Dextran Sulfate Sodium Research Articles

The gut microbiota is essential for Trichinella spiralis-Evoked suppression of colitis.

Inflammatory bowel disease (IBD) increases the risk of colorectal cancer, and it has the potential to diminish the quality of life. Clinical and experimental evidence demonstrate protective aspects of parasitic helminth infection against IBD. However, studies on the inhibition of inflammation by helminth infection have overlooked a key determinant of health: the gut microbiota. Although infection with helminths induces alterations in the host microbiota composition, the potential influence and mechanism of helminth infections induced changes in the gut microbiota on the development of IBD has not yet been elucidated. In this study, we analyzed the intersection of helminth Trichinella spiralis and gut bacteria in the regulation of colitis and related mechanisms. T. spiralis infected mice were treated with antibiotics or cohoused with wild type mice, then challenged with dextran sodium sulfate (DSS)-colitis and disease severity, immune responses and goblet cells assessed. Gut bacteria composition was assessed by 16S rRNA sequencing and short-chain fatty acids (SCFAs) were measured. We found that protection against disease by infection with T. spiralis was abrogated by antibiotic treatment, and cohousing with T. spiralis- infected mice suppressed DSS-colitis in wild type mice. Bacterial community profiling revealed an increase in the abundance of the bacterial genus Muribaculum and unclassified_Muribaculaceae in mice with T. spiralis infection or mice cohoused with T. spiralis- infected mice. Metabolomic analysis demonstrated significantly increased propionic acid in feces from T. spiralis- infected mice. Data also showed that the gut microbiome modulated by T. spiralis exhibited enhanced goblet cell differentiation and elevated IL-10 levels in mice. These findings identify the gut microbiome as a critical component of the anti- colitic effect of T. spiralis and gives beneficial insights into the processes by which helminth alleviates colitis.

Cyclomodulins-harboring Escherichia coli isolated from obese and normal-weight subjects induces intestinal dysplasia in a mouse model.

Recently, cyclomodulins have been identified in Escherichia coli (E. coli), which can induce dysplastic damage. This work aimed to determine the dysplastic activity of cyclomodulin-harboring E. coli isolated from CRC patients, obese and normal-weight subjects in a mouse model. Forty-two mice were pretreated with streptomycin, azoxymethane, and dextran sodium sulfate. Mice were infected with E. coli pks + isolated from a CRC patient, with E. coli pks + cif + isolated from obese or normal-weight subjects, or with E. coli HB101. The presence of cyclomodulin-harboring E. coli in the feces, weight loss, changes in fecal consistency, and the presence of blood in the feces were monitored and used to assess the disease activity index (DAI). After 62 days, the mice were sacrificed to evaluate the presence of intestinal polyps and dysplastic damage by histologic sections. Cyclomodulin-harboring E. coli colonized the mice; these mice exhibited weight loss and watery diarrhea, and isolated normal-weight E. coli had a higher DAI. Polyps were observed in mice infected with cyclomodulin-harboring E. coli in the ileum but to a greater extent in obese isolates. E. coli isolated from CRC showed more significant endothelial damage associated with dysplasia in the ileum in equal proportions from obese and normal-weight isolates. In conclusion, E. coli harboring cyclomodulins isolated from CRC, obesity, or normal weight can cause dysplastic damage in the ileum of mice and may be a risk factor for CRC development.

Effects of water-insoluble wheat bran-fraction powder on disease activity and caecal microbiota in dextran sodium sulphate-induced inflammatory bowel disease mouse model.

