Rat Colon Tissue Research Articles

Effect of medicated thread moxibustion of Chinese Zhuang Minority medicine on colonic inflammatory impairment and Th17/IL-17F signaling in rats with ulcerative colitis

To observe the effect of medicated thread moxibustion of Zhuang Minority medicine on helper T cell 17 (Th17)/ Interleukin-17F(IL-17F) signaling pathway in ulcerative colitis (UC) rats, so as to explore its mechanisms underlying improvement of UC. Forty male SD rats were randomly divided into normal control, model, medication and medicated thread moxibustion (MTM) groups, with 10 rats in each group. The UC model was induced by free drinking of 4% dextran sulfate sodium (DSS) for 10 d. After successful modeling, rats of the medication group were treated by gavage of salazosulfapyridine (SASP). Medicated thread moxibustion was applied to unilateral "Tianshu" (ST25) and "Qihai" (CV6) alternatively for rats of the MTM group, once daily for 14 d. The body mass, stool shape, and fecal occult test were recorded and conducted daily to perform disease activity index (DAI) score. H．E. staining was used to display pathological changes of the colon tissue. The Th17 cells and IL-17F and retinoic acid related orphan receptor γ t (ROR-γt) in the colon tissue were detected by flow cytometry, and enzyme-linked immunosorbent assay (ELISA), respectively, and the expression levels of RORγt and IL-17F mRNA in colon tissue were detected by quantitive real-time PCR. After modeling, the DAI score, colonic Th17 percentage, RORγt and IL-17F contents, and RORγt and IL-17F mRNA expression were significantly increased in the model group in contrast to the normal control group (P<0.01, P<0.05). Following the intervention, all the aforementioned indexes were reversed in both medication and MTM groups (P<0.01, P<0.05). No significant differences were found between the medication and MTM groups in the levels of the above mentioned indexes (P>0.05, except RORγt and IL-17F mRNA expression). H．E. staining showed disappearance of goblet cells, infiltration of a large number of inflammatory cells, exfoliation of the epithelial tissue and edema of colonic mucosal in rats of the model group, which was relatively milder in both medication and MTM groups. Medicated thread moxibustion of Zhuang Minority medicine can reduce the inflammatory damage of colon tissue in UC rats, which is associated with its effects in suppressing the expression of RORγt, production of Th17 cells, and secretion of pro-inflammatory factor IL-17F in colon tissue.

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.

MiR-195 alleviates ulcerative colitis in rats via MAPK signaling pathway.

To study the effect of micro ribonucleic acid (miR)-195 on the inflammatory response of ulcerative colitis (UC) model rats and to explore its regulatory mechanism, thus providing a new scheme for the clinical treatment of UC. A rat model of UC was prepared by 2, 4, 6-trinitrobenzenesulfonic acid (TNBS)/ethanol assay, and the rats were randomly divided into Control group, Model group, and miR-195 mimic (miR-195 agomir) group. The disease activity index (DAI) in each group was observed. Hematoxylin and eosin (H&E) staining was utilized to detect the pathological changes in the rat colon tissues in each group. The levels of interleukin-6 (IL-6) and IL-1β in the colon tissues of the rats in each group were detected by enzyme-linked immunosorbent assay (ELISA). In addition, the messenger RNA (mRNA) and protein levels of p38 mitogen-activated protein kinase (p38 MAPK) and tumor necrosis factor-alpha (TNF-α) in the colon tissues of each group of rats were examined via Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and Western blotting, respectively. Compared with those in Control group, the rats in Model group had an increased DAI score, severely pathologically damaged colon tissues, raised levels of IL-6 and IL-1β in the colon tissues and significantly elevated mRNA and protein levels of p38 MAPK and TNF-α. In comparison with those in Model group, the DAI score was decreased, the pathological damage to the rat colon tissues was improved, the levels of IL-6 and IL-1β in the rat colon tissues were reduced, and the mRNA and protein levels of p38 MAPK and TNF-α were notably lowered in miR-195 agomir group. MiR-195 mimics can alleviate the pathological damage to the colon and inflammatory responses in UC model rats, and its mechanism may be related to the inhibition on the p38 MAPK signaling pathway.

Shaoyao-Gancao Decoction Relieves Visceral Hyperalgesia in TNBS-Induced Postinflammatory Irritable Bowel Syndrome via Inactivating Transient Receptor Potential Vanilloid Type 1 and Reducing Serotonin Synthesis.

