Radical induction theory of ulcerative colitis

The potential protective effect of Camellia Sinensis in mitigating monosodium glutamate-induced neurotoxicity: biochemical and histological study in male albino rats

Monosodium glutamate (MSG) is the sodium compound derived from glutamic acid. Excessive daily ingestion of MSG leads to elevated amounts of glutamic acid in the bloodstream, which can be detrimental to brain structures. Camellia sinensis, often known as green tea (GT), is a rich source of essential hexogen antioxidants that are necessary for the body. Thirty-two adult male albino rats were divided into four groups (n = 8). Group 1 served as a control -ve group. Group 2 was given GT (1.5 ml/rat/day). Group 3 was given MSG (600 mg/kg/day). Group 4 was given MSG (600 mg/kg/day) and GT (1.5 ml/rat/day). All treatments were given orally for 28 days. MSG administration resulted in significant neurotoxicity in rats that was revealed by the significant reduction of serum concentration of glutathione peroxidase (GPx) and nitric oxide (NO), and the significant elevation of total antioxidant capacity (TAC) accompanied by the significant reduction of levels of serum monoamines (dopamine, serotonin, and norepinephrine) and histological changes in the hippocampus area CA1, dentate gyrus, and cerebellar cortex and positive immunohistochemical staining of glial fibrillary acidic proteins (GFAP) and calretinin. Administration of GT with MSG counteracted the MSG-mediated oxidative stress by significantly increasing serum concentrations of GPX and NO and significantly decreasing concentrations of TAC. Furthermore, GT significantly increased levels of serum monoamines (dopamine, serotonin, and norepinephrine). Moreover, it ameliorated the histological changes, GFAP, and calretinin immunostaining in brain tissues. It is envisaged that GT will serve as a viable protective choice for the inclusion of the neurotoxicity treatment procedure.

Oxidative stress in dogs with chronic inflammatory enteropathy treated with allogeneic mesenchymal stem cells

The search for new biomarkers in patients with chronic inflammatory enteropathy (CIE) is ongoing in the human and veterinary medicine fields. Oxidative stress biomarkers (malondialdehyde [MDA], reduced glutathione [GSH], and albumin) have been studied in humans with chronic enteropathies, but among them, only albumin has been studied in dogs with CIE. Moreover, the effect of mesenchymal stem cell (MSCs) treatment with or without prednisone on these parameters has never been studied in dogs with CIE. These parameters were compared between healthy dogs (n = 12) and dogs with CIE, and before and 1, 3, 6, and 12 months after the treatment with MSCs alone (n = 9) or together with prednisone (n = 11). The relationship between the Canine Inflammatory Bowel Disease Activity Index (CIBDAI) and oxidative stress was evaluated. Albumin was the only parameter that significantly differed between dogs with CIE and healthy dogs (p = 0,037). Differences were observed only in albumin values after combined treatment with MSCs and prednisone. No differences were observed in MDA and GSH after treatment with MSCs with or without prednisone. Albumin could help stage canine CIE, as well as its prognosis, as has already been demonstrated, although it is essential to evaluate this parameter for its antioxidant capacity, and therefore it could be a good biomarker of oxidative stress in this pathology. However, the treatment with MSCs seems unable to modify any of the analyzed oxidative stress parameters.

Identified S100A9 as a target for diagnosis and treatment of ulcerative colitis by bioinformatics analysis

Ulcerative colitis (UC) is a chronic, recurrent inflammatory bowel disease. UC confronts with severe challenges including the unclear pathogenesis and lack of specific diagnostic markers, demanding for identifying predictive biomarkers for UC diagnosis and treatment. We perform immune infiltration and weighted gene co-expression network analysis on gene expression profiles of active UC, inactive UC, and normal controls to identify UC related immune cell and hub genes. Neutrophils, M1 macrophages, activated dendritic cells, and activated mast cells are significantly enriched in active UC. MMP-9, CHI3L1, CXCL9, CXCL10, CXCR2 and S100A9 are identified as hub genes in active UC. Specifically, S100A9 is significantly overexpressed in mice with colitis. The receiver operating characteristic curve demonstrates the excellent performance of S100A9 expression in diagnosing active UC. Inhibition of S100A9 expression reduces DSS-induced colonic inflammation. These identified biomarkers associated with activity in UC patients enlighten the new insights of UC diagnosis and treatment.

Aqueous extracts of Ocimum gratissimum mitigate colitis and protect against AOM/DSS-induced colorectal cancer in mice

In this study, we explored the in vivo effects of Ocimum gratissimum aqueous extracts (OGE) on colorectal cancer (CRC) development provoked by azoxymethane/dextran sodium sulfate (AOM/DSS). The results showed a significant reduction in the tumor load and tumor number for the OGEH group that received continued administration of OGE compared to the AOM/DSS group, with P values of <0.01, but this was not observed in the OGEHs group that received separated administration of OGE. All groups except the control group exhibited aberrant crypt foci (ACF) and adenocarcinoma of lesion pathology in colon, and both conditions were significantly reduced in the OGEH group (P < 0.01) as compared to the AOM/DSS group. Subsequent investigation into whether OGE exhibits eliminative effects on DSS-induced severe colitis (SC) in mice showed that the disease activity index score was significantly reduced in the OGE-treated groups (P < 0.01), also colon colitis histological score was reversed. These data suggest that OGE may be potentially effective in preventing CRC when administered throughout the promotional stages of carcinogenesis by inhibiting inflammatory SC.

Protective effect of Arum maculatum against dextran sulfate sodium induced colitis in rats

Ulcerative colitis (UC) is an inflammatory disease of the large intestine that is characterized by diarrhea, bloody stools, abdominal pain and mucosal ulceration. UC is treated with nonsteroidal anti-inflammatory drugs, corticosteroids or immunosuppressants, but long-term use of these drugs can cause adverse effects. Arum maculatum is used as a traditional treatment for digestive system disorders, but its use for treatment of UC has not been investigated rigorously. We investigated the possible protective effect of a methanol extract of A. maculatum against dextran sulfate sodium (DSS) induced experimental UC in rats. Total phenolic and flavonoid contents of the extract were 32.919 ± 1.125 mg gallic acid equivalent (GAE)/g and 52.045 ± 7.902 µg rutin equivalent (RE)/mg, respectively. The half-maximal inhibitory concentration (IC50) for the extract was 105.76 µg/ml according to the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity assay. Effects of A. maculatum extract on UC induced by DSS were assessed both macroscopically and histologically. We also investigated effects of A. maculatum extract on malondialdehyde (MDA) levels and the oxidative stress index (OSI) in normal rats and rats with UC. We found that treatment with A. maculatum extract protected the colon against DSS induced UC in a dose-dependent manner.

Mucin levels in glands of the colonic mucosa of rats with diversion colitis subjected to enemas containing sucralfate and n-acetylcysteine alone or in combination

PURPOSE

To evaluate the tissue content of neutral and acidic mucins, sulfomucins and sialomucins in colonic glands devoid of intestinal transit after enemas containing sucralfate and n-acetylcysteine alone or in combination.

METHODS

Sixty-four rats underwent intestinal transit bypass. A colonic segment was collected to compose the white group (without intervention). After derivation, the animals were divided into two groups according to whether enemas were performed daily for two or four weeks. Each group was subdivided into four subgroups according to the substance used: control group: saline 0.9%; sucralfate group (SCF): SCF 2 g/kg/day; n-acetylcysteine group (NAC): NAC 100 mg/kg/day; and SCF+NAC group: SCF 2 g/kg/day + NAC 100 mg/kg/day.Neutral and acidic mucins were stained by periodic acid-Schiff and alcian-blue techniques, respectively. The distinction between sulfomucins and sialomucin was made by the high alcian-blue iron diamine technique. The content of mucins in the colonic glands was measured by computerized morphometry. The inflammatory score was assessed using a validated scale. The results between the groups were compared by the Mann-Whitney's test, while the variation according to time by the Kruskal-Wallis' test (Dunn's post-test). A significance level of 5% was adopted.

RESULTS

There was reduction in the inflammatory score regardless of the application of isolated or associated substances. Intervention with SCF+NAC increased the content of all mucin subtypes regardless of intervention time.

CONCLUSIONS

The application of SCF+NAC reduced the inflammatory process of the colonic mucosa and increased the content of different types of mucins in the colonic glands of segments excluded from fecal transit.

Cellular Red-Ox system in health and disease: The latest update

Cells are continually exposed to reactive oxygen species (ROS) generated during cellular metabolism. Apoptosis, necrosis, and autophagy are biological processes involving a feedback cycle that causes ROS molecules to induce oxidative stress. To adapt to ROS exposure, living cells develop various defense mechanisms to neutralize and use ROS as a signaling molecule. The cellular redox networks combine signaling pathways that regulate cell metabolism, energy, cell survival, and cell death. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) are essential antioxidant enzymes that are required for scavenging ROS in various cell compartments and response to stressful situations. Among the non-enzymatic defenses, vitamin C, glutathione (GSH), polyphenols, carotenoids, vitamin E, etc., are also essential. This review article describes how ROS are produced as byproducts of oxidation/reduction (redox) processes and how the antioxidants defense system is directly or indirectly engaged in scavenging ROS. In addition, we used computational methods to determine the comparative profile of binding energies of several antioxidants with antioxidant enzymes. The computational analysis demonstrates that antioxidants with a high affinity for antioxidant enzymes regulate their structures.