Water-soluble arabinoxylan exerts anti-colitic effect and exhibits ameliorative activity in an inflammatory bowel disease (IBD) mouse model. Water soluble fibre from wheat bran (WB) also exhibits anti-colitic effect. However, arabinoxylan is a primary compound of insoluble polysaccharide (hemicellulose) in WB. This study aimed to clarify the anti-IBD effects of the WB water-soluble (WBS) and water-insoluble (WBI) fractions. WB suspension was autoclaved and fractionated to WBS and WBI. C57BL/6 mice were divided into control (CT), dextran sodium sulphate (DSS), WBI, and WBS groups. They were fed as follows from day 1: CT, standard diet and distilled water; DSS and WBI, 3% (w/v) DSS in drinking water; WBI, 8% (w/w) WBI diet; and WBS, 50% (v/v) WBS and 3% (w/v) DSS in water. DSS group mice showed diarrhoea, body weight reduction, and blood in faeces by day 5 and colon tissue damage by day 6. These inflammatory indices were significantly inhibited by treatment with WBI. Amplicon sequencing of the 16S rDNA (V4) gene of the caecal contents of the CT, DSS, and WBI groups showed that the abundances of Escherichia, Allobaculum, and Bacteroidaceae increased and that of Faecalibaculum decreased in the DSS group. KEGG pathway prediction showed that amino acid metabolism and lipopolysaccharide biosynthesis decreased and increased, respectively, in the DSS group. However, WBI treatment tended to suppress these effects. WBI, rather than WBS, reduces inflammation and maintains the gut microbiota. However, further studies are warranted to elucidate the properties of the WBI active components and efficacy of WBI metabolites on gut microbiota, particularly on Faecalibaculum.

Leucine-Enriched Diet Reduces Fecal MPO but Does Not Protect Against DSS Colitis in a Mouse Model of Crohn’s Disease-like Ileitis

Understanding the complex link between inflammation, gut health, and dietary amino acids is becoming increasingly important in the pathophysiology of inflammatory bowel disease (IBD). This study tested the hypothesis that a leucine-rich diet could attenuate inflammation and improve gut health in a mouse model of IBD. Specifically, we investigated the effects of a leucine-rich diet on dextran sulfate sodium (DSS)-induced colitis in germ-free (GF) SAMP1/YitFC (SAMP) mice colonized with human gut microbiota (hGF-SAMP). hGF-SAMP mice were fed one of four different diets: standard mouse diet (CHOW), American diet (AD), leucine-rich AD (AD + AA), or leucine-rich CHOW diet (CH + AA). Body weight, myeloperoxidase (MPO) activity, gut permeability, colonoscopy scores, and histological analysis were measured. Mice on a leucine-rich CHOW diet showed a decrease in fecal MPO prior to DSS treatment as compared to those on a regular diet (p > 0.05); however, after week five, prior to DSS, this effect had diminished. Following DSS treatment, there was no significant difference in gut permeability, fecal MPO activity, or body weight changes between the leucine-supplemented and control groups. These findings suggest that while a leucine-rich diet may transiently affect fecal MPO levels in hGF-SAMP mice, it does not confer protection against DSS-induced colitis symptoms or mitigate inflammation in the long term.

Diallyl trisulfide alleviates dextran sulphate sodium-induced colitis in mice by inhibiting NLRP3 inflammasome activation via ROS/Trx-1 pathway.

Diallyl trisulfide (DATS), a sulphur-containing compound isolated from the medicinal food plant garlic, has been previously reported to attenuate experimental colitis induced by either dextran sodium sulphate (DSS) or 2,4,6-trinitrobenzenesulfonic acid (TNBS) in mice; however, the underlying mechanism remains to be identified. In this study, we deciphered the key mechanism by which DATS alleviates ulcerative colitis (UC). We showed that oral administration of DATS for 10 consecutive days greatly restrained the infiltration of macrophages and the pathological changes in colonic tissues of mice with DSS-induced colitis. DATS treatment notably dampened the content of IL-1β and IL-18 and suppressed NLRP3 inflammasome activation in colon. Mechanistically, DATS effectively diminished the generation of ROS in macrophages. The suppressive effect of DATS on the activation of NLRP3 inflammasome and downregulation of IL-18 and IL-1β levels was blunted by xanthine oxidase. Further studies revealed that DATS inhibited NF-κB pathway activation by suppressing the expression of Trx-1, thereby inhibiting NLRP3 inflammasome activation. Trx-1 overexpression and interference in macrophages promoted and diminished NLRP3 inflammasome activation, respectively. In summary, garlic and its main active ingredient DATS have potentials to prevent and treat UC, and DATS functions by inhibiting NLRP3 inflammasome activation via Trx-1/ROS pathway.

