Efficacy and safety of drugs for ulcerative colitis

Hydrogen Regulates Ulcerative Colitis by Affecting the Intestinal Redox Environment

The redox balance in the intestine plays an important role in maintaining intestinal homeostasis, and it is closely related to the intestinal mucosal barrier, intestinal inflammation, and the gut microbiota. Current research on the treatment of ulcerative colitis has focused on immune disorders, excessive inflammation, and oxidative stress. However, an imbalance in intestinal redox reaction plays a particularly critical role. Hydrogen is produced by some anaerobic bacteria via hydrogenases in the intestine. Increasing evidence suggests that hydrogen, as an inert gas, is crucial for immunity, inflammation, and oxidative stress and plays a protective role in ulcerative colitis. Hydrogen maintains the redox state balance in the intestine in ulcerative colitis and reduces damage to intestinal epithelial cells by exerting its selective antioxidant ability. Hydrogen also regulates the intestinal flora, reduces the harmful effects of bacteria on the intestinal epithelial barrier, promotes the restoration of normal anaerobic bacteria in the intestines, and ultimately improves the integrity of the intestinal epithelial barrier. The present review focuses on the therapeutic mechanisms of hydrogen-targeting ulcerative colitis.

Ethyl acetate extract of Terminalia chebula alleviates DSS-induced ulcerative colitis in C57BL/6 mice

Background: The Chinese pharmacopeia records Terminalia chebula as effective in treating prolonged diarrhea and dysentery, blood in the stool, and prolapse. Modern pharmacological research proves it has multiple pharmacological benefits, including antioxidant, anti-inflammatory, analgesic, hepatoprotective, neuroprotective, and other properties. Objectives: This study aims to clarify the role of Terminalia chebula's ethyl acetate extract (TCEA) on ulcerative colitis (UC) induced by dextran sodium sulfate (DSS) in mice, as well as explore the potential mechanism of action. Materials and methods: The variation of different extracts of T. chebula was detected using the HPLC technique, and the main components in TCEA were identified. DSS was used to establish a mouse model to mimic the physiological state of UC in humans; the alleviating effect of TCEA and positive control 5-ASA on UC mice were evaluated by gavage treatment. Disease progression was assessed by monitoring the mouse's weight change and disease activity index (DAI). The changes in colon tissue were estimated by measuring colon length, HE, and AB-PAS staining and detecting oxidative stress parameters. The results draw from Western blot and real-time PCR showed the TLR4/MyD88/NF-κB pathway may involve in the anti-inflammatory activity of TCEA. Furthermore, the gut flora sequencing technique was employed to monitor the differentiation of intestinal microbiota of mice induced by DSS and TCEA treatment. Results: TCEA significantly lowered DAI scores and inhibited the weight loss and colonic shortening induced by DSS. The colon histomorphology and oxidative stress levels were enhanced after TCEA treatment compared with DSS induced UC group. TCEA attenuated the inflammatory response by regulating TLR4/MyD88/NF-κB pathway activation. Intestinal flora sequencing showed that DSS and TCEA greatly impacted mice's composition and diversity of intestinal microorganisms. But TCEA increased the abundance of Bacteroidetes and decreased the abundance of Firmicutes and Proteobacteria compared with the DSS group, which contributed a lot to returning the intestinal flora to a balanced state. Conclusion: This study confirms the alleviating effect of TCEA on UC and provides new ideas for developing TCEA into a new drug to treat UC.

Aloin A prevents ulcerative colitis in mice by enhancing the intestinal barrier function via suppressing the Notch signaling pathway

BACKGROUND

Previous studies reported that Aloe vera ameliorated DSS-induced colitis and promoted mucus secretion. However, the effect of Aloin A (AA), a major compound of Aloe vera, on colitis and its exact mechanism remains uncovered.

METHODS

C57BL/6 mice were successively subjected to 3% DSS solution for 5 days and distilled water for 2 days. Concurrently, AA (25, 50 mg/kg) and 5-aminosalicylic (500 mg/kg) were administrated intragastrically from day 1 to day 7. Colitis was evaluated by disease active index (DAI), colon length, inflammation response, and intestinal barrier function. In vitro LS174T cells challenged with 50 ng/ml of lipopolysaccharides (LPS) were used to validate the modulatory action of AA on the Notch signaling pathway.

RESULTS

Our results showed that oral administration with AA prominently prevented DSS-induced colitis symptoms in terms of decreased DAI, prevention of colon shortening, and reduced pathological damage. AA mitigated the inflammatory response evidenced by the decreased proinflammatory cytokines (TNF-α, IL-1β, IL-6) and increased anti-inflammatory cytokine (IL-10). Besides, AA inhibited apoptosis and facilitated proliferation in colons. Moreover, AA treatment up-regulated the expression of tight junction (TJ) proteins (ZO-1, Occludin) and promoted the secretion of MUC2 to decrease colon permeability. Mechanistically, AA inhibited the Notch pathway to promote the secretion of MUC2, which was consistent with LPS-challenged LS174 cells.

CONCLUSION

These results suggested that AA could prevent colitis by enhancing the intestinal barrier function via suppressing the Notch signaling pathway. Thus, AA might be a prospective remedy for ulcerative colitis.

Sanhuang Xiexin decoction ameliorates DSS-induced colitis in mice by regulating intestinal inflammation, intestinal barrier, and intestinal flora

ETHNOPHARMACOLOGICAL RELEVANCE

Sanhuang Xiexin decoction (SXD) is a widely applicated traditional Chinese medicine (TCM) with a significant intestinal anti-inflammatory effect.

