Rat Model Of Colitis Research Articles

Cilostazol protects against acetic acid-induced colitis in rats: Possible role for cAMP/SIRT1 pathway

The phosphodiesterase-3 inhibitor, cilostazol has been recently shown to protect against chemically induced colitis in animal models. However, whether cyclic adenosine monophosphate (cAMP) contributes to the anti-inflammatory activity of cilostazol in colitis is still unknown. In the current study, we investigated the role of cAMP/silent information regulator-1 (SIRT-1) pathway in the protective effect of cilostazol using rat model of acetic acid-induced colitis. Upregulation of SIRT1 activity and expression has been recently shown to protect against chemically induced colitis. Our results demonstrated that cilostazol alleviated the histopathological changes associated with acetic acid-induced colitis. Interestingly, pre-administration of cilostazol increased cAMP concentration and SIRT1 expression in colonic mucosa to levels similar to that observed in control animals without induction of colitis. In addition, cilostazol inhibited the SIRT1 targets; NF-κB, Akt and MAPK inflammatory pathways as demonstrated by suppression of acetic acid-induced upregulation of NF-κB activity, p-AKT levels and the expression of p38 MAPK. NF-κB activity and the levels of p-AKT, tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β) were similar in rats pretreated with cilostazol prior to induction of colitis and the control rats without colitis. Furthermore, cilostazol reduced acetic acid-induced oxidative stress and apoptosis. In conclusion, the protective effect of cilostazol against acetic acid-induced colitis may be attributed to activation of SIRT1 expression by cAMP. SIRT1 is suggested to contribute to cilostazol-induced suppression of NF-κB, Akt and MAPK inflammatory pathways, oxidative stress and apoptosis.

M2 Macrophages and Phenotypic Modulation of Intestinal Smooth Muscle Cells Characterize Inflammatory Stricture Formation in Rats

The progression of Crohn disease to intestinal stricture formation is poorly controlled, and the pathogenesis is unclear, although increased smooth muscle mass is present. A previously described rat model of trinitrobenzenesulfonic acid-induced colitis is re-examined here. Although inflammation of the mid-descending colon typically resolved, a subset showed characteristic stricturing by day 16, with an inflammatory infiltrate in the neuromuscular layers including eosinophils, CD3-positive T cells, and CD68-positive macrophages. Closer study identified CD163-positive, CD206-positive, and arginase-positive cells, indicating a M2 macrophage phenotype. Stricturing involved ongoing proliferation of intestinal smooth muscle cells (ISMC) with expression of platelet-derived growth factor receptor beta and progressive loss of phenotypic markers, and stable expression of hypoxia inducible factor 1 subunit alpha. In parallel, collagen I and III showed a selective and progressive increase over time. A culture model of the stricture phenotype of ISMC showed stable hypoxia inducible factor 1 subunit alpha expression that promoted growth and improved both survival and growth in models of experimental ischemia. This phenotype was hyperproliferative to serum and platelet-derived growth factor BB, and unresponsive to transforming growth factor beta, a prominent cytokine of M2 macrophages, compared with control ISMC. We identified a hyperplastic phenotype of ISMC, uniquely adapted to an ischemic environment to drive smooth muscle layer expansion, which may reveal new targets for treating intestinal fibrosis.

Ginsenoside Rd therapy improves histological and functional recovery in a rat model of inflammatory bowel disease.

Ginsenoside Rd (GRd) is a biologically active component of ginseng that stimulates the proliferation of endogenous stem cells. The objective of our research was to evaluate the utility of GRd in gastrointestinal mucosal regeneration in a rat model of inflammatory bowel disease (IBD) and to clarify whether GRd exerts its pharmacological effects by modulating endogenous intestinal stem cells. The IBD rat model was established via subcutaneous injection of indomethacin, and 10, 20, or 40 mg/kg GRd or an equal volume of physiological saline was then administered orally to rats in different groups every day for seven consecutive days. We observed that GRd treatment, especially 20 mg/kg GRd, significantly reduced indomethacin-induced damage compared with that in the control group. By measuring the mRNA and protein levels of the intestinal stem cell markers Bmi and Msi-1 and the intestinal epithelial cell marker CDX-2 as well as by double-labelling these markers with 5-bromo-2-deoxyuridine (BrdU), we inferred that GRd could stimulate the proliferation and differentiation of endogenous intestinal stem cells in IBD model rats, leading to improved recovery of intestinal function.