Mesenchymal Stem Cell-derived Exosomes: Novel Therapeutic Approach for Inflammatory Bowel Diseases

As double membrane-encapsulated nanovesicles (30-150 nm), exosomes (Exos) shuttle between different cells to mediate intercellular communication and transport active cargoes of paracrine factors. The anti-inflammatory and immunomodulatory activities of mesenchymal stem cell (MSC)-derived Exos (MSC-Exos) provide a rationale for novel cell-free therapies for inflammatory bowel disease (IBD). Growing evidence has shown that MSC-Exos can be a potential candidate for treating IBD. In the present review, we summarized the most critical advances in the properties of MSC-Exos, provided the research progress of MSC-Exos in treating IBD, and discussed the molecular mechanisms underlying these effects. Collectively, MSC-Exos had great potential for cell-free therapy in IBD. However, further studies are required to understand the full dimensions of the complex Exo system and how to optimize its effects.

Protective Effect of Apple Polyphenols on H₂O₂-Induced Oxidative Stress Damage in Human Colon Adenocarcinoma Caco-2 Cells

Apple is an important dietary agent for human and apple polyphenols (AP) are the main secondary metabolites of apples. In this study, the protective effects of AP on hydrogen peroxide (H₂O₂)-induced oxidative stress damage in human colon adenocarcinoma Caco-2 cells were investigated by cell viability, oxidative stress change as well as cell apoptosis. Pre-adding AP could significantly increase the survival rate of H₂O₂-treated Caco-2 cells. Besides, the activities of antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and catalase (CAT) were elevated. While the malondialdehyde (MDA) content which is the major oxidant products of polyunsaturated fatty acids (PUFA) reduced after AP treatment. In addition, AP also suppressed the emergence of DNA fragment and decreased the expression of apoptosis-related protein Caspase-3. These results demonstrated that AP could ameliorate H₂O₂-induced oxidative stress damage in Caco-2 cells, which could serve as a reference for further studies of apple natural active products and deep study of the anti-oxidative stress mechanism.

Monosodium glutamate induces cortical oxidative, apoptotic, and inflammatory challenges in rats: the potential neuroprotective role of apigenin

Monosodium glutamate (MSG) is used as a flavor, and a taste enhancer was reported to evoke marked neuronal impairments. This study investigated the neuroprotective ability of flavonoid apigenin against neural damage in MSG-administered rats. Adult male rats were allocated into four groups: control, apigenin (20 mg/kg b.wt, orally), MSG (4 g/kg b.wt, orally), and apigenin + MSG at the aforementioned doses for 30 days. Regarding the levels of neurotransmitters, our results revealed that apigenin augmented the activity of acetylcholinesterase (AChE) markedly, and levels of brain monoamines (dopamine, norepinephrine, and serotonin) accompanied by lessening the activity of monoamine oxidase (MAO) as compared to MSG treatment. Moreover, apigenin counteracted the MSG-mediated oxidative stress by decreasing the malondialdehyde (MDA) levels together with elevating the glutathione (GSH) levels. In addition, pretreatment with apigenin induced notable increases in the activities of cortical superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR). Furthermore, apigenin attenuated the cortical inflammatory stress as indicated by lower levels of pro-inflammatory mediators such as interleukin-1 b (IL-1b), tumor necrosis factor-α (TNF-α), and nitric oxide (NO) as well as downregulated inducible nitric oxide synthase (iNOS) expression levels. Histopathological screening validated the abovementioned results and revealed that apigenin restored the distorted cytoarchitecture of the brain cortex. Thus, the present findings collectively suggest that apigenin exerted significant protection against MSG-induced neurotoxicity by enhancing the cellular antioxidant response and attenuating inflammatory machineries in the rat brain cortex.

Faba beans with enhanced antioxidant activity ameliorate acetic acid-induced colitis in experimental rats

Faba beans are among the legumes that are of the greatest importance due to their high nutritional value. In addition to the essential nutrients that faba beans contain, they also contain bioactive compounds such as phenolics and flavonoids that are considered as potent natural antioxidants. Ulcerative colitis (UC) is an inflammatory bowel disease in which oxidative stress plays an essential role in the pathophysiology. The aim of the current study was to evaluate the antioxidant activity of faba bean seeds harvested from plants grown from seeds pre-treated with selenium, garlic husk extract and/or lemon peel extract and to evaluate their in vivo effects in a rat model of UC. 54 female rats were divided randomly into nine groups (n = 9). All groups were given the different tested treatments 14 days prior to UC induction using acetic acid (intra-rectal injection of 2 ml, 4% v/v in saline). Our results revealed that the treatment of faba bean seeds with a mixture of selenium, garlic husk extract and lemon peel extract before planting led to a significant increase in selenium, nitrogen, potassium, total protein, phenolic and flavonoid content in the harvested faba bean seeds with a subsequent enhancement of their antioxidant capacity. Consumption of such faba beans showed potential protective and therapeutic effects during experimental colitis by reducing colonic oxidative stress and increasing colonic antioxidant defense mechanisms. Further research is required to understand the mechanisms by which faba beans influence colitis, their effects on various inflammatory biomarkers and their impact on the severity of colitis in humans.

Production of Corn Protein Hydrolysate with Glutamine-Rich Peptides and Its Antagonistic Function in Ulcerative Colitis In Vivo

Ulcerative colitis is a typical chronic inflammatory disease of the gastrointestinal tract, which has become a serious hazard to human health. The purpose of the present study was to evaluate the antagonistic effect of corn protein hydrolysate with glutamine-rich peptides on ulcerative colitis. The sequential hydrolysis of corn gluten meal by Alcalase and Protamex was conducted to prepare the hydrolysate, and then the mouse ulcerative colitis model induced by dextran sulfate sodium was applied to evaluate its biological activities. The results indicated that the hydrolysate significantly improved weight loss (p < 0.05), reduced the colonic shortening and the disease activity index, diminished the infiltration of inflammatory cells in the colonic tissue, and reduced the permeability of the colonic mucosa in mice. In addition, the hydrolysate decreased the contents of pro-inflammatory factors IL-1β, IL-6, and TNF-α, increased the anti-inflammatory factor IL-10 and oxidative stress markers GSH-Px and SOD in the animal tests. Moreover, the hydrolysate also regulated the abundance and diversity of the intestinal microbiota, improved the microbiota structure, and increased the content of beneficial bacteria including Lactobacillus and Pediococcus. These results indicated that the hydrolysate might be used as an alternative natural product for the prevention of ulcerative colitis and could be further developed into a functional food.

Chemistry of Hydrogen Peroxide Formation and Elimination in Mammalian Cells, and Its Role in Various Pathologies

Hydrogen peroxide (H2O2) is a compound involved in some mammalian reactions and processes. It modulates and signals the redox metabolism of cells by acting as a messenger together with hydrogen sulfide (H2S) and the nitric oxide radical (•NO), activating specific oxidations that determine the metabolic response. The reaction triggered determines cell survival or apoptosis, depending on which downstream metabolic pathways are activated. There are several ways to produce H2O2 in cells, and cellular systems tightly control its concentration. At the cellular level, the accumulation of hydrogen peroxide can trigger inflammation and even apoptosis, and when its concentration in the blood reaches toxic levels, it can lead to bioenergetic failure. This review summarizes existing research from a chemical perspective on the role of H2O2 in various enzymatic pathways and how this biochemistry leads to physiological or pathological responses.

The Anti-Inflammatory Properties of Licorice (Glycyrrhiza glabra)-Derived Compounds in Intestinal Disorders

Intestinal diseases, such as inflammatory bowel diseases (IBDs) and colorectal cancer (CRC), are a significant source of morbidity and mortality worldwide. Epidemiological data have shown that IBD patients are at an increased risk for the development of CRC. IBD-associated cancer develops against a background of chronic inflammation and oxidative stress, and their products contribute to cancer development and progression. Therefore, the discovery of novel drugs for the treatment of intestinal diseases is urgently needed. Licorice (Glycyrrhiza glabra) has been largely used for thousands of years in traditional Chinese medicine. Licorice and its derived compounds possess antiallergic, antibacterial, antiviral, anti-inflammatory, and antitumor effects. These pharmacological properties aid in the treatment of inflammatory diseases. In this review, we discuss the pharmacological potential of bioactive compounds derived from Licorice and addresses their anti-inflammatory and antioxidant properties. We also discuss how the mechanisms of action in these compounds can influence their effectiveness and lead to therapeutic effects on intestinal disorders.