Unveiling the therapeutic potential and mechanism of inulin in DSS-induced colitis mice

Inulin has been reported to alleviate colitis. In this study, colitis patients' feces were used to simulate fermentation to demonstrate changes in the microbiota profile in the presence of inulin. We found inulin can reshape the gut microbiota profile of colitis patients, especially by altering the abundance of Faecalibacterium and Blautia. Interestingly, the subsequent co-culture with inulin demonstrated that inulin promoted the growth of these two strains of bacteria. The dextran sodium sulfate (DSS)-induced mouse model was used to examine the effect of inulin and its combination with two probiotics on colitis. Results showed that all three treatments can alleviate the clinical symptoms, including weight-losing, colon-shortening, and the Disease Activity Index (DAI) score. Further investigations showed that the administrations regulate colitis mice's pro- and anti-inflammatory cytokines, such as TNF-α, IL-1β, IL-6, IL-10, and IL-17. Also, they alter the relative abundance of Faecalibacterium and Blautia, change the short-chain fatty acids (SCFAs) profile in the cecum and colon, and improve the intestinal barrier; specifically, the intervention increased the expressions of Claudin, Occludin, Zonula Occludens (ZO)-1, and Mucin (MUC)-2 in colonic tissues, thus restoring the colonic tissue structure and morphology of colitis mice. Collectively, our results confirm that inulin can alter the colitis patients' characteristic microbial community, and they can ameliorate experimental colitis by inhibiting the TRL4/MyD88/NF-κB signaling pathway—improving the inflammatory response and enhancing the intestinal barrier. In conclusion, we propose that inulin may hold promise as a functional food therapeutic approach for the treatment of colitis.

Glycyrrhizic acid and patchouli alcohol in Huoxiang Zhengqi attenuate intestinal inflammation and barrier injury via regulating endogenous corticosterone metabolism mediated by 11β-HSD1.

Ulcerative colitis (UC), a chronic inflammatory bowel disease, has become a significant public health challenge due to the limited effectiveness of available therapies. Huoxiang Zhengqi (HXZQ), a well-established traditional Chinese formula, shows potential in managing UC, as suggested by clinical and pharmacological studies. However, the active components and mechanisms responsible for its effects remain unclear. This study aimed to identify the bioactive components of HXZQ responsible for its therapeutic effects on UC and to elucidate their underlying mechanisms. The effect of HXZQ against dextran sodium sulfate (DSS) -induced colitis was investigated. Ingredients in HXZQ were characterized and analyzed in colitic mice using liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS). In vitro, biological activity of compounds was assessed using lipopolysaccharide (LPS)-induced Ana-1 cells and bone marrow-derived macrophages (BMDMs), tumor necrosis factor-alpha-induced Caco-2 cells, and isolated intestinal crypts from colitic mice. These results were confirmed in vivo. The targets of the components were identified through bioinformatics analysis and validated via molecular docking, enzyme inhibition assays, and in vivo experiments. Hematoxylin and eosin (HE) staining, periodic acid-Schiff (PAS) staining, immunohistochemistry, enzyme-linked immunosorbent assay (ELISA), western blotting, and quantitative real-time polymerase chain reaction (qPCR) were employed to confirm the pharmaceutical effects. A clinical equivalent dose of HXZQ (2.5 mL/kg) effectively treated DSS-induced colitis. 113 compounds were identified in HXZQ, with 35 compounds detected in colitic mice. Glycyrrhizic acid (GA) and patchouli alcohol (PA) emerged as key contributors to the anti-colitic effects of HXZQ. Further investigation revealed that HXZQ and its active components decreased the levels of pro-inflammatory cytokines TNF-α, interleukin-1β (IL-1β), and interleukin-6 (IL-6) in colon, likely by inhibiting nuclear factor kappa-B (NF-κB) signaling pathway. This inhibition indirectly activated the intestinal farnesoid X receptor (FXR) signaling pathway, correcting bile acid imbalances caused by colitis. Additionally, these components significantly enhanced the expression of tight junction proteins ZO-1 and Occludin, as well as the adhesion protein E-cadherin, and reduced goblet cell loss, thereby repairing intestinal barrier injury. Mechanistically, GA and PA were found to inhibit 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) activity, leading to increased local active corticosterone levels in the intestine to exert anti-inflammatory effects. Notably, the inhibition of 11β-HSD1 with the selective inhibitor BVT ameliorated colitis in mice. HXZQ exhibits therapeutic effects on UC, primarily through GA and PA inhibiting 11β-HSD1. This suggests new natural therapy approaches for UC and positions 11β-HSD1 as a potential target for colitis treatment.