Postinflammatory irritable bowel syndrome (PI-IBS) is a common functional gastrointestinal disorder, which is characterized by abdominal pain, low-grade inflammation, and visceral hypersensitivity. Shaoyao-Gancao decoction (SGD) has been used to improve the clinical symptoms of abdominal spasmodic pain accompanying acute gastroenteritis, but the underlying therapeutic mechanism has not been fully elucidated. In the present study, a rat model of PI-IBS was established via rectal administration of TNBS. Rats were scored daily for 28 days using disease activity index (DAI). Abdominal withdrawal reflex (AWR) was used to measure the pain threshold. After SGD (6.25, 12.5, and 25 g/kg/d) treatment for 14 days, rat colonic tissue was collected for histopathological grading, enterochromaffin (EC) cell count, and 5-HT content measurement. RT-qPCR and western blot analyses were employed to detect the gene and protein level of tryptophan hydroxylase (TPH), serotonin reuptake transporter (SERT), and transient receptor potential vanilloid 1 (TRPV1). To further validate the effect of SGD on TRPV1, another experiment was performed in cells. The results revealed that visceral hyperalgesia, reflected by increased DAI, AWR, pathological injury score, 5-HT content, and EC cell count in PI-IBS rats, was significantly ameliorated by SGD. In cells, SGD markedly inhibited the expression and function of TRPV1. Moreover, the expression levels of TPH were also repressed by SGD. The findings of the present study indicated that the therapeutic effect of SGD on visceral hyperalgesia may be closely associated with the regulatory role of TRPV1 and 5-HT signaling pathways.

Effect of Sorbus domestica and its active constituents in an experimental model of colitis rats induced by acetic acid.

In Turkish folk medicine, leaves of Sorbus domestica are used for the treatment of burns, cough, stomachache, bradyuria, kidney stone. The fruits of this plant are used for diarrhoea. This study was carried out to investigate the effect of S. domestica on ulcerative colitis induced by acetic acid in rats. The crude methanolic extract of fruits was sequentially fractionated into five subextracts; dichloromethane, diethyl ether, ethyl acetate, n-butanol and aqueous extracts. Effects of the extract, subextracts and fractions were investigated in acetic acid-induced rat colitis model. The colonic interleukin-6 (IL-6), tumor necrosis factor (TNF-α), nitrite, superoxide dismutase (SOD), glutathione (GSH), lipid peroxidation (LPO), catalase (CAT), and malondialdehyde (MDA) levels as well as the caspase-3 and myeloperoxidase (MPO) activities were measured to determine the activity. Histopathological analyzes were also performed on the colon tissue of rats. The methanolic extract and diethylether subextract have led to a noteworthy decrease in MPO, caspase-3, IL-6, TNF-α, MDA, and nitrite levels in the colon tissue and blood. In addition, histopathological analysis results were supported by biochemical parameters. After confirmation of the activity against ulcerative colitis, the diethyl ether subextract was subjected to more chromatographic separation for the isolation of compounds 1, 2 and 3. The structures of these three compounds were elucidated as vanillic acid 4-O-α-L-rhamnopyranoside (1), protocateuic acid anhydrite (2) and trivanilloyl-(1,3,4-trihydroxybenzol) ester (3). In this study, the potential of S. domestica in the treatment of colitis was investigated. Fruits of this plant were found to have important anti-inflammatory and antioxidant activities. Through isolation techniques, vanillic acid 4-O-α-L-rhamnopyranoside, protocateuic acid anhydrite and trivanilloyl-(1,3,4-trihydroxybenzol) ester were determined as the main active components of the fruits. Consequently, S domestica might be a promising candidate for upcoming use the prevention and treatment of various disorders, such as inflammatory bowel diseases, irritable bowel syndrome and Clostridium difficile infection.