Myrica salicifolia Hochst. ex A. Rich. suppress acetic acid-induced ulcerative colitis in rats by reducing TNF-alpha and interleukin-6, oxidative stress parameters and improving mucosal protection

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) with rising prevalence in developing countries, and limited success of current therapies, natural products have immense potential for therapy due to their "disease modifying and side-effect neutralizing" potential. Myrica salicifolia is traditionally used for gastrointestinal diseases and have reported antiinflammatory activities, but its use in IBD has not yet been studied. Therefore, in the present study, the effects of the root extract of M. salicifolia (Ms.Cr) were investigated using the acetic acid-induced UC model in rats. For 6 days, the rats were given either vehicle (10 mL/kg), lower (200 mg/kg), and higher (400 mg/kg) doses of Ms.Cr, or the positive control drug (prednisolone; 2 mg/kg) orally. A single dosage of 5% acetic acid (1.0 mL) was administered intrarectally to rats on day 6 to induce UC. Disease activity index (DAI), histological observations, the biochemical parameters related to oxidative stress, and specific cytokines such as interleukin-6 (IL-6) and the tumor necrosis factor-α (TNF-α) were determined to assess the effect of Ms.Cr. In comparison to the AA-induced colitis rats, Ms.Cr's pretreatment significantly decreased DAI, colonic ulceration, and inflammatory score. Total glutathione levels and catalase activity were considerably recovered in the colitis group treated with Ms.Cr, whereas enhanced lipid peroxidation in colon tissues was significantly decreased. Moreover, Ms.Cr pretreatment also caused inhibition of the activation of IL-6 and TNF-α in the colonic tissues of respective groups. Based on these findings, Ms.Cr might be developed to treat UC in the future.

Histopathological Evaluation of the Effect of Eugenol in a Model of Trinitrobenzenesulfonic Acid-Induced Colitis in Rats

Introduction: Trinitrobenzenesulfonic acid (TNBS)-induced experimental colitis in animals is a commonly used model of inflammatory bowel disease (IBD). Eugenol (Eug) is a natural phenolic compound possessing promising antioxidant and anti-inflammatory therapeutic properties.

Aim: The present study investigated the effects of Eug in a TNBS-induced rat colitis model using criteria for histopathological evaluation of the colonic damage.

Materials and methods: Male Wistar rats were divided into 6 experimental groups, each of 10 rats: Control, TNBS, TNBS+Eug1, TNBS+Eug5, TNBS+Eug25, and TNBS+Eug125 group. Eug or the solvent (sunflower oil) was applied orally using an orogastric cannula. The control group and TNBS group were treated only with sunflower oil. Eug groups were treated with corresponding doses of Eug (1, 5, 25 and 125 mg/kg) dissolved in sunflower oil. Colitis was induced by the application of TNBS in the colon. The animal treatment began 6 days before the colitis induction and continued for 8 days after it. At the end of the experiment, colitis severity was evaluated histopathologically regarding epithelium injury, inflammatory cell infiltration, and formation of granulation tissue.

Results: In all TNBS+Eug groups, the formation of granulation tissue was enhanced compared to TNBS. In group TNBS+Eug125 the difference was significant compared to the control group (p < 0.05). No significant improvement regarding the scores of epithelium injury and inflammatory cell infiltration was observed in Eug groups compared to TNBS group.

Conclusion: Eug did not improve the signs of TNBS-induced epithelial injury and inflammatory cell infiltration, but stimulated the formation of granulation tissue which might be considered as a sign of healing.

A novel role of pirfenidone in attenuation acetic acid induced ulcerative colitis by modulation of TGF-β1 / JNK1 pathway

Colon diseases are a major health burden, particularly ulcerative colitis, in both men and women worldwide. Environmental and genetic factors in various colonic pathologies influence the onset and outcome of diseases. As the evidence from recent research is considered, the importance of inflammation in the onset, progression, and outcome is gaining more traction. The goal of this study was to see if pirfenidone could treat ulcerative colitis (UC) and if so, what mechanisms were involved. By intracolonic instillation [2 ml, 3 percent v/v acetic acid (AA)], ulcerative colitis was induced. Pirfenidone was administered to rats in different experimental groups (125 or 250 and 500 mg/kg, orally) for two weeks. Compared to normal group, the AA group showed an increase in colon weight, length, body weight, clinical evaluation, and macroscopic scoring of UC, serum lactate dehydrogenase, C-reactive protein, malondialdehyde, while decreasing serum total antioxidant capacity. Significant increases in colon Jun N terminal kinase1 (JNK1), transforming growth factor-beta (TGF-β1), interleukin 1 beta (IL1β), and Caspase-3 content. Furthermore, immunohistochemical staining revealed increased nuclear factor kappa B (NF-κB) expression along with histopathological changes. Pirfenidone inhibited inflammatory biomarkers release and restored oxidants/antioxidants hemostasis. In a dose-dependent manner, pirfenidone treatment showed a significantly decrease in all of these parameters. In addition, pirfenidone has significantly preserved the histopathological architecture of tissues. Current data demonstrate that Pirfenidone protects against AA-induced UC by modulating the TGF-β1/JNK1 and Caspase-3 pathways. Pirfenidone's antioxidant, anti-inflammatory, and anti-apoptotic properties are thought to be responsible for its therapeutic benefit.

Canagliflozin, an SGLT-2 inhibitor, ameliorates acetic acid-induced colitis in rats through targeting glucose metabolism and inhibiting NOX2

BACKGROUND

Inflammatory bowel disease is defined as chronic noninfectious inflammation of the gastrointestinal tract, including ulcerative colitis and Crohn's disease. Its incidence and predominance have increased globally, with no effective agents for preventing its recurrence or treatment until now.

AIM

The current study aimed to investigate the possible role of canagliflozin (CANA), a sodium-glucose co-transporter-2 inhibitor (SGLT-2), to prevent and treat acetic acid (AA)-induced colitis in a rat model.

METHODS

Colitis was induced in male Wistar rats by intrarectal instillation of 1 ml of 4% (v/v) AA. Rats were treated orally with either CANA (30 mg/kg/day, p.o.) for 10 days before or after colitis induction or sulfasalazine (360 mg/kg/day, p.o.) for 10 days before colitis induction.

RESULTS

AA resulted in a significant increase in disease activity index, colonic weight over length ratio, colon macroscopic damage score, and histological signs of colitis. All of these effects were significantly decreased by CANA administration. Additionally, CANA markedly inhibited AA-induced oxidative stress and inflammatory responses by significantly reducing the up-regulated levels in malondialdehyde, total nitrite, NF-κB, interleukin-1β, and TNF-α, and significantly increasing the down-regulated levels in reduced glutathione, superoxide dismutase, and interleukin-10. CANA significantly inhibited caspase-3 level while rescued survivin expression in colons. Finally, CANA reduced the elevated levels of pyruvic acid and G6PDH activity, as well as the levels of p22phox and NOX2 in the AA-induced colitis.

CONCLUSION

Our findings provide novel evidence that CANA has protective and therapeutic effects against AA-induced colitis by the impact of its antioxidant, anti-inflammatory, and anti-apoptotic effects.

Design, synthesis and molecular modeling studies of novel mesalamine linked coumarin for treatment of inflammatory bowel disease

Inflammatory bowel diseases (IBD) are continuous idiopathic inflammation of GIT. Ulcerative colitis, inflammation of the colonic or rectal mucosa has no known medical cure and its treatment is aimed at reducing the signs and symptoms associated with the disorders, induction and maintenance of remission. In this study, we have reported the synthesis of mesalamine and coumarin linked together by a diazo group. The compound was characterized by various spectroscopic methods. Therapeutic potential of the synthesized compound was investigated through acetic acid induced ulcerative rat model. Pharmacokinetic properties were predicted for the compounds by ADMET related descriptors. Molecular docking studies were conducted with four proteins (COX-2, MMP-9, TNF-α and MPO) to examine the interaction of mesalamine (MS) and mesalamine coumarin derivative (MS-CU). Moreover, molecular dynamic simulations were carried out to study the dynamics and stability of the complexes in solvent system. The binding energy of MS-CU with MPO, COX-2, MMP-9 and TNF-α was found to be -9.5, -10.4, -9.2 and -8.4 kcal/mol respectively. MS-CU exhibited higher binding affinity towards all tested proteins than MS. Molecular dynamic simulation reveals that both MS and MS-CU formed a stable complex with all test proteins in aqueous system. Overall binding energy of MS-CU was more than MS showing stronger affinity towards the test portions. In conclusion, Mesalamine-coumarin derivative reduces colonic damage in acetic acid induced ulcerative colitis in rat model, and therefore may prove to be effective in the management of IBD.

Metabolic activation and colitis pathogenesis is prevented by lymphotoxin β receptor expression in neutrophils

Inflammatory bowel disease is characterized by an exacerbated intestinal immune response, but the critical mechanisms regulating immune activation remain incompletely understood. We previously reported that the TNF-superfamily molecule TNFSF14 (LIGHT) is required for preventing severe disease in mouse models of colitis. In addition, deletion of lymphotoxin beta receptor (LTβR), which binds LIGHT, also led to aggravated colitis pathogenesis. Here, we aimed to determine the cell type(s) requiring LTβR and the mechanism critical for exacerbation of colitis. Specific deletion of LTβR in neutrophils (LTβRΔN), but not in several other cell types, was sufficient to induce aggravated colitis and colonic neutrophil accumulation. Mechanistically, RNA-Seq analysis revealed LIGHT-induced suppression of cellular metabolism, and mitochondrial function, that was dependent on LTβR. Functional studies confirmed increased mitochondrial mass and activity, associated with excessive mitochondrial ROS production and elevated glycolysis at steady-state and during colitis. Targeting these metabolic changes rescued exacerbated disease severity. Our results demonstrate that LIGHT signals to LTβR on neutrophils to suppress metabolic activation and thereby prevents exacerbated immune pathogenesis during colitis.