The combination of FLCWK with 5-FU inhibits colon cancer and multidrug resistance by activating PXR to suppress the IL-6/STAT3 pathway.

5-fluorouracil (5-FU) is a preferred chemotherapeutic agent for the treatment of colon cancer. Nonetheless, its clinical effectiveness is frequently hampered by suboptimal therapeutic outcomes and the emergence of drug resistance. Therefore, there exists a pressing demand for novel therapeutic agents to circumvent chemoresistance. The pregnane X receptor (PXR) exerts a pivotal regulatory influence on the proliferation, invasion, and chemoresistance mechanisms in colon cancer. Activation of PXR drives up the transcription of the multidrug resistance gene (MDR1), thus prompting the expression of P-glycoprotein (P-gp) responsible for conferring tumour resistance. This study scrutinized the potential of Fengliao Changweikang (FLCWK) in augmenting the efficacy of 5-FU in the management of colon cancer. To this end, we engineered colon cancer cells with varied levels of PXR expression via lentiviral transfection, subsequently validating the findings in nude mice. By means of MTT assays, flow cytometry apoptosis analysis, Western blotting and immunofluorescence, we probed into the prospective impacts of FLCWK and 5-FU on cellular viability and resistance. Our results revealed that while upregulation of PXR amplified the therapeutic benefits in colon cancer treatment, it concurrently heightened resistance levels. FLCWK demonstrated a capacity to reduce P-gp expression, with the combined administration of FLCWK and 5-FU effectively reversing resistance mechanisms. Furthermore, activation of PXR was found to impede the IL-6/STAT3 signalling pathway. In an effort to mimic the development of colon cancer, we established an azomethane oxide (AOM)/ dextran sodium sulfate (DSS) mouse model, showing that FLCWK bolstered the inhibitory effects of 5-FU, impeding the progression of colon cancer. In summation, our findings point towards the potential of FLCWK in the treatment of colon cancer, particularly in strengthening the therapeutic efficacy of 5-FU in the prevention and control of the disease.

The MicroRNA miR-223 Constrains Colitis-associated Tumorigenesis by Limiting Myeloid Cell Infiltration and Chemokine Expression.

Aberrant intestinal inflammation plays a critical role in the development of colitis-associated colorectal cancer (CAC), yet the mechanisms controlling tumor development by the myeloid immune compartment are not fully understood. Although altered microRNA expression is observed in CAC, it is also unclear how myeloid-specific microRNAs impact the inflammatory process that underpins the continuum from ulcerative colitis to tumorigenesis. In this study, we report that miR-223 acts to limit myeloid-driven inflammation in the azoxymethane (AOM)-dextran sodium sulfate (DSS) model of CAC in mice. In this model, miR-223-/y mice present with significantly larger tumors with an enhanced proliferative signature. Immunoprofiling showed that miR-223-/y mice have significantly increased colonic myeloid immune infiltrate (neutrophils, monocytes, and macrophages) following AOM-DSS. This was accompanied by an increased inflammatory chemokine and cytokine signature for monocytes and neutrophils. Bone marrow chimera studies demonstrate that myeloid-expressed miR-223 is responsible for the enhanced tumor proliferation and inflammatory response. RNA sequencing identified several pathways that could be contributing to the development of CAC in miR-223-/y mice, including the IL-6/IL-17a cytokine family and STAT3 signaling. Lastly, neutrophil depletion with an anti-GR1 Ab (Ly6G/Ly6C) during the initial phase of the AOM-DSS model reduced the tumor burden in miR-223-/y mice. Collectively, our data indicate that miR-223 is an important regulator of mucosal inflammation and acts to constrain the progression from ulcerative colitis to CAC by limiting myeloid-associated inflammation.