AIM OF THE STUDY

To evaluate the therapeutic effect and elucidate the possible underlying mechanisms of SXD on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice.

METHODS

To model UC, 3% DSS was added to the drinking water for 7 days. The UC mice were grouped and treated with three doses of SXD (1.3, 2.6, and 6 g/kg) orally for 7 days. Mice body weight and disease activity index (DAI) scores were recorded daily. After treatment with SXD, the colon was removed, and the colon length and histopathological changes were recorded. Blood cells were counted and colonic inflammatory cytokines and oxidative stress indicators were examined. The key proteins in TLR4-MyD88-NF-κB signaling and the colonic barrier were determined by Western blot analysis. The restorative effect of SXD on intestinal flora was determined.

RESULTS

Treatment with SXD reduced DAI scores, increased body weight, improved colon shortening, and decreased colonic damage. SXD decreased the numbers of white blood cells (WBCs), increased the numbers of red blood cells (RBCs), and inhibited the expression of inflammatory cytokines and oxidative stress indicators. In addition, SXD displayed an effective anti-inflammatory effect by inhibiting the expression levels of p-IκBα, TLR4, MyD88, and p65. Furthermore, SXD significantly restored the integrity of the colonic barrier and the abundance of beneficial flora.

CONCLUSIONS

SXD significantly reduced DSS-induced colon damage when the dose was higher than 1.3 g/kg, and the middle dose group (2.6 g/kg) indicated the best effect. SXD effectively ameliorated DSS-induced UC in mice, possibly by inhibiting oxidative stress, protecting the mucosal barrier, inhibiting the TLR4-MyD88-NF-κB signaling pathway, and regulating the intestinal flora.

The potential mechanism of huazhuojiedu decoction in the treatment of ulcerative colitis based on network pharmacology and experimental validation

Huazhuojiedu decoction (HZJDD), a traditional Chinese medicine prescription, has been clinically proven to be an effective treatment for ulcerative colitis (UC). However, the mechanism of HZJDD in the treatment of UC remains unclear. This study combined network pharmacology with experimental validation to explore the potential mechanism of HZJDD on UC. First, the relationship network diagrams between HZJDD and UC were established based on multiple databases. Then, the HZJDD-UC intersection genes target network was constructed and Gene Ontology-Biological processes (GO-BP) analysis was performed to discover the potential pharmacological mechanism. Finally, the results of GO-BP were verified in dextran sulfate sodium salt (DSS) induced UC rats. The network pharmacology results showed that 119 active components and 146 potential targets were screened for HZJDD, and six of the top 15 biological processes belonged to inflammatory response, cellular response to hypoxia, and cellular response to lipopolysaccharide (LPS). The GO-BP results indicated that the mechanism of HZJDD treatment of UC was related to inflammation, oxidative stress, and the regulation of LPS. Animal experiments showed that HZJDD could significantly reduce the disease activity index (DAI) score, improve colon length, and effectively repair the histomorphological and micromorphological changes in DSS-induced UC rats. Moreover, HZJDD reduced the expressions of CRP, TNF-α, IL-6, LPS, IL-1β, and IL-18; downregulated the activity of MDA; and upregulated the activities of CAT, GSH, and SOD in DSS-induced UC rats. Furthermore, HZJDD suppressed the expression of the NLRP3/caspase-1 signaling pathway at the gene and protein levels to inhibit pyroptosis. Network pharmacology and animal experiments showed that HZJDD exerted a therapeutic effect on DSS-induced UC rats by reducing inflammation, oxidative stress, and restraining the NLRP3/caspase-1 signaling pathway to inhibit pyroptosis.

Alpinia hainanensis Rhizome Extract Ameliorates Dextran Sulfate Sodium-Induced Ulcerative Colitis: Active Ingredient Investigation and Evaluation

Alpinia hainanensis is an important food spice and ethnic medicine in Southwest China. In this study, we found that the EtOAc-soluble fraction (AHE) of the A. hainanensis rhizome ethanol extract could ameliorate dextran sulfate sodium-induced ulcerative colitis (UC). To explore active constituents, five pairs of previously unreported enantiomers (1-5), together with nine known ones (6-14), were obtained. Structural characterization was achieved by comprehensive spectroscopic methods. Compounds 1 and 2 were new curcumin-butyrovanillone hybrids featuring a rare structural fragment of 2,3-dihyrofuran. The anti-inflammatory activities of isolates were evaluated, and the results indicated that compounds (-)-1, (-)-3, 6, 9, 11, and 12 significantly inhibited the nuclear factor-κB signaling pathway. These findings indicate the major active fraction of the A. hainanensis rhizome ethanol extract enriched with diarylheptanoids, flavonoids, phenolics, and their hybrid mixtures, which could be developed as a nutritional and dietary supplement for treating UC.