Brain orexin improves intestinal barrier function via the vagal cholinergic pathway

Orexins are neuropeptides that are implicated in a number of functions. With regard to the gastrointestinal functions, orexin acts centrally to regulate gastric secretion, gastrointestinal motility and visceral sensation. Little is however known about a role of central orexin in the control of intestinal barrier function. The present study was performed to clarify whether brain orexin plays a role in the control of intestinal permeability. Colonic permeability was estimated in vivo by quantifying the absorbed Evans blue in colonic tissue in rats. Intracisternally administered orexin-A but not orexin-B dose-dependently blocked the increased intestinal permeability by lipopolysaccharide (LPS) or corticotropin-releasing factor while intraperitoneally injected orexin-A failed to block it. Atropine or vagotomy abolished the action by central orexin-A. Intravenous injection of 2-deoxy-D-glucose (2-DG), a central vagal stimulant, significantly blocked the LPS-induced increase in intestinal permeability and atropine prevented the action of 2-DG. Intracisternal injection of SB-334687, a selective orexin 1 receptor antagonist, significantly blocked the action of 2-DG-induced improvement of intestinal hyperpermeability. These results suggest that exogenously administered or endogenously released orexin acts centrally to improve the intestinal hyperpermeability by LPS via the vagal cholinergic pathway. The findings also suggest for the first time that the brain could control intestinal permeability. The neuronal rapid protective advantage to the host by improving the intestinal barrier function by the neuropeptide may help us understand the brain-gut interaction in stress sensitive gastrointestinal disorders like irritable bowel syndrome associated with the altered intestinal permeability.

Evaluation of Sucrose Laurate as an Intestinal Permeation Enhancer for Macromolecules: Ex Vivo and In Vivo Studies.

Oral delivery of macromolecules requires permeation enhancers (PEs) adaptable to formulation. Sucrose laurate (SL) (D1216), a food grade surfactant, was assessed in Caco-2 monolayers, isolated rat intestinal tissue mucosae, and rat intestinal instillations. Accordingly, 1 mM SL increased the apparent permeability coefficient (Papp) of [14C]-mannitol and reduced transepithelial electrical resistance (TEER) across monolayers. It altered expression of the tight junction protein, ZO-1, increased plasma membrane potential, and decreased mitochondrial membrane potential in Caco-2 cells. The concentrations that increased flux were of the same order as those that induced cytotoxicity. In rat colonic tissue mucosae, the same patterns emerged in respect to the concentration-dependent increases in paracellular marker fluxes and TEER reductions with 5 mM being the key concentration. While the histology revealed some perturbation, ion transport capacity was retained. In rat jejunal and colonic instillations, 50 and 100 mM SL co-administered with insulin induced blood glucose reductions and achieved relative bioavailability values of 2.4% and 8.9%, respectively, on a par with the gold standard PE, sodium caprate (C10). The histology of the intestinal loops revealed little damage. In conclusion, SL is a candidate PE with high potential for emulsion-based systems. The primary action is plasma membrane perturbation, leading to tight junction openings and a predominant paracellular flux.

Dapsone reduced acetic acid-induced inflammatory response in rat colon tissue through inhibition of NF-kB signaling pathway

Aim: The purpose of this study is to examine the protective effects of Dapsone on inflammation of intestinal tissue through inhibition of NF-kB pathway in acetic acid-induced colitis in rats.Methods: Acute colitis was produced by intra-rectal instillation of 2 mL of 4% acetic acid diluted in normal saline. Then, two hours after induction of colitis, DMSO as vehicle, dexamethasone (2 mg/kg) and dapsone (12.5 mg/kg) were given to the animals intraperitoneally (i.p.) and continued for five following days. Evaluation of macroscopic and microscopic damages were done. Myeloid peroxidase enzyme (MPO) activity was measured by a biochemical technique. Moreover, tumor necrosis factor-α (TNF-α) activity was identified by ELISA, and the expression level of pNF-kB protein was evaluated by immunohistochemistry (IHC).Results: Dexamethasone (2 mg/kg) and dapsone (12.5 mg/kg) decreased the macroscopic and microscopic damages compared with acetic acid group (p ˂ .001). Additionally, these agents decreased the activity of MPO (p ˂ .001), TNF-α (p ˂ .001) and the expression level of p-NF-kB (p ˂ .001) in rat colon tissue compared with the acetic acid group.Conclusion: It is proposed that the anti-inflammatory activity of dapsone on acetic acid-induced colitis in rats may involve the inhibition of NF-kB pathway.

