scholarly journals Paradoxical regulation of ChAT and nNOS expression in animal models of Crohn's colitis and ulcerative colitis

2013 ◽  
Vol 305 (4) ◽  
pp. G295-G302 ◽  
Author(s):  
John H. Winston ◽  
Qingjie Li ◽  
Sushil K. Sarna
Keyword(s):  
Ulcerative Colitis ◽  
Inflammatory Mediators ◽  
Distal Colon ◽  
Trinitrobenzene Sulfonic Acid ◽  
Mrna Levels ◽  
Functional Changes ◽  
Protein Gene Product ◽  
Dss Colitis ◽  
Nnos Expression

Morphological and functional changes in the enteric nervous system (ENS) have been reported in inflammatory bowel disease. We examined the effects of inflammation on the expression of choline acetyltransferase (ChAT) and nNOS in the muscularis externae of two models of colonic inflammation, trinitrobenzene sulfonic acid (TNBS)-induced colitis, which models Crohn's disease-like inflammation, and DSS-induced colitis, which models ulcerative Colitis-like inflammation. In TNBS colitis, we observed significant decline in ChAT, nNOS, and protein gene product (PGP) 9.5 protein and mRNA levels. In DSS colitis, ChAT and PGP9.5 were significantly upregulated while nNOS levels did not change. The nNOS dimer-to-monomer ratio decreased significantly in DSS- but not in TNBS-induced colitis. No differences were observed in the percentage of either ChAT (31 vs. 33%)- or nNOS (37 vs. 41%)-immunopositive neurons per ganglia or the mean number of neurons per ganglia (55 ± 5 vs. 59 ± 5, P > 0.05). Incubation of the distal colon muscularis externae in vitro with different types of inflammatory mediators showed that cytokines decreased ChAT and nNOS expression, whereas H2O2, a component of oxidative stress, increased their expression. NF-κB inhibitor MG-132 did not prevent the IL-1β-induced decline in either ChAT or nNOS expression. These findings showed that TNBS- and DSS-induced inflammation differentially regulates the expression of two critical proteins expressed in the colonic myenteric neurons. These differences are likely due to the exposure of the myenteric plexus neurons to different combinations of Th1-type inflammatory mediators and H2O2 in each model.

HCl-induced inflammatory mediators in cat esophageal mucosa and inflammatory mediators in esophageal circular muscle in an in vitro model of esophagitis

2006 ◽  
Vol 290 (6) ◽  
pp. G1307-G1317 ◽  
Author(s):  
Ling Cheng ◽  
Weibiao Cao ◽  
Claudio Fiocchi ◽  
Jose Behar ◽  
Piero Biancani ◽  
...  
Keyword(s):  
Inflammatory Mediators ◽  
Platelet Activating Factor ◽  
Circular Muscle ◽  
Muscle Layer ◽  
Normal Mucosa ◽  
Esophageal Mucosa ◽  
Mrna Levels ◽  
Physiol Gastrointest Liver ◽  
Krebs Buffer

Platelet-activating factor (PAF) and interleukin-6 (IL-6) are produced in the esophagus in response to HCl and affect ACh release, causing changes in esophageal motor function similar to esophagitis (Cheng L, Cao W, Fiocchi C, Behar J, Biancani P, and Harnett KM. Am J Physiol Gastrointest Liver Physiol 289: G418–G428, 2005). We therefore examined HCl-activated mechanisms for production of PAF and IL-6 in cat esophageal mucosa and circular muscle. A segment of normal mucosa was tied at both ends, forming a mucosal sac (Cheng L, Cao W, Fiocchi C, Behar J, Biancani P, and Harnett KM. Am J Physiol Gastrointest Liver Physiol 289: G860–G869, 2005) that was filled with acidic Krebs buffer (pH 5.8) or normal Krebs buffer (pH 7.0) as control and kept in oxygenated Krebs buffer for 3 h. The supernatant of the acidic sac (MS-HCl) abolished contraction of normal muscle strips in response to electric field stimulation. The inhibition was reversed by the PAF antagonist CV3988 and by IL-6 antibodies. PAF and IL-6 levels in MS-HCl and mucosa were significantly elevated over control. IL-6 levels in mucosa and supernatant were reduced by CV3988, suggesting that formation of IL-6 depends on PAF. PAF-receptor mRNA levels were not detected by RT-PCR in normal mucosa, but were significantly elevated after exposure to HCl, indicating that HCl causes production of PAF and expression of PAF receptors in esophageal mucosa and that PAF causes production of IL-6. PAF and IL-6, produced in the mucosa, are released to affect the circular muscle layer. In the circular muscle, PAF causes production of additional IL-6 that activates NADPH oxidase to induce production of H2O2. H2O2 causes formation of IL-1β that may induce production of PAF in the muscle, possibly closing a self-sustaining cycle of production of inflammatory mediators.

