OBJECTIVETo prepare the diammonium glycyrrhizinate-loaded chitosan nanoparticles (DG-CS NPs), and evaluate its pharmaceutical properties and pharmacodynamic effects on ulcerative colitis (UC).

METHODDG-CS NPs were prepared by spray drying method and optimized by orthogonal design. The morphology, size and in vitro release of DG-CS NPs were investigated. The therapeutic effects of DG-CS NPs on UC mice induced by dextran sulfate were evaluated preliminarily through disease active index method.

RESULTThe size of DG-CS NPs with loading capacity about (51.25 +/- 1.75)% was in the range of 300-600 nm. The release of DG-CS NPs was associated with environmental pH value and displayed significant therapeutic and preventive effects on UC.

CONCLUSIONDG-CS NPs prepared by spray drying method showed efficacy on UC mice.

Animals ; Chitosan ; chemistry ; Colitis, Ulcerative ; chemically induced ; drug therapy ; Dextran Sulfate ; toxicity ; Disease Models, Animal ; Female ; Glycyrrhizic Acid ; chemistry ; therapeutic use ; Male ; Mice ; Nanoparticles ; chemistry

BACKGROUNDDisrupted Ca2+ homeostasis contributes to the development of colonic dysmotility in ulcerative colitis (UC), but the underlying mechanisms are unknown. This study aimed to examine the alteration of colonic smooth muscle (SM) Ca2+ signaling and Ca2+ handling proteins in a rat model of dextran sulfate sodium (DSS)-induced UC.

METHODSMale Sprague-Dawley rats were randomly divided into control (n = 18) and DSS (n = 17) groups. Acute colitis was induced by 5% DSS in the drinking water for 7 days. Contractility of colonic SM strips (controls, n = 8 and DSS, n = 7) was measured in an organ bath. Cytosolic resting Ca2+ levels (n = 3 in each group) and Ca2+ transients (n = 3 in each group) were measured in single colonic SM cells. Ca2+ handling protein expression was determined by Western blotting (n = 4 in each group). Differences between control and DSS groups were analyzed by a two-sample independent t-test.

RESULTSAverage tension and amplitude of spontaneous contractions of colonic muscle strips were significantly enhanced in DSS-treated rats compared with controls (1.25 ± 0.08 g vs. 0.96 ± 0.05 g, P= 0.007; and 2.67 ± 0.62 g vs. 0.52 ± 0.10 g, P= 0.013). Average tensions of carbachol-evoked contractions were much weaker in the DSS group (1.08 ± 0.10 g vs. 1.80 ± 0.19 g, P= 0.006). Spontaneous Ca2+ transients were observed in more SM cells from DSS-treated rats (15/30 cells) than from controls (5/36 cells). Peak caffeine-induced intracellular Ca2+ release was lower in SM cells of DSS-treated rats than controls (0.413 ± 0.046 vs. 0.548 ± 0.041, P= 0.033). Finally, several Ca2+ handling proteins in colonic SM were altered by DSS treatment, including sarcoplasmic reticulum calcium-transporting ATPase 2a downregulation and phospholamban and inositol 1,4,5-trisphosphate receptor 1 upregulation.

CONCLUSIONSImpaired intracellular Ca2+ signaling of colonic SM, caused by alteration of Ca2+ handing proteins, contribute to colonic dysmotility in DSS-induced UC.

Animals ; Colitis ; chemically induced ; metabolism ; Colon ; cytology ; metabolism ; Dextran Sulfate ; toxicity ; Male ; Muscle, Smooth ; metabolism ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; physiology

