation of the gut microbiota, suggesting that CTPS may be a potential preventive and therapeutic approach for IBD. © 2023 Society of Chemical Industry.

Effect of a multi-strain probiotic mixture consumption on anxiety and depression symptoms induced in adult mice by postnatal maternal separation

BACKGROUND

Intestinal microbial composition not only affects the health of the gut but also influences centrally mediated systems involved in mood, through the "gut-brain" axis, a bidirectional communication between gut microbiota and the brain. In this context, the modulation of intestinal microbiota and its metabolites through the administration of probiotics seems to represent a very promising approach in the treatment of the central nervous system alterations. Early postnatal life is a critical period during which the brain undergoes profound and essential modulations in terms of maturation and plasticity. Maternal separation (MS), i.e., the disruption of the mother-pup interaction, represents a pivotal paradigm in the study of stress-related mood disorders, by inducing persistent changes in the immune system, inflammatory processes, and emotional behavior in adult mammals.

RESULTS

We conducted experiments to investigate whether sustained consumption of a multi-strain probiotic formulation by adult male mice could mitigate the effects of maternal separation. Our data demonstrated that the treatment with probiotics was able to totally reverse the anxiety- and depressive-like behavior; normalize the neuro-inflammatory state, by restoring the resting state of microglia; and finally induce a proneurogenic effect. Mice subjected to maternal separation showed changes in microbiota composition compared to the control group that resulted in permissive colonization by the administered multi-strain probiotic product. As a consequence, the probiotic treatment also significantly affected the production of SCFA and in particular the level of butyrate.

CONCLUSION

Gut microbiota and its metabolites mediate the therapeutic action of the probiotic mix on MS-induced brain dysfunctions. Our findings extend the knowledge on the use of probiotics as a therapeutic tool in the presence of alterations of the emotional sphere that significantly impact on gut microbiota composition. Video Abstract.

Akkermansia muciniphila Ameliorates Alcoholic Liver Disease in Experimental Mice by Regulating Serum Metabolism and Improving Gut Dysbiosis

Alcoholic liver disease (ALD) represents a significant global health concern, yet the available treatment options remain limited. Numerous studies have shown that gut microbiota is a critical target for the treatment of ALD. Additionally, there is increasing evidence that host metabolism also plays a crucial role in the development of ALD. Akkermansia muciniphila has been demonstrated to ameliorate experimental ALD through its modulatory effects on the intestinal vascular barrier, enhancement of mucus layer thickness, and promotion of intestinal tight junction proteins. Nevertheless, there is a dearth of studies investigating the impact of A. muciniphila on host metabolism and gut microbiota. Here, C57BL/6 mice were utilized to establish a modified NIAAA model in order to investigate the impact of the oral administration of A. muciniphila during the development of ALD. Furthermore, we employed targeted metabolomics to analyze the serum metabolomic profiles of the mice and 2bRAD-M sequencing to comprehensively examine the underlying mechanisms of the efficacy of A. muciniphila on ALD. Our results illustrated that the oral administration of A. muciniphila alleviated alcohol-induced liver injury in conjunction with encouraged serum levels of ornithine and diminished the elevation of oxalic acid levels induced by alcohol intake. In addition, A. muciniphila also inhibited the proliferation of harmful bacteria, such as Escherichia coli and Helicobacter hepaticus, induced by alcohol consumption while promoting the growth of butyrate-producing and commensal bacteria, including Paramuribaculum intestinale and Bacteroides ovatus. In conclusion, this study suggests that A. muciniphila restores ALD by regulating the gut microbiota, and this corrective effect is associated with alterations in the serum metabolism. Our research supplies a theoretical basis for developing A. muciniphila as an innovative generation of probiotic for preventing and managing ALD.

Helicobacter hepaticus promotes liver fibrosis through oxidative stress induced by hydrogenase in BALB/c mice

BACKGROUND

It has been documented that Helicobacter hepaticus produces a nickel-containing hydrogen-oxidizing hydrogenase enzyme, which is necessary for hydrogen-supported amino acid uptake. Although H. hepaticus infection has been shown to promote liver inflammation and fibrosis in BALB/c mice, the impact of hydrogenase on the progression of liver fibrosis induced by H. hepaticus has not been explored.

MATERIALS AND METHODS

BALB/c mice were inoculated with hydrogenase mutant (ΔHyaB) or wild type (WT) H. hepaticus 3B1 for 12 and 24 weeks. H. hepaticus colonization, hepatic histopathology, serum biochemistry, expression of inflammatory cytokines, and oxidative stress signaling pathways were detected.

RESULTS

We found that ΔHyaB had no influence on the colonization of H. hepaticus in the liver of mice at 12 and 24 weeks post infection (WPI). However, mice infected by ΔHyaB strains developed significantly alleviated liver inflammation and fibrosis compared with WT infection. Moreover, ΔHyaB infection remarkably increased the expression of hepatic GSH, SOD, and GSH-Px, and decreased the liver levels of MDA, ALT, and AST compared to WT H. hepaticus infected group from 12 to 24 WPI. Furthermore, mRNA levels of Il-6, Tnf-α, iNos, Hmox-1, and α-SMA were significantly decreased with an increase of Nfe2l2 in the liver of mice infected by ΔHyaB strains. In addition, ΔHyaB H. hepaticus restored the activation of the Nrf2/HO-1 signaling pathway, which is inhibited by H. hepaticus infection.