scholarly journals Lung and Intestine: A Specific Link in an Ulcerative Colitis Rat Model

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Yuan Liu ◽  
Xin-Yue Wang ◽  
Xue Yang ◽  
Shan Jing ◽  
Li Zhu ◽  
...  
Keyword(s):  
Ulcerative Colitis ◽  
Lung Tissue ◽  
Rat Model ◽  
Close Association ◽  
Trinitrobenzene Sulfonic Acid ◽  
Microvascular Endothelium ◽  
Functional Changes ◽  
Liver And Kidney ◽  
Embryonic Origin ◽  
Endothelial Growth Factor

Background. To investigate the link and mechanisms between intestine and lung in the ulcerative colitis (UC) rat model.Materials and Methods. We used the UC rat model by immunological sensitization combined with local 2, 4, 6-trinitrobenzene sulfonic acid (TNBS) in 50% ethanol enema, observed dynamically animal general state and body weight, examined the histological and functional changes in the colon, lung, liver, and kidney tissues, and detected microvascular endothelium response towards inflammation characterized with the expression of iNOS, TXB2, P-selectin, ICAM-1, and vascular endothelial growth factor A (VEGF-A) in the colon and lung tissue.Results. Pulmonary function results suggested ventilator disorder, and pathological findings showed interstitial pneumonia. There were no significant changes in the liver and kidney function and histopathology. The colon and lung tissue iNOS, TXB2, P-selectin, ICAM-1, and VEGF-A expression of the model rats was significantly higher than the normal rats at both time points.Conclusions. Our study is the first to demonstrate the close association between the large intestine and lung in the immune-TNBS-ethanol-induced UC rat model. Different organs and tissues with the same embryonic origin may share the same pathological specificities in a disease. The present study provided a new way of thinking for pathological changes in clinical complex diseases manifested with multiorgan damage.

scholarly journals Nanogels of a Succinylated Glycol Chitosan-Succinyl Prednisolone Conjugate: Release Behavior, Gastrointestinal Distribution, and Systemic Absorption

2020 ◽  
Vol 21 (7) ◽  
pp. 2376
Author(s):  
Haiyan Zhou ◽  
Yuri Ikeuchi-Takahashi ◽  
Yoshiyuki Hattori ◽  
Hiraku Onishi
Keyword(s):  
Ulcerative Colitis ◽  
Plasma Concentrations ◽  
In Vitro Release ◽  
In Vivo Studies ◽  
Systemic Absorption ◽  
Intragastric Administration ◽  
Trinitrobenzene Sulfonic Acid ◽  
Prolonged Release ◽  
Glycol Chitosan

