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Pharmacological Research Sep 2023In our previous multicenter study, we delineated the inherent metabolic features of colorectal cancer (CRC). Therein, we identified a member of the ectonucleotide...
In our previous multicenter study, we delineated the inherent metabolic features of colorectal cancer (CRC). Therein, we identified a member of the ectonucleotide pyrophosphatase/ phosphodiesterase family (ENPP2) as a significant differential metabolite of CRC. In this study, the role of ENPP2 in CRC has been demonstrated using established in vitro and in vivo models including ENPP2 gene knockdown, and use of the ENPP2 inhibitor, GLPG1690. We found that CRC proliferation was decreased after either ENPP2 gene knockdown or use of ENPP2 inhibitors. We further evaluated the role of GLPG1690 in AOM/DSS-induced CRC mice via intestinal barrier function, macrophage polarization, inflammatory response and microbial homeostasis. Results of immunofluorescence staining and Western blotting showed that GLPG1690 can restore gut-barrier function by increasing the expression of tight junction proteins, claudin-1, occludin and ZO-1. M2 tumor-associated macrophage polarization and colonic inflammation were attenuated after treatment with GLPG1690 using the Azoxymethane/Dextran Sodium Sulfate (AOM/DSS) model. Moreover, 16 S rDNA pyrosequencing and metagenomic analysis showed that GLPG1690 could alleviate gut dysbiosis in mice. Furthermore, administration of GLPG1690 with antibiotics as well as fecal microbiota transplantation assays demonstrated a close link between the efficacy of GLPG1690 and the gut microbiota composition. Finally, results of metabolomic analysis implicated mainly the gut microbiota-derived metabolites of aromatic amino acids in CRC progression. These findings may provide novel insights into the development of small-molecule ENPP2 inhibitors for the treatment of CRC.
Topics: Animals; Mice; Azoxymethane; Cell Proliferation; Colitis; Colorectal Neoplasms; Dextran Sulfate; Disease Models, Animal; Gastrointestinal Microbiome; Mice, Inbred C57BL; Phosphoric Diester Hydrolases
PubMed: 37524154
DOI: 10.1016/j.phrs.2023.106877 -
BMC Cancer Mar 2016Alcohol consumption is one of the major risk factors for colorectal cancer. However, the mechanism involved in this effect of alcohol is unknown.
BACKGROUND
Alcohol consumption is one of the major risk factors for colorectal cancer. However, the mechanism involved in this effect of alcohol is unknown.
METHODS
We evaluated the effect of chronic ethanol feeding on azoxymethane and dextran sulfate sodium (AOM/DSS)-induced carcinogenesis in mouse colon. Inflammation in colonic mucosa was assessed at a precancerous stage by evaluating mucosal infiltration of neutrophils and macrophages, and analysis of cytokine and chemokine gene expression.
RESULTS
Chronic ethanol feeding significantly increased the number and size of polyps in colon of AOM/DSS treated mice. Confocal microscopic and immunoblot analyses showed a significant elevation of phospho-Smad, VEGF and HIF1α in the colonic mucosa. RT-PCR analysis at a precancerous stage indicated that ethanol significantly increases the expression of cytokines IL-1α, IL-6 and TNFα, and the chemokines CCL5/RANTES, CXCL9/MIG and CXCL10/IP-10 in the colonic mucosa of AOM/DSS treated mice. Confocal microscopy showed that ethanol feeding induces a dramatic elevation of myeloperoxidase, Gr1 and CD68-positive cells in the colonic mucosa of AOM/DSS-treated mice. Ethanol feeding enhanced AOM/DSS-induced suppression of tight junction protein expression and elevated cell proliferation marker, Ki-67 in the colonic epithelium.
CONCLUSION
This study demonstrates that chronic ethanol feeding promotes colonic tumorigenesis potentially by enhancing inflammation and elevation of proinflammatory cytokines and chemokines.
Topics: Animals; Azoxymethane; Biomarkers, Tumor; Cell Proliferation; Cell Transformation, Neoplastic; Chemokines; Colonic Neoplasms; Cytokines; Dextran Sulfate; Ethanol; Female; Gene Expression; Inflammation; Intestinal Mucosa; Mice; Protein Transport
PubMed: 26951793
DOI: 10.1186/s12885-016-2180-x -
Trends in Neurosciences Mar 2015Elevated dopamine function and alterations in medial temporal lobe (MTL) structure and function are two of the most robust findings in schizophrenia, but how... (Review)
Review
Elevated dopamine function and alterations in medial temporal lobe (MTL) structure and function are two of the most robust findings in schizophrenia, but how interactions between these abnormalities underlie the onset of psychosis is unclear. The methylazoxymethanol acetate (MAM) rodent model proposes that psychosis develops as a result of a perturbation of MTL function, leading to elevated striatal dopamine dysfunction. Here, we review several recent neuroimaging studies that examine components of the putative model in humans with an ultra high risk (UHR) of the psychosis. While data from these studies are broadly consistent with the MAM model, caution is required when comparing data across animal and human studies.
Topics: Animals; Brain; Disease Models, Animal; Humans; Methylazoxymethanol Acetate; Psychotic Disorders
PubMed: 25554679
DOI: 10.1016/j.tins.2014.12.005 -
Biochimica Et Biophysica Acta.... Jan 2022GPR65 (TDAG8) is a proton-sensing G protein-coupled receptor predominantly expressed in immune cells. Genome-wide association studies (GWAS) have identified GPR65 gene...
GPR65 (TDAG8) is a proton-sensing G protein-coupled receptor predominantly expressed in immune cells. Genome-wide association studies (GWAS) have identified GPR65 gene polymorphisms as an emerging risk factor for the development of inflammatory bowel disease (IBD). Patients with IBD have an elevated risk of developing colorectal cancer when compared to the general population. To study the role of GPR65 in intestinal inflammation and colitis-associated colorectal cancer (CAC), colitis and CAC were induced in GPR65 knockout (KO) and wild-type (WT) mice using dextran sulfate sodium (DSS) and azoxymethane (AOM)/DSS, respectively. Disease severity parameters such as fecal score, colon shortening, histopathology, and mesenteric lymph node enlargement were aggravated in GPR65 KO mice compared to WT mice treated with DSS. Elevated leukocyte infiltration and fibrosis were observed in the inflamed colon of GPR65 KO when compared to WT mice which may represent a cellular mechanism for the observed exacerbation of intestinal inflammation. In line with high expression of GPR65 in infiltrated leukocytes, GPR65 gene expression was increased in inflamed intestinal tissue samples of IBD patients compared to normal intestinal tissues. Moreover, colitis-associated colorectal cancer development was higher in GPR65 KO mice than WT mice when treated with AOM/DSS. Altogether, our data demonstrate that GPR65 suppresses intestinal inflammation and colitis-associated tumor development in murine colitis and CAC models, suggesting potentiation of GPR65 with agonists may have an anti-inflammatory therapeutic effect in IBD and reduce the risk of developing colitis-associated colorectal cancer.
Topics: Animals; Azoxymethane; Colitis; Colitis-Associated Neoplasms; Colon; Dextran Sulfate; Disease Models, Animal; Fibrosis; Gene Expression Regulation; Humans; Inflammation; Inflammatory Bowel Diseases; Leukocytes; Mice; Mice, Knockout; Receptors, G-Protein-Coupled; Severity of Illness Index
PubMed: 34628032
DOI: 10.1016/j.bbadis.2021.166288 -
Environmental and Molecular Mutagenesis Mar 2016Considerable evidence suggests that environmental factors, including diet and cigarette smoke, are involved in the pathogenesis of colon cancer. Carcinogenic nitroso... (Comparative Study)
Comparative Study
Comparative DNA adduct formation and induction of colonic aberrant crypt foci in mice exposed to 2-amino-9H-pyrido[2,3-b]indole, 2-amino-3,4-dimethylimidazo[4,5-f]quinoline, and azoxymethane.
Considerable evidence suggests that environmental factors, including diet and cigarette smoke, are involved in the pathogenesis of colon cancer. Carcinogenic nitroso compounds (NOC), such as N-nitrosodimethylamine (NDMA), are present in tobacco and processed red meat, and NOC have been implicated in colon cancer. Azoxymethane (AOM), commonly used for experimental colon carcinogenesis, is an isomer of NDMA, and it produces the same DNA adducts as does NDMA. Heterocyclic aromatic amines (HAAs) formed during the combustion of tobacco and high-temperature cooking of meats are also associated with an elevated risk of colon cancer. The most abundant carcinogenic HAA formed in tobacco smoke is 2-amino-9H-pyrido[2,3-b]indole (AαC), whereas 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) is the most potent carcinogenic HAA formed during the cooking of meat and fish. However, the comparative tumor-initiating potential of AαC, MeIQ, and AOM is unknown. In this report, we evaluate the formation of DNA adducts as a measure of genotoxicity, and the induction of colonic aberrant crypt foci (ACF) and dysplastic ACF, as an early measure of carcinogenic potency of these compounds in the colon of male A/J mice. Both AαC and AOM induced a greater number of DNA adducts than MeIQ in the liver and colon. AOM induced a greater number of ACF and dysplastic ACF than either AαC or MeIQ. Conversely, based on adduct levels, MeIQ-DNA adducts were more potent than AαC- and AOM-DNA adducts at inducing ACF. Long-term feeding studies are required to relate levels of DNA adducts, induction of ACF, and colon cancer by these colon genotoxicants.
Topics: Animals; Azoxymethane; Body Weight; Carcinogens; Colon; DNA Adducts; Liver; Male; Mice, Inbred Strains; Mucins; Quinolines; Toxicity Tests, Subchronic
PubMed: 26734915
DOI: 10.1002/em.21993 -
Azoxymethane-induced rat aberrant crypt foci: relevance in studying chemoprevention of colon cancer.World Journal of Gastroenterology Nov 2008The pathogenesis of colon cancer involves sequential and multistep progression of epithelial cells initiated to a cancerous state with defined precancerous... (Review)
Review
The pathogenesis of colon cancer involves sequential and multistep progression of epithelial cells initiated to a cancerous state with defined precancerous intermediaries. Aberrant crypt foci (ACF) represent the earliest identifiable intermediate precancerous lesions during colon carcinogenesis in both laboratory animals and humans. ACF are easily induced by colon-specific carcinogens in rodents and can be used to learn more about the process of colon carcinogenesis. For over two decades, since its first discovery, azoxymethane (AOM)-induced rodent ACF have served as surrogate biomarkers in the screening of various anticarcinogens and carcinogens. Several dietary constituents and phytochemicals have been tested for their colon cancer chemopreventive efficacy using the ACF system. There has been substantial effort in defining and refining ACF in terms of understanding their molecular make-up, and extensive research in this field is currently in progress. In chemoprevention studies, AOM-induced rat ACF have been very successful as biomarkers, and have provided several standardized analyses of data. There have been several studies that have reported that ACF data do not correlate to actual colon tumor outcome, however, and hence there has been an ambiguity about their role as biomarkers. The scope of this mini-review is to provide valuable insights and limitations of AOM-induced rat ACF as biomarkers in colon cancer chemoprevention studies. The role of the dynamics and biological heterogeneity of ACF is critical in understanding them as biomarkers in chemoprevention studies.
Topics: Animals; Azoxymethane; Biomarkers, Tumor; Carcinogens; Chemoprevention; Colon; Colonic Neoplasms; Disease Models, Animal; Humans; Precancerous Conditions; Rats
PubMed: 19034964
DOI: 10.3748/wjg.14.6632 -
Nutrients Mar 2023Defatted rice bran (DRB) is a by-product of rice bran derived after the oil extraction. DRB contains several bioactive compounds, including dietary fiber and...
Defatted rice bran (DRB) is a by-product of rice bran derived after the oil extraction. DRB contains several bioactive compounds, including dietary fiber and phytochemicals. The supplementation with DRB manifests chemopreventive effects in terms of anti-chronic inflammation, anti-cell proliferation, and anti-tumorigenesis in the azoxymethane (AOM) and dextran sodium sulfate (DSS)-induced colitis-associated colorectal cancer (CRC) model in rats. However, little is known about its effect on gut microbiota. Herein, we investigated the effect of DRB on gut microbiota and short chain fatty acid (SCFA) production, colonic goblet cell loss, and mucus layer thickness in the AOM/DSS-induced colitis-associated CRC rat model. The results suggested that DRB enhanced the production of beneficial bacteria (, , , , ) and lessened the production of harmful bacteria (, , , ) present in colonic feces, mucosa, and tumors. In addition, DRB also assisted the cecal SCFAs (acetate, propionate, butyrate) production. Furthermore, DRB restored goblet cell loss and improved the thickness of the mucus layer in colonic tissue. These findings suggested that DRB could be used as a prebiotic supplement to modulate gut microbiota dysbiosis, which decreases the risks of CRC, therefore encouraging further research on the utilization of DRB in various nutritional health products to promote the health-beneficial bacteria in the colon.
Topics: Rats; Animals; Mice; Colitis; Oryza; Colitis-Associated Neoplasms; Gastrointestinal Microbiome; Azoxymethane; Colon; Bacteria; Bacteroidetes; Dextran Sulfate; Disease Models, Animal; Mice, Inbred C57BL
PubMed: 36986258
DOI: 10.3390/nu15061528 -
Journal of Ethnopharmacology May 2024Inflammatory bowel disease (IBD) presents a risk of carcinogenesis, which escalates with the duration of IBD. Persistent histological inflammation is considered to be...
Anchang Yuyang Decoction inhibits experimental colitis-related carcinogenesis by regulating PPAR signaling pathway and affecting metabolic homeostasis of host and microbiota.
ETHNOPHARMACOLOGICAL RELEVANCE
Inflammatory bowel disease (IBD) presents a risk of carcinogenesis, which escalates with the duration of IBD. Persistent histological inflammation is considered to be the driving factor of colitis carcinogenesis. Effective control of inflammation is helpful to prevent and treat colitis-related colorectal cancer (CAC). Anchang Yuyang Decoction (AYD), a traditional Chinese medicine (TCM) formula, is originated from the ancient prescription of TCM for treating colitis and colorectal cancer. AYD has demonstrated efficacy in treating IBD and potential anti-carcinogenic properties.
AIM OF THE STUDY
This research aims to assess the therapeutic efficacy of AYD in ameliorating experimental colitis-related carcinogenesis induced by AOM/DSS. It further seeks to elucidate its potential mechanisms by integrating multiple omics sequencing approaches.
MATERIALS AND METHODS
A rat model for colitis-related carcinogenesis was developed using azoxymethane (AOM)/dextran sulfate sodium (DSS). UPLC-MS identified AYD's chemical constituents. Rats were administered varying doses of AYD (18.37, 9.19 and 4.59 g/kg) orally for 53 days, with mesalazine as a positive control. The study evaluated anti-carcinogenic effects by examining adenoma number, adenoma load, abnormal crypt foci (ACF), histopathological damage, and tumor-related protein expression. Anti-inflammatory and reparative effects were assessed through body weight, disease activity index (DAI), colon length, spleen index, inflammatory cytokine levels, and tight junction protein expression. The effects on intestinal microbiota and host metabolism were explored through 16S rRNA sequencing, targeted short-chain fatty acid (SCFA) metabonomics, and non-targeted colon metabolomics. Potential AYD targets were identified through transcriptomic sequencing and validated by qRT-PCR and western blotting.
RESULTS
AYD significantly reduced adenoma number, adenoma load, neoplasm-associated lesions, ACF, and tumor-related protein expression (e.g., p53, PCNA) in AOM/DSS-induced rats, thus impeding colitis-related carcinogenesis progression. AYD also alleviated histopathological damage and inflammation, promoting intestinal mucosal barrier repair. Furthermore, AYD modulated intestinal flora structure, enhanced SCFA production, and regulated colon metabolites. Transcriptomic sequencing revealed a significant impact on the peroxisome proliferator-activated receptor (PPAR) signaling pathway. Subsequent qRT-PCR and western blotting experiments indicated AYD's influence in up-regulating PPAR-γ and down-regulating PPAR-α, PPAR-β/δ, and related proteins (thrombomodulin [Thbd], fatty acid binding protein 5 [Fabp5], stearoyl-CoA desaturase 2 [Scd2], phospholipid transfer protein [Pltp]).
CONCLUSIONS
This study demonstrates AYD's ability to inhibit experimental colitis-related carcinogenesis induced by AOM/DSS. Its mechanism likely involves modulation of the PPAR signaling pathway, impacting intestinal microbiota and host metabolic equilibrium.
Topics: Rats; Animals; Mice; Peroxisome Proliferator-Activated Receptors; RNA, Ribosomal, 16S; Chromatography, Liquid; Tandem Mass Spectrometry; Colitis; Inflammation; Signal Transduction; Inflammatory Bowel Diseases; Carcinogenesis; Azoxymethane; Gastrointestinal Microbiome; Colorectal Neoplasms; Homeostasis; Adenoma; Dextran Sulfate; Disease Models, Animal; Mice, Inbred C57BL; Colon
PubMed: 38428656
DOI: 10.1016/j.jep.2024.117995 -
The Journal of Nutrition Dec 2005Observational epidemiology supports the hypothesis that variation in diet and other lifestyle exposures accounts for a large part of the variation in incidence of... (Review)
Review
Observational epidemiology supports the hypothesis that variation in diet and other lifestyle exposures accounts for a large part of the variation in incidence of colorectal cancer (CRC). Physical inactivity is associated strongly with enhanced CRC risk, but no human intervention studies have shown causality. This paper reviews data from all available studies of the effects of exercise interventions on intestinal neoplasia using rat and mouse models. All 5 published studies of effects of increased physical activity (both forced and voluntary) using carcinogen-treated rat models show strong protection against CRC by greater physical activity. In contrast, there is little convincing evidence of reduced intestinal neoplasia after increased physical activity in the 3 published studies using Apc(Min) mice (which develop multiple intestinal polyps spontaneously) although the nature and amounts of physical activity imposed in rats and mice were similar. Major differences in protocol between the 2 groups of studies are that the rat studies were much longer (at least 20 wk and in most cases 38 wk compared with < or =9 wk for the mouse studies) and the primary endpoint was colorectal carcinoma (rats) rather than small bowel adenomas (mice). The epidemiological evidence for protection against adenoma formation by increased physical activity is weaker than that for carcinoma. The limited evidence available suggests that, compared with rats, mice may show a greater compensation for energy expenditure in exercise through reduction in nonexercise physical activity, thus ameliorating effects. The resulting smaller effects on body weight and body fatness may limit changes in intestinal neoplasia in Apc(Min) mice.
Topics: 1,2-Dimethylhydrazine; Animals; Azoxymethane; Body Mass Index; Body Weight; Carcinogens; Colorectal Neoplasms; Diet; Male; Mice; Motor Activity; Rats; Rats, Inbred F344; Rats, Sprague-Dawley
PubMed: 16317161
DOI: 10.1093/jn/135.12.3002S -
Yakugaku Zasshi : Journal of the... 2024Zinc is one of the essential trace elements, and is involved in various functions in the body. Zinc deficiency is known to cause immune abnormalities, but the mechanism... (Review)
Review
Zinc is one of the essential trace elements, and is involved in various functions in the body. Zinc deficiency is known to cause immune abnormalities, but the mechanism is not fully understood. Therefore, we focused our research on tumor immunity to elucidate the effect of zinc on colorectal cancer and its mechanisms. Mice were treated with azoxymethane (AOM) and dextran sodium sulfate (DSS) to develop colorectal cancer, then the relationship between zinc content in the diet and the number and area of tumors in the colon was observed. The number of tumors in the colon was significantly higher in the no-zinc-added diet group compared to the normal zinc intake group, and about half the number in the high-zinc-intake group compared to the normal-zinc-intake group. In T-cell-deficient mice, the number of tumors in the high-zinc-intake group was similar to that in the normal-zinc-intake group, suggesting that the inhibitory effect of zinc was dependent on T cells. Furthermore, we found that the amount of granzyme B transcript released by cytotoxic T cells upon antigen stimulation was significantly increased by the addition of zinc. We also showed that granzyme B transcriptional activation by zinc addition was dependent on calcineurin activity. Collectively, we have shown that zinc exerts its tumor-suppressive effect by acting on cytotoxic T cells, the center of cellular immunity, and that it increases the transcription of granzyme B, one of the key molecules involved in tumor immunity. In this symposium, we would like to introduce our latest data on the relationship between zinc and tumor immunity.
Topics: Animals; Colorectal Neoplasms; Zinc; Mice; Immunity, Cellular; Humans; Granzymes; T-Lymphocytes, Cytotoxic; Azoxymethane; Disease Models, Animal
PubMed: 38692920
DOI: 10.1248/yakushi.23-00154-1