Molecular mechanisms of Huanglian jiedu decoction on ulcerative colitis based on network pharmacology and molecular docking

Huanglian jiedu decoction (HLJDD) is a heat-clearing and detoxifying agent composed of four kinds of Chinese herbal medicine. Previous studies have shown that HLJDD can improve the inflammatory response of ulcerative colitis (UC) and maintain intestinal barrier function. However, its molecular mechanism is not completely clear. In this study, we verified the bioactive components (BCI) and potential targets of HLJDD in the treatment of UC using network pharmacology and molecular docking, and constructed the pharmacological network and PPI network. Then the core genes were enriched by GO and KEGG. Finally, the bioactive components were docked with the key targets to verify the binding ability between them. A total of 54 active components related to UC were identified. Ten genes are very important to the PPI network. Functional analysis showed that these target genes were mainly involved in the regulation of cell response to different stimuli, IL-17 signal pathway and TNF signal pathway. The results of molecular docking showed that the active components of HLJDD had a good binding ability with the Hub gene. This study systematically elucidates the “multi-component, multi-target, multi-pathway” mechanism of anti-UC with HLJDD for the first time, suggesting that HLJDD or its active components may be candidate drugs for the treatment of ulcerative colitis.

Protective effect of naringin ameliorates TNBS-induced colitis in rats via improving antioxidant status and pro-inflammatory cytokines

Aim: Ulcerative colitis (UC) is a chronic inflammatory bowel disease that disturbs the colon mucosal lining and is characterized by oxido-nitrosative stress and the release of pro-inflammatory cytokines. Naringin (NG) belongs to a group of chemicals called bioflavonoids derived from grapefruit and related citrus species. NG has been widely used as folk medicine in many countries, due to its several health benefits.Method: This study examined the effect of NG on 2,4,6 trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. Forty-two male Wistar rats were divided into seven groups like Normal Control (NC), Ethanol Control (EC), Disease Control (DC), NG 20 (20 mg/kg, p.o.), NG 40 (40 mg/kg, p.o.), NG 80 (80 mg/kg, p.o.), and Dexamethasone (DEX) (2 mg/kg, p.o.). Colitis was induced in Wistar albino rats by administering TNBS intra-rectally (in 50% ethanol). The rats were then given 14 days of NG (20, 40, and 80 mg/kg) and DEX (2 mg/kg) treatment. Several behavioral, biochemical, molecular, and histological analyses were performed.Result: The treatment of rats with NG significantly increased the body weight (p < .05, p < .01), hematological parameters like hemoglobin (p < .05, p < .01, p < .001), red blood cells (p < .01, p < .001), and platelets count (p < .01, p < .001) and decreased in spleen weight (p < .01, p < .001), colon weight (p < .01, p < .001), colon weight to length ratio (p < .05, p < .01, p < .001), macroscopic score (p < .01, p < .001), adhesion score (p < .01, p < .001), diarrhea score (p < .05, p < .001), stool consistency (p < .01, p < .001), rectal bleeding score (p < .05, p < .01, p < .001), white blood cells count (p < .01, p < .001). NG significantly (p < .01, p < .001) increased colonic superoxide, glutathione, and catalase levels and decreased malondialdehyde and myeloperoxidase levels. It also significantly (p < .01, p < .001) decreased the biochemical parameters, proinflammatory cytokines and reduced the histological damage in the colon tissue caused by TNBS.Conclusion: Our results demonstrated that NG treatment attenuated pathologic changes of TNBS-induced colitis in rats through restoring colonic damage and reducing inflammatory response in the colon tissue. Thus, NG might be considered as an effective candidate for the treatment of UC patients.

The underlying mechanism of A-type procyanidins from peanut skin on DSS-induced ulcerative colitis mice by regulating gut microbiota and metabolism

Ulcerative colitis (UC) is a kind of inflammatory bowel disease. Procyanidins have been found to prevent UC. However, most research has been focused on the alleviation effect of B-type procyanidins on UC and ignored those of A-type procyanidins. Hence, this study aims to investigate the anti-UC effect and the potential mechanism of A-type procyanidins by combining gut microbiome and metabolic profile. UC was induced by dextran sulfate sodium (DSS) in Balb/c mice, and then the mice were administrated with peanut skin procyanidins (PSP; rich in A-type procyanidins) for 9 days. Administration of PSP can ameliorate DSS-induced UC by mediating the intestinal barrier, the expression of inflammatory cytokines (TNF-α, IL-β, IL-6, and IL-10) and oxidative stress (MDA, T-SOD, NO, and iNOS) in mice. We observed that PSP affects the gut microbiota and colon metabolomic patterns of mice. The 16S rDNA sequencing showed increase in abundance of Lachnospiraceae_NK4A136_group, Oscillibacter and Roseburia and decrease of Bacteroides, Helicobacter, Parabacteroides, Escherichia-Shigella, and Enterobacter after PSP treatment. The colon tissue metabolome was significantly altered, as reflected by regulating taste transduction, mTOR signaling pathway, PI3K-Akt signaling pathway, and FoxO signaling pathway to improve the protection against UC. PRACTICAL APPLICATIONS: We investigated the anti-ulcerative colitis (UC) effect and its potential mechanism of peanut skin procyanidins (PSP). This suggests that PSP with abundant A-type procyanidins may be an effective candidate for dietary supplementation to alleviate the symptoms of UC by regulating gut microbiota and metabolism.

Aloe vera mitigates dextran sulfate sodium-induced rat ulcerative colitis by potentiating colon mucus barrier

ETHNOPHARMACOLOGICAL RELEVANCE

Aloe vera (L.) Burm. f. (Aloe vera) is a medicinal herb that used in Traditional Chinese Medicine (TCM) practice for the treatment of gastrointestinal diseases such as constipation and colitis. Recent studies also reported its beneficial effect in mitigating ulcerative colitis (UC). Nevertheless, the underlying mechanisms of Aloe vera against UC remain largely unknown.