Celastrol augments sensitivity of NLRP3 to CP-456773 by modulating HSP-90 and inducing autophagy in dextran sodium sulphate-induced colitis in rats

NLRP3, one of the HSP-90 clients, has been defined as a critical component of IBD. In a rat model of DSS-induced colitis, we investigated the anti-inflammatory potential of the combined therapy with CP-456773 (CP), an NLRP3 inhibitor, and celastrol (CSR), an NF-κB inhibitor. Our results revealed that the CSR/CP combined therapy (CCCT) attenuated colon shortening, DAI and MDI in addition to improvement of the colonic histological picture. Moreover, the CCCT increased the antioxidant defense machinery of the colonic tissue and decreased MPO activity. Furthermore, the inflammation markers such as TNF-α and IL-6 were downregulated. These effects might be attributed to the inhibitory effect of CSR on the priming step of the NLRP3 inflammasome activation by interrupting NF-κB signalling and inhibition of HSP-90 (at the protein and mRNA levels) along with inhibitory effect of CP on the expression of the NLRP3. These latter effects resulted in decreased tissue expression and activity of the caspase-1 and repressing the subsequent release of the active forms of IL-1β and IL-18, hence, the pyroptosis process is restrained. Additionally, the CCCT resulted in inducing autophagy by AMPK/mTOR-dependent mechanisms leading to the accumulation of BECN1 protein and a significant decrease in the levels of p62 SQSTM1. The inhibitory effect on HSP-90 in conjunction with induction of autophagy suggest increased autophagic degradation of NLRP3. This novel approach provides a basis for the clinical application of this combination in IBD treatment and might also be promising for the pharmacological intervention of other NLRP3 inflammasome-dependent inflammatory conditions.

The JAK2 inhibitor AG490 regulates the Treg/Th17 balance and alleviates DSS-induced intestinal damage in IBD rats.

The pathogenesis of inflammatory bowel disease (IBD) remains unclear, and it is currently believed that an imbalance in regulatory T (Treg) cells/T helper 17 cells (Th17 cells) is related to the occurrence and development of IBD. Recently, the JAK2 inhibitor AG490 has been used in animal models such as rheumatoid arthritis and bronchial asthma models and shown to exert immunoregulatory functions that improve disorder in the Treg/Th17 cell balance. This study aimed to evaluate the effect of AG490 on the intestinal inflammatory process in an IBD rat model. A dextran sulfate sodium (DSS)-induced IBD rat model was established, and disease activity index (DAI) scores were calculated. The histopathological damage score was determined by haematoxylin-eosin (H&E) staining. Treg/Th17 cells in the spleen were detected by flow cytometry. The levels of interleukin (IL)-10, IL-6 and IL-17A were detected by enzyme-linked immunosorbent assay (ELISA). AG490 attenuated DSS-induced IBD injury by regulating the Treg/Th17 balance and related cytokine secretion to reduce the DAI and colonic tissue damage. Thus, AG490 may be a new method for effective treatment of IBD.

Mitochondrial bioenergetics, uncoupling protein-2 activity, and reactive oxygen species production in the small intestine of a TNBS-induced colitis rat model.

Inflammatory bowel disease (IBD) is often associated with a decrease in energy-dependent nutrient uptake across the jejunum that serves as the main site for absorption in the small intestine. This association has prompted us to investigate the bioenergetics underlying the alterations in jejunal absorption in 2,4,6-trinitrobenzenesulfonic acid-induced colitis in rats. We have found that mitochondrial oxygen consumption did not change in state 2 and state 3 respirations but showed an increase in state 4 respiration indicating a decrease in the respiratory control ratio of jejunal mitochondria during the peak of inflammation. This decrease in the coupling state was found to be guanosine diphosphate-sensitive, hence, implicating the involvement of uncoupling protein-2 (UCP2). Furthermore, the study has reported that the production of reactive oxygen species (ROS), known to be activators of UCP2, correlated negatively with UCP2 activity. Thus, we suggest that ROS production in the jejunum might be activating UCP2 which has an antioxidant activity, and that uncoupling of the mitochondria decreases the efficiency of energy production, leading to a decrease in energy-dependent nutrient absorption. Hence, this study is the first to account for an involvement of energy production and a role for UCP2 in the absorptive abnormalities of the small intestine in animal models of colitis.