Reductively modified albumin attenuates DSS-Induced mouse colitis through rebalancing systemic redox state

Albumin (Alb) is the most abundant plasma protein with multiple biological functions, including antioxidative property through its thiol activity. Given that inflammatory bowel disease is associated with a decreased level of Alb and an increased level of Alb oxidation, we asked whether Alb could have a therapeutic effect on colitis. Here we tested this possibility. Bovine serum albumin (BSA) was reductively modified with dithiothreitol (DTT) and administrated via gavage or intraperitoneal injection. Dextran sulfate sodium (DSS)-induced mice colitis was associated with massive oxidative stress, as indicated by the elevated sulfenic acid formation in blood, colon tissues, and feces. Treatment of mice with the reductively modified albumin (r-Alb) attenuated the oxidative stress and reduced local inflammation and tissue injury. These effects of r-Alb were only partially achieved by unmodified Alb and wholly lost after blocking the -SH groups with maleimide. In cultured colon epithelial cells, r-Alb prevented DSS- and H2O2-induced ROS elevation and barrier dysfunction, preceded by inhibition of sulfenic acid formation and P38 activation. Further analysis revealed that Alb was susceptible to H2O2-induced oxidation, and it detoxified H2O2 in a -SH group-dependent way. Moreover, Alb reacted with GSH/GSSG via thiol-disulfide exchange and reciprocally regulated the availability of -SH groups. Collectively, our study shows that r-Alb effectively attenuates DSS colitis via -SH group-mediated antioxidative action. Given that the oxidative stress underlies many life-threatening diseases, r-Alb, functioning as a potent antioxidant, could have a wide range of applications.

Evaluation of the anti-inflammatory and antioxidant effects of the sucralfate in diversion colitis

Sucralfate enemas present good results in the treatment of colitis, however the mechanism of action of the drug is not yet fully clarified.

Objective To evaluate the anti-inflammatory and antioxidant effects of sucralfate enemas in diversion colitis model.

Method Thirty-six Wistar rats underwent intestinal bypass by end colostomy in the descending colon and distal mucous fistula. The animals were divided into 3 experimental groups according to the daily dose of enemas received containing 0.9% SF, sucralfate enemas or sucralfate enemas 1 g/kg/day or 2 g/kg/day. Each group was divided into two subgroups according to euthanasia to be performed 2–4 weeks after derivation. The tissue grade of inflammation was assessed histologically, and neutrophil infiltration by the tissue expression of myeloperoxidase (MPO) identified by immunohistochemistry and quantified by computerized morphometry. Oxidative stress was measured by tissue levels of malondialdehyde (MDA). To compare the results the Student's t test variance was used, and also the variance by ANOVA test, establishing a level of significance of 5% (p < 0.05) for both.

Results The intervention with sucralfate enemas showed improvement in the intensity of tissue inflammation related to the concentration used and the duration of the intervention. Intervention with sucralfate enemas reduced the tissue levels of MPO, independent of concentration or time of intervention (p < 0.01). There was a reduction of MDA levels in animals irrigated with sucralfate enemas, independent of concentration or duration of the intervention (p < 0.01).

Conclusion Enemas with sucralfate enemas reduce inflammation, neutrophil infiltration and oxidative stress in the excluded colon suggesting topical application of the substance to be a valid therapeutic option for the treatment of diversion colitis.

Effects of hydroalcoholic extract of Ziziphus jujuba on acetic acid induced ulcerative colitis in male rat (Rattus norvegicus)

Objective To investigate the effects of hydroalcoholic extract of Ziziphus jujuba on the histopathological, tissue oxidative stress and inflammation plus to antioxidant pathways of colon tissue in rat with induced Ulcerative colitis.

Materials and methods Ulcerative colitis was induced in 80 rats those divided into 8 equal groups. Group 1 and 2 were negative controls receiving 1 mL/day of normal saline in enema and oral; group 3 and 4 as positive control 1 and 2 received 10 mg/kg of intra-colonic asacol and oral mesalazine; groups 5 and 6 received 20% and 40% of hydroalcoholic extract of Z. jujuba trans-rectally; group 7 and 8 received 1500 and 3000 mg/kg of hydroalcoholic extract of Z. jujuba orally, respectively. After 7 days, animals were evaluated for colon tissue histopathology, levels of malondialdehyde and IL-1β, and activities of superoxide dismutase, glutathione peroxidase and myeloperoxidase in colon tissue.

Results Hydroalcoholic extract of Z. jujuba in both forms of trans-rectal and oral administration especially in the higher doses could result into a more healing effect in damaged colonic tissue, more reduce glutathione peroxidase and IL-1β level. Also, these two doses (gel 40% and oral 3000 mg/kg) could more decrease the myeloperoxidase activity and stimulate superoxide dismutase and glutathione peroxidase activities. Also, gel 40% in transrectal administration was more potent than administration 3000 mg/kg in oral.

Conclusion The results of the present study indicated that Z. jujube may be considered as a treatment of choice for Ulcerative colitis especially in gel form and also in dose-dependent pattern.

Evaluation of sucralfate enema in experimental diversion colitis

Diversion colitis (DC) is an inflammatory disease that develops in segments with fecal diversion. Sucralfate (SCF) complex, which consists of sucrose octasulfate and polyaluminum hydroxide, has been demonstrated to be effective in the treatment of different forms of colitis. However, until now, the effects of SCF have not been evaluated in DC.

Objective to evaluate whether the use of enemas containing SFC improves histological findings in experimental DC.

Methods Thirty-six rats underwent right colon bypass procedure through the creation of a proximal colostomy and a distal mucous fistula. The animals were divided into two groups according to the euthanization procedure to be performed two to four weeks after surgery. Each experimental group was divided into three subgroups of six animals, which were submitted to daily application of enemas containing saline solution 0.9% or SCF at concentrations of 1.0 g/kg/day or 2.0 g/kg/day, respectively. The diagnosis of DC in segments with fecal diversion was established by histopathological study considering the following

variables epithelial loss, formation of crypt abscesses, the population of goblet cells, inflammatory infiltrate and presence of fibrosis. For statistical analysis, the nonparametric Mann-Whitney and Kruskal-Wallis tests were used, with a significance level of 5% (p <0.05).

Results It was observed that the daily application of SCF enemas decreased epithelial loss, formation of colon crypt abscesses, inflammatory infiltrate and tissue fibrosis (p <0.05), unrelated to time of intervention. The intervention with SCF preserves the goblet cell population. The effects of the substance on the preservation of colonic epithelium; the decrease in the inflammatory process and subsequent abscess formation in the colon crypts are associated with the concentration used, whereas tissue fibrosis decrease is associated with the concentration and time of intervention.

Conclusion Preventive application of SCF enemas reduces the inflammatory process in the colon with fecal diversion

Effect of escitalopram on an acetic acid-induced ulcerative colitis model

Ulcerative colitis (UC) is a chronic and recurrent gastrointestinal (GI) disorder with an unknown aetiology and pathogenesis. Regarding the effectiveness of antidepressants on UC in animal models of depression and the known anti-inflammatory effects of escitalopram this study was conducted to evaluate the beneficial effects of escitalopram on an acetic acid-induced UC model without depression. UC model was induced by intra rectal (i.r.) administration of 4% acetic acid in rats after 24 hours of fasting. Animals were treated with three doses of escitalopram (5, 10 and 20 mg/kg). Prednisolone (4 mg/kg) was used as a reference drug in UC. Histological and oxidative stress markers were measured in all groups. Results showed significant increase in superoxide dismutase (SOD) activity and glutathione (GSH) levels, as well as significant decrease in myeloperoxidase (MPO) activity, malondialdehyde (MDA) levels, macroscopic factors (ulcer surface area, ulcer severity and weight-to-colon ratio) and microscopic and histological parameters (severity and extent of inflammation, cryptic destruction and severity of tissue involvement) in escitalopram treated rats (10, 20 mg/kg) compared to the UC group. In conclusion, the results of our study are in support of beneficial anti-inflammatory and antioxidant effects of escitalopram in UC.