AIM OF THE STUDY

This study aimed to explore a relation between the therapeutical effects of Aloe vera in UC and colonic mucus secretion, and further investigate the underlying pathways through which Aloe vera regulates colon mucus as well as preliminarily studied the main active constitute of Aloe vera to alleviate UC.

MATERIALS AND METHODS

UPLC-MS/MS were employed to analyze the Aloe vera extract. The rat models of UC were induced by free subjected to fresh 3% dextran sulfate sodium (DSS) solution for 8 days and then accessed to tap water for 2 days. Aloe vera extract (18 mg/kg and 72 mg/kg) or 5-ASA (400 mg/kg) was administered orally from day 1-10. At the end of experiment, rats were sacrificed and the colon tissues were harvested for analysis. UC symptoms was evaluated by disease activity index (DAI), colon length and H&E staining. The Alcian blue stain were determined colon mucus layer. Myeloperoxidase (MPO) activity, mucin and inflammatory cytokines in colon tissues were determined by ELISA. The expression of related proteins on PI3K/AKT and PKC/ERK signaling pathway was analyzed by Western blot. We then evaluated the effects of three main components of Aloe vera (Aloe-emodin, aloin A and B) on mucin secretion and cytokine expression in vitro by ELISA.

RESULTS

Oral supplement with Aloe vera extract resulted in a significantly decreased DSS-induced UC symptoms, including decreased DAI, prevention of the colon length shortening, and alleviation of the pathological changes occurring in colon. The expression of colonic pro-inflammatory mediators, including IL-6, IL-1β and TNF-α were suppressed, yet the expression of IL-10 was up-regulated by Aloe vera treatment. Moreover, Aloe vera significantly up-regulated the expressions of mucin proteins (e.g., MUC2 and MUC5AC) and increased the thickness of mucus layer in the colon. Further, we revealed that Aloe vera significantly upregulated p-PKC and p-ERK expression and downregulated p-PI3K and p-AKT expression. Finally, we discovered that treat with aloin A markedly decreased IL-6 levels and increased MUC2 expression in LPS-stimulated LS174T cell.

CONCLUSION

These results support that Aloe vera improved UC by enhancing colon mucus barrier functions in addition to reducing inflammation. Moreover, aloin A might be a main active components of Aloe vera to ameliorate UC.

Natural-Derived Polysaccharides From Plants, Mushrooms, and Seaweeds for the Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic inflammatory disease impairing the gastrointestinal tract, and its incidence and prevalence have been increasing over time worldwide. IBD greatly reduces peoples' quality of life and results in several life-threatening complications, including polyp, toxic colonic dilatation, intestinal perforation, gastrointestinal bleeding, and cancerization. The current therapies for IBD mainly include drugs for noncritical patients and operation for critical patients. However, continuous use of these drugs causes serious side effects and increased drug resistance, and the demand of effective and affordable drugs with minimal side effects for IBD sufferers is urgent. Natural-derived polysaccharides are becoming a research hotspot for their therapeutic effects on IBD. This study focuses on the research progress of various natural polysaccharides from plants, seaweeds, and mushrooms for the treatment of IBD during recent 20 years. Regulation of oxidative stress, inflammatory status, gut microbiota, and immune system and protection of the intestinal epithelial barrier function are the underlying mechanisms for the natural-derived polysaccharides to treat IBD. The excellent efficacy and safety of polysaccharides make them promising candidates for IBD therapy.

Effects of Kolaviron on Pneumonia-like Infection Induced in Albino Wistar Rats

BACKGROUND

Pneumonia is an acute or chronic inflammatory disorder of the lungs, affecting the mucosal areas of the lung. It can be caused by bacteria, viruses or fungi. In some cases, it may be caused by physical or chemical irritants. Kolaviron, a natural bioflavonoid extract from Garcinia kola seeds, has been shown to possess anti-inflammatory properties in Flu-like conditions which are associated with cough. There has been a paucity of information on the likelihood of the effectiveness of kolaviron against pneumonia infections.

OBJECTIVE

To evaluate the antibacterial and anti-inflammatory effects of kolaviron on albino Wistar rats induced with pneumonia using Klebsiella pneumonia.

MATERIALS AND METHODS

Powdered Garcinia kola seeds were extracted with n-hexane and 100% methanol as solvents by using Soxhlet extractor. A standard method was used to obtain kolaviron from the seed extracts. A total of 24 albino Wistar rats were randomly divided into six groups A to F, each comprising four rats. The rats were allowed to acclimatize for 1 hour in very cold environments using ice packs. A standardized 1.0 x10 ^-5 mg/ml culture suspension was intranasally inoculated to the rats for 10 days to induce pneumonia-like symptoms. Thereafter, the kolaviron was administered to the rats such that a 500mg/kg kolaviron extract was given once daily to groups A (male rats) and B (female rats). Groups C (male rats) and D (female rats) received 250mg/kg of kolaviron extract once daily, while group E rats were given 0.5 ml of dimethyl sulfoxide (DMSO) once daily, which served as the negative control. The rats in Group F received 2.86 mg/kg of ofloxacin once daily and served as the positive control. All the treatments were done for a period of 5 days. Then 10 days after the treatments, the animals were sacrificed and the lungs were harvested for hydrostatic lung test and histopathological examination. An overnight broth culture of Klebsiella pneumonia was streaked in sterile molten nutrient agar maintained at 37°C for 24hrs. Later, a stock of 500mg/ml of kolaviron was prepared in DMSO. Two-fold dilutions were performed to obtain the following concentrations of 100%, 50%, 25%, 12.5%, 6.25%, 3.125%, and 1.565% with the stock. The anti-Klebsiella pneumonia activity of the kolaviron extract was determined using agar well diffusion methods and incubation was done at 37 o C for 24 hrs. Student t-test and Oneway Analysis of variance (ANOVA) were used for comparison of mean differences between and among the groups.