Recently, the potential of nanoparticles (NPs) in ulcerative colitis (UC) therapy has been increasingly demonstrated. Namely, anionic NPs have been found to be accumulated efficiently to the UC damaged area due to epithelial enhanced permeability and retention (eEPR) effect. Previously, a novel anionic nanogel system (NG(S)) was prepared, and evaluated for the efficacy and toxicity. In the present study, release behaviors and biodistribution were investigated in detail to elucidate the functional mechanisms. Rats with 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced ulcerative colitis (UC) were used as biomodels. In vitro release was examined with or without the contents of the cecum or distal colon. Gastrointestinal distribution and plasma concentrations were investigated after the intragastric administration of 10 mg prednisolone (PD) eq./kg. At pH 1.2 and 6.8, release behaviors were slow, but controlled. Overall release was not markedly different irrespective of coexistence of intestinal contents. In in vivo studies, a large amount of PD was distributed in the lower parts of the gastrointestinal tract 6 and 12 h after administration with NG(S). PD accumulated well in the colonic parts, and prolonged release was noted. The systemic absorption of PD with NG(S) was hardly found. NG(S) concentrated the drug in the colon and showed controlled release. These behaviors were considered to lead to the previously reported good results, promotion of effectiveness and suppression of toxic side effects.

scholarly journals Aldosterone induces active K+ secretion by enhancing mucosal expression of Kcnn4c and Kcnma1 channels in rat distal colon

2012 ◽  
Vol 302 (9) ◽  
pp. C1353-C1360 ◽  
Author(s):  
Satish K. Singh ◽  
Bryan O'Hara ◽  
Jamilur R. Talukder ◽  
Vazhaikkurichi M. Rajendran
Keyword(s):  
Channel Blocker ◽  
Short Circuit ◽  
Distal Colon ◽  
Normal Colonic Mucosa ◽  
Transcriptional Level ◽  
Mrna Levels ◽  
Atpase Inhibitor ◽  
Synthesis Inhibitor ◽  
Rat Distal Colon

Although both Kcnn4c and Kcnma1 channels are present on colonic mucosal membranes, only Kcnma1 has been suggested to mediate K+ secretion in the colon. Therefore, studies were initiated to investigate the relative roles of Kcnn4c and Kcnma1 in mediating aldosterone (Na-free diet)-induced K+ secretion. Mucosal to serosal (m-s), serosal to mucosal (s-m), and net 86Rb+ (K+ surrogate) fluxes as well as short circuit currents ( Isc; measure of net ion movement) were measured under voltage clamp condition in rat distal colon. Active K+ absorption, but not K+ secretion, is present in normal, while aldosterone induces active K+ secretion (1.04 ± 0.26 vs. −1.21 ± 0.15 μeq·h−1·cm−2; P < 0.001) in rat distal colon. Mucosal VO4 (a P-type ATPase inhibitor) inhibited the net K+ absorption in normal, while it significantly enhanced net K+ secretion in aldosterone animals. The aldosterone-induced K+ secretion was inhibited by the mucosal addition of 1) either Ba2+ (a nonspecific K+ channel blocker) or charybdotoxin (CTX; a common Kcnn4 and Kcnma1 channel blocker) by 89%; 2) tetraethyl ammonium (TEA) or iberiotoxin (IbTX; a Kcnma1 channel blocker) by 64%; and 3) TRAM-34 (a Kcnn4 channel blocker) by 29%. TRAM-34, but not TEA, in the presence of IbTX further significantly inhibited the aldosterone-induced K+ secretion. Thus the aldosterone-induced Ba2+/CTX-sensitive K+ secretion consists of IbTX/TEA-sensitive (Kcnma1) and IbTX/TEA-insensitive fractions. TRAM-34 inhibition of the IbTX-insensitive fraction is consistent with the aldosterone-induced K+ secretion being mediated partially via Kcnn4c. Western and quantitative PCR analyses indicated that aldosterone enhanced both Kcnn4c and Kcnma1α protein expression and mRNA abundance. In vitro exposure of isolated normal colonic mucosa to aldosterone also enhanced Kcnn4c and Kcnma1α mRNA levels, and this was prevented by exposure to actinomycin D (an RNA synthesis inhibitor). These observations indicate that aldosterone induces active K+ secretion by enhancing mucosal Kcnn4c and Kcnma1 expression at the transcriptional level.