The aim of this paper was to investigate the effect of Banxia Xiexin Decoction(BXD) on inflammatory factors and intestinal flora in a dextran sulfate sodium induced ulcerative colitis(DSS-UC) mouse model, and to explore the mechanism of BXD in treating ulcerative colitis from the perspective of flora disorder. Forty C57 BL/6 J mice were randomly divided into control group, model group and BXD group. A 2.5% DSS-induced ulcerative colitis model was established. On the 8 th day, normal saline, normal saline, and BXD were given daily for 14 days. After 14 days, HE staining was used to observe histopathological changes of the colon. Serum inflammatory factor content was detected by ELISA, and the change of intestinal flora in mice feces was detected by 16 S rRNA sequencing technology. Compared with control group, the colonic tissue of mice in model group was damaged seriously, and the contents of IL-6 and TNF-α in serum were significantly increased(P<0.05). Compared with model group, mice in BXD group had less colonic damage, and the contents of IL-6, TNF-α in serum were decreased significantly(P<0.05). After creation, the richness of Patescibacteria was increased significantly at the phylum level(P<0.05). At the same time, the richness of Faecalibaculum(P<0.01), norank_f_Muribaculaceae(P<0.01) were decreased significantly at the genus level, while the richness of Turicibacter(P<0.01), Romboutsia(P<0.01), Clostridium_sensu_stricto_1(P<0.01) were increased significantly. After the intervention with BXD, the content of Patescibacteria was significantly reduced at the phylum level(P<0.05), and the contents of Lactobacillus(P<0.01), Clostri-dium_sensu_stricto_1(P<0.01), Enterorhabdus(P<0.01), Candidatus_Saccharimonas(P<0.05), Eubacterium_fissicatena_group(P<0.05) were decreased significantly at the genus level, while the contents of Dubosiella, Bacteroides and Allobaculum were increased significantly. Therefore, BXD could significantly improve the symptoms of DSS-UC mice. It not only could reduce the contents of IL-6 and TNF-α, but also could reduce the richness of Patescibacteria at the phylum level, and those of Clostridium_sensu_stricto_1, Candidatus_Saccharimonas, Eubacterium_fissicatena_group at the genus level. Inaddition, BXD could increase the richness of Bacteroides and Bifidobacterium. It suggested that BXD could play a role in the treatment of ulcerative colitis partially through reducing inflammatory factors and regulating the structure of the gut microbiota.
Animals ; Colitis ; Colitis, Ulcerative/drug therapy* ; Colon ; Dextran Sulfate/toxicity* ; Disease Models, Animal ; Drugs, Chinese Herbal ; Gastrointestinal Microbiome ; Mice ; Mice, Inbred C57BL ; Sulfates

This study explored the mechanism of Sanhuang Decoction(SHD) in treating dextran sulfate sodium(DSS)-induced ulcerative colitis(UC) in mice with Candida albicans(Ca) colonization via high-throughput transcriptome sequencing. Specifically, the animal model was established by oral administration of 3.0% DSS for 7 days followed by intragastrical administration of Ca suspension at 1.0 × 10~8 cells for 4 days and then the mice were treated with SHD enema for 7 days. Afterwards, the general signs were observed and the disease activity index(DAI) was recorded every day. After mice were sacrificed, colon length and colon mucosa damage index(CMDI) were determined and the histomorphology was observed with the HE staining method. The fungal loads of feces were detected with the plate method. Anti-saccharomyces cerevisiae antibody(ASCA) and β-1,3-glucan in serum, and TNF-α, IL-1β, and IL-6 in serum and colon were detected by ELISA. High-throughput RNA sequencing method was adopted to identify transcriptome of colon tissues from the control, model and SHD(15.0 g·kg~(-1)) groups. Differentially expressed genes(DEGs) among groups were screened and the GO and KEGG pathway enrichment analysis of the DEGs was performed. The expression levels of NLRP3, ASC, caspase-1, and IL-1β genes related to the NOD-like receptor signaling pathway which involved 9 DEGs, were examined by qRT-PCR and Western blot. The results demonstrated that SHD improved the general signs, decreased DAI and Ca loads of feaces, alleviated colon edema, erosion, and shortening, and lowered the content of β-1,3-glucan in serum and TNF-α, IL-1β, and IL-6 in serum and colon tissues of mice. Transcriptome sequencing revealed 383 DEGs between SHD and model groups, which were mainly involved in the biological processes of immune system, response to bacterium, and innate immune response. They were mainly enriched in the NOD-like signaling pathway, cytokine-cytokine interaction pathway, and retinol metabolism pathway. Moreover, SHD down-regulated the mRNA and protein levels of NLRP3, caspase-1, and IL-1β. In a word, SHD ameliorates DSS-induced UC in mice colonized with Ca, which probably relates to its regulation of NOD-like receptor signaling pathway.
Animals ; Candida albicans/genetics* ; Colitis, Ulcerative/genetics* ; Colon ; Dextran Sulfate/toxicity* ; Disease Models, Animal ; Drugs, Chinese Herbal ; High-Throughput Nucleotide Sequencing ; Mice ; Transcriptome

OBJECTIVETo investigate the anti-colon cancer effects of berberine and possible relationship with cyclooxygenase-2.