Metabolomic insights into the beneficial effects of dietary purple potato on DSS-induced murine colon colitis

Inflammatory bowel disease (IBD) is characterized by disturbance in intestinal flora and metabolomic profiles. Building on previous findings that purple potato (PP) supplementation suppresses inflammation and restores intestinal barrier in dextran sulfate sodium (DSS)-treated mice, this study examined changes in the fecal metabolome in the same cohort. Mice were fed 0 % or 10 % PP for 7 weeks, with DSS administered in the fifth week of dietary treatment followed by one-week normal drinking water recovery. A total of 68 metabolites, including amino acids, fatty acids, organic acids, carbohydrates, and polyamines, were significantly altered across the groups. PP supplementation reversed changes in 13 of the 25 DSS-altered metabolites. Six microbial metabolites derived from PP polyphenols were identified and positively correlated with M2 macrophage polarization. Data suggest that dietary PP is effective in reducing inflammation and improves gut metabolites in DSS-induced colitis mice, offering a potential dietary therapy for managing IBD.

Tarm1 may affect colitis by regulating macrophage M1 polarization in a mouse colitis model.

In this study, we aimed to explore the role of Tarm1 in juvenile mice with dextran sulfate sodium (DSS)-induced colitis and elucidate the mechanisms that affect intestinal barrier function. A DSS-induced pediatric inflammatory bowel disease mouse model was established using 4-week-old juvenile mice. Disease activity index and histopathological damage scores were determined using hematoxylin and eosin (H&E) staining. Tarm1, F4/80, CD68, and CD86 levels were detected using qPCR, western blotting, and immunofluorescence. Trans epithelial electric resistance (TEER) was detected using the transwell assay. Results revealed that juvenile colitis mice fed 4% DSS drinking water had increased Tarm1 expression in the colon tissue, increased macrophage M1 polarization, higher expression of pro-inflammatory cytokines, and an impaired intestinal mucosal barrier, compared with the control group. Tarm1-knockdown RAW264.7 cells inhibited lipopolysaccharide (LPS)-induced M1 polarization and attenuated barrier damage in co-cultured intestinal epithelial cells. Tarm1 expression was increased in colonic tissues of juvenile mice with colitis, and LPS-induced M1 polarization and intestinal barrier damage were attenuated in Tarm1-knockdown RAW264.7 cells. This suggests that attenuation of Tarm1 expression is a potential target for pediatric inflammatory bowel disease therapy.

Metabolomics reveals the potential metabolic mechanism of infliximab against DSS-induced acute and chronic ulcerative colitis.

Inflammatory bowel disease (IBD) is often accompanied by metabolic imbalance, and infliximab (IFX) can alleviate IBD symptoms, but its metabolic mechanisms remain unclear. To investigate the relationship between IBD, metabolism, and IFX, an acute and chronic ulcerative colitis (UC) model induced by dextran sulfate sodium (DSS) was established. Plasma samples were analyzed using ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry, followed by multivariate statistical analysis. The results showed that IFX could alleviate colonic shortening and reduce colonic pathological damage in acute and chronic mouse colitis, improve acute and chronic UC, and ameliorate metabolic disturbances. Among the 104 elevated metabolites and 170 decreased metabolites, these metabolites mainly belonged to amino acids, glucose, and purines. The changes in these metabolites were mainly associated with drug metabolism-other enzymes, riboflavin metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, phosphonate and phosphinate metabolism, and phenylalanine metabolism. In summary, this study provides a valuable approach to explore the metabolic mechanisms of IFX in treating acute and chronic UC from a metabolomics perspective.

Lactobacillus rhamnosus 1.0320 Postbiotics Ameliorate Dextran Sodium Sulfate-Induced Colonic Inflammation and Oxidative Stress by Regulating the Intestinal Barrier and Gut Microbiota.