scholarly journals A52 ANALYSIS AND CHARACTERIZATION OF THE EXCRETED/SECRETED PRODUCTS OF PARASITIC HELMINTHS AS IMMUNOMODULATORS OF INFLAMMATORY BOWEL DISEASE (IBD)

2021 ◽  
Vol 4 (Supplement_1) ◽  
pp. 8-10
Author(s):  
E A Siciliani ◽  
T Arai ◽  
L Leroux ◽  
M M Stevenson ◽  
T G Geary ◽  
...  
Keyword(s):  
Cellular Response ◽  
Immune Modulation ◽  
Mrna Levels ◽  
Engineering Research ◽  
Host Immune Responses ◽  
Parasitic Helminths ◽  
Dss Colitis ◽  
Cytokine Analysis

Abstract Background Parasitic helminths Trichuris suis and Ascaris suum are known to modulate host immune responses. This is thought to be mediated by the secretome, or excreted factors released by these parasites. We are interested in the excretory/secretory products (ESP, TsESP and AsESP) and mechanisms responsible for modulating immune disfunciton in autoinflammatory diseases. Aims This research studies the mechanisms of immune modulation by parasitic helminths in the context of IBD. We aim to describe the cellular response in vitro, as well as the systemic response in vivo, to better characterize the scope of immune modulation in ESP treatment. Methods ESPs were collected from T. suis or A. suum-conditioned media and proteins and metabolites were isolated. Bone marrow (BM) derived macrophages (BMDM) from C57BL6 mice, were treated with ESP fractions, stimulated with LPS, and secreted cytokines levels measured. Alternatively, undifferentiated BM was incubated with or without metabolites throughout the process of differentiation. Using a DSS-colitis model, mice were given 3% DSS or water, then treated with ESP or PBS once daily by IP injection. Colon lengths and TNFα mRNA levels were measured and histological preparations were scored to assess pathology. ESP with bioactivity were selected for further HPLC analysis. Fractions were collected and assayed for bioactivity. Results BMDM treated with T. suis or A. suum crude ESP decreased secretion of TNFα and increased IL-10. BMDM precursors incubated with A. suum metabolites during differentiation had fewer BMDM-like cells. Cytokine analysis showed decreased TNFα secretion. Experiments with Alamar suggested that metabolites remmodelled the BMDM metabolic pathways. These effects are being explored further. We found that metabolites released by A. suum improved DSS-colitis. Specifically, mice with DSS-induced colitis given IP metabolites had reduced colon shortening compared to PBS controls, a lower histologic damage score, as well as lower levels TNFα mRNA expression in gut epithelial cells. HPLC showed multiple peaks from crudes analyzed at 210 nm and 280 nm. HPLC fractions used to treat BMDM yielded varying secretion of TNFα. Bioactive fractions from HPLC coincide with the UV/Vis peaks, further suggesting they could be isolated and studied for immunomodulation. Conclusions These data suggested that ESP contains immunomodulators that may provide lead therapeutic compounds for patients with IBD. Helminth-derived components can immunologically polarize a response in vitro, as well as alter disease recovery in DSS colitis. HPLC fractionation and biological testing suggest that a bioactive molecule can be obtained. Further analysis must be done to determine structure using mass spectrometry and NMR analysis. Funding Agencies Natural Sciences and Engineering Research Council of Canada (NSERC) and Fonds de recherche nature et technologies Québec (FRQNT)

scholarly journals Lipopolysaccharide exposure during the early postnatal period adversely affects the structure and function of the developing rat carotid body

2016 ◽  
Vol 121 (3) ◽  
pp. 816-827 ◽  
Author(s):  
Zankhana R. Master ◽  
Andrea Porzionato ◽  
Kalpashri Kesavan ◽  
Ariel Mason ◽  
Raul Chavez-Valdez ◽  
...  
Keyword(s):  
Premature Infants ◽  
Carotid Body ◽  
Periodic Breathing ◽  
Structure And Function ◽  
Whole Body ◽  
Mrna Levels ◽  
Functional Changes ◽  
And Function ◽  
Developing Rat