CONCLUSIONS

These data demonstrated that H. hepaticus hydrogenase promoted liver inflammation and fibrosis development mediated by oxidative stress in male BALB/c mice.

The alleviating effect of ellagic acid on DSS-induced colitis via regulating gut microbiomes and gene expression of colonic epithelial cells

The anti-inflammatory effect of ellagic acid (EA) and its possible underlying mechanism in dextran sulfate sodium (DSS)-induced mouse chronic colonic inflammation were studied. It was observed that EA administration significantly alleviated the colonic inflammation phenotypes, including decreasing the disease activity index (DAI), enhancing the body weight loss, and improving the shortened length of the colon and pathological damage of colon tissue. Additionally, EA reshaped the constitution of the gut microbiota by elevating the ratio of Bacteroidetes along with Bacteroides and Muribaculaceae, while decreasing the proportion of Firmicutes. The Phylogenetic Investigation of Communities by Reconstruction of Unobserved States 2 (PICRUSt2) revealed that the metabolic function of the gut microbiota was also changed. Furthermore, mouse colon transcriptome analysis showed that the tight junction and peroxisome proliferator-activated receptor (PPAR) signaling pathways were activated and the expressions of related genes were upregulated after EA intervention. These results showed that EA could remodel the gut bacterial composition, change the intestinal epithelial cell gene expressions in mice, and consequently improve the colonic inflammatory symptoms.

The deubiquitinase OTUD4 inhibits the expression of antimicrobial peptides in Paneth cells to support intestinal inflammation and bacterial infection

Dysfunction of the intestinal epithelial barrier causes microbial invasion that would lead to inflammation in the gut. Antimicrobial peptides (AMPs) are essential components of the intestinal epithelial barrier, while the regulatory mechanisms of AMPs expression are not fully characterized. Here, we report that the ovarian tumor family deubiquitinase 4 (OTUD4) in Paneth cells restricts the expression of AMPs and thereby promotes experimental colitis and bacterial infection. OTUD4 is upregulated in the inflamed mucosa of ulcerative colitis patients and in the colon of mice treated with dextran sulfate sodium salt (DSS). Knockout of OTUD4 promotes the expression of AMPs in intestinal organoids after stimulation with lipopolysaccharide (LPS) or peptidoglycan (PGN) and in the intestinal epithelial cells (IECs) of mice after DSS treatment or Salmonella typhimurium (S.t.) infection. Consistently, Vil-Cre;Otud4fl/fl mice and Def-Cre;Otud4fl/fl mice exhibit hyper-resistance to DSS-induced colitis and S.t. infection compared to Otud4fl/fl mice. Mechanistically, knockout of OTUD4 results in hyper K63-linked ubiquitination of MyD88 and increases the activation of NF-κB and MAPKs to promote the expression of AMPs. These findings collectively highlight an indispensable role of OTUD4 in Paneth cells to modulate AMPs production and indicate OTUD4 as a potential target for gastrointestinal inflammation and bacterial infection.

Disability and the (dysbiotic) gut: Sensing, tasting and knowing with food

This article offers insights into eating practices, conceptualising and making of 'good' food by people living with chronic disease. Based on ethnographic research focussing on people with Inflammatory Bowel Disease (Crohn's disease, ulcerative colitis and undefined IBD) in the Czech Republic, we explore what it would mean to conceptualise disability from the non-normative gut. We trace the practices of tinkering with foods and one's body, and ways of learning to sense (with) dysbiotic guts that people with IBD develop. Departing from the established notions of digestion and metabolism as universal biological processes, people with IBD create an embodied crip archive of knowledge through their eating practices, ways of making and sensing food and metabolic sampling. Most importantly, these practices offer, as we argue, new pathways into exploring crip embodiments as a place from which to acknowledge and do more-than-human collaboration, heath and ecologies.

Targeting pathophysiological changes using biomaterials-based drug delivery systems: A key to managing inflammatory bowel disease

Inflammatory bowel disease (IBD) is a gastrointestinal disorder, affecting about several million people worldwide. Current treatments fail to adequately control some clinical symptoms in IBD patients, which can adversely impact the patient's quality of life. Hence, the development of new treatments for IBD is needed. Due to their unique properties such as biocompatibility and sustained release of a drug, biomaterials-based drug delivery systems can be regarded as promising candidates for IBD treatment. It is noteworthy that considering the pathophysiological changes occurred in the gastrointestinal tract of IBD patients, especially changes in pH, surface charge, the concentration of reactive oxygen species, and the expression of some biomolecules at the inflamed colon, can help in the rational design of biomaterials-based drug delivery systems for efficient management of IBD. Here, we discuss about targeting these pathophysiological changes using biomaterials-based drug delivery systems, which can provide important clues to establish a strategic roadmap for future studies.