METHODWistar rat colon cancer model was induced by 1-2 dimethylhydrazine (DMH) (40 mg x kg(-1), sc) + 1% dextran sodium sulfate solution (DSS) (freely drinking). All rats were randomly divided into 3 groups: Control (DMH + DSS + solvant), meloxicam (Mel) (DMH + DSS + Mel 1.35 mg x kg(-1)), berberine (Ber) (DMH + DSS + Ber 100 mg x kg(-1)). The drugs were given orally once a day for 5 day per week. The body weight, the number of colon ACFs, the incidence and number of colon cancer in rats, as well as the morphological changes of rat colon tissues were evaluated. Human colon cancer lovo cell line was treated by either Ber or Mel in various concentrations (1 10(-6) mol x L(-1), 1 x 10(-5) mol x L(-1), 1 x 10(-4) mol x L(-1), 1 x 10(-3) mol x L(-1)) for 6, 12 and 24 h, respectively, and the cell growth was assayed by MTT method. RT-PCR and western-blot were used to evaluate the mRNA and protein expressions of COX-2 from lovo cells treated with Ber and Mel.

RESULTBer significantly improved the dyscrasia induced by DMH + DSS, the both of body weight and general condition were better than control group. Ber also significantly inhibited ACF and colon cancer incidence in the rats treated by DMH + DSS for 10 weeks or 20 weeks, which was similar to that of Mel. Ber inhibited the proliferation of lovo cells in concentration- and time-dependent manners, and the IC50 values were significantly smaller than that of Mel at 6, 12 and 24 h after lovo cells were treated by either Ber or Mel. Ber also concentration-dependently decreased expressions of COX-2 mRNA and COX-2 protein from lovo cells.

CONCLUSIONBer can inhibit ACF and tumor formation induced by DMH + DSS, and decrease the lovo cell proliferation index. The anti-tumor effects of Ber may involve in an unknown pathway through which the expressions of COX-2 mRNA and protein were inhibited.

1,2-Dimethylhydrazine ; toxicity ; Aberrant Crypt Foci ; prevention & control ; Animals ; Berberine ; therapeutic use ; Body Weight ; drug effects ; Colonic Neoplasms ; enzymology ; prevention & control ; Cyclooxygenase 2 ; genetics ; Dextran Sulfate ; toxicity ; Female ; Male ; RNA, Messenger ; analysis ; Rats ; Rats, Wistar

Pai-Nong-San (PNS), a prescription of traditional Chinese medicine, has been used for years to treat abscessation-induced diseases including colitis and colorectal cancer. This study was aimed to investigate the preventive effects and possible protective mechanism of PNS on a colitis-associated colorectal cancer (CAC) mouse model induced by azoxymethane (AOM)/dextran sodium sulfate (DSS). The macroscopic and histopathologic examinations of colon injury and DAI score were observed. The inflammatory indicators of intestinal immunity were determined by immunohistochemistry and immunofluorescence. The high throughput 16S rRNA sequence of gut microbiota in the feces of mice was performed. Western blot was used to investigate the protein expression of the Wnt signaling pathway in colon tissues. PNS improved colon injury, as manifested by the alleviation of hematochezia, decreased DAI score, increased colon length, and reversal of pathological changes. PNS treatment protected against AOM/DSS-induced colon inflammation by regulating the expression of CD4
Animals ; Azoxymethane/toxicity* ; CD8-Positive T-Lymphocytes ; Colitis/genetics* ; Dextran Sulfate/toxicity* ; Disease Models, Animal ; Drugs, Chinese Herbal/pharmacology* ; Glycogen Synthase Kinase 3 beta ; Mice ; Mice, Inbred C57BL ; RNA, Ribosomal, 16S ; Wnt Signaling Pathway/drug effects*

BACKGROUNDIt has been reported that CD8(+) regulatory cells could be induced upon oral tolerance. The purpose of this study was to investigate the changes of CD8α(+) T cells in dextran sulfate sodium (DSS)-induced colitis mice pretreated by oral immune regulation.

METHODSThe effects of five low oral doses of colitis-extracted proteins (CEP) on colitis were evaluated by clinical manifestation and histological lesions. The percentages of CD8α(+) T cells gating on CD3(+) T cells were evaluated in the gut-associated lymphoid tissues (GALT) and the spleens by flow cytometry. Differences between the two groups were compared by Student's t test or Mann-Whitney U test.