Biochemical evaluation and molecular docking assessment of the anti-inflammatory potential of Phyllanthus nivosus leaf against ulcerative colitis

Ulcerative colitis (UC) is an inflammation of the colon that can progress to colorectal cancer if left untreated. No medication completely cures UC and natural products are sources of alternative approaches. This study aimed to determine the anti-inflammatory potential of Phyllanthus nivosus leaf extract and fractions in a rat model of ulcerative colitis and to identify the active ingredients. UC was induced in rats by intra-rectal infusion of 1ml of 4% acetic acid (AA) in normal saline. AA exposed groups of rats were treated with 100 mg/kg bodyweight of methanol extract, hexane, ethyl-acetate and butanol fractions orally for four days. Another group received the standard drug - Dexamethasone and control rats were given distilled water only. Some biochemical changes were evaluated and the active ingredients were identified using Gas Chromatography-Mass Spectrometry (GC-MS) followed by molecular docking against interleukin-1-beta converting enzyme (Caspase-1), beta-2 adrenergic receptor (ADRB2), cyclooxygenase-2 (COX-2) and tumour necrosis factor-alpha (TNF-α). Exposure of rat colon to acetic acid significantly altered (p < 0.05) serum levels of tumour necrosis factor-alpha (TNF-α), interleukin – 6 (IL-6), nitric oxide (NO), lipid peroxidation product (malondialdehyde or MDA), reduced glutathione (GSH); and activities of superoxide dismutase (SOD) and catalase (CAT). These alterations were however restored in the rats treated with P. nivosus leaf with the ethyl-acetate fraction displaying the highest ameliorative activity. GC-MS analysis of the ethyl acetate fraction revealed the presence of 40 compounds which when subjected to molecular docking demonstrated varying degrees of binding affinities for the protein targets. Ethyl iso-allocholate demonstrated the highest binding affinity for caspase-1, cholest-22-ene-21-ol, 3,5-dehydro-6- methoxy-, pivalate for ADRB2 and TNF-α; and alpha-cadinol for COX-2. The anti-inflammatory potential of Phyllanthus nivosus leaf as a natural remedy and as a source of new drugs against ulcerative colitis is validated.

Dark Purple Luem Pua rice extract reduces disease severity in rat models of inflammatory bowel disease

Purpose: To investigate the effects of an aqueous extract of unpolished dark purple glutinous Thai rice, variety Luem pua (LP), in two rat models of inflammatory bowel disease (IBD).&#x0D; Methods: Polyphenolic compounds content were determined by HPLC methods and antioxidant activities by DPPH and FRAP assays of the LP extract. The effect of the LP extract at 5 g/kg/day were evaluated in two rat models of IBD that included acetic acid and indomethacin induced IBD. On each day of treatment, changes of body weight, stool consistency and stool blood were scored and expressed as disease activity index (DAI). At the end of the experiments, the animals were euthanized. Colon length and spleen weight were determined, and the degree of inflammation of the colon was scored.&#x0D; Results: Rats in both models of IBD (acetic acid- and indomethacin-induced IBD), exhibited significant increases in DAI, macroscopic inflammation scores and spleen weights, while the lengths of colon were decreased. Pretreatment with LP extract attenuated the disease severity in both models as seen by the reverse of all observed altered parameters.&#x0D; Conclusion: These data suggest that LP extract might be beneficial in preventing and/or treating IBD.&#x0D; Keywords: Inflammatory bowel disease (IBD), Dark purple glutinous rice Var. Luem Pua, Acetic acid, Indomethacin