Probiotics are increasingly being used as an adjunctive therapy for ulcerative colitis. However, some safety issues have been found in the clinical use of probiotics. Postbiotics have attracted much attention due to their storage stability, safety, and potential functions, but the dose required to exert a significant protective effect is unknown. Therefore, this study evaluated the potential mechanisms of different doses (200, 400, 600 mg/kg) of Lactobacillus rhamnosus 1.0320 postbiotics (1.0320P) in alleviating dextran sodium sulfate (DSS)-induced colitis. The study revealed that 1.0320P could mitigate DSS-induced colitis with signs of reductions in the disease activity index, amelioration of colon tissue damage, decreased secretion of proinflammatory cytokines, reduced oxidative stress levels, and lower bone marrow peroxidase activity. Furthermore, high dose of 1.0320P could upregulated the expression of key proteins in the Nrf2/ARE pathway (NQO1, Nrf2, and HO-1) and downregulated the expression of key proteins in the TLR4/NF-κB signaling pathway (TLR4, MyD88, and NF-κB p65). In addition, high dose of 1.0320P could upregulate the expression of tight junction (TJ) proteins including ZO-1, Occludin, and Claudin-1, contributing to the restoration of the intestinal mucosal barrier function. Additionally, 1.0320P was found to effectively correct imbalances in the intestinal microbiota and enhance the synthesis of short-chain fatty acids (SCFAs), thereby regulating homeostasis in the intestinal internal environment. Overall, our findings suggest that postbiotics could ameliorate colonic inflammation while being somewhat dose-dependent. This study provides new insights into postbiotics as a next-generation biotherapeutic agent for the treatment of ulcerative colitis and even other diseases.

Probiotic and Rice-Derived Compound Combination Mitigates Colitis Severity

Background: This study investigated the ability of Enterococcus lactis (E. lactis) and Hasawi rice protein lysate (HPL) to suppress colitis induced by dextran sulfate sodium (DSS) in miceColitis is characterized by inflammation of the colon, and exploring potential therapeutic agents could lead to improved management strategies. Methods: Male mice were subjected to DSS treatment to induce colitis, followed by supplementation with E. lactis and/or HPL. The study assessed various parameters, including disease activity index (DAI) scores, gut permeability measured using FITC-dextran, and superoxide dismutase (SOD) activity in excised colon tissues from both treated and untreated control groups. Results: E. lactis supplementation significantly alleviated DSS-induced colitis, as evidenced by improved DAI scores and enhanced gut permeability. Notably, E. lactis combined with HPL (0.1 mg/108) exhibited superior tolerance to a 0.5% pancreatin solution compared to E. lactis alone. Both E. lactis and the combination treatment significantly increased SOD activity (5.6 ± 0.23 SOD U/mg protein for E. lactis and 6.7 ± 0.23 SOD U/mg protein for the combination) relative to the Azoxymethane (AOM)/DSS group, suggesting a reduction in oxidative stress. Additionally, pro-inflammatory markers were significantly reduced in the group receiving both E. lactis and HPL compared to the E. lactis-only group. Levels of proteins associated with cell death, such as PCNA, PTEN, VEGF, COX-2, and STAT-3, were significantly decreased by 14.8% to 80% following E. lactis supplementation, with the combination treatment showing the most pronounced effects. Conclusions: These findings suggest E. lactis supplementation may be beneficial for colitis, with HPL potential to enhance its effectiveness.

Osa-miR168a, a Plant miRNA That Survives the Process of In Vivo Food Digestion, Attenuates Dextran Sulfate Sodium-Induced Colitis in Mice by Oral Administration.

Previous studies showed that osa-miR168a, a plant miRNA rich in fruits and vegetables, had cross-kingdom biological effects on immunocytes, silkworms, and rodents. In this study, the effects of miR168a on mouse colitis induced by dextran sulfate sodium (DSS) were investigated. The results showed that miR168a oligomers were resistant during the process of food digestion, ending up with a residual concentration of 67.8 ± 11.2 fM in mouse intestines 4 h after oral gavage. More importantly, direct oral administration of the miRNA to the colitis mice significantly ameliorated the progression of the disease, as evidenced by the reduction in DAI score, histopathological lesions, and proinflammatory cytokines. Repairing intestinal barrier function by promoting the regeneration of TJ proteins and the mucus layer, suppressing oxidative stress and colonic inflammation via modulating Nrf2 and NF-κB signaling pathways, and restoring the imbalanced gut microbiota caused by DSS are proposed mechanisms behind the anticolitis activity of miR168a. This study provided new evidence of the cross-kingdom regulatory effects of dietary miRNAs, suggesting the potential of the plant miRNA for the prevention and treatment of inflammatory bowel diseases.