Effect of Annona muricata Leaves Extract on Colon Antioxidant Status and Ketone Bodies in Blood and Urine of Cycas-treated Rats

The effect of Annona muricata methanol leaf extract (AMELE) on colon antioxidant status and ketone bodies in blood and urine of cycas treated rats was investigated. Seventy male Wistar albino rats were randomly assigned into seven groups of ten experimental animals in a study that lasted for twenty-eight days. After 28 days, using standard methods, serum and urinary ketone bodies were assayed. Malondialdehyde (MDA), antioxidants enzymes in the colon and histopathological analysis were assayed. The results showed ketogenic diet had significant (p&lt;0.05) increase in serum and urinary ketone body levels compared to other groups on normal feed. Annona muricata extract enhanced cellular consumption and uptake of ketone bodies whereas cycas reduced cellular consumption of ketone bodies. Annona muricata given either with ketogenic diet or cycas or with both ketogenic diet and cycas led to higher tissue levels of antioxidant enzymes. Tissue MDA levels were significantly (p&lt;0.05) increased in all cycas treated groups compared to the control group with the highest levels seen in the two groups placed on normal feed and cycas. Lactate dehydrogenase activities were significantly (p&lt;0.05) increases in all the groups placed on ketogenic diet compared to the groups placed on normal feed. Histopathological analysis revealed normal rat colon tissues in all the groups except 43% of the group 2 animals. This therefore indicates that cycas- induced oxidative stress and tissue injury may be mitigated by the combined administration of Annona muricata extract and ketogenic diet.

The potential anti-inflammatory effect of Omega-3 polyunsaturated fatty acids on experimentally induced ulcerative colitis in rats

Ulcerative Colitis(UC) is one of the major inflammatory Bowel Syndrome(IBD) which show incremental incidence worldwide. In the present study, the potential protective and curative effects and the molecular mechanisms of Omega-3 polyunsaturated fatty acids(ω-3PUFAs) in rat model of acetic acid-induced UC were investigated. Forty male albino rats were divided into five equal groups. Group I:( Control normal group) received no drugs. GroupII:(Early ulcerative colitis-induced group)rats received 2 ml(3%v/v) glacial acetic-acid intra-colonially at the 21st day of the experiment and sacrificed 3 days later of acetic acid administration. Group III:(Early ulcerative colitis+omega-3protected group) rats received Omega-3(300mg/kg body-weight/day) orally for 21 days prior to glacial acetic acid administration and sacrificed 3 days later. Group IV:(Late ulcerative colitis-induced group) rats received glacial acetic-acid similar to group II for 3 successive days and sacrificed after 21 days. Group V:(Late ulcerative colitis+Omega-3 treated group) rats first administered with acetic-acid then after 3 days Omega-3 was administered for 21 days. The results showed significant increase in L-Malondialdehyde(L-MDA) and Myeloperoxidase(MOP) activity with marked decrease in reduced glutathione(GSH) and Catalase(CAT) activity in colon tissue of UC-induced rats as compared with control group. However, a significant depletion of colon tissue L-MDA,MOP activity and obvious increase in GSH concentration and CATactivity was observed after Omega-3 administration compared to UC-non-treated group. Additionally, a significant up-regulation of mRNA gene expression levels of (IL-1β), Caspase-3 and down-regulation in Bcl-2 observed in colon tissue of UC-induced rats. However,the expression levels of IL-1β and Caspase-3 were down-regulated and Bcl-2 was up-regulated after administration of Omega-3.

Hesperidin Improves Colonic Motility in Loeramide-Induced Constipation Rat Model via 5-Hydroxytryptamine 4R/cAMP Signaling Pathway