Dairy Propionibacterium freudenreichii ameliorates acute colitis by stimulating MUC2 expression in intestinal goblet cell in a DSS-induced colitis rat model

An intact mucus layer is important in managing inflammatory bowel disease (IBD). Dairy Propionibacterium freudenreichii has probiotic potential, produces propionic acid and is known to promote health. The aim of this study was to evaluate the effects of P. freudenreichii on the improvement of colitis. LS 174T goblet cells and a dextran sodium sulfate (DSS)-induced colitis rat model were used to investigate the P. freudenreichii-induced stimulation of mucin production in vitro and in vivo, respectively. The mRNA and protein expression levels of MUC2, a main component of intestinal mucus, increased in the supernatant of P. freudenreichii culture (SPFC)-treated LS 174 cells. The SPFC and live P. freudenreichii (LPF) reduced the disease activity index (DAI) in the rats with DSS-induced colitis. After treatment with SPFC or LPF, the mRNA levels of typical pro-inflammatory cytokines decreased and the inflammatory state was histologically improved in the rats with DSS-induced colitis. The SPFC and LPF treatments increased the gene and protein expression levels of MUC2 in the rats with DSS-induced colitis compared with the expression levels in the negative control rats, and immunohistochemistry (IHC) showed an increase of the intestinal MUC2 level. In addition, SPFC and LPF augmented the level of propionate in the faeces of the rats with DSS-induced colitis. In conclusion, P. freudenreichii might improve acute colitis by restoring goblet cell number and stimulating the expression of MUC2 in intestinal goblet cells.

The Ventrolateral Periaqueductal Gray Contributes to Depressive-Like Behaviors in Recovery of Inflammatory Bowel Disease Rat Model.

BackgroundPatients with inflammatory bowel disease (IBD) experience depression, even in the remission phase of IBD symptoms. Although mapping depression-associated brain regions through the gut-brain axis can contribute to understanding the process, the mechanisms remain unclear. Our previous results support the idea that glutamatergic transmission in the ventrolateral periaqueductal gray (vlPAG) mediates stress-induced depression-like behaviors. Thus, we hypothesize that the vlPAG plays a role in regulating depression during remission of IBD.MethodsWe used dextran sulfate sodium (DSS)-induced visceral pain model to evoke depression-like behaviors, assessed by tail suspension test (TST) and sucrose preference test (SPT), and electrophysiological recordings from vlPAG.ResultsSymptoms of animals modeling IBD were relieved by replacing DSS solution with normal drinking water, but their depression-like behaviors sustained. Moreover, the impairment of glutamatergic neurotransmission in vlPAG was sustained as well. Pharmacologically, microinfusion of the glutamate receptor 1 (GluR1) antagonist NASPM into vlPAG mimicked the depression-like behaviors. Furthermore, intra-vlPAG application of AMPA and AMPA receptor-mediated antidepressant (2R,6R)-hydroxynorketamine [(2R,6R)-HNK] reversed the DSS-induced depression-like behaviors in the remission phase of visceral abnormalities.ConclusionOur results suggest that vlPAG glutamatergic transmission mediates depression-like behaviors during remission of DSS-induced visceral pain, suggesting that vlPAG mapping to the gut-brain axis contributes to depression during remission of IBD.

Protective effects of panax notoginseng saponin on dextran sulfate sodium-induced colitis in rats through phosphoinositide-3-kinase protein kinase B signaling pathway inhibition.