Anti-inflammatory effects of para-quinone methide derivatives on ulcerative colitis

A series of para-quinone methide derivatives were evaluated their anti-inflammatory activity. Through the screening of the lipopolysaccharide (LPS)-induced inflammatory cell model in Raw264.7 cells, it was found that the inhibitory activity of meta-substituted derivatives on NO production was superior to that of ortho- and para-substituted derivatives. Among them, in the inflammatory cell model, the meta-trifluoromethyl substituted para-quinone methide derivative 1i had the best activity in inhibiting LPS-induced excess generation of NO. And 1i could effectively inhibit the increase of ROS in inflammatory cells, the expression of iNOS related to the production of NO, and the expressions of inflammation related initiating protein TLR4, pro-inflammatory cytokines IL-6 and TNF-α, inflammasome NLRP3 and Caspase1. In the dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mouse model, the active derivative 1i could inhibit DSS-induced colon shortening, and reverse DSS-induced pathological changes in colon tissue, such as inflammatory infiltration, structural destruction and crypt disappearance. 1i could effectively inhibit oxidative stress, inflammation and apoptosis in UC mice. Moreover, through the determination of serum biochemical indicators, tissue pathologies and tissue organ indexes, 1i could effectively reverse the damage to mouse liver and kidney caused by DSS, playing a protective role in liver and kidney of mice. In summary, 1i was an effective anti-inflammatory reagent and could be developed as a potential drug for anti-UC.

The Therapeutic Effects of Lactic Acid Bacteria Isolated from Spotted Hyena on Dextran Sulfate Sodium-Induced Ulcerative Colitis in Mice

Background: Inflammatory bowel disease (IBD) is a chronic condition characterized by recurrent episodes and an unclear etiology. Given the limitations of current therapeutic options, which include suboptimal efficacy and significant side effects, there is a pressing need to explore novel treatments. Probiotics derived from diverse species have been identified as a promising approach for managing IBD, owing to their anti-inflammatory properties and their ability to regulate gut flora, among other beneficial effects. Methods: In this study, three strains of lactic acid bacteria (LAB) were isolated from the feces of the scavenger spotted hyena (Crocuta crocuta), a scavenging mammal. Based on their capability to survive within and adhere to the gastrointestinal tract, along with their profile of antibiotic resistance, a high-quality strain of Lactobacillus acidophilus (LA) was selected and demonstrated to be safe for mice. Subsequently, the therapeutic efficacy of LA was evaluated using a dextran sulfate sodium (DSS)-induced model of ulcerative colitis in mice. Results: The results indicated that LA restored the disease activity index and improved histopathological lesions in the model group. It also reduced inflammation and oxidative stress and significantly restored the expression of mucins and intestinal tight junction (TJ) proteins (ZO-1, Occludin). Furthermore, LA corrected the DSS-induced disruption of the intestinal flora, leading to a significant decrease in the prevalence of potentially harmful bacterial genera, such as Bacteroides, and an increase in beneficial bacterial genera, including Lactobacillus. In conclusion, Lactobacillus acidophilus LA1, isolated from spotted hyena feces, has potential as a functional supplement for alleviating symptoms of IBD and regulating intestinal flora.

Potential of Fiber and Probiotics to Fight Against the Effects of PhIP + DSS-Induced Carcinogenic Process of the Large Intestine.

