Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 7 de 7
Filter
1.
BMC Gastroenterol ; 16(1): 133, 2016 Oct 13.
Article in English | MEDLINE | ID: mdl-27737636

ABSTRACT

BACKGROUND: Adequate bowel preparation is an essential prerequisite for complete mucosal visualization during colonoscopy. Polyethylene glycol (PEG) solutions are commonly used. However the large volume of the solution is often poorly tolerated. Addition of Lubiprostone (LB) could improve the adequacy of standard PEG preparation & reduce requirement. The aims to assess adequacy of PEG preparation with addition of single dose LB (24mcg) vs placebo and efficacy of reduced dose PEG + LB compared with full dose PEG + LB. METHODS: Single center prospective double blind randomized controlled trial. Part I: 442 patients for colonoscopy randomized to receive placebo (GrA) or single dose of LB (GrB) prior to PEG preparation. Quality of bowel preparation graded 0-9 according to Boston Bowel Preparation Scale (BBPS). BBPS-9: excellent and BBPS 0-4: repeat procedure. Part II: 146 patients randomized to receive LB + 1.5 L PEG (GrC; 75) or LB + 1 L PEG (GrD; 71). BBPS score compared with GrB (2 L PEG). RESULTS: Part I: 442 patients (221 GrA & 221 Gr B). LB resulted in significant improvement in total BBPS (7.44 + 0.14 vs. 6.36 + 0.16, p < 0.0001). 66.5 % Gr B vs 38 % Gr A had excellent prep; 42.5 % GrB vs 24 % GrA had adequate prep. Repeat procedure needed 9.5 % Gr B vs 16.7 % Gr A (P < 0.01). Part II: No difference in BBPS scores with lower doses (Gr C&D) compared to standard (GrB) (Mean BBPS 7.44 + 0.14 GrA,7.30 + 0.25 GrC;7.25 + 0.26 GrD;p >0.05). CONCLUSION: Single dose LB prior to PEG significantly enhanced bowel preparation compared to PEG alone. There was no significant difference in quality of preparation with lower doses of PEG when combined with LB. TRIAL REGISTRATION: The study protocol was approved by institutional review board and the trial was registered on March 22, 2011 with clinicaltrials.gov ( NCT01324284 ).


Subject(s)
Cathartics/administration & dosage , Colonoscopy , Lubiprostone/administration & dosage , Polyethylene Glycols/administration & dosage , Preoperative Care/methods , Adult , Double-Blind Method , Drug Therapy, Combination , Female , Humans , Male , Middle Aged , Prospective Studies , Treatment Outcome
2.
Sci Rep ; 5: 14110, 2015 Sep 16.
Article in English | MEDLINE | ID: mdl-26374068

ABSTRACT

Cholinergic nervous system regulates liver injury. However, the role of M1 muscarinic receptors (M1R) in modulating chronic liver injury is uncertain. To address this gap in knowledge we treated M1R-deficient and WT mice with azoxymethane (AOM) for six weeks and assessed liver injury responses 14 weeks after the last dose of AOM. Compared to AOM-treated WT mice, M1R-deficient mice had attenuated liver nodularity, fibrosis and ductular proliferation, α-SMA staining, and expression of α1 collagen, Tgfß-R, Pdgf-R, Mmp-2, Timp-1 and Timp-2. In hepatocytes, these findings were associated with reductions of cleaved caspase-3 staining and Tnf-α expression. In response to AOM treatment, M1R-deficient mice mounted a vigorous anti-oxidant response by upregulating Gclc and Nqo1 expression, and attenuating peroxynitrite generation. M1R-deficient mouse livers had increased expression of Trail-R2, a promotor of stellate cell apoptosis; dual staining for TUNNEL and α-SMA revealed increased stellate cells apoptosis in livers from M1R-deficient mice compared to those from WT. Finally, pharmacological inhibition of M1R reduced H2O2-induced hepatocyte apoptosis in vitro. These results indicate that following liver injury, anti-oxidant response in M1R-deficient mice attenuates hepatocyte apoptosis and reduces stellate cell activation, thereby diminishing fibrosis. Therefore, targeting M1R expression and activation in chronic liver injury may provide therapeutic benefit.


Subject(s)
Azoxymethane/adverse effects , Liver Diseases/etiology , Receptor, Muscarinic M1/deficiency , Acute Disease , Animals , Apoptosis/genetics , Bile Ducts/metabolism , Bile Ducts/pathology , Cell Survival/genetics , Disease Models, Animal , Fibrosis , Hepatic Stellate Cells/drug effects , Hepatic Stellate Cells/metabolism , Hepatocytes/metabolism , Hepatocytes/pathology , Hyperplasia , Liver Diseases/metabolism , Liver Diseases/pathology , Matrix Metalloproteinases/genetics , Matrix Metalloproteinases/metabolism , Mice , Mice, Knockout , Oxidative Stress , Receptor, Muscarinic M1/genetics , Receptor, Muscarinic M1/metabolism , Tissue Inhibitor of Metalloproteinases/genetics , Tissue Inhibitor of Metalloproteinases/metabolism
3.
Mol Cancer ; 13: 77, 2014 Apr 03.
Article in English | MEDLINE | ID: mdl-24694019

ABSTRACT

BACKGROUND: M3 and M1 subtype muscarinic receptors are co-expressed in normal and neoplastic intestinal epithelial cells. In mice, ablating Chrm3, the gene encoding M3R, robustly attenuates intestinal tumor formation. Here we investigated the effects of Chrm1 gene ablation, alone and in combination with Chrm3 ablation. METHODS: We used wild-type, Chrm1-/-, Chrm3-/- and combined Chrm1-/-/Chrm3-/- knockout (dual knockout) mice. Animals were treated with azoxymethane, an intestine-selective carcinogen. After 20 weeks, colon tumors were counted and analyzed histologically and by immunohistochemical staining. Tumor gene expression was analyzed using microarray and results validated by RT-PCR. Key findings were extended by analyzing gene and protein expression in human colon cancers and adjacent normal colon tissue. RESULTS: Azoxymethane-treated Chrm3-/- mice had fewer and smaller colon tumors than wild-type mice. Reductions in colon tumor number and size were not observed in Chrm1-/- or dual knockout mice. To gain genetic insight into these divergent phenotypes we used an unbiased microarray approach to compare gene expression in tumors from Chrm3-/- to those in wild-type mice. We detected altered expression of 430 genes, validated by quantitative RT-PCR for the top 14 up- and 14 down-regulated genes. Comparing expression of this 28-gene subset in tumors from wild-type, Chrm3-/-, Chrm1-/- and dual knockout mice revealed significantly reduced expression of Zfp277, encoding zinc finger protein 277, in tissue from M3R-deficient and dual knockout mice, and parallel changes in Zfp277 protein expression. Notably, mRNA and protein for ZNF277, the human analogue of Zfp277, were increased in human colon cancer compared to adjacent normal colon, along with parallel changes in expression of M3R. CONCLUSIONS: Our results identify a novel candidate mouse gene, Zfp277, whose expression pattern is compatible with a role in mediating divergent effects of Chrm3 and Chrm1 gene ablation on murine intestinal neoplasia. The biological importance of this observation is strengthened by finding increased expression of ZNF277 in human colon cancer with a parallel increase in M3R expression. The role of zinc finger protein 277 in colon cancer and its relationship to M3R expression and activation are worthy of further investigation.


Subject(s)
Carcinogenesis/genetics , Colonic Neoplasms/genetics , DNA-Binding Proteins/genetics , Receptor, Muscarinic M3/metabolism , Transcription Factors/genetics , Zinc Fingers/genetics , Animals , Colonic Neoplasms/pathology , Gene Expression Regulation, Neoplastic , Humans , Mice , Mice, Knockout , RNA, Messenger/genetics , Receptor, Muscarinic M3/genetics
4.
Carcinogenesis ; 32(9): 1396-402, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21705482

ABSTRACT

M3 subtype muscarinic receptors (CHRM3) are over-expressed in colon cancer. In this study, we used Apc(min/+) mice to identify the role of Chrm3 expression in a genetic model of intestinal neoplasia, explored the role of Chrm3 in intestinal mucosal development and determined the translational potential of inhibiting muscarinic receptor activation. We generated Chrm3-deficient Apc(min/+) mice and compared intestinal morphology and tumor number in 12-week-old Apc(min/+)Chrm3(-/-) and Apc(min/+)Chrm3(+/+) control mice. Compared with Apc(min/+)Chrm3(+/+) mice, Apc(min/+)Chrm3(-/-) mice showed a 70 and 81% reduction in tumor number and volume, respectively (P < 0.01). In adenomas, ß-catenin nuclear staining was reduced in Apc(min/+)Chrm3(-/-) compared with Apc(min/+)Chrm3(+/+) mice (P < 0.02). Whereas Apc gene mutation increased the number of crypt and Paneth cells and decreased villus goblet cells, these changes were absent in Apc(min/+)Chrm3(-/-) mice. To determine whether pharmacological inhibition of muscarinic receptor activation attenuates intestinal neoplasia, we treated 6-week-old Apc(min/+) mice with scopolamine butylbromide, a non-subtype-selective muscarinic receptor antagonist. After 8 weeks of continuous treatment, scopolamine butylbromide-treated mice showed a 22% reduction in tumor number (P = 0.027) and a 36% reduction in tumor volume (P = 0.004) as compared with control mice. Compared with Chrm3 gene ablation, the muscarinic antagonist was less efficacious, most probably due to shorter duration of treatment and incomplete blockade of muscarinic receptors. Overall, these findings indicate that interplay of Chrm3 and ß-catenin signaling is important for intestinal mucosal differentiation and neoplasia and provide a proof-of-concept that pharmacological inhibition of muscarinic receptor activation can attenuate intestinal neoplasia in vivo.


Subject(s)
Butylscopolammonium Bromide/pharmacology , Genes, APC , Intestinal Neoplasms/prevention & control , Intestine, Small/pathology , Muscarinic Antagonists/pharmacology , Receptor, Muscarinic M3/physiology , Animals , Female , Intestinal Neoplasms/pathology , Male , Mice , Mice, Inbred C57BL , Receptor, Muscarinic M3/genetics , beta Catenin/analysis
5.
J Pharmacol Exp Ther ; 333(3): 639-49, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20197374

ABSTRACT

Previous work suggests that vagus nerve disruption reduces hepatocyte and oval cell expansion after liver injury. The role of postneuronal receptor activation in response to liver injury has not been ascertained. We investigated the actions of scopolamine, a nonselective muscarinic receptor antagonist, and specific genetic ablation of a key cholinergic receptor, muscarinic subtype-3 (Chrm3), on azoxymethane (AOM)-induced liver injury in mice. Animal weights and survival were measured as was liver injury using both gross and microscopic examination. To assess hepatocyte proliferation and apoptosis, ductular hyperplasia, and oval cell expansion, we used morphometric analysis of 5-bromo-2'-deoxyuridine-, activated caspase-3-, hematoxylin and eosin-, cytokeratin-19-, and epithelial cell adhesion molecule-stained liver sections. Sirius red staining was used as a measure of collagen deposition and its association with oval cell reaction. In AOM-treated mice, both muscarinic receptor blockade with scopolamine and Chrm3 ablation attenuated hepatocyte proliferation and augmented gross liver nodularity, apoptosis, and fibrosis. Compared with control, scopolamine-treated and Chrm3(-/-) AOM-treated mice had augmented oval cell reaction with increased ductular hyperplasia and oval cell expansion. Oval cell reaction correlated robustly with liver fibrosis. No liver injury was observed in scopolamine-treated and Chrm3(-/-) mice that were not treated with AOM. Only AOM-treated Chrm3(-/-) mice developed ascites and had reduced survival compared with AOM-treated wild-type controls. In AOM-induced liver injury, inhibiting postneuronal cholinergic muscarinic receptor activation with either scopolamine treatment or Chrm3 gene ablation results in prominent oval cell reaction. We conclude that Chrm3 plays a critical role in the liver injury response by modulating hepatocyte proliferation and apoptosis.


Subject(s)
Azoxymethane , Chemical and Drug Induced Liver Injury/genetics , Chemical and Drug Induced Liver Injury/pathology , Muscarinic Antagonists/pharmacology , Receptor, Muscarinic M3/genetics , Scopolamine/pharmacology , Animals , Apoptosis/drug effects , Cell Proliferation/drug effects , Hepatocytes/drug effects , Hepatocytes/physiology , Hyperplasia/pathology , Immunohistochemistry , Liver/pathology , Liver Cirrhosis/pathology , Liver Regeneration/drug effects , Mice , Mice, Knockout
6.
Am J Physiol Cell Physiol ; 296(2): C221-32, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19036940

ABSTRACT

Emerging evidence indicates that muscarinic receptors and ligands play key roles in regulating cellular proliferation and cancer progression. Both neuronal and nonneuronal acetylcholine production results in neurocrine, paracrine, and autocrine promotion of cell proliferation, apoptosis, migration, and other features critical for cancer cell survival and spread. The present review comprises a focused critical analysis of evidence supporting the role of muscarinic receptors and ligands in cancer. Criteria are proposed to validate the biological importance of muscarinic receptor expression, activation, and postreceptor signaling. Likewise, criteria are proposed to validate the role of nonneuronal acetylcholine production in cancer. Dissecting cellular mechanisms necessary for muscarinic receptor activation as well as those needed for acetylcholine production and release will identify multiple novel targets for cancer therapy.


Subject(s)
Acetylcholine/metabolism , Neoplasms/metabolism , Receptors, Muscarinic/metabolism , Signal Transduction , Animals , Antineoplastic Agents/pharmacology , Apoptosis , Cell Movement , Cell Proliferation , Disease Progression , Humans , Ligands , Muscarinic Antagonists/pharmacology , Neoplasms/drug therapy , Neoplasms/pathology , Neurons/metabolism , Protein Conformation , Receptors, Muscarinic/chemistry , Receptors, Muscarinic/drug effects , Signal Transduction/drug effects
7.
Cancer Res ; 68(10): 3573-8, 2008 May 15.
Article in English | MEDLINE | ID: mdl-18483237

ABSTRACT

Colon epithelial cells express and most colon cancers overexpress M(3) muscarinic receptors (M(3)R). In human colon cancer cells, post-M(3)R signaling stimulates proliferation. To explore the importance of M(3)R expression in vivo, we used the azoxymethane-induced colon neoplasia model. Mice treated with weekly i.p. injection of saline [10 wild-type (WT) mice] or azoxymethane (22 WT and 16 M(3)R(-/-) mice) for 6 weeks were euthanized at 20 weeks. At week 20, azoxymethane-treated WT mice weighed approximately 16% more than M(3)R(-/-) mice (33.4 grams +/- 1.0 grams versus 27.9 grams +/- 0.5 grams; mean +/- SE, P < 0.001). In azoxymethane-treated M(3)R(-/-) mice, cell proliferation (BrdUrd staining) was reduced 43% compared with azoxymethane-treated WT mice (P < 0.05). Whereas control mice (both WT and M(3)R(-/-)) had no colon tumors, azoxymethane-treated WT mice had 5.3 +/- 0.5 tumors per animal. Strikingly, azoxymethane-treated M(3)R(-/-) mice had only 3.2 +/- 0.3 tumors per mouse (P < 0.05), a 40% reduction. Tumor volume in azoxymethane-treated M(3)R(-/-) mice was reduced 60% compared with azoxymethane-treated WT mice (8.1 mm(3) +/- 1.5 mm(3) versus 20.3 mm(3) +/- 4.1 mm(3); P < 0.05). Compared with WT, fewer M(3)R(-/-) mice had adenomas (6% versus 36%; P = 0.05), and M(3)R(-/-) mice had fewer adenocarcinomas per mouse (0.6 +/- 0.1 versus 1.7 +/- 0.4; P < 0.05). Eleven of 22 WT but no M(3)R(-/-) mice had multiple adenocarcinomas (P < 0.001). Compared with WT, azoxymethane-treated M(3)R-deficient mice have attenuated epithelial cell proliferation, tumor number, and size. M(3)R and post-M(3)R signaling are novel therapeutic targets for colon cancer.


Subject(s)
Colonic Neoplasms/genetics , Epithelial Cells/cytology , Gene Expression Regulation, Neoplastic , Receptor, Muscarinic M3/genetics , Animals , Azoxymethane/pharmacology , Cell Proliferation , Cell Transformation, Neoplastic , Humans , In Situ Hybridization , Mice , Mice, Transgenic , Models, Biological , Models, Genetic , Signal Transduction
SELECTION OF CITATIONS
SEARCH DETAIL
...