BACKGROUNDIntestinal inflammation is a common digestive tract disease, which is usually treated with hormone medicines. Hormone medicines are effective to some extent, but long-term use of them may bring about many complications.AIMTo explore the protective effects of panax notoginseng saponin (PNS) against dextran sulfate sodium (DSS)-induced intestinal inflammatory injury through phosphoinositide-3-kinase protein kinase B (PI3K/AKT) signaling pathway inhibition in rats.METHODSColitis rat models were generated via DSS induction, and rats were divided into control (no modeling), DSS, DSS + PNS 50 mg/k, and DSS + PNS 100 mg/kg groups. Then, the intestinal injury, oxidative stress parameters, inflammatory indices, tight junction proteins, apoptosis, macrophage polarization, and TLR4/AKT signaling pathway in colon tissues from rats in each of the groups were detected. The PI3K/AKT signaling pathway in the colon tissue of rats was blocked using the PI3K/AKT signaling pathway inhibitor, LY294002.RESULTSCompared with rats in the control group, rats in the DSS group showed significantly shortened colon lengths, and significantly increased disease activity indices, oxidative stress reactions and inflammatory indices, as well as significantly decreased expression of tight junction-associated proteins. In addition, the DSS group showed significantly increased apoptotic cell numbers, and showed significantly increased M1 macrophages in spleen and colon tissues. They also showed significantly decreased M2 macrophages in colon tissues, as well as activation of the PI3K/AKT signaling pathway (all P < 0.05). Compared with rats in the DSS group, rats in the DSS + PNS group showed significantly lengthened colon lengths, decreased disease activity indices, and significantly alleviated oxidative stress reactions and inflammatory responses. In addition, this group showed significantly increased expression of tight junction-associated proteins, significantly decreased apoptotic cell numbers, and significantly decreased M1 macrophages in spleen and colon tissues. This group further showed significantly increased M2 macrophages in colon tissues, and significantly suppressed activation of the PI3K/AKT signaling pathway, as well as a dose dependency (all P < 0.05). When the PI3K/AKT signaling pathway was inhibited, the apoptosis rate of colon tissue cells in the DSS + LY294002 group was significantly lower than that of the DSS group (P < 0.05).CONCLUSIONPNS can protect rats against DSS-induced intestinal inflammatory injury by inhibiting the PI3K/AKT signaling pathway, and therefore may be potentially used in the future as a drug for colitis.

A deep learning approach to evaluate intestinal fibrosis in magnetic resonance imaging models

Fibrosis may be introduced as a severe complication of inflammatory bowel disease (IBD). This is a particular disorder causing luminal narrowing and stricture formation in the inflamed bowel wall of a patient denoting, possibly, need for surgery. Thus, the development of treatments reducing fibrosis is an urgent issue to be addressed in IBD. In this context, we require the finding and development of biomarkers of intestinal fibrosis. Potential candidates such as microRNAs, gene variants or fibrocytes have shown controversial results on heterogeneous sets of IBD patients. Magnetic resonance imaging (MRI) has been already successfully proven in the recognition of fibrosis. Nevertheless, while there are no numerical models capable of systematically reproducing experiments, the usage of MRI could not be considered a standard in the inflammatory domain. Hence, there is an importance of deploying new sequence combinations in MRI methods that enable learning reproducible models. In this work, we provide reproducible deep learning models of intestinal fibrosis severity scores based on MRI novel radiation-induced rat model of colitis that incorporates some unexplored sequences such as the flow-sensitive alternating inversion recovery or diffusion imaging. The results obtained return an $$87.5\%$$ of success in the prediction of MRI scores with an associated mean-square error of 0.12. This approach offers practitioners a valuable tool to evaluate antifibrotic treatments under development and to extrapolate such noninvasive MRI scores model to patients with the aim of identifying early stages of fibrosis improving patients’ management.

Flos lonicerae flavonoids attenuate experimental ulcerative colitis in rats via suppression of NF-κB signaling pathway.