Fructus has motivation effect on gastrointestinal tract. Hesperidin is extracts of Fructus, and we attempted to prove its effects on improving the gastrointestinal transmission function and determine the possible mechanisms by a loperamide-induced slow transit constipation (STC) model. Constipation phenotypes were measured in rats with Lop-induced constipation after treatment with hesperidin. The amounts and water content of stool were significantly higher in the hesperidin-treated group than the loperamide-induced model group, whereas food intake was maintained at constant levels. Moreover, intestinal transit rate was increased in the treatment group of hesperidin. Histological alteration was detected by H&E staining, we found that the colon smooth muscle cells and neuron cells of the rats were increased, and the infiltration of inflammatory cells was decreased in the hesperidin-treated group compared with the loperamide-induced model group. 5-Hydroxytryptamine (5-HT) receptor4 fluorescence intensity and intracellular-free calcium ions in colon tissue were increased, and relative protein of cAMP/PKA pathway and p-cAMP response component-binding protein (CREB) pathway were upregulated in the hesperidin-treated group compared with the loperamide-induced model group. Further, SMCs from colon tissue of rats were cultured and identified. We found hesperidin could significantly promote tegaserod-induced increase of 5-HTR4 fluorescence intensity, intracellular calcium ions, relative protein of cAMP/PKA pathway and p-CREB pathway, and cell proliferation and inhibit GR113808-induced decrease of 5-HTR4 fluorescence intensity, 5-HTR4 pathway-related proteins (ADCY3, cAMP, PKA, and p-CREB), intracellular calcium ions, and cell proliferation. The analysis of our data suggested that hesperidin could obviously improve the gastrointestinal transmission function in loperamide-induced STC rat model via increasing the 5-HTR4 and intracellular-free calcium ions to enhance the expression of relative protein of cAMP/PKA pathway and p-CREB pathway. Hesperidin could be used in the treatment of STC, and our data not only provide experimental basis for the treatment of STC in hesperidin but also provides a theoretical reference for clinical treatment.

Qualitative Fingerprint Analysis and Multidirectional Assessment of Different Crude Extracts and Essential Oil from Wild Artemisia santonicum L.

Artemisia species are used as folk medicines in several countries. This work was aimed to shed more light on the effect of methanol, water, ethyl acetate extracts, and essential oil (EO) of A. santonicum on selected enzymes (cholinesterase, tyrosinase α-amylase, and α-glucosidase) as well of their antioxidant and pharmacological effects. The chemical profile of the essential oil was determined using gas chromatography coupled to mass spectrometry (GC-MS) analysis, while the extracts were chemically characterized by high performance liquid chromatography coupled to mass spectrometry (HPLC-MS). Forty-nine constituents were identified and camphor (36.6%), 1,8-cineole (10.2%), α-thujone (10.1%), borneol (4.5%), and β-thujone (3.6%) were the major components. Overall, 45, 74, and 67 components were identified from the ethyl acetate, methanol, and water extracts, respectively. The EO and extracts showed significant antioxidant properties, in a cell-free model; particularly, methanol and water extracts revealed promising sources of antioxidant compounds. Additionally, we evaluated protective effects of EO and extracts in isolated rat colon tissue challenged with lipopolysaccharide (LPS), as an ex vivo model of colon inflammation, and human colon cancer HCT116 cell line. Particularly, we observed that, among all tested samples, A. santonicum ethyl acetate displayed the best pharmacological profile, being able to blunt LPS-induced levels of all tested biomarkers of inflammation and oxidative stress, including colon nitrites, lactate dehydrogenase, prostaglandin E2, and serotonin. Additionally, this extract was also able to reduce HCT116 cell viability, thus suggesting potential antiproliferative effects against colon cancer cells. Based on our results, A. santonicum has great potential for developing novel functional agents including pharmaceuticals, cosmeceuticals, and nutraceuticals.

Electroacupuncture improves intestinal function by down-regulating expression of 5-HT1AR and c-fos proteins in the hypothalamus and colon tissues via brain-gut axis in rats with functional diarrhea