Changes of Intestinal Oxidative Stress, Inflammation, and Gene Expression in Neonatal Diarrhoea Kids

Diarrhea and disorders in young goats are serious threats to the animals' health, influencing the profitability of the goat industry. There is a need to better understand the potential biomarkers that can reflect the mortality and morbidity in neonatal diarrhea goats. Ten pairs of twin kid goats from the same does (one healthy and the other diagnosed as diarrhea) with the same age under 14 days after birth were used in this study. Since gastrointestinal infection is probably the first ailment in neonatal goats, we aimed to investigate the changes in oxidative stress, inflammation, and gene expression in the gastrointestinal tract of neonatal diarrhea goats based on an epidemiological perspective. The results showed the activity of glutathione peroxidase (GSH-Px) was less (P < 0.05) in the jejunum in neonatal diarrhea goats compared with control goats. However, the malondialdehyde (MDA) activities in the jejunum and ileum were higher (P < 0.05) in neonatal diarrhea goats. There was no significant difference in the super-oxide dismutase (SOD) and catalase (CAT) activity observed between the two groups (P > 0.05). For the concentrations of intestinal interleukin-2 (IL2) and interleukin-6 (IL6), only the IL-2 in ileum of neonatal diarrhea goats was higher than that from healthy control goats. The transcriptomic analysis of the jejunum showed a total of 364 differential expression genes (DEGs) identified in neonatal diarrhea goats compared with control goats. The Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analysis of up-regulated DEGs was mainly related to the ECM–receptor interaction and axon guidance, and the down-regulated DEGs mainly related to the Arachidonic acid metabolism, complement and coagulation cascades, and alpha-Linolenic acid metabolism. Real-time PCR results showed that the expression of most toll-like receptor-4-(TLR4) pathway-related genes and intestinal barrier function-related genes were similar in the two groups. These results suggest that neonatal diarrhea goats experienced a higher intestinal oxidative stress compared with control goats. Thus, it is possible that the antioxidant capacity of young ruminants acts as an indicator of health status and the measurements of oxidation stress may be useful as diagnostic biomarkers, reflecting the mortality and morbidity in neonatal diarrhea goats.

EXPRESSÃO DE E-CADERINA E CLAUDINA-3 NO EPITÉLIO CÓLICO APÓS TERAPIA COM INFLIXIMABE: MODELO EXPERIMENTAL DE COLITE DE EXCLUSÃO

RESUMO - RACIONAL: A etiopatogenia da colite por desuso (DC) ainda não foi totalmente elucidada. As principais teorias consideram que a doença pode estar relacionada ao aumento de bactérias anaeróbias, falta de suprimento de ácidos graxos de cadeia curta (AGCC) e distúrbios imunológicos que se desenvolvem em segmentos colorretais desprovidos de trânsito fecal. OBJETIVO: Verificar se a aplicação de infliximabe modifica o conteúdo tecidual das proteínas E-caderina e claudina-3 no epitélio cólico de ratos sem trânsito intestinal. MÉTODOS: Vinte dois ratos foram submetidos a derivação do trânsito intestinal pelo procedimento de Hartmann. Eles permaneceram com o ostoma por 12 semanas para permitir o desenvolvimento da colite de exclusão. Em seguida, foram divididos em três grupos experimentais: seis animais receberam 2,0 ml de solução salina/semana, oito infliximabe na dose de 5 mg/Kg/semana e, os demais, infliximabe na dose de 10 mg/Kg/semana por 5 semanas consecutivas. Em seguida, os animais foram eutanasiados e os segmentos cólicos com e sem trânsito intestinal foram removidos. A colite por desuso foi diagnosticada pelas alterações histológicas definidas por uma escala previamente validada. Expressão tecidual de E-caderina e claudina-3 foi avaliada por imuno-histoquímica, e o conteúdo tecidual de ambas as proteínas foi quantificado por análise de imagem assistida por computador. RESULTADOS: Segmentos cólicos exclusos de trânsito fecal apresentaram maior grau de inflamação do que os expostos ao trânsito fecal. Inflamação foi menor nos animais tratados com infliximabe, independente da dose utilizada. Níveis de E-caderina e claudina-3 estavam reduzidos no cólon excluso. O tratamento com infliximabe aumentou os níveis das proteínas em segmentos do cólon sem trânsito intestinal, principalmente nos animais que receberam a dose de 10mg/kg/semana. CONCLUSÃO: Infliximabe reduz inflamação nos segmentos do cólon excluso e aumenta o conteúdo tecidual de E-caderina e claudina-3, especialmente na concentração de 10mg/kg/semana.

Tissue-based biosensor for monitoring the antioxidant effect of orally administered drugs in the intestine

For a better understanding of the effect of drugs and their interaction with cells and tissues, there is a need for in vitro and ex vivo model systems which enables studying these events. There are several in vitro methods available to evaluate the antioxidant activity; however, these methods do not factor in the complex in vivo physiology. Here we present an intestinal tissue modified oxygen electrode, used for the detection of the antioxidant effect of orally administered drugs in the presence of H₂O₂. Antioxidants are essential in the defense against oxidative stress, more specifically against reactive oxygen species such as H₂O_2. Due to the presence of native catalase in the intestine, with the tissue-based biosensor we were able to detect H₂O₂ in the range between 50 and 500 µM. The reproducibility of the sensor based on the calculated relative standard deviations was 15 ± 6%. We found that the O₂ production by catalase from H₂O₂ was reduced in the presence of a well-known antioxidant, quinol. This indirectly detected antioxidant activity was also observed in the case of orally administered drugs with a reported anti-inflammatory effect such as mesalazine and paracetamol, while no antioxidant activity was recorded with aspirin and metformin.

Identification of Differential Intestinal Mucosa Transcriptomic Biomarkers for Ulcerative Colitis by Bioinformatics Analysis

Background

Ulcerative colitis (UC) is a complicated disease caused by the interaction between genetic and environmental factors that affect mucosal homeostasis and triggers inappropriate immune response. The purpose of the study was to identify significant biomarkers with potential therapeutic targets and the underlying mechanisms.

Methods

The gene expression profiles of GSE48958, GSE73661, and GSE59071 are from the GEO database. Differentially expressed genes (DEGs) were screened by the GEO2R tool. Next, the Database for Annotation, Visualization and Integrated Discovery (DAVID) was applied to analyze gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. Then, protein-protein interaction (PPI) was visualized by Cytoscape with Search Tool for the Retrieval of Interacting Genes (STRING).

Results

There were a total of 128 common DEGs genes, including 86 upregulated genes enriched in extracellular space, regulation of inflammatory response, chemokine-mediated signaling pathway, response to lipopolysaccharide, and cell proliferation, while 42 downregulated genes enriched in the integral component of the membrane, the integral component of the plasma membrane, apical plasma membrane, symporter activity, and chloride channel activity. The KEGG pathway analysis results demonstrated that DEGs were particularly enriched in cytokine-cytokine receptor interaction, TNF signaling pathway, chemokine signaling pathway, pertussis, and rheumatoid arthritis. 18 central modules of the PPI networks were selected with Cytotype MCODE. Furthermore, 18 genes were found to significantly enrich in the extracellular space, inflammatory response, chemokine-mediated signaling pathway, TNF signaling pathway, regulation of cell proliferation, and immune response via reanalysis of DAVID.

Conclusion

The study identified DEGs, key target genes, functional pathways, and pathway analysis of UC, which may provide potential molecular targets and diagnostic biomarkers for UC.

A systematic review of preclinical studies on the efficacy of propolis for the treatment of inflammatory bowel disease

Propolis is a resinous substance produced by bees from plants. There has been some evidence indicating that propolis may be a candidate for the treatment of inflammatory bowel disease (IBD) because of its potent antioxidant properties and ability to modulate immune response and gut microbiome. The objective of this systematic review was to investigate the role of propolis in the treatment of IBD, emphasizing possible mechanisms underlying the anti-inflammatory properties of it. Searches were performed in ISI, PubMed/Medline, Scopus, EMBASE, and Cochrane Library databases up to March 2020. According to the studies examined in this review, the administration of propolis can be useful in attenuating many aspects of clinical, macroscopic, and histological features of colitis in animal models. The efficacy of propolis in the treatment of IBD might be attributed to its potent antioxidants and anti-inflammatory activities. Propolis may also be involved in the modulation of the gut microbiota and in the improvement of the intestinal mucosal barrier function. The major mechanism of action is most likely to be mediated via the prevention of some transcriptional factors and associated proteins. However, future studies are warranted to investigate the clinical utility of propolis as a candidate in the treatment of IBD.

The protective effect of Lactobacillus versus 5-aminosalicylic acid in ulcerative colitis model by modulation of gut microbiota and Nrf2/Ho-1 pathway

AIMS

Ulcerative colitis (UC) has many complications, from colonic damage to colorectal cancer. The mystery of both etiology and effective treatment of UC still challenging process. The role of gut microbiota in UC is still unclear. In the current study we compare the difference in gut microbiota abundance in both UC and normal colon besides the therapeutic effect of Lactobacillus spp. in treating UC versus the standard drug.

MATERIALS AND METHODS

The experimental panel included five group of rats; normal control, UC diseased rats, sterilizing rats, ASA treated and Lactobacillus treated. The change in the microbiota abundance was investigated using conventional and real time PCR. In parallel, clinical evaluation of UC and macroscopic examination scoring was also done. Colonic oxidants/antioxidant stress biomarkers; MDA, GSH, catalase, myeloperoxidase activity, and SOD activity were assessed. Colon Nrf2, HO-1 contents and TNF-α was evaluated.