This study sought to isolate active Flos lonicerae flavonoids and evaluate their anti-oxidative and anti-inflammatory effects as well as investigate the molecular mechanistic action of these flavonoids in the rat model of ulcerative colitis (UC). Total flavonoids and three flavonoids (hyperoside, lonicerin, and luteolin) were isolated from honeysuckle and purified via column purification. Rat model of UC was established via 2,4,6-trinitrobenzene sulfonic acid (TNBS) intoxication. The anti-oxidative and anti-inflammatory effects of the three flavonoids against TNBS-induced UC were evaluated by measuring appropriate biomarkers via assay kit. The effects of hyperoside, lonicerin, and luteolin on the regulation of nuclear factor-kappa B (NF-κB) pathway were investigated using Western blot (WB) and real-time polymerase chain reaction (RT-PCR) while their protective effects on UC were also elucidated. Pretreatment with flavonoids (hyperoside, lonicerin, and luteolin at 25-100mg/kg) and sulfasalazine (SSZ, positive control at 100mg/kg) substantially attenuated TBNS-induced UC. Also, the flavonoids significantly reduced the levels of respective serum oxidative and proinflammatory markers such as superoxide dismutase (SOD), myeloperoxidase (MPO), malondialdehyde (MDA), prostaglandins E2 (PGE2), tumor necrosis factor-alpha (TNF-α), interleukin-beta (IL-β), and C-reactive protein (CRP). In addition, the flavonoids remarkably inhibited the expression of NF-κB signaling pathway. F. lonicerae flavonoids (hyperoside, lonicerin, and luteolin) demonstrated potent anti-UC activities in TBNS-induced UC rat model via anti-oxidative and anti-inflammatory effects through the inhibition of NF-κB signaling pathway.

Therapeutic effects of combination of platelet lysate and sulfasalazine administration in TNBS-induced colitis in rat

Inflammatory bowel disease (IBD) is a chronic and idiopathic disease with gastrointestinal dysfunction. Current therapeutic approaches in IBD have several limitations such as, harmful side effects and high price for biologic drugs. It sounds that finding of an effective, safe and inexpensive strategy to overcome IBD is critical. Platelet derivatives, as biological pool of wide range of growth factors and cytokines, are widely used in regenerative medicine for treatment of soft and hard tissue lesions. We sought to determine whether platelet lysate (PL) alone or in combination with sulfasalazine (reference drug) can be a valuable strategy for overcoming IBD. In the present study, we investigated and compared the daily and alternate-day administration of PL alone or combined with sulfasalazine for treating colitis in a rat model of IBD. Histological damage scores of TNBS-induced colitis were reduced by co-administration of every alternate day PL and sulfasalazine. Pro-inflammatory cytokines TNF-α, IL-1 and IL-6 were decreased and anti-inflammatory cytokines IL-10 and TGF-β were increased after treatment with PL compared to that in the TNBS group. Furthermore, combined treatment with PL and sulfasalazine decreased apoptosis and inhibited the NF‐κB signaling pathway. In conclusion, the combined administration of PL with conventional IBD therapy is able to effectively ameliorate IBD through modulation of inflammatory status.

Efficacy of resveratrol encapsulated microsponges delivered by pectin based matrix tablets in rats with acetic acid-induced ulcerative colitis

Objectives: The objective of the present work to encapsulate the resveratrol (RES) inside the chitosan-based microsponges, employing the systematic optimization by 33 Box–Behnken design for the colonic targeting. Significance: Enhanced therapeutic efficacy of RES-loaded microsponges and matrix tablets, vis-a-vis pureRES for ulcerative colitis. Methods: RES-loaded microsponges were prepared employing the systematic optimization by 33 Box–Behnken design for the colonic targeting. The best-optimizedRES-loaded microsponge was compressed in the form of a tablet, employing pectin as a matrix-forming material. The encapsulation of RES inside microsponge was confirmed by XRD, DSC and FT-IR. Further, both RES-loaded microsponges and matrix tablets were evaluated for in vitro release kinetics and further evaluated for in vivo ulcerative colitis animal model. Results: Optimization experiments was obtained as the high value of r 2 (particle size = 0.9999; %EE = 0.9652; %CDR = 0.9469) inferred excellent goodness of fit. SEM revealed nearly spherical and porous nature of RES-loaded microsponges. The in vitro release kinetic showed zero-order release for RES-loaded microsponges and Korsmeyer–Peppas model for matrix tablets. The pharmacodynamic studies, in ulcerative colitis rat model, indicated better therapeutic efficacy of drug-loaded microsponges and matrix tablets, vis-a-vis pure RES. Thus, the present study advocates the potential of RES based microsponges delivered by pectin based matrix tablet, in the treatment of various colonic disorders. Conclusion: The present study proved that RES-loaded microsponges and matrix tablets based on chitosan and pectin can be the ideal delivery system for colonic delivery of RES.