RESULTSCompared to bovine serum albumin (BSA)-fed control mice, administration of CEP resulted in marked alleviation of colitis. The proportion of CD8α(+) T cells, not only in intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs) of the large intestine (LI) but also in spleen from CEP-fed colitis mice, was significantly higher than that from BSA-fed colitis mice (LI-IELs: (71.5 ± 5.4)% vs. (60.1 ± 4.3)%, P < 0.01; LI-LPLs: (60.7 ± 5.2)% vs. (51.9 ± 4.7)%, P < 0.01; spleen: (24.1 ± 3.6)% vs. (20.3 ± 4.1)%, P < 0.05; n = 8). Mucosal repair in repair-period mice five days after termination of DSS treatment was also accompanied by an increase of CD8α(+) T cells in large intestinal mucosal lymphocytes (LI-IELs: (72.1 ± 3.7)% vs. (61.5 ± 4.5)%, P < 0.01; LI-LPLs: (62.1 ± 5.7)% vs. (52.7 ± 3.6)%, P < 0.01; n = 8). The proportion of CD3(+) T cells increased in Peyer's patches (PPs) and decreased in mesenteric lymph nodes (MLNs) from colitis mice compared to untreated mice, whereas the change pattern of CD3(+) T cells in PPs and MLNs from CEP-fed colitis mice was just on the contrary.

CONCLUSIONImprovement of DSS-induced colitis resulted from oral immune regulation is associated with an increase in CD8α(+) T cells in spleen and large intestinal mucosa.

Administration, Oral ; Animals ; CD8-Positive T-Lymphocytes ; metabolism ; Colitis ; chemically induced ; complications ; Dextran Sulfate ; toxicity ; Flow Cytometry ; Lymphocytes ; cytology ; metabolism ; Male ; Mice ; Mice, Inbred BALB C ; Proteins ; administration & dosage ; immunology ; Spleen ; cytology ; metabolism

OBJECTIVETo study the effect of total coumarins (TC) from Urtica dentata on dextran sulfate sodium (DSS)-induced colitis in mice.

METHODThe colitis model was established by administering DSS. Having been treated with TC, their body weight was determined. Concentrations of IL-6, IL-10, TGF-beta1 and IFN-gamma were monitored by ELISA. Colon samples were collected for the histopathological examination. Western blot was used to detect TLR4 and NF-kappaB protein expression in colonic tissues.

RESULTTCs from U. dentata effectively controlled the body weight loss of mice with colitis, down-regulated the concentration of IL-6 and IFN-gamma and increased the suppressive cytokines IL-10 and TGF-beta1 in the serum. Additionally, TC alleviated the mucosal damage and decreased the expressions of TLR4 and NF-kappaB in colonic tissues.

CONCLUSIONTCs from U. dentata shows the anti-inflammatory effect on colitis in mice by reducing the expressions of TLR4 and NF-kappaB in colonic tissues and regulating pro-and anti-inflammatory cytokines.

Animals ; Colitis ; drug therapy ; metabolism ; Coumarins ; therapeutic use ; Cytokines ; blood ; Dextran Sulfate ; toxicity ; Disease Models, Animal ; Male ; Mice ; Mice, Inbred BALB C ; NF-kappa B ; antagonists & inhibitors ; Toll-Like Receptor 4 ; antagonists & inhibitors ; Urticaceae ; chemistry