The carotid body (CB) substantially influences breathing in premature infants by affecting the frequency of apnea and periodic breathing. In adult animals, inflammation alters the structure and chemosensitivity of the CB, yet it is not known if this pertains to neonates. We hypothesized that early postnatal inflammation leads to morphological and functional changes in the developing rat CB, which persists for 1 wk after the initial provoking insult. To test our hypothesis, we exposed rat pups at postnatal day 2 (P2) to lipopolysaccharide (LPS; 100 μg/kg) or saline (SAL) intraperitoneally. At P9-10 (1 wk after treatment), LPS-exposed animals had significantly more spontaneous intermittent hypoxic (IH) events, attenuated ventilatory responses to changes in oxygen tension (measured by whole body plethysmography), and attenuated hypoxic chemosensitivity of the carotid sinus nerve (measured in vitro), compared with SAL-exposed controls. These functional changes were associated with the following: 1) increased inflammatory cytokine mRNA levels; 2) decreased volume of supportive type II cells; and 3) elevated dopamine levels (a major inhibitory neuromodulator) within the CB. These findings suggest that early postnatal inflammation in newborn rats adversely affects the structure and function of the CB and is associated with increased frequency of intermittent desaturations, similar to the phenomenon observed in premature infants. Furthermore, this is the first newborn model of spontaneous intermittent desaturations that may be used to understand the mechanisms contributing to IH events in newborns.

scholarly journals Anti-inflammatory Effects of Hydrogen in LPS-induced RAW264.7 Cells via Inhibiting NF-κB and MAPKs Signaling Pathways

2021 ◽  
Author(s):  
Tao Zhang ◽  
Fuping Wang ◽  
Guoqiang Jiang ◽  
Guobao Chen ◽  
Lili Han ◽  
...  
Keyword(s):  
Inflammatory Mediators ◽  
Molecular Mechanisms ◽  
Signal Transduction Pathway ◽  
Raw264.7 Cells ◽  
Raw 264.7 Cells ◽  
Mrna Levels ◽  
Rna Seq ◽  
Inflammatory Signaling ◽  
Anti Inflammatory

Abstract Hydrogen (H2), a new type of medical gas molecule, which has significant preventive effect on numerous diseases and its anti-inflammatory properties has been proven in previous studies. However, the mechanisms of H2 anti-inflammatory activity in signal transduction pathway or protein level regulation are inadequately inexplicit. In the current study, the effect of H2 on LPS-induced inflammation in RAW 264.7 cells were assessed and its molecular mechanisms were clarified. The in vitro model of inflammation was induced by lipopolysaccharide (LPS) in RAW264.7 cells. Cell viability was evaluated by MTT assay. Protein expression of inflammatory mediators were analyzed by ELISA and Western blot. mRNA levels were detected by RT-qPCR. In addition, RNA sequencing (RNA-seq) was conducted to explore the molecular targets of H2 anti-inflammatory. According to the findings, H2 reversed LPS-induced variety in NO levels and TNF-a production as well as IL-6, IL-10 proteins and related mRNA levels in macrophages. RNA-seq newly discovered that H2 acted on inflammatory signaling molecule protein kinase C 8 (PKC8) and heterodimer activator protein-1 (AP-1). The WB analysis was then used to determine the key proteins in the inflammatory signaling pathway involved in PKC8 and AP-1, which found that H2 inhibited the phosphorylation of key proteins in the NF-kB and MAPKs pathways, thereby the expression of mRNA and inflammatory mediators were affected. The findings of this study show that H2 may serve as a promising anti-inflammatory gas in mitigating inflammatory conditions.

scholarly journals Bu-Zhong-Yi-Qi Granule Enhances Colonic Tight Junction Integrity via TLR4/NF-κB/MLCK Signaling Pathway in Ulcerative Colitis Rats