RESULTS AND DISCUSSION

The sensitivity of Klebsiella pneumonia to kolaviron was concentration- dependent. There was an increase in anti-Klebsiella pneumonia activity with a decrease in kolaviron concentration. Kolaviron (KV), at 500mg/kg concentration, was efficacious and showed significant anti-inflammatory effects (P<0.0001). This was also confirmed in the histopathological examinations. The 3.125% concentration of the kolaviron gave IZDs that ranged from 25.68±3.33 mm on day 1 to 27.33±2.78 mm on day 5. Treatment with kolaviron showed to be sex-dependent with a significant difference (p<0.0001), when pre-treatment and post-treatment effects were compared between male and female rats.

CONCLUSION

Kolaviron can be used as an agent in the treatment of pneumonia as it possesses anti- inflammatory and anti-Klebsiella pneumonia activities.

Mechanism of Huang-lian-Jie-du decoction and its effective fraction in alleviating acute ulcerative colitis in mice: Regulating arachidonic acid metabolism and glycerophospholipid metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

Huang-lian-Jie-du decoction (HLJDD) is a traditional Chinese medicine prescription for clearing away heat, purging fire and detoxifying, which can be used to treat sepsis, stroke, Alzheimer's disease and gastrointestinal diseases. Our previous studies have shown that HLJDD can effectively alleviate acute ulcerative colitis (UC) in mice, and its n-butanol fraction (HLJDD-NBA) is the effective fraction. The aim of this study is to further investigate the mechanism of HLJDD and HLJDD-NBA in relieving UC in mice from a holistic perspective.

METHODS

The acute UC model of BABL/c mice was induced by 3.5% (w/v) dextran sodium sulfate drinking water. At the same time of modeling, HLJDD and HLJDD-NBA were given orally for treatment respectively. During the experiment, the clinical symptoms of mice were recorded and the physiological and biochemical indexes of mice were detected after the experiment. In addition, the plasma metabolites of mice in each group were detected and analyzed by ultra-high performance liquid chromatography quadrupole time of flight mass spectrometry and multivariate statistical analysis method. Then, the potential target metabolic pathway of drug intervention was screened through the enrichment analysis of differential metabolites. Finally, we use molecular simulation docking technology to further explore the molecular regulatory mechanism of HLJDD and HLJDD-NBA on potential target metabolic pathways.

RESULTS

HLJDD and HLJDD-NBA intervention can significantly reduce the disease activity index of UC mice, inhibit colon length shortening and pathological damage, and relieve the abnormal changes of physiological and biochemical parameters of UC mice. Moreover, HLJDD and HLJDD-NBA can significantly inhibit the metabolic dysfunction of UC mice by reversing the abnormal changes of 24 metabolites in UC mice, and the arachidonic acid metabolic pathway and glycerophospholipid metabolic pathway are the target metabolic pathways regulated by them. Further literature review and molecular simulation docking analysis showed that HLJDD and HLJDD-NBA may inhibit the disorder of arachidonic acid metabolism pathway and glycerophospholipid metabolism pathway by inhibiting COX-2 protein expression and PLA2, 5-LOX activity.

CONCLUSIONS

Our experiments revealed that HLJDD and HLJDD-NBA can alleviate UC of mice by regulating arachidonic acid metabolism and glycerophospholipid metabolism, which points out the direction for further research and development of HLJDD as a new anti-ulcer drug.

Huang-Lian-Jie-Du Decoction Ameliorates Acute Ulcerative Colitis in Mice via Regulating NF-κB and Nrf2 Signaling Pathways and Enhancing Intestinal Barrier Function

Evidence shows that intestinal inflammation, oxidative stress, and injury of mucosal barrier are closely related to the pathogenesis of ulcerative colitis (UC). Huang-lian-Jie-du Decoction (HLJDD) is a well-known prescription of traditional Chinese medicine with anti-inflammatory and antioxidative activities, which may be used to treat UC. However, its therapeutic effect and mechanism are still unclear. In this study, the UC model of BABL/c mice were established by DSS [3.5% (w/v)], and HLJDD was given orally for treatment at the same time. During the experiment, the clinical symptoms of mice were scored by disease activity index (DAI). Besides, the effects of HLJDD on immune function, oxidative stress, colon NF-κB and Nrf2 signaling pathway, and intestinal mucosal barrier function in UC mice were also investigated. The results showed that HLJDD could alleviate body weight loss and DAI score of UC mice, inhibit colonic shortening and relieve colonic pathological damage, and reduce plasma and colon MPO levels. In addition, HLJDD treatment significantly up-regulated plasma IL-10, down-regulated TNF-α and IL-1β levels, and inhibited the expression of NF-κB p65, p-IκKα/β, and p-IκBα proteins in the colon. Moreover, NO and MDA levels in colon tissues were significantly reduced after HLJDD treatment, while GSH, SOD levels and Nrf2, Keap1 protein expression levels were remarkably elevated. Additionally, HLJDD also protected intestinal mucosa by increasing the secretion of mucin and the expression of ZO-1 and occludin in colonic mucosa. These results indicate that HLJDD could effectively alleviate DSS-induced mice UC by suppressing NF-κB signaling pathway, activating Nrf2 signaling pathway, and enhancing intestinal barrier function.