To observe the effect of electroacupuncture (EA) on expression of 5-HT1A receptor (5-HT1AR) and c-fos proteins in the hypothalamus and colon tissues in functional diarrhea (FD) rats so as to explore its underlying mechanisms in improving intestinal function via brain-gut axis. A total of 40 SD rats were randomized into blank control, model, EA Tianshu (ST25)-Dachangshu (BL25, ST25-BL25) and EA Quchi (LI11)- Shangjuxu (ST37, LI11-ST37) groups. The FD model was established by gavage of Folium Sennae (10 mg/kg) and constraint immobilization once daily for 29 days. EA (10 Hz/50 Hz, 1.5 mA) was applied to bilateral ST25 and BL25 in EA ST25-BL25 group, and bilateral LI11 and ST37 in EA LI11-ST37 group for 20 min, once daily for successive 10 days. The expression of 5-HT1AR and c-fos protein in the hypothalamus and colon tissues was determined by using Western blot. The state of stool was recorded for calculating the loose stool rate and diarrhea index. After modeling, the loose stool rate, diarrhea index and expression levels of 5-HT1AR and c-fos proteins in the colon and hypothalamus tissues were obviously increased in the model group in contrast with the blank control group(P<0.01，P<0.05). Following EA intervention, the loose stool rate and diarrhea index, the expression levels of 5-HT1AR and c-fos proteins in the hypothalamus and colon in the EA ST25-BL25 group, and the expression of 5-HT1AR in the colon in the EA LI11-ST37 group were significantly down-regulated relevant to the model group (P<0.01，P<0.05). No significant changes were found in loose stool rate and diarrhea index，and the expression levels of hypothalamic 5-HT1AR and hypothalamic and colonic c-fos proteins in the EA LI11-ST37 group (P>0.05). The expression levels of 5-HT1AR protein in the hypothalamus and c-fos protein in the hypothalamus and colon in the EA LI11-ST37 group were significantly up-regulated relevant to the EA ST25-BL25 group (P<0.05). EA of ST25-BL25 can down-regulate expression of 5-HT1AR and c-fos proteins in the hypothalamus and colon tissue in FD rats, which may contribute to its function in improving symptoms of FD possibly via brain-gut axis.

Potential Mechanisms of 3, 4-Oxo-Isopropylidene-Shikimic Acid in Ameliorating 2, 4, 6-Trinitrobenzenesulfonic Acid-Induced Colitis in Rats.

Previously, we reported that 3, 4-oxo-isopropylidene-shikimic acid (ISA) has therapeutic potential in experimental colitis in rats. This study aimed to elucidate the potential mechanisms of ISA on the inflammatory response in rats with 2, 4, 6-trinitrobenzenesulfonic acid-induced colitis. After the induction of colitis, rats were orally administered ISA for 12 days. Then, the expression levels of inflammatory cytokines, cell adhesion molecules, and matrix metalloproteinase (MMP) in the blood and colon tissues, and the protein level of nuclear factor kappa B (NF-κB) p65 in cytoplasm and nucleus of colon tissues were evaluated. As a result, an enhanced inflammatory response was observed in rats with experimental colitis. However, the treatment with ISA significantly ameliorated the inflammatory response, which was manifested as a significant decrease in the levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, interferon (IFN)-γ, IL-8, TNF-α mRNA, P-selectin, E-selectin, intercellular cell adhesion molecule-1, MMP9 and MMP9 mRNA in rat blood and colon tissues, respectively, and a significant decrease in the levels of IFN-γ/IL-4, and the NF-κBp65 activity coefficient. Therefore, the therapeutic effect of ISA on experimental colitis may be related to its inhibitory effect on the expression of cytokines, adhesion molecules, and MMP9, which may be involved in the inhibition of the activation and nuclear translocation of NF-κBp65.

Regulating effect of baicalin on IKK/IKB/NF-kB signaling pathway and apoptosis-related proteins in rats with ulcerative colitis

ObjectiveThis study was aimed to explore effect of baicalin on IKK/IKB/NF-kB signaling pathway and apoptosis-related proteins in rats with ulcerative colitis (UC). MethodsHistopathological observation and scores of colon tissue were performed in the UC rat model. IKK/IKB/NF-kB signaling pathway and apoptosis-related proteins were measured by Western blotting. ResultsBaicalin significantly increased the activity of SOD, CAT and GSH-Px in colon tissue of rats with UC, but significantly decreased the content of MDA, IL-1β, MPO, PEG2 and TNF-α in colon tissue of rats with UC. In the molecular mechanism, baicalin significantly decreased the expression of cleaved-caspase3, cleaved-caspase9, Bcl-2/Bax, cyt-c, NF-kB p-65, p-IKKβ/IKKβ and p-IKBα/IKBα. Baicalin could significantly inhibit p-IKBα/IKBα content change, but had no significant effect on p-IKKβ/IKKβ. ConclusionBaicalin may have a regulating effect on IKK/IKB/NF-kB signaling pathway and apoptosis-related proteins in UC rats.

Double Drug Delivery Using Capped Mesoporous Silica Microparticles for the Effective Treatment of Inflammatory Bowel Disease.