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Xiuhong Kang ◽  
Mengdi Jia ◽  
Luqing Zhao ◽  
Shengsheng Zhang
Keyword(s):  
Ulcerative Colitis ◽  
Tight Junction ◽  
Western Blot ◽  
Activity Index ◽  
Damage Index ◽  
Interleukin 10 ◽  
Trinitrobenzene Sulfonic Acid ◽  
Therapeutic Effects ◽  
Mrna Levels ◽  
Tnf Α

Background. Bu-zhong-yi-qi granule (BZYQ), a sort of Chinese herbal medicine, has exhibited therapeutic effects on ulcerative colitis (UC). However, the mechanism of BZYQ has not been fully clarified. This study was aimed at investigating the effects of BZYQ on UC rats model and at exploring its potential mechanism. Methods. The UC rats were established by enema of trinitrobenzene sulfonic acid (TNBS). The therapeutic effects of BZYQ treatment were evaluated by disease activity index (DAI), colon macroscopic damage index (CMDI) scores, and histological observation. The mRNA levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-10 (IL-10) were measured by quantitative real time-polymerase chain reaction (qPCR). The expression of tight junction (TJ) proteins, occludin and claudin-1, in the colon was determined by Western blot and immunofluorescence. The expression of toll-like receptors 4 (TLR4), nuclear factor-kappa B (NF-κB), p-NF-κB, myosin light chain kinase (MLCK), MLC, and p-MLC levels in colon was determined by Western blot or qPCR. Results. The results showed that BZYQ could attenuate DAI, CMDI, and histological inflammation. TJ proteins expression was decreased in UC rats, but treatment with BZYQ restored the expression of occludin and claudin-1. In addition, BZYQ administration ameliorated UC-associated increase in the production of TNF-α, IL-1β, and the expression of TLR4, NF-κB, p-NF-κB, MLCK, MLC, and p-MLC, while BZYQ administration increased the production of IL-10. Conclusions. The therapeutic effect of BZYQ on UC is at least partially through regulation of the secretion of some inflammatory cytokines and improvement of TJ integrity via TLR4/NF-κB/MLCK pathway.

Nanocurcumin: A Double-Edged Sword for Microcancers

2020 ◽  
Vol 26 (45) ◽  
pp. 5783-5792
Author(s):  
Kholood Abid Janjua ◽  
Adeeb Shehzad ◽  
Raheem Shahzad ◽  
Salman Ul Islam ◽  
Mazhar Ul Islam
Keyword(s):  
Intracellular Signaling ◽  
Dosage Forms ◽  
The Body ◽  
In Vivo Studies ◽  
Mrna Levels ◽  
Anticancer Activities ◽  
Road Map ◽  
Anticancer Effects

There is compelling evidence that drug molecules isolated from natural sources are hindered by low systemic bioavailability, poor absorption, and rapid elimination from the human body. Novel approaches are urgently needed that could enhance the retention time as well as the efficacy of natural products in the body. Among the various adopted approaches to meet this ever-increasing demand, nanoformulations show the most fascinating way of improving the bioavailability of dietary phytochemicals through modifying their pharmacokinetics and pharmacodynamics. Curcumin, a yellowish pigment isolated from dried ground rhizomes of turmeric, exhibits tremendous pharmacological effects, including anticancer activities. Several in vitro and in vivo studies have shown that curcumin mediates anticancer effects through the modulation (upregulation and/or downregulations) of several intracellular signaling pathways both at protein and mRNA levels. Scientists have introduced multiple modern techniques and novel dosage forms for enhancing the delivery, bioavailability, and efficacy of curcumin in the treatment of various malignancies. These novel dosage forms include nanoparticles, liposomes, micelles, phospholipids, and curcumin-encapsulated polymer nanoparticles. Nanocurcumin has shown improved anticancer effects compared to conventional curcumin formulations. This review discusses the underlying molecular mechanism of various nanoformulations of curcumin for the treatment of different cancers. We hope that this study will make a road map for preclinical and clinical investigations of cancer and recommend nano curcumin as a drug of choice for cancer therapy.

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