KEY FINDINGS

The current study revealed a significant difference in the relative abundance of microbiota where, UC is associated with massive increase of E. coli and Fusobacterium spp., while enormous decrease in Bifidobacteria spp. in contrast with negative control. Both 5-ASA and Lactobacillus show a significant amelioration of all antioxidant enzymes and marked decline of inflammatory and oxidative stress markers. Both Lactobacillus and 5-ASA show significant increase of NrF2 and HO-1 and marked decrease of TNF-α.

SIGNIFICANCE

Lactobacillus spp. exerted a beneficial effect on the inflammation, oxidative stress and the symbiosis of gut microbiota that improve structural intestinal defect and promote healing in UC.

The Close Interplay of Nitro-Oxidative Stress, Advanced Glycation end Products and Inflammation in Inflammatory Bowel Diseases

BACKGROUND

Inflammatory Bowel Disease (IBD) exhibits no defined aetiology. However, factors such as genetic and nitro-oxidative stress are associated with chronic inflammation and IBD progression to Colorectal Cancer (CRC). The present review discusses the association of nitro-oxidative stress, inflammation and Advanced Glycation End products (AGE) and their corresponding receptor (RAGE) in IBD and examines the connection between these factors and nuclear factors, such as Nuclear Factor Kappa B (NF-κB), factorerythroid 2-related factor-2 (Nrf2), and p53 Mutant (p53M).

METHODS

We searched the PubMed, ScienceDirect and Web of Science databases using a combination of the following terms: IBD, CRC, oxidative stress, inflammation, NF-κB, Nrf2, p53M, AGE and RAGE.

RESULTS

Oxidative stress and inflammation activated two cellular pathways, the nuclear expression of pro-inflammatory, pro-oxidant and pro-oncogenic genes based on NF-κB and p53M, which is associated with NF-κB activation, Deoxyribonucleic acid (DNA) damage and the expression of pro-oncogenic genes. Nrf2 stimulates the nuclear expression of enzymatic and non-enzymatic antioxidant systems and anti-inflammatory genes, and is inhibited by chronic oxidative stress, NF-κB and p53M. AGE/RAGE are involved in inflammation progression because RAGE polymorphisms and increased RAGE levels are found in IBD patients. Alterations of these pathways in combination with oxidative damage are responsible for IBD symptoms and the progression to CRC.

CONCLUSION

IBD is an inflammatory and nitro-oxidative stress-based bowel disease. Achieving a molecular understanding of the biochemical events and their complicated interactions will impact basic and applied research, animal models, and clinical trials.

Effects of Aqueous and Methanolic Extracts of Stem Bark of Alstonia boonei De Wild. (Apocynaceae) on Dextran Sodium Sulfate-Induced Ulcerative Colitis in Wistar Rats

Among the most exploited species in Cameroon, Alstonia boonei is widely used in African medicine for the relief of several pathologies including gastrointestinal disorders. This study was conducted in order to assess the effects of aqueous and methanol stem-bark extracts of Alstonia boonei on DSS- (dextran sodium sulfate-) induced intestinal colitis and to determine its antioxidant potential. The classes of secondary metabolites present in these extracts were determined by chemical screening. The production of TNF-α, IL-6, IL-1β, and PGE2 was performed by in vitro ELISA analysis. Anticolitis effects were determined using an in vivo model of ulcerative colitis induced by DSS. The colitis was induced with a double dose of DSS (3% and 1%), and the aqueous and methanol extracts were administered orally from the 6^th day after commencement of induction. The phytochemical screening revealed the presence of six classes of secondary metabolites in these crude extracts: tannins, saponins, alkaloids, steroids, flavonoids, and phenols. Methanol and aqueous extracts of Alstonia boonei significantly (P < 0.001) inhibited TNF-α, IL-6, IL-1β, and PGE2 production stimulated by LPS. Both extracts at all doses significantly reduced (P < 0.01, P < 0.001) the signs of DSS-induced colitis in the Wistar rats by decreasing inflammation and chronic colon damage. In addition, the extracts significantly (P < 0.001) reduced malondialdehyde and nitric oxide levels in the colon and significantly (P < 0.01) increased superoxide dismutase and catalase and reduced glutathione (P < 0.05). Both extracts showed greater activity than the reference substance (prednisolone 4 mg/kg) used in this study. This study has demonstrated that aqueous and methanol extracts of Alstonia boonei stem bark have healing properties against colitis experimentally induced by DSS in rats.

Molecules from American Ginseng Suppress Colitis through Nuclear Factor Erythroid-2-Related Factor 2

Ulcerative colitis (UC) is a chronic inflammatory bowel disease that affects millions of people worldwide and increases the risk of colorectal cancer (CRC) development. We have previously shown that American ginseng (AG) can treat colitis and prevent colon cancer in mice. We further fractionated AG and identified the most potent fraction, hexane fraction (HAG), and the most potent compound in this fraction, panaxynol (PA). Because (1) oxidative stress plays a significant role in the pathogenesis of colitis and associated CRC and (2) nuclear factor erythroid-2-related factor 2 (Nrf2) is the master regulator of antioxidant responses, we examined the role of Nrf2 as a mechanism by which AG suppresses colitis. Through a series of in vitro and in vivo Nrf2 knockout mouse experiments, we found that AG and its components activate the Nrf2 pathway and decrease the oxidative stress in macrophages (mΦ) and colon epithelial cells in vitro. Consistent with these in vitro results, the Nrf2 pathway is activated by AG and its components in vivo, and Nrf2^-/- mice are resistant to the suppressive effects of AG, HAG and PA on colitis. Results from this study establish Nrf2 as a mediator of AG and its components in the treatment of colitis.

Therapeutic effects of vitamin D on acetic acid-induced colitis in rats

PURPOSE

To analyze the effect of calcitriol treatment on acute colitis in an experimental rat model.

METHODS

A total of 24 adult Sprague Dawley albino rats were randomly separated into 3 equal groups: control group (n:8), colitis group (n:8), calcitriol administered group (n:8). A single dose of acetic acid (1 ml of 4% solution) was administered intrarectally to induce colitis. Group 1 was given 1 ml/kg 0.9% NaCl intraperitoneally; rats belonging to Group 2 were administered calcitriol 1 µg/kg for 5 days.

RESULTS

Plasma tumor necrosis factor alpha, Pentraxin 3, and malondialdehyde levels were significantly lower in the calcitriol administered colitis group than in the standard colitis group (p<0.01). In the Calcitriol group, there was a significant histological improvement in hyperemia, hemorrhage and necrotic areas in the epithelium compared to the placebo group (p <0.000).

CONCLUSION

The findings suggest that calcitriol may be an agent that could be used in acute colitis treatment.

Hydrogen peroxide and disease: towards a unified system of pathogenesis and therapeutics

Although the immune response has a prominent role in the pathophysiology of ulcerative colitis, sepsis, and systemic lupus erythematosus, a primary immune causation has not been established to explain the pathogenesis of these diseases. However, studies have reported significantly elevated levels of colonic epithelial hydrogen peroxide (a known colitic agent) in ulcerative colitis prior to the appearance of colitis. And patients with sepsis are reported to have toxic levels of blood hydrogen peroxide, whose pathologic effects mirror the laboratory and clinical abnormalities observed in sepsis. More recently, evidence supports a causal role for cellular hydrogen peroxide (a potent apoptotic agent) in the enhanced apoptosis believed to be the driving force behind auto-antigenic exposure and chronic immune activation in systemic lupus erythematosus. The different biological properties of hydrogen peroxide exert distinct pathologic effects depending on the site of accumulation within the body resulting in a unique disease patho-phenotype. On a cellular level, the build-up of hydrogen peroxide triggers apoptosis resulting in systemic lupus erythematosus, on a tissue level (colonic epithelium) excess hydrogen peroxide leads to inflammation and ulcerative colitis, and on a systemic level the pathologic effects of toxic concentrations of blood hydrogen peroxide result in bioenergetic failure and microangiopathic dysfunction leading to multiple organ failure and circulatory shock, characteristic of advanced sepsis. The aim of this paper is to provide a unified evidence-based common causal role for hydrogen peroxide in the pathogenesis of ulcerative colitis, sepsis, and systemic lupus erythematosus. Based on this new theory of pathogenesis, a novel evidence-based treatment of sepsis is also discussed.

Increased levels of 5',8-Cyclopurine DNA lesions in inflammatory bowel diseases

Chronic inflammation is estimated to be a causative factor in a variety of diseases. Under inflammatory conditions reactive oxygen species (ROS) and nitrogen species (RNS) are released leading to DNA damage accumulation and genomic instability. Purine 5′,8-cyclo-2′-deoxynucleosides (cPu) are oxidative DNA lesions, exclusively derived from the attack of HO^• radicals, which are known to have cytotoxic and mutagenic properties. Herein, we have analyzed the presence of cPu in genomic DNA isolated from fresh colon and visceral adipose tissue biopsies collected from inflammatory bowel diseases (IBD)-affected patients and severely obese subjects, respectively, versus what observed in the control specimens. In colon biopsies, characterized by a higher gene expression level of inducible nitric oxide synthase (iNOS), a significant increase of 8-oxo-7,8-dihydro-2′-deoxyadenosine (8-oxo-dA) and 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxo-dG) lesions and an accumulation of both diastereomeric cPu have been detected. In contrast, the 8-oxo-dA and 8-oxo-dG levels were extremely lower compared to the colon tissues values and no accumulation of cPu, in the inflamed visceral adipose tissue biopsies isolated from bariatric patients versus the lean counterpart was reported. In addition, in adipose tissue undetectable levels of iNOS have been found. These data suggest a potential involvement of cPu in the colon cancer susceptibility observed in IBD patients.