Silica mesoporous microparticles loaded with both rhodamine B fluorophore (S1) or hydrocortisone (S2), and capped with an olsalazine derivative, are prepared and fully characterized. Suspensions of S1 and S2 in water at an acidic and a neutral pH show negligible dye/drug release, yet a notable delivery took place when the reducing agent sodium dithionite is added because of hydrolysis of an azo bond in the capping ensemble. Additionally, olsalazine fragmentation induced 5-aminosalicylic acid (5-ASA) release. In vitro digestion models show that S1 and S2 solids are suitable systems to specifically release a pharmaceutical agent in the colon. In vivo pharmacokinetic studies in rats show a preferential rhodamine B release from S1 in the colon. Moreover, a model of ulcerative colitis is induced in rats by oral administration of 2,4,6-trinitrobenzenesulfonic acid (TNBS) solutions, which was also used to prove the efficacy of S2 for colitis treatment. The specific delivery of hydrocortisone and 5-ASA from S2 material to the colon tissue in injured rats markedly lowers the colon/body weight ratio and the clinical activity score. Histological studies showed a remarkable reduction in inflammation, as well as an intensive regeneration of the affected tissues.

Effect of Shaoyao Tang on ulcerative colitis in rats via regulation of TLR4/NF-κB signal pathway

The aim of this paper was to investigate the effect of Shaoyao Tang on ulcerative colitis(UC) in rats via regulation of TLR4/NF-κB signal pathway. A total of 56 Wistar rats were randomly divided into 6 groups: normal control group(double distilled water), model group(double distilled water), mesalazine group(10 mL·kg~(-1)), high dose, middle dose and low dose Shaoyao Tang groups(2.4, 1.2, and 0.6 g·mL~(-1)). After UC rat models were established by 2, 4-dinitrochlorobenzene(DNCB)/ethanol enema, the rats received double distilled water or corresponding drugs twice a day for 7 days. After the treatment cycle, the general performance and disease activity index(DAI) of rats were observed on the next day. Then the rats were sacrificed. The length of colon was measured. Macroscopic and histological score of colon were evaluated. Histopathological changes of colon were observed by HE staining. Ultraviolet spectrophotometry detection was used to detect the content of myeloperoxidase(MPO) in blood and colon tissues. The levels of P-selectin, macrophage migration inhibitory factor(MIF) and thromboxane B_2(TXB_2) in blood and colon tissues were determined by ELISA. Immunohistochemistry and Western blot analysis were performed to detect the protein expressions of TLR4 and NF-κB in colon tissues. The results showed that as compared with the model group, Shaoyao Tang of different doses improved the general performance of UC rats. Moreover, high-dose Shaoyao Tang group showed the most obvious effect in scoring of disease activity index(P<0.001); both medium and high doses of Shaoyao Tang significantly inhibited the colon shortening and pathological injury, with significantly decreased expression levels of MPO, P-selectin, MIF and TXB_(2 )in serum and colon tissues of UC rats(P<0.001). Immunohistochemistry and Western blot assay showed that the levels of TLR4 and NF-κB protein expression in the colon tissues of Shaoyao Tang high-dose group were remarkably lower than that in the model group(P<0.001). This study shows that Shaoyao Tang has protective and repairing effects on UC, and its possible mechanism is achieved probably by regulating the TLR4/NF-κB pathway and inhibiting the expressions of MPO, P-selectin, MIF and TXB_2.

Thymol reduces acetic acid-induced inflammatory response through inhibition of NF-kB signaling pathway in rat colon tissue.

The aim of the present study was to evaluate the anti-inflammatory effect of thymol in acetic acid-induced rat colitis through inhibiting the NF-κB signaling pathway. Colitis was induced by intra-rectal administration of 2mL of diluted acetic acid (4%) solution using a flexible plastic rubber catheter in Wistar rats. Colitis was induced on the first day and all treatments were applied 5days after the induction of colitis. Thymol was dissolved in 0.2% tween 80 in saline and administered orally at doses of 10, 30, and 100mg/kg per day. Macroscopic and histopathologic investigations were done. The expression of myeloperoxidase (MPO) and tumor necrosis factor-α (TNF-α) was determined by immunohistochemistry (IHC) assay. The protein expression level of pNF-κB p65 was measured by the Western blot technique. Treatment with thymol reduced mucosal and histological damages compared to the acetic acid group. Our results showed that thymol markedly inhibited the production of MPO and TNF-α in the colon tissue of the acetic acid-induced group. In addition, thymol decreased acetic acid-induced up-regulation of pNFκB p65 protein. The results of our study suggest that thymol exerts an anti-inflammatory effect in acetic acid-induced rat colitis by inhibiting the NF-κB signaling pathway and downregulating TNF-α and MPO expressions.