We determined the in vivo counteracting effect of fiber and probiotic supplementation on colonic mucosal damage and alterations in gut microbiota caused by 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP) and sodium dextran sulfate (DSS). Male Fischer-344 rats were randomly divided into 4 groups: control (standard diet), PhIP + DSS group (standard diet + PhIP + DSS), fiber (fiber diet + PhIP + DSS), and probiotic (probiotic diet + PhIP + DSS). The intake of PhIP + DSS for 3 weeks induced colonic mucosal erosion, crypt loss, and inflammation, and the distal colon was more severely damaged. Fiber alleviated colonic mucosal damage by reducing crypt loss and inflammation, while the probiotic increased colon length. The intake of PhIP + DSS increased the fecal relative abundance of Clostridia UCG014 along the intervention, in contrast to the lower abundances of these taxa found after PhIP + DSS administration in the rats supplemented with probiotics or fiber. Fiber supplementation mitigated the histological damage caused by PhIP + DSS shifting the gut microbiota toward a reduction of pro-inflammatory taxa.

Lactiplantibacillus plantarum NMGL2 exopolysaccharide ameliorates DSS-induced IBD in mice mainly by regulation of intestinal tight junction and NF-κB p65 protein expression

Treatment of inflammatory bowel disease (IBD), a common chronic intestinal disease, by exopolysaccharides (EPSs) produced by lactic acid bacteria has raised increasing concerns. Here, the EPS produced by Lactiplantibacillus plantarum NMGL2 was evaluated for its ameliorating effect on dextran sodium sulfate (DSS)-induced IBD in mice. Administration of the EPS was shown to decrease the body weight loss and the values of disease activity index (DAI) and alleviate the colon damage as evidenced by an improvement in colonic length shortening, a reduction in colonic coefficient, and a reduction in colonic mucosal architecture and inflammatory infiltration. Cytokine assay of the blood and colon tissue samples showed that the EPS could decrease the levels of pro-inflammatory TNF-α and IL-1β, and increase anti-inflammatory IL-10. Oxidative stress assay of the colon tissue showed that the nitric oxide (NO) and malondialdehyde (MDA) levels decreased significantly (p < 0.05), while superoxide dismutase (SOD) and glutathione (GSH) levels increased significantly (p < 0.05) after the EPS intervention. These results were further confirmed by the significantly (p < 0.05) down-regulated levels of NF-κB p65, p-IKKβ, and p-IκBα, and significantly (p < 0.05) enhanced expression of ZO-1 and occludin, as evaluated by Western-blot analysis of these proteins expressed in colonic tissue. The EPS produced by L. plantarum NMGL2 alleviated IBD by suppressing the NF-κB signaling pathway, suggesting its potential as a functional food agent in the prevention of IBD.

Motor, mood, and memory impairments persist during remission periods in chronic colitis and are influenced by neuroinflammation and sex.

Ulcerative colitis is a chronic pathology characterized by relapsing-remitting phases of intestinal inflammation. Additionally, some patients develop neuropsychiatric disorders, such as depression and anxiety, or cognitive deficits. We aimed to investigate whether the development of chronic colitis elicits memory, locomotion, and mood impairments. It further examined whether these impairments are influenced by the relapsing-remitting phases of the colitis or by sex. Here, we used a chronic colitis model in male and female rats, induced with sodium dextran sulfate, mirroring the phases of human ulcerative colitis. Our results revealed that the severity of colitis was slightly higher in males than females. Chronic colitis triggered motor and short-term memory deficits and induced anxiety- and depression-like behaviors that remained throughout the development of the disease. There are also sex differences under control or inflammatory conditions. Therefore, in both situations, females compared to males displayed: (i) slightly lower locomotion, (ii) increased anxiety-like behaviors, (iii) similar depression-like behaviors, and (iv) similar short-term memory deficit. Additionally, under control conditions, the mRNA levels of IL-1β, IL-6, and TNF-α were higher in the female hippocampus. In both sexes, when chronic colitis was established, the neuroinflammation was evidenced by increased mRNA levels of these three cytokines in the hippocampus and in the motor and prefrontal cortices. Interestingly, this neuroinflammation was slightly greater in males. In summary, we show that the development of chronic colitis caused persistent behavioral abnormalities, highlighting sex differences, and that could be a consequence, at least in part, of the increase in IL-1β, IL-6, and TNF-α in the brain.