Search results for "Azoxymethane"
showing 8 items of 8 documents
Chemopreventive effect of oleuropein in colitis-associated colorectal cancer in c57bl/6 mice
2015
Scope The main phenolic secoiridoid oleuropein and active constituent from olive tree (Olea europaea, Oleaceae), has demonstrated anti-inflammatory properties in intestinal inflammation and anti-tumoral effects in different cancer cells. In this study, we evaluated the chemoprevention of oleuropein in a model of azoxymethane (AOM)/Dextran sulfate sodium (DSS)-induced colorectal cancer (CRC) in C57BL/6 mice and the modulatory effect on the Th17 response in DSS acute colitis. Methods and results Oleuropein protected from AOM/DSS-induced CRC by improving clinical symptoms, disease activity index score as well as suppressed the growth and multiplicity of colonic tumors. Treatment with oleuropei…
Shikonin Prevents Early Phase Inflammation Associated with Azoxymethane/Dextran Sulfate Sodium-Induced Colon Cancer and Induces Apoptosis in Human Co…
2018
Shikonin is the main active principle in the root of Lithospermum erythrorhizon, widely used in traditional Chinese medicine for its anti-inflammatory and wound healing properties. Recent research highlights shikonin's antitumor properties and capacity to prevent acute ulcerative colitis. The aim of the present study was to evaluate the ability of shikonin to prevent, in vivo, the early phases of colorectal cancer development, with special focus on its cytotoxic mechanism in vitro. We employed the azoxymethane/dextran sulfate sodium model of colitis in Balb/C mice. Body weight and drinking were monitored throughout the experiment, and length of colon and lesions of the colon were recorded o…
Mast Cells Infiltrating Inflamed or Transformed Gut Alternatively Sustain Mucosal Healing or Tumor Growth.
2015
Abstract Mast cells (MC) are immune cells located next to the intestinal epithelium with regulatory function in maintaining the homeostasis of the mucosal barrier. We have investigated MC activities in colon inflammation and cancer in mice either wild-type (WT) or MC-deficient (KitW-sh) reconstituted or not with bone marrow-derived MCs. Colitis was chemically induced with dextran sodium sulfate (DSS). Tumors were induced by administering azoxymethane (AOM) intraperitoneally before DSS. Following DSS withdrawal, KitW-sh mice showed reduced weight gain and impaired tissue repair compared with their WT littermates or KitW-sh mice reconstituted with bone marrow-derived MCs. MCs were localized i…
Increased endocannabinoid levels reduce the development of precancerous lesions in the mouse colon
2007
Colorectal cancer is an increasingly important cause of death in Western countries. Endocannabinoids inhibit colorectal carcinoma cell proliferation in vitro. In this paper, we investigated the involvement of endocannabinoids on the formation of aberrant crypt foci (ACF, earliest preneoplastic lesions) in the colon mouse in vivo. ACF were induced by azoxymethane (AOM); fatty acid amide hydrolase (FAAH) and cannabinoid receptor messenger ribonucleic acid (mRNA) levels were analyzed by the quantitative reverse transcription polymerase chain reaction (RT-PCR); endocannabinoid levels were measured by liquid chromatography-mass spectrometry; caspase-3 and caspase-9 expressions were measured by W…
An inducible mouse model of colon carcinogenesis for the analysis of sporadic and inflammation-driven tumor progression.
2007
Colorectal cancer is a life-threatening disease that can develop spontaneously or as a complication of inflammatory bowel diseases. Mouse models are essential tools for the preclinical testing of novel therapeutic options in vivo. Here, we provide a highly reliable protocol for an experimental mouse model to study the development of colon cancers. It is based on the mutagenic agent azoxymethane (AOM), which exerts colonotropic carcinogenicity. Repeated intraperitoneal administration of AOM results in the development of spontaneous tumors within 30 weeks. As an alternative option, inflammation-dependent tumor growth can be investigated by combining the administration of AOM with the inflamma…
A variant of Smurf2 protects mice against colitis-associated colon cancer by inducing transforming growth factor β signaling.
2011
Background & Aims Transforming growth factor (TGF)-β signaling, which is down-regulated by the E3 ubiquitin ligase Smad ubiquitin regulating factor 2 (Smurf2), promotes development of cancer. We identified a splice variant of Smurf2 (ΔE2Smurf2) and investigated its role in colon carcinogenesis in mice. Methods Colitis-associated colon cancer was induced in mice by administration of azoxymethane, followed by 3 cycles of oral administration of dextran sodium sulfate. Messenger RNA levels of Smurf2 in colon tumors and control tissue were measured by quantitative polymerase chain reaction; lymphocyte and cytokine levels were measured in tumor and tissue samples. Results Tumor-infiltrating CD4 +…
Stool Phospholipid Signature is Altered by Diet and Tumors
2014
Intake of saturated fat is a risk factor for ulcerative colitis (UC) and colon cancer. Changes in the microbiota have been implicated in the development of UC and colon cancer. The host and the microbiota generate metabolites that may contribute to or reflect disease pathogenesis. We used lipid class specific quantitative mass spectrometry to assess the phospholipid (PL) profile (phosphatidylcholine [PC], phosphatidylethanolamine [PE], phosphatidylinositol [PI], phosphatidylserine [PS]) of stool from mice fed a high fat (HFD) or control diet with or without induction of colitis-associated tumors using azoxymethane and dextran sodium sulfate. The microbiota was assessed using qPCR for severa…
In vivo imaging of colitis and colon cancer development in mice using high resolution chromoendoscopy
2005
Background: Mouse models of colitis and cancer are indispensable for our understanding of the pathogenesis of these diseases. In the past, mice had to be sacrificed in order to analyse colitis activity and tumour development. We have developed a safe method for high resolution endoscopic monitoring of living mice. Methods: Mice developing colitis or colonic tumours were anaesthetised using avertine and repeatedly examined by endoscopy. A novel miniendoscope (1.9 mm outer diameter), denoted Coloview, was introduced via the anus and the colon was carefully insufflated with an air pump before analysis of the colonic mucosa. An extra working channel allowed the introduction of biopsy forceps or…