Protective effect of ShaoYao decoction on colitis-associated colorectal cancer by inducing Nrf2 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Ulcerative colitis were prone to develop into ulcerrelated colorectal cancer with high risk of mortality. Shaoyao Decoction (SYD), a compound prescription of Chinese traditional medicine, was reported to have anti-colorectal cancer effect. Thus this study mainly investigated the protective and preventive effect of SYD against oxidative damages and inflamatory response through in vivo and in vitro experiments.

AIM OF THE STUDY

Shaoyao decoction (SYD), a compound prescription of traditional Chinese medicine, is effective in treating ulcerative colitis. The increased levels of reactive oxygen species (ROS) in inflammatory cells potentially drive the development of carcinomas. Nuclear factor-erythroid 2-related factor 2 (Nrf2) has became a novel target for the prevention of colorectal cancer (CRC). In this study, we assessed the antioxidation effect of SYD against colitis associated colorectal cancer through in vivo and in vitro experiments.

MATERIALS AND METHODS

In vivo AOM/DSS-induced murine model of colon cancer and in vitro H₂O₂-induced oxidative stress in HT-29 cells model were conducted. To determine the antioxidant activity of SYD, protein expression of Nrf2 and its downstream genes were detected by western blot, RT-PCR and Enzyme-linked immunosorbent assay.

RESULTS

Both in vivo and in vitro experiments demonstrated that SYD exerts antioxidant effect through activation of Nrf2 pathway and upregulation expression of Nrf2 downstream genes. SYD is shown to have preventive effect against colitis-associated colorectal cancer.

CONCLUSIONS

These observations suggest that SYD is effective in the enhancement of antioxidant ability via activation of Nrf2 pathway and the up-regulation of Nrf2-downstream phase II enzymes expression. The anti-inflammation and antioxidant action of SYD together contributes to the prevention and treatment of ulcerrelated colorectal cancer.

Dynamic bioenergetic alterations in colorectal adenomatous polyps and adenocarcinomas

BACKGROUND

Energy metabolism in carcinogenesis is poorly understood. It is widely accepted the majority of colorectal cancers (CRCs) arise from adenomatous polyps (APs). We aimed to characterize the bioenergetic alterations in APs and CRCs.

METHODS

Fifty-six APs, 93 CRCs and adjacent normal mucosae were tested. Oxygen consumption rate (OCR) was measured representing mitochondrial oxidative phosphorylation (OxPhos), and extracellular acidification rate (ECAR)was measured representing glycolysis. Mitochondrial DNA (mtDNA) variants and mutations were studied. Over-expressed metabolic genes in APs were identified by microarray and validated by qRT-PCR, Western blots and immunohistochemistry. Identified genes were knocked down in WiDr and colo205 CRC cell lines, and their expression was analyzed in APs/CRCs with enhanced glycolysis.

FINDINGS

ECAR, not OCR, was significantly increased in APs. While no difference of ECAR was found between CRCs and normal mucosae, OCR was significantly reduced in CRCs. OCR/ECAR ratio was decreased in APs over 1 cm, APs with a villous component and CRCs, indicating their glycolytic tendencies. The number of mtDNA mutations was increased in APs and CRCs, but not correlated with metabolic profiles. Two metabolic genes ALDOB and SLC16A4 were up-regulated in APs. Both ALDOB-knockdown and SLC16A4-knockdown CRC cell lines showed increased basal motichondrial OxPhos and decreased basal glycolysis. Moreover, the increase of mitochondrial ATP-linked respiration and the decrease of glycolytic capacity were showed in SLC16A4-knockdown cells. Finally, APs/CRCs with enhanced glycolysis had increased SLC16A4 expression.

INTERPRETATION

ATP production shifts from OxPhos to glycolysis in the process of AP enlargement and villous transformation. OxPhos defects are present in CRCs but not in APs. APs and CRCs tend to accumulate mtDNA mutations, but these are not correlated with bioenergetic profiles. Finally, the ALDOB and SLC16A4 may contribute to the glycolytic shift in APs/CRCs.

Redox modulatory protective effects of ω-3 fatty acids rich fish oil against experimental colitis

Ulcerative colitis (UC), a form of inflammatory bowel disease (IBD), is an immune-modulated disorder characterized by chronic and recurring inflammatory episodes. Oxidative stress and COX pathway of prostaglandin (PG) biosynthesis are indispensable to pathogenesis of UC. Any imbalance between PGs can compromise the mucosal homeostasis, leading to mucosal damage and chronic inflammation. However, blocking these PGs using classical Cox inhibitors such as non-steroidal anti-inflammatory drugs (NSAIDs) can instead aggravate signs of IBD. Therefore, realizing the need for safer and well tolerable alterative treatment approaches, currently, we evaluated the efficacy of n-3 fatty acids rich fish oil (FO) in the resolution of UC. Using a dextran sodium sulfate (DSS) model of experimental colitis, we have demonstrated that supplementation of FO containing 180 mg EPA and 120 mg DHA for 1 month relieved the signs (diarrhea, bloody stools, weight loss) of colitis-associated inflammation. To understand the biophysical changes associated with FO mediated inflammatory regulation, impedance measurement and Fourier transform infrared spectroscopy (FTIR) were done. These changes were also correlated with oxidative stress through markers such as GST, glutathione peroxidase (GPx), LPO, catalase, protein carbonyl content, GR, etc. in colonic mucosa. The modulation of COX mediated pathways in UC-associated inflammation was observed by protein expressions of various pro-inflammatory cytokines such as TNF-α and enzymes of PG synthesis such as COX-2, PGES, TXAS, and anti-inflammatory PGDS. Refuting the earlier reports that suggested the contradictory effects of FO, in the current study, we evidently demonstrated that the protective effects of FO are mediated through molecular mechanisms involving the redox-regulation of metabolism of key lipid metabolites.

Enemas with mesalazine increase the tissue contents of mucins in the colonic mucosa devoid of fecal stream

Purpose:

To evaluate the inflammatory reaction and measure the content of mucins, in the colonic mucosa without fecal stream submit to intervention with mesalazine.

Methods:

Twenty-four rats were submitted to a left colostomy and a distal mucous fistula and divided into two groups according to euthanasia to be performed two or four weeks. Each group was divided into two subgroups according daily application of enemas containing saline or mesalazine at 1.0 g/kg/day. Colitis was diagnosed by histological analysis and the inflammatory reaction by validated score. Acidic mucins and neutral mucins were determined with the alcian-blue and periodic acid of Schiff techniques, respectively. Sulfomucin and sialomucin were identified by high iron diamine-alcian blue technique. The tissue contents of mucins were quantified by computer-assisted image analysis. Mann-Whitney test was used to analyze the results establishing the level of significance of 5%.

Results:

Enemas with mesalazine in colonic segments without fecal stream decreased the inflammation score and increased the tissue content of all subtypes of mucins. The increase of tissue content of neutral, acid and sulfomucin was related to the time of intervention.

Conclusion:

Mesalazine enemas reduce the inflammatory process and preserve the content of mucins in colonic mucosa devoid of fecal stream.

Efficacy of Pyrus elaeagnifolia subsp. elaeagnifolia in acetic acid–induced colitis model

In Turkish folk medicine, the fruits of Pyrus elaeagnifolia subsp. elaeagnifolia have been used to treat diarrhea and detoxify poisonous snake bites by enlarging the wound. The aim of the study was to confirm the ethnopharmacological usage of the plant using in vivo and in vitro models. Experimental colitis was performed under anesthesia by intrarectal administration of acetic acid in rats, and the extracts were administered orally. The colonic malondialdehyde (MDA), tumor necrosis factor (TNF-α), interleukin-6 (IL-6), and nitrite levels, in addition to the myeloperoxidase (MPO) and caspase-3 activities, were measured to determine the effects of the plant extracts. The methanol (MeOH) extract revealed a significant decrease in MPO and caspase-3 levels. The MeOH extract was found to have the highest total tannin content. It was also found to have significant antioxidant (p ˂ 0.01) and anti-inflammatory activities (p ˂ 0.05) in acetic acid induced colitis rat model . According to our results, the present study exhibited a decrease in MDA, nitrite, IL-6, and TNF-α levels in the colon tissue and blood in the MeOH extract treated group. The findings of this study can help in treating various disorders, such as Clostridium difficile infection, irritable bowel syndrome, and inflammatory bowel diseases.