Ulcerative colitis (UC) is a chronic and recurrent inflammatory bowel disease (IBD) that has become a major gastroenterologic problem during recent decades. Numerous complicating factors are involved in UC development such as oxidative stress, inflammation, and microbiota disorder. These factors exacerbate damage to the intestinal mucosal barrier. Spirulina platensis is a commercial alga with various biological activity that is widely used as a functional ingredient in food and beverage products. However, there have been few studies on the treatment of UC using S. platensis aqueous extracts (SP), and the underlying mechanism of action of SP against UC has not yet been elucidated. Herein, we aimed to investigate the modulatory effect of SP on microbiota disorders in UC mice and clarify the underlying mechanisms by which SP alleviates damage to the intestinal mucosal barrier. Dextran sulfate sodium (DSS) was used to establish a normal human colonic epithelial cell (NCM460) injury model and UC animal model. The mitochondrial membrane potential assay 3-‍‍(4,5-dimethylthiazol-2-yl)-2,‍5-diphenyltetrazolium bromide (MTT) and staining with Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) and Hoechst 33258 were carried out to determine the effects of SP on the NCM460 cell injury model. Moreover, hematoxylin and eosin (H&E) staining, transmission electron microscopy (TEM), enzyme-linked immunosorbent assay (ELISA), quantitative real-time polymerase chain reaction (qPCR), western blot, and 16S ribosomal DNA (rDNA) sequencing were used to explore the effects and underlying mechanisms of action of SP on UC in C57BL/6 mice. In vitro studies showed that SP alleviated DSS-induced NCM460 cell injury. SP also significantly reduced the excessive generation of intracellular reactive oxygen species (ROS) and prevented mitochondrial membrane potential reduction after DSS challenge. In vivo studies indicated that SP administration could alleviate the severity of DSS-induced colonic mucosal damage compared with the control group. Inhibition of inflammation and oxidative stress was associated with increases in the activity of antioxidant enzymes and the expression of tight junction proteins (TJs) post-SP treatment. SP improved gut microbiota disorder mainly by increasing antioxidant enzyme activity and the expression of TJs in the colon. Our findings demonstrate that the protective effect of SP against UC is based on its inhibition of pro-inflammatory cytokine overproduction, inhibition of DSS-induced ROS production, and enhanced expression of antioxidant enzymes and TJs in the colonic mucosal barrier.
Animals ; Antioxidants/pharmacology* ; Colitis/prevention & control* ; Colitis, Ulcerative/metabolism* ; Colon/metabolism* ; Dextran Sulfate/toxicity* ; Disease Models, Animal ; Gastrointestinal Microbiome ; Inflammation/metabolism* ; Mice ; Mice, Inbred C57BL ; Oxidative Stress ; Reactive Oxygen Species/metabolism* ; Spirulina

OBJECTIVETo investigate the changes of miR-155 and its target genes in colitis-associated carcinogenesis.

METHODSColitis-associated colon cancer was induced by azoxymethane (AOM) and dextran sulfate sodium (DSS) in C57BL/6 mice. Mice of three different stages during the development of colon cancer were obtained, named AD1, AD2 and AD3, respectively. A control group of mice without any treatment and a DSS only group representing chronic inflammation without cancer were set up as well. Colon tissue was collected and expression of miR-155 in the colon tissues was measured by real-time fluorescent quantitative PCR. TargetScan and PicTar were used to predict potential target genes of miR-155, which were then preliminarily screened with our gene expression microarray database of AOM-DSS mouse model. Regular PCR was used to confirm the changes of the expression of these potential target genes in AOM-DSS mouse model.

RESULTSColitis-associated colon cancer was effectively induced by azoxymethane and dextran sulfate sodium in C57BL/6 mice. Histological examination revealed that the evolution process was sequentially from normal, mild dysplasia, moderate dysplasia, and severe dysplasia to adenocarcinoma in the AOM-DSS mouse model. The level of miR-155 was gradually elevated with the formation of colitis-associated colon cancer. There was no significant difference between the levels of miR-155 expression in the DSS group (0.005 6 ± 0.003 7) and control group (0.012 0 ± 0.005 1) (P > 0.05), but the level of miR-155 in the AD3 group (0.054 4 ± 0.027 0) was significantly higher than that of the DSS group (0.005 6 ± 0.003 7)(P < 0.01). No significant change of miR-155 expression was found in the DSS only group. The relative expression levels of miR-155 in the control group, DSS only group and AD3 group were 0.012 0 ± 0.005 1, 0.005 6 ± 0.003 7, 0.054 4 ± 0.027 0, respectively. Data analysis with the gene expression microarray showed that Tle4, Kcna1, Itk, Bcorl1, Cacna1c, Rspo2 and Foxo3 were potential target genes of miR-155 in the AOM-DSS mouse model. Changes of Kcna1 and Cacna1c in the AOM-DSS mouse model were validated to be consistent with the changes obtained with the gene expression microarray.

CONCLUSIONThe up-regulation of miR-155 is related to colitis-associated carcinogenesis, but is irrelevant to chronic inflammation in the mouse model.

Adenocarcinoma ; chemically induced ; genetics ; metabolism ; Animals ; Azoxymethane ; toxicity ; Carcinogens ; toxicity ; Cocarcinogenesis ; Colitis ; chemically induced ; genetics ; metabolism ; Colon ; metabolism ; Colonic Neoplasms ; chemically induced ; genetics ; metabolism ; Dextran Sulfate ; toxicity ; Gene Expression Profiling ; Male ; Mice ; Mice, Inbred C57BL ; MicroRNAs ; metabolism ; Precancerous Conditions ; chemically induced ; genetics ; metabolism ; Up-Regulation