Role of allopurinol and febuxostat in the amelioration of dextran-induced colitis in rats

Ulcerative colitis is a chronic auto-inflammatory disorder confined to the colorectal region. It is challenging to find an absolute treatment and current therapy aims to ameliorate symptoms, decrease relapses and prevent prognosis of colorectal cancer. In the present study, we investigated the possible action of xanthine oxidase inhibitors in murine colitis model by measuring different indicative parameters and comparing the results to those of the reference sulfasalazine. Also, we compared the effects of combining sulfasalazine and allopurinol to each drug alone. Dextran Sodium Sulfate (DSS) is used in this study to induce ulcerative colitis in male wistar rats as it is known to be the closest model that mimics human ulcerative colitis. Allopurinol was given prior to colitis induction by four days and febuxostat for six days before induction with DSS (5% w/v) and continue to give them concomitantly during the induction.Il-1β, malondialdehyde, reduced glutathione (GSH), xanthine oxidase, and superoxide dismutase were measured in colonic tissue. We also measured concentrations of IL-1β, Il-6 and uric acid in serum. Allopurinol dose-dependently ameliorated biochemical injuries. Febuxostat has shown better results than allopurinol and sulfasalazine, and this is the first study to demonstrate this.

3-(1H-Benzo[d]imidazol-6-yl)-5-(4-fluorophenyl)-1,2,4-oxadiazole (DDO7232), a Novel Potent Nrf2/ARE Inducer, Ameliorates DSS-Induced Murine Colitis and Protects NCM460 Cells against Oxidative Stress via ERK1/2 Phosphorylation

Ulcerative colitis (UC) is a common inflammatory bowel disease that can destroy the integrity of the colon and increase the risk of colorectal cancer. Oxidative stress is one of the critical pathogenic factors for UC, further impairing the entire affected colon. The Nrf2-ARE signaling pathway plays an important role in counteracting oxidative and electrophilic stress. Activation of the Nrf2-ARE pathway provides an indispensable defense mechanism for the treatment of UC. In this study, we identified a novel effective Nrf2 activator, DDO7232, which showed protective effects on NCM460 cells and therapeutic effects on DSS-induced colitis in mice. Mechanistic studies indicated that the Nrf2-ARE-inducing activity of DDO7232 was based on the activation of the ERK1/2 phosphorylation. The phosphorylation of Nrf2 Ser40 by p-ERK triggered the transport of Nrf2 into the nucleus and drove the expression of Nrf2-dependent antioxidant proteins. These results not only revealed the antioxidant mechanisms of DDO7232 but also provided an effective therapeutic option for the treatment of UC.

Dandelion root extract protects NCM460 colonic cells and relieves experimental mouse colitis

The protective potential of dandelion on acute hepatitis, lung injury and colorectal cancer has recently been revealed. Importantly, ulcerative colitis (UC), a clinically defined inflammatory bowel disease, accelerates the risk of colorectal cancer. However, studies focusing on the activity of dandelion on UC are extremely limited. In the present study, we found that an aqueous extract of dandelion root increases cell viability and decreases apoptosis in dextran sodium sulfate (DSS)-incubated NCM460 human colonic epithelial cells, probably through removing the production of reaction oxygen species and blocking nuclear factor-kappaB signaling. We then examined the anti-colitis efficacy of this extract in an in vivo study. We detected that dandelion root extract efficiently ameliorates progressive acute injury as demonstrated by a reduction in body weight loss, severity scores of disease index and shortened colon length during DSS treatment, as well as reducing the inflammatory conditions and oxidative stress in the colon of DSS-induced mice. Our study clearly demonstrates that dandelion has a strong cytoprotective effect on NCM460 colonocytes and shows powerful defense on an established experimental mouse model of DSS-induced UC. Therefore, dandelion root extract can be an effective anti-colitis complex mixture and can provide a complementary alternative to currently available therapeutic intervention in UC.

An inhibitor of the Keap1-Nrf2 protein-protein interaction protects NCM460 colonic cells and alleviates experimental colitis

Ulcerative colitis (UC) is a chronic relapsing-remitting form of inflammatory bowel disease (IBD) that increases the risk of colorectal cancer, the third most common malignancy in humans. Oxidative stress is a risk factor for the development of UC. The Keap1-Nrf2-ARE pathway is one of the most important defensive mechanisms against oxidative and/or electrophilic stresses. In this study, we identified CPUY192018 as a potent small-molecule inhibitor of the Keap1-Nrf2 PPI, investigated the cyto-protective effects of CPUY192018 on the NCM460 colonic cells and evaluated whether treatment with the inhibitor of the Keap1-Nrf2 PPI exerts protection on an established experimental model of UC induced by dextran sodium sulfate (DSS). Our study clearly demonstrated that CPUY192018 had a cytoprotective effect against DSS in both NCM460 cells and mouse colon via the activation of Nrf2 signaling. These results suggested that activation of Nrf2 by directly inhibiting the Keap1-Nrf2 PPI may be beneficial as a treatment for UC.