Construing the Biochemical and Molecular Mechanism Underlying the In Vivo and In Vitro Chemotherapeutic Efficacy of Ruthenium-Baicalein Complex in Colon Cancer.

In pursuit of a novel approach in colon cancer therapy, we explored the ability of ruthenium baicalein complex to eradicate colon cancer by efficiently targeting various apoptotic pathways on human colon cancer cell line and on a DMH and DSS induced murine model of colorectal cancer. In this study, we provide direct proof of the chemotherapeutic potential of the ruthenium baicalein complex by activating p-53 dependent intrinsic apoptosis and modulating the AKT/mTOR and WNT/β- catenin pathways. The ruthenium baicalein complex was synthesized and its characterizations were accomplished through various spectroscopic techniques followed by assessment of antioxidant potential by DPPH, FRAP, and ABTS methods. In vitro study established that the complex increased p53 and caspase-3 expressions while down regulating VEGF and mTOR expression, induced apoptosis, and DNA fragmentation in the HT-29 cells. Acute and sub-acute toxicity study was also considered and results from in vivo study revealed that complex was effective in suppressing ACF multiplicity and hyperplastic lesions and also raised the CAT, SOD, and glutathione levels. Furthermore, the complex decreased cell proliferation and increased apoptotic events in tumor cells correlated with the upregulation of Bax and downregulation of Bcl2, WNT and β- catenin expressions. Our findings from the in vitro and in vivo study provide robust confirmation that ruthenium baicalein complex possesses a potential chemotherapeutic activity against colon cancer and is competent in reducing ACF multiplicity, hyperplastic lesions in the colon tissues of rats by inducing apoptosis.

Effects of diet with different vitamin D concentration on visceral sensitivity in rats with irritable bowel syndrome

Objective To explore the mechanism of vitamin D in the genesis of irritable bowel syndrome (IBS). Methods A total of 50 newborn Sprague Dawley (SD) rats were divided into three model groups and two control groups (saline control group and normal control group). The model was induced by dilute acetic acid enema. After rats were weaned, the rats of three IBS model groups were fed with normal diet, vitamin D deficient diet and vitamin D sufficient diet, respectively. The visceral sensitivity of the rats was assessed by the colorectal distention experiment. The intestinal tissues of rats was taken for histological score, and the intestinal mast cell (MC) was also counted. The mRNA level of vitamin D receptor (VDR) in colon tissues of rats was determined by real-time reverse transcription-polymerase chain reaction (RT-PCR). T test or rank sum test was performed for statistical analysis. Results When the water volume of balloon was 0.5 mL and 1.0 mL, the abdominal withdrawal reflex (AWR) scores of male rats of the vitamin D deficient model group were 2.67±0.33 and 3.60±0.28, which were higher than those of normal vitamin D model group (1.93±0.15 and 3.20±0.18), and the differences were statistically significant (t=4.491 and 2.683, both P 0.05). The number of MC in the mucosal tissue of the sigmoid colon of female rats in IBS model group was 41.00±19.80, which was higher than that in normal control group (12.40±5.35), and the difference was statistically significant (t=3.118, P=0.030). The number of MC in the mucosal tissue of ileum of the female rats in vitamin D deficiency model group was 16.00±3.71, which was higher than that in normal vitamin D model group (7.30±2.66), and the difference was statistically significant (t=4.263, P=0.003). The VDR mRNA level in the colon tissues of male model rats of normal vitamin D model group was 1.48±0.33, which was higher than that of saline control group and normal control group (0.97±0.21 and 1.00±0.21; t=2.590 and 2.482, both P<0.05). The VDR mRNA levels in colon tissues of female rats of vitamin D deficient model group was 1.90±0.66, which was higher than that of normal control group (1.00±0.14), and the difference was statistically significant (t=2.649, P=0.038). Conclusions Vitamin D may affect visceral hypersensitivity in IBS, and MC may involve in vitamin D induced visceral hypersensitivity. Key words: Irritable bowel syndrome; Vitamin D; Models, animal; Mast cells; Visceral sensitivity