Vinpocetine Ameliorates Acetic Acid-Induced Colitis by Inhibiting NF-κB Activation in Mice

The idiopathic inflammatory bowel diseases (IBD) comprise two types of chronic intestinal disorders: Crohn's disease and ulcerative colitis. Recruited neutrophils and macrophages contribute to intestinal tissue damage via production of ROS and NF-κB-dependent pro-inflammatory cytokines. The introduction of anti-TNF-α therapies in the treatment of IBD patients was a seminal advance. This therapy is often limited by a loss of efficacy due to the development of adaptive immune response, underscoring the need for novel therapies targeting similar pathways. Vinpocetine is a nootropic drug and in addition to its antioxidant effect, it is known to have anti-inflammatory and analgesic properties, partly by inhibition of NF-κB and downstream cytokines. Therefore, the present study evaluated the effect of the vinpocetine in a model of acid acetic-induced colitis in mice. Treatment with vinpocetine reduced edema, MPO activity, microscopic score and macroscopic damage, and visceral mechanical hyperalgesia. Vinpocetine prevented the reduction of colonic levels of GSH, ABTS radical scavenging ability, and normalized levels of anti-inflammatory cytokine IL-10. Moreover, vinpocetine reduced NF-κB activation and thereby NF-κB-dependent pro-inflammatory cytokines IL-1β, TNF-α, and IL-33 in the colon. Thus, we demonstrate for the first time that vinpocetine has anti-inflammatory, antioxidant, and analgesic effects in a model of acid acetic-induced colitis in mice and deserves further screening to address its suitability as an approach for the treatment of IBD.

The Plasma Membrane: A Platform for Intra- and Intercellular Redox Signaling

Membranes are of outmost importance to allow for specific signal transduction due to their ability to localize, amplify, and direct signals. However, due to the double-edged nature of reactive oxygen species (ROS)—toxic at high concentrations but essential signal molecules—subcellular localization of ROS-producing systems to the plasma membrane has been traditionally regarded as a protective strategy to defend cells from unwanted side-effects. Nevertheless, specialized regions, such as lipid rafts and caveolae, house and regulate the activated/inhibited states of important ROS-producing systems and concentrate redox targets, demonstrating that plasma membrane functions may go beyond acting as a securing lipid barrier. This is nicely evinced by nicotinamide adenine dinucleotide phosphate (NADPH)-oxidases (NOX), enzymes whose primary function is to generate ROS and which have been shown to reside in specific lipid compartments. In addition, membrane-inserted bidirectional H₂O₂-transporters modulate their conductance precisely during the passage of the molecules through the lipid bilayer, ensuring time-scaled delivery of the signal. This review aims to summarize current evidence supporting the role of the plasma membrane as an organizing center that serves as a platform for redox signal transmission, particularly NOX-driven, providing specificity at the same time that limits undesirable oxidative damage in case of malfunction. As an example of malfunction, we explore several pathological situations in which an inflammatory component is present, such as inflammatory bowel disease and neurodegenerative disorders, to illustrate how dysregulation of plasma-membrane-localized redox signaling impacts normal cell physiology.

Sophora flavescens Containing-QYJD Formula Activates Nrf2 Anti-Oxidant Response, Blocks Cellular Transformation and Protects Against DSS-Induced Colitis in Mouse Model

Qu-Yu-Jie-Du decoction (QYJD) is a commercially available traditional Chinese medicine (TCM). It is an aqueous extract of a Chinese herbal formula primarily consisting of eight TCM herbs: Taraxacum campylodes G.E. Haglund, Coix lacryma-jobi L., Smilax glabra Roxb., Sanguisorba officinalis L, Styphnolobium japonicum (L.) Schott, Prunus persica (L.) Batsch, Sophora flavescens Aiton, and Eupolyphaga sinensis Walker. Matrine and oxymatrine are two of the major phytochemical constituents of QYJD. Inflammation and oxidative stress are strongly associated with colon carcinogenesis. Colorectal cancer (CRC) is the third most common type of cancer. Therefore, cancer chemopreventive agents targeting CRC are urgently needed. This study was conducted to investigate the potential anticancer effects and the underlying mechanisms of QYJD and its active constituents, matrine and oxymatrine, in human colon cancer HT29 cells and in a dextran sulfate sodium (DSS)-induced colitis mouse model. QYJD and matrine effectively inhibited the proliferation and anchorage-independent growth of HT29 cells in a dose-dependent manner. QYJD and matrine also induced an Nrf2-mediated anti-oxidant response element-luciferase activity and upregulated the Nrf2-mediated anti-oxidative stress genes HO-1 and NQO1 at both the mRNA and protein levels. In the DSS-induced colitis mouse model, QYJD reduced the disease activity index (DAI) and alleviated colonic shortening. Elevated Nrf2 and HO-1 mRNA levels were also observed in QYJD-treated mice. These findings showed that QYJD could elicit anti-inflammatory and anti-oxidative stress response in vitro in a cell line and in vivo in a DSS-induced colitis mouse model. These responses may contribute to the overall anticolon cancer effect of QYJD.

EVALUATION OF ENEMAS CONTAINING SUCRALFATE IN TISSUE CONTENT OF MUC-2 PROTEIN IN EXPERIMENTAL MODEL OF DIVERSION COLITIS

BACKGROUND

The effects of topical application of sucralfate (SCF) on the tissue content of MUC-2 protein have not yet been evaluated in experimental models of diversion colitis.

AIM

To measure the tissue content of MUC-2 protein in the colonic mucosa diverted from fecal stream submitted to the SCF intervention.

METHODS

Thirty-six rats underwent derivation of intestinal transit through proximal colostomy and distal mucous fistula. The animals were divided into three groups which were submitted application of enemas with saline, SCF 1 g/kg/day and SCF 2 g/kg/day. Each group was divided into two subgroups, according to euthanasia was done after two or four weeks. The colitis diagnosis was established by histopathological study and the inflammatory intensity was evaluated by previously validated scale. The MUC-2 protein was identified by immunohistochemistry and the tissue content was measured computerized morphometry).

RESULTS

The application of enemas with SCF in the concentration of 2 g/kg/day reduced inflammatory score of the segments that were diverted from fecal stream. The content of MUC-2 in diverted colon of the animals submitted to the intervention with SCF, independently of intervention period and the used concentration, was significantly greater than animals submitted to the application of enemas containing saline (p< 0.01). The content of MUC-2 after the intervention with SCF in the concentration of 2 g/kg/day was significantly higher when compared to the animals submitted to the application containing SCF at concentration of 1.0 g/kg/day (p<0.01). The tissue content of MUC-2 reached the highest values after intervention with SCF in the concentration of 2 g/kg/day for four weeks (p<0.01).

CONCLUSION

The preventive application of enemas containing SCF reduces the inflammatory score and avoids the reduction of tissue content of MUC-2, suggesting that the substance is a valid therapeutic strategy to preserve the mucus layer that covers the intestinal epithelium.

Resolution of Cox mediated inflammation by Se supplementation in mouse experimental model of colitis

UC a form of IBD is a chronic inflammatory disorder of large intestine, with unknown etiology. Reports suggest a critical role of COX-2 dependent prostaglandins (PGs) mediated inflammatory pathway in pathophysiology of UC. However, COX inhibition using NSAIDs exacerbate IBD and thus is not a viable solution. Currently, in DSS induced experimental colitis in mice, we have demonstrated that dietary Se supplementation (0.5ppm as sodium selenite) symptomatically resolves the signs of inflammation in a redox sensitive manner as compared to Se deficient (0.01ppm) conditions, as seen by modulation in oxidative stress markers, morphological changes, histopathological examinations, biochemical studies such as MPO activity, activity of intestinal markers enzymes as well as mRNA and expressions of various pro and anti-inflammatory factors such as, mPGES, hPGDS, TXAS, 15-PGDH, GPX-1 and GPX-2. These findings were validated and correlated with changes in the biophysical parameters such as membrane fluidity, electrical parameters (impedance), transport across the colonic tissue and FTIR. Current study not only concluded that Se at supranutritional concentrations by modulating the redox status relieves the signs of colitis by regulating COX dependent PG biosynthetic pathway, but also sheds light on the biophysical characterization of these inflammatory/resolution pathways involved in UC.

INCREASED OXIDATIVE STRESS IN THE BLOOD OF OSTOMY PATIENTS

BACKGROUND

Ostomy is a surgical procedure that creates a stoma that aims to construct a new path for the output of feces or urine. The relationship of oxidative stress (OxS) markers in patients with ostomy is still poorly described.

OBJECTIVE

The present study was aimed at investigating the changes in oxidative stress parameters in peripheral blood collected from ostomy patients when compared with a healthy control group.

METHODS

It was evaluated 29 ostomy patients and 30 healthy control patients. The oxidative stress parameters evaluated were: lipid peroxidation [lipid hydroperoxide (LPO), 8-isoprostane (8-ISO) and 4-hydroxynonenal (4-HNE)], protein oxidation and nitration [carbonyl and 3-nitrotyrosine (3-NT)] and DNA oxidation [8-hydroxy-2'-deoxyguanosine (8-OHDG)] in serum from ostomy patients compared to health controls.

RESULTS

The data showed an increase of LPO, 8-ISO, 4-HNE, 3-NT and 8-OHDG in serum collected from ostomy patients when compared to healthy controls.

CONCLUSION

The findings support the hypothesis that ostomy triggers the oxidative stress observed in the blood collected from these patients.