Red wine polyphenol extract efficiently protects intestinal epithelial cells from inflammation via opposite modulation of JAK/STAT and Nrf2 pathways

The development of therapeutic approaches combining efficacy and safety represents an important goal in intestinal inflammation research. Recently, evidence has supported dietary polyphenols as useful tools in the treatment and prevention of chronic inflammatory diseases, but the mechanisms of action are still poorly understood. We here reveal molecular mechanisms underlying the anti-inflammatory action of a non-alcoholic polyphenol red wine extract (RWE), operating at complementary levels via the Janus kinase/signal transducer and activator of transcription (JAK/STAT) and Nuclear factor-erythroid 2-related factor-2 (Nrf2) pathways. RWE significantly reduced the nuclear levels of phosphorylated STAT1 and also the cellular levels of phosphorylated JAK1 induced by cytokines, suppressing the JAK/STAT inflammatory signalling cascade. In turn, RWE increased the Nrf2 nuclear level, activating the Nrf2 pathway, leading not only to an up-regulation of the heme oxygenase-1 (HO-1) expression but also to an increase of the glutamate-cysteine ligase subunit catalytic (GCLc) gene expression, enhancing the GSH synthesis, thereby counteracting GSH depletion that occurs under inflammatory conditions. Overall, data indicate that the anti-inflammatory action of RWE is exerted at complementary levels, via suppression of the JAK/STAT inflammatory pathway and positive modulation of the activity of Nrf2. These results point to the potential use of the RWE as an efficient, readily available and inexpensive therapeutic strategy in the context of gastrointestinal inflammation.

Methylene Blue inhibits the inflammatory process of the acetic acid-induced colitis in the rat colonic mucosa

Inflammatory bowel disease is a serious health problem. Although it has been widely investigated, treatment of inflammatory bowel diseases currently remains as a challenging clinical problem. Over production of nitric oxide has been demonstrated to cause tissue damage and inflammation. In this study, the effect of methylene blue (MB), a well-known inhibitor of nitric oxide synthesis, was investigated in acetic acid (AA)-induced colitis model in Sprague-Dawley rats. Eighty male rats randomized into 4 groups (control, control MB, colitis, colitis + MB). AA was applied to groups 3 and 4. MB was added into group 2 and 4. Three days later, animals were sacrificed and 8 cm distal colonic segment resected and the specimens are examined using macroscopical, histological, and biochemical methods. The results of the macroscopic and microscopic examination showed that in group 4 the mucosal damage and inflammation score significantly lower than group 3. Increased intestinal permeability in acetic acid-administered group was significantly reversed by MB application. Myeloperoxidase activity and malondialdehyde levels increased significantly, while superoxide dismutase and catalase activities were suppressed after AA-administration. These biochemical parameters were reversed in MB-treated group. Administration of acetic acid resulted in increased levels of tumor necrosis factor-α, interleukin-1β, interleukin-6, total nitrite/nitrate levels and nitric oxide synthase activity. These biochemical alterations were significantly reversed by MB application also. In conclusion, our results indicate that MB decreases the level of nitric oxide and decreases inflammation in acetic acid-induced colitis.

Bone marrow-derived mesenchymal stem cell transplantation ameliorates oxidative stress and restores intestinal mucosal permeability in chemically induced colitis in mice

BACKGROUND

Ulcerative colitis (UC) can be viewed as an autoimmune disease. Bone marrow-derived mesenchymal stem cells (MSCs) with its regenerative, cellular multi-lineage and immunomodulatory abilities can influence the repair of damaged tissues in UC. This study investigated the effects of MSCs transplantation on the mice intestinal barrier in response to oxidative stress injury.

METHODS

Colitis was induced by daily consecutive administration of 5% dextran sulfate sodium (DSS) solution for 7 days. Male murine MSCs were isolated and transplanted into female mice via injection in the tail vein. Serum and colon specimens were collected at 12 h, 24 h, 3 d, 7 d and 14 d after injection. Serum levels of D-lactate (D-LAC), diamine oxidase (DAO), colonic levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were quantified. The SRY protein of the male sex determinant gene expression and E-cadherin were also ascertained intracellularly.

RESULTS

Three days after receiving male MSCs transplantation, SRY protein expression was detected. The quantity increased on successive days. Serum levels of D-LAC and DAO, colonic MDA and SOD normalized in a shorter time period compared to controls (p<0.05). Not surprisingly, histological regeneration of tissue and E-cadherin expression in the colon of MSCs transplanted mice also occurred in a shorter time period than controls.

CONCLUSIONS

Transplanted MSCs restored mucosal permeability, and minimized oxidative stress related injury.

Kolaviron, a natural antioxidant and anti-inflammatory phytochemical prevents dextran sulphate sodium-induced colitis in rats

The beneficial effects of kolaviron, a natural biflavonoid from the seeds of Garcinia kola, have been attributed mainly to its antioxidant and anti-inflammatory effects. This study investigated these effects on dextran sulphate sodium (DSS)-induced ulcerative colitis in rats. Sulfasalazine served as standard reference in this study. Kolaviron and sulfasalazine were separately co-administered orally at 200 mg/kg and 500 mg/kg, respectively, to dextran sulphate sodium-exposed rats for 5 days. The result indicated that kolaviron or sulfasalazine significantly prevented DSS-induced body weight loss as well as the incidence of diarrhoea and bleeding in DSS-exposed rats. Kolaviron suppressed the DSS-mediated increase in colonic nitric oxide concentration and myeloperoxidase activity and significantly prevented the increase in inflammatory mediators, interleukin-1β and tumour necrosis factor alpha, in the colon of DSS-treated rats. The significant depletion in colonic antioxidant status in rats exposed to DSS alone was evident by marked reduction in colonic catalase and glutathione S-transferase activities as well as glutathione content, leading to elevated hydrogen peroxide and lipid peroxidation levels. Histopathologically, DSS alone resulted in severe epithelial erosion, total absence of goblet cells, destruction of the crypts, necrotic and distorted glands, accompanied by marked cellular mononuclear cells infiltration. However, administration of kolaviron and sulfasalazine ameliorated DSS-induced colitis by increasing the antioxidant status decreased hydrogen peroxide and lipid peroxidation levels and attenuated the adverse effect of DSS on colon architecture. In conclusion, the anti-colitis effect of kolaviron is related to its intrinsic anti-inflammatory and anti-oxidative properties.

Intestinal anti-inflammatory activity of red wine extract: unveiling the mechanisms in colonic epithelial cells

The development of new therapeutic approaches, combining efficacy and safety against intestinal inflammation, notably inflammatory bowel disease (IBD), has emerged as an important goal due to the significant side effects and the lack of effectiveness of standard current therapies. Recently, several studies described the health-promoting effects of red wine, including anti-inflammatory properties, but the molecular mechanisms underlying its beneficial role remain largely unknown. Red wine is rich in phenolic compounds and it has been suggested that the positive effect of red wine intake might be attributed not only to the antioxidant properties of these compounds but also to the modulation of signalling cascades in connection with physiological and pathophysiological conditions such as inflammatory processes. This study assesses the potential anti-inflammatory action of a red wine extract (RWE) enriched in polyphenols in a cellular model of intestinal inflammation using cytokines-stimulated HT-29 colon epithelial cells. RWE suppressed cytokines-induced IκB degradation and interleukin-8 production in a dose-dependent manner. Coherently, key inflammatory mediators downstream NF-κB activation; notably cyclooxygenase-2 and inducible nitric oxide synthase were maintained at low levels by RWE in the presence of the cytokines. Additionally, RWE inhibited both the increase of nitric oxide derived from iNOS and of protein tyrosine nitration, a biomarker of nitrosative stress that typically requires the reaction of nitric oxide with the superoxide radical. Taken together, the anti-inflammatory action of RWE, mechanistically supported by the modulation of cascades orchestrated by NF-κB and involving nitric oxide, suggests that RWE (a readily straightforward preparation when compared with the purification of specific compounds) may represent a simple and inexpensive therapeutic strategy in the context of intestinal inflammation.

Establishment and validation of a new semi-chronic dextran sulfate sodium-induced model of colitis in mice

BACKGROUND

The dextran sulfate sodium (DSS)-induced model of colitis is a commonly used model of inflammatory bowel disease (IBD) in animals. However, there were few studies on the therapeutic efficacy of drugs for IBD after the onset of colitis in this model. We established a semi-chronic model of DSS-induced colitis in mice and used it to assess the therapeutic efficacy of agents for IBD.

MATERIALS AND METHODS

Colitis was induced by administration of 3% DSS in drinking water to mice for 7days followed by 5days of normal drinking water.

RESULTS

Ulcerative colitis (UC)-like symptoms including diarrhea, bloody stools and body-weight loss were observed from days 3 to 5, and continued until day 12 after DSS administration. Persistent colitis was associated with sustained local production of cytokines and was characterized by infiltration of inflammatory cells, crypt loss and erosion in the distal colon. These features are similar to those found in patients with UC. In this model, anti-tumor necrosis factor (TNF)-α antibody or anti-interleukin (IL)-12/23p40 antibody significantly ameliorated colitis when administered after the onset of colitis. However, treatment with FK506, prednisolone or sulfasalazine provided limited therapeutic benefit.

CONCLUSION

The DSS-induced colitis established here showed similar symptomatic and histopathological features to those seen in human UC. This model may be available for predicting the clinical efficacy of candidate compounds for UC.

BTZO-15, an ARE-activator, ameliorates DSS- and TNBS-induced colitis in rats

Inflammatory bowel disease (IBD) is a group of chronic inflammatory disorders that are primarily represented by ulcerative colitis and Crohn's disease. The etiology of IBD is not well understood; however, oxidative stress is considered a potential etiological and/or triggering factor for IBD. We have recently reported the identification of BTZO-1, an activator of antioxidant response element (ARE)-mediated gene expression, which protects cardiomyocytes from oxidative stress-induced insults. Here we describe the potential of BTZO-15, an active BTZO-1 derivative for ARE-activation with a favorable ADME-Tox profile, for the treatment of IBD. BTZO-15 induced expression of heme oxygenase-1 (HO-1), an ARE-regulated cytoprotective protein, and inhibited NO-induced cell death in IEC-18 cells. Large intestine shortening, rectum weight gain, diarrhea, intestinal bleeding, and an increase in rectal myeloperoxidase (MPO) activity were observed in a dextran sulfate sodium (DSS)-induced colitis rat model. Oral administration of BTZO-15 induced HO-1 expression in the rectum and attenuated DSS-induced changes. Furthermore BTZO-15 reduced the ulcerated area and rectal MPO activity in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis rats without affecting rectal TNF-α levels. These results suggest that BTZO-15 is a promising compound for a novel IBD therapeutic drug with ARE activation properties.