Evaluation of Budesonide-Hydroxypropyl-β-Cyclodextrin Inclusion Complex in Thermoreversible Gels for Ulcerative Colitis.

New formulations for topical treatment of ulcerative colitis with budesonide inclusion complex (BUDHP-β-CD) and poloxamers (PL) were developed for future clinical use. This study evaluated the efficacy of such novel formulations in a rat model of colitis. The PL-BUDHP-β-CD systems were prepared by direct dispersion of the complex (BUD concentration 0.5mgmL-1) in solutions with PL407 or PL403. Male Wistar rats underwent TNBS-induced colitis and were treated for 5days by a rectal route, as follows: BUD 1: BUDHP-β-CD + PL407 (18%); BUD 2: BUDHP-β-CD + PL407 (20%); BUD 3: BUDHP-β-CD + PL407 (18%) + PL403 (2%); BUD 4: plain BUD; BUD 5: BUDHP-β-CD; C1: HP-β-CD + PL407 (18%); C2: HP-β-CD + PL407 (20%); C3: HP-β-CD + PL407 (18%) + PL403 (2%); C4: saline. A negative control group without colitis was also used. Colitis was assessed via myeloperoxidase (MPO) activity, and macroscopic and microscopic damage score in colon tissues. Protein levels of TNF-α, IL-1β, IL-10 and endogenous glucocorticoids were obtained using ELISA. BUDHP-β-CD poloxamer formulations had similar MPO activity when compared with the negative control group. All formulations presented lower MPO activity than BUDHP-β-CD and plain BUD (p < 0.001). BUD 2 produced lower microscopic score values than plain BUD and BUDHP-β-CD (p < 0.01). All formulations with BUDHP-β-CD poloxamers reduced TNF-α levels (p < 0.05). Novel budesonide inclusion complex formulations improved microscopic damage and reduced colonic MPO activity and TNF-α levels.

Encapsulation of Escherichia coli strain Nissle 1917 in a chitosan―alginate matrix by combining layer-by-layer assembly with CaCl2 cross-linking for an effective treatment of inflammatory bowel diseases

Escherichia coli strain Nissle 1917 (EcN) has been widely shown to effectively treat inflammatory bowel diseases (IBDs). Unfortunately, after oral administration, EcN viability dramatically decreases due to severe environmental factors, including low gastric pH, temperature and osmotic pressure. To address these challenges and improve oral bio-availability, this study utilized layer-by-layer assembly (LbL) and ionic cross-linking with CaCl2 as a method of EcN encapsulation (GEcN). Upon examination, GEcN cells were shown to maintain their ability to grow and proliferate, but had a slightly longer stationary phase (10 h) relative to free EcN (4 h). When exposed to simulated gastric fluid (SGF), a higher number of GEcN cells survived up to 12 h when compared to the other groups. To assess the therapeutic effect of EcN encapsulation in vivo, a TNBS-induced colitis rat model was established. When compared with the oral administration of free EcN, GEcN exhibited a significantly enhanced anti-inflammatory effect. Furthermore, GEcN treatment showed a lower disease activity index (DAI), decreased pro-inflammatory cytokine expression (MPO, TNF-α, IL-6) and increased anti-inflammatory cytokine expression (IL-10). Additionally, rats that received GEcN had much higher ZO-1 expression levels. These results suggest that EcN encapsulation in a chitosan―alginate matrix when utilizing the LbL assembly with CaCl2 cross-linking can improve probiotic viability in a gastric environmental and thereby offer a more effective treatment for IBDs.

Colon-Targeted Therapy of Tacrolimus (FK506) in the Treatment of Experimentally Induced Colitis

Background/Aims: Inflammatory bowel disease is a chronic or remitting/relapsing intestinal inflammation, which comprises Crohn’s disease and ulcerative colitis (UC). Severe UC is a life-threatening condition that requires corticosteroids (CS) as a first-line rescue therapy. Some patients are refractory to CS and may require alternative immunosuppressive therapy. Oral tacrolimus (FK506), an immunosuppressive agent, has been reported to be effective in the management of severe refractory UC, but it can cause serious adverse effects. This work aims to study the effect of tacrolimus delivered by a colon-targeted delivery system (CTDS) in a dextran sulfate sodium (DSS)-induced animal model of colitis. Materials and Methods: We developed and evaluated an oral CTDS of tacrolimus (FK506) loaded pH-dependent polymeric microspheres, composed of Eudragit® S100 as a pH-sensitive polymer using the oil-in-water emulsion method. The physicochemical properties and drug release profiles of these microparticles in gastrointestinal tract (GIT) conditions were examined. A DSS-induced colitis rat model was used to evaluate the potential remedial and in vivo distribution of microspheres. Results: The pH-microspheres prevented a burst drug release in acidic pH conditions and showed sustained release at a colonic pH. The in vivo distribution study in the rat GIT demonstrated that pH-microspheres were successfully delivered to the inflamed colon. Moreover, it also demonstrated a significant decrease of disease activity and expression of proinflammatory cytokines, such as tumor necrosis factor α, interleukin-1β (IL-1β), and IL-6, and minimized the histological and morphometric changes. Conclusion: The results confirmed the efficacy of tacrolimus (FK506) CTDs in the management of DSS-induced colitis.

Anti-Inflammatory, Antioxidant, and Microbiota-Modulating Effects of Camellia Oil from Camellia brevistyla on Acetic Acid-Induced Colitis in Rats.

Altering the microbiota by the daily diet is highly associated with improved human health. Studies confirms the gastrointestinal protective and anti-inflammatory effects of camellia oil; however, the benefits in gut microbiota remain unclear. Camellia oils of Camellia oleifera (PCO) and C. brevistyla (TCCO) were used to evaluate probiotic growth in vitro. In addition, the protective effects of camellia oils in the acetic acid (AA)-induced colitis rat model were investigated. In vitro fermentation study showed the proliferation of Lactobacillus spp. and Bifidobacterium spp. from human intestinal microbiota was increased after TCCO treatment. Moreover, the rats pretreated with TCCO exhibited significantly less AA-induced colonic injury and hemorrhage, higher serum immunoglobulin G 1 (IgG 1) levels, lower malondialdehyde levels, and lower inflammatory cytokine production in the colon tissue compared with those in the PCO group. Surprising, the protective effect against acetic acid-induced colitis by TCCO was similar to sulfasalazine (positive control) treatment. Moreover, TCCO increased the richness and diversity of probiotics in gut microbiota. TCCO alleviated AA-induced colitis by modulating gut microbiota, reducing oxidative stress and suppressing inflammatory responses.

Effect of N-acetylcysteine on an experimental model of indomethacin induced inflammatory bowel disease

N-acetylcysteine (NAC) is a thiol compound can act both as a precursor of GSH and as a direct ROS scavenger. Moreover, NAC has been purported to have anti-inflammatory properties. The aim of this study was to investigate the effects of NAC on a rat model of inflammatory bowel disease (IBD). Model of IBD was induced by subcutaneous Indomethacin (Indo) at a dose rate of 9 mg/kg for two days at 24 h intervals. NAC in two doses (500mg/Kg, 1 g/kg body weight po) was administrated for seven consecutive days beginning 24 h after the first Indo injection. Body weight loss, small intestine weight / length ratio, macroscopic damage, histological study, as well as by biochemical measurement of reduced glutathione (GSH) and superoxide dismutase (SOD) activity in the small intestine tissue were used for assessment of small intestinal injury. NAC in two doses especially at dose (1g/kg) revealed increase in small intestine weight/length ratio, macroscopic and microscopic small intestinal damage scores caused by administration of indomethacin with no statistical significance comparing with Indo control group (p>0.05). The increased of the oxidative stress was observed in both doses of NAC especially at dose (1g/kg) by decrease the levels of GSH and SOD activity with no statistical significance comparing with Indo control group (p>0.05). The conclusion of this study is NAC didn&#39;t enhance intestinal inflammation induced by Indo (rat model of IBD) in both doses, in contrast rising in inflammation and oxidative stress was observed in NAC treated groups especially